Citation
Oropharyngeal Swallowing in Parkinson's Disease

Material Information

Title:
Oropharyngeal Swallowing in Parkinson's Disease a Retrospective Comparison of Longitudinal Swallowing Function
Creator:
Valenti, Michelle E
Place of Publication:
[Gainesville, Fla.]
Florida
Publisher:
University of Florida
Publication Date:
Language:
english
Physical Description:
1 online resource (58 p.)

Thesis/Dissertation Information

Degree:
Master's ( M.A.)
Degree Grantor:
University of Florida
Degree Disciplines:
Communication Sciences and Disorders
Speech, Language and Hearing Sciences
Committee Chair:
HEGLAND,KAREN W
Committee Co-Chair:
TROCHE,MICHELLE SHEVO
Graduation Date:
4/30/2016

Subjects

Subjects / Keywords:
Barium ( jstor )
Deglutition disorders ( jstor )
Diseases ( jstor )
Esophageal sphincter ( jstor )
Liquids ( jstor )
Physiology ( jstor )
Puddings ( jstor )
Swallowing ( jstor )
Symptomatology ( jstor )
Tongue ( jstor )
Speech, Language and Hearing Sciences -- Dissertations, Academic -- UF
disease -- dysphagia -- longitudinal -- oropharyngeal -- parkinson -- parkinson-disease -- pd -- swallowing
Genre:
bibliography ( marcgt )
theses ( marcgt )
government publication (state, provincial, terriorial, dependent) ( marcgt )
born-digital ( sobekcm )
Electronic Thesis or Dissertation
Communication Sciences and Disorders thesis, M.A.

Notes

Abstract:
Aspiration pneumonia is the leading cause of death in Parkinson's disease (PD). Although it is known that swallowing changes occur in PD, there are currently no longitudinal studies that characterize swallowing dysfunction, or dysphagia, over time. The primary aim of this retrospective longitudinal study was to determine if disease duration impacts the degree of change in swallowing function and oropharyngeal physiology in people with PD over a ten to fourteen month time period. It was hypothesized that longer disease duration is associated with a more rapid decline in swallowing function, specifically increased oropharyngeal residue, increased pharyngeal transit time, and increased occurrences of laryngeal penetration and aspiration. Swallowing evaluations were retrospectively analyzed for fifty participants with PD at two time-points between 10-14 months apart. Modified Barium Swallowing Impairment Profile (MBSImP), swallow timing measures, and penetration aspiration (P-A) scores were measured. A repeated measures analysis of variance was used to compare swallowing data between the two time points. The results demonstrated various significant differences including increased pharyngeal transit time, delayed aeryepiglottic closure, worsening of P-A scores, bolus transport/lingual motion, pharyngeal stripping wave, PES opening, tongue base retraction, and pharyngeal residue. These areas of oropharyngeal swallow declined longitudinally across a wide variety of disease durations and disease severities. These findings indicate that the longitudinal physiologic changes to swallowing function lead to airway compromise and increased occurrences of penetration and aspiration. Because these changes are often asymptomatic, this study emphasizes the importance of annual videofluoroscopic evaluation (VFE) for people with PD. ( en )
General Note:
In the series University of Florida Digital Collections.
General Note:
Includes vita.
Bibliography:
Includes bibliographical references.
Source of Description:
Description based on online resource; title from PDF title page.
Source of Description:
This bibliographic record is available under the Creative Commons CC0 public domain dedication. The University of Florida Libraries, as creator of this bibliographic record, has waived all rights to it worldwide under copyright law, including all related and neighboring rights, to the extent allowed by law.
Thesis:
Thesis (M.A.)--University of Florida, 2016.
Local:
Adviser: HEGLAND,KAREN W.
Local:
Co-adviser: TROCHE,MICHELLE SHEVO.
Electronic Access:
RESTRICTED TO UF STUDENTS, STAFF, FACULTY, AND ON-CAMPUS USE UNTIL 2017-05-31
Statement of Responsibility:
by Michelle E Valenti.

Record Information

Source Institution:
UFRGP
Rights Management:
Copyright Michelle E Valenti. Permission granted to the University of Florida to digitize, archive and distribute this item for non-profit research and educational purposes. Any reuse of this item in excess of fair use or other copyright exemptions requires permission of the copyright holder.
Embargo Date:
5/31/2017
Classification:
LD1780 2016 ( lcc )

Downloads

This item has the following downloads:


Full Text

PAGE 1

ISEASE: A RETROSPECTIVE COMPARISON OF LONGITUDINAL SWALLOWING FUNCTION By MICHELLE ELIZABETH VALENTI A THESIS PRESENTED TO THE GRADUATE SCHOOL OF THE UNIVERSITY OF FLORIDA IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR TH E DEGREE OF MASTER OF ARTS UNIVERSITY OF FLORIDA 2016

PAGE 2

2016 Michelle Elizabeth Valenti

PAGE 3

To the people of the the pleasure of working with through Neuro Challenge Foundation and UF Center for Movement Disorders and Neurorestoration: you have been a constant source of inspiration T his docum ent is dedicated to each of you.

PAGE 4

4 ACKNOWLEDGMENTS There are many people who have helped me throughout this process, and I am grateful to all of you. First, I must thank my family for being an endless source of encouragement, love, and happiness. I would also like to express my appreciation to Steven Bailey for his constant support and dedication, and for always finding a way to make me laugh, even during the most stressful times. I cou ld not have done this without you. I would like to extend gratitude to my committee chair Dr. Karen Hegland and my committee member, Dr. Michelle Troche, for their mentorship throughout this experience. Their passion, enthusiasm, and knowledge inspired m e to explore my interest in research. It was their dedication of time and expertise that guided me through the development of this project. The opportunity to work with them over the past two years has greatly enriched my knowledge and overall graduate ex perience. Lastly, I would like to thank my classmates, lab mates, and friends, especially Seth Dornisch, whose support, enthusiasm, and positive energy was truly motivating througho ut this project. Thanks to all!

PAGE 5

5 TABLE OF CONTENTS page ACKNOWLEDGMENTS ................................ ................................ ................................ .. 4 LIST OF TABLES ................................ ................................ ................................ ............ 7 LIST OF FIGURE S ................................ ................................ ................................ .......... 8 ABSTRACT ................................ ................................ ................................ ..................... 9 CHAPTER 1 INTRODUCTION ................................ ................................ ................................ .... 11 Background ................................ ................................ ................................ ............. 11 Healthy Swallow ................................ ................................ ............................... 11 Neural Substrates of Swallowing ................................ ................................ ...... 12 Cranial Nerves ................................ ................................ ................................ .. 15 Swallowing Function in PD ................................ ................................ ............... 15 Or al Preparatory Phase ................................ ................................ .................... 16 Oral Phase ................................ ................................ ................................ ....... 16 Pharyngeal Phase ................................ ................................ ............................ 17 Esophageal Phase ................................ ................................ ........................... 19 Disease Dura tion, Disease Severity, and Swallowing Function ........................ 19 Rationale and Hypotheses ................................ ................................ ...................... 22 2 METHODS ................................ ................................ ................................ .............. 25 Participants ................................ ................................ ................................ ............. 25 ase Severity and Disease Duration ................................ .............. 25 Videoradiography and Scoring ................................ ................................ ................ 26 Swallow Evaluation Procedures ................................ ................................ .............. 27 Data Analysis ................................ ................................ ................................ .......... 27 Measurements Related to Modified Barium Swallow Impairment Profile ......... 27 Measurements Related to Swallow Timing ................................ ....................... 28 Measurements Relat ed to Penetration Aspiration ................................ ............ 29 Statistics ................................ ................................ ................................ ................. 29 3 RESULTS ................................ ................................ ................................ ............... 35 Primary Aim ................................ ................................ ................................ ............ 35 Statistical Analysis ................................ ................................ ................................ .. 35 4 DISCUSSION ................................ ................................ ................................ ......... 39

PAGE 6

6 Primary Aim ................................ ................................ ................................ ............ 39 Implications of the Thin Bolus Hold ................................ ................................ .. 39 Measures of MBSImP ................................ ................................ ...................... 40 Measures of Penetration/Aspiration ................................ ................................ 42 Measures of Timing ................................ ................................ .......................... 43 MBSImP, PAS, and Timing Measures ................................ .............................. 44 Disease Duration and Dysphagia Severity ................................ ....................... 46 Limitations and Strengths ................................ ................................ ....................... 47 Implications for Future Research ................................ ................................ ...... 49 Implications for Swallow Evaluation and Intervention ................................ ....... 50 APPENDIX: MODIFIED BARIUM SWALLOW IMPAIRMENT PROFILE (MBSIMP) COMPONENTS, SCORES AND DEFINITIONS ................................ ..................... 51 LIST O F REFERENCES ................................ ................................ ............................... 52 BIOGRAPHICAL SKETCH ................................ ................................ ............................ 58

PAGE 7

7 LIST OF TABLES Table page 1 1 Overview of swallowing dysfunction ............................... 24 2 1 Participant demographics from year one ................................ ............................ 31 2 2 Modified Hoehn and Yahr Scale (1967) ................................ .............................. 32 2 3 Measures of Swallow Timing ................................ ................................ .............. 33 2 4 Penetration Aspiration Scale ................................ ................................ .............. 33 3 1 Descriptive statistics for Thin Hold ................................ ................................ ...... 37 3 2 Descriptive statistics for Sequential Thin ................................ ............................ 37 3 3 Significant differences found for timing measures for the thin hold bolus ........... 37 3 4 Non parametric analysis of Thin Hold, p<.05 ................................ ...................... 38 3 5 Non parametric analysis of Sequential Thin, p<.05 ................................ ............ 38

PAGE 8

8 LIST OF FIGURES Figure page 2 1 Method for selecting participants ................................ ................................ ........ 30 2 2 Example of fluoroscopic image of PA 1 (A; no material entering laryngeal vestibule) versus PA 8 (B; aspiration with no patient response). ........................ 34

PAGE 9

9 Abstract of Thesis Presented to the Graduate School of the University of Florida in Partial Fulfillment of the Requir ements for the Degree Master of Arts ISEASE: A RETROSPECTIVE COMPARISON OF LONGITUDINAL SWALLOWING FUNCTION By Michelle Elizabeth Valenti May 2016 Chair: Karen Hegland Major: Communication Sciences and Disorders Although it is known that swallowing changes occur in PD, there are currently no longitudinal studies that characterize swallowing dysfunction, or dysphagia, over time. The pri mary aim of this retrospective longitudinal study was to determine if disease duration impacts th e degree of change in swallowing function and oropharyngeal physiology in people with PD over a ten to fourteen month time period. It was hypothesized that lon ger disease duration is associated with a more rapid decline in swallowing function, specifically increased oropharyngeal residue, increased pharyngeal transit time, and increased occurrences of laryngeal penetration and aspiration. Swallowing evaluations were retrospectively analyzed for fifty participants with PD at two time points between 10 14 months apart. Modified Barium Swallowing Impairment Profile (MBSImP), swallow timing measures, and penetration aspiration (P A) scores were measured. A repeated m easures analysis of variance was used to compare swallowing data between the two time points. T he results demonstrated significant decline in specific physiologic measures in relation to disease duration, including increased pharyngeal transit time and de layed

PAGE 10

10 aryepiglottic fold closure. There were also areas of significant decline that occurred between visit one and visit two across disease durations. These include worsening of P A scores, bolus transport/lingual motion, pharyngeal stripping wave, pharyng o esophageal sphincter (PES) opening, tongue base retraction, and pharyngeal residue. T hese findings indicate that there are longitudinal physiologic changes to swallowing function that occur over a ten to fourteen month time period as well as with increas ed disease duration Because these changes are often asymptomatic, this study emphasizes the importance of annual videofluoroscopic evaluation (VFE) for people with PD.

PAGE 11

11 CHAPTER 1 INTRODUCTION Background disease (PD) is a progressive disease of the nervous system that is characterized by the degeneration of the dopaminergic neurons in the basal ganglia. (Blonsky et al 1975; Bushmann et al 1989, Critchley et al 1976; Logemann, 1973; Leopold, 1996; Ra ming et al 1988). Peo ple with PD commonly experience resting tremor, rigidity of the muscles, bradykinesia, difficulty with initiating movement and reduced range of motion (Mulcahy, 2012). Dysphagia, or swallowing dysfunction, is a symptom of Parkinson Early swallowing changes in PD include patient reports of coughing, sialorrhea, and choking (Menezes, 2009). As dysphagia becomes more severe, movement abnormalities in swallow can result in penetration or aspiration of ingested food or liquid unintentional weight loss, pneumonia, and increase overall morbidity and mortality (Menezes, 2009, Johnston et al., 1995, Wang et al 2002). The ways in which dysphagia in PD changes as disease durati on and severity increase remains unclear, yet this relationship is critical to understand in order to maintain safety and efficiency of swallow ing throughout the disease process Healthy Swallow Swallowing is a complex behavior that requires finely coordi nated neuromuscular relaxations and contractions with areas of high and low pressure in order to safely and efficiently transport the bolus from the mouth to the stomach. The process of swallowing can be divided into four stages: 1) the oral preparatory st age 2) oral transit phase, 3) pharyng eal phase, 4) esophageal phase (Groher & Crary, 2010). In the oral preparatory

PAGE 12

12 stage the material is manipulated and mixed with saliva into a cohesive unit, or a bolus. The second stage is the oral phase, in which the tongue forms, contains, and propels the bolus from the mouth to the pharynx. Sensory receptors in the tongue and oropharynx are stimula ted, which triggers the pharyngeal phase of swallow. The oral preparatory phase and the oral transit phase are both considered to be under voluntary control (Groher & Crary, 2010; Troche, 2014) The third stage is the pharyng eal phase In this stage, food and liquid are transferred from the mouth to the esophagus. As the base of the tongue propels the bolus, pharyngeal movement, including pharyngeal constriction, epiglottic inversion, cessation of breathing, laryngeal closure, a nd hyolaryngeal elevation all ow for safe passage of the bolus through the upper airway and into the proximal esophagus. The fourth and final stage is the esophageal stage, where the bolus enters the esophagus and is transported distally by orderly muscular contractions known as perist alsis (Groher & Crary, 2010) Neural Substrates of Swallowing Swallowing is a sensorimotor process that requires the sophisticated integration of volitional and autonomic systems within a complex neural substrate. Specifically, s wallowing involves the cr anial nerves, brainstem, cerebellum, limbic system, subortex, and neocortex. Dysphagia in neurodegenerative diseases including PD is likely a reflection of the patho logical alterations in the neurophysiologic control of swallowing (Sessle, 1989). The oral preparatory and oral transit phases are largely under volitional control (Troche, 2014). The volitional initiation of swallowing is neurologically represented in the cerebral cortex, which has direct access to the nuclei of the tractus solitaries (NTS). T he NTS is a structure with bilateral representation that is involved in autonomic control and

PAGE 13

13 the regulation of visceral function including the upper alimentary and respiratory tracts associated with swallowing (Sessle, 1989). As well, t he insular cortex p lays an integral role in the sensory motor integration between cortical and subcortical sites and in the regulation of movement and temporal sequencing in swallowing (Augustine, 1996; Mosier, et al., 1999; Troche, 2014). Some aspects of swallowing are thought to be purely reflexive, brainstem mediated response s This is most likely not the case because food items are rarely swallowed the same way each time, regardless of the similarity in bolus type and size. Instead, swallowing represents a patterned t ype of neurologic response that can be influenced by control centers above the level of the brainstem. (Leopold & Daniels, 2010). The modulation of the oral and pharyngeal swallowing and voluntary and involuntary behaviors requires major contributions from s upramedullary structures Throughout all of the stages of swallow, the subcortical structures are likely involved in the coordination and adaption of peripheral structures various bolus volumes and characteristics (Groher & Crary, 2010; Leopold & Daniels 2010 ; Sharman et al., 2013 ) The sensory and motor control systems of swallowing are found at three distinct levels of the nervous system. The first level of neurologic control is the brainstem swal low center in the upper medulla (Groher & Crary, 2010 ; Kennedy & Kent, 1988 ). This center is bilaterally distributed within the reticular formation, contains afferent and efferent components, and is collectively regarded as the swallowing central pattern generator (CPG). The swallow CPG is divided into dorsal and ventral components. The dorsal neurons are found in the NTS and the adjacent reticular formation. The nucleus ambiguous (NA) and the reticular formation contain the ventral neurons. This system

PAGE 14

14 sequentially activates the excitatory motor neurons that i nnervate mu s cles involved in swallowing e xecution in healthy individuals (Kennedy & Kent, 1988; Mistry & Hamdy, 2008). Damage to the brainstem, particularly the medulla, can cause very severe dysphagi a (Groher & Crary, 2010) The second level of neurologic control of swallowing involves the subcortex. The subcortical structures are responsible for monitoring and modifying the swallowing movements of learned motor patterns. At this level, sensory stimuli and feedback play critic al roles. Reduced dopamine input to subcortical brain structures, specifically to the sensorimotor network, is a hallmark of PD (Sharman et al. 2013). Damage or reduced dopaminergic input to the subcortex can affect both sensory and motor pathways, result ing in problems in both the oral and pharyngeal stages of swallow (Groher & Crary, 2010 ). Therefore, people with PD often have a sensorimotor dysphagia characterized by prolonged oral transit time, delay ed initiation of the pharyngeal phase of the swallow, and impaired coordination of other neuromuscular components of the pharyngeal swallow (Logemann, 1998 ; Sharman et al., 2013; Suzuki et al 2003 ). The third level of neurologic swallow control is the cortical modulation of swallow. This level responds to perceived changes in the need to modify feeding behavior. Examples of volitional behaviors during swallowing under cortical control include the need to eat faster, the need to expectorate an unwanted bolus, or the need to talk and masticate (chew) simulta neously. Various regions of the cerebral cortex that are active during swallow include supplementary motor cortices, orbitofrontal operculum, and the medial and superior portions of the anterior cingulate gyrus. (Michou & Hamdy, 2009; Martin & Sessle, 1993 ). In terestingly, some of these areas are only activated with water

PAGE 15

15 and thickened liquids. Studies have shown that there is activation of multiple cortical and subcorti c al sites, including the basal ganglia (Groher & Crary, 2010 ). Cranial Nerves The musc les involved in swallowing are innervated by several cranial nerves. The mandibular branch of CN V innervates the muscles for mastication and CN VII innervates the lower facial muscles, allowing the buccinator muscles to tighten the lips and flatten the ch eeks as food moves across the teeth. CN XII also plays a crucial role in that it provides the innervation necessary f or the movement of the tongue (Groher & Crary, 2010). The oral transit phase is requires the use of CN XII and CN V, which innervate the t ongue and floor of mouth muscles. The cranial nerves that are responsible for innervating the velum in order to form the lingua velar seal that separates the oral and nasal cavities are CN V, CN X, and CN XI The pharyngeal phase is the most complex in ter ms of sensorimotor integration and coordination. It is supported by cranial nerves V, VII, XI, X, and XII and activates subcortical networks, particularly the posterior insula ( Groher & Crary, 2010; Jean, 2001; Troche, 2014). Swallowing F unction in PD Pe ople with PD may experience changes in all phases of swallow. It remains unclear which phase of swallow is most impaired and if changes to swallow correlate with disease duration and disease severity. However, there is consensus regarding the fact that swa llowing changes can occur in the earliest stages of PD. Often times, these changes go unnoticed due the concomitant sensory changes associated with sease ( Van Lieshout et al., 2011; Rodrigues et al., 2011; Tjaden, 2008).

PAGE 16

16 Oral Preparatory Pha se There is a range of dysphagic symptoms that can be found in the oral preparatory phase of swallow in people with PD. Oral phase impairments are often the first symptom of dysphagia in people with PD (Tjaden, 2008). Mastication is often prolonged, delayed, and inefficient due to movement abnormalities such as lingual tremor, lingual pumping, prolonged lingual elevation, and slowed mandibular excursion (Van Lieshout et al., 2011, Ali et al., 1996; Nagaya et al., 1998). Other oral preparatory phase findings include drooling, labial bolus leakage, and oral residue. Drooling in PD is not an indicator of excess saliva; in fact, people with PD often suffer from xerostomia, which is a contributor to piecemeal deglutition. Instead, drooling can be attributed to the reduced frequency of spontaneous swallow in people with PD (Nagaya et al., 2008; Stroudley et al., 1991; Born et al., 1996; Coates et al., 1997). Studies have shown that impairments in this phase of swallow, specifically drooling, correlate with silent aspiration and laryngeal penetration (Nobrega et. al, 2008; Rodrigues et al., 2011). Oral Phase Particular attention has been given to the smaller and more variable lingual movements in the horizontal plane in people with PD Van Lieshout et al first described this symptom, which is found early in the disease, and suggested it may lead to difficult y swallowing liquids safely and efficiently ( Van Li eshout et al., 2011 ). As well, lingual pumping is associated with other oral phase deficits including intraoral leaks and residue in the pharynx after swallow, which may contribute to laryngeal penetration and aspiration (Argolo et al 2015 ). There are con tradictions regarding oral transit times in had

PAGE 17

17 participants with an average H&Y severity rating of 2.3, abnormal oral movements such as lingual pumping are associated with sho rter oral transit times, particularly in foods with thick consistencies (Argolo et al 2015 ). On the contrary, several studies have reported a positive correlation between the number of lingual pumps and oral transit time (Troche et al, 2007; Van Lies hout, P et al., 2011 ). Longer oral transit times may facilitate improved pharyngeal coordination and therefore safer swallowing overall (Van Lieshout, et al., 2011 ). Pharyngeal Phase Changes in the pharyngeal phase of swallow have also been identified. The mot or symptoms of PD, such as bradykinesia, affect pharyngeal swallowing. These changes include reduced frequency of spontaneous swallowing and slow but coordinated sequence of movements (Ertekin et al., 2002). People with PD also often experience a significant delay in the triggering of the pharyngeal swallow reflex due to the slowness of the sequential muscle movements, particularly the suprahyoid subm ental muscles (Ertekin et al, 2002). Pharyngeal peristalsis is often impaired in this population, w hich leads to weakness of the pharyngeal constrictors. (Nagaya et al, 1998). Pharyngeal transit time is often increased due to delayed or abnormal contraction of the pharyngeal wall, decreased epiglottic range of motion, stasis in the pyriform si nuses, inc oordination of the PES and delayed laryngeal elevation and excursion (Ali et al., 1996; Blonsky et al., 1975; Coates & Bakheit, 1997; Cook, 2006; Ertekin et al., 2002; Leopold & Kagel, 1997) Residue in the vallecular and pyriform sinuses are commonly pre sent after swallow (Nagaya et al, 1998). Leopold et al. attribute this residue to defective epiglottic inversion and/ or pharyngeal dysmotility (Leopold et al., 1997 ).

PAGE 18

18 Rodrigue s et al. found that many people with PD have decre ased sensitivity of the epiglot tis and posterior wall of the hypopharynx, as well as decreased sensitivity in the aryepiglottic folds and interarytenoid area. The decreased sensation in these areas increases risk for aspiration or laryngeal penetration Interestingly, the re was no diff erence between groups with and without silent aspiration in regards to the disease duration, H&Y scale, drooling score, or age. Furthermore, it was found that after a 1 year follow up of patients who had silent laryngeal penetration/ silent aspiration (SLP /SA) t here was a 9.7 fold higher risk of respiratory infection as compared with the controls without SLP/SA (Rodrigues et al., 2011). The lack of correlation between silent aspiration and disease severity, disease duration, and the other factors listed abo ve may be attributed to a small sample size of 28 participants and warrants further investigation. The larynx plays a crucial role in swallowing, particularly for airway protection (Eckberg et al., 1982 ). Leopold et al. found that many people with PD expe rience slow or delayed laryngeal excursion, slow and incomplete closure, and some patients ex hibited no closure. There is a strong positive correlation between slowed laryngeal closure and slowed laryngeal elevation. Leopold et al. also found slow ed vert ical laryngeal excursion, true vocal fold closure, and delayed, incomplete, or absent opening of the true vocal cords (Leopold et al., 1997 ). People with a n H&Y score of IV and V had significantly more occurrences of slow laryngeal excursion, slow larynge al opening, and absent closure, whereas the occurrences for slow laryngeal closing relative to bolus arrival in the hypopharynx had very similar occurrence rates across H&Y scores Although age and disease duration were recorded as part of the demographic data, this

PAGE 19

19 information was not statistically analyzed. Therefore, it is not clear whether age or disease duration contributed to the findings (Leopold et al., 1997) In addition t o the motor changes of the larynx, people with PD demonstrate poor sensorimotor integration of swallow (H ammer, 2013; Tzelepis, 1988). Research suggests that somatosensory function and airw ay sensory function may decline as a function of disease severity a nd disease duration in PD The integration of airway sensory input for motoric co ntrol of swallowing is though t to be related to pathology of the basal ganglia and associated neural networks (Hammer, 2013). Esophageal Phase The abnormalities found in the esophageal phase of swallowing in people with PD include hypertensive lower esophageal sphincter, ineffective esophageal motility, aperistalsis, repetitive upper esophageal spasms, and, most frequently, diffuse esophageal spasm (Castell et al., 2001). The se abnormalities can lead to prolonged transit times and gastro esophageal reflux disease (Castell et al, 2001; Leopold & Kagel, 1997; Nagaya et al, 1998). Smooth muscle is controlled by the autonomic nervous system and contributes to the peristalsis of bo th the esophagus Impairments in the smooth muscle can lead to esophageal dysmotility (Athlin et al., Castell et al, 2001; 1989; Lieberman et al., 1980). Disease Duration, Disease Severity, and Swallowing Function Although swallowing changes have been rep orted in all of phases of swallow in people with PD, few studies have examined the relationship between dysphagia in PD and disease duration and severity. Studies that have examined this relationship yield conflicting results. The reasons for these conflic ting results include relatively small

PAGE 20

20 sample sizes, limited diversity in terms of the range of disease severity and disease duration, and varying methods used to evaluate swallow function. There are studies that show a positive correlation between dysphagia severity and both disease severity and disease duration (Coates et al., 1997; Ptoulska, 200 3 ) In one study, participants were separated into two groups; one group had clinical dysphagia and the other group did not have clinical dysphagi a (Ptoulska 200 3) They found that the PD group with clinical dysphagia presented with a significantly higher degree of disability based on the H&Y score compared to the PD group without clinical dysphagia. Disease duration was also longer in the PD group with dysphagia, however the difference was not statistically significant. The technique used to assess swallowing reflex and laryngeal movemen ts was EMG and esophageal scinti graphy. It is important to note that none of the 18 PD participants in this study had an H&Y score above 3 (Ptoulska 200 3 ). Other studies have examine d the relationship between disease severity and dysphagia severity without an emphasis on disease duration. Clarke et al., for example, found that swallowing speed and bolus volume were si gnificantly lower in correlation with more severe H&Y scores. However, videofluoroscopic evaluation was only used in this study (Clarke et al, 1998) Nagaya et al. also found a positive relationship between disease severity and dysphagia severity. They included people with PD with H&Y scores 3 5 and found a significant correlation between disease severity and changes in oropharyngeal swallow function. Participants with a n H &Y score of 5 exhibited significantly longer stage transition duration and total swallow duration compared to PD

PAGE 21

21 patients with lower H&Y scores and an age matched control group (Nagaya et al., 1998). On the other hand, many studies have found that dysp hagia severity is not related to either clinical staging or disease duration. Specifically, some studies found that clinical staging and disease duration did not consistently predict radiographic abnormality (Fuh et al., 1996; Bushmann, 1989) Fuh et al. s study had limited ran ges in terms of disease duration, with eight years as the greatest disease duration, and clinical staging with 1.9 as the mean H& Y score (Fuh, 1996 ). Castell et al. did not iden tify a correlation betwee n these disease staging and sw allowing measures This study focused specifically on the esophageal phase of swallowing, as opposed to the oropharyngeal phase (Castell et al., 2001). Ali et al. also analyze d oropharyngeal dysphagia in PD in relation to disease duration and disease sever ity. The authors found that the presence of dysphagia was not related to duration or overall disease severity. All patients in this study (N = 19) had mild to moderate disease severity, less than IV on the H&Y scale, and the average disease duration was ap proximately 7 years (Ali et al., 1996). Some studies state that disease severity does not have a significant correlation with severity of dysphagia (Ertekin et al., 2002; Nilsson et al., 1996) However, in one of the se studies there was o nly one participa nt with a n H&Y score above 3. Furthermore, the focus of this study was on the physiology of the oropharyngeal phase and was evaluated using electrophysiologic al paramete rs rather than videofluoroscopy (Ertekin et al, 2002). Nilsson et al. also report the lack of correlation between disease severity and dysphagia severity.

PAGE 22

22 their swallowing dysfunction did not correlate with the severity of swallowing dysfunction. Upon quantitatively assessing t he swallows of the 75 patients using the repetitive oral suction swallow ( ROSS ) test, the authors found that the H&Y score and the results of the ROSS test did not correlate. It is important to emphasize that the elements of the swallow that were examined in this study were all quantitative and included suction pressure, bolus volume, swallowing capacity and timing measure of different events in the swallowing cycle (Nilsson et al., 1996). Due to the lac k of consensus in the current literature regarding the relationship between dysphagia severity, disease duration, and clinical staging, th e goal of the current study is to enhance our understanding of the relationship between these variables Furthermore, this study will investigate the magnitude of changes in swallowing related outcomes with disease progression over a 10 14 month period, or one year follow up, over a range of disease durations and severities Rationale and Hypotheses Although there are m any inform ative studies that explore the swallowing abnormalities found in people with PD, there are few studies that longitudinally examine the wa ys in which dysphagia progresses as the duration and severity of PD increases. The goal of this retrospectiv e study is to examine the degree of change in swallow function over a 10 14 month (one year follow up) time period in a large cohort of people with PD. As well, we aim to determine the effect of disease duration and disease seve rity according to the H&Y an d UPDRS scores on the rate of change in swallowing function. In order to achieve these goals we have identified two specific aims: 1. To determine whether specific measures of oropharyngeal swallowing physiology exhibit significant changes over a 10 14 mont h period in people with PD.

PAGE 23

23 It was hypothesized that there would be a significant increase in oral and pharyngeal residue, increased pharyngeal transit time, and increased occurrences of laryngeal penetration or aspiration. 2. To determine whether disease duration and/or clinical staging impact the rate of change in swallowing function in people with PD. It was hypothesized that longer disease duration and clinical staging will be associated with a more rapid decline in swallowing function, as evidenced by larger changes in measures of oropharyngeal swallowing physiology, within a 10 14 month timeframe in people with PD.

PAGE 24

24 Table 1 1. Overview of s wallowing d ysfunction s d isease Swallow phase Primary symptoms Oral Preparatory prolonged, delayed, and inefficient mastication impaired bolus formation lingual tremor lingual pumping prolonged lin gual elevation slowed mandibular excursion sialorrhea labial bolus leakage oral residue Oral piecemeal deglutition inability to efficiently propel bolus posteriorly preswallow spill delay in swallowing reflex Pharyngeal reduced base of tongue retraction decreased range of motion of epiglottis residue in vallecular and pyriform sinuses inadequate extent or duration of UES opening impaired laryngeal vestibular closure compromised airway protection Esophageal aperistalsis delayed opening of LES gastroesophageal reflux disease (GERD)

PAGE 25

25 CHAPTER 2 METHODS Participants The study was a retrospective review and analysis of clinical fluoroscopic swallow studies completed at the University of Florida Center for Movement Disorders and Neurorestoration (UF CMDNR) between the years 2011 and 2015 Electronic medical records of all patients referred for swallowing evaluations at th e UF CMDNR were reviewed in order to identify participants wh o met the following criteria: 1 ) Adults trained movement disorders neurologist, and according to s trict UK Br ain Bank criteria; 2 ) No coexisting neurologic or medical diagnoses including stroke, head and neck cancer, or COPD ; 3 ) More than 1 swallowing evaluation within a ten f ourteen month time frame; and 4 ) Surgical intervention for PD, deep brain stimulation (D BS), was permitted, as long as there was no change in lead placement in the time b etween swallow studies in this retrospective analysis. The study was approved by the University of Florida The fifty selected PD participants were seen at the Center for Movement Disorders and Neurorestora tion from 4/20/2011 to 7/28/2015 for swallowing evaluations. Disease specific factors were identified through the use of the electronic medical records system, E PIC including disease duration, disease severity, diagnosis, levodopa equivalent dose, sex, age, and the presence of Deep Brain Stimulators (DBS). Each patient underwent a comprehensive clinical assessment to determine EPIC.

PAGE 26

26 Neurologists at the UF Movement Disorders Center completed this assessment. Severity was measured usi ng the Modif i ed Hoehn & Yahr Scale (Table 2 2 ) and the Rating Scale (UPDRS). The UPDRS assesses cognition, ability to perform activities, mentation, activities of daily living, and neurological examination in order to quantify the primary and secondary motor symptoms of a person with PD. For the purposes of this project, the portions included in the statistical analysis were mentation and mood (I), portions of self evaluation of activities of daily life (ADLs) including speech, swallowing, and saliva (II), and the motor exam portion (III). The Hoehn and Yahr scale (H & Y) is widely used specifically to define broad categories of motor function in PD. Progress in H & Y stages has been found to correlate with motor decline and neuroima ging studies of dopaminergic loss. The information regarding the and staging history. Videoradiography and Scoring Swallowing function was an alyzed using videofluoroscopy. The im ages were recorded to Kay Elemetrics S wallowing Signals Lab (Kay Elemetrics, Lincoln Park, NJ) and in disc format in the patient files Images w ere electronically recorded at 29 .7 frames per second. These images were accessible at UF Center for Movement Di sorders and Neurorestoration. The images were extracted and placed onto a secure network with t he identified Each participant was assigned a participant number and visit number. The person analyzing the data was blinded to t he patient identity and visit number (1 or 2) during data analysis. The following measures were collected: Penetra tion Aspiration (PA) Score traditional swallow timing

PAGE 27

27 measur es, and MBSImP score s (Kendall et a., 2000, Martin Harris et al 2008; Rosenbek, 1996). Swallow Evaluation Procedures Swallowing functio n was evaluated according to a standard clinical protocol using videofluoroscopy. Briefly, patients were seated in the lateral viewing plane. The following is the clinical protocol used to administ er the rehabilitatio n barium swallowing evaluation. Protocol steps two through four were selected for the current study. 1. Two teaspoons of thin liquid barium (Varibar ): patient is instructed to hold mate rial in the mouth until clinician prompts patient t o swallow. 2. One cup to hold material in the mouth until the clinician prompts the patient to swallow 3. swallow back to back, without taking cup away from the lips 4. One teaspoon of pudding thick b instructed to hold material in the mouth u ntil the clinician prompts patient to swallow. 5. Two teddy graham crackers mixed with one t easpoon of pudding thick barium: Patient told to swallow when ready. 6. One cup sip of thin liquid barium (liquid wash): Patient told to swall ow when ready Data Analysis Measurements Related to Modified Barium Swallow Impairment Profile The retrospective ana lysis of swallowing function was completed using the Modified Barium Swa llow Impairment Profile, or MBSI mP MBSImP is a standardized evaluation of modified bar ium swallow evaluations that assesses 17 critical components of s wallowing and provides a profil e regarding the physiologic impairment affecting adult swallowing function. Each of the components is ordinally ranked (Martin Harris, 2008).

PAGE 28

28 The MBSImP scoring sheet can be found in Appendix A. The examiner who completed t he scoring was trained in MBSImP The program consists of a learning zone, a training zone, and a reliability zone. In order to complete the training and becom e a reliable scorer, one must achieve a s core of 80% in the Reliability Testing. The Reliability Testing is comprised of ten vid eofluoroscopic evaluations. The rater is to provide an overall score for each of the seventeen components for each of the ten videofluoroscopic evaluations. For the current study, the rater assessed the following consistencies: 1) thin hold 2) thin sequent ial 3) pudding hold. MBSImp components 1 (lip closure), 3 (bolus preparation/mastication), 13 (pharyngeal contraction A/P view only), and 17 (Esophageal Clearance) were not scored in this study due to inability to visualize the structures necessary for the se measures. Measurements Related to Swallow Timing The temporal relationship between swallow gestures and the timing of bolus transport was analyzed in order to gain insight into the physiology of the swallow. Measurements of swallow timing were analyze d using the recordings of swallow trials viewed in Image J an image processing and analysis computer program (Schneider et al., 2012 ) Image J allows the examiner to analyze the recording frame by frame. The primary examiner of the swallow timing measures w as trained in evaluating modified barium swallow studies. She was b linded to the identities and visit number of the participants. The examiner measured various swallow events, which are described in Table 2 3 Using these events, specific latencies between events were calculated Specifically, p haryngeal transit duration (PTT) was derived from the arrival of the bolu s head in the vallecular sinuses until the bol us tail passes through the pharyngo

PAGE 29

29 esophageal sphincter (PES) Aryepiglottic fold closure (AEcl ose B1 ) was measured in relation to when the bolus head leaves the mandibular ramus Measurements Related to Penetration Aspiration The evaluation of the penetration/aspiration scores was completed using the valid and reliable Penetration Aspiration Scale (P A Scale; Rosenbek et al., 1996; Table 2.4 ). The P A scale (PAS) is used to measure if material enters the laryngeal vestibule, and, if so, it determines if residue remained or if it was expelled. Flu oro scopic images that repr esent PA of 1 and 8 can be found in Figure 2 2. An expert rater took these measures by analyzing the swallow frame by frame while blinded identity and visit number Statistics A repeated measures analy sis of variance (RM ANOVA) was u sed for wi thin s ubject factors of t ime (visit 1 versus visit 2) This was completed for each bolus consistency (thin hold, pudding, and sequential). In order to detect whether disease duration affected these measures or their change between visit 1 and 2, it (disease duration) was included as a covariate in th e repeated measures models. The presence of DBS was included as a between subjects factor. For related samples, the Wilcoxon signed rank test was used to test for differences in MBSImP and PA scores between the first and second visits.

PAGE 30

30 Figure 2 1. Method for selecting p articipants Final 50 participants In participants with DBS, eliminated those who had changes to DBS lead(s) between swallow studies Eliminated participants with comorbidities (hx of head and neck cancer, stroke, COPD) Consecutive swallow studies (10 14 months apart) Confirmed PD Diagnosis ~900 potential participants

PAGE 31

31 Table 2 1 Participant demographics from year o ne Participant Number Sex Age H&Y UPDRS DBS 1 Female 72 2 19 NA 2 Male 78 3 32 NA 3 Male 81 2 20 L STN 4 Male 69 3 34 NA 5 Female 77 4 38 Bi STN 6 Male 82 3 64 NA 7 Male 70 3 38 Bi STN 8 Male 63 3 34 Bi GPi 9 Female 69 2.5 36 R GPi 10 Male 60 4 47 R STN 11 Male 68 2 21 NA 12 Male 77 2.5 28 NA 13 Male 69 3 23 Bi STN 14 Male 76 2 28 Bi STN 15 Male 59 4 43 Bi STN 16 Male 72 3 22 Bi STN 17 Male 81 3 31 NA 18 Male 82 4 35 NA 19 Male 75 3 35 Bi STN 20 Male 73 2 31 NA 21 Female 79 3 30 NA 22 Male 65 2 19 NA 23 Male 62 2 14 R STN 24 Male 81 2 28 NA 25 Male 70 1.5 10 Bi STN 26 Male 50 3 31 NA 27 Male 87 4 48 NA 28 Male 75 2 27 NA 29 Male 63 2 33 NA 30 Male 65 4 38 NA 31 Female 72 2 19 NA 32 Male 71 3 37 NA 33 Female 76 4 50 Bi STN 34 Female 69 3 33 Bi GPi 35 Male 59 2.5 23 R GPi 36 Male 61 2.5 38 NA 37 Male 65 2.5 40 L Vim,R STN 38 Male 74 2 26 NA 39 Male 69 3 35 NA 40 Male 46 2 29 Bi STN 41 Male 73 2 23 NA 42 Male 61 4 44 L STN

PAGE 32

32 Table 2 1. Continued Participant Number Sex Age H&Y UPDRS DBS 43 Male 76 2 32 NA 44 Male 78 3 27 NA 45 Male 55 2.5 29 L STN 46 Male 66 2 11 NA 47 Male 46 2.5 19 Bi STN,R GPi 48 Male 68 2.5 39 R STN, L GPi 49 Male 36 1 15 NA 50 Male 76 2 35 NA *There were no significant changes in H&Y scores and disease durations from year one to year two. Table 2 2. Modified Hoehn and Yahr Scale (1967) Stage Characteristics 1 Unilateral involvement, minimal or no functional disability 1.5 Unilateral with axial movement 2 Bilateral or midline involvement without impairment of balance 2.5 Mild Bilateral disease with recovery on pull test 3 Mild to moderate bilateral disease; some postural instability; physically independent 4 Severe disability; still able to walk or stand unassisted 5 Wheelchair bound or bedridden unless aided

PAGE 33

33 Table 2 3 Measures of Swallow Timing B1 The first moveme nt of the bolus from a stable posterior nasal spine BV1 The arrival of the bolus head in the valleculae BV2 The bolus head leaves the valleculae BP1 Arrival of the bolus at the PES BP2 Exit of the bolus tail from the PES PC1 The moment the pharyngo esophageal sphincter closes and the bolus has fully entered the esophagus POP Onset of pharyngo esophageal sphincter (PES) opening PESmax Time at which the pharyngo esophageal sphincter has reached its widest opening AEstart Onset of aryepiglottic fold elevation AEclose Aryepiglottic fold elevation to the point of supraglottic closure H1 First superior anterior movement of the hyoid H2 The point at which the hyoid reaches its maximum displacement H3 The moment the hyoid begins its descent to a resting position H4 The return of the hyoid to a stable position at the end of a swallow (Kendall et al., 2000) Table 2 4 Penetration Aspiration Scale Score Desctiption Classification of penetration or aspiration 1 Contrast does not enter the airway No Penetration/Aspiration 2 Contrast enters the airway, remains above the vocal folds Penetration 3 Contrast remains above the vocal folds with visible residue Penetration 4 Contrast contacts vocal folds, no residue Penetration 5 Contrast contacts vocal folds, visible residue Penetration 6 Contrast passes glottis, no sub glottic residue Aspiration 7 Contrast passes glottis, visible sub glottic residue despite patient response Aspiration 8 Contrast passes glottis, visible sub glottic residue absent of patient response Aspiration (Rosenbek et al., 1996)

PAGE 34

34 Figure 2 2 Exam ple of fluoroscopic image of PA 1 (A; no material entering laryngeal vestibule) versus PA 8 (B; aspiration with no patient response). B A

PAGE 35

35 CHAPTER 3 RESULTS Primary Aim Hypotheses 1 and 2 were tested by completing MBSImP measures, timing measures, an d penetrat ion/aspiration scores. These scores were compared longitudin ally within a time span of ten to fourteen months for each of the 50 par ticipants with PD. Descriptive data highlighting the most impaired swallowing components according to MBSImP and PA scores i s shown in T ables 3 1 and 3 2. Statistical Analysis Thin bolus hold: The results showed a significant interaction effect for time (visit 1 v. 2) and disease duration ( timi ng measures with disease duration as a covariate (F (8 ,38) = 2.33 ; p=.0 38 ). The presence of DBS did not have a statistically significant impact on the data (F (8,38) = 1.245 ; p = .301 ) Results of univariate tests are in Table 3 3 Sequential and Pudding Boluses: There were no significant differences found for timing measures of t he sequential sip (F (9,33) = .997; p = .461 ) or the pudding b olus (F (9,28) = 1.885; p = .096 ) Wilcoxon Signed Ranks Test, a non parametric measure, was completed for the MBSImP and PA scores There were s ignificant differences for several components of t he oropharyngeal swallow w ith the thin liquid bolus hold and the sequential sip. The significant findings are shown in Table s 3 4 and 3 5 There were no significant changes with the pudding bolus. The second hypothesis was that the rate of decline in swallow function would be influenced by disease duration. The non parametric analysis revealed that disease duration did not have a significant effect on MBSImP scores nor did it have a significant

PAGE 36

36 effect on PA score For th e two timing measures (PTT and AEclose B1) that showed correlations in order to determine the direction and strength of the relationship. There was a significant moderate correlation between AEclose B1 (time 2 time 1) and disease duration (r = .501; p < .000) and a significant but weaker correlation between PTT (time 2 time 1) and disease duration (r = .386; p = .007), indicating that the latency between these swallowin g events increases with longer disease duration.

PAGE 37

37 Table 3 1. Descriptive s tatistics for Thin Hold Component Year 1 Mean (SD) Year 2 Mean (SD) PA 2.08 (2.00) 2.82 (2.33) Bol us Tran sit 1.16 (1.08) 1.6 5(1.02) Oral Res idue 1.56 (0.61) 1.68 (0.55) Initiation 1.96 (1.18) 2.14 (1.08) TBR* 0 .98 (0.56) 1.2 (0.57) Ph aryngeal Res idue .* 0 .94 (0.74) 1.20 (0.69) *indicates significant longitudinal decline (p< .05) SD= Standard Deviation PA = Penetration Aspiration Score TBR= Tongue Base Retraction Table 3 2. Descriptive s tatistics for Sequential Thin Component Year 1 Mean (SD) Year 2 Mean (SD) PA 2.65 (1.92) 2.87 (1.97) Bolus Transit 1.30 (0.91) 1.60 (0.92) Oral Res idue* 1.50 (0.58) 1.75 (0.56) Initiation 2.04 (1.09) 2.14 (1.15) TBR 1.13 (0.65) 1.33 (0.63) Pharyngeal Residue* 1.00 (.69 ) 1 .35 (0.60) *= p<.05 Table 3 3 Significant differences found for timing measures for the thin hold bolus Component F (df) p Pharyngeal transit time 7.366 (1) .009 Aryepiglottic closure to bolus head passing posterior nasal spine 15.563(1) <.001

PAGE 38

38 Table 3 4. Non parametric a nalysis of Thin Hold, p<.05 Component p value PA .028 Bolus Transport/Lingual Motion .005 Epiglottic Inversion .046 Pharyngeal Stripping Wave .033 PES Opening .034 Tongue Base Retraction .016 Pharyngeal Residue .001 MBSImP Composite Score .001 Table 3 5. Non parametric a nalysis of Sequential Thin, p<.05 Component p value Oral Residue .008 Pharyngeal Stripping Wave .034 Tongue Base Retraction .020 Pharyngeal Residue .002 MBSImP Composite Score .00 1

PAGE 39

39 CHAPTER 4 DISCUSSION The purpose of this study was to assess swallow function and physiology in PD patients in between the one year follow up period MBSImP measures, timing mea sures, and PA scores were used to assess these changes. It was hypothesized that oropharyngeal swallowing physiology would exhibit s ignifican t changes within the one year follow up period in people with PD, specifically increased oral and pharyngeal residue, increased p haryngeal transit time, and increased occurrences of laryngeal penetration or aspiration. It was also hypothesized that the rate of change in swallowing function would increase with longer disease duration. Primary Aim Implications of the Thin Bolus Hol d The thin bolus hold demonstrated the greatest significant longitudinal decline of the three bolus types analyzed across all three measures. With this particular bolus type, the participant is required to follow a series of commands. He or she is instruc ted to take a sip from a cup, maintain the bolus with in the oral cavity, and then initiate a swallow when verbally prompted by the clinician. Not only does t his multi step command create a swallowing task with increased cognitive demand but it also leads to an unfamiliar and unnatural sequence of movements. All aspects of t his task are highly volitional and research indicates that people with PD demonstrate greater difficulty with volitional tasks versus involuntary tasks (Yamaguchi & Kabayashi, 1998). Ad ditionally, this task requires the initiation of movement to an external command. Initiation of movement is mediated by the basal ganglia Because PD is a degenerative disease involving the basal ganglia the initiation and programming of motoric movement is

PAGE 40

40 impaired, likely making this task more challenging to execute than a natural swallow sequence Furthermore, the act of holding a bolus in the oral cavity requires lingual coordination with the soft p alate Results of the current study indicate that this task becomes signi ficantly more impaired at the one year follow up visit A previous study that examines the effect of a verbal cue on bolus flow in healthy adults shows that in a cued swallow, the bol us is moved and held more posteriorly as compared to a non cued bolus hold becoming increasingly vulnerable to premature posterior spillage. The pudding hold, in which the clinician provides the same instructions as the thin hold, is not as impaired. The thi cker consistency of the pudding likely makes the bolus easier to orally manipulate and control. The challenges with the oral phase of the thin hold are then transfe rred to the pharyngeal phase of swallow due to premature posterior spillage of the bolus, reduced base of tongue retraction, and delayed triggering of the pharyngeal swallow. Measures of MBSImP MB SImP scores captured several areas of impaired swallowing f unction. For both the thin hold, the oral phase component that was significantly worse from year one to year two was bolus transport/lingual motion This finding is not surprising, considering that the swallowing mechanism is greatly impacted by t he dopami nergic pathways These pathways lead to some of the most commonly observed symptoms of PD including ri gidity and bradykinesia These symptoms of PD directly impact lingual motion, causing slow or repetitive lingual movement. Furthermore, l ingual movement during the oral stage is und er primarily voluntary control, which is mediated by cortical

PAGE 41

41 control and calibrated by subcortical control. As previously e stablished, the initiation and voluntary aspects of movements are areas of significant impairment in PD (Yamaguchi & Kabayashi, 1998). In t he pharyngeal phase pharyngeal stripping wave, epiglottic inversion, PES opening, tongue base retract ion, and pharyngeal residue were significantly worse in the second year with the thin bolus hold In the pharyngeal stage of swallow for the thin sequential bolus pharyngeal stripping wave, tongue base retraction, and also pharyngeal residue became worse between the first and second visit The MBSImP composite s core was more elevated in year two for both the thin and s equential boluses indicating overall decline in swallow function The pharyngeal components which already showed impairment in year one in both the thin hold and sequential sip, likely worsened as an influence of the decline in the oral phase of the swa llow. The increasingly bradykinetic lingual movement res ulted in the participants having to make multiple attempts to fully move the bolus posteriorly into the pharynx and initiate the swallow T he pharyngeal stage of swallow is highly reflexive. It is lik ely that w hen the volitional components of the swallow become impaired, the reflexive movements become uncoordinated and do not necessarily accommodate for the abnormalities stemming from the impaired oral phase. Although aforementioned swallow components got significantly worse longitudinally, these results were not correlated with disease duration and disease severity. This suggests that these are patterns of swallowing dysfunction that become progressively worse throughout the course of the disease

PAGE 42

42 The pudding bolus did not demonstrate any significant areas of longitudinal decline. This is not surprising, consideri ng that pudding is a thick consistency, which is helpful in cohesively contain ing the bolus a nd therefore improving oral control. Thus, there is ample time for pharyngeal phase movement to occur in a more safe and efficient fashion. For example with the thick bolus there is typically not pre swa llow spill, and thus the pharyngeal phase of swallow is more coordinated. The findings of the curren t study support this theory in that MBSImP components such as tongue base retraction and pharyngeal residue, for example, are rated as less severely impaired with the pudding bolus as compared to the thin bolus types Measures of Penetration/Aspiration The thin hold was the only bolus type to show significant longitudinal decline in PA scores Because previous studies have found that thicker consistencies are less likely to be penetrated or aspirated, it was not surprising that pudding did not show signi ficant longitudinal decline (Bulow, 2003; Kuhlemeier et al., 2001; Troche, 2008). The finding that there is no significant l ongitudinal decline with the thin sequential seems less intuitive. Interestingly, descriptive data shows that the PA score for the sequential bolus was severely impaired for both years, but did not show a significant change from one year to the next. The PA score for the thin hold, on the other hand, presented as less severely impaired than the sequential bolus in year one, and then b ecame significantl y worse in the second year It can be hypothesized that the task of holding the bolus in oral cavity exacerbated the already weakened or discoordinated lingual motion. In fact, the bolus transport/lingual motion showed a more significant longitudinal decline in the thin hold than in the sequential sip, though both bolus types showed significant decline

PAGE 43

43 I t has been established that the phases of swallow are not mutually exclusive but rather influence one another in a significant manner ( Troche, 2008; Yamaguchi & Kabayashi, 1998). T he increasingly impaired oral phase likely impacted the already compromised components of the pharyngeal phase of swallow. The areas of pharyngeal state decline with the thin hold, including pharyngeal stripping wave, PES opening, tongue base retraction, an d increased pharyngeal residue, paired with a delay in the triggering of the pharyngeal swallow is associated with increased risk of aspiration (Logemann, J.A., 1998; Yorkston, KM, 2004) Furthermore, the findi ng that aryepiglottic folds demonstrates delayed closure in the thin hold indicates that the laryngeal vestibule is vulnerable to penetration or aspiration. Measures of Timing Results indicated that the timing of the swallow with the t hin bolus hold demo nstrated significant longitudinal decline with disease duration as a covariate. There were no significant findings with the sequential sip and the pudding bolus. P haryngeal transit time, which is measured from the time head of the bolus arrives in the valleculae to wh en the bolus tail exits the P ES, increased from year 1 to year 2 and was exacerbated by disease duration The coexisting decline in bolus transport/lingual motion and increased pharyngeal transit time highlights the relationship between and oral and pharyngeal phases of swallow It can be hypothesized that the increasingly slow, weak, and repetitive tongue movements in combination with the highly volitional task of holding the thin bolu s in the oral cavity negatively impacts the physiologic functioning of the oral phase leading to preswallow spill to the pharynx T he alr e ady established areas of pharyng eal phase impairment, particularly reduced tongue base

PAGE 44

44 retraction and inadequate extent and or duration of PES opening, further increase the time it takes the bolus to move through the pharynx. This findi ng was not found with the thin sequential bolus because the task more closely approximates natural swallowing patterns and it eliminates the extra demands of the lingual musculature to consci ously hold the bolus in t he oral cavity. It can be hypothesized that pharyngeal transit time did not significantly increase over time with pudding due the low viscosity of the bolus. The thicker consistency provides better support for oral manipulation wit hout preswallow spill and cohesive posterior movement of the bolus when the swallow is triggered. The timing measures also captur ed that increased disease duration is associated with a delay in a ryepiglottic fold closure in relation to the bolus head pas sing the posterior nasal spine in the thin bolus hold. This finding corresponds with the previously mentioned finding, that PA scores demonstrated a significant longitudinal decline with this bolus type. The worsening PA score can be attributed to the mul tiple attempts to move the bolus posteriorly into the pharynx, which causes premature spillage into the posterior oral cavity and the pharynx. It is likely that the in incoordination of the oral phase, in combination with reduced tongue base retraction ca uses a delayed initiation of the swallow and therefor e a delay in the closure of the aryepigottic folds. This delay makes penetration or aspiration more likely to occur. MBSImP, PA and Timing Measures It may seem counter i ntuitive that the thin sequential bolus showed significant longitudinal decline in several components of MBSImP, but showed no significant longitudinal decline in timing measures. In order to further investigate this finding, a repeated measures analysis was conducted and the re sults showed that there was no

PAGE 45

45 correlation between MBSImP scores and timing measures. These two measures have not been directly compared before, so this finding was surprising Although it may seem as though measures of function, MBSImP, should be directly related to measures of physiology, timing measures, there are several inherent differences between the two meas ures that likely explain this lack of correlation Timing measures are analyzed one frame at a time, while MBSImP components are scored in real time. Timing measures are parametric and a direct measure of the physiology of the swallow, while MBSImP components are ordinally ranked and more subjective in that, when scoring these components, the rater has to select what he or she decides i s the most appropriate pre labe led category. Therefore, these scores may be more or less sensitive than the actual m easures of physiology, causing a lack of correlation between the two types of measures. In the current study, longitudinal changes in the sequential si p were more sensitive to measures of MBSImP than they were to timing measures. This is not to say that the timing of the swallow was not impaired in the sequential sip, but rather that the timing measures did not capture a significant l ongitudinal decline from visit 1 to visit 2, nor did it capture a significant effect for disease duration With the thin bolus hold, the results of the timing measures not only revealed a decline in certain elements of the physio logy of the swallow from visit 1 to visit 2 b ut these measures also rev ealed that disease duration further exacerbated the swallowing dysfunction. Specifically, there was a significant correlation between disease duration and increased pharyngeal transit time and increased delay in aryepiglottic fold closure in relation to the bolus passing the posterior nasal spine. This suggests that timing me asures, which are reflective of components of the physiology of the swallow, are only

PAGE 46

46 able to capture significant change when the dysfunction reaches a certain threshold of severity. Measures of MBSImP and PAS are less specific and are not reflective of specific areas of physiologic change, but instead, illustrate the result of impaired physiology At earlier disease durations, these changes may not be severe en ough to be captured by acute and specific physiologic change. However, measures of function, MBSImP and PAS, are able to capture markers of swallow dysfunction as a result of more widespread and perhaps milder changes that are present early in the disease. Disease Duration and Dysphagia Severity The subjective nature of disease duration may have influenced the lack of correlation between disease duration and swallow function in MBSImP and PAS In the current study, disease duration was recorded as the ti me of official diagnosis by a neurologist. The subjective nature of determining disease duration stems from several origins. Some people are very perceptive to changes that occur in the body. In some cases, these changes could be early symptoms of Parkinso cases, these symptoms are unrelated to PD but the patient falsely attributes them PD After noticing these changes, some people may seek a diagnosis immediately, and others may wait for years before pursuing a medical diagnosis. O n the other hand, some people are not as aware of the early symptoms of the disease and will, for instance, experience loss of smell long before the commonly known m otoric symptoms. These factor s make it challenging to create a uniform criterion for determ ining disease duration. Taking the subjective nature of this measure into consideration, this study demonstrates that there are areas of significant deterioration in swallowing function that occur in the short time span of one year across disease durations However, only the

PAGE 47

47 timing measures of PTT and AEclose B1 were significantly impacted by longer disease duration. This suggests that specific changes to swallow physiology, as captured by timing measures, are identified at later disease duration s due to the increased severity of the dysfunction ; wh ereas measures that identify problems in the function of the swallow that are not specif ic to physiology, MBSImP and PA can be identified across disease durations. Limitations and Strengths The curre nt study has several limitations. Some of these limitations are related to the retrospective nature of this study. The exa miner was unable to control for influence swall owing function Furthermore, the retrospective nature of the study did not allow the investigator to actively participate i n th e videofluoroscopic evaluation. Therefore, the current study could not control for medication state, which could possibly have an influence o n swallow function Even though there is a strict protocol that was followed at the time of the swallow studies, a prospective study would allow the primary investigator to be present and ensure the strict adherence to the protocol by providing the participants with the exact same instructions each time. By keeping the instructions consistent and direct, that would help control for the amount of cognitive load that is being placed on the participant for each swallow recorded. Additionally, a pro spective study would have allowed the investigator to reinforce that the swallowing directions were followed correctly. For example, with the thin seque ntial sip, some of the participants sip swallow wi thout removing the c participants took a pause in between each sip which inherently alters the task

PAGE 48

48 Furthermore, the thin sequential sip was sometimes not included or recorded in the evaluation possibly due to the severity of th e swallow dysfunction demonstr ated by the thin bolus hold. The inability to visualize or score the sequential sip in some of the participants that exhibited the most severe swallowing dysfunction could have potent ially skewed the results to show that the t hin bolus hold more severely impair ed than the sequential sip. Due to the prolonged nature of the oropharyngeal swallow of many of the participants, t he entirety of the swallow was sometimes n ot recorded and certain components of the swallow could not be e valuated Additionally, the anterior po rtion of the lips and tongue were often not visible in the VFE. Therefore, oral transit time could not be calculated and the examiner could not comme nt on anterior bolus spillage. After reflecting upon the current s study that examines orop haryngeal swallowing in P D The retrospective nature of the study allowed for a thorough methodology in terms of the selection of participants. The study controlled for other medical diagnoses, which may influence the patterns of swallowing dysfunction. For the participants with DBS, the current study controlled for cha nges to DBS status from year 1 to year 2 in terms of lead placement. The invest which was document ed Patient demographics were representative of a wide variety of diseas e durations and disease severities There was also a large va riety oropharyngeal dysphagia severity represented, including people with no evidence of airway compromise to people who consistently display silent aspiration. The current study i ncluded a thorough protocol for swallow analysis. Each swallow was

PAGE 49

49 analyzed using thre e different measurements: MBSImP timing measures, and PAS The combination of these measures captures both the function and the physiology of the swallow. Implications for Future Research In regards to the primary aims of this study, there are questions that remain unanswered. The effect of disease duration on rate of decline of swallow function remain s un clear. Disease du ration is a subjective measure that is difficult to control. Some people may be exceptionally perceptive to the earliest symp tom s of PD and seek a diagnosis immediately, while others might not receive a diagnosis until years after the symptoms of the disease first present. Perhaps a future prospective study would provide researchers with the opportunity to work in conjunction wi th a neurologist to develop a uniform questionnaire and dedicate ample time to speak with each individual participant in order to establish an accurate and consi stent method to estimate disease onset In order to gain a better understanding of the effect disease severity has on swallowing function, future studies should maintain a large n while also including an even distribution of H+Y scores. Eve n though the current study did not find a correlation between MBSImP and timing measures this is the first st udy to assess this correlation. Future studies should further investigate the correlation, or lack thereof, between these two measures. This study identified several components of the swallow that were most severely impaired across many disease durations and severities. It also identified the components of the swallow that g ot significantly worse in one year Future studies should expand this time frame in order to further identify components of the swallow that

PAGE 50

50 decline, and if the patterns of dysfunction are consistent with the findings identified in this study. Implications for Swallow Evaluation and Intervention This study demonstrates that there are several longitudinal changes in swallow function that occur in a one year time period in people with PD across disease durations. Because dysphagia in PD is often asymptomatic or unreported, this study indicates the importance of annual VFE to monitor swallow function as the disease progresses. It is the hope of the investigator that the current study and fu ture research will contribute to a better understanding of the patterns of swallowing dysfunction throughout the course of the disease and therefore promote targeted treatment goals and regular evaluations in order to enhance the quality of life and overal l health in

PAGE 51

51 APPENDIX A MODIFIED BARIUM SWALLOW IMPAIRMENT PROFILE (MBSIMP) COMPONENTS, SCORES AND DEFINITIONS

PAGE 52

52 LIST OF REFERENCES Ali,GN, Wallace KL, Schwartz R DeCarle DJ, Zagami AS, Cook IJ (1996). Mechanisms of oral G astroenterology 110 : 383 392. Argolo, N., Sampaio, M., Pinho, P., Me lo A., Nobrega, AC (2015) Swallowing Disorders in PD: Impact of lingual pumping. Int J Lang Commun Disord 10:1460 6984. Blonsky ER, Logemann JA Boshes B Fisher HB (1975) Comparison of speech and swallowing function in patients with tremor disorders and normal geriatric patients: a cineflu orographicstudy. J Gerontol 30: 299 303 Born LJ, Harned RH, Rik k ers LF, Pfeiffer RF, Quigley EM (1998) Cricopharyngeal Mov. Disord. 11 : 53 58. Bryne KG, Pfeiffer R, Quigley disease: a report of clinical experience at a single center. J Clin Gastoenerol 19: 11 6. Bulow, M., Olsson, R., & Ekberg, O. (2003) Videoradiographic analysis of how carbonated thin liquids and thi ckened liquids affect the physiology of swallowing in subjects with aspiration on thin liquids. Acta Radioloica 44: 366 372. Bushmann M Dobmeyer SM, Leeker L Perlmutter JS (1989) Swallowing abnormalities and their response to treatment i n Parkins Neurology 39(10): 13 09 14. Castell, JA, Johnston, BT, Colcher, A., Li, Q., Gideon, RM, Castell DO (2001) disease Neurogastroenterol Motil 13: 361 4. Clarke, CE, Gulla ksen, E., Macdonald, S., Lowe F. (1998) Referral criteria for speech and language therapy assessment of dysphagia caused by idiopathic isease. Acta Neurol Scand 97: 27 35. Coates C Bakeit AMO (1997) Eur Neurol 38 : 49 52. Cook, I (2006). Clinical disorders of the upper esophageal sphincter. GI Motility online 10.1038. Critchley EMR (1981). Speech disorders of parkinsonism: a review. J N eurol Neurosurg Psychiatry 44: 751 758.

PAGE 53

53 Daniels S., Schroeder M., DeGeorge P., Corey D., Rosenbek J.C. (2007). Effects of Verbal Cue on Bolus Flow During Swallowing. American Journal of Speech Language Pathology. 16: 140 147. Dozier TS, Brodsky MB, Michel Y, Walters BC, Jr., Martin Harris B. (2006). Coordin ation of swallowing and respiration in normal sequential cup swal lows. Laryngoscope. 116 : 1489 1493. Eadie MJ, Tyrer JH (1965) Radiological abnormalities of the upper part of the alimentary tract in parkinsonism. Aust Ann Med 14: 23 7. Edwards LL, Quigley EMM, Pfeiffer RF (1992) Gastrointestinal dysfunction in Parki Neurology 42: 726 32. Ekberg O Sigurjonsson SV (1982) Movement of the epiglottis during deglut ition. Gastrointest Radiol 7: 101 107. Ertekin C Tarlaci S Aydogdu I Kiylioglu N Yuceyar N Turman AB, Secil Y Esmeli F (2002) Electrophysiological evaluation of pharyngeal phase of swallowing in patients with Park Mov Disord 17: 942 9. Fuh JL, Lee RC, Wang SJ, Lin CH, Wang PN, Chiang JH, et al. (1997) Swallowing diffi ase. Clin Neurol Neurosurg 99:106 12. Groher M Crary, M. (2010). Dysphagia: Clinical Management in Adults and Children. Maryland Heights, MO: Mosby Elsevier. Print. Gross RD, Atwood CW, JR., Ross SB, Eichhorn KA, Olszewski JW, Doyle PJ (2008) Dysphagia 23: 136 145. Hammer MJ, Barlow disease: impli cations for speech respiratory and phonatory control. Exp Brain Res 201: 401 409. Hunter PC, Crameri J A ustin S Woodward MC Hughes AJ (1997) Response of Parkinsonian swallowing dysfunction to dopaminergic stimulation. J Neurol Neurosurg Psychi atry 63: 57 83. Jean, A. (2 001 ) Brain Stem Control of Swallowing : Neuronal Network and Cellular Mechanisms Physiological Reviews 81(2): 929 969. Johnston BT, Li Q, Castell JA, Castell DO (1995) Swallowing and esophageal e. Am J Gastroenterol 90: 1741 6. Leopold N.A., Daniels S.K. (2010). Supranuclear control of swallowing. Dysphagia. 25(3):250 257.

PAGE 54

54 Leopold, Kagel (1997). Laryngeal deglutition m ovement in Parkin so Neurology 48(2): 373 376. Leopold NA, Kagel MC (1996). Prepharyngeal d Dysphagia 11, 14 22. Logemann, JA (1997) Role of the modified barium swallow in management of patients with dysphagia. Otol aryngology 11 6(3) : 335 338 Logemann, JA (1998). Evaluation and Treatment of Swallowing D isorders. Austin, Texas: pro ed Kendall, K.A., McKenzie, S., Leonard, R.J., Goncalves, M.I. & Walker, A. (2000). Timing of events in normal swallowing: a videofluoroscopic study. Dysphagia. 15, 74 83. Kennedy J.G. III, Kent R.D. (1988). Physiological substrates of normal deglutition. Dysphagia. 3(1):24 37. Klahn MS, Perlman AL (1999) Temporal and durational pat terns associating respiration and swallowing. Dysphagia 14: 131 138. Kuhlemeier, K.V., Palmer, J.B., & Rosenberg, D. (2001) Effect of liquid bolus consistency and delivery method on aspiration and pharyngeal retention in dysphagia patients. Dysphagia 1 2: 19 20 Martin Harris B, Brodsky MB, Price CC, Michel Y Walters B (2003). Temporal coordination of pharyngeal and laryngeal dynamics with breathing during swallowing: Single liquid swallows. J Appl Physiol 94: 1735 1743. Martin Harris B Bro dsky MB Michel Y Ford CL, Walers B Heffner J (2005) Breathing and swallowing dynamics across the adult lifespan. Arch Otolaryngol Head Neck Surg 131: 762 770. Martin Harris B Brodsky MB, Michel Y Castell D Schleicher M, Sandidge J, Maxqell R, Blair J (2008) MBS Measurement Tool for Swallow Impairment MBSImp: Establishing a Standard. Dysphagia 23: 392 405. Martin, R.E., Barr, A., MacIntosh, B., Smith, R., Steven s, T., Taves, D., et al. (2007) Cerebral c ortical processing of swallowing in older adults. Experimental Brain Research 176: 12 22. Martin, R. E., Goodyear, B. G., Gati J. S., & Menon, R. S. (2001) Cerebral cortical representation of automatic and volitional swall owing in humans. J Neurophysiol 85(2): 938 950.

PAGE 55

55 Martin R.E., Sessle B.J. (1993). The role of the cerebral cortex in swallowing. Dysphagia. 8(3): 195 202. Melo, A., Monteiro, L (2013) Swallowing improvement after levodopa treatment in disease: Lack of Evidence. Parkinsonism and Re lated Disorders 19(3): 279 281. Michou E., Hamdy S. (2009) Cortical input in control of swallowing. Curr Opin Otolaryngol Head Neck Surg. 17(3):166 171. Miller, M. Noble E., Jones, D., Burn, D (2006) Hard to swallow: dysphag ia in Age Ageing. 35 (6): 614 618. Mistry S., Hamdy S. (2008) Neural control of feeding and swallowing Phys Med Rehabil Clin N Am. 19(4): 709 728. Monte, FS da Silva Junior, FP, Braga Neto, P., Nobre e Souza, MA, de Bruin, VA. (2005) Swa llowing abnormalities and dyskinesia in Parki nson Mov Disord. 20: 457 62. Monteiro, D., C oriolano, M., Belo, L., Lins, O (2014) The relationship between dysphagia and clinical types in P CEFAC 16 (2). Mulcahy, P. (2012) Devel opment of a Dual Combining Environmenta l and Genetic Risk Factors Nagay a M Kachi T Yamada T Igata A (1998) Videoflurographic study of Dysphagia 13: 95 100. Nilsson, H., Ek berg, O., Olsson, R., Hindfelt B. (1996) Quantitative assessment of oral and pharyngeal function in Parki Dysphagia 11: 144 50. Nishino T., Hiraga, K (1991) Coordination of swallowing and respiration in unconscious subjects. J Appl Physiol 70: 988 993. Pener A Druckerman LJ (1942) Segmental spasms of the esophagus and their relationship to parkinsonism. Am J Dig Dis 9: 282 6. Pinnington LL, Muhiddin KA, Ellis RE, Playford ED (2000) Non invasive assessment of swallowing an J Neurol 247: 773 777 Potulska A., Friedman, A., Krolicki L. Spychala A. (2003) Swallowing disorders in Parkinsonism and Related Disorders 9: 349 353. Proulx, de Courval, Wiseman, Panisset ( 2005) Salivary production in Parki disease Mov Disord 20: 204 7.

PAGE 56

56 Ramig LA, T itze OR, Scherer RC, Ringel SP (1988) Acoustic analysis of voices of patients with neurologic disease: rationale andpreliminary data Ann Otol Rhinol Laryngol. 97(2): 16 4 172. Robbin s JA, Logemann JA, Kirshner HS (1986) Swallowing and s peech pr oduction in Ann Neurol 19: 283 287. Rodrigues B, Nobrega AC, Sampaio M Argolog N ., Melo, A (2011) Silent saliva Mov. Disord. 26(1): 138 41. Schneider, C., R asband, W., Eliceiri, K. (2012) NIH Image to ImageJ: 25 years of image analysis. Nature Methods. 9: 671 675. Schwarz, F. (1995) Parkinsonian medication one hour before meals improves symptomatic swallow ing case study. Dysphagia 10: 165 6. Sessle, B., Henry, J. (1989) Neural Mechanisms of Swallowing: Neurophysiological and Neurochemical Studies on Brain Stem Neurons in the Solit ary Tract Region. Dysphagia 4: 61 75. Shaheen, H. (2006) Role of cerebral cortex i n the control of swallowing. GI Motility Online 10: 1038. Sharman, M., Valabregue, R., Perlbarg, V., Marrakchi Kacem, L., Vidailhet, M., Brice, A., Lehericy, S (2013) subcortical s ensorimotor connectivit y. Movement Disorders 4 : 447 54. Stroudley J Walsh M (1991) Radiological assessment of dy disease. Br J Radiol 64: 890 893. Sutton, J (2013) Parkinsonism and Related Disorder 16: 282 284. Suzuki M., Asada Y., Ito J., Hayashi K., Inoue H., Kitano H. (2003). Activation of cerebellum and basal ganglia on volitional swallowing detected by functional magnetic resonance imaging. Dysphagia. 18(2):71 77. Tjaden K. (20 08). Speech and Swallowing in Parkin Geri Rehab 24(2): 115 126. Troche, M. S., Okun, M. S., Rosenbek, J. C., Altmann, L. J., & Sapienza, C. M. (2014) Attentional resource allocation and swallowing safety in Parkinson's disease: a dual task st udy. Parkinsonism & related disorders 20 ( 4): 439 443. Troche, M.S., Sapienza, C.M., & Rosenbek, J.C. (2008) Effects of bolus consistency on Dysphagia 23: 26 32.

PAGE 57

57 Van Lieshout, P., Steele, C., Lang, A. (2011) Tongue control for swallowing in onsistency. Mov Disorders 26 (9) : 1725 1729. Wang XD, You GF, Chen HB, Cai XJ (2002) Clinical course and cause of death in elderly patients wi th idiopathic Parkin Chin Med J. 115: 1409 11. Yamaguchi, S., & Kabayashi, S. (1998) Contributions of the dopaminergic system to voluntary and automatic orienting of visuospatial attention. Journal of Neuroscience 18: 281 286. Yorkston, KM Miller RM, Strand, EA (2004) Management of Speech and Swallowing in Degenerative Disease s. Austin, Texas: Pro ed. Zald, D., Pardo, J. (1999) The functional neuroanatomy of voluntary swallowing. 1999. Ann Neurol 46: 281 286.

PAGE 58

58 BIOGRAPHICAL SKETCH Michelle Valenti graduated with her Bachelor of Arts degree in English and received a minor in linguistics from the University of Florida in 2013. She graduated cum laude. She will complete the requirements for the Master of Arts degree in speech pa thology at the University of Florida as well. After graduation, Michelle hopes to neurodegenerative disease s