Michael S Okun

University of Florida, Lake Alfred, FL, USA

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Publications (205)816.42 Total impact

  • Article: Respiratory-swallowing coordination and swallowing safety in patients with Parkinson's disease.
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    ABSTRACT: The purpose of this study was to determine if individuals with Parkinson's disease (PD) demonstrate abnormal respiratory events when swallowing thin liquids. In addition, this study sought to define associations between respiratory events, swallowing apnea duration, and penetration-aspiration (P-A) scale scores. Thirty-nine individuals with PD were administered ten trials of a 5-ml thin liquid bolus. P-A scale score quantified the presence of penetration and aspiration during the swallowing of a 3-oz sequential bolus. Participants were divided into two groups based on swallowing safety judged during the 3-oz sequential swallowing: Group 1 = P-A ≤ 2; Group 2 = P-A ≥ 3. Swallows were examined using videofluoroscopy coupled with a nasal cannula to record respiratory signals during the event(s). Findings indicated that expiration was the predominant respiratory event before and after swallowing apnea. The data revealed no differences in our cohort versus the percentages of post-swallowing events reported in the literature for healthy adults. In addition, individuals with decreased swallowing safety, as measured by the P-A scale, were more likely to inspire after swallows and to have shorter swallowing apnea duration. Individuals who inspired before swallow also had longer swallowing apnea duration. The occurrence of inspiratory events after a swallow and the occurrence of shorter swallowing apnea durations may serve as important indicators during clinical swallowing assessments in patients at risk for penetration or aspiration with PD.
    Dysphagia 09/2011; 26(3):218-24. · 1.39 Impact Factor
  • Article: DBS candidates that fall short on a levodopa challenge test: alternative and important indications.
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    ABSTRACT: Candidacy for deep brain stimulation (DBS) in Parkinson disease (PD) is typically assessed by the preoperative motor response to levodopa along with an interdisciplinary evaluation. However, recent cases treated at our institution have achieved good outcomes with DBS despite a sub-30% improvement in motor scores. The aim of this study was to examine the outcomes of DBS in a subset of patients who failed to reach the 30% motor improvement threshold. A review of all DBS patients treated at the University of Florida Movement Disorders Center between 2002 and 2009 was performed utilizing a DBS database. All patients with sub-30% improvement in Unified Parkinson Disease Rating Scale Part III after dopaminergic medication administration were included. Nine patients were identified; DBS was performed for severe dyskinesia (n=5), "on/off motor" fluctuations (n=1) and medication-refractory tremor (n=3). The target symptoms were improved in all patients. Postoperatively, scores on the Unified Parkinson Disease Rating Scale Part II and III and subscores on Parkinson disease questionnaire-39 improved (P<0.05). Although motor response to levodopa remains the primary selection criteria for DBS candidacy in Parkinson disease, patients who do not meet the 30% threshold and have disabling symptoms may still benefit from DBS. Select patients with severe dyskinesia, "on/off" motor fluctuations, and/or medication-refractory tremor may experience significant benefits from DBS and should be considered on a case by case basis through an interdisciplinary team evaluation.
    The Neurologist 09/2011; 17(5):263-8. · 1.26 Impact Factor
  • Article: Unilateral GPi-DBS as a treatment for levodopa-induced respiratory dyskinesia in Parkinson disease.
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    ABSTRACT: Respiratory dyskinesia is a rare but disabling complication of levodopa therapy for Parkinson disease; however, its treatment has been limited to medication optimization. A 72-year-old woman with a 6-year history of Parkinson disease presented with severe and debilitating levodopa-induced respiratory dyskinesia, which manifested with a short and shallow breathing pattern and panting. These symptoms were observed coincident with limb and truncal dyskinesias. Both respiratory and limb/trunk dyskinesias were addressed by the implantation of a unilateral globus pallidus interna deep brain stimulator (GPi-DBS). Although the mechanism of involvement of the respiratory system in dyskinesia is unknown, GPi-DBS seems to be a potentially viable treatment option for these patients.
    The Neurologist 09/2011; 17(5):282-5. · 1.26 Impact Factor
  • Article: Unilateral deep brain stimulation surgery in Parkinson's disease improves ipsilateral symptoms regardless of laterality.
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    ABSTRACT: Researchers have consistently observed in right-handed individuals across normal and disease states that the 'dominant' left hemisphere has greater ipsilateral control of the left side than the right hemisphere has over the right. We sought to determine whether this ipsilateral influence of the dominant hemisphere reported in Parkinson's disease extends to treatments such as deep brain stimulation (DBS) and whether it affects outcome. We hypothesised that among Parkinson right-handers, unilateral left DBS would provide greater ipsilateral motor improvement compared with the ipsilateral motor improvement experienced on the right side. A total of 73 Parkinson patients who underwent unilateral DBS of the subthalamic nucleus (STN) or globus palidus internus (GPi) participated. Left and right 'composite scores', were computed by separately adding all items on the left and right side from the motor section of the Unified Parkinson Disease Rating Scale. The change in the pre- and 4-month post-implantation score was the primary outcome measure. The mean motor scores improved by 4.96 ± 11.79 points (p < 0.001) post-surgery on the ipsilateral side of the DBS implantation. Regression analyses revealed that the side (left vs. right) and target (STN vs. GPi) did not significantly contribute in the effect of ipsilateral motor improvement (p = 0.3557). While DBS on the 'dominant' left side failed to exert a greater ipsilateral influence compared with DBS on the non-dominant right side, significant ipsilateral motor improvements were observed after unilateral stimulation regardless of site of implantation and laterality.
    Parkinsonism & Related Disorders 08/2011; 17(10):745-8. · 3.80 Impact Factor
  • Article: Rescue leads: a salvage technique for selected patients with a suboptimal response to standard DBS therapy.
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    ABSTRACT: We present four cases where supplementary "rescue" deep brain stimulation (DBS) leads were added for patients who failed to obtain anticipated clinical benefits. Nine patients out of 295 patients who underwent DBS between 2002 and 2009, were identified as rescue lead recipients. Of these nine cases, four cases were evaluated. Two had medication refractory tremor which was incompletely suppressed by Vim (nucleus ventralis intermedius) thalamic DBS, and supplemental rescue leads were implanted in either the VO (ventral oralis) thalamic nucleus or the STN (subthalamic nucleus). The remaining two cases were patients with severe dystonia who were initially treated with bilateral GPi (globus pallidus internus)-DBS, and following suboptimal clinical benefits, a second GPi rescue lead was added in a case, and bilateral STN rescue leads were added in the other case. Outcomes of scores collected included Fahn-Tolosa-Marin Tremor Rating Scale (TRS) for tremor cases and the Unified Dystonia Rating Scale (UDRS) for dystonia cases and the symptom specific patient global impression scales (PGIS; 7 point scale). In the tremor cases, the TRS scale improved by 34.1 ± 7.4% and the PGIS following rescue lead was "minimally improved" to "very much improved" (range 1-2). In dystonia cases, the UDRS improved by 50.0 ± 23.6% and the PGIS was "minimally improved" to "very much improved" (range 1-2) after rescue lead surgery. This small retrospective case series demonstrated that, in appropriately selected patients with suboptimal results of standard DBS therapy, the addition of rescue lead(s) may provide meaningful clinical benefit.
    Parkinsonism & Related Disorders 07/2011; 17(6):451-5. · 3.80 Impact Factor
  • Article: Alternate but do not swim: a test for executive motor dysfunction in Parkinson disease.
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    ABSTRACT: The objective of this study is to learn if participants with Parkinson disease (PD), when compared to normal controls, are impaired in making simultaneous but independent right and left hand movements. Participants were tested with Luria's Alternating Hand Postures (AHP) test and modified AHP tests. Twelve PD participants without dementia and twelve matched controls were assessed for their ability to perform the parallel AHP test (both hands remaining in the same coronal plane) and with modifications of this test into swimming (alternative arm extension with finger extension and arm flexion with finger flexion) and reverse swimming (alternative arm extension-finger flexion and arm flexion-finger extension) movements. The participants with PD were significantly impaired when performing the parallel and the reverse swimming movements AHP tests, but not impaired on the swimming movements AHP test. Swimming movements may be phylogenetically and ontogenetically more primitive and not as heavily dependent on frontal-basal ganglia networks; thus performance of swimming movements during the parallel AHP test may decrease this test's sensitivity. (JINS, 2011, 17, 702-708).
    Journal of the International Neuropsychological Society 07/2011; 17(4):702-8. · 2.76 Impact Factor
  • Article: Nonmotor manifestations of dystonia: a systematic review.
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    ABSTRACT: Nonmotor symptoms are increasingly recognized as important determinants of quality of life and disability in a wide range of movement disorders. There is a limited body of research suggesting that many of these symptoms are also commonly associated with primary and other genetic forms of dystonia. However, the significance, etiology, pathophysiology, and treatment of these symptoms remain poorly described. The following is a review of the literature that focuses primarily on the association of these types of dystonia with psychiatric disorders, cognition, sleep, pain, and autonomic symptoms. We will also discuss potential mechanisms and approaches to treatment for nonmotor features of dystonia.
    Movement Disorders 06/2011; 26(7):1206-17. · 4.51 Impact Factor
  • Article: Did General Douglas MacArthur have Parkinson disease? A video and archival analysis.
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    ABSTRACT: Historians have suggested that MacArthur had Parkinson disease (PD), and that this may have influenced his military judgment. There is little evidence to support or to refute this suggestion. We aimed in this article to review multiple cinematic images, as well as the personal writings of Douglas MacArthur to determine the likelihood that he had PD. A complete review of the Western literature on Douglas MacArthur, including YouTube, Google Scholar/Google Images/Google Video, PubMed, and HighWirePress was undertaken. Over 200 minutes of film footage was analyzed, including such factors as MacArthur's facial profiles, facial expression, gait, posture, and movement. Handwriting samples from over 6 decades were compared for evidence of micrographia. Videos and handwriting samples were independently reviewed by 3 fellowship-trained movement disorders neurologists. Examination of video footage showed evidence of progression of head tremors, postural action tremors, and voice tremors. There were no clear indications of a masked face, rigidity, bradykinesia, or a resting tremor on film footage recorded from 1906 to 1964. There was no evidence of micrographia in handwriting samples. Oral testimony and letters written by an attending gastroenterologist present at MacArthur's death in 1964 revealed no evidence of parkinsonian features. We conclude that MacArthur had mild essential tremor that was more evident in his postmilitary career. There was no evidence to suggest that he had a clinical diagnosis of progressive PD.
    Neurology 05/2011; 76(19):1668-72. · 8.31 Impact Factor
  • Article: Mixed results for GPi-DBS in the treatment of cranio-facial and cranio-cervical dystonia symptoms.
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    ABSTRACT: The aim of the study is to determine clinical outcomes in patients undergoing Globus Pallidus Internus Deep Brain Stimulation (GPi-DBS) for cranio-facial and cranio-cervical dystonia (Meige) symptoms. A total of 6 patients seen between 2002 and 2010 with cranio-facial and cranio-cervical dystonia symptoms were identified from the University of Florida Institutional Review Board approved database. Patients were videotaped using a standardized protocol, and tapes were randomized and blindly reviewed by a movement disorders neurologist. The Unified Dystonia Rating Scale improved 31.6 ± 23.2% (range: 3.4-63.2%) at 6 months and 63.7 ± 35.3% (range: 6.3-100%) at 12 months. The Burke-Fahn-Marsden Dystonia Rating Scale improved 45.3 ± 29.5% (range: 4.7-75.0%) at 6 months and 61.8 ± 30.9% (range: 16.6-100%) at 12 months. One patient significantly had a very large improvement with little evidence of residual dystonia. Blepharospasm improved in all patients, whereas speech and swallowing did not improve in this cohort. Two patients improved with unilateral GPi-DBS, although one required a contralateral DBS later in the disease course. Two patients were managed with low frequency stimulation (<100 Hz). Two patients had less than 20% benefit. GPi-DBS for cranio-facial and cranio-cervical symptoms is an effective strategy to manage a subset of patients who remain unresponsive to optimized medical management. Unilateral stimulation may be an option for some patients, but it remains unclear whether response to single-sided stimulation will be sustainable. The mixed results of this GPi-DBS case series highlight the need for a careful re-examination of selection criteria, alternative brain targets, and possibly rescue leads for patients who are non-responders to the GPi target.
    Journal of Neurology 05/2011; 258(11):2069-74. · 3.47 Impact Factor
  • Article: Lessons learned from a large single center cohort of patients referred for DBS management.
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    ABSTRACT: Deep brain stimulation surgery (DBS) for movement disorders has become commonplace and patients are beginning to present to specialized centers for second opinions. We aimed to uncover reasons for referral by analyzing a large single center cohort of DBS patients referred for management. Data were collected prospectively on a cohort of one hundred and eight patients who presented to the UF Movement Disorders Center for management following implantation at outside DBS centers. Data collected included referral reasons, pre-operative evaluation, DBS programming thresholds, DBS placement, need for optimization of therapy, and ultimate patient outcomes. Ninety percent of patients reported at least one area of symptomatic dissatisfaction with the results of their DBS. Common issues included pre-operative misdiagnosis (28%), presence or exacerbation of symptoms not addressable by current DBS technology (48%), lead misplacement (43%), and need for medication (27%) or DBS programming (37%) optimization. Compared with leads placed using microelectrode recording (MER), leads placed without MER were strongly associated with misplacement (p = 0.03). Overall, 42% of subjects had no improvement, 37% slight improvement and 21% large improvement after medical and/or surgical management. This study reveals common reasons why DBS patients may seek follow-up care at another institution. Although 90% of patients reported one or more problematic areas, many of these could not be addressed by current DBS technology. Similar to prior studies, we found that lead misplacement was prominent, as was the need for optimization of medicines and/or stimulation.
    Parkinsonism & Related Disorders 05/2011; 17(4):236-9. · 3.80 Impact Factor
  • Article: Delayed clinical improvement after deep brain stimulation-related subdural hematoma. Report of 4 cases.
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    ABSTRACT: The purpose of this paper is to present 4 cases that illustrate the management and outcome of subdural hematoma (SDH) following deep brain stimulation (DBS) lead implantation. The authors identified 4 cases of SDH following DBS lead implantation from a pool of 500 consecutive lead implantations (incidence 0.08%) performed at the University of Florida. Cases were characterized by chart review, serial Unified Parkinson's Disease Rating Scale evaluations, and changes on serial postoperative imaging studies. Two of the 4 patients with DBS-related SDH were clinically symptomatic. In the other 2 cases the SDH was incidentally discovered on routine postoperative lead localization imaging studies. None of the patients required craniotomy for evacuation of the SDH in the acute phase. Three of the 4 cases were managed with bur hole drainage in the chronic phase, and one was successfully managed nonoperatively. In all 4 cases, thresholds for stimulationinduced side effects were lower during initial postoperative programming than during intraoperative macrostimulation. Expected clinical improvement from DBS was achieved without lead revision in all 4 cases, but only after a significant delay. Subdural hematoma is a rare and potentially avoidable complication of DBS that does not typically mandate acute hematoma evacuation or hardware revision and does not preclude an excellent outcome from DBS therapy. The clinical picture and apparent lead position tend to improve with time, and it may be wise to delay repositioning of an ineffective DBS lead following a hemorrhage until the DBS lead and surrounding brain tissue have settled into their final position and the insulted brain has had sufficient time to recover.
    Journal of Neurosurgery 04/2011; 115(2):289-94. · 2.96 Impact Factor
  • Article: The case for testing memory with both stories and word lists prior to dbs surgery for Parkinson's Disease.
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    ABSTRACT: Patients seeking deep brain stimulation (DBS) surgery for Parkinson's disease (PD) typically undergo neuropsychological assessment to determine candidacy for surgery, with poor memory performance interpreted as a contraindication. Patients with PD may exhibit worse memory for word lists than for stories due to the lack of inherent organization in a list of unrelated words. Unfortunately, word list and story tasks are typically developed from different normative datasets, and the existence of a memory performance discrepancy in PD has been challenged. We compared recall of stories and word lists in 35 non-demented PD candidates for DBS. We administered commonly used neuropsychological measures of word list and story memory (Hopkins Verbal Learning Test, Logical Memory), along with a second word list task that was co-normed with the story task. Age-corrected scores were higher for the story task than for both word list tasks. Compared to story recall, word list recall correlated more consistently with motor severity and composite measures of processing speed, working memory, and executive functioning. These results support the classic view of fronto-subcortical contributions to memory in PD and suggest that executive deficits may influence word list recall more than story recall. We recommend a multi-componential memory battery in the neuropsychological assessment of DBS candidates to characterize both mesial temporal and frontal-executive memory processes. One should not rely solely on a word list task because patients exhibiting poor memory for word lists may perform better with stories and therefore deserve an interdisciplinary discussion for DBS surgery.
    The Clinical Neuropsychologist 04/2011; 25(3):348-58. · 2.12 Impact Factor
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    Article: Hospitalization in Parkinson disease: a survey of National Parkinson Foundation Centers.
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    ABSTRACT: To explore current practices and opinions regarding hospital management of Parkinson disease (PD) patients in specialized PD Centers. Fifty-one out of 54 National Parkinson Foundation (NPF) Centers worldwide completed an online survey regarding hospitalization of PD patients. Many Centers were concerned about the quality of PD-specific care provided to their patients when hospitalized. Primary concerns were adherence to the outpatient medication schedule and poor understanding by hospital staff of medications that worsen PD. Few Centers had a policy with their primary hospital that notified them when their patients were admitted. Rather, notification of hospitalization came often from the patient or a family member. Several Centers (29%) reported not finding out about a hospitalization until a routine clinic visit after discharge. Quick access to outpatient PD care following discharge was a problem in many Centers. Elective surgery, fall/fracture, infection, and mental status changes, were identified as common reasons for hospitalization. There is a perceived need for PD specialists to be involved during hospitalization of their patients. Improvement in communication between hospitals and PD Centers is necessary so that hospital clinicians can take advantage of PD specialists' expertise. Education of hospital staff and clinicians regarding management of PD, complications of PD, and medications to avoid in PD is critical. Most importantly, outpatient access to PD specialists needs to be improved, which may prevent unnecessary hospitalizations in these patients.
    Parkinsonism & Related Disorders 03/2011; 17(6):440-5. · 3.80 Impact Factor
  • Article: Management of the hospitalized patient with Parkinson's disease: current state of the field and need for guidelines.
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    ABSTRACT: To review the literature and to identify practice gaps in the management of the hospitalized Parkinson's disease (PD) patient. Patients with PD are admitted to hospitals at higher rates, and frequently have longer hospital stays than the general population. Little is known about outpatient interventions that might reduce the need for hospitalization and also reduce hospital-related complications. A literature review was performed on PubMed about hospitalization and PD between 1970 and 2010. In addition, in press peer-reviewed papers or published abstracts known to the authors were included. Information was reviewed by a National Parkinson Foundation workgroup and a narrative review article was generated. Motor disturbances in PD are believed to be a causal factor in the higher rates of admissions and complications. However, other conditions are commonly recorded as the primary reason for hospitalization including motor complications, reduced mobility, lack of compliance, inappropriate use of neuroleptics, falls, fractures, pneumonia, and other important medical problems. There are many relevant issues related to hospitalization in PD. Medications, dosages and specific dosage schedules are critical. Staff training regarding medications and medication management may help to avoid complications, particularly those related to reduced mobility, and aspiration pneumonia. Treatment of infections and a return to early mobility is also critical to management. Educational programs, recommendations, and guidelines are needed to better train interdisciplinary teams in the management of the PD patient. These initiatives have the potential for both cost savings and improved outcomes from a preventative and a hospital management standpoint.
    Parkinsonism & Related Disorders 03/2011; 17(3):139-45. · 3.80 Impact Factor
  • Article: Do stable patients with a premorbid depression history have a worse outcome after deep brain stimulation for Parkinson disease?
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    ABSTRACT: Deep brain stimulation (DBS) has been associated with mood sequelae in a subset of patients operated on in either the subthalamic nucleus or the globus pallidus internus for the treatment of Parkinson disease. To compare mood and motor outcomes in those with and without a presurgical history of depression. Unilateral subthalamic nucleus or unilateral globus pallidus internus DBS patients followed up for a minimum of 6 months were included. All patients underwent a comprehensive outpatient psychiatric evaluation by a board-certified psychiatrist. Psychiatric diagnoses were based on Diagnostic and Statistical Manual, fourth edition, text revision, nomenclature (American Psychiatric Association, 2000). Motor and mood outcomes were compared. A total of 110 patients were included. There were no significant differences in baseline variables between the 2 groups. Those with a preoperative history of depression had significantly higher Beck Depression Inventory scores than the nondepression group after DBS (8.97 ± 7.55 vs 5.92 ± 5.71; P = .04). Patients with a depression history had less improvement (11.6%) in pre/post-DBS change when Unified Parkinson Disease Rating Scale motor scores were compared (P = .03) after adjustment for stimulation site and baseline demographic and clinical variables. Patients with a higher levodopa equivalent dose had a worse clinical motor outcome. Patients with a preoperative depression history had higher Beck Depression Inventory scores after DBS and significantly less (albeit small) improvement in pre/post-DBS change in Unified Parkinson Disease Rating Scale motor scores than patients without a history of depression.
    Neurosurgery 03/2011; 69(2):357-60; discussion 360-1. · 2.79 Impact Factor
  • Article: Clock drawing in the Montreal Cognitive Assessment: recommendations for dementia assessment.
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    ABSTRACT: Clock drawing is part of the Montreal Cognitive Assessment (MoCA) test but may have administration and scoring limitations. We assessed (1) the reliability of the MoCA clock criteria relative to a published error scoring approach, (2) whether command-only administration could distinguish dementia from cognitively intact individuals and (3) the value of adding a clock copy condition to the MoCA. Three novice raters and clocks from dementia and control participants were used to assess the 3 aims. MoCA interrater and intrarater reliability were low (i.e. intraclass correlation coefficient = 0.12-0.31) and required repeat training. Clocks drawn to command classified dementia at chance. Inclusion of a copy condition demonstrated expected dementia subgroup patterns. Reliable clock scoring with MoCA criteria requires practice. Supplementing a clock copy to the standard MoCA test (takes <1 min) will improve dementia assessment.
    Dementia and Geriatric Cognitive Disorders 03/2011; 31(3):179-87. · 2.14 Impact Factor
  • Article: Steady or not following thalamic deep brain stimulation for essential tremor.
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    ABSTRACT: Deep brain stimulation (DBS) has become an important option for medication-refractory essential tremor (ET), but may contribute to worsened gait and falling. This study evaluates impaired gait in a cohort of patients treated with DBS with a retrospective review of ET patients before and after DBS implantation. Factors examined included: age, duration of symptoms, pre-morbid gait difficulties/falls, Fahn-Tolosa-Marin tremorrating scale (TRS) scores at baseline, 6 months post-unilateral DBS implantation, and 6 or 12 months post-bilateral implantation. All implantations targeted the nucleus ventralis intermediate (Vim). Thirty-eight patients (25 males, 13 females) were included. Twenty-five patients (65.8%) underwent unilateral DBS implantation and 13 (34.2%) bilateral. The mean age at surgery was 67.1 years ± 11.4 (range 34-81). The mean disease duration was 31 years ± 18.3 (range 6-67). Fifty-eight percent of patients had worsened gait post-operatively. Seventy percent of patients with unilateral Vim DBS experienced gait worsening while 55% of bilateral DBS patients experienced gait worsening. Patients with worsened gait post-DBS had higher baseline pre-operative TRS scores than those without worsened gait (43.1 points ± 8.4 vs. 33.1 points ± 10.1, p = 0.002) (odds ratio 2.5, p = 0.02). Gait/balance may worsen following DBS for medication refractory ET. Higher baseline TRS score may factor into these issues, although a larger prospective study will be required with a control population. The larger percentage of difficulties observed in unilateral versus bilateral cases likely reflected the bias not to proceed to second-sided surgery if gait/balance problems were encountered.
    Journal of Neurology 03/2011; 258(9):1643-8. · 3.47 Impact Factor
  • Article: Generic versus branded pharmacotherapy in Parkinson's disease: does it matter? A review.
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    ABSTRACT: There is an ongoing debate about generic drug use for a multitude of conditions including epilepsy, psychosis, hypertension, post-organ transplantation, and several infectious diseases. Most of the concerns involve drugs with narrow therapeutic indices. There is a heightened attention to health care costs and macroeconomic policy as well as microeconomic business decisions that may impact the use of generic drugs. The issues surrounding generic substitution for chronic degenerative conditions such as in Parkinson's disease (PD) continue to be controversial subjects for physicians, pharmacists, patients, Medicare/governmental insurance programs, and for private insurance companies. The United States Food and Drug Administration (FDA) requires that generic drugs meet a standard for bioequivalence prior to market approval, but this may not translate to therapeutic efficacy or to overall patient tolerance. In this review we will address issues related to the use of generics versus branded drugs in PD, and the potential impact substitution of generics may have on patients and on clinicians. Having proper documentation may help in deciding the appropriate usage of these drugs in PD. Medicare, governmental run health care systems, and third party insurance companies should in a complex disease such as PD, allow physicians and patients the chance to properly document the superiority of brand versus generic approaches. Currently, in the U.S, and in many countries around the world, there is no obligation for payers to respect these types of patient specific bedside trials, and there has been no standardization of the process.
    Parkinsonism & Related Disorders 02/2011; 17(5):308-12. · 3.80 Impact Factor
  • Article: Weight changes in subthalamic nucleus vs globus pallidus internus deep brain stimulation: results from the COMPARE Parkinson disease deep brain stimulation cohort.
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    ABSTRACT: Parkinson's patients, on average, gain weight after deep brain stimulation (DBS). To determine potential differences in weight gain when comparing the subthalamic nucleus and the globus pallidus internus target. A retrospective analysis was performed on the prospective, randomized cohort of National Institutes of Health COMPARE trial DBS patients who received unilateral subthalamic nucleus or globus pallidus internus DBS. Baseline weights were recorded before DBS surgery and at 6, 12, and 18 months postoperatively. Relationships between weight change and changes in Beck Depression Inventory score, Unified Parkinson's Disease Rating Scale (UPDRS) motor score (part III) (also the dyskinesia duration and disability subscores from UPDRS IV), and Hoehn-Yahr stage were determined via Spearman's rank-order correlation coefficients. Regression analyses were performed to investigate the effects of potential factors on weight change over time. Patients in the COMPARE DBS cohort gained a significant amount of weight, a mean of 4.86 lb (standard deviation = 8.73) (P = .001), but there was no significant difference between subthalamic nucleus and globus pallidus internus targets (weight gain of 4.29 ± 6.79 and 5.38 ± 10.32 lb, respectively; P = .68). Weight gain did not correlate with Beck Depression Inventory score change, UPDRS motor score, dyskinesia duration, dyskinesia disability change, or the Hoehn-Yahr stage (P = .62, .21, and .31, respectively). No specific variable was associated with weight gain, and there were no differences in binge eating post-surgery in either target. There were significant changes in weight over time after DBS therapy. However, neither Beck Depression Inventory score change nor UPDRS score change or dyskinesia was correlated with weight gain. No significant factor was associated with the weight change.
    Neurosurgery 02/2011; 68(5):1233-7; discussion 1237-8. · 2.79 Impact Factor
  • Article: Binge eating in Parkinson's disease: prevalence, correlates and the contribution of deep brain stimulation.
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    ABSTRACT: Of 96 Parkinson's disease patients surveyed at the University of Florida Movement Disorders Center, one (1%) met diagnostic criteria for binge-eating disorder. Eight (8.3%) exhibited subthreshold binge eating. Psychometric criteria classified problem gambling in 17.8%, hoarding in 8.3%, compulsive buying in 11.5%, hypersexuality in 1.0%, and mania in 1.0% of patients. More overeaters met psychometric criteria for at least one additional impulse-control disorder (67% versus 29%). No more overeaters than non-overeaters were taking a dopamine agonist (44% versus 41%). More overeaters had a history of subthalamic deep brain stimulation (DBS; 44% versus 14%). History of DBS was the only independent predictor of overeating.
    The Journal of neuropsychiatry and clinical neurosciences 01/2011; 23(1):56-62. · 2.34 Impact Factor

Institutions

  • 2002–2013
    • University of Florida
      • • Department of Neurology
      • • Department of Neurosurgery
      • • Department of Clinical and Health Psychology
      • • Department of Medicine
      Lake Alfred, FL, USA
  • 2009–2012
    • University of Colorado Denver
      • Department of Neurology
      Denver, CO, USA
    • Universitätsklinikum Freiburg
      • Zentrum für Kinder- und Jugendmedizin
      Freiburg, Lower Saxony, Germany
  • 2004–2012
    • McKnight Brain Institute
      Gainesville, FL, USA
    • Georgia Institute of Technology
      • School of Applied Physiology
      Atlanta, GA, USA
  • 2011
    • University of California, San Francisco
      • Department of Neurology
      San Francisco, CA, USA
    • University of Michigan
      • Department of Neurology
      Ann Arbor, MI, USA
  • 2010
    • Duke University
      • Department of Surgery
      Durham, NC, USA
    • Wake Forest University
      • Department of Neurology
      Winston-Salem, NC, USA
    • University of California, Los Angeles
      • Department of Medicine
      Los Angeles, CA, USA
  • 2009–2010
    • Mount Sinai School of Medicine
      • • Department of Psychiatry
      • • Department of Neurology
      Manhattan, NY, USA
  • 2008–2009
    • Wake Forest School of Medicine
      • Department of Neurology
      Winston-Salem, NC, USA
    • Lerner Research Institute
      Cleveland, OH, USA
  • 2007
    • National Institutes of Health
      • Laboratory of Neurogenetics
      Bethesda, MD, USA
  • 2006
    • National Institute on Aging
      • Invertebrate Molecular Genetics Unit
      Baltimore, MD, USA
  • 2005
    • Al-Ahliyya Amman University
      Amman, Amman, Jordan
    • University of Toronto
      • Department of Medicine
      Toronto, Ontario, Canada
    • University of Alabama at Birmingham
      • Department of Neurology
      Birmingham, AL, USA
  • 2002–2003
    • Emory University
      • Department of Neurology
      Atlanta, GA, USA