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Mehta, Shyamal H.

https://orcid.org/0000-0003-3608-4456

Mayo Clinic

Mayo Clinic

Citations 78

A Consensus Set of Outcomes for Parkinson’s Disease from the International Consortium for Health Outcomes Measurement
Roos, Paul de , Bloem, Bastiaan R. , Kelley, Thomas A., Antonini, Angelo , Dodel, Richard , Hagell, Peter , Mehta, Shyamal H. , Odin, Per , Chaudhuri, К. Ray , Wilson, Bil, Uitti, Ryan J. , Marras, Connie , Martínez‐Martín, Pablo , Weintraub, Daniel , Wilson, Bil, Antonini, Angelo

Journal of Parkinson's Disease | June 30, 2017 | Volume: 7 | Issue: 3 | Pages: 533-543

10.3233/jpd-161055 Get It

Comparison of neuropathology in Parkinson's disease subjects with and without deep brain stimulation
Ouyang, Bichun , Shill, Holly A. , Stebbins, Glenn T. , Metman, Leo Verhagen , Driver‐Dunckley, Erika , Mehta, Shyamal H. , Caviness, John N., Beach, Thomas G. , Disorders, the Arizona Study of Aging Neurodegenerative, Driver-Dunckley, Erika, Pal, Gian D. , Serrano, Geidy E. , Goetz, Christopher G. , Sabbagh, Marwan Noel , Adler, Charles H. , Disorders, the Arizona Study of Aging Neurodegenerative

Movement Disorders | December 2, 2016 | Volume: 32 | Issue: 2 | Pages: 274-277

10.1002/mds.26882 Get It

ABSTRACT Background : The aim of this postmortem study was to compare, in Parkinson's disease subjects with and without bilateral subthalamic nucleus deep brain stimulation (STN‐DBS), the loss of pigmented neurons within the substantia nigra and pathological alpha‐synuclein density within the SN and other brain regions. Methods : PD subjects were identified from the Arizona Study of Aging and Neurodegenerative Disorders database (STN‐DBS = 11, non‐DBS = 156). Pigmented neuron loss scores within the substantia nigra as well as alpha‐synuclein density scores within the substantia nigra and 9 other brain regions were compared, the latter individually and in summary as the Lewy body brain load score. Results : DBS subjects had higher alpha‐synuclein density scores within the substantia nigra, olfactory bulb, and locus ceruleus, as well as higher total Lewy body brain load scores when compared with non‐DBS subjects. No differences in substantia nigra pigmented neuron loss scores were found. Conclusions : STN‐DBS subjects tend to have higher alpha‐synuclein density scores, but do not have a differential loss of substantia nigra pigmented neurons. © 2016 International Parkinson and Movement Disorder Society
Teaching Neuro Images : Noninfectious cyst as an unusual complication of deep brain stimulation
Gupta, Harsh , Lyons, Mark , Mehta, Shyamal H. , Gupta, Harsh V, Lyons, Mark K

Neurology | October 31, 2016 | Volume: 87 | Issue: 18 | Pages: No page available

10.1212/wnl.0000000000003284 Get It

Peripheral Synucleinopathy in Early Parkinson's Disease: Submandibular Gland Needle Biopsy Findings
Dugger, Brittany N. , Hentz, Joseph G. , Hinni, Michael L., Driver‐Dunckley, Erika , Mehta, Shyamal, Sue, Lucia I., Duffy, Amy, Intorcia, Anthony J., Filon, Jessica, Pullen, Joel, Walker, Douglas G. , Beach, Thomas G. , Driver-Dunckley, Erika, Adler, Charles H. , Lott, David G. , Mehta, Shyamal H. , Serrano, Geidy E. , Dugger, Brittany N

Movement Disorders | January 22, 2016 | Volume: 31 | Issue: 2 | Pages: 250-256

10.1002/mds.26476 Get It

ABSTRACTIntroductionFinding a peripheral tissue biopsy site to diagnose early PD would be of value for clinical care, biomarker validation, and as research enrollment criteria. Whereas autopsy and advanced PD studies suggest that the submandibular gland is an important biopsy site, there are no studies in early PD. The aim of this study was to determine whether needle biopsy of the submandibular gland reveals Lewy type alpha‐synucleinopathy in early PD.MethodsTwenty‐five early PD (duration < 5 years) and 10 controls underwent transcutaneous needle core biopsies of the submandibular gland. Tissue was stained for phosphorylated alpha‐synuclein, reviewed blind to clinical diagnosis, and only nerve element staining was considered positive.ResultsMean (standard deviation) age was 69.5 (8.3) for the PD group, 64.8 (8.0) years for controls, and disease duration 2.6 (1.1) years. Six PD and 1 control subject had inadequate glandular tissue. Positive staining was found in 14 of 19 (74%) PD and 2 of 9 (22%) control subjects. PD‐positive and ‐negative cases did not differ clinically. Adverse events (mainly swelling and bruising) were common (77% of cases), but were minor and transient.ConclusionsSubmandibular gland needle biopsies identified phosphorylated alpha‐synuclein staining in 74% of early PD subjects. False positives may be true false positives or may represent prodromal PD. If confirmed in larger studies with eventual autopsy confirmation, the potential value of submandibular gland biopsies for early PD may be to aid in clinical trial inclusion/exclusion and eventually serve as a gold standard for biomarker studies short of autopsy confirmation. © 2016 International Parkinson and Movement Disorder Society
Simplified conversion method for unified Parkinson's disease rating scale motor examinations
Hentz, Joseph G. , Mehta, Shyamal H. , Shill, Holly A. , Driver‐Dunckley, Erika, Beach, Thomas G. , Driver‐Dunckley, Erika , Adler, Charles H.

Movement Disorders | November 17, 2015 | Volume: 30 | Issue: 14 | Pages: 1967-1970

10.1002/mds.26435 Get It

ABSTRACTBackgroundWe evaluated a simplified method for converting Unified Parkinson's Disease Rating Scale Part III Motor Examination total scores (UPDRS III) to the International Parkinson and Movement Disorder Society's (MDS) revised version of the scores.MethodsPD patients in the Arizona Study of Aging and Neurodegenerative Disorders were assessed with both scales. The accuracy of the predicted scores was assessed using regression modeling, classical intraclass correlation coefficients, and the Bland‐Altman method.ResultsThere was strong correlation between the two scores. Adding 7 points to a UPDRS III total score performed approximately as well as previously published conversion formulas (intraclass correlation: 0.96). The adjusted score is expected to be within 3 points of the MDS‐UPDRS III score 50% of the time and within 9 points 95% of the time.ConclusionsSimply adding 7 points to a UPDRS III total score provides a good approximation of the MDS‐UPDRS III total score. © 2015 International Parkinson and Movement Disorder Society
Differential spectral quantitative electroencephalography patterns between control and Parkinson's disease cohorts
Caviness, John N., Utianski, Rene L. , Hentz, Joseph G. , Beach, Thomas G. , Dugger, Brittany N. , Shill, Holly A. , Driver‐Dunckley, E. D., Mehta, Shyamal H. , Driver‐Dunckley, Erika , Sabbagh, Marwan Noel , Adler, Charles H. , Utianski, Rene L , Dugger, Brittany N

European Journal of Neurology | October 31, 2015 | Volume: 23 | Issue: 2 | Pages: 387-392

10.1111/ene.12878 Get It

Background and purposeIt is believed that progressive Lewy‐type synucleinopathy (LTS) is primarily responsible for the worsening of motor and non‐motor Parkinson's disease (PD) signs and symptoms. Characterization of quantitative electroencephalography (QEEG) abnormalities across the spectrum of LTS to PD dementia (PD‐D) may provide insight into the pathophysiology of PD cortical dysfunction. Here our enlarged EEG database was leveraged to characterize spectral QEEG abnormalities in asymptomatic autopsy‐defined groups of control participants and incidental Lewy body disease (ILBD) and three clinically defined groups of participants with PD (cognitively normal PD, mild cognitive impairment PD, and PD‐D).MethodsThe PD cohort was studied as part of the Arizona Study of Aging and Neurodegenerative Disorders (AZSAND). AZSAND utilizes its Brain and Body Donation Program to perform prospective, standardized, regular longitudinal pre‐mortem assessments until death. Resting EEG from subjects was analyzed for spectral domain QEEG measures of background rhythm frequency and global relative power in delta, theta, alpha and beta bands.ResultsThe various spectral QEEG measures showed differential changes specific to the groups compared. Important findings were background rhythm frequency showing the most pairwise differences across the groups, and this also was the only significant difference between control and ILBD. An increase in delta bandpower was characteristic of worsening cognitive deficits.ConclusionsDifferent patterns of change amongst QEEG measures across LTS and PD cognitive states suggest that they correlate with heterogeneous pathophysiologies of cortical dysfunction within the PD clinical spectrum. In addition, the biomarker application of a specific spectral QEEG measure needs to be selectively suited to its study purpose.
Defining the Eye-of-the-Tiger Sign
Mehta, Shyamal H. , Morgan, John C. , Sethi, Kapil D.

JAMA Neurology | May 11, 2015 | Volume: 72 | Issue: 5 | Pages: 606

10.1001/jamaneurol.2015.0144 Get It

Treatment of Involuntary Movements with Carbamazepine in Dystonic‐Choreoathetoid Cerebral Palsy
Mehta, Shyamal H. , Sawhney, I. M. S. , Yoganathan, Kathir, Trumble, Jill P., Morgan, John C. , Sethi, Kapil D.

Movement Disorders Clinical Practice | April 11, 2014 | Volume: 1 | Issue: 1 | Pages: 82-83

10.1002/mdc3.12002 Get It

AbstractChoreoathetoid movements are quite common in cerebral palsy (CP). This is the first report of a patient with choreoathetoid CP who was successfully treated with carbamazepine. Therefore, clinicians should try carbamazepine for involuntary movements in CP patients before pursuing other procudures.