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Dive into the research topics where Cheryl Kennedy is active.

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Featured researches published by Cheryl Kennedy.


Neurology | 2011

Prevalence, sensitivity, and specificity of chronic cerebrospinal venous insufficiency in MS

Robert Zivadinov; Karen Marr; Gary Cutter; Murali Ramanathan; Rhb Benedict; Cheryl Kennedy; Makki Elfadil; A.E. Yeh; Justine Reuther; Christina Brooks; Kristin Hunt; Michelle Andrews; Ellen Carl; Michael G. Dwyer; David Hojnacki; B. Weinstock-Guttman

Background: Chronic cerebrospinal venous insufficiency (CCSVI) was recently described in patients with multiple sclerosis (MS). A subject is considered CCSVI positive if ≥2 venous hemodynamic (VH) criteria are fulfilled. Objective: To determine prevalence of CCSVI in a large cohort of patients with MS, clinically isolated syndrome (CIS), other neurologic diseases (OND), and healthy controls (HC), using specific proposed echo-color Doppler (ECD) criteria. Methods: Transcranial and extracranial ECD were carried out in 499 enrolled subjects (289 MS, 163 HC, 26 OND, 21 CIS). Prevalence rates for CCSVI were calculated in 3 ways: first, using only the subjects for whom diagnosis was certain (i.e., borderline subjects were excluded); secondly, including the borderline subjects in the “no CCSVI” group; and finally, taking into account subjects who presented any of the VH criteria. Results: CCSVI prevalence with borderline cases included in the “no CCSVI” group was 56.1% in MS, 42.3% in OND, 38.1% in CIS, and 22.7% in HC (p < 0.001). The CCSVI prevalence figures were 62.5% for MS, 45.8% for OND, 42.1% for CIS, and 25.5% for HC when borderline cases were excluded (p < 0.001). The prevalence of one or more positive VH criteria was the highest in MS (81.3%), followed by CIS (76.2%), OND (65.4%), and HC (55.2%) (p < 0.001). CCSVI prevalence was higher in patients with progressive than in nonprogressive MS (p = 0.004). Conclusions: Our findings are consistent with an increased prevalence of CCSVI in MS but with modest sensitivity/specificity. Our findings point against CCSVI having a primary causative role in the development of MS.


NeuroImage | 2012

Abnormal subcortical deep-gray matter susceptibility-weighted imaging filtered phase measurements in patients with multiple sclerosis: a case-control study.

Robert Zivadinov; Mari Heininen Brown; Claudiu Schirda; Guy Umberto Poloni; Niels Bergsland; Christopher Magnano; Jacqueline Durfee; Cheryl Kennedy; Ellen Carl; Jesper Hagemeier; Ralph H. B. Benedict; Bianca Weinstock-Guttman; Michael G. Dwyer

OBJECTIVE To investigate abnormal phase on susceptibility-weighted imaging (SWI)-filtered phase images indicative of iron content, in subcortical deep-gray matter (SDGM) of multiple sclerosis (MS) patients and healthy controls (HC), and to explore its relationship with MRI outcomes. METHODS 169 relapsing-remitting (RR) and 64 secondary-progressive (SP) MS patients, and 126 age- and sex-matched HC were imaged on a 3T scanner. Mean phase of the abnormal phase tissue (MP-APT), normal phase tissue volume (NPTV) and normalized volume were determined for total SDGM, caudate, putamen, globus pallidus, thalamus, pulvinar nucleus of thalamus (PVN), hippocampus, amygdala, nucleus accumbens, red nucleus and substantia nigra. 63 HC were used for establishment of normal reference phase values, while additional 63 HC were used for blinded comparisons with MS patients. RESULTS Increased MP-APT, decreased normalized volume and decreased NPTV were detected in total SDGM, caudate, putamen, globus pallidus, thalamus and PVN in MS patients compared to HC (p<.0004). MS patients also showed decreased volume in hippocampus (<.0001) and decreased NPTV in the hippocampus, amygdala and accumbens (<.0004). SPMS patients had increased MP-APT, decreased volume and decreased NPTV in total SDGM, caudate and amygdala compared to RRMS (p<.005), while individual measure differences were also detected in putamen, thalamus, hippocampus and accumbens (p<.006). RRMS patients showed a significant relationship between increased MP-APT and increased lesion burden and more advanced brain atrophy (p<.004). CONCLUSIONS Abnormal phase, indicative of higher iron content was significantly increased in MS patients compared to HC, and was related to more severe lesion burden and brain atrophy.


Radiology | 2011

Use of MR venography for characterization of the extracranial venous system in patients with multiple sclerosis and healthy control subjects.

Robert Zivadinov; Alexandra Lopez-Soriano; Bianca Weinstock-Guttman; Claudiu Schirda; Christopher Magnano; Kresimir Dolic; Cheryl Kennedy; Christina Brooks; Justine Reuther; Kristin Hunt; Michelle Andrews; Michael G. Dwyer; David Hojnacki

PURPOSE To investigate the differences in the extracranial venous system in patients with multiple sclerosis (MS) and healthy control (HC) subjects by using magnetic resonance (MR) venography. MATERIALS AND METHODS This HIPAA-compliant, prospective study was approved by the local institutional review board, and all participants gave informed consent. Fifty-seven patients, 41 (72%) with relapsing-remitting MS and 16 (28%) with secondary-progressive MS, and 21 HC subjects were imaged with a 3-T MR unit by using two-dimensional (2D) time-of-flight (TOF) and three-dimensional (3D) time-resolved imaging of contrast kinetics (TRICKS) sequences. In addition, six MS patients and six HC subjects underwent two sequential MR venographic examinations during 1 week to test image-reimage reproducibility. The morphologic features of internal jugular vein flow were classified as absent, pinpoint, flattened, crescentic, or ellipsoidal flow. Only absent and pinpoint flow were considered abnormal. The flow of the vertebral veins was classified as absent or present. The prominence of collateral neck veins and venous asymmetries between the left and right sides were assessed. Differences among groups were tested with a two-tailed Mann-Whitney two-sample rank-sum test. RESULTS No significant differences in morphologic features of flow in the internal jugular veins and vertebral veins were found between MS patients and HC subjects in any of the examined MR venographic parameters. No differences in asymmetry or prominence were found between MS patients and HC subjects. There was modest agreement (κ = 0.67) between 2D TOF and 3D TRICKS sequences. Image-reimage reproducibility showed modest agreement (κ = 0.66) for 2D TOF and low agreement for 3D TRICKS (κ = 0.33). CONCLUSION No significant differences in the extracranial venous systems between MS patients and HC subjects were detected by using MR venography. Standardized guidelines are needed to define parameters for the presence of venous anomalies.


European Journal of Vascular and Endovascular Surgery | 2012

Venous Angioplasty in Patients with Multiple Sclerosis: Results of a Pilot Study

Paolo Zamboni; Roberto Galeotti; Bianca Weinstock-Guttman; Cheryl Kennedy; Fabrizio Salvi; Robert Zivadinov

OBJECTIVES Chronic cerebrospinal venous insufficiency (CCSVI) is associated with multiple sclerosis (MS). The objective of the study was to see if percutaneous transluminal angioplasty (PTA) of duplex-detected lesions, of the internal jugular and/or azygous veins, was safe, burdened by a significant restenosis rate, and whether there was any evidence that treatment reduced MS disease activity. DESIGN This was a case-control study. MATERIALS We studied 15 patients with relapsing-remitting MS and duplex-detected CCSVI. METHODS Eight patients had PTA in addition to medical therapy (immediate treatment group (ITG)), whereas seven had treatment with PTA after 6 months of medical therapy alone (delayed treatment group (DTG)). RESULTS No adverse events occurred. At 1 year, there was a restenosis rate of 27%. Overall, PTA was followed by a significant improvement in functional score compared with baseline (p < 0.02). The annualised relapse rate was 0.12% in the ITG compared with 0.66% in the DTG (p = NS). Magnetic resonance imaging (MRI) blindly demonstrates a trend for fewer T2 lesions in the ITG (p = 0.081), corresponding to a 10% decrease in the ITG compared with a 23% increase in the DTG over the first 6 months of the study. CONCLUSIONS This study further confirms the safety of PTA treatment in patients with CCSVI associated with MS. The results, despite the significant rate of restenosis, are encouraging and warrant a larger multicentre double-blinded, randomised study.


BMC Medicine | 2011

Hypoperfusion of brain parenchyma is associated with the severity of chronic cerebrospinal venous insufficiency in patients with multiple sclerosis: a cross-sectional preliminary report

Paolo Zamboni; Erica Menegatti; Bianca Weinstock-Guttman; Michael G. Dwyer; Claudiu Schirda; Anna Maria Malagoni; David Hojnacki; Cheryl Kennedy; Ellen Carl; Niels Bergsland; Christopher Magnano; Ilaria Bartolomei; Fabrizio Salvi; Robert Zivadinov

BackgroundSeveral studies have reported hypoperfusion of the brain parenchyma in multiple sclerosis (MS) patients. We hypothesized a possible relationship between abnormal perfusion in MS and hampered venous outflow at the extracranial level, a condition possibly associated with MS and known as chronic cerebrospinal venous insufficiency (CCSVI).MethodsWe investigated the relationship between CCSVI and cerebral perfusion in 16 CCSVI MS patients and 8 age- and sex-matched healthy controls. Subjects were scanned in a 3-T scanner using dynamic susceptibility, contrast-enhanced, perfusion-weighted imaging. Cerebral blood flow (CBF), cerebral blood volume (CBV) and mean transit time (MTT) were measured in the gray matter (GM), white matter (WM) and the subcortical GM (SGM). The severity of CCSVI was assessed according to the venous hemodynamic insufficiency severity score (VHISS) on the basis of the number of venous segments exhibiting flow abnormalities.ResultsThere was a significant association between increased VHISS and decreased CBF in the majority of examined regions of the brain parenchyma in MS patients. The most robust correlations were observed for GM and WM (r = -0.70 to -0.71, P < 0.002 and P corrected = 0.022), and for the putamen, thalamus, pulvinar nucleus of thalamus, globus pallidus and hippocampus (r = -0.59 to -0.71, P < 0.01 and P corrected < 0.05). No results for correlation between VHISS and CBV or MTT survived multiple comparison correction.ConclusionsThis pilot study is the first to report a significant relationship between the severity of CCSVI and hypoperfusion in the brain parenchyma. These preliminary findings should be confirmed in a larger cohort of MS patients to ensure that they generalize to the MS population as a whole. Reduced perfusion could contribute to the known mechanisms of virtual hypoxia in degenerated axons.


Journal of Psychoactive Drugs | 2004

Club Drugs: Reasons for and Consequences of Use

Kathleen A. Parks; Cheryl Kennedy

Abstract This preliminary descriptive study was designed to assess the reasons, primary contexts, and consequences (physical, psychological, lifestyle) of club drug use in a sample of young adults in a mid-size U.S. city. Fifty young adults (18 to 30 years old) reported on their use of club drugs (Ecstasy, GHB, ketamine, Rohypnol®, methamphetamine, LSD) in face-to-face interviews that included quantitative and qualitative measures. Ecstasy was the most frequently used club drug followed by ketamine, LSD and methamphetamine. All of the participants reported using club drugs to “experiment” and most reported using these drugs to feel good and enhance social activities. Club drugs were frequently used at raves, in bars or clubs, and at home with friends. An average of 16 negative physical, psychological, and lifestyle consequences were reported for club drug use. Despite substantial negative consequences, participants perceived several positive consequences of regular recreational club drug use. These findings corroborate descriptions of club drug use in other countries (e.g., Australia, United Kingdom) and provide additional information on perceived positive consequences that users experience with club drug use. Further exploration of the reasons and positive consequences that are associated with use of each of the club drugs may provide important information on the growing trend in use of these drugs.


Journal of Neurology, Neurosurgery, and Psychiatry | 2015

Cardiovascular risk factors are associated with increased lesion burden and brain atrophy in multiple sclerosis

Natalie Kappus; Bianca Weinstock-Guttman; Jesper Hagemeier; Cheryl Kennedy; Rebecca Melia; Ellen Carl; Deepa P. Ramasamy; Mariya Cherneva; Jacqueline Durfee; Niels Bergsland; Michael G. Dwyer; Channa Kolb; David Hojnacki; Murali Ramanathan; Robert Zivadinov

Background Cardiovascular (CV) risk factors have been associated with changes in clinical outcomes in patients with multiple sclerosis (MS). Objectives To investigate the frequency of CV risks in patients with MS and their association with MRI outcomes. Methods In a prospective study, 326 patients with relapsing–remitting MS and 163 patients with progressive MS, 61 patients with clinically isolated syndrome (CIS) and 175 healthy controls (HCs) were screened for CV risks and scanned on a 3T MRI scanner. Examined CV risks included hypertension, heart disease, smoking, overweight/obesity and type 1 diabetes. MRI measures assessed lesion volumes (LVs) and brain atrophy. Association between individual or multiple CV risks and MRI outcomes was examined adjusting for age, sex, race, disease duration and treatment status. Results Patients with MS showed increased frequency of smoking (51.7% vs 36.5%, p=0.001) and hypertension (33.9% vs 24.7%, p=0.035) compared with HCs. In total, 49.9% of patients with MS and 36% of HCs showed ≥2 CV risks (p=0.003), while the frequency of ≥3 CV risks was 18.8% in the MS group and 8.6% in the HCs group (p=0.002). In patients with MS, hypertension and heart disease were associated with decreased grey matter (GM) and cortical volumes (p<0.05), while overweight/obesity was associated with increased T1-LV (p<0.39) and smoking with decreased whole brain volume (p=0.049). Increased lateral ventricle volume was associated with heart disease (p=0.029) in CIS. Conclusions Patients with MS with one or more CV risks showed increased lesion burden and more advanced brain atrophy.


Journal of Magnetic Resonance Imaging | 2012

Iron deposition in multiple sclerosis lesions measured by susceptibility-weighted imaging filtered phase: A case control study

Jesper Hagemeier; M. Heininen-Brown; Guy Umberto Poloni; Niels Bergsland; Christopher Magnano; Jacqueline Durfee; Cheryl Kennedy; Ellen Carl; Bianca Weinstock-Guttman; Michael G. Dwyer; Robert Zivadinov

To investigate phase lesions identified on susceptibility‐weighted imaging (SWI)‐filtered phase images in patients with multiple sclerosis (MS), clinically isolated syndrome (CIS) and healthy controls (HC). To relate phase lesion characteristics to other clinical and MRI outcomes.


BMC Neurology | 2011

Decreased brain venous vasculature visibility on susceptibility-weighted imaging venography in patients with multiple sclerosis is related to chronic cerebrospinal venous insufficiency

Robert Zivadinov; Guy Umberto Poloni; Karen Marr; Claudiu Schirda; Christopher Magnano; Ellen Carl; Niels Bergsland; David Hojnacki; Cheryl Kennedy; Clive B. Beggs; Michael G. Dwyer; Bianca Weinstock-Guttman

BackgroundThe potential pathogenesis between the presence and severity of chronic cerebrospinal venous insufficiency (CCSVI) and its relation to clinical and imaging outcomes in brain parenchyma of multiple sclerosis (MS) patients has not yet been elucidated. The aim of the study was to investigate the relationship between CCSVI, and altered brain parenchyma venous vasculature visibility (VVV) on susceptibility-weighted imaging (SWI) in patients with MS and in sex- and age-matched healthy controls (HC).Methods59 MS patients, 41 relapsing-remitting and 18 secondary-progressive, and 33 HC were imaged on a 3T GE scanner using pre- and post-contrast SWI venography. The presence and severity of CCSVI was determined using extra-cranial and trans-cranial Doppler criteria. Apparent total venous volume (ATVV), venous intracranial fraction (VIF) and average distance-from-vein (DFV) were calculated for various vein mean diameter categories: < .3 mm, .3-.6 mm, .6-.9 mm and > .9 mm.ResultsCCSVI criteria were fulfilled in 79.7% of MS patients and 18.2% of HC (p < .0001). Patients with MS showed decreased overall ATVV, ATVV of veins with a diameter < .3 mm, and increased DFV compared to HC (all p < .0001). Subjects diagnosed with CCSVI had significantly increased DFV (p < .0001), decreased overall ATVV and ATVV of veins with a diameter < .3 mm (p < .003) compared to subjects without CCSVI. The severity of CCSVI was significantly related to decreased VVV in MS (p < .0001) on pre- and post-contrast SWI, but not in HC.ConclusionsMS patients with higher number of venous stenoses, indicative of CCSVI severity, showed significantly decreased venous vasculature in the brain parenchyma. The pathogenesis of these findings has to be further investigated, but they suggest that reduced metabolism and morphological changes of venous vasculature may be taking place in patients with MS.


American Journal of Neuroradiology | 2012

Iron deposition on SWI-filtered phase in the subcortical deep gray matter of patients with clinically isolated syndrome may precede structure-specific atrophy.

Jesper Hagemeier; Bianca Weinstock-Guttman; Niels Bergsland; M. Heininen-Brown; Ellen Carl; Cheryl Kennedy; Christopher Magnano; David Hojnacki; Michael G. Dwyer; Robert Zivadinov

BACKGROUND AND PURPOSE: Increasing evidence suggests that iron deposition is present in the later stages of MS. In this study we examined abnormal phase values, indicative of increased iron content on SWI-filtered phase images of the SDGM in CIS patients and HC. We also examined the association of abnormal phase with conventional MR imaging outcomes at first clinical onset. MATERIALS AND METHODS: Forty-two patients with CIS (31 female, 11 male) and 65 age and sex-matched HC (41 female, 24 male) were scanned on a 3T scanner. Mean age was 40.1 (SD = 10.4) years in patients with CIS, and 42.8 (SD = 14) years in HC, while mean disease duration was 1.2 years (SD = 1.3) in patients with CIS. MP-APT, NPTV, and normalized volume measurements were derived for all SDGM structures. Parametric and nonparametric group-wise comparisons were performed, and associations were determined with other MR imaging metrics. RESULTS: Patients with CIS had significantly increased MP-APT (P = .029) and MP-APT volume (P = .045) in the pulvinar nucleus of the thalamus compared with HC. Furthermore, the putamen (P = .004), caudate (P = .035), and total SDGM (P = .048) displayed significant increases in MP-APT volume, while MP-APT was also significantly increased in the putamen (P = .029). No global or regional volumetric MR imaging differences were found between the study groups. Significant correlations were observed between increased MP-APT volumes of total SDGM, caudate, thalamus, hippocampus, and substantia nigra with white matter atrophy and increased T2 lesion volume (P < .05). CONCLUSION: Patients with CIS showed significantly increased content and volume of iron, as determined by abnormal SWI-phase measurement, in the various SDGM structures, suggesting that iron deposition may precede structure-specific atrophy.

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Robert Zivadinov

State University of New York System

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Ellen Carl

State University of New York System

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Bianca Weinstock-Guttman

State University of New York System

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Michael G. Dwyer

State University of New York System

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David Hojnacki

State University of New York System

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Niels Bergsland

State University of New York System

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Jesper Hagemeier

State University of New York System

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Karen Marr

State University of New York System

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Deepa P. Ramasamy

State University of New York System

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