PCOM Library / Hot Topics in Research / Internal Medicine / Neurology / Archive for "Central Nervous System Disorders"

Category: Central Nervous System Disorders

Hot Topics: New Techniques Examine Parkinson’s Damage to Heart

Jackie Werner Central Nervous System Disorders, Hot Topics in Research, Neurology

In vivo imaging of inflammation and oxidative stress in a nonhuman primate model of cardiac sympathetic neurodegeneration

Metzger JM, Moore CF, Boettcher CA, et al. In vivo imaging of inflammation and oxidative stress in a nonhuman primate model of cardiac sympathetic neurodegeneration. npj Parkinson’s Disease. 2018;4(1):22. https://doi.org/10.1038/s41531-018-0057-1.

Loss of cardiac postganglionic sympathetic innervation is a characteristic pathology of Parkinson’s disease (PD). It progresses over time independently of motor symptoms and is not responsive to typical anti-parkinsonian therapies. Cardiac sympathetic neurodegeneration can be mimicked in animals using systemic dosing of the neurotoxin 6-hydroxydopamine (6-OHDA). As in PD, 6-OHDA-induced neuronal loss is associated with increased inflammation and oxidative stress. To assess the feasibility of detecting changes over time in cardiac catecholaminergic innervation, inflammation, and oxidative stress, myocardial positron emission tomography with the radioligands [11C]meta-hydroxyephedrine (MHED), [11C]PBR28 (PBR28), and [61Cu]diacetyl-bis(N(4))-methylthiosemicarbazone (ATSM) was performed in 6-OHDA-intoxicated adult, male rhesus macaques (n = 10; 50 mg/kg i.v.). The peroxisome proliferator-activated receptor gamma (PPARγ) agonist pioglitazone, which is known to have anti-inflammatory and anti-oxidative stress properties, was administered to five animals (5 mg/kg, PO); the other five were placebo-treated. One week after 6-OHDA, cardiac MHED uptake was significantly reduced in both groups (placebo, 86% decrease; pioglitazone, 82%); PBR28 and ATSM uptake increased in both groups but were attenuated in pioglitazone-treated animals (PBR28 Treatment × Level ANOVA p < 0.002; ATSM Mann–Whitney p = 0.032). At 12 weeks, partial recovery of MHED uptake was significantly greater in the pioglitazone-treated group, dependent on left ventricle circumferential region and axial level (Treatment × Region × Level ANOVA p = 0.034); 12-week MHED uptake significantly correlated with tyrosine hydroxylase immunoreactivity across cardiac anatomy (p < 0.000002). PBR28 and ATSM uptake returned to baseline levels by 12 weeks. These radioligands thus hold potential as in vivo biomarkers of mechanisms of cardiac neurodegeneration and neuroprotection.

Hot Topics: Wristband Devices Detect Dangerous Epileptic Seizures

Jackie Werner Central Nervous System Disorders, Hot Topics in Research, Neurology

Multicenter clinical assessment of improved wearable multimodal convulsive seizure detectors

Onorati, F., Regalia, G., Caborni, C., Migliorini, M., Bender, D., et al. (2017), Multicenter clinical assessment of improved wearable multimodal convulsive seizure detectors. Epilepsia. doi:10.1111/epi.13899

Objective

New devices are needed for monitoring seizures, especially those associated with sudden unexpected death in epilepsy (SUDEP). They must be unobtrusive and automated, and provide false alarm rates (FARs) bearable in everyday life. This study quantifies the performance of new multimodal wrist-worn convulsive seizure detectors.

Methods

Hand-annotated video-electroencephalographic seizure events were collected from 69 patients at six clinical sites. Three different wristbands were used to record electrodermal activity (EDA) and accelerometer (ACM) signals, obtaining 5,928 h of data, including 55 convulsive epileptic seizures (six focal tonic–clonic seizures and 49 focal to bilateral tonic–clonic seizures) from 22 patients. Recordings were analyzed offline to train and test two new machine learning classifiers and a published classifier based on EDA and ACM. Moreover, wristband data were analyzed to estimate seizure-motion duration and autonomic responses.

Results

The two novel classifiers consistently outperformed the previous detector. The most efficient (Classifier III) yielded sensitivity of 94.55%, and an FAR of 0.2 events/day. No nocturnal seizures were missed. Most patients had <1 false alarm every 4 days, with an FAR below their seizure frequency. When increasing the sensitivity to 100% (no missed seizures), the FAR is up to 13 times lower than with the previous detector. Furthermore, all detections occurred before the seizure ended, providing reasonable latency (median = 29.3 s, range = 14.8–151 s). Automatically estimated seizure durations were correlated with true durations, enabling reliable annotations. Finally, EDA measurements confirmed the presence of postictal autonomic dysfunction, exhibiting a significant rise in 73% of the convulsive seizures.

Significance

The proposed multimodal wrist-worn convulsive seizure detectors provide seizure counts that are more accurate than previous automated detectors and typical patient self-reports, while maintaining a tolerable FAR for ambulatory monitoring. Furthermore, the multimodal system provides an objective description of motor behavior and autonomic dysfunction, aimed at enriching seizure characterization, with potential utility for SUDEP warning.

Hot Topics: Ultrasound Therapy Reduces Parkinson’s Tremors

Jackie Werner Central Nervous System Disorders, Hot Topics in Research, Neurology

Safety and Efficacy of Focused Ultrasound Thalamotomy for Patients With Medication-Refractory, Tremor-Dominant Parkinson Disease: A Randomized Clinical Trial

Bond, A. E., Shah, B. B., Huss, D. S., et al. (2017). Safety and efficacy of focused ultrasound thalamotomy for patients with medication-refractory, tremor-dominant parkinson disease: A randomized clinical trial. JAMA Neurology. doi:10.1001/jamaneurol.2017.3098

Importance  Clinical trials have confirmed the efficacy of focused ultrasound (FUS) thalamotomy in essential tremor, but its effectiveness and safety for managing tremor-dominant Parkinson disease (TDPD) is unknown.

Objective  To assess safety and efficacy at 12-month follow-up, accounting for placebo response, of unilateral FUS thalamotomy for patients with TDPD.

Design, Setting, and Participants  Of the 326 patients identified from an in-house database, 53 patients consented to be screened. Twenty-six were ineligible, and 27 were randomized (2:1) to FUS thalamotomy or a sham procedure at 2 centers from October18, 2012, to January 8, 2015. The most common reasons for disqualification were withdrawal (8 persons [31%]), and not being medication refractory (8 persons [31%]). Data were analyzed using intention-to-treat analysis, and assessments were double-blinded through the primary outcome.

Interventions  Twenty patients were randomized to unilateral FUS thalamotomy, and 7 to sham procedure. The sham group was offered open-label treatment after unblinding.

Main Outcomes and Measures  The predefined primary outcomes were safety and difference in improvement between groups at 3 months in the on-medication treated hand tremor subscore from the Clinical Rating Scale for Tremor (CRST). Secondary outcomes included descriptive results of Unified Parkinson’s Disease Rating Scale (UPDRS) scores and quality of life measures.

Results  Of the 27 patients, 26 (96%) were male and the median age was 67.8 years (interquartile range [IQR], 62.1-73.8 years). On-medication median tremor scores improved 62% (IQR, 22%-79%) from a baseline of 17 points (IQR, 10.5-27.5) following FUS thalamotomy and 22% (IQR, −11% to 29%) from a baseline of 23 points (IQR, 14.0-27.0) after sham procedures; the between-group difference was significant (Wilcoxon P = .04). On-medication median UPDRS motor scores improved 8 points (IQR, 0.5-11.0) from a baseline of 23 points (IQR, 15.5-34.0) following FUS thalamotomy and 1 point (IQR, −5.0 to 9.0) from a baseline of 25 points (IQR, 15.0-33.0) after sham procedures. Early in the study, heating of the internal capsule resulted in 2 cases (8%) of mild hemiparesis, which improved and prompted monitoring of an additional axis during magnetic resonance thermometry. Other persistent adverse events were orofacial paresthesia (4 events [20%]), finger paresthesia (1 event [5%]), and ataxia (1 event [5%]).

Conclusions and Relevance  Focused ultrasound thalamotomy for patients with TDPD demonstrated improvements in medication-refractory tremor by CRST assessments, even in the setting of a placebo response.

Hot Topics: FDA Approves First Drug For Severe Multiple Sclerosis

Jackie Werner Central Nervous System Disorders, Hot Topics in Research

FDA approves new drug to treat multiple sclerosis

Food and Drug Administration, U.S. Department of Health and Human Services. (2017). FDA approves new drug to treat multiple sclerosis. Retrieved from https://www.fda.gov/NewsEvents/Newsroom/PressAnnouncements/ucm549325.htm.

On March 28, the U.S. Food and Drug Administration approved Ocrevus (ocrelizumab) to treat adult patients with relapsing forms of multiple sclerosis (MS) and primary progressive multiple sclerosis (PPMS). This is the first drug approved by the FDA for PPMS. Ocrevus is an intravenous infusion given by a health care professional.

“Multiple sclerosis can have a profound impact on a person’s life,” said Billy Dunn, M.D., director of the Division of Neurology Products in the FDA’s Center for Drug Evaluation and Research. “This therapy not only provides another treatment option for those with relapsing MS, but for the first time provides an approved therapy for those with primary progressive MS.”