Neurological Effects of Stimulants and Hallucinogens.

In this article, we will discuss the history, pharmacodynamics, and neurotoxicity of psychostimulants and hallucinogens. The drugs discussed are widely used and have characteristic toxidromes and potential for neurological injuries with which the practicing clinician should be familiar. Psychostimulants are a class of drugs that includes cocaine, methamphetamine/amphetamines, and cathinones, among others, which produce a crescendoing euphoric high.

Opioid-Associated Nervous System Injuries.

With the rise of the opioid epidemic, the practicing neurologist must recognize the patterns of a growing number of opioid-associated neurological injuries. This is in addition to the classic toxidrome of miosis, altered mental status, and respiratory depression, which must never be overlooked, as it is reversible and potentially lifesaving. Several other idiosyncratic syndromes due to opioid-related nervous system insults are defined by their characteristic imaging findings and portend variable functional recovery.

The Impact of Drop Test Conditions on Brain Strain Location and Severity: A Novel Approach Using a Deep Learning Model.

In contact sports such as rugby, players are at risk of sustaining traumatic brain injuries (TBI) due to high-intensity head impacts that generate high linear and rotational accelerations of the head. Previous studies have established a clear link between high-intensity head impacts and brain strains that result in concussions. This study presents a novel approach to investigating the effect of a range of laboratory controlled drop test parameters on regional peak and mean maximum principal strain (MPS) predictions within the brain using a trained convolutional neural network (CNN).

Substance Use and the Nervous System.

Objective: This article informs and updates the practicing neurologist on the current landscape of known neurologic injuries linked to the use of illicit drugs, focusing on emerging agents.

Latest Developments: Synthetic opioids such as fentanyl and similar derivatives have exploded in prevalence, becoming the leading cause of overdose fatalities. The higher potency of synthetic opioids compared with semisynthetic and nonsynthetic opiates poses an increased risk for unintentional overdose when found as an adulterant in other illicit drug supplies such as heroin.

Acute Ischemic Stroke Presentation Masked by Falsely Localizing Motor Seizure: A Clinical Case Series.

In this case series, we describe a novel observation in which 4 patients with acute ischemic stroke secondary to large vessel occlusion and no history of seizure present with focal seizure activity localizable to a chronic, contralateral infarct. The explanation for this phenomenon is unknown but may be due to a combination of effects involving disrupted interhemispheric inhibitory connections and epileptogenic changes involving chronically infarcted tissue.

Drop Test Kinematics Using Varied Impact Surfaces and Head/Neck Configurations for Rugby Headgear Testing.

World Rugby employs a specific drop test method to evaluate headgear performance, but almost all researchers use a different variation of this method. The aim of this study was, therefore, to quantify the differences between variations of the drop testing method using a Hybrid III headform and neck in the following impact setups: (1) headform only, with a flat steel impact surface, approximating the World Rugby method, (2 and 3) headform with and without a neck, respectively, onto a flat MEP pad impact surface, and (4) headform and neck, dropped onto an angled MEP pad impact surface. Each variation was subject to drop heights of 75-600 mm across three orientations (forehead, side, and rear boss).

Novel likely pathogenic variant in primary familial brain calcification.

A woman in her 30s was referred to our neurology outpatient clinic following an incidental finding of significant bilateral and symmetric basal ganglia, thalamic, cerebellar and subcortical white matter calcification on brain CT and MRI. A diagnosis of asymptomatic primary familial brain calcification (PFBC) was made. Targeted genetic testing revealed a likely pathogenic variant in the gene, the most common gene in which pathogenic variants have been implicated in PFBC.

Laboratory Validation of Instrumented Mouthguard for Use in Sport.

Concussion is an inherent risk of participating in contact, combat, or collision sports, within which head impacts are numerous. Kinematic parameters such as peak linear and rotational acceleration represent primary measures of concussive head impacts. The ability to accurately measure and categorise such impact parameters in real time is important in health and sports performance contexts.

MuSK Myasthenia Gravis Presenting with Bilateral Vocal Cord Abduction Paresis: A Case Report and Literature Review.

Introduction: Approximately 39% to 49% of patients with previously diagnosed acetylcholine receptor antibody-negative myasthenia gravis have been found to be muscle-specific tyrosine kinase (MuSK) antibody positive. These patients have a presentation that typically includes oculobulbar weakness, poorer response to cholinesterase inhibitors, and higher risk for acute clinical decompensation that necessitates plasma exchange. MuSK patients can require more aggressive maintenance immunosuppression earlier-on to maintain stability, often with rituximab.

Autonomic Testing Profiles in Scans without Evidence of Dopaminergic Deficit (SWEDD).

Background: Scans without evidence of dopaminergic deficit (SWEDDS) on 123I-FP-CIT SPECT (DAT) can occur in patients with clinical evidence of Parkinsonism. In this patient population, autonomic function testing may elucidate the underlying clinical disorder.

Objective: To evaluate SWEDD patients undergoing autonomic testing and determine the severity and pattern of autonomic dysfunction.

Drugs of Abuse and the Nervous System.

Purpose Of Review: This article discusses the neurologic complications of traditional, nontraditional, and emerging drugs of abuse.

Recent Findings: The manufacture, distribution, and use of so-called designer drugs are increasing. These agents can induce dramatic neurologic manifestations and can evade identification on conventional drug-screening assays.

An unusual presentation of late-onset Alexander's disease with slow orthostatic tremor and a novel GFAP variant.

Alexander disease (AxD) is a leukodystrophy, described in infantile, juvenile and adult onset forms, due to mutations in the glial fibrillary acid protein (GFAP) gene. Adult-onset AxD (AOAD) has a range of clinical and radiographic phenotypes with the oldest reported onset in the seventh decade.We report a case of AOAD, with onset in the eighth decade, presenting with slow variant orthostatic tremor, which has not been previously described.

A Case of cutaneous large B-cell lymphoma during treatment of multiple sclerosis with fingolimod.

The authors report a case of a 69-year-old woman with multiple sclerosis treated with fingolimod for duration of over one year who subsequently developed cutaneous large B cell lymphoma. There are few reported cases of lymphoma associated with fingolimod treatment for multiple sclerosis, but rates are higher than expected in the general population. The authors hope to promote awareness of the potential risk of this medication so that more diligent disease surveillance can be performed by both prescribing practitioners of fingolimod and their patients who receive it.

Test characteristics of point-of-care ultrasonography for the diagnosis of acute posterior ocular pathology.

Objectives: The objective of this study was to determine the test characteristics of point-of-care ultrasonography (POCUS) for the diagnosis of retinal tear (RT), retinal detachment (RD), posterior vitreous detachment (PVD), and vitreous hemorrhage (VH).

Design: A prospective observation study on a convenience sample of patients presenting to a tertiary care emergency general ophthalmology clinic was performed.

Participants: Adult patients with acute flashes/floaters or new visual field defects were included (n = 62).

Efficacy of SLO-Microperimetry and Humphrey for evaluating macular sensitivity changes in advanced glaucoma.

Objective: To compare the efficacy of scanning laser ophthalmoscope microperimetry (SLO-MP) and Humphrey visual fields in detecting macular sensitivity changes in advanced glaucoma.

Design: Prospective cohort study.

Participants: 25 patients with advanced primary open angle glaucoma and 2 consecutive abnormal Humphrey 10-2 SITA Standard visual field tests.

Medication discrepancies identified at time of hospital discharge in a geriatric population.

Background: It has been reported that 14.1% of geriatric patients experience ≥1 medication discrepancies after hospitalization.

Objective: The goal of this study was to identify and characterize discharge medication list discrepancies among geriatric patients and to describe characteristics associated with discrepancies.