A phase I trial of accelerated intermittent theta burst rTMS for amnestic MCI.

Background: Emerging evidence suggests that repetitive transcranial magnetic stimulation (rTMS) enhances cognition in mild cognitive impairment (MCI). Accelerated intermittent theta burst stimulation (iTBS) rTMS protocols are promising as they substantially reduce burden by shortening the treatment course, but the safety, feasibility, and acceptability of iTBS have not been established in MCI.

Methods: 24 older adults with amnestic MCI (aMCI) due to possible Alzheimer's disease enrolled in a phase I trial of open-label accelerated iTBS to the left dorsolateral prefrontal cortex (8 stimulation sessions of 600 pulses of iTBS/day for 3 days).

Template MRI scans reliably approximate individual and group-level tES and TMS electric fields induced in motor and prefrontal circuits.

Background: Electric field (E-field) modeling is a valuable method of elucidating the cortical target engagement from transcranial magnetic stimulation (TMS) and transcranial electrical stimulation (tES), but it is typically dependent on individual MRI scans. In this study, we systematically tested whether E-field models in template MNI-152 and Ernie scans can reliably approximate group-level E-fields induced in = 195 individuals across 5 diagnoses (healthy, alcohol use disorder, tobacco use disorder, anxiety, depression).

Methods: We computed 788 E-field models using the CHARM-SimNIBS 4.

Safety of MRI in the localization of implanted intracranial electrodes for refractory epilepsy.

Background And Purpose: This is an observational study to evaluate the safety of magnetic resonance imaging (MRI) to localize subdural grids and depth electrodes in patients with refractory epilepsy using a 1.5 Tesla MR scanner.

Methods: We implemented an optimized MRI protocol providing adequate image quality for the assessment of subdural grids and depth electrodes, while minimizing the specific absorption rate (SAR).

Altered cerebral perfusion in response to chronic mild hypercapnia and head-down tilt Bed rest as an analog for Spaceflight.

Purpose: Following prolonged stays on the International Space Station (ISS), some astronauts exhibit visual acuity changes, ophthalmological findings, and mildly elevated intracranial pressures as part of a novel process called spaceflight-associated neuro-ocular syndrome (SANS). To determine the pathophysiology of SANS, NASA conducted a multi-investigator study in which 11 healthy participants underwent head-down tilt bed rest, mimicking microgravity-induced cephalad fluid shifts, combined with elevated ambient CO levels similar to those on the ISS (HDT+CO). As part of that study, we examined the effects of HDT+CO on cerebral perfusion.

Juvenile xanthogranuloma of the subdural spaces mimicking chronic hematoma with positive FDG uptake on PET: case report.

The authors report an unusual presentation of juvenile xanthogranuloma (JXG), a non-Langerhans cell histiocytosis of infancy and early childhood. This entity typically presents as a cutaneous head or neck nodule but can manifest with more systemic involvement including in the central nervous system. However, currently there is limited information regarding specific imaging features differentiating JXG from other neuropathological entities, with diagnosis typically made only after tissue sampling.

Primary Central Nervous System Posttransplant Lymphoproliferative Disorder After Kidney Transplant.

Primary central nervous system posttransplant lymphoproliferative disorder is a rare complication of solid organ transplantation, with increasing incidence in children given a steady rise in pediatric solid organ transplants. Given similar imaging appearance to many opportunistic infections, a high degree of awareness is required for prompt and early diagnosis. We report a case of primary central nervous system posttransplant lymphoproliferative disorder presenting as a single rim enhancing lesion with central restricted diffusion mimicking an intracranial abscess.

Spaceflight-Associated Changes in the Opacification of the Paranasal Sinuses and Mastoid Air Cells in Astronauts.

Importance: Head congestion is one of the most common somatic symptoms experienced by astronauts during spaceflight; however, changes in the opacification of the paranasal sinuses or mastoid air cells in astronauts have not been adequately studied.

Objectives: To quantify preflight to postflight changes in the opacification of the paranasal sinuses and mastoid air cells in Space Shuttle astronauts and International Space Station (ISS) astronauts and to assess whether there are differences between the 2 groups of astronauts.

Design, Setting, And Participants: This cohort study examined preflight and postflight head magnetic resonance images (MRIs) of 35 astronauts who had participated in either a short-duration (≤30 days) Space Shuttle mission or a long-duration (>30 days) ISS mission and had undergone both preflight and postflight MRI.

A Helpful Tool in Diagnosing Stroke Mimics: Arterial Spin Labeled Perfusion Magnetic Resonance Imaging.

Background: Prompt and effective management of acute ischemic stroke in the emergency setting requires a high level of suspicion and accurate diagnosis. Conversely, identifying stroke mimics can be challenging, given the similarity of their clinical symptomatology, the necessary rapid assessment and triage, and the overall frenetic pace inherent in the goal of rapid thrombolysis ("time is brain").

Case Report: We describe a case that involves an elderly patient with acute hemiplegia and dysarthria.

Effects of Spaceflight on Astronaut Brain Structure as Indicated on MRI.

Background: There is limited information regarding the effects of spaceflight on the anatomical configuration of the brain and on cerebrospinal fluid (CSF) spaces.

Methods: We used magnetic resonance imaging (MRI) to compare images of 18 astronauts' brains before and after missions of long duration, involving stays on the International Space Station, and of 16 astronauts' brains before and after missions of short duration, involving participation in the Space Shuttle Program. Images were interpreted by readers who were unaware of the flight duration.

Light-induced Hemiplegia, an Atypical Case of Retinal Steal Syndrome.

Atherosclerosis affecting the carotid arteries accounts for up to 20% of ischemic strokes 1. The clinical effects of atherosclerotic occlusive disease vary according to multiple factors, one of which is collateral circulation. In response to a chronic decrease in cerebral perfusion from atherosclerotic occlusion, alternative flow pathways, or collaterals, develop in a variety of patterns.

Acute Preoperative Infarcts and Poor Cerebrovascular Reserve Are Independent Risk Factors for Severe Ischemic Complications following Direct Extracranial-Intracranial Bypass for Moyamoya Disease.

Background And Purpose: Severe ischemic changes are a rare but devastating complication following direct superficial temporal artery to MCA bypass in patients with Moyamoya disease. This study was undertaken to determine whether preoperative MR imaging and/or cerebrovascular reserve assessment by using reference standard stable xenon-enhanced CT could predict such complications.

Materials And Methods: Among all adult patients undergoing direct bypass at our institution between 2005 and 2010 who received a clinically interpretable xenon-enhanced CT examination, we identified index cases (patients with >15-mL postoperative infarcts) and control cases (patients without postoperative infarcts and without transient or permanent ischemic symptoms).