Task-Based and Resting-State Functional MRI in Observing Eloquent Cerebral Areas Personalized for Epilepsy and Surgical Oncology Patients: A Review of the Current Evidence.

Functional magnetic resonance imaging (fMRI) is among the newest techniques of advanced neuroimaging that offer the opportunity for neuroradiologists, neurophysiologists, neuro-oncologists, and neurosurgeons to pre-operatively plan and manage different types of brain lesions. Furthermore, it plays a fundamental role in the personalized evaluation of patients with brain tumors or patients with an epileptic focus for preoperative planning. While the implementation of task-based fMRI has increased in recent years, the existing resources and evidence related to this technique are limited. We have, therefore, conducted a comprehensive review of the available resources to compile a detailed resource for physicians who specialize in managing patients with brain tumors and seizure disorders. This review contributes to the existing literature because it highlights the lack of studies on fMRI and its precise role and applicability in observing eloquent cerebral areas in surgical oncology and epilepsy patients, which we believe is underreported. Taking these considerations into account would help to better understand the role of this advanced neuroimaging technique and, ultimately, improve patient life expectancy and quality of life.

Therapeutic Dilemma of Wake-up Stroke: Clinical and Brain Imaging Characteristics and Reperfusion as a Treatment Option.

Objective: Wake-up stroke (WUS) comprises a significant proportion of ischemic strokes. However, due to unclear onset, these patients are often not considered for reperfusion therapy. The objective of this study was to investigate the clinical and imaging differences between WUS patients and those with clear-onset stroke, documenting any sex, age, or risk factor predilection for WUS.Methods: This prospective observational cohort study used an ongoing stroke registry to identify patients with acute ischemic stroke admitted to a hospital in Saudi Arabia within 5 days of symptom onset from April 2018 to March 2020. Patients were classified into 2 groups: WUS and clear-onset stroke.Results: Among 645 patients, 448 met the criteria for acute ischemic stroke and were included in the study. WUS was identified in 112 (25%) patients. There were no differences in sex or median age between the 2 groups. Diabetes mellitus, hypertension, and dyslipidemia were higher in the WUS group, while atrial fibrillation, history of stroke and epilepsy were higher in the clear-onset stroke group. Bihemispheric stroke was higher in the clear-onset stroke group than in the WUS group (6.0% vs 2.7%).Conclusions: Only minor dissimilarities between clinical and radiologic features of WUS and clear-onset stroke were found. Circadian patterns of stroke onset were observed in both groups. Stroke was more likely to occur during waking than during sleep, and a diurnal pattern of common occurrence during the morning was documented. Recognition of the acceptable timeframe for acute reperfusion therapy in unwitnessed strokes is crucial so that thrombolytic treatment can be started for these patients.