Awake Craniotomy for Gliomas in the Non-Dominant Right Hemisphere: A Comprehensive Review.

Awake surgery has become a standard practice for managing diffuse low-grade gliomas (LGGs), particularly in eloquent brain areas, and is established as a gold standard technique for left-dominant-hemisphere tumors. However, the intraoperative monitoring of functions in the right non-dominant hemisphere (RndH) is often neglected, highlighting the need for a better understanding of neurocognitive testing for complex functions in the right hemisphere. This article aims to comprehensively review the current literature on the benefits of awake craniotomy in gliomas of the non-dominant right hemisphere. A systematic review was conducted using the PubMed and ScienceDirect databases with keywords such as "right hemisphere", "awake surgery", "direct electrical brain stimulation and mapping", and "glioma". The search focused on anatomical and surgical aspects, including indications, tools, and techniques of awake surgery in right cerebral hemisphere gliomas. The literature search identified 74 sources, including original articles, books, monographs, and review articles. Two papers reported large series of language assessment cases in 246 patients undergoing awake surgery with detailed neurological semiology and mapping techniques, while the remaining studies were predominantly neuroradiological and neuroimaging in nature. Awake craniotomy for non-dominant-hemisphere gliomas is an essential tool. The term "non-dominant" should be revised, as this hemisphere contributes significantly to essential cognitive functions in the human brain.

Simplifying the Technique of Awake Brain Surgery in a Condition of Less Equipped Neurosurgical Institution in Uzbekistan.

Currently, awake craniotomy (AC) is one of the most often employed procedures to map and resect tumors in eloquent brain areas, avoiding the use of general anesthesia (GA) and thereby reducing anesthesia-related complications and cost of surgery. Resource limitations are one of the basic reasons for avoiding AC in low- and middle-income countries (LMICs). The aim of this study is to describe the simplified protocol of awake brain surgery that can be implemented in a limited financial setting in LMICs and to share our first experience. Twenty-five patients diagnosed with tumor of the left frontotemporal lobes, all involving Broca's and Wernicke's areas, were operated on using AC. Brain mapping was executed using mono- and bipolar direct electrical stimulation including cortical and subcortical (axonal) mapping profiles, investigating basically cortical language centers. Neither neuronavigation nor intraoperative magnetic resonance imaging (MRI) was utilized due to financial constraints. AC was performed successfully in 23 of 25 patients, achieving a near-total resection in 16 (69.5%) patients, subtotal resection in 4 patients (17.39%) patients, and partial resection in 3 (13.04%) patients. In two patients, due to psychological instability-agitation and fear during the awake phase-speech test was not technically possible, so they were reintubated by giving them GA. There was no mortality in the early or postoperative period. In spite of the absence of advanced pre- and intraoperative technologies such as intraoperative MRI and navigation systems, AC can be safely performed in LMICs. These tools along with intraoperative cortical mapping and language testing can guarantee better surgical outcomes and quality of life. However, our study confirms that omitting these tools does not make a huge difference in getting good results with AC and that AC is not absolutely impossible. AC can be performed successfully, preserving eloquent brain areas, with minimum and basic set of the armamentarium like system for cortical and subcortical intraoperative neurostimulation which provides cortical/subcortical brain mapping.

Unilateral Fenestrated A1 Segment of Anterior Cerebral Artery Multiple Aneurysms: Case Reports and Literature Review.

The fenestration of the cerebral arteries is infrequent anomaly mostly occurring in the posterior communicating artery, the vertebral artery, the basilar artery, and the middle cerebral artery.[1] We report a case of unilateral A1 fenestration associated saccular aneurysm, focusing on its features of surgical treatment.

The Importance of Measuring Mamillopontine Distance as a Diagnostic Criterion of Hydrocephalus Degrees.

OBJECTIVES: The occurrence of obstructive hydrocephalus (ObH) as sequelae of deep midline brain tumors (third and lateral ventricles, thalamic, pineal region, brainstem, and fourth ventricle) can be estimated up to 90% of cases. We believe that the mamillopontine distance (MPD) - the distance between the lower surface of the mammillary body and the upper surface of the pons in the sagittal images - can be a sufficiently reliable alternative to the Evans' index (EI) for the diagnosis of ObH. PATIENTS AND METHODS: The results of mamillopontine distance (MPD), Evans' index (EI), and angle of corpus callosum (ACC) measurement of 43 patients with non-communicative hydrocephalus were analyzed compared with results of 30 people without brain pathology. RESULTS: Findings revealed that MPD is a strong and reliable alternative to the EI. MPD showed high specificity and sensitivity in the diagnosis of occlusive hydrocephalus. Moreover, from those findings, we have proposed classification of the degree of hydrocephalus severity, depending on the MPD. CONCLUSION: MPD one of the more accurate and powerful method for defining presence of hydrocephalus in-patient even in early stage of occlusion. It has high specificity and sensitivity and capable classify hydrocephalus into grades according to severity.

Computational Fluid Dynamics Analysis and Correlation with Intraoperative Aneurysm Features.

INTRODUCTION: There are many controversies about computational fluid dynamics (CFD) findings and aneurysm initiation, growth, and ultimate rupture. The aim of our work was to analyze CFD data in a consecutive series of patients and to correlate them with intraoperative visual aneurysm findings. METHODS: Hemoscope software (Amin, Ziosoft Corporation, Minato ward, Tokyo, Japan) was used to process images from 17 patients who underwent clipping of 18 aneurysms. Pressure (P), wall shear stress (WSS) gradient and vectors, normalized WSS, and streamlines (SL) direction and velocity were assessed. CFD data were compared to intraoperative visual findings. A total of 39 aneurysm wall areas were assessed. RESULTS: Red, thin aneurysm wall areas were more often associated with low WSS. However, the association of low WSS with high P, diverging WSS vectors, direct impact of SL, and high SL velocity more frequently matched with yellow, atherosclerotic aneurysm walls. CONCLUSIONS: Low WSS alone is not sufficient to determine the thickness of an aneurysm wall. Its association with other parameters might enable one to distinguish preoperatively atherosclerotic, thick areas (high P, diverging WSS vectors, high flow velocity) from thin areas with higher rupture risk (parallel WSS vectors, lower flow velocity). The changing balance between these parameters can modify the features and the risk of rupture of aneurysm wall over time.