Journal of neuroimaging : official journal of the American Society of Neuroimaging
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Despite multimodal treatment of glioblastoma (GBM), recurrence beyond the initial tumor volume is inevitable. Moreover, conventional MRI has shortcomings that hinder the early detection of occult white matter tract infiltration by tumor, but diffusion tensor imaging (DTI) is a sensitive probe for assessing microstructural changes, facilitating the identification of progression before standard imaging. This sensitivity makes DTI a valuable tool for predicting recurrence. A systematic review was therefore conducted to investigate how DTI, in comparison to conventional MRI, can be used for predicting GBM progression. ⋯ These findings suggest that DTI metrics may be useful for guiding surgical and radiotherapy planning for GBM patients, and for informing long-term surveillance. Understanding the current state of the literature pertaining to these metrics' trends is crucial, particularly as DTI is increasingly used as a treatment-guiding imaging modality.
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Ancillary testing is essential for diagnosing brain death/death by neurologic criteria (BD/DNC) when clinical determination (neurologic exam and apnea testing) cannot be fully or safely performed. Transcranial Doppler ultrasound (TCD) has been recommended as an ancillary test; however, the technical descriptions have been heterogeneous. We aimed to consolidate the technical considerations related to the use of TCD as an ancillary test in the evaluation of BD/DNC. ⋯ We found significant inconsistencies and a lack of technical details described in the literature. Next steps include a national survey of current TCD protocols for BD/DNC evaluation, and an expert consensus guidelines report on the technical use of TCD as an ancillary test.
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Intracranial pressure (ICP) monitoring is a cornerstone of neurocritical care in managing severe brain injury. However, current invasive ICP monitoring methods carry significant risks, including infection and intracranial hemorrhage, and are contraindicated in certain clinical situations. Additionally, these methods are not universally available. ⋯ Automating both ONSD image acquisition and measurement could enhance accuracy and reliability, thereby improving its utility as a noninvasive ICP estimation tool. A range of image analysis and machine learning (ML) techniques have been applied to address these challenges. In this paper, we provide a narrative review of the current literature on ONSD automation, examining the strengths and limitations of classical image analysis and ML models in improving ONSD-based ICP assessment.
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The central vein sign (CVS) is a diagnostic imaging biomarker for multiple sclerosis (MS). FLAIR* is a combined MRI contrast that provides high conspicuity for CVS at 3 Tesla (3T), enabling its sensitive and accurate detection in clinical settings. This study evaluated whether CVS conspicuity of 3T FLAIR* is reliable across imaging sites and MRI vendors and whether gadolinium (Gd) contrast increases CVS conspicuity. ⋯ CVS conspicuity on 3T FLAIR* is consistent across imaging sites and MRI vendors. Moreover, Gd-based contrast agent significantly improved CVS conspicuity on 3T FLAIR*. These findings support the implementation of FLAIR* in clinical settings for MS.
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The venous outflow profile (VOP) is a crucial yet often overlooked aspect affecting stroke outcomes. It plays a major role in the physiopathology of acute cerebral ischemia, as it accounts for both the upstream arterial collaterals and cerebral microperfusion. This enables it to circumvent the limitations of various arterial collateral evaluation systems, which often fail to consider impaired autoregulation and its impact on cerebral blood flow at the microcirculatory levels. In this narrative review, we will highlight the different parameters and modalities used to assess the VOP in acute ischemia. ⋯ VOP parameters' significance lies in their potential to predict tissue fate and, subsequently, clinical outcomes. Recent studies indicate that favorable VOP is independently associated with slower rates of infarct edema progression, smaller infarct volumes, and higher rates of functional independence after 90 days. Moreover, it is considered a predictor of recanalization success and the first-pass effect during mechanical thrombectomy. Conversely, an unfavorable VOP predicts futile recanalization and indicates a higher risk of reperfusion hemorrhage. Our aim is to explore these prognostic implications and their relevance in determining the utility of intracranial intervention.