Object. The diagnosis of low-grade glioma (LGG) cannot be based exclusively on conventional magnetic resonance (MR) imaging studies, and target selection for stereotactic biopsy is a crucial issue given the high risk of sampling errors. The authors hypothesized that perfusion-weighted imaging could provide information on the microcirculation in presumed supratentorial LGGs. Methods. All adult patients with suspected (nonenhancing) supratentorial LGGs on conventional MR imaging between February 2001 and February 2004 were included in this study. Preoperative MR imaging was performed using a dynamic first-pass gadopentate dimeglumine—enhanced spin echo—echo planar perfusion-weighted sequence, and the tumors' relative cerebral blood volume (rCBV) measurements were expressed in relation to the values observed in contralateral white matter. In patients with heterogeneous tumors a stereotactic biopsy was performed in the higher perfusion areas before resection. Among 21 patients (16 men and five women with a mean age of 36 years, range 23–60 years), 10 had diffuse astrocytomas (World Health Organization Grade II) and 11 had other LGGs and anaplastic gliomas. On perfusion-weighted images demonstrating heterogeneous tumors, areas of higher rCBV focus were found to be oligodendrogliomas or anaplastic astrocytomas on stereotactic biopsy; during tumor resection, however, specimens were characterized predominantly as astrocytomas. Diffuse astrocytomas were associated with significantly lower mean rCBV values compared with those in the other two lesion groups (p < 0.01). The rCBV ratio cutoff value that permitted better discrimination between diffuse astrocytomas and the other lesion groups was 1.2 (80% sensitivity and 100% specificity). Conclusions. Perfusion-weighted imaging is a feasible method of reducing the sampling error in the histopathological diagnosis of a presumed LGG, particularly by improving the selection of targets for stereotactic biopsy.

Traumatic brain injury (TBI) is the main cause of death in trauma victims and causes high rates of disability and neurological sequelae. Approximately 38-65% of traumatic brain contusions (TBC) demonstrate hemorrhagic expansion on serial computed tomography (CT) scans. However, thus far, no single variable can accurately predict the hemorrhage expansion of a TBC. Our purpose was to evaluate contrast extravasation (CE) as a predictor of expansion, mortality and poor outcome in TBC in a Brazilian cohort. After institutional review board approval, we used multidetector computed tomography angiography (MDCTA) to study 121 consecutive patients (106 men, 87.6%) with ages varying from 10 to 85 years. Informed consent was obtained from all subjects. The clinical and imaging findings were correlated with the findings on the initial MDCTA using either Fisher’s exact test or Student’s t-test and a multivariate logistic regression model. Of the individuals who presented CE in TBC, 21.8% died (in-hospital mortality), whereas in the absence of this sign, the mortality rate was 7.6% (p = 0.014). Additionally, expansion of the hemorrhagic component of the TBC was detected in 61.1% of the CE-positive patients, whereas expansion was only observed in 10% of the CE-negative patients (p < 0.001). Poor outcome was observed in 24.2% of the patients in the CE-negative group, but in the presence of CE, 72.7% evolved with poor outcome (p < 0.001). The CE was a strong independent predictor of expansion, poor outcome, and increased risk of in-hospital mortality in our series of patients with TBC.

The majority of coronavirus disease 2019 (COVID-19) have been confirmed in adults, with only a few reported cases in children. In the pediatric population, COVID-19 infection appears to be often unremarkable or associated with mild respiratory symptoms. Little is known about neurologic complications related to COVID-19 in newborns. We present a case of severe encephalitis with cytotoxic brain edema in a newborn with COVID-19.

BACKGROUND AND PURPOSE: Intracranial pressure modifications caused by a skull defect, such as craniectomy or craniotomy, may change the hemodynamics and decrease the accuracy of CTA to confirm brain death. This study aimed to evaluate the impact of a skull defect and the interpretation criteria of images on this diagnostic test. MATERIALS AND METHODS: A series of consecutive patients with a clinical diagnosis of brain death underwent CTA (case group), while the control group comprised patients with acute ischemic stroke in the same period. CTA criteria adopted to confirm brain death were the absence of opacification of the M4 branches and internal cerebral veins. The evaluation also included the presence of “stasis filling.” Cases were stratified as intact skull, craniotomy, and craniectomy. Three neuroradiologists evaluated all examinations independently. RESULTS: In the case group, according to the Frampas criteria, the sensitivity of CTA to confirm brain death was 95.5% in patients with intact skull, 87.5% with craniotomy, and 60% with craniectomy. False-negative diagnoses of brain death were 15.6%, related to stasis filling in 71.4% (P < .001). However, according to the “modified Frampas criteria,” the sensitivity of CTA to confirm brain death was 100% in patients with intact skull, 93.8% with craniotomy, and 80% with craniectomy. False-negative diagnoses of brain death were found in 6.2% of patients, and there was no stasis filling. CTA showed 100% specificity in the control group. There were no disagreements among observers. CONCLUSIONS: CTA had a high diagnostic accuracy and reproducibility to confirm brain death in patients with an intact skull. The modified Frampas criteria increased the sensitivity of CTA, particularly in patients with a skull defect. A concurrent skull defect, especially craniectomy, can decrease the sensitivity of CTA to confirm brain death.