Reliability of High-resolution Gadolinium-enhanced MR Cisternography and Gasket-seal Technique for Management of Anterior Skull Base Defects.

PURPOSE: Precise preoperative localization of anterior skull base defects is important to plan surgical access, increase the success rate and reduce complications. A stable closure of the defect is vital to prevent recurrence of cerebrospinal fluid (CSF) rhinorrhea. The purpose of this retrospective case series was to evaluate the reliability of a new high-resolution gadolinium-enhanced compressed-sensing SPACE technique (CS T1 SPACE) for magnetic resonance (MR) cisternography to detect cerebrospinal fluid leaks of the anterior skull base and to assess the long-term success rate of the gasket-seal technique for closure of skull base defects. METHOD: All patients with spontaneous or postoperative cerebrospinal fluid rhinorrhea and defects of the anterior skull base presenting to the Departments of Otorhinolaryngology and Neurosurgery between 2019 and 2020, receiving a computed tomography (CT) cisternography and MR cisternography (on a 3T whole-body MR scanner using a 64-channel head and neck coil) with CS T1 SPACE sequence and closure of the defect with the gasket-seal technique, were enrolled in the study. For the cisternography, iodinated contrast agent (15 ml Solutrast 250 M®), saline (4 mL) mixed with a 0.5 mL of gadoteridol was injected into the lumbar subarachnoid space. RESULTS: A total of four patients were included in the study and MR cisternography with CS T1 SPACE sequence was able to precisely localize CSF leaks in all patients. The imaging results correlated with intraoperative findings. All defects could be successfully closed with the gasket-seal technique. The mean follow-up was 35.25 months (range 33-37 months). CONCLUSION: MR cisternography with CS T1 SPACE sequence could be a promising technique for precise localization of CSF leaks and the gasket-seal technique resulted in good closure of the CSF fistula in this case series.

SVM-Based Normal Pressure Hydrocephalus Detection.

BACKGROUND AND PURPOSE: As magnetic resonance imaging (MRI) signs of normal pressure hydrocephalus (NPH) may precede clinical symptoms we sought to evaluate an algorithm that automatically detects this pattern. METHODS: A support vector machine (SVM) was trained in 30 NPH patients treated with ventriculoperitoneal shunts and 30 healthy controls. For comparison, four neuroradiologists visually assessed sagittal MPRAGE images and graded them as no NPH pattern, possible NPH pattern, or definite NPH pattern. RESULTS: Human accuracy to visually detect a NPH was between 0.85 and 0.97. Interobserver agreement was substantial (κ = 0.656). Accuracy of the SVM algorithm was 0.93 and AUROC 0.99. Among 272 prespecified regions, gray matter and CSF volumes of both caudate, the right parietal operculum, the left basal forebrain, and the 4th ventricle showed the highest discriminative power to separate a NPH and a no NPH pattern. CONCLUSION: A NPH pattern can be reliably detected using a support vector machine (SVM). Its role in the work-up of asymptomatic patients or neurodegenerative disease has to be evaluated.

Cerebral Abscess Following Endovascular Treatment of Aneurysm: Report of 2 Cases and Review of the Literature.

INTRODUCTION: Endovascular treatment is growing in popularity globally as an important treatment option for intracranial aneurysms. Cerebral infection as a complication of endovascular treatment of aneurysms is sufficiently rare that only 6 isolated cerebral abscess cases have been reported thus far. CASE REPORT: In this report, we present 2 cerebral abscesses from 3 institutions, which developed after coil embolization of anterior communicating artery and middle cerebral artery aneurysms. CONCLUSION: This report was written to discuss the possible mechanisms underlying cerebral abscess after endovascular treatment of aneurysms and to suggest potential treatment and prevention methods.

Parenchymal density changes in acute pulmonary embolism: Can quantitative CT be a diagnostic tool? A preliminary study.

PURPOSE: Determine the ability of quantitative CT (QCT) in defining parenchymal density changes in acute pulmonary embolism (PE). MATERIAL & METHODS: Mean lung density (MLD) and percentage distribution values (PDV) were calculated in 34 patients suspected of PE using software application based on computerized volumetric anatomical segmentation. RESULTS: Total, left, and right MLD differed significantly between emboli positive(n=23) and negative(n=11) groups(p<0.006, p<0.009, p<0.014). PDVs differed between groups (p<0.05) except for LUZ and RLZ. When PE was present in lobe &/segment branches, PDVs were significantly lower except RUZ. CONCLUSION: QCT is a promising application for defining parenchymal density changes in PE revealing potential functional impact of emboli. This preliminary study suggests QCT could provide added value to CTPA in peripheral PE.