Citations

Spontaneous intracranial hypotension (SIH) is an uncommon headache etiology, typically attributable to an unprovoked occult spinal CSF leak. Although frequently benign, serious complications may occur, including cerebral venous thrombosis (CVT). The objective of this study was to examine a highly complicated case of CVT attributable to SIH as a lens for understanding the heterogeneous literature on this rare complication, and to provide useful, evidence-based, preliminary clinical recommendations. A 43-year-old man presented with 1 week of headache, dizziness, and nausea, which precipitously evolved to hemiplegia. CT venography confirmed CVT, and therapeutic heparin was initiated. He suffered a generalized seizure due to left parietal hemorrhage, which subsequently expanded. He developed signs of mass effect and herniation, heparin was discontinued, and he was taken to the operating room for clot evacuation and external ventricular drain placement. Intraoperatively, the dura was deflated, suggesting underlying SIH. Ventral T-1 CSF leak was identified, which failed multiple epidural blood patches and required primary repair. The patient ultimately made a complete recovery. Systematic review identified 29 publications describing 36 cases of SIH-associated CVT. Among 31 patients for whom long-term neurological outcome was reported, 25 (81%) recovered completely. Underlying coagulopathy/risk factors were identified in 11 patients (31%). CVT is a rare and potentially lethal sequela occurring in 2% of SIH cases. Awareness of the condition is poor, risking morbid complications. Evaluation and treatment should be directed toward identification and treatment of occult CSF leaks. Encouragingly, good neurological outcomes can be achieved through vigilant multidisciplinary neurosurgical and neurocritical care.

Abstract BACKGROUND Increased body mass index (BMI) may be protective against cerebral ischemia in certain clinical contexts. OBJECTIVE To investigate whether increased BMI was associated with delayed cerebral ischemia (DCI) and subsequent infarction after aneurysmal subarachnoid hemorrhage (aSAH). METHODS We retrospectively reviewed the clinical course of patients presenting to our institution for management of aSAH. Patient were segregated according to BMI< or ≥29.4, a value determined by Classification and Regression Tree analysis. Predictors of DCI and delayed infarction were identified using stepwise multivariate logistic regression analysis. RESULTS There were 161 patients included for analysis. Average BMI within our patient cohort was 28.9, with 67 patients presenting with a BMI of ≥29.4 on admission. DCI occurred in 50 patients (31.1%) and was complicated by delayed infarction in 15 patients (9.3%). On stepwise multivariate analysis, BMI ≥ 29.4 was independently associated with reduced likelihood of DCI (odds ratio [OR] 0.42, 95% confidence interval [CI] 0.18-0.92) and delayed infarction (OR 0.13, 95% CI 0.02-0.61; P = .008). Increasing maximum flow velocity on transcranial Doppler ultrasound was independently associated with increased odds of both DCI (Unit OR 1.19, 95% CI 1.09-1.30; P < .001) and delayed infarction (Unit OR 1.31, 95% CI 1.13-1.56; P < .001), while intracerebral hemorrhage was independently associated with increased odds of delayed infarction (OR 6.99, 95% CI 1.82-30.25; P = .005). CONCLUSION We report an association between elevated BMI and reduced incidence of DCI and delayed infarction, suggesting a protective effect of increasing BMI on the risk of ischemic complications after aSAH.

BackgroundCarotid plaque imaging with MRI is becoming more commonplace, but practical challenges exist in performing plaque imaging with surface coils.PurposeTo compare the diagnostic performance of a carotid plaque MRI protocol using a standard neurovascular coil (Neurovascular Coil Protocol) to a higher‐resolution carotid plaque MRI using carotid surface coils (Surface Coil Protocol) in characterizing carotid plaque.Study TypeProspective study comparing two MR techniques in plaque characterization.PopulationThirty‐eight consecutive carotid artery disease patients.Field Strength/SequencePatients underwent 3T MRI using 1) a Neurovascular Coil Protocol including the following sequences: 3D‐FSE T1 pre/postcontrast and precontrast 3D IR‐FSPGR, and 2) a Surface Coil Protocol using standard multicontrast MRI sequences.AssessmentPlaque characteristics analyzed by two independent neuroradiologists included intraplaque hemorrhage (IPH), lipid‐rich necrotic‐core (LRNC), and thin/ruptured fibrous cap (TRFC).Statistical TestsDiagnostic performance of the Neurovascular Coil Protocol was compared to the Surface Coil Protocol reference standard using receiver‐operating curves.ResultsFor IPH, sensitivity, specificity, and area under the curve (AUC) of the Neurovascular Coil Protocol were 91.1% (95% confidence interval [CI] = 78.8–97.5%), 87.0% (95% CI = 66.4–97.2%), and 0.92, respectively. For LRNC without IPH sensitivity, specificity, and AUC were 73.3% (95% CI = 44.9–92.2%), 85.7% (95% CI = 67.3–96.0%), and 0.84, respectively. For TRFC, sensitivity, specificity, and AUC were 35.3% (95% CI = 14.2–61.7%), 97.6% (95% CI = 87.4–99.9%), and 0.66 respectively. Interobserver agreement for IPH, LRNC, and TRFC using the Neurovascular Coil Protocol were k = 0.87 (95% CI = 0.75–0.99), k = 0.54 (95% CI = 0.29–0.80), and k = 0.41 (95% CI = 0.08–0.74), respectively.Data ConclusionOur Neurovascular Coil Protocol has high sensitivity, specificity, and accuracy in identifying IPH and LRNC but is limited in assessment of TRFC.Level of Evidence: 1Technical Efficacy: Stage 2J. Magn. Reson. Imaging 2018;47:1264–1272.

Background and Purpose— Superficial siderosis (SS) is characterized by hemosiderin deposition in the superficial layers of the central nervous system and can be seen during postmortem examination or with iron-sensitive magnetic resonance imaging techniques. The distribution of SS may predict the probable underlying cause. This study aimed to report the prevalence and natural history of SS in a population-based study. Methods— Brain magnetic resonance imaging scans from the MCSA (Mayo Clinic Study of Aging), a population-based study of residents 50 to 89 years of age in Olmsted County, Minnesota, were reviewed. Participants with imaging consistent with SS were identified from 2011 through 2016. An inverse probability weighting approach was used to convert our observed frequencies to population prevalence of SS. Additional data abstracted included amyloid positron emission tomography, Apolipoprotein E genotype, coexisting cerebral microbleeds, and extent of SS. Results— A total of 1412 participants had eligible magnetic resonance imaging scans. Two participants had infratentorial SS, restricted to the posterior fossa. Thirteen participants had cortical SS involving the cerebral convexities (7 focal and 6 disseminated). Only 3 of the participants with cortical SS (23%) also had cerebral microbleeds. The population prevalence of SS was 0.21% (95% confidence interval, 0–0.45) in those 50 to 69 years old and 1.43% (confidence interval, 0.53–2.34) in those over 69 years old. Apolipoprotein E ε2 allele was more common in those with SS (57.1% versus 15.0%; P <0.001). Compared with participants without SS, those with SS were also more likely to have a positive amyloid positron emission tomographic scan (76.9% versus 29.8%; P <0.001). Conclusions— SS may be encountered in the general elderly population. The association with increased amyloid burden and Apolipoprotein E ε2 genotype supports cerebral amyloid angiopathy as the most common mechanism. Longitudinal follow-up is needed to evaluate the risk of subsequent hemorrhage in cases of incidentally discovered SS.