Prognostic value of a qualitative brain MRI scoring system after cardiac arrest.

BACKGROUND AND PURPOSE: To develop a qualitative brain magnetic resonance imaging (MRI) scoring system for comatose cardiac arrest patients that can be used in clinical practice. METHODS: Consecutive comatose postcardiac arrest patients were prospectively enrolled. Routine MR brain sequences were scored by two independent blinded experts. Predefined brain regions were qualitatively scored on the fluid-attenuated inversion recovery (FLAIR) and diffusion-weighted imaging (DWI) sequences according to the severity of the abnormality on a scale from 0 to 4. The mean score of the raters was used. Poor outcome was defined as death or vegetative state at 6 months. RESULTS: Sixty-eight patients with 88 brain MRI scans were included. Median time from the arrest to the initial MRI was 77 hours (IQR 58-144 hours). At 100% specificity, the "cortex score" performed best in predicting unfavorable outcome with a sensitivity of 55%-60% (95% CI 41-74) depending on time window selection. When comparing the "cortex score" with historically used predictors for poor outcome, MRI improved the sensitivity for poor outcome over conventional predictors by 27% at 100% specificity. CONCLUSIONS: A qualitative MRI scoring system helps assess hypoxic-ischemic brain injury severity following cardiac arrest and may provide useful prognostic information in comatose cardiac arrest patients.

Cerebral venous thrombosis: a potential mimic of primary traumatic brain injury in infants.

OBJECTIVE: Hyperdense venous thrombi on unenhanced head CT may be misinterpreted as different types of extraaxial hemorrhages, and hemorrhagic venous infarctions may be interpreted as parenchymal contusion, leading to an incorrect diagnosis of trauma as the cause of the blood products. The purpose of this article is to show the various appearances of cerebral venous thrombosis (CVT) that mimic different types of hemorrhages and to show hemorrhagic venous infarctions that mimic parenchymal contusions. CONCLUSION: CVT, as an entity, must be kept in the differential diagnosis when patients present with extraaxial hyperdensities on unenhanced head CT so appropriate management can be initiated to minimize potentially devastating consequences.

Exertional reversible cerebral vasoconstriction responsive to verapamil.

We present a case of a 25-year-old male with severe headaches associated with exertion and sexual intercourse with vasoconstriction on magnetic resonance and CT angiograms done during his typical headaches. The headache syndrome and angiographic findings resolved after starting low-dose verapamil. Perhaps, some cases of primary exertional and primary headaches associated with sexual activity are associated with reversible cerebral vasoconstriction responsive to calcium channel blockers.

Performance of PROPELLER relative to standard FSE T2-weighted imaging in pediatric brain MRI.

BACKGROUND: T2-weighted fast spin-echo imaging (T2-W FSE) is frequently degraded by motion in pediatric patients. MR imaging with periodically rotated overlapping parallel lines with enhanced reconstruction (PROPELLER) employs alternate sampling of k-space to achieve motion reduction. OBJECTIVE: To compare T2-W PROPELLER FSE (T2-W PROP) with conventional T2-W FSE for: (1) image quality; (2) presence of artefacts; and (3) ability to detect lesions. MATERIALS AND METHODS: Ninety-five pediatric patients undergoing brain MRI (1.5 T) were evaluated with T2-W FSE and T2-W PROP. Three independent radiologists rated T2-W FSE and T2-W PROP, assessing image quality, presence of artefacts, and diagnostic confidence. Chi-square analysis and Wilcoxon signed rank test were used to assess the radiologists' responses. RESULTS: Compared with T2-W FSE, T2-W PROP demonstrated better image quality and reduced motion artefacts, with the greatest benefit in children younger than 6 months. Although detection rates were comparable for the two sequences, blood products were more conspicuous on T2-W FSE. Diagnostic confidence was higher using T2-W PROP in children younger than 6 months. Average inter-rater agreement was 87%. CONCLUSION: T2-W PROP showed reduced motion artefacts and improved diagnostic confidence in children younger than 6 months. Thus, use of T2-W PROP rather than T2-W FSE should be considered in routine imaging of this age group, with caution required in identifying blood products.

Traumatic spinal cord injury: accidental versus nonaccidental injury.

A 21-month-old boy with steroid-dependent asthma presented to the emergency room with Glascow Coma Score (GCS) 3 and retinal hemorrhages. He was found to have subdural and subarachnoid hemorrhage on computed tomography plus findings of hypoxic-ischemic encephalopathy (HIE). The caretaker history was thought to be inconsistent with the clinical and imaging features, and the patient was diagnosed with nonaccidental injury (NAI) and "shaken baby syndrome." The autopsy revealed a cranial impact site and fatal injury to the cervicomedullary junction. Biomechanical analysis provided further objective support that, although NAI could not be ruled out, the injuries could result from an accidental fall as consistently described by the caretaker.

Cutting-edge imaging of the spine.

Damage to the spinal cord may be caused by a wide range of pathologies and generally results in profound functional disability. A reliable diagnostic workup of the spine is very important because even relatively small lesions in this part of the central nervous system can have a profound clinical impact. MR imaging has become the method of choice for the detection and diagnosis of many spine disorders. Various innovative MR imaging methods have been developed to improve neuroimaging, including better pulse sequences and new MR contrast parameters. These new "cutting-edge" technologies have the potential to impact profoundly the ease and confidence of spinal disease interpretation and offer a more efficient diagnostic workup of patients suffering from spinal disease.