Rapid T 2 ∗ -weighted MRI using multishot EPI with retrospective motion and phase correction in the emergency department.

PURPOSE: Brain MRI is increasingly used in the emergency department (ED), where T 2 * $$ {\mathrm{T}}_2^{\ast } $$ -weighted MRI is an essential tool for detecting hemorrhage and stroke. The goal of this study was to develop a rapid T 2 * $$ {\mathrm{T}}_2^{\ast } $$ -weighted MRI technique capable of correcting motion-induced artifacts, thereby simultaneously improving scan time and motion robustness for ED applications. METHODS: A 2D gradient-echo (GRE)-based multishot EPI (msEPI) technique was implemented using a navigator echo for estimating motion-induced errors. Bulk rigid head motion and phase errors were retrospectively corrected using an iterative conjugate gradient approach in the reconstruction pipeline. Three volunteers and select patients were imaged at 3 T and/or 1.5 T with an approximately 1-min full-brain protocol using the proposed msEPI technique and compared to an approximately 3-min standard-of-care GRE protocol to examine its performance. RESULTS: Data from volunteers demonstrated that in-plane motion artifacts could be effectively corrected with the proposed msEPI technique, and through-plane motion artifacts could be mitigated. Patient images were qualitatively reviewed by one radiologist without a formal statistical analysis. These results suggested the proposed technique could correct motion-induced artifacts in the clinical setting. In addition, the conspicuity of susceptibility-related lesions using the proposed msEPI technique was comparable, or improved, compared to GRE. CONCLUSION: A 1-min full-brain T 2 * $$ {\mathrm{T}}_2^{\ast } $$ -weighted MRI technique was developed using msEPI with a navigator echo to correct motion-induced errors. Preliminary clinical results suggest faster scans and improved motion robustness and lesion conspicuity make msEPI a competitive alternative to traditional T 2 * $$ {\mathrm{T}}_2^{\ast } $$ -weighted MRI techniques for brain studies in the ED.

Moyamoya Disease in an 18-Month-Old Female Caucasian Complicated by Cerebral Hyperperfusion Syndrome Following Indirect Revascularization.

BACKGROUND Cerebral hyperperfusion syndrome is a rare complication of indirect revascularization due to moyamoya disease, but has not been reported previously in the pediatric population. We present a case of an 18-month-old girl with moyamoya disease that was treated with bilateral pial synangiosis and had complications consistent with cerebral hyperperfusion syndrome. This case report discusses the pathophysiological mechanisms involved in cerebral hyperperfusion in moyamoya syndrome. CASE REPORT An 18-month-old female Caucasian presented with seizures and weakness of the left side. Angiography confirmed bilateral cerebral moyamoya disease that was worse on the right side. Indirect revascularization with pial synangiosis was first performed on the right side to allow for healing. Five months later, pial synangiosis was then performed on the left side. Postoperatively, the patient experienced increased intracranial pressure (ICP), suggesting cerebral hyperperfusion syndrome. She was treated with a repeat lumbar puncture, a lumbar drain, and a lumbar shunt. CONCLUSIONS This report demonstrates a case of cerebral hyperperfusion syndrome as a complication of moyamoya disease in a pediatric patient. Although the patient progressed well after placement of a lumbar shunt, this case demonstrates the occurrence of cerebral hyperperfusion syndrome as a complication of revascularization in pediatric patients and highlights the need for further research in this area.