- Safety and Efficacy of Transvenous Embolization of Ruptured Brain Arteriovenous Malformations as a Last Resort: A Prospective Single-Arm Study
Twenty-one consecutive patients with ruptured brain AVMs who underwent transvenous embolization were prospectively followed between November 2016 and November 2018. Complete AVM nidus obliteration was shown in 16 (84%) of 19 patients. One (5%) patient with a small residual nidus after treatment showed complete obliteration at 13-month follow-up. There were 5 hemorrhages and 1 infarction; 4 patients' symptoms improved gradually. Transvenous embolization can be performed only in highly selected hemorrhagic brain AVMs with high complete obliteration rates, but it should not be considered as a first-line treatment.
- Automatic Spinal Cord Gray Matter Quantification: A Novel Approach
The authors assessed the reproducibility and accuracy of cervical spinal cord gray matter and white matter cross-sectional area measurements using magnetization inversion recovery acquisition images and a fully automatic postprocessing segmentation algorithm. The cervical spinal cord of 24 healthy subjects was scanned in a test-retest fashion on a 3T MR imaging system. Twelve axial averaged magnetization inversion recovery acquisition slices were acquired over a 48-mm cord segment. GM and WM were both manually segmented by 2 experienced readers and compared with an automatic variational segmentation algorithm with a shape prior modified for 3D data with a slice similarity prior. Reproducibility was high for both methods, while being better for the automatic approach. The accuracy of the automatic method compared with the manual reference standard was excellent. They conclude that the fully automated postprocessing segmentation algorithm demonstrated an accurate and reproducible spinal cord GM and WM segmentation.
- Comparative Analysis of Volumetric High-Resolution Heavily T2-Weighted MRI and Time-Resolved Contrast-Enhanced MRA in the Evaluation of Spinal Vascular Malformations
The authors compared the efficacy of volumetric high-resolution heavily T2-weighted and time-resolved contrast-enhanced images in spinal vascular malformation diagnosis and feeder characterization and assessed whether a combined evaluation improved the overall accuracy of diagnosis in 28 patients. Both sequences demonstrated 100% sensitivity and 93.5% accuracy for the detection of spinal vascular malformations. Volumetric high-resolution heavily T2-weighted imaging was superior to time-resolved contrast-enhanced MR imaging for identification of spinal cord arteriovenous malformations while the opposite was observed for perimedullary arteriovenous fistulas. Both sequences showed equal sensitivity (100%) and accuracy (87%) for spinal dural arteriovenous fistulas. They conclude that combined volumetric high-resolution heavily T2-weighted imaging and time-resolved contrast-enhanced MR imaging can improve the sensitivity and accuracy of spinal vascular malformation diagnosis, classification, and feeder characterization.