Blood flow insufficiency in both the LSA and MCA cortical branches that perfuse the corticospinal tract can be detected by intraoperative MEP monitoring. Somatosensory evoked potential monitoring is not reliable enough to detect BFI in the MCA branches and the LSAs.

An 8-year-old boy presented with a rare cerebral medulloepithelioma manifesting as headache, nausea, and vomiting. Neuroimaging demonstrated a mass containing a cyst in the left frontal lobe. Gross total resection of the tumor with a 1-cm margin was performed under intraoperative monitoring. The histological diagnosis was medulloepithelioma. Stereotactic radiotherapy (total dose 20 Gy) was given to the brain up to 1 cm from the surgical margin. Follow-up neuroimaging 5 years later showed no signs of recurrence. He now attends junior high school, with normal mental and physiological development. Medulloepitheliomas are rare, highly malignant embryonal tumors of the central nervous system. Combined gross total tumor resection and radiotherapy are recommended to obtain the most favorable outcome.

Background Silent scan magnetic resonance angiography (silent-MRA) as an arterial spin labeling technique offering sound reduction is insensitive to saturation effect. Time-of-flight (TOF)-MRA has limitations in terms of fine or slow-flow blood vessels due to sensitive saturation effects. Purpose Silent-MRA was compared with TOF-MRA for visualizing cerebral arteries in patients with Moyamoya disease (MMD). Material and Methods Forty-one patients with MMD were scanned with both silent-MRA and TOF-MRA. Silent-MRA was compared with TOF-MRA both quantitatively and qualitatively. Quantitatively, both signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) were measured. Qualitatively, steno-occlusive severity of the main cerebral arteries and grading of Moyamoya vessels (MMVs) were evaluated. The grading for MMVs was classified into one of five categories (1 = absolutely negative; 5 = absolutely positive). Results Both SNR and CNR were significantly higher in TOF-MRA (SNR = 155.2 ± 90.8; CNR = 116.6 ± 72.0) than in silent-MRA (SNR = 45.8 ± 10.1; CNR = 38.6 ± 10.1) (P < 0.001). No significant difference in steno-occlusive severity of the main cerebral arteries in either right or left cerebral hemispheres was observed between silent-MRA and TOF-MRA. In grading MMVs, the silent-MRA score (mean ± SD = 4.6 ± 0.5) was significantly higher than that of TOF-MRA (3.2 ± 1.6) (P < 0.001). Conclusion Silent-MRA appears to better visualize MMVs than TOF-MRA and it can equally depict steno-occlusive lesions of the cerebral arteries.

BACKGROUND AND PURPOSE: Recanalization after coil embolization is widely studied. However, there are limited data on how recanalized aneurysms rupture. Herein, we describe our experience with the rupture of recanalized aneurysms and discuss the type of recanalized aneurysms at greatest rupture risk. MATERIALS AND METHODS:A total of 426 unruptured aneurysms and 169 ruptured aneurysms underwent coil embolization in our institution between January 2009 and December 2017. Recanalization occurred in 38 (8.9%) of 426 unruptured aneurysms (unruptured group) and 37 (21.9%) of 169 ruptured aneurysms (ruptured group). The Modified Raymond-Roy classification on DSA was used to categorize the recanalization type. Follow-up DSA was scheduled until 6 months after treatment, and follow-up MRA was scheduled yearly. If recanalization was suspected on MRA, DSA was performed. RESULTS:In the unruptured group, the median follow-up term was 74.0 months. Retreatment for recanalization was performed in 18 aneurysms. Four of 20 untreated recanalized aneurysms (0.94% of total coiled aneurysms) ruptured. In untreated recanalized aneurysms, class IIIb aneurysms ruptured significantly more frequently than class II and IIIa (P ¼ .025). In the ruptured group, the median follow-up term was 28.0 months. Retreatment for recanalization was performed in 16 aneurysms. Four of 21 untreated recanalized aneurysms (2.37% of total coiled aneurysms) ruptured. Class IIIb aneurysms ruptured significantly more frequently than class II and IIIa (P ¼ .02). CONCLUSIONS:The types of recanalization after coil embolization may be predictors of rupture. Coiled aneurysms with class IIIb recanalization should undergo early retreatment because of an increased rupture risk. ABBREVIATIONS: AcomA ¼ anterior communicating artery; PcomA ¼ posterior communicating artery E ndovascular coiling of cerebral aneurysms is widely performed, with continued improvement in related techniques and devices. 1,2 However, an important problem with endovascular coiling is recanalization after coil embolization. Coiled aneurysms that show major recanalization require additional coiling to prevent rupture. The incidence of recanalization after coiling ranges from 6.1% to 33.6%, 3,4 and the reported risk factors for recanalization include aneurysm morphologic features, coil compaction and/or migration, and various endovascular embolization techniques. [3][4][5] Although recanalization after coil embolization has been previously evaluated, there are insufficient data on the way in which recanalized aneurysms rupture. Thus, in the present study, we describe our experience with the rupture of aneurysms that have recanalized after coil embolization in Kobe City Medical Center General Hospital and discuss the type of recanalized aneurysms at greatest risk of rupture and the appropriate timing of followup angiography and retreatment. MATERIALS AND METHODS Patient and Aneurysm CharacteristicsBetween January 2009 and December 2017, coil embolization was performed in a total of 426 unruptured aneurysm...

Objective Silent magnetic resonance angiography (MRA) was compared with time-of-flight (TOF)–MRA in imaging of arteriovenous malformations (AVMs) of the brain. Methods Thirty-five consecutive patients with AVMs of the brain were included. Quantitative analyses were performed by measuring both signal-to-noise ratio and contrast-to-noise ratio of the nidus. Qualitative analysis (scores 1–4) was performed by evaluating depictions of feeding arteries and draining veins independently by 2 reviewers. Results Both signal-to-noise ratio and contrast-to-noise ratio in TOF-MRA were significantly higher than those in silent MRA. For both feeders and drainers, scores were significantly higher in silent MRA than in TOF-MRA for both reviewers. Interrater agreement was higher in silent MRA than in TOF-MRA. Conclusions Silent MRA visualized feeders and drainers in AVMs significantly better than did TOF-MRA. Interrater agreement was also better in silent MRA.