Aggressive resection of insular tumors is possible using a meticulous surgical approach based on the regional insular anatomy, with high rates of gross-total resection and low rates of permanent neurological deficits. However, the risk of postoperative morbidities remains high, often caused by disruption of the vascular supply to the surrounding eloquent structures, especially the lenticulostriate arteries (LSAs) that supply the internal capsule. Three-dimensional 3-T time-of-flight (TOF) MR imaging was performed pre- and postoperatively in patients with insuloopercular gliomas. This 3D 3-T TOF MR imaging clearly visualized the LSAs and the relationships with the tumor margins. These findings were confirmed intraoperatively. Three-dimensional 3-T TOF MR imaging of the LSAs in patients with insuloopercular gliomas can help to maximize the extent of resection without neurological complications, preserve the LSAs during surgery, and assist in patient selection.

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Previous bleeding from a cerebral aneurysm indicates a higher risk of rupture. Hemosiderin may be detected during aneurysm surgery or by preoperative imaging sensitive to hemosiderin. The detection of hemosiderin deposits by T 2 * -weighted magnetic resonance (MR) imaging was evaluated in 49 patients with unruptured cerebral aneurysms who underwent open surgery. MR imaging was performed using 3.0 tesla MR scanner. Two sequences of T 2 *-weighted imaging, and proton density images were obtained. Preliminary study in patients with old subarachnoid hemorrhage provided the definitions of likely pathological findings during surgery and on T 2 * -weighted imaging due to previous hemorrhage. Hemosiderin deposits in the subarachnoid space were observed during surgery in 9 of the 49 patients, although no obvious rupture site was detected around the aneurysm wall. Size, presence of bleb, location, and number of aneurysms showed no significant difference between patients with and without hemosiderin deposition. Hypointense areas on T 2 *-weighted imaging were recognized in four patients. The mean size of the aneurysms in these patients was 9.8 mm, significantly larger than those in other patients (p ＝ 0.029). Hemosiderin deposits were observed during surgery in sites close to the lesions on T 2 *-weighted imaging in two of these four patients. Hemosiderin deposits are not rare in patients with unruptured aneurysms, and preoperative T 2 *-weighted imaging can detect such deposits.

Background: Timing of the onset of subarachnoid hemorrhage (SAH) is important for treatment decision-making, especially as some patients visit hospital several weeks after the onset of SAH. T2*-weighted (T2*W) magnetic resonance (MR) imaging is regarded as a sensitive method for the detection of deoxyhemoglobin or hemosiderin deposits. This study investigated the characteristics of the abnormal low intensity changes on T2*W imaging in patients with SAH, how long the abnormal low intensity persisted, and whether the day of onset could be predicted based on the T2*W imaging changes. Methods: The study included patients treated for SAH associated with ruptured cerebral aneurysms, or who had previously suffered such SAH and were followed up at our hospital, between 2006 and 2007. MR imaging was performed using a whole-body 3.0-tesla MR scanner. All patients underwent gradient recalled echo (GRE) and echo planar (EP) T2*W imaging. The strength of the low intensity areas was evaluated as the following 5 grades: grade 0, no abnormal low intensity on both GRE and EP T2*W images; grade 1, no abnormal intensity on GRE T2*W images and low intensity on EP T2*W images; grade 2, spotty abnormal low intensity on both GRE and EP T2*W images; grade 3, medium abnormal low intensity (<5 mm) on both GRE and EP T2*W images, and grade 4, large abnormal low intensity (≥5 mm) on both GRE and EP T2*W images. Results: A total of 50 patients with 74 MR images were included during the study period. Abnormal low intensity on T2*W imaging was observed in all patients. The T2* score gradually decreased from the onset of SAH until day 90, showing a significant negative linear correlation (R² = 0.25, p = 0.0002). On the other hand, the T2* score did not change after 1 year. The square correlation coefficient between the recorded and calculated days from the onset of SAH was 0.29 (p = 0.0107). The pure error was ±10 days. Conclusion: The T2* score gradually decreased until 90 days from the onset of SAH, but persisted for 16 years after the onset. We could predict the day of onset with pure error ±10 days in patients with SAH within 90 days of onset using our grading system for T2*W images.

To treat a type A SEDAVF, either TVE or microsurgical intradural drainer occlusion can be used for satisfactory long-term results with minimal surgical risks. For a case with multiple intradural draining veins, detachment of the venous lake should be considered.

A 26-year-old man presented with a case of angiocentric glioma manifesting as medically refractory epilepsy. Magnetic resonance imaging revealed a hyperintense lesion in the right superior frontal gyrus on T 2 -weighted imaging, with cortical hyperintense rim on T 1 -weighted images and minimum contrast enhancement. Video-electroencephalography (EEG) monitoring characterized his seizures as originating from the right frontal lobe. Long-term EEG recording from implanted subdural electrodes disclosed epileptic activities extending beyond the margin of the radiological lesion. Extended cortical resection of the superior frontal gyrus including the tumor and the surrounding epileptic cortices was performed. Postoperatively, he became seizure-free with antiepileptic medication during a 12-month follow-up period. Histological examination of the surgical specimen showed the characteristic findings of angiocentric glioma. Associated cortical dyslamination consistent with cortical dysplasia was found in the surrounding cortex. Angiocentric glioma is a slow-growing or stable tumor frequently presenting with intractable epilepsy. Surgical treatment would be aimed primarily at control of epilepsy. Complete lesionectomy usually results in postoperative seizure freedom, but the present case shows evidence for associated cortical dysplasia with this tumor entity. Careful pre-surgical evaluation for epilepsy is necessary to achieve better seizure outcome.

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