Objective: We wanted to evaluate the role of diffusion-weighted imaging (DWI) and the apparent diffusion coefficient (ADC) for detecting breast tumors, as compared with the T1-and T2-weighted images. Materials and Methods:Forty-one female patients underwent breast MRI, and this included the T1-, T2-, DWI and dynamic contrast-enhanced images. Sixtyfive enhancing lesions were detected on the dynamic contrast-enhanced images and we used this as a reference image for detecting tumor. Fifty-six breast lesions were detected on DWI and the histological diagnoses were as follows: 43 invasive ductal carcinomas, one mucinous carcinoma, one mixed infiltrative and mucinous carcinoma, seven ductal carcinomas in situ (DCIS), and four benign tumors. First, we compared the detectability of breast lesions on DWI with that of the T1-and T2-weighted images. We then compared the ADCs of the malignant and benign breast lesions to the ADCs of the normal fibroglandular tissue.

Background and Purpose-The incidence and risk factors for recurrence after endovascular treatment of intracranial vertebrobasilar dissecting aneurysms (VBDAs) have not been studied. We aimed to evaluate the incidence and risk factors for recurrence after endovascular treatment of VBDAs. Methods-A total of 111 patients (mean age, 45Ϯ10 years) underwent endovascular treatment for 119 VBDAs (ruptured/unrupturedϭ73:46). Incidence and risk factors for recurrence were retrospectively evaluated. Results-Sixty-two VBDAs were treated by a reconstructive technique by using 1 to 3 overlapping stents with or without coiling, and 57 VBDAs were treated by a deconstructive technique by using proximal occlusion or internal trapping at the dissected segment of the parent artery. Follow-up angiography was available for 97 VBDAs (81.5%) in 89 patients at 3 days to 48 months (median, 13 months) after treatment. There were 13 recurrences: 6 had rebleeding but 7 had no rebleeding. All 6 hemorrhagic recurrences had initially presented with a ruptured form. Ten recurrences were confirmed by angiography, but 3 recurrences with rebleeding did not receive follow-up angiography. The rate of post-treatment recurrence did not differ between reconstructive and deconstructive treatments. Involvement of the posterior inferior cerebellar artery origin (odds ratioϭ8.026; 95% confidence interval, 1.561 to 41.259; Pϭ0.013) was the only independent risk factor for recurrence. Conclusions-There was a 13% recurrence after endovascular treatment of VBDAs. Posterior inferior cerebellar artery origin involvement was the only independent risk factor for recurrence after endovascular treatment of VBDAs. (Stroke. 2011;42:2425-2430.)