MRI screening for acoustic neuroma without gadolinium: value of 3DFT-CISS sequence.

To evaluate the efficacy of a gradient-echo sequence (3DFT-CISS) in the diagnosis of acoustic neuromas, two independent observers twice reviewed the images of the temporal bones of 83 patients. Contrast-enhanced T1-weighted spin echo images were used as the reference, showing 18 acoustic neuromas, including 5 purely intracanalicular and one intralabyrinthine tumours. High sensitivity (89-94%), specificity (94-97%) and accuracy (94-95%) were found. Intraobserver (kappa 0.93-1) and interobserver (kappa 0.83-0.84) reproducibility were very good. The smallest intracanalicular tumour was overlooked twice by both observers; the intralabyrinthine tumour once by one observer. All tumours were detected with a less stringent decision criterion, at the expense of lower specificity.

Supra- and juxtarenal aneurysms of the abdominal aorta: preoperative assessment with thin-section spiral CT.

PURPOSE: To assess the contribution of thin-section spiral computed tomography (CT) to the preoperative radiologic evaluation of juxta- and suprarenal abdominal aortic aneurysms. MATERIALS AND METHODS: Thirty-eight patients (26 men, 12 women; age range, 60-81 years) with infrarenal (n = 23), juxtarenal (n = 8), and suprarenal (n = 7) aneurysms underwent digital subtraction angiography (DSA) and 2-mm-collimation spiral CT. Cine-interactive display of overlapping axial, reformatted, and maximum intensity projection images were used for CT image analysis. CT findings were compared with angiographic and surgical findings. RESULTS: The proximal extent of the juxta- and suprarenal aneurysms (n = 15) could be correctly predicted in 12 cases (80%) with DSA and was exactly determined in 14 (93%) with CT. All renal arteries except three accessory renal arteries were correctly depicted with spiral CT (83 of 86 [96%]). With DSA as the standard of reference, renal artery stenoses of at least 70% were accurately assessed in 95% of cases. CONCLUSION: Thin-section spiral CT can provide additional information in the preoperative diagnosis of juxta- and suprarenal aneurysms.

Assessment of accuracy of renal artery stenosis grading in helical CT angiography using maximum intensity projections.

The purpose of the study was to investigate whether visual inspection of maximum intensity projection (MIP) images is a reliable method for assessment of the severity of renal artery stenoses (RAS). Therefore, 20 RAS were investigated with helical CT. Native axial images and MIP images were analysed separately or in combination ("two-step method"). A phantom study was performed to investigate the influence of window setting on apparent stenosis severity. Accuracy for diagnosis of 50-69% and 70-99% RAS and the mean inter-observer agreement were 82.5%, 77.5% and 82.5% respectively, using study of MIP images alone, and 100%, 97.5% and 95% using the "two-step method". The phantom study showed that the apparent severity of vascular stenoses on MIP images depends on the selected window centre values. It is concluded that combined evaluation of both MIP images and native axial images is more reliable than study of MIP images alone for assessing the severity of RAS.

Right atrial tumor arising on an atrial septal aneurysm. Assessment by MR imaging.

An elderly women presenting with transient ischemic events underwent transesophageal echocardiography, which detected an aneurysm of the interatrial septum. A tumor protruding from the right atrial aspect of the aneurysm also was found incidentally. Not only was magnetic resonance (MRI) imaging helpful in better characterizing the aneurysm, but also the use of gadolinium diethylaminetriamine pentaacetic acid permitted differentiation between the tumor and adherent thrombus. To the best of our knowledge, this represents the first report of a tumor arising from an atrial septal aneurysm.

Intravascular ultrasonography, a new alternative for the assessment of vascular lesions.

Intravascular ultrasonography (IVUS) was performed in ten patients undergoing a diagnostic or therapeutic angiography. The ultrasound probe was inserted in a 6 French catheter and introduced through a 7 or 8 French sheath. Exact information was yielded about the extent of arteriosclerosis, the stenotic process and the composition of the atheromatous plaque (soft plaque or presence of calcifications). In the patients undergoing a percutaneous transluminal angioplasty, the status after dilation was also assessed, and intimal tears and residual atheromatous plaques could well be evaluated.

Percutaneous transluminal renal angioplasty versus renovascular surgery: statistical, medical and economical considerations.

Retro- and prospective comparative studies in patients with renal artery stenosis demonstrate that technical results and blood pressure improvement after renovascular surgery or percutaneous transluminal renal angioplasty (PTRA) are strictly comparable. The lesser invasive character of PTRA together with its lower complication rate and the lower cost explain why PTRA is the method of choice in the treatment of renal artery stenosis, with less restrictive selection criteria than used for surgery.