Aneurysms of the posterior circulation: detection and treatment planning using volume-rendered three-dimensional helical computerized tomography angiography.

OBJECT: The aim of this study was to determine whether computerized tomography (CT) angiography could be used to identify and characterize aneurysms of the posterior circulation and guide optimal treatment selection, and how data obtained using this method compared with intraoperative findings. METHODS: Patients suspected of harboring brain aneurysms underwent CT angiography and digital subtraction (DS) angiography; the results were prospectively interpreted by blinded independent evaluators. All patients with posterior circulation aneurysms were consecutively enrolled in the study. After treatment, neurosurgeons and endovascular therapists evaluated the ability of CT and DS angiography to demonstrate features of the lesions important for triage between treatment options (Wilcoxon signed-rank test) and to allow for coil or clip preselection and complete treatment planning (McNemar test of proportions), while using intraoperative findings as the basis of truth. In 242 patients overall, CT angiography detected 38 aneurysms and two aneurysmal blisters in 32 patients. The sensitivity of CT angiography in revealing posterior circulation aneurysms was 100% compared with DS angiography, with no false-positive results. Furthermore, CT angiography was sufficient as the sole study at triage for 65% of the posterior circulation aneurysms (26 of 40 lesions; p < 0.001), including 62% of the complex lesions (p < 0.001), and permitted coil or clip preselection in 74% of treated cases (20 of 27 cases; p < 0.002). Results of CT angiography revealed information about mural calcification and intraluminal thrombus not available on DS angiography, which affected patient care. CONCLUSIONS: In this study population, CT angiography was comparable to DS angiography in the detection and characterization of aneurysms of the posterior circulation. Computerized tomography angiography was used successfully to triage patients between endovascular and neurosurgical treatment options in a significant proportion of cases and permitted treatment planning in more than 70% of treated cases.

Survey of radiology residents: breast imaging training and attitudes.

PURPOSE: To investigate the training and attitudes of residents regarding breast imaging. MATERIALS AND METHODS: A telephone survey was conducted with 201 4th-year residents (postgraduate medical school year 5) and 10 3rd-year residents (postgraduate medical school year 4) at 211 accredited radiology residencies in the United States and Canada. Survey topics included organization of the breast imaging section, residents' role in the section, clinical practice protocols of the training institution, residents' personal thoughts about breast imaging, and their interest in performing breast imaging in the future. RESULTS: Of 211 programs, 203 (96%) had dedicated breast imaging rotations; 196 (93%) rotations were 8 weeks or longer; 153 (73%), 12 weeks or longer. Residents dictated reports in 199 (94%) programs. Residents performed real-time ultrasonography (US) in 186 (88%) programs, needle localization in 199 (94%), US-guided biopsy in 174 (82%), and stereotactically guided biopsy in 181 (86%). One hundred eighty-four (87%) residents rated interpretation of mammograms more stressful than they did that of other images, and 137 (65%) believed mammograms should be interpreted by subspecialists. One hundred thirty-five (64%) residents would not consider a fellowship in breast imaging if offered, and 133 (63%) would not want to spend 25% or more of their time in clinical practice on interpretation of mammograms. The most common reasons given for not considering a fellowship or interpretation of mammograms were that breast imaging was not an interesting field, that they feared lawsuits, and that it was too stressful. Fellowships were offered at 53 programs, and at 46 programs, a total of 63 fellows were recruited. CONCLUSION: Residency training in breast imaging has improved in terms of time and curriculum. However, a majority of the residents would not consider a fellowship and did not want to interpret mammograms in their future practices.

Detection and characterization of very small cerebral aneurysms by using 2D and 3D helical CT angiography.

BACKGROUND AND PURPOSE: Many cases of subarachnoid hemorrhage are due to rupture of small cerebral aneurysms. Our purpose was to evaluate the usefulness of helical CT angiography (CTA) in the detection and characterization of very small (<5 mm) intracranial aneurysms. METHODS: One hundred eighty consecutive patients underwent CTA for suspected intracranial aneurysms. All aneurysms prospectively detected by CTA were confirmed by digital subtraction angiography (DSA) or at surgery. CT angiograms and digital subtraction angiograms were reviewed by two independent blinded radiologists who performed aneurysm detection, quantitation, and characterization using 2D multiplanar reformatted and 3D volume-rendering techniques. RESULTS: Fifty-one patients harboring 41 very small intracranial aneurysms were included in this series. Eighty-one percent (33 of 41 aneurysms) were

Three-dimensional helical computerized tomography angiography in the diagnosis, characterization, and management of middle cerebral artery aneurysms: comparison with conventional angiography and intraoperative findings.

OBJECT: Middle cerebral artery (MCA) aneurysms can be difficult to detect and characterize. The authors describe the utility and impact of helical computerized tomography (CT) angiography for the evaluation of aneurysms in this location, and compare this modality with digital subtraction (DS) angiography and intraoperative findings. METHODS: Two hundred fifty-one patients with suspected cerebral aneurysms underwent CT angiography. Two-dimensional multiplanar reformatted images and three-dimensional CT angiograms were examined by two independent readers in a blinded fashion. Results were compared with findings on DS angiograms to determine the relative efficacy of these modalities in the detection and characterization of aneurysms. Questionnaires completed by neurosurgeons and endovascular therapists were used to determine the impact of CT angiograms on aneurysm management. Twenty-eight patients harboring 31 MCA aneurysms and 26 patients without aneurysms were identified using CT angiography. The sensitivity of CT angiography and DS angiography for MCA aneurysms was 97%; both techniques showed 100% specificity. In 76% of evaluations, the CT angiography studies provided information not available on DS angiography examinations. For the characterization of aneurysms, CT angiography was rated superior (72%) or equal (20%) to DS angiography in 92% of cases evaluated (p < 0.001). Computerized tomography angiography was evaluated as the only study needed for patient triage in 82% of cases (p < 0.001), and as the only study needed for treatment planning in 89% of surgically treated (p < 0.001) and in 63% of endovascularly treated cases (p < 0.001). The information acquired on CT angiograms changed the initial treatment plan in 24 (67%) of these 36 complex lesions (p < 0.01). The aneurysm appearance intraoperatively was identical or nearly identical to that seen on CT angiograms in 17 (89%) of 19 of the surgically treated cases. CONCLUSIONS: Computerized tomography angiography has unique advantages over DS angiography and is a viable alternative to the latter modality in the diagnosis, triage, and treatment planning in patients with MCA aneurysms.