Intracranial aneurysms: role of multidetector CT angiography in diagnosis and endovascular therapy planning.

PURPOSE

To evaluate the sensitivity of 16-detector row computed tomographic (CT) angiography in diagnosis of intracranial aneurysms and to determine whether multidetector CT angiography provides sufficient diagnostic information to guide endovascular treatment, with combined imaging and clinical data as the reference standard.

MATERIALS AND METHODS

Institutional review board approval and informed consent were obtained. Eighty-seven patients clinically suspected of having subarachnoid hemorrhage underwent multidetector CT angiography and digital subtraction angiography (DSA). Aneurysm detection with multidetector CT angiography and DSA was analyzed on a per-patient and a per-aneurysm basis. For each aneurysm deemed ruptured on multidetector CT angiograms, the same multidetector CT angiography data set was used to determine whether the aneurysm was suitable for endovascular coil placement or whether a neurosurgical procedure was preferable. Criteria were based on neck width in relation to aneurysm size and the presence of vessels originating from the aneurysm. Results were compared with actual treatment that had been performed in each aneurysm after full diagnostic work-up, including DSA. Sensitivity, specificity, and positive and negative predictive values for aneurysm presence were determined.

RESULTS

The reference standard revealed 84 aneurysms in 63 patients. Multidetector CT angiography was used to correctly identify 62 of 63 patients with 80 of 84 aneurysms and to correctly rule out aneurysms in 24 patients. DSA was used to correctly identify 62 of 63 patients with 79 of 84 aneurysms and to correctly rule out aneurysms in 23 patients. Per patient, the sensitivity, specificity, and positive and negative predictive values, respectively, for presence of aneurysm(s) were 98%, 100%, 100%, and 96% for multidetector CT angiography and 98%, 100%, 98%, and 96% for DSA. Per aneurysm, the possibility of coil embolization was correctly assessed with multidetector CT angiography in 69 (93%) of 74 target aneurysms for acute occlusive treatment.

CONCLUSION

Multidetector CT angiography offers high diagnostic accuracy-equivalent to that of DSA-in the detection of intracranial aneurysms. Also, the possibility of coil embolization can be reliably determined with multidetector CT angiography.