Role of Multislice Computerized Tomographic Angiography after Clip Placement in Aneurysm Patients Based on Comparison with Three Dimensional Digital Subtraction Angiography

OBJECTIVE: We evaluated the accuracy of multislice computerized tomographic angiography (MCTA) in the postoperative evaluation of clipped aneurysms by comparising it with three dimensional digital subtraction angiography (3D-DSA). METHODS: Between May 2004 and September 2006, we included patients with ruptured cerebral aneurysm of the anterior circulation that was surgically clipped and evaluated by both postoperative MCTA and postoperative 3D-DSA. We measured the diagnostic performance and calculated the sensitivity and specificity of postoperative MCTA compared to 3D-DSA in the detection of aneurysm remnants. RESULTS: A total of 11 neck remnants among the 92 clipped aneurysms (11.9%) were confirmed by 3D-DSA. According to Sindou's classification of aneurysm remnants, 8.7% of clipped aneurysms (8/92) had only neck remnant on 3D-DSA and 3.2% (3/92 aneurysms) had residuum of the neck and sac on 3D-DSA. There were 12 (13.04%) equivocal cases that were difficult to interpret based on the postoperative MCTA. The reasons for the equivocal cases included multiple clips (6 cases, 50.0%), beam-hardening effect (4 cases, 33.3%), motion artifact (1 case, 8.3%), fenestrated clip (1 case, 8.3%) and other combined causes. The sensitivity and specificity of the postoperative MCTA was 81.8% and 88.9%, respectively, by ROC curve (p=0.000). CONCLUSION: MCTA is an accurate noninvasive imaging method used for the assessment of clipped aneurysms in the anterior circulation. If the image quality of postoperative MCTA is good quality and the patient has been treated with a single titanium clip, except a fenestrated clip, the absence of an aneurysm remnant can be diagnosed by MCTA alone and the need for postoperative DSA can be reduced in a large percentage of cases.

Recurrent Sellar and Suprasellar Hemangiopericytoma

Hemangiopericytoma (HPC) is a rare tumor with uncommon location in the central nervous system. We report a rare case of sellar and suprasellar HPC mimicking pituitary adenoma in a patient initially seen with the symptoms of bitemporal hemianopsia, headache, and panhypopituitarism. Magnetic resonance imaging of the brain revealed a contrast-enhancing soft tissue mass arising from the pituitary fossa, with apparent compression of the chiasm and involving the cavernous sinus. Subtotal resection of the tumor was achieved via a pterional approach. Histopathological examination identified the tumor as a HPC. Nine years later, the tumor recurred. To our knowledge, this is the first reported case of sellar and suprasellar HPC in Korea.