Usefulness of multislice computerized tomographic angiography in the postoperative evaluation of patients with clipped aneurysms

Acta Neurochir (2010) 152:793–802 DOI 10.1007/s00701-009-0465-4

The aim of our study was to evaluate the diagnostic efficacy of multislice computed tomographic angiography (MSCTA) regarding exclusion quality after aneurysm clipping.
Methods. Sixty patients (74 aneurysms) underwent microsurgical exclusion using titanium clips. The presence of aneurysm remnants on MSCTA was compared by a neuroradiologist to 2D digital subtraction angiography (DSA), which was considered as a reference examination. The contribution of 3D DSA was assessed in a subpopulation of 29 patients (35 aneurysms).
Results. With 2D DSA, six aneurysm remnants (8%) were diagnosed, and only five (7%) by MSCTA. The specificity and sensitivity were 98.5 and 83%, respectively. MSCTA failed to demonstrate one large remnant (>2 mm) because of clip artifacts (six clips). With 3D DSA six supplementary remnants were diagnosed. Two were large remnants blinded by vessel overlaps and clip artifacts. Four were small “dogeared” remnants (≤2 mm). No additional treatment was required for small remnants.
Conclusion. In the postoperative period, MSCTA was considered a useful tool to evaluate the large remnants as well as a non-invasive ulterior examination for suspected bifurcation. Nevertheless, 3D DSA is still required for an accurate evaluation of aneurysms treated by more than three clips.