gms | German Medical Science

Objective: Clear guidelines for angiographic controls after incomplete aneurysm clipping are missing. The aim of the present study was to evaluate the frequency of residual postoperative filling and the risk of re-growth of aneurysm remnants in a single center series.

Method: Between 03/2006 and 05/2012 292 patients underwent clipping of 384 ruptured or unruptured aneurysms. Control angiography (DSA) immediately after surgery was performed for every patient. Postop DSA findings were stratified in 1) completely occluded, 2) dog-ear residua, 3) significant remnant neck. Patients with completely clipped aneurysms underwent no further imaging controls. Patients with significant remnants were scheduled for DSA f/u. In cases with residual dog-ear further follow-up (f/u) proceeded depending on the size of the remnant, history of previous SAH, and clinical performance of patients.

Results: The immediate postop DSA revealed residual filling in 38 patients (9.9%), 8 of them were reoperated during the same hospital stay due to large residua. 33 (8.6%) patients were discharged with subtotally occluded aneurysms: dog ear n=12 (3.1%), residual necks n=21 (5.5%). The median remnant size in the non-dog ear group was 1.25 mm (range 0.5–4 mm). 16% (n=2) of patients with dog ear residua underwent f/u DSA whereas no changes in size or shape were observed (f/u: 6 and 16 months, respectively). In the group with significant residual necks f/u DSA was performed in so far 62% (n=13) with a median f/u of 13 months (range 3–68). 3 patients (14%) underwent re-treatment (re-clipping n=1, coiling of residual neck n=2): 2 patients (9.5%) due to re-growths (from initially 4 mm to 11 mm after 3 months, and from 1 mm to 4 mm after 12 months, respectively), 1 patient due to the flow alterations by unchanged size 11.5 months after the initial surgery. In 1 patient the initially 4 mm large remnant was thrombosed and no longer visible upon the DSA 19 months after surgery. During the current f/u, no rupture of aneurysm residua was observed.

Conclusions: Our study shows that the frequency of residual filling after clipping is relatively high (9.9%), therefore immediate DSA should be performed after every surgery. Concerning the observed risk of re-growth after incomplete clipping (9.5%) within the short period, f/u DSA should proceed at least in patients with significant residua.