BACKGROUND:
Treatment of very small unruptured intracranial aneurysms (VSUIAs, defined as ≤3 mm) can be indicated in selected circumstances. The feasibility and outcomes of endovascular therapy for VSUIAs have been recently published; however, the efficacy and complication rate of surgical clipping has not been reported in any large series to date.
OBJECTIVE:
We conducted a multicenter study to examine surgical outcomes for VSUIAs.
METHODS:
All consecutive patients undergoing surgery for a VSUIA in 4 neurosurgical centers between October 2001 and December 2012 were retrospectively analyzed.
RESULTS:
In the study, 183 patients (128 women, mean age 51.3 years) were treated with 190 procedures for a total of 228 aneurysms. Most were anterior circulation aneurysms (n = 215). The majority were directly clipped (n = 222, 97.4%), with coagulation or wrapping in the remainder. After 1 reoperation for incomplete clipping, postoperative imaging of 225 aneurysms confirmed complete occlusion in 221 (98.2%), 1 neck remnant (0.44%), and 3 partial occlusions (1.3%). Mortality was 0%. Early postoperative neurological deficit developed in 12 patients (6.6%); posterior circulation location was a significant risk factor for early neurological deficit (P < .001). Middle cerebral artery aneurysms had the lowest rate of postoperative deficits at 1.5% (P = .023). After the initial 30-day perioperative period, all deficits related to treatment of posterior circulation aneurysms recovered; overall neurological morbidity decreased to 2.7% with no mortality.
CONCLUSION:
VSUIA clipping is highly effective and is associated with a low morbidity rate. For VSUIAs selected for treatment, our data support surgical clipping as the modality of choice.
ABBREVIATIONS:
BA, basilar artery
DSA, digital subtraction angiography
M1, middle cerebral artery proximal segment
MCA, middle cerebral artery
mRS, modified Rankin Scale
SCA, superior cerebellar artery
SAH, subarachnoid hemorrhage
VSUIAs, very small unruptured intracranial aneurysms
