Endovascular coil embolization of very small intracranial aneurysms.
BACKGROUND
Endovascular coil embolization of very small (maximum dome diameter ≤3 mm) aneurysms is controversial because of a high risk for procedural rupture and technical difficulty. We report clinical and angiographic results of coil embolization of these aneurysms.


METHODS
From August 2005 through July 2009, 43 very small aneurysms (23 ruptured, 20 unruptured) in 38 patients (12 males, 26 females; mean age, 53 years) were embolized with detachable coils. Of those 38 patients, 24 (63%) presented with subarachnoid hemorrhage (SAH) from a very small aneurysm (n = 23) or another aneurysm (n = 1). We assessed initial angiographic results, procedural complications, and clinical condition with initial Hunt and Hess grade (HH) and Glasgow outcome scale (GOS) at discharge. Follow-up results were evaluated with conventional angiography and/or magnetic resonance angiography (MRA).


RESULTS
Initial aneurysmal occlusion was total in 16 (37%), subtotal in 22 (51%), and partial in five (12%) aneurysms. There were five incidents of thrombosis (12%) and one procedural rupture (2%), but there was no definite adverse effect on clinical outcome. Of 24 patients with SAH, ten patients (42%) were in poor condition (HH 3 or 4) at admission. Seventeen of 24 patients (71%) had good or excellent outcome (GOS ≥4) at discharge. A 6-month or more follow-up angiography and/or MRA was available in 33 (11 total and 20 subtotal and 2 partial in initial occlusion) aneurysms (77%) in 28 patients and revealed stable occlusion in 20 aneurysms (61%), progressive total occlusion in 10 (30%), minor recanalization in 2 (6%), and major recanalization in 1 (3%).


CONCLUSIONS
Coil embolization of very small aneurysms may be technically feasible with favorable clinical/angiographic outcomes and relatively low recanalization rate during 6 months or more follow-up period.
Hwang
Jin Ho
JH
Department of Radiology, Konkuk University Medical Center, 4-12 Hwayang-dong, Gwangjin-gu, Seoul, 143-729, South Korea.
Roh
Hong Gee
HG
Chun
Young Il
YI
Kang
Hyun-Seung
HS
Choi
Jin Woo
JW
Moon
Won-Jin
WJ
Cho
Joon
J
Moon
Chang Taek
CT
Koh
Young Cho
YC
D000328:Adult; D000368:Aged; D017542:Aneurysm, Ruptured / Q000209:etiology / Q000628:therapy*; D021721:Balloon Occlusion / Q000009:adverse effects / Q000379:methods; D002533:Cerebral Angiography / Q000379:methods; D004621:Embolization, Therapeutic / Q000009:adverse effects / Q000379:methods; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D002532:Intracranial Aneurysm / Q000628:therapy*; D018810:Magnetic Resonance Angiography; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D013345:Subarachnoid Hemorrhage / Q000453:epidemiology / Q000209:etiology; D016896:Treatment Outcome