J Cerebrovasc Endovasc Neurosurg.  2016 Sep;18(3):229-233. 10.7461/jcen.2016.18.3.229.

Results of Endovascular Coil Embolization Treatment for Small (≤ 5 mm) Unruptured Intracranial Aneurysms

• Lee S
• Gong TS
• Lee YW
• Kim HJ
• Kweon CY

• KMID: 2355646
• DOI: http://doi.org/10.7461/jcen.2016.18.3.229

Abstract

OBJECTIVE
Researchers and clinicians have been unable to fully elucidate the natural course of and proper treatment for unruptured intracranial aneurysms (UIAs) smaller than or equal to 5 mm, particularly with regard to whether close observation or surgery is more appropriate. In this retrospective study, we evaluated the safety and efficacy of endovascular coil embolization of small (≤ 5 mm) asymptomatic UIAs by analyzing outcomes and complications associated with the procedure.
MATERIALS AND METHODS
We analyzed data from 150 patients with small asymptomatic UIAs (≤ 5 mm) treated with coil embolization between January 2011 and December 2015. Three-dimensional angiography was used to measure aneurysm size. We evaluated procedure-related morbidity and mortality, immediate post-operative angiographic results, brain computed thomography follow-up results on post-operative day one, and clinical progress.
RESULTS
UIAs occurred primarily in the anterior circulation area (142 cases, 94.67%), though eight patients exhibited UIAs of the posterior circulation. Following coil embolization, aneurysms with complete occlusion were observed in 137 cases (91.3%). Partial occlusion occurred in five cases (3.33%), while the procedure had failed in eight cases (5.33%). Procedure-related morbidity and mortality were five cases (3.33%) and zero cases, respectively.
CONCLUSION
The endovascular treatment of small asymptomatic UIAs is associated with good short-term outcomes without permanent neurologic complications as well as low overall complication and morbidity rates. Thus, the procedure should be considered for patients with smaller asymptomatic UIAs.

Keyword

Embolization; Endovascular procedures; Intracranial aneurysm; Morbidity

MeSH Terms

Aneurysm
Angiography
Brain
Embolization, Therapeutic*
Endovascular Procedures
Follow-Up Studies
Humans
Intracranial Aneurysm*
Mortality
Retrospective Studies

Figure

• 

  Fig. 1 Transfemoral cerebral angiograms in a 71-year-old male patient. The 3.6 mm × 3.3 mm unruptured intracranial aneurysm (UIA) is visible on the left posterior communicating artery. (A, B) Frontal and lateral views showing pre-embolization UIA. (C, D) Frontal and lateral views showing a totally occluded aneurysmal sac after coil embolization.

• 

  Fig. 2 Transfemoral cerebral angiograms in a 61-year-old female patient. The 4.9 mm × 2.7 mm UIA is visible on the right ophthalmic artery. (A, B) Frontal and lateral views showing pre-embolization UIA. (C, D) Frontal and lateral views showing a partially occluded aneurysmal sac after coil embolization.

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