Study Supports Neurointerventions With 1.5-mm Coils for Very Small Ruptured Aneurysms

September 23, 2015—In Interventional Neurology, Thanh N. Nguyen, MD, et al reviewed the clinical and angiographic outcomes of patients with very small ruptured aneurysms (≤ 3 mm) treated with 1.5-mm coils (2015;4:59–63). 

The investigators concluded that the 1.5-mm coil may be used in the endovascular treatment of patients with very small ruptured aneurysms, providing a temporary protection to the site of rupture in the acute phase. If necessary, bridging with elective clipping may provide definitive aneurysm treatment.

The background of the study is that very small ruptured aneurysms demonstrate a significant risk for procedural rupture with endovascular therapy. The 1.5-mm coils have been commercially available since 2007, allowing neurointerventionists to provide endovascular treatment for these cases.

This retrospective cohort study examined consecutive, ruptured, very small aneurysms treated with coil embolization at a single institution. From from July 2007 to March 2015, 81 aneurysms were treated acutely with coils in 78 patients presenting with subarachnoid hemorrhage. The longest linear aneurysm was recorded, even if the first coil was sized to a smaller transverse diameter. The investigators presented descriptive results. 

As summarized in Interventional Neurology, there were five patients with 3-mm aneurysms, of which the transverse diameter was ≤ 2 mm in three patients. In all five patients, a balloon was placed for hemostatic prophylaxis in case of rupture, and a single 1.5-mm coil was inserted for aneurysm treatment without complication. 

Complete aneurysm occlusion was achieved in one patient, residual neck in two patients, and residual aneurysm in two patients. Aneurysm recanalization was present in two patients with an anterior communicating artery aneurysm; a recoiling attempt was unsuccessful in one of these two patients caused by inadvertent displacement and distal coil embolization, but subsequent surgical clipping was successful. Another patient was retreated by surgical clipping for a residual wide-neck carotid terminus aneurysm. The investigators reported that one patient died of ventriculitis at 3 weeks after presentation; the four other patients had an excellent outcome with no rebleed at follow-up (mean, 21 months; range, 1–62).