Case Series of Endovascular Therapy for Blood Blister-Like Aneurysm in Acute Phase

Abstract

Objective: Blood blister-like aneurysms (BBAs) of the internal carotid artery are highly challenging to treat due to their variable morphology and tendency for rupture and regrowth. Here, we report a single-institution experience of endovascular therapy (EVT) for BBA treatment.

Methods: We retrospectively reviewed patients with ruptured BBA from 2006 to 2019. All patients in whom BBA was treated with EVT were included. Patients' aneurysmal characteristics, progression status, aneurysm occlusion on follow-up angiography, and modified Rankin Scale (mRS) score were recorded.

Results: A total of 11 patients (5 women and 6 men) with the mean age of 46 ± 10 years were included in this study. As initial treatment, 9 patients were treated with stent-assisted coiling (SAC). Immediate angiographic results showed that 2 cases were body filling, 4 were neck remnant, and 3 were complete obliteration. Perioperative ischemic complications were not observed. On postoperative day 1, 2 patients suffered from rerupture, and their prognoses were poor. Retreatments were performed in 5 patients. Parent artery occlusion (PAO) was performed in 6 patients including 2 initial treatments and 4 retreatments. Symptomatic infarction developed in 2 patients. In 3 patients, bypass in combination with PAO was performed. Clinical data revealed discharge mRS scores of 0-2 and 3-6 in 4 and 7 patients, respectively.

Conclusion: SAC is effective for the management of BBA. Careful follow-up and response are necessary after treatment with SAC.

Keywords: blood blister-like aneurysm; endovascular therapy; overlapping stent; parent artery occlusion; stent-assisted coiling.

Fig. 1. Case 6 involved a 48-year-old woman with H&K grade 2 SAHs, which reruptured after SAC. (A) 3D reconstruction of the left ICA revealed a blood blister aneurysm. (B) Left ICA and right vertebral artery angiography. (C) A microcatheter for coil embolization was utilized via the posterior communicating artery. A microcatheter for stenting was utilized via the left ICA. (D) A microcatheter was jailed in the aneurysm with an Enterprise stent using the semi-jailing technique. (E) Immediate angiography showed CO. (F) Angiography after rerupture on postoperative day 1 showing a newly contrasted lesion on the side of the coil mass (arrowhead). CO: complete obliteration; H&K: Hunt and Kosnik; ICA: internal carotid artery; SAC: stent-assisted coiling; SAH: subarachnoid hemorrhage

Fig. 2. Case 8 involved a 54-year-old woman with H&K grade 2 SAHs treated with overlapping stent. (A) 3D reconstruction image of initial angiography showing an irregular bulge at the anterior wall of the right ICA. (B) Follow-up angiography at the 3rd postoperative day revealing an enlargement of the irregular bulging portion. (C) During the operation, a microcatheter was jailed in the sac neck with an LVIS stent using the semi-jailing technique. (D) Soft coils were inserted, and the stent was deployed to increase the metal coverage density of the sac neck. (E) Postoperative angiogram showing NR. (F) Follow-up angiography on the 13th postoperative day revealing a regrowth of the aneurysm. (G) Additional stent deployment was performed using a second LVIS stent. (H) Follow-up angiogram on the 3rd month postoperative showing CO. H&K: Hunt and Kosnik; ICA: internal carotid artery; NR: neck remnant; SAH: subarachnoid hemorrhage