OBJECTIVE: To evaluate the effects of a multimodal management technique combining surgical muscle wrapping, clipping, and flow-diverter stent (FDS) placement in patients with ruptured blood blister-like aneurysms (BBAs) in the internal carotid artery (ICA).
METHODS: In a retrospective case series review from 2020 to 2023, three patients with ruptured ICA BBAs underwent multimodal management, an approach combining muscle wrapping, surgical clipping, and FDS embolization. The aneurysm sac was initially packed and wrapped with multiple tailored temporalis muscle grafts and then secured using fenestration clips, with good preservation of the ICA branches. The FDS was placed 2-3 weeks after the clipping.
RESULTS: All three patients had right ICA BBAs (mean age, 52 years). The modified Hunt and Hess grades ranged from 2 to 3, and the Fisher grades ranged from 3 to 4. The mean angiography follow-up time was 27.7 months (15, 31, and 37 months). There were no instances of symptomatic vasospasm or visible ischemic stroke during follow-up computed tomography. No patient required cerebrospinal fluid shunt implantation, and all achieved favorable neurological outcomes (modified Rankin Scale 0-1). Follow-up digital subtraction angiography revealed no evidence of aneurysm recurrence or significant ICA stenosis.
CONCLUSIONS: We discuss a promising multimodal management approach for ruptured ICA BBAs combining muscle wrapping, surgical clipping, and FDS embolization. This technique was safe and effective in preventing re-rupture, achieving positive short-term clinical outcomes. Further research and more extensive studies are required to validate the long-term efficacy of this approach.
BACKGROUND:

Blood blister-like aneurysms (BBAs) are rare and challenging intracranial aneurysms. They pose significant diagnostic and surgical risks due to their delicate walls. Accounting for a small percentage of intracranial aneurysms, BBAs are pathologically pseudoaneurysms, often resulting from arterial dissection, with a high tendency to rupture. This report underscores the critical nature of BBAs by reviewing a case in which subarachnoid hemorrhage caused by a BBA rupture was difficult to diagnose with conventional imaging. We highlight the efficacy of three-dimensional (3D) high-resolution vessel wall imaging (VWI) in discerning the subtle vascular abnormality of BBAs. The integration of the black-blood imaging technique within VWI provides superior contrast between the aneurysm and surrounding tissues, facilitating clearer visualization of the aneurysmal wall. The use of 3D T1-weighted imaging provides intricate details of the vessel wall including its contrast enhancement, which is crucial for a comprehensive assessment of a ruptured aneurysm. This case is consistent with the existing literature, supporting the role of VWI in the identification of ruptured BBAs, an area with limited but growing information on its diagnostic value. VWI is precise and accurate in the preoperative diagnosis of BBAs, emphasizing its potential to improve patient management and outcomes, especially in conditions with high risks of morbidity and mortality.

Blood blister-like aneurysms (BBAs) are fragile and difficult to treat. However, the optimal treatment has yet to be determined. Pipeline embolization devices and Willis covered stent implementation are still controversial strategies for treating BBA. Herein, we report a case of recurrent BBA successfully treated with a Willis covered stent. A long-term follow-up angiography after the procedure indicated complete occlusion of the aneurysm. This case demonstrates the safety and efficacy of applying the Wills cover stent in the treatment of recurrent BBA after Pipeline implantation.

Blood-blister like aneurysms (BBAs) are challenging lesions because of their wide fragile neck. Flow-diverting stents (FDSs), such as the Pipeline Embolization Device (PED), have been applied to treat BBAs less amenable to more established techniques of treatment. However, the use of FDSs, including the PED, in acute subarachnoid hemorrhage (SAH) still remains controversial. We report a case of aneurysm regrowth following PED application for a ruptured BBA that overlapped the origin of the dominant posterior communicating artery (PCoA), which was successfully treated after coil trapping of the origin of the fetal-type PCoA. And, we discuss the clinical significance of the fetal-type PCoA communicating with a BBA in terms of PED failure.