Morphological aspects of blister aneurysms and nuances for surgical treatment

Microsurgical treatment of blood blister-like aneurysms: efficacy of clip-on-wrapping with autologous dura mater

OBJECTIVE

To present a consecutive 20-year series of blood blister-like aneurysms (BBAs) to show that clip-on-wrapping with a Y-shaped autologous dura mater enables treatment of BBAs with a low complication rate and a satisfactory curative result.

METHODS

A retrospective review was performed from patients with BBAs of the internal carotid artery (ICA) at the Affiliated Hospital of Qingdao University from 1999 to 2019. Diagnosis and treatment options were analyzed. Outcome was assessed using the modified Rankin scale (mRS).

RESULTS

A total of 30 patients with BBAs of the ICA were included. Among these patients, 20 patients underwent microsurgical treatment (15 patients were treated by clip-on-wrapping with a Y-shaped autologous dura mater), the other 10 patients underwent endovascular treatment. All patients presented with subarachnoid hemorrhage (SAH). Four angiograms were initially negative. For all patients, intraoperative rupture occurred in five cases, but no postoperative aneurysm rupture occurred in this series. Three cases with clinical or radiologic cerebral infarctions were observed. The outcome was favorable in 26 patients.

CONCLUSIONS

Clip-reinforced wrapping technique using a Y-shaped autologous dura mater may be an effective method for treating BBAs.

Single-Cell RNA Sequencing Reveals the Pathogenic Relevance of Intracranial Atherosclerosis in Blood Blister-Like Aneurysms

Background

Intracranial non-branching site blood blister-like aneurysms (BBA) are extremely rare and vicious. Their etiology remains elusive, and no molecular study has been carried out to reveal its pathogenic relevance to intracranial atherosclerosis. To investigate its transcriptomic landscape and underlying potential pathogenesis, we performed single-cell RNA sequencing with extensive pathological validation.

Methods

In total, 12,245 cells were recovered for single-cell RNA sequencing analysis from 1 BBA and 2 saccular intracranial aneurysms (IAs). Unbiased clustering using Seurat-based pipeline was used for cellular landscape profiling. Cellchat was used to understand intracellular communications. Furthermore, 10 BBAs and 30 IAs were retrospectively collected for pathological validations like scanning electron microscopy, H&E stain, Masson stain, Verhoeff Van Gielson stain, and immunofluorescence.

Results

Single-cell transcriptome profiled 14 total subclusters in 6 major groups, namely, 6 monocyte/macrophage clusters, 2 T&NK clusters, 3 vascular smooth muscle cell (VSMC) clusters, 1 dendritic cell, 1 B cell, and 1 endothelial cell cluster. The only mural cell identified in BBAs was VSMC-2 cluster, while mural cells in IAs comprise most clusters of VSMCs and endothelial cells. Upregulated genes in BBA-derived VSMCs are related to arterial mineralization and atherosclerosis, such as PTX3, SPP1, LOX, etc., whereas vasodilation and physiological regulatory genes such as MGP, ACTA2, and MYL9 were conversely enriched in conventional IA-derived VSMCs. Immune cells in the BBA were predominantly macrophages, with a low fraction of T&NK cells, while conventional IAs had a higher percentage of T&NK. Gene enrichment analysis suggested that macrophages in BBA were highly enriched in lipid metabolism as well as atherosclerosis. Ligand–receptor interaction suggested that secretory phosphoprotein 1 (also known as osteopontin) played a major role in mediating the intracellular communication between VSMC and macrophages, especially in BBA. Pathological experiments corroborate with the bioinformatic findings and further characterized BBAs as a thin-walled thrombotic aneurysm with severe atherosclerotic lesions, where ApoE+ macrophages and OPN+ mural cells are intimately involved in the inflammation process.

Conclusions

The preexisting intracranial atherosclerosis might predispose the parent artery to the pathogenic occurrence of BBAs. These data shed light on the pathophysiology of intracranial aneurysms and might assist in the further resolution of the complexity in aneurysm pathogenesis.

The surgical management of intraoperative intracranial internal carotid artery injury in open skull base surgery-a systematic review

Intraoperative internal carotid artery (ICA) injury during open skull base surgery is a catastrophic complication. Multiple techniques and management strategies have been reported for endoscopic skull base surgery; however, the literature on managing this complication in open skull base surgery is limited. To perform a systematic review and give an overview of the different techniques described to manage this complication intraoperatively, a systematic review was conducted in PubMed, Ovid Medline, Ovid Embase and Scopus for literature published until July 2021. Titles and abstracts were screened. Studies meeting prespecified inclusion criteria were reviewed in full. PRISMA guidelines were strictly adhered to. Out of 4492 articles, only 12 articles could be included, reflecting an underreporting of open skull base ICA injuries. Multiple techniques can be used depending on the location and size of the injury as well as the surgeon's experience. Described techniques include the following: a primary repair via a micro-suture or nonpenetrating clips; wrapping or plugging; coating; occlusion of the parent artery with or without a bypass; packing with further endovascular management. A treatment algorithm is proposed.

Application of the Willis covered stent in the treatment of internal carotid artery blood blister-like aneurysms

The optimal treatment for blood blister-like aneurysm (BBA) has not yet been determined, and BBA has a high recurrence rate after stent-assisted embolization. The purpose of the present study was to evaluate the safety and feasibility of patients with BBA rupture in the acute phase or patients with BBA who have recurrence after stent-assisted coil embolization. Eight patients (8 women, mean age 50.3 ± 3.7 years) who presented with ruptured BBA or recurrence BBA that had been treated by stent-assisted embolization (5 patients after primary treatment of stent-assisted embolization) were retrospectively reviewed. Clinical follow-up was performed at 1 year after endovascular treatment. All patients were successfully treated with the WCS, and immediate postoperative angiography showed that the aneurysms were completely isolated. The ophthalmic artery was covered by WCS in one patient; however, this patient did not show any clinical visual field or vision symptoms. Procedure-related complications such as aneurysm rupture, vasospasm, acute thrombosis, or thromboembolism did not occur in any case. All patients were followed up for 1 year after endovascular treatment, and they were in good condition without recurrence. One patient developed delayed bleeding at the right temporal lobe. All patients had good clinical prognosis (modified Rankin Scale score ≤ 2). WCS implantation may be a safe and feasible strategy for patients with BBA rupture in the acute phase and patients with BBA who have recurrence after stent-assisted coil embolization and is a promising option worth exploring.

Slip Clip after successful microsurgery of a blister aneurysm: Should bypass always be the first option?

Blood Blister-like aneurysms are intracranial non-saccular aneurysms with higher rupture risk due to its fragile wall. Diagnosis is performed in the acute phase of a subarachnoid hemorrhage. There are several treatment options based on reconstructive or deconstructive techniques. This paper aims to discuss the limitations of microsurgery clipping for a ruptured blister aneurysm. We report on a case of a female patient presented with a Fisher III subarachnoid hemorrhage. Cerebral angiography revealed an internal carotid artery blister aneurysm. Initially microsurgery clipping was successfully performed. However, after a few days the patient presented new subarachnoid hemorrhage. The new cerebral angiography showed growth of the previously clipped aneurysm, with displacement of the clip from the position adjacent to the artery. High-flow bypass was performed obtaining definitive treatment. This is a definitive approach for blister aneurysms. If microsurgery clipping is chosen, a strict follow-up is required due to the dynamic nature of this lesion and the chance of re-bleeding even after successfully clipping.

Meta-analysis on the treatment options and outcomes of carotid blood blister aneurysms

OBJECTIVE

Carotid blister aneurysms remain a formidable surgical challenge with varied surgical options. There have been significant advancements in the endovascular management of these aneurysms with the introduction of flow diverters. The comparative risk profiles for different endovascular options compared to surgical management of these lesions is not completely understood.

METHODS

The study is a comprehensive systematic review and meta-analysis on the treatment of carotid blood blister aneurysms. Pubmed searches were used to identify relevant articles and patient level data was extracted. Two and three group analyses were conducted comparing surgical and endovascular strategies and surgical, stent coil and flow diversion techniques respectively. Patient outcomes were graded on the modified Rankin Scale with a score of 2 or less defined as favorable.

RESULTS

In total, 83 studies (41 and 42 studies on surgical and endovascular interventions, respectively) with 1119 patients met our inclusion criteria. A statistically significant difference (at the 5% level of significance) in the effect among three different interventions was not found (Q = 3.41, p = 0.1815) under the random-effect model. Our results did show summary proportions of favorable outcomes were higher in the stent coil (0.87, 95% CI: 0.79 - 0.94) and flow diversion (0.87, 95% CI: 0.75 - 0.96) than that of surgery (0.76, 95% CI: 0.71 - 0.83).

CONCLUSIONS

Our results suggest a trend towards improved patient outcomes with endovascular techniques compared to surgical strategies but statistical significance was not achieved. We also found that endovascular techniques compare favorably. Increasing retreatments were found to negatively affect patient outcomes.

Comparison of clinical and histopathological characteristics of short-term progressive and non-progressive blood blister-like aneurysms

BACKGROUND

Many blood blister aneurysms (BBAs) have been documented with a rapid progression history in repeated angiography. The underlying mechanism and clinical significance remained elusive. This current study aims to clarify the clinical and histopathological differences between short-term progressive BBA and non-progressive BBAs.

METHODS AND MATERIALS

Eighty-one patients with BBAs were consecutively included for this single-center retrospective analysis. Clinical and radiological data on these patients were retrieved from 2017 to 2019. BBAs were defined as either progressive or non-progressive based on observed growth based on repeated imaging. Histopathological examinations of a saccular aneurysm, a progressive BBA, and a non-progressive BBA were conducted using representative aneurysm samples.

RESULTS

Among all enrolled patients, 26 of the them were identified with progressive BBAs, while the other 55 with non-progressive BBAs. Progressive BBAs were diagnosed significantly earlier in angiography (3.36 ± 0.61 vs. 6.53 ± 1.31 days, p < 0.05) and showed a higher presence rate of daughter sacs (61.5 vs. 38.2%, p < 0.05). Three different progression patterns were identified. BBAs that developed daughter sac enlargement are diagnosed significantly later than BBAs exhibiting other progression patterns. Patients with progressive and non-progressive BBAs exhibited similar overall clinical outcomes and incidence for complications. For patients with non-progressive BBAs, microsurgery appears to be inferior to endovascular treatment, while for patients with progressive BBAs, the short-term outcomes between microsurgery and endovascular treatment were identical. Histopathological analysis revealed that both subtypes shared a similar pseudoaneurysms structure, but non-progressive BBAs had more histologically destructed aneurysm wall with less remnant fibrillar collagen in adventitia.

CONCLUSIONS

Progressive and non-progressive BBAs may not be distinct pathological lesions but represent different stages during the BBA development. Early intervention, regardless of treatment methods, is recommended for salvageable patients with progressive BBAs, but microsurgery should be performed with caution for non-progressive BBAs due to increased surgical risk.

A Case Series of Double Bypass Technique Used for the Treatment of Internal Carotid Blood Blister-like Aneurysms in Patients in Poor Initial Neurological Condition at the Early Stage of Subarachnoid Hemorrhage

BACKGROUND

Optimal surgical treatment of blood-blister aneurysms (BBA) remains controversial. Some surgeons prefer clipping reconstruction while others favor primary bypass with trapping.

OBJECTIVE

To analyze of benefit of double bypass technique to surgical outcomes in patients with ruptured BBA in poor initial neurological condition (PINC).

METHODS

Retrospective analysis of clinical, radiological, and surgical data in 9 patients treated between January 2009 and December 2015. Intraoperative middle cerebral artery blood pressure (MCABP) measurement was used for selection of bypass procedure.

RESULTS

Seven patients presented with World Federation of Neurosurgical Societies (WFNS) subarachnoid hemorrhage (SAH) score 4 or 5. No pulse pressure in the MCA after internal carotid artery (ICA) clamping was found in 3 patients, although their ACoA or PCoA were well visualized on preoperative angiograms. By contrast, only a minimal drop in MCABP following ICA clamping was detected in two cases, although their collaterals were slim/nonvisualized on imaging. Although angiographic vasospasms were not observed in our patients, two of them experienced cerebral infarction, attributable more to the mass effect and postoperative ICA thrombosis than to SAH-induced vasospasm. There were 2 premature intraoperative ruptures, but no perioperative mortality, aneurysm recurrence, or rebleeding. Five patients with WFNS SAH score 4 or 5 achieved favorable outcomes.

CONCLUSION

Early double bypass technique guided by MCABP measurement and combined with trapping (or rarely clipping) seems to be a safe method with excellent long-term outcomes in patients in PINC. This study may thus contribute to the debate on the optimal treatment strategy for BBA.

Supraclinoid internal carotid artery blister-like aneurysms: hypothesized pathogenesis and microsurgical clipping outcomes

BACKGROUND

Blister-like aneurysms (BLAs) on the supraclinoid segment of the internal carotid artery (ICA) are an enigma of cerebrovascular disease. Neither has a definite pathogenesis been so far identified, nor have uniform treatment guidelines been established for them. Our aim was to develop a hypothesis regarding the evolution of BLAs according to their macroscopic morphologies and to evaluate the efficacy of microsurgical clipping.

METHODS

The clinical data and morphological features of 15 consecutive patients with 16 BLAs on the supraclinoid ICA were retrospectively reviewed. The treatment strategies were analyzed, and functional outcomes were evaluated using the modified Rankin scale (mRS). Favorable outcomes were defined as a mRS score of 0-2.

RESULTS

Morphologically, aneurysm growth with expansion of the aneurysm neck before the surgical procedure occurred in two ruptured and one unruptured aneurysm. Daughter bleb formation was observed in two ruptured and five unruptured aneurysms. A varied degree of parent artery sclerosis was observed in nine patients. Thirteen patients were treated with direct surgical clipping, one patient was treated with clipping and wrapping, and the remaining patient was treated with an encircling clipping graft. Favorable and unfavorable outcomes were observed in 13 and two cases, respectively. Follow-up angiograms revealed 4 cases of stenosis with respective degree of mild, 30%, 50%, and 80% without any neurological dysfunction.

CONCLUSIONS

We suggest a hypothesis that BLAs on the supraclinoid ICA may share different evolving mechanisms between ruptured and unruptured lesions. A majority of them can be reliably and safely obliterated by direct clipping technique, except for the aneurysms accompanied with severely atherosclerotic parent walls.

Ruptured Bilobed Basilar Artery Fenestration Aneurysm Treated with a WEB Device

Objective

To describe the technique of using a Woven Endo Bridge (WEB) device to treat a ruptured bilobed blister-like aneurysm (BLA) at the basilar artery (BA) fenestration.

Case Presentation

A previously healthy 66-year-old female presented at the emergency room with subarachnoid hemorrhage (SAH), centered around the brainstem. Unenhanced CT and CT angiography showed a BLA of a basilar fenestration limb. The angiogram confirmed the diagnosis. A WEB device was chosen to treat this rare and challenging aneurysm.

Conclusion

In this article, we describe the successful endovascular treatment of a SAH patient with a ruptured BLA at the basilar artery fenestration using a WEB device. And an overview of treatment options is provided.

A scoring system to discriminate blood blister-like aneurysms: a multidimensional study using patient-specific model

Presurgical discrimination of blood blister-like aneurysms (BBAs) can assist neurosurgeons in clinical decision-making. The aim of this study was to investigate the characteristics of BBAs and construct a useful tool to distinguish BBAs. This study reviewed patients with small/median, hemispherical, and wide-necked aneurysms of the internal carotid artery in our institution. BBAs were identified via their intraoperative findings. A hemodynamic analysis was performed using a patient-specific model. The independent risk factors of BBAs were investigated using a logistic analysis. A scoring system was then established to discriminate BBAs, in which its predicting value was analyzed using receiver operating characteristic (ROC) analysis. A total of 67 aneurysms comprising 21 BBAs were enrolled. Comparing features between BBAs and non-BBAs, statistical significances were found in the aspect ratio (AR), height-to-width ratio, aneurysm angle (AA), wall shear stress gradient (WSSG), and normalized wall shear stress average. A multivariate logistic analysis identified AR (OR = 0.29, p = 0.021), WSSG (OR = 1.54, p = 0.017) and AA (OR = 2.49, p = 0.039) as independent risk factors for BBAs. A scoring system was constructed using these parameters, effectively distinguishing BBAs (AUC = 0.931, p < 0.01). Our multidimensional scoring system may effectively assist in the discrimination of BBAs from wide-necked non-BBAs.

De Novo Blister Aneurysm Formation in 16 Days Associated with Mucorales Fungi

Although blister aneurysms represent a small percentage of all intracranial aneurysms, they are generally considered to be a more morbid and challenging entity than the more common saccular intracranial aneurysms. Despite this, the etiology of blister aneurysms is still unknown, though there are several theories. We present the case of a 54-year-old man who initially presented with vision loss and normal intracranial computed tomography angiography imaging. Only 16 days thereafter, he underwent rapidly progressive clinical decline, which was found to be due to the development and rupture of a de novo supraclinoidal blister aneurysm. Autopsy results showed fungal infection of the arterial wall by Mucorales fungi at the site of the aneurysm. Our case report supports the theory that blister aneurysms can be caused by fungal infection of the wall of the internal carotid artery.

Blister aneurysms of the internal carotid artery: Surgical treatment and management outcome from a single center experience

OBJECTIVE

Blood-blister aneurysms (BBAs) of the internal carotid artery (ICA) are rare entities, but clinically important cause of subarachnoid hemorrhage (SAH). Several surgical and endovascular strategies have been attempted for these heterogeneous lesions. In this study, the authors analyzed the treatment strategy and outcomes in a series of cases of ICA blister aneurysms treated microsurgically.

PATIENTS AND METHODS

We retrospectively reviewed 15 consecutive cases of patients harboring ruptured BBAs, microsurgically treated at our institution between 2014 and 2018. We performed an analysis of the clinical and surgical aspects, as well as post-operative angiograms and outcomes.

RESULTS

Fifteen patients were identified; 9 (60%) were female. The mean age of presentation was 43,8 years. Most patients presented in good clinical conditions (Hunt-Hess 1-3 = 86%). The most common Fisher grade at presentation was 3 (60% of cases). All patients underwent digital subtraction angiography (DSA), revealing broad-based aneurysms at non-branching sites on the dorsal wall of the ICA. Intraoperatively, BBAs were confirmed in all cases. The lesions were approached through pterional (11-73%) or lateral supraorbital (4-27%) craniotomy. Direct clipping was performed in all but one lesion, in which case the clip-wrapping technique was used. Final angiographic control revealed complete occlusion in 14 cases. One patient required reoperation due to residual aneurysm filling. At discharge, a good outcome (Glasgow Outcome Scale [GOS] 4 or 5) was observed in 12 (80%) patients. Three patients were discharged with a GOS of 3.

CONCLUSION

Blood-blister-type aneurysms are rare and challenging lesions. Preoperative knowledge and careful surgical planning can prevent poor clinical outcomes. Surgical treatment remains an effective and safe option in this context.

Clipping on Crossed Wrapping Method for Ruptured Blood Blister-Like Aneurysm of the Internal Carotid Artery: Technical Note and Long-Term Results

Background

We have been performing the clipping on crossed wrapping (COCW) method using 2 strips of cotton on patients with an internal carotid artery blood blister-like aneurysm (IC-BLA). This method is reliable in preventing the clips from slipping off and the aneurysm walls from being damaged during clipping, and it enables more appropriate and safer clipping. Here we report the technical details of this method and the long-term outcomes of patients receiving this procedure.

Methods

Fifteen of 1275 (1.5%) patients with a ruptured cerebral aneurysm who received treatment at the Saiseikai Kumamoto Hospital during the period from January 1, 1999, to December 31, 2016, had an IC-BLA. All 15 patients were treated with COCW, except for the first patient, who was treated using a single strip of cotton. The long-term outcome of the treatment was analyzed.

Results

The mean follow-up period was 74 months. The first patient experienced rerupture of an aneurysm 10 days after the operation. No complications or regrowth of an aneurysm were observed in the remaining 14 patients during the follow-up period, except for 1 patient who received a reoperation for the regrowth of an aneurysm. As the final outcome, the numbers of patients with a Modified Rankin Score of 0, 3, and 6 were 13, 1, and 1, respectively.

Conclusions

It is suggested that COCW is a treatment that enables safe and long-term management of lesions in IC-BLAs.

Case Report: Late Sequela of a Muslinoma Involving the Optic Chiasm

An 84-year-old woman presented with 3 months of vertical binocular diplopia and difficulty reading at near. She had a history of bilateral ophthalmic artery aneurysm repair involving use of muslin in the 1990s. The patient then developed bitemporal hemianopsia secondary to muslin-induced inflammation ("muslinoma") extending to the optic chiasm, which required surgical decompression. She had a persistent bitemporal hemianopsia but was stable for two decades after surgery. In 2017, the patient re-presented with double vision. Exam showed a non-paretic diplopia due to a small angle comitant right hypertropia attributed to the retinal hemi-field slide. Repeat imaging showed no new aneurysm or recurrent muslinoma. This case had originally been reported two decades ago and represents the longest duration of recurrent symptoms from muslin-related optochiasmatic arachnoiditis in the English language ophthalmic literature. Clinicians should be aware of the potential of delayed and recurrent symptoms or signs years or even decades after muslin wrapping of aneurysms.

The Blood Blister Like-aneurysm: Usefulness of Sundt Clip

Objective

Blood blister-like aneurysm (BBA) is a kind of dorsal wall aneurysm and it is small, sessile, fragile and hazardous because of its high mortality and morbidity. Many challenges tried to establish the management or strategy. But so far, there is no optimal treatment of choice for the BBA. In this article, 17 cases of the ruptured BBA in one institute were analyzed retrospectively. The operative options were correlated with surgical and clinical outcomes.

Materials and Methods

During 14 years between October, 2002 and October, 2016, 23 patients were treated for subarachnoid hemorrhage with ruptured dorsal wall aneurysms. There were various strategies for treatment and different outcomes revealed. BBA were 17 (74%) cases and 6 (26%) cases were saccular aneurysm. By excluding saccular aneurysm, BBA was sorted and classified with its morphological characteristics, and the outcome of treatment in each case investigated retrospectively.

Results

Among 17 BBA-cases, 8 cases get microsurgical operation by Sundt clip. 5 cases get operation by conventional Yasargil clip, 1 case treated by Yasargil clip with wrapping, and 2 cases underwent endovascular management with coiling, and 1 case was managed by endovascular trapping of involved internal cerebral artery. Clinical outcomes were analyzed with modified Rankin Scale, Glasgow outcome scale and post-operative complications.

Conclusion

As the optimal management, operation using Sundt clip had much significance in treatment BBA. And, a thorough analysis of the angiography is essential to prepare for the treatment of BBA.

Blister Aneurysms of the Internal Carotid Artery: Microsurgical Results and Management Strategy

BACKGROUND: Blister aneurysms of the supraclinoid internal carotid artery (ICA) are challenging lesions with high intraoperative rupture rates and significant morbidity. An optimal treatment strategy for these aneurysms has not been established.

OBJECTIVE: To analyze treatment strategy, operative techniques, and outcomes in a consecutive 17-year series of ICA blister aneurysms treated microsurgically.

METHODS: Seventeen patients underwent blister aneurysm treatment with direct clipping, bypass and trapping, or clip-reinforced wrapping.

RESULTS: Twelve aneurysms (71%) were treated with direct surgical clipping. Three patients required bypass: 1 superficial temporal artery to middle cerebral artery bypass, 1 external carotid artery to middle cerebral artery bypass, and 1 ICA to middle cerebral artery bypass. One patient was treated with clip-reinforced wrapping. Initial treatment strategy was enacted 71% of the time. Intraoperative rupture occurred in 7 patients (41%), doubling the rate of a poor outcome (57% vs 30% for patients with and without intraoperative rupture, respectively). Severe vasospasm developed in 9 of 16 patients (56%). Twelve patients (65%) were improved or unchanged after treatment, and 10 patients (59%) had good outcomes (modified Rankin Scale scores of 1 or 2).

CONCLUSION: ICA blister aneurysms can be cautiously explored and treated with direct clipping as the first-line technique in the majority of cases. Complete trapping of the parent artery with temporary clips and placing permanent clip blades along normal arterial walls enables clipping that avoids intraoperative aneurysm rupture. Trapping/bypass is used as the second-line treatment, maintaining a low threshold for bypass with extensive or friable pathology of the carotid wall and in patients with incomplete circles of Willis.

Current status of the treatment of blood blister-like aneurysms of the supraclinoid internal carotid artery: A review

Currently, the treatment of blood blister-like aneurysms (BBAs) of the supraclinoid internal carotid artery (ICA) is challenging and utilizes many therapeutic methods, including direct clipping and suturing, clipping after wrapping, clipping after suturing, coil embolization, stent-assisted coil embolization, multiple overlapping stents, flow-diverting stents, covered stents, and trapping with or without bypass. In these therapeutic approaches, the optimal treatment method for BBAs has not yet been defined based on the current understanding of BBAs of the supraclinoid ICA. Therefore, in this study, we aimed to review the literature from PubMed to discuss and analyze the pros and cons of the above approaches while adding our own viewpoints to the discussion. Among the surgical methods, direct clipping was the easiest method if the compensation of the collateral circulation of the intracranial distal ICA was sufficient or direct clipping did not induce stenosis in the parent artery. In addition, the clipping after wrapping technique should be chosen as the optimal surgical modality to prevent rebleeding from these lesions. Among the endovascular methods, multiple overlapping stents (≥3) with coils may be a feasible alternative for the treatment of ruptured BBAs. In addition, flow-diverting stents appear to have a higher rate of complete occlusion and a lower rate of retreatment and are a promising treatment method. Finally, when all treatments failed or the compensation of the collateral circulation of the intracranial distal ICA was insufficient, the extracranial-intracranial (EC-IC) arterial bypass associated with surgical or endovascular trapping, a complex and highly dangerous method, was used as the treatment of last resort.

Combined suture and clipping for the reconstruction of a ruptured blister-like aneurysm

Blister-like aneurysms of the internal carotid artery (ICA) present a severe therapeutical challenge. While several reconstructive techniques are in use in case of acute rupture sacrifice of the parent vessel may be required. We present a combined technique of micro-sutures and clip application to repair the parent vessel in an intraoperatively ruptured blister-like aneurysm. Following temporary trapping of an intraoperatively ruptured 7-mm blister-like aneurysm four 8-0 nylon sutures were applied to adapt the vessel walls and support the branches of subsequently applied mini-clips. The combination of micro-sutures and mini-clips might be a valuable alternative to direct clipping or suturing in some cases with intraoperative rupture of blister-like aneurysms.