Report of two cases of a rare cause of subarachnoid hemorrhage including unusual presentation and an emerging and effective treatment option

An unusual etiology of subarachnoid hemorrhage, basilar artery perforator aneurysms, in Macao: Three case reports and review of literature

BACKGROUND

Subarachnoid hemorrhage is a severe neurological condition that requires prompt and appropriate treatment to prevent complications. Aneurysms are the most common cause of spontaneous subarachnoid hemorrhage. Conversely, basilar artery perforator aneurysms (BAPAs) are a rare etiology. There is no consensus on the optimal management of ruptured BAPAs in the acute setting.

CASE SUMMARY

We present a case series of 3 patients with ruptured BAPAs who were treated at our institution. Two patients had a modified Fisher grade of I, and one had a grade of IV on initial presentation. The aneurysms were detected by computed tomography angiography in two cases and conventional angiography in one case. The 3 patients underwent endovascular treatment with Guglielmi detachable coils. Post-treatment, the patients had good clinical outcomes, and follow-up brain computed tomography scans showed reduced subarachnoid hemorrhage without any new hemorrhage. However, one patient experienced a cerebral infarction 2 months later and eventually succumbed to the condition. The other 2 patients showed progressive recovery, and no aneurysm recurrence was observed at the 2-year follow-up.

CONCLUSION

Endovascular treatment may be a preferable approach for managing ruptured BAPAs compared with surgical intervention or conservative management. Early detection and prompt treatment is important to achieve favorable patient outcomes.

Basilar artery perforator aneurysms: a comparison with non-perforator saccular aneurysms

BACKGROUND

Basilar artery perforator aneurysms (BAPAs) are rare. There is no systematic description of their presentation, imaging, natural history and outcomes and how these compare to conventional non-perforator aneurysms. Thus, the authors in this study aimed to compare BAPAs to non-perforator aneurysms.

METHODS

Cases were identified from a prospective neurovascular database, notes and imaging retrospectively reviewed and compared to a consecutive series of patients with non-perforator aneurysms. Blood volume on CT and vessel wall imaging (VWI) were compared to controls.

RESULTS

9/739 patients with aneurysmal subarachnoid haemorrhage (aSAH) harboured BAPAs. Compared to 103 with aSAH from posterior circulation aneurysms, they were more likely to be male (6/9, p = 0.008), but of equal severity (4/9 poor grade, p = 0.736) and need of CSF drainage (5/9, p = 0.154). Blood volume was similar to controls (30.2 ml vs 26.7 ml, p = 0.716). 6/9 BAPAs were initially missed on CTA. VWI showed thick (2.9 mm ± 2.7) bright enhancement (stalk ratio 1.05 ± 0.12), similar to controls with ruptured aneurysms (0.95 ± 0.23, p = 0.551), and greater than unruptured aneurysms (0.43 ± 0.11, p < 0.001). All were initially managed conservatively. Six thrombosed spontaneously. Three grew and had difficult access with few good endovascular options and were treated through a subtemporal craniotomy without complication. None rebled. At 3 months, all presenting in poor grade were mRS 3-4 and those in good grade mRS 1-2.

CONCLUSIONS

Despite their small size, BAPAs present with similar volume SAH, WFNS grade and hydrocephalus to other aneurysms. They are difficult to identify on CTA but enhance strikingly on VWI. The majority thrombosed. Initial conservative management reserving treatment for growth was associated with no rebleeds or complications.

Ruptured Basilar Artery Perforator Aneurysm Definitely Diagnosed with Intraoperative Microsurgical Findings: Case Report and Literature Review

Initial three-dimensional computed tomography and cerebral angiography fail to identify any aneurysm in 20% of cases of subarachnoid hemorrhage. Basilar artery (BA) perforator aneurysms are rare, and approximately 30%-60% were not identified by initial angiography. A 71-year-old male was transferred with a sudden onset of headache and loss of consciousness. Computed tomography demonstrated subarachnoid hemorrhage, but no ruptured aneurysm was detected. Repeat preoperative cerebral angiography indicated a bifurcation aneurysm of the circumflex branch of the superior cerebellar artery perforator, but microsurgical observation identified the BA perforator aneurysm. If the location of the BA perforator aneurysm cannot be clearly identified, as in this case, repeat angiography should be considered, and the treatment strategy should be decided based on a detailed consideration of the site of the aneurysm.

Transpetrosal Approach to a Ruptured Distal Basilar Perforating Artery Aneurysm

Basilar perforating artery aneurysms are rare and underreported vascular anomalies in the cerebrovascular literature. Various open and endovascular treatment approaches can be employed to treat these aneurysms based on several patient- and aneurysm-specific factors. Some authors have even advocated for conservative, nonoperative management. Here, we report a case of a ruptured distal basilar perforating artery aneurysm secured by an open transpetrosal approach. A 67-year-old male presented to our institution with a Hunt-Hess grade 2, modified Fisher grade 3 subarachnoid hemorrhage (SAH). Initial cerebral digital subtraction angiography (DSA) did not identify an intracranial aneurysm or other vascular lesions. However, the patient had a re-rupture event several days after presentation. DSA at this time revealed a posteriorly projecting distal basilar perforating artery aneurysm. Initial attempts with endovascular coil embolization were unsuccessful. Thus, an open transpetrosal approach was taken to gain access to the middle and distal basilar trunk to secure the aneurysm. This case underscores the unpredictability of basilar perforating artery aneurysms and the challenges encountered when considering active treatment. We demonstrate an open surgical approach with an intraoperative video for definitive management after failed attempted endovascular treatment.

Spontaneous subarachnoid hemorrhage caused by ruptured aneurysm of basilar trunk perforator: a case report and literature review

Background

Aneurysm of basilar perforator was rarely reported in the literature. It is difficult to treat due to its small size and deep-seated location. Excessive treatment may cause complications that resulted from ischemic events of parent perforators. Therefore, it is important to make clinical strategy for such patients to improve the prognosis.

Case presentation

One case, who presented as spontaneous subarachnoid hemorrhage, despite the negative result in computed tomography angiography firstly, was diagnosed angiographically as a ruptured aneurysm of the basilar perforator. A good clinical outcome of the case was achieved during the follow-up after conservative observation for 2 months, as well as the disappearance of previous lesion from angiography.

Conclusions

Aneurysm located at perforator of basilar trunk was rare and difficult to treat. Conservative observation for certain cases with periodic angiography follow-up was considered in order to prevent the patients from potential iatrogenic effects.

Comparison between stenting and conservative management of posterior circulation perforator aneurysms: Systematic review and case series

PURPOSE

Posterior circulation perforator aneurysms (PCPAs) are a rare type of intracranial aneurysms whose natural history and optimal clinical management are still largely unexplored. This study aims to report our experience with treating ruptured PCPAs and to provide a systematic review of the literature to compare the two most established treatment options, endovascular stenting, and conservative management including administration of antifibrinolytic drugs and watchful waiting.

METHODS

We performed a systematic review of the literature following the guidelines of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). Major databases were searched for case reports and case report series written in the English language between 1995 and 2020. Additionally, we retrospectively reviewed our stroke center database for cases of ruptured PCPAs between January 2014 and July 2020. Endovascular stenting and conservative treatment were compared using endpoints, including favorable outcome rate (mRS 0-2), occlusion rate, mortality rate, periinterventional complication rate, and re-hemorrhage rate.

RESULTS

We identified 31 patients treated endovascularly using stents and 33 patients treated conservatively, with the administration of antifibrinolytic drugs in 3 of them. Our analysis showed no statistically significant difference between the groups, except for the occlusion rate.

CONCLUSIONS

The optimal management strategy of PCPAs is still unknown, but stenting can be considered as an effective occlusion method with an acceptable complication rate. Preventive ventricular drainage may be necessary due to the high hydrocephalus rate encountered in ruptured PCPAs.

Ruptured Basilar Artery Perforator Aneurysm: A Case Report and Review of the Literature

Basilar artery perforator aneurysms (BAPAs) are a rare cause of subarachnoid hemorrhage (SAH), and the natural history is still unknown. Herein, we report a case of ruptured BAPA that appeared during the observation period and then spontaneously disappeared; we have also conducted a review of the literature and performed an analysis based on the type of management. This case of BAPA had a unique course, and our observations may help establish a treatment strategy. A 60-year-old man presented with acute diffuse SAH, World Federation of Neurosurgical Societies (WFNS) Grade II and Fisher Grade 3. Initial three-dimensional digital subtraction angiography (DSA) did not show the source of the hemorrhage. DSA performed on day 39 showed a BAPA with a diameter of 3 mm at the posterior surface of the upper third of the basilar artery. Conservative treatment was chosen. DSA performed on day 64 showed complete resolution of the aneurysm. BAPAs are likely pseudoaneurysms, and not saccular aneurysms, caused due to dissection of basilar perforator arteries. BAPAs are often not recognized on initial imaging, and hence, it is necessary to repeat the DSA examination. Considering the relatively high rate of spontaneous resolution, we chose conservative management. When BAPAs enlarge or do not disappear after conservative treatment, additional therapy such as multiple stents should be considered.

A systematic review of non-trunk basilar perforator aneurysms: is it worth chasing the small fish?

BACKGROUND AND PURPOSE

Non-trunk basilar artery perforator aneurysms (BAPAs) are rare intracranial vascular pathologies that have long been underdiagnosed, under-reported, and under-analyzed. We performed a systematic review of the efficacy and safety endpoints between conservative and active treatment approaches for non-trunk BAPAs.

METHODS

Major databases were analyzed for relevant publications between 1995 and 2019. Studies comparing the outcomes between conservative and active treatment approaches such as coiling, stenting, clipping, liquid embolization, and flow diversion were included. Mortality rate, rate of permanent neurological deficit as determined by the modified Rankin Score (mRS), rate of second treatment occurrence, and perioperative complication rate were also assessed.

RESULTS

A total of 24 studies, including 54 patients with 56 non-trunk BAPAs, were included. The mean maximum aneurysm diameter was 2.70 mm (range 1-10). A diagnosis was achieved with the initial DSA in 50.0% (27/54) of the patients. A conservative approach was used in 16 patients while active treatment was used in the other 38. Thirteen of 15 (86.7%) patients in the conservative group and 27/34 (79.4%) in the active treatment group had an mRS score 0-2. A non-significant higher odds of a positive outcome was observed in the conservative group (OR 1.51, 95% CI 0.50 to 4.54). The event-related mortality rate was 3.55% (3/54) with one procedure-related death in the active treatment group.

CONCLUSIONS

In patients with non-trunk BAPAs unamenable to active treatment, conservative approaches may result in acceptable functional outcomes and low morbidity. Small sample sizes and under-reporting of outcomes warrant further study.

Basilar artery perforator aneurysms: Report of 9 cases and review of the literature

Basilar perforator artery aneurysms (BAPA's) are an under-recognised cause of sub-arachnoid haemorrhage (SAH). We present our single centre experience of BAPA's and review of the literature. We performed a retrospective review of our prospectively maintained database to identify all BAPA's that presented acute SAH between February 2009 and February 2018. We identified 9 patients (male = 7), each with a single aneurysm, and average age 55 ± 9.7 years. All aneurysms were small, 2.1 ± 0.5 mm (range 1-3 mm). Three aneurysms were not detected on initial angiography. Six aneurysms were treated with flow diversion, 3 were managed conservatively. No repeat haemorrhage occurred in the flow diverted patients. One patient treated conservatively suffered a repeat haemorrhage and died (mRS 6). Follow up imaging (n = 7), at average 5.6 months (range 3-12 months), showed complete occlusion in all the flow-diverted aneurysms and no change in one conservatively managed patient. There was no evidence of perforator infarction on the follow-up post treatment imaging. Clinical follow-up data was available in 8 patients, 6 of whom (75%) had a good outcome (mRS ≤ 2). A high index of suspicion is required to diagnose BAPA. Flow diversion can be used to treat BAPA's with acceptable risk of perforator infarction and low risk of repeat haemorrhage.

Should we treat aneurysms in perforator arteries from the basilar trunk? Review of 49 cases published in the literature and presentation of three personal cases

Basilar trunk perforator artery aneurysms are rare. Their diagnosis and treatment are difficult, controversial, and challenging. Analysis of 52 cases (49 documented in the literature and three personal cases) clearly shows a re-bleeding rate of 15% in patients whose aneurysm has not been occluded and 0% in treated patients ( p < 0.05). The most effective treatment, and the one that presents the least complication, is double-stenting across the basilar trunk.

Super-selective coil embolization of a basilar perforator artery aneurysm previously treated by the stent-in-stent technique, using an extremely soft bare coil delivered through a one-marker microcatheter

Background Aneurysms of the perforating arteries arising from the basilar artery trunk are rare and represent a therapeutic challenge. Methods A basilar perforator aneurysm was initially treated by the stent-in-stent technique. Enlargement of the aneurysm was seen on follow up and the sac was secondarily coiled using two extremely soft bare coils, delivered through a one-marker microcatheter. Results At 6 months, the patient had a modified Rankin Scale score of 0 and cerebral arteriography demonstrated complete occlusion of the lesion. Conclusions We describe, as far as we are aware, the first case of basilar perforator aneurysm occlusion using extremely soft bare coils, inserted through the mesh of two stents previously placed in the basilar trunk.

Posterior circulation perforator aneurysms: a proposed management algorithm

INTRODUCTION

Subarachnoid hemorrhage (SAH) from posterior circulation perforator aneurysms (PCPAs) is rare and its natural history is unknown. Diagnosis may be difficult, acute management is poorly defined, and long-term recurrent SAH rates and clinical outcome data are lacking.

METHODS

We searched our institution's records for cases of PCPA rupture and analyzed patient demographics, Hunt and Hess (HH) grades, diagnostic imaging, management, and clinical outcomes. We conducted telephone interviews to calculate modified Rankin Scale (mRS) scores.

RESULTS

We identified 9 patients (6 male, 3 female) with a ruptured PCPA who presented to the University of Virginia Health System (Charlottesville, VA, USA) between 2010 and 2016. Median and mean ages were 62 and 63 years, respectively. Median HH grade was 3. Seven of nine (78%) PCPAs were angiographically occult on initial imaging and median time to diagnosis was 5 days. Three conservatively managed patients had a mean mRS score of 0.67 (range 0-1) at mean follow-up of 35.3 months. Antifibrinolytic therapy was administered to all conservatively managed patients without thrombotic complication. Six patients receiving endovascular treatment had a mean mRS score of 2.67 (range 0-6) at mean follow-up of 49.2 months. No cases of recurrent SAH were seen in the study.

CONCLUSIONS

The rarity of PCPA has precluded long-term clinical follow-up until now. Our experience suggests low recurrent SAH rates. Until further studies are performed, conservative management, possibly combined with antifibrinolytic therapy, may be a viable treatment with acceptable long-term outcome.

Basilar Perforator Aneurysms: Presentation of 4 Cases and Review of the Literature

OBJECTIVE

Basilar perforator aneurysms (BPAs) are rare lesions that present a therapeutic challenge. We present 4 cases of ruptured BPAs treated either conservatively or by flow diverter deployment and review the literature.

METHODS

Patients (age 78, 59, 53, and 62 years) presented with World Federation of Neurological Societies grade I-IV and Fisher grade 3-4 subarachnoid hemorrhage. Initial angiography results were normal in 3 patients and necessitated a second angiography. BPA diameter was 0.5-3 mm; BPAs were located in the mid-third of the basilar artery in 2 patients and the upper third in 2 patients.

RESULTS

All patients were managed conservatively. One patient experienced rebleeding 10 days after initial ictus, which required the deployment of a flow diverter in the basilar artery. One patient developed a severe spontaneous pontine ischemic stroke with severe quadriparesis and refused further imaging. He was clinically stable at 1-year clinical follow-up. The other 3 patients showed complete resolution of BPAs on control follow-up imaging.

CONCLUSIONS

Ruptured BPAs are rare lesions that may heal spontaneously or be associated with spontaneous ischemic brainstem stroke or rerupture. These lesions can be managed conservatively initially with flow diverter deployment the most suitable therapeutic alternative in selected cases. Larger studies are needed to fully understand the natural history and refine the therapeutic strategy for these lesions.

Basilar artery perforator aneurysms (BAPAs): review of the literature and classification

Basilar artery perforator aneurysms (BAPAs) are an uncommon subtype of perforating artery aneurysms, with only 18 published cases since their initial description in 1996 by Ghogawala et al To date, there are only seven published cases of ruptured BAPAs treated using endovascular techniques. Given the rarity of these aneurysms, the natural history and ideal approach to treatment has not been established. We describe a new endovascular approach to treating these aneurysms using staged telescoping stents, summarize all published cases of BAPAs, and present a unique classification system to enable future papers to standardize descriptions.

Ruptured basilar artery perforator aneurysms--treatment regimen and long-term follow-up in eight cases

INTRODUCTION

Basilar artery (BA) perforator aneurysms may lead to severe subarachnoid hemorrhage (SAH). The acute management is uncertain. The anatomic approach is challenging both for coiling and clipping, and flow diverter stenting may be dangerous due to the required antiplatelet therapy. We report on our experiences in eight patients.

METHODS

We retrospectively analyzed eight patients with ruptured BA perforator aneurysm, including clinical characteristics, imaging data, treatment regimen, clinical course, and long-term outcome.

RESULTS

Patients presented with major SAH and World Federation of Neurosurgical Societies (WFNS) scores of I in three, II in two, and V in three cases. In four patients, the aneurysm was detected in the initial angiography, in four only in follow-up angiography. Five patients were treated conservatively and three patients had endovascular therapy. In the conservative group, the aneurysm spontaneously thrombosed in three cases. One patient suffered from a re-SAH and stayed permanently dependent due to an associated perforator stroke (modified Rankin Scale (mRS) 5). The remaining four patients recovered well (mRS 0 and 1 in two cases, each) including three patients also exhibiting perforator strokes. Regarding the endovascular group, one parent vessel was an angioma feeder and embolized with Onyx. The second aneurysm spontaneously thrombosed periinterventionally. The third patient underwent coiling. Two parent vessels were occluded postinterventionally, resulting in perforator strokes. Final mRS scores were 0, 2, and 2, respectively.

CONCLUSION

Conservative management of ruptured BA aneurysms might be a first-line treatment option with common spontaneous aneurysm occlusion, low rate of re-SAH, and promising clinical outcome.

Subarachnoid hemorrhage secondary to forceful sneeze

Subarachnoid hemorrhage (SAH) is a relatively less common but important neurological condition comprising 5% of all the cerebrovascular accidents. In most populations the reported incidence is 6-7 per 100,000 person-years and one-third of survivors become dependent. It is a serious but potentially treatable cause of neurological morbidity. Multiple authors have identified the most unusual novel associations and triggers of subarachnoid bleeds over the past decade. We herein report a rare case of subarachnoid hemorrhage leading to focal neurological deficit in a middle aged man secondary to forceful sneeze.

Flow diverter stent treatment for ruptured basilar trunk perforator aneurysms

OBJECTIVE

Basilar trunk perforator (BTP) aneurysms are rare. Treatment options traditionally considered for these uncommon lesions have included direct surgery, endovascular therapy, or conservative management. Flow diverters represent a newer therapeutic option for BTP aneurysms but pitfalls and complications are unknown. We describe three patients with BTP aneurysms treated with flow diverter stents.

METHODS

All three patients had ruptured BTP aneurysms and, after loading doses of dual antiplatelet agents, underwent treatment with a flow diverter alone (two patients) or in combination with an intracranial stent (one patient).

RESULTS

Complications directly (two thromboembolic events) or indirectly (one hemorrhage at the external ventricular drain site, probably facilitated by the dual antiplatelet therapy) occurred in all three patients and resulted in permanent morbidity in one case. Imaging follow-up confirmed obliteration in all three patients, and no episodes of rebleeding from the aneurysms were observed at follow-up.

CONCLUSIONS

Flow diverters are effective in obliterating BTP aneurysms. However, given the challenges and complications encountered, especially in patients with ruptured lesions, their use must be carefully weighed against other available therapeutic modalities, including observation.

Spontaneous resolution of perforator aneurysms of the posterior circulation

The authors present the cases of 3 patients with ruptured perforator aneurysms of the posterior circulation. Patients were 39, 55, and 59 years old. None of the patients had relevant past medical or family history. All presented with World Federation of Neurosurgical Societies Grade I and Fisher Grade 2 or 3 subarachnoid hemorrhage. Initial angiography results were normal. A second cerebral angiogram in each case revealed a small (< 3 mm) aneurysm of perforator arteries of the posterior circulation. Patients were successfully managed conservatively. None of the patients developed symptomatic vasospasm, rebleeding, or hydrocephaly. Control angiograms at 3 months showed spontaneous resolution of the aneurysm in all cases. Rupture of perforator aneurysms of the posterior circulation is a rare condition and it may be underdiagnosed because of limitations of imaging techniques. Treatments can lead to complications in highly functional territories and should be considered wisely, especially due to the fact that the causes and natural history of such aneurysms are unknown and spontaneous healing remains a possibility.