Intracranial vertebral artery dissections: evolving perspectives

Spontaneous intracranial vertebral artery dissections presenting with subarachnoid hemorrhage

BACKGROUND

Vertebral artery dissection (VAD) is an infrequent source of subarachnoid hemorrhage (SAH), with a high mortality rate, primarily due to the risk of rebleeding both before and after medical intervention. This paper provides a comprehensive analysis of the anatomy, pathophysiology, clinical presentation, treatment strategies, and outcomes of intracranial vertebral artery dissections that result in subarachnoid hemorrhage.

METHODS

Comprehensive five-year literature review (2018-2022) and a retrospective analysis of patient records from our institution between 2016 and 2022. We included studies with a minimum of 5 patients.

RESULTS

The study incorporated ten series from the literature and 22 cases from CHUM. Key anatomical factors increasing the risk of VAD include the vertebral artery's origin from the aortic arch, asymmetry of the vertebral artery, and its tortuosity. Patients may display specific collagen and genetic abnormalities. The occurrence of VAD appears to be more prevalent in men. Those with a ruptured intracranial VAD typically show prodromal symptoms and present with severe SAH. Rebleeding within the first 24 h is frequent. While standard imaging methods are usually adequate for VAD diagnosis, they may not provide detailed information about the perforator anatomy. Treatment approaches include both deconstructive and reconstructive methods.

CONCLUSION

Ruptured VAD is a critical, life-threatening condition. Many patients have a poor neurological status at presentation, and rebleeding prior to treatment is a significant concern. Deconstructive techniques are most effective in preventing rebleeding, whereas the efficacy of reconstructive techniques needs more investigation.

Vertebral Artery Dissection in a Young Adult: A Case Report

Vertebral artery dissections (VAD) pose a significant risk for strokes, particularly in young adults. This case report details the presentation and management of a 48-year-old patient who was diagnosed with an extracranial VAD following cervical spine manipulation (CSM). The patient's symptoms included acute right-sided ataxia, giddiness, vertigo, nausea, vomiting, and persistent pain behind the right ear, prompting immediate evaluation. After ruling out acute intracerebral hemorrhages, a computed tomography angiogram (CTA) of the head and neck identified a severe narrowing of the right distal vertebral artery with a string sign at the level of the right C1 loop (V3 segment), indicating an extracranial VAD. This finding was further supported when ultrasound (US) imaging revealed a high resistance flow pattern in the right distal vertebral artery. Furthermore, T2 and diffusion-weighted magnetic resonance imaging (MRI) confirmed a 1.8 cm VAD/hematoma and a 1.4 cm acute/subacute infarct in the right posterior inferior cerebellar artery (PICA) territory. This research accentuates the importance of recognizing and addressing that neck pain can be a symptom of musculoskeletal dysfunction or could have neurovascular origins. In this case, the patient's neck pain may have been musculoskeletal or could have been due to a previous dissection. Thus, differentiation should be considered before cervical spine manipulation.

Craniovertebral junction aneurysms

OBJECTIVE

The course of the vertebral artery and its relationship to the C_0-1-2 structures render it particularly vulnerable to mechanical trauma. In the present study, we investigated the course of vertebral arteries along the craniovertebral junction (CJ) to cast light on the biomechanical aspects of aneurysm formation, focusing mainly on the relation of the vertebral artery injuries to the CJ bony landmarks. Herein, we report our experience with fourteen cases of craniovertebral junction vertebral artery (CJVA) aneurysms and their presentations, management, and outcomes.

MATERIALS AND METHODS

We extracted from 83 vertebral artery aneurysms only those 14 cases whose aneurysms were located at the C_0-1-2. We reviewed all medical records, including operative reports and radiologic images. We divided the CJVA into 5 segments and then carefully reviewed the cases, largely focusing on the CJVA segments involved in the aneurysm. Angiographic outcomes were determined by angiography, which was scheduled at 3-6 months, 1, 2.5, and 5 years postoperatively.

RESULTS

A total of 14 patients with CJVA aneurysms were included in the present study. 35.7 % had cerebrovascular risk factors, while 23.5 % had other predisposing factors such as an AVM, an AVF, or a foramen magnum tumor. Predisposing factors in the form of neck trauma, both direct and indirect, were identified in 50 % of cases. The segmental distribution of aneurysms was as follows: three (21.4 %) at CJV 1, one (7.1 %) at CJV 2, four (28.6 %) at CJV 3, two (14.3 %) at CJV 4, and four (28.6 %) isolated to the CJV 5 segment. Of the 6 indirect traumatic aneurysms, 1 (16.7 %) was located at CJV 1, 4 (66.7 %) were located at CJV 3 and 1 (16.7 %) was located at CJV 5. The 1/1 direct traumatic aneurysm (100 %) from the penetrating injury was located at CJV 1. 100 % of cases with cerebrovascular risk factors, the affected vessels were on the dominant side. 42.9 % of cases presented symptoms of a vertebrobasilar stroke. All 14 aneurysms were managed only endovascularly. 85.8 % of patients we implemented flow diverters only. 57.1 % of follow-up cases were completely occluded angiographically, and 42.9 % of cases were near-completely or incompletely occluded at 1, 2.5, and 5-year follow-ups.

CONCLUSIONS

The current article is the first report of a series of vertebral artery aneurysms located in CJ. Herein, the association of vertebral artery aneurysm, hemodynamics, and trauma is well established. We clarified all segments of the CJVA and showed that the segmental distribution of CJVA aneurysms significantly differs between traumatic and spontaneous cases. We showed that treatment with flow diverters should be the mainstay of CJVA aneurysm treatment.

Clinical and radiological risk factors for rupture of vertebral artery dissecting aneurysm: significance of the stagnation sign

OBJECTIVE

The aim of this study was to investigate the clinical and radiological factors associated with the rupture of a vertebral artery dissecting aneurysm (VADA) and to evaluate whether the stagnation sign is a significant risk factor for rupture of VADA.

METHODS

Clinical and radiological variables of 117 VADAs treated in a tertiary hospital from September 2008 to December 2020 were retrospectively reviewed. The stagnation sign is defined as the finding of contrast agent remaining in the lesion until the venous phase of angiography. Univariate and multivariate analyses were executed to reveal the associations between rupture status and VADA characteristics.

RESULTS

The rate of ruptured VADAs was 29.1% (34 of 117) and the stagnation sign was observed in 39.3% (46 of 117). Fusiform shape (OR 5.105, 95% CI 1.591-16.383, p = 0.006), irregular surface (OR 4.200, 95% CI 1.412-12.495, p = 0.010), posterior inferior cerebellar artery (PICA) involvement (OR 3.788, 95% CI 1.288-11.136, p = 0.016), and the stagnation sign (OR = 3.317, 95% CI 1.131-9.732, p = 0.029) were significantly related to rupture of VADA in multivariate logistic regression analysis.

CONCLUSIONS

This study showed that fusiform shape, irregular surface, PICA involvement, and the stagnation sign may be independent risk factors for the rupture of VADA. Therefore, when the potential risk factors are observed in unruptured VADA, more aggressive treatment rather than follow-up or medical therapy may be considered.

Postpartum Acute Basilar Artery Occlusion Secondary to Vertebral Artery Dissection. Case Report and Literature Review

Female patients in the peripartum and postpartum periods have an increased risk of stroke than nonpregnant women. Cerebrovascular complications of pregnancy represent a significant cause of maternal mortality and morbidity and are potentially disabling. Acute basilar artery occlusion secondary to spontaneous vertebral artery dissection in the postpartum period is an infrequent entity and a major diagnostic and treatment challenge. In the present case, a 37-year-old female patient, eight weeks after caesarean delivery, presented with a history of sudden cervical pain, followed by headache and dizziness. Some hours later, she was found unconscious by her family and was transferred to the emergency department, where a neurological status assessment suggested vertebrobasilar stroke. The imagistic workup revealed right vertebral artery dissection and basilar artery occlusion without constituted ischemic lesions. The patient underwent endovascular intervention with dilation of the narrowed vertebral artery and stent retriever basilar artery thrombectomy, with a favourable clinical outcome. This report first presents the details of this case and the relevant literature data on postpartum arterial dissections and the subsequent ischemic complications and available treatment options.

Vertebral artery dissection and associated ruptured intracranial pseudoaneurysm successfully treated with coil assisted flow diversion: A case report and review of the literature

Dissecting intracranial pseudoaneurysms (IPs) are associated with a high incidence of rupture and poor neurologic outcomes. Lesions in the posterior circulation are particularly malignant and pose even greater management challenges. Traditional management consists of microsurgical vessel sacrifice with or without bypass. Flow diversion (FD) in the setting of subarachnoid hemorrhage (SAH) represents a reconstructive treatment option and can be paired with coil embolization to promote more rapid thrombosis of the lesion. We report a case of a ruptured dissecting vertebral artery (VA) IP successfully acutely treated with coil-assisted FD. A 53-year-old male presented with a right V4 dissection spanning the origin of the posterior inferior cerebellar artery and associated ruptured V4 IP. The patient was treated with coil-assisted FD. Oral dual-antiplatelet therapy (DAPT) was initiated during the procedure, and intravenous tirofiban was used as a bridging agent. Immediate obliteration of the IP was achieved, with near-complete resolution of the dissection within 48 h. The patient made a complete recovery, and angiography at 6 weeks confirmed total IP obliteration, reconstruction of the VA, and a patent stent. The use of FD and DAPT in the setting of acute SAH remains controversial. We believe that coil-assisted FD in carefully selected patients offers significant advantages over traditional microsurgical and endovascular options. The risks posed by DAPT and potential for delayed thrombosis with FD can be effectively mitigated with planning and the development of protocols. We discuss the current literature in the context of our case and review the challenges associated with treating these often devastating lesions.

Involvement of Matrix Metalloproteinase 9 in Vertebral Arterial Dissection With Posterior Circulation Ischemic Stroke

Background

Spontaneous vertebral arterial dissection (VAD) is an important cause of posterior circulation ischemic stroke (PCS), but its pathogenesis remains elusive. Matrix metalloproteinase 9 (MMP‐9) is a gelatinase involved in inflammation process and several vascular diseases, such as aorta dissection, but its role in VBD is unclear yet. The present study aimed to determine the association between serum MMP‐9 level and VAD‐related PCS.

Methods and Results

We recruited 149 patients with PCS, of which 30 were VAD and 119 had other determined etiologies (non‐VAD), and 219 non‐stroke individuals. Serum MMP‐9 was measured within 14 days from stroke onset. The age of VAD group was 59.6±15.0 years, which is similar to non‐stroke group (P=0.510) but significantly younger than non‐VAD group (69.9±14.0 years, P<0.001). Males and vascular risk factors were significantly more prevalent in VAD and non‐VAD groups than non‐stroke group (P<0.001). Multivariate logistic regression analysis adjusting potential confounders revealed that every 100 ng/mL of serum MMP‐9 level increment significantly predicted VAD (versus non‐stroke group: odds ratio (OR), 4.572; 95% CI, 2.240–9.333, P<0.001; versus non‐VAD group: OR, 1.819; 95% CI, 1.034–3.200, P=0.038).

Conclusions

Patients with VAD‐related PCS had higher levels of serum MMP‐9 at the acute stage of stroke compared with non‐stroke individuals and PCS of other causes, supporting the potential involvement of extracellular matrix‐degrading protease in the mechanism of VAD, which leads to ischemic events.

Clinical Efficacy and Quality of Life Follow-Up of Reconstructive Endovascular Therapy for Acute Intracranial Vertebral Artery Dissection Aneurysms

Background: Intracranial vertebral artery dissection aneurysms (VADAs) may cause acute ischemia or hemorrhage, in which case urgent endovascular treatment will be needed. Although the majority of patients obtain a good functional outcome after surgery, a surprising finding has been a poor quality of life (QOL) in follow-up. The purpose of this study was to evaluate clinical efficacy in reconstructive endovascular therapy for acute intracranial VADAs and to analyze the factors contributing to subsequent QOL.

Methods: In this prospective study, 33 consecutive VADA patients with subarachnoid hemorrhage were recruited for comparison with 37 VADA patients with posterior circulation cerebral ischemia. All VADA patients were treated using a reconstructive strategy. Clinical, radiological, neurological, and cognitive data, as well as QOL, were assessed at admission and 6 months after surgery. Stoke Specific Quality of Life (SS-QOL) was evaluated for patients with good functional outcome [modified Ranking Scale (mRS) scoring 0-2] for subgroup analysis. Predictors for QOL at follow-up were analyzed by regression model.

Results: Immediate angiography after surgery showed complete VADA obliteration in 57 (81.4%) patients and partial obliteration in 13 (18.6%) patients. Three (4.3%) cases suffered from perioperative complications, comprising two cases of stent thrombosis in the hemorrhagic group and one case of posterior inferior cerebellar artery occlusion in the ischemic group. Twenty-five (75.8%) patients in the hemorrhagic group and 30 (81.1%) patients in the ischemic group had a favorable outcome (mRS scoring 0-2) at 6-month follow-up. Follow-up angiography displayed that one case of recurrence occurred separately in both groups. Fifteen of the 33 hemorrhagic patients (45.5%) and 19 of the 37 ischemic patients (51.4%) rated QOL at follow-up as bad (SS-QOL score ≤ 3.9) despite a good functional outcome. Severity of neurological disorder and impaired neurocognition at baseline in VADA patients are proved to be independent predictors for the decline of QOL according to regression analysis.

Conclusion: Reconstructive endovascular therapy for acute intracranial VADAs is a safe and effective method with a low complication rate. VADAs lead to impaired QOL at 6-month follow-up, which is attributable to multiple factors. This study demonstrated that neurological and cognitive status at baseline is of significant importance for QOL after VADAs.

Treatment outcomes in cerebral artery dissection and literature review

Methods Patients with cerebral artery dissections were reviewed in a hospital setting from 2008 to 2015. Clinical presentations, lesion locations, treatment modalities, functional outcomes, and mortality were reviewed. Parent artery occlusion was the first choice for surgery or endovascular treatment of a hemorrhagic dissecting cerebral artery. Endovascular or surgical reconstructive treatment was indicated in patients whose parent artery could not be occluded. Favorable functional outcomes were determined using modified Rankin Scale (mRS) scores of 0-2. Results In total, 61 patients with cerebral artery dissections were admitted to the hospital. Seven (11.5%) had traumatic dissections. All traumatic dissections were located in the internal carotid arteries. Overall favorable outcome rate was about 57% (4/7). Spontaneous cerebral artery dissections were found in 54 patients. No difference in favorable outcomes was observed between parent vessel occlusion and selective occlusion with parent vessel preservation (or vessel reconstruction) (70% and 63%, respectively, p = 1.000). Patients who presented with spontaneous dissection without intracranial hemorrhage had more favorable outcomes than those with intracranial hemorrhage (79% and 52%, respectively, p = 0.045). The mortality rate of patients with spontaneous dissection was 7.4%. Conclusions Most of the traumatic dissections were located on the internal carotid arteries and spontaneous dissections were commonly located on vertebral arteries. Nonhemorrhagic spontaneous cerebral dissections had better functional outcomes after treatment. Endovascular and surgical management were effective treatments by parent vessel occlusion or reconstructions.

Characteristics and Outcomes of Vertebrobasilar Artery Dissection with Accompanied Atherosclerosis

Background

With the popularity of MRI use, vertebrobasilar artery dissection (VBD) has been found more frequently in patients with posterior circulation ischemic stroke (PCS). The relationship between VBD and atherosclerosis is unknown. The present study aimed to prove the hypothesis that PCS with pure VBD (p-VBD) and with VBD and accompanied cervical or cerebral artery atherosclerosis (a-VBD) have distinct manifestations.

Methods

Patients with VBD-related PCS who were prospectively enrolled in the Taipei Veterans General Hospital Stroke Registry between January 1, 2010 and August 31, 2014 were recruited for the present study. Patients who had (1) atherosclerotic plaques with or without stenotic flow in cervical arteries on Duplex ultrasonography or (2) focal >30% stenosis in cerebral arteries other than the dissecting region (usually in arterial bifurcations which are prone to atheroma formation) on brain MRA were defined as a-VBD.

Results

There were 91 patients (67 [73.6%] males, mean age 65.5 years [SD = 15.2, range, 21–91]) with VBD-related PCS recruited for the present study; 31 were a-VBD and 60 were p-VBD. The results showed that there were significant differences in onset age, frequency of cigarette smoking, dissecting vascular involvement, and infarct locations between the 2 groups. In addition, compared with p-VBD, the a-VBD group had poorer functional recovery at 3 months and 1 year, respectively, which was independent of age, sex, vascular risk factors, stroke severity at admission, and treatment options.

Conclusion

VBD-related PCS with and without accompanied atherosclerosis had different manifestations and should be regarded as distinct arterial diseases.

Treatment of Cervical Artery Dissection: Antithrombotics, Thrombolysis, and Endovascular Therapy

Cervical artery dissection (CAD) is an important cause of stroke for young patients, accounting for 5–22% of strokes in patients <45 years of age, which presents not only a great burden to the stroke victims but also a financial burden to the family and society. Because CAD can lead to different clinical lesions, including neuropathy, acute ischemic stroke, and subarachnoid hemorrhage, and is an arterial dissection with a self-healing tendency, the treatment options depend on the clinical manifestations. The main purpose of the treatment is to control CAD-induced neuronal damage and to restore blood flow. The treatment programs include drug treatment and endovascular treatment. However, antithrombotic treatment is crucial. Both antiplatelet drugs and anticoagulant drugs are used to reduce the risk of stroke, but whether one treatment strategy is more effective than the other is unknown. The efficacy and timing of the endovascular treatment of CAD remain controversial.

Ruptured intracranial vertebral artery dissecting aneurysms: An evaluation of prognostic factors of treatment outcome

Objective Intracranial spontaneous vertebral artery dissecting aneurysms commonly occur in the third to fifth decades of life, and are mostly associated with hypertension. Patients present with intracranial haemorrhage or thromboembolic events. Patients who present with intracranial haemorrhage carry about a 70% risk of recurrent bleeding. Patients with a posterior-inferior cerebellar artery (PICA) or ipsilateral dominant vertebral artery involve selecting which parent vessel could not be sacrificed. Recent reconstructive techniques such as stent-assisted coiling embolisation and flow-diverting stents are effective treatments of choice. Methods Seventeen patients presented subarachnoid haemorrhage and nine patients with other symptoms. Sacrificing the parent vertebral artery was the first choice for surgical or endovascular methods. Endovascular reconstructive treatment by stent-assisted coiling embolisation was indicated in dissecting vertebral artery aneurysms with ipsilateral dominant vertebral artery or PICA involvement. Clinical outcomes were determined using the modified Rankin Score (mRS) at 90 days, with favourable outcomes defined as 0 to 2. Results Of the patients presenting with ruptured aneurysms, 11 (61.1%) had a good clinical outcome, with a mRS of 0-2. Favourable Hunt and Hess grading (65%), mild to moderate GCS (65%) and total occlusion of aneurysms after treatment (65%) were significantly good prognostic factors in patients with ruptured vertebral artery dissecting aneurysms. Conclusion Endovascular parent vessel sacrifice could be the first choice to treat a ruptured vertebral artery dissecting aneurysm. Stent-assisted coiling to preserve the patency of the parent artery and its branches is a promising treatment for vertebral artery dissections.

Traumatic injury to the posterior fossa

Traumatic injury to the posterior fossa is a complex pathologic condition because of the great heterogeneity of lesions present. Treatment of primary brain injuries and prevention of secondary brain injuries is the mainstay of management. It is imperative to recognize traumatic lesions of the posterior fossa early because of the occurrence of rapid neurologic decline. The decision regarding whether or not to proceed with surgical intervention depends on the patient's clinical condition, neurologic status, and imaging findings. Nonoperative management should be considered only if the patient is fully conscious and the associated posterior fossa lesions are small with little or no mass effect.

Endovascular interventional therapy and classification of vertebral artery dissecting aneurysms

The current study aimed to summarise the clinical features and classifications of vertebral artery dissecting aneurysms (VADAs) to optimise strategies for endovascular interventional therapy. The clinical features and results of 31 inpatients with VADA were retrospectively analysed. The aneurysms were classified according to their location and association between the aneurysm and posterior inferior cerebellar artery (PICA), and into subtypes according to the developmental state of the contralateral vertebral artery. Different endovascular interventional therapy strategies were selected for each classification. Three types of aneurysm with two subtypes each were identified. An aneurysm located distally to the PICA was termed type I (10/31 patients). Aneurysms with a contralateral vertebral artery were denoted as subtype a (type Ia, 6/31 patients) and aneurysms with hypoplasia of the contralateral vertebral artery were denoted as subtype b (type Ib, 4/31 patients). An aneurysm located at the origin of the PICA was termed type II (13/31 patients), with seven cases classified as IIa and six cases as IIb. An aneurysm located proximally to the PICA was termed type III (8/31 patients), with five cases classified as IIIa and three cases as IIIb. Among the 31 patients, 18 received stent-assisted coiling, two received coiling, 10 received coiling with parent artery occlusion and one patient received conservative treatment. Among the 31 patients with VADA, 21 were occluded completely, nine were partially occluded and one was not occluded. One patient developed a coma following coiling; however, the other 30 patients recovered well. Thus, the classification of an aneurysm based on its location and the developmental state of the contralateral vertebral arteries appears to be an effective and safe approach for the selection of appropriate endovascular interventional therapy strategies.