Endovascular reconstruction for treatment of vertebrobasilar dolichoectasia: long-term outcomes

Safety and Efficacy of Low-Profile Braided Stents versus Flow Diverters in the Reconstructive Technique in the Treatment of Patients with Vertebrobasilar Dolichoectasia Aneurysms: A Cohort of 47 Patients with Long-Term Follow-Up

BACKGROUND AND PURPOSE

Vertebrobasilar dolichoectasia aneurysm is a rare type of cerebrovascular disorder with a poor natural history, and endovascular treatment is widely accepted. Whether a high-profile braided stent (flow diverter) could promote occlusion of vertebrobasilar dolichoectasia aneurysm without increasing the complications rather than a low-profile braided stent remains uncertain. The aim of the study was to present a single-center experience of the safety and efficacy of a low-profile braided stent versus a flow diverter in treating patients with vertebrobasilar dolichoectasia aneurysms.

MATERIALS AND METHODS

The retrospective review was conducted on a total of 432 consecutive patients diagnosed with posterior circulation aneurysms who underwent endovascular treatment in our center from August 2013 to December 2021. Among these patients, 47 individuals with vertebrobasilar dolichoectasia aneurysms who were treated with low-profile braided stents or flow diverters were included. Vertebrobasilar dolichoectasia aneurysms involving only the vertebral artery were excluded. Patients were divided into 2 groups: the low-profile braided stent group and the flow diverter group based on the device used. Safety and efficacy outcomes were subsequently analyzed.

RESULTS

There were 25 total patients enrolled in low-profile braided stent group and 22 patients in flow diverter group. The safety of low-profile braided stents and flow diverters in the treatment of vertebrobasilar dolichoectasia aneurysms was evaluated by clinical outcome, a new neurologic deficit due to procedural complications, and neurologic death. The rates of good clinical outcome were similar between the 2 groups (low-profile braided stent, 56%, versus flow diverter, 59.1%; P = .831), and the rates of neurologic death were also similar (low-profile braided stent, 12%, versus flow diverter, 9.1%; P = .747). Higher rates of new neurologic deficits due to procedural complications were observed in the flow diverter group, but the difference was not significant (low-profile braided stent, 24%, versus flow diverter, 40.9%; P = .215). The efficacy was evaluated by angiographic occlusion of vertebrobasilar dolichoectasia aneurysms and progression of mass effect resulting from these aneurysms. Significantly higher rates of complete occlusion of vertebrobasilar dolichoectasia aneurysms were shown in the flow diverter group (41.2%; P = .028) than in the low-profile braided stent group (10%).

CONCLUSIONS

Both low-profile braided stents and flow diverters have similar high risks in reconstructive techniques in the treatment of vertebrobasilar dolichoectasia aneurysms, while a flow diverter is more effective in promoting complete occlusion of vertebrobasilar dolichoectasia aneurysm than a low-profile braided stent. A flow diverter may be a better alternative for carefully selected patients with vertebrobasilar dolichoectasia aneurysms.

Endovascular Stent Implantation in the Treatment of Vertebrobasilar Dolichoectasia

Vertebrobasilar dolichoectasia (VBD) is a rare disease in clinic, with an incidence of 0.06% and 5.8%. It is a progressive vascular disease caused by the dilatation, tortuosity, and prolongation of vertebral and basilar arteries caused by a variety of factors. VBD can lead to hemodynamic changes, ischemic stroke, compression symptoms due to vasodilation, neurological dysfunction, hydrocephalus, subarachnoid hemorrhage, and other clinical manifestations. However, because the condition of VBD is complex and changeable, the treatment of VBD is not uniform. With the development of vascular intervention, especially the development of stent technology, it may become an effective method for the treatment of VBD. Two patients with VBD were treated with endovascular stent implantation.

Study on the relationship between vertebrobasilar dolichoectasia and posterior cranial fossa space

Objective

To investigate the correlation between vertebrobasilar dolichoectasia (VBD) and posterior cranial fossa (PCF) space.

Methods

The medical records and imaging data of patients with VBD and control group were collected from June 2021 to June 2022 in the Third People's Hospital of Hubei Province. All patients with VBD were graded by head and neck CTA. The grading index was divided into two parts, including vertebral artery bifurcation height and offset degree. Taking the healthy adult subjects of matched age as the control group. The linear volume of posterior cranial fossa was measured by median sagittal CTA images. Middle clivus length, transverse diameter of occipital foramen, supraoccipital length, sagittal diameter of posterior cranial fossa and height diameter of posterior cranial fossa was measured. The volume of the PCF was calculated by 3Dslice software. The relationship between VBD and the volume of PCF was analyzed by SPSS23.0.

Results

The height diameter of posterior cranial fossa, sagittal diameter of posterior cranial fossa, transverse diameter of occipital foramen, clival length, supraoccipital length and space volume of PCF were 34.78 ± 3.67 mm, 85.49 ± 4.15 mm, 30.89 ± 3.94 mm, 44.53 ± 5.36 mm, 45.21 ± 6.45 mm, 171.08 ± 15.81 cm3 in the case group. The linear volume of PCF and space volume of PCF were significantly lower than those in the control group (P < 0.05). Binary logistic regression analysis showed that the independent risk factors of VBD were height diameter of PCF, sagittal diameter of PCF, transverse diameter of occipital foramen, clival length, supraoccipital length and space volume of posterior cranial fossa. According to the classification, the height and diameter of PCF in grade 1 was significantly smaller than that in grade 2 VBD (P < 0.05). Under the standard of BA bifurcation degree, there were significant differences between different grades of VBD patients and age (P < 0.05).

Conclusion

The smaller volume of PCF may leading the greater possibility of VBD. Under the classification of VBD, the older, the longer the course of disease is, the higher degree of VBD classification is.

Wall enhancement predictive of abnormal hemodynamics and ischemia in vertebrobasilar non-saccular aneurysms: a pilot study

Objective

To analyze how wall enhancement affects hemodynamics and cerebral ischemic risk factors in vertebrobasilar non-saccular intracranial aneurysms (VBNIAs).

Materials and methods

Ten consecutive non-saccular aneurysms were collected, including three transitional vertebrobasilar dolichoectasia (TVBD). A wall enhancement model was quantitatively constructed to analyze how wall enhancement interacts with hemodynamics and cerebral ischemic factors.

Results

Enhanced area revealed low wall shear stress (WSS) and wall shear stress gradient (WSSG), with high oscillatory shear index (OSI), relative residence time (RRT), and gradient oscillatory number (GON) while the vortex and slow flow region in fusiform aneurysms are similar to TVBD fusiform aneurysms. With low OSI, high RRT and similar GON in the dilated segment, the enhanced area still manifests low WSS and WSSG in the slow flow area with no vortex. In fusiform aneurysms, wall enhancement was negatively correlated with WSS (except for case 7¹, all p values  < 0.05, r = -0.52 ~ -0.95), while wall enhancement was positively correlated with OSI (except for case 5, all p values < 0.05, r = 0.50 ~ 0.83). For the 10 fusiform aneurysms, wall enhancement is significantly positively correlated with OSI (p = 0.0002, r = 0.75) and slightly negatively correlated with WSS (p = 0.196, r = -0.30) throughout the dataset. Aneurysm length, width, low wall shear stress area (LSA), high OSI, low flow volume (LFV), RRT, and high aneurysm-to-pituitary stalk contrast ratio (CRstalk) area plus proportion may be predictive of cerebral ischemia.

Conclusion

A wall enhancement quantitative model was established for vertebrobasilar non-saccular aneurysms. Low WSS was negatively correlated with wall enhancement, while high OSI was positively correlated with wall enhancement. Fusiform aneurysm hemodynamics in TVBD are similar to simple fusiform aneurysms. Cerebral ischemia risk appears to be correlated with large size, high OSI, LSA, and RRT, LFV, and wall enhancement.

Case report: Late in-stent thrombosis in a patient with vertebrobasilar dolichoectasia after stent-assisted coil embolization due to the discontinuation of antiplatelet therapy

Vertebrobasilar dolichoectasia (VBD) is a rare type of cerebrovascular disorder with high rates of morbidity and mortality. Due to the distinct pathological characteristics that fragmented internal elastic lamina and multiple dissections, VBD is difficult to treat and cured. Stent-assisted coil embolization is one of the main treatment modalities for such lesions. However, the duration of healing remained questionable, and there were no effective measures for evaluating endothelial coverage. Before complete endothelial coverage, the discontinuation of antiplatelet therapy may lead to fatal in-stent thrombosis; however, continued antiplatelet therapy could also result in bleeding complications. Thus, we present an autopsy case of late in-stent thrombosis due to the discontinuation of antiplatelet therapy and systematically review the literature to provide a reference for endovascular treatment and antiplatelet regimen of VBD.

Flow Redirection Endoluminal Device Flow Diverter Placement for Recurrent Dolichoectatic Vertebrobasilar Artery Aneurysm Treated with Multiple Low-Profile Visualized Intraluminal Support Stents: A Case Study

Objective

We report a case of dolichoectatic vertebrobasilar aneurysms treated with multiple low-profile visualized intraluminal support (LVIS) stents followed by flow redirection endoluminal device (FRED) flow diverter to prevent the growth of the thrombosed aneurysm.

Case Presentation

A 71-year-old man developed diplopia due to oculomotor nerve palsy after 11 years of follow-up for an enlarging thrombosed dolichoectatic vertebrobasilar artery aneurysm. He initially had a fusiform thrombosed aneurysm from the right vertebral artery to the basilar artery. This lesion was tortuous and strongly compressed the pons. A total of 11 LVISs were deployed from the right posterior cerebral artery to the right vertebral artery. Six months after surgery, there was no enlargement of the thrombosed aneurysm on MRI and the contrast leakage out of the stent was markedly reduced in DSA compared to immediately after surgery. One year and seven months after surgery, contrast leakage out of the stent was increased in DSA. The FRED was placed within the overlapped LVISs, and contrast leakage was somewhat reduced. After 2 years and 7 months from the initial treatment, the contrast leakage was still observed. However, there was no enlargement of the aneurysm and no complications related to treatments were observed.

Conclusion

Treatment with multiple LVIS stents followed by FRED flow diverter treatment for dolichoectatic vertebrobasilar aneurysms (DVAs) may be one of the treatment options for controlling the growth of thrombotic aneurysms without complications, but the long-term prognosis of this case is unclear, and careful follow-up is mandatory.

Prospects and Dilemmas of Endovascular Treatment for Vertebrobasilar Dolichoectasia

Vertebrobasilar dolichoectasia (VBD) is characterized by significant expansion, elongation, and tortuosity of the basilar artery and vertebral artery. Certain highly selected cases of VBD can require intervention. Recent advances in endovascular treatment (EVT) have renewed hope for patients with VBD. However, which cases of VBD can benefit from EVT still needs to be determined. Currently, little is known regarding this matter. Therefore, we performed a review of the literature from a PubMed search and cataloged our experience regarding the classification and natural history of VBD and the prospects, prognosis and complications of EVT. The findings can be summarized as follows: for asymptomatic VBD, “wait and see” or medical management may be a reasonable strategy. EVT may only be effective in certain patients. For saccular aneurysms in VBD, especially ruptured aneurysms, EVT is reasonable. For fusiform aneurysms in VBD, EVT can carry high complication rates and should be recommended with caution. For stenting reconstruction in VBD, the effect is uncertain. For the future of EVT of VBD, randomized controlled trials and the development of neurointerventional products are worth pursuing, but EVT in VBD still has a long way to go.

Hemifacial spasm due to vertebral artery dissecting aneurysm treated with stent-in-stent placement; Pre- and post-treatment evaluation by 3D multifusion imaging using silent MR angiography

Background:

Hemifacial spasm (HFS) due to vertebral artery (VA) dissecting aneurysm (VADA) is rare and endovascular treatment has been performed in selected cases.

Case Description:

We encountered a case of HFS caused by VADA that was managed with endovascular stent placement and additional stent-in-stent placement. Therapeutic strategies and benefits based on pre- and post-treatment evaluation by 3D multifusion imaging using silent MRA were discussed.

Conclusion:

This is the first case report of stent-in-stent placement in successful treatment of HFS caused by VADA, in which relief of neurovascular contact was demonstrated by multifusion imaging.

Atorvastatin for unruptured intracranial vertebrobasilar dissecting aneurysm (ATREAT-VBD): protocol for a randomised, double-blind, blank-controlled trial

INTRODUCTION

Vertebrobasilar dissecting aneurysms (VBDAs) are associated with serious complications and a poor prognosis. It is believed that inflammation of the aneurysm wall may be the main cause of rupture or deterioration. Atorvastatin has been shown to inhibit inflammation and may be a suitable drug candidate. Here, we report a clinical research study protocol to investigate whether atorvastatin inhibits inflammation of the aneurysm wall, as measured by signal index enhancement.

METHODS AND ANALYSIS

We have designed a single-centre, randomised, double-blind, blank-controlled clinical trial. 40 patients with non-ruptured VBDAs with enhancement aneurysm walls will be enrolled in Beijing Tiantan Hospital. Eligible patients will be randomly divided into two treatment groups, at a ratio of 1:1, to receive atorvastatin 20 mg orally for 6 months or no treatment. The primary assessment outcome will be the change in aneurysm wall enhancement, as measured by the signal index during the 6-month treatment period. The secondary assessment outcomes will be the aneurysm morphology (intramural haematoma, dissection valve and false lumen) and changes in the concentrations of inflammatory factors, including C reactive protein, tumour necrosis factor-α, interleukin (IL)-1β and IL-6.

ETHICS AND DISSEMINATION

The protocol has been approved by the medical ethics committee of the Beijing Tiantan Hospital at which the work will be conducted (Approval No. KY 2019-024-02). Written informed consent will be obtained from all participants. Findings from the study will be submitted for publication in a peer-reviewed journal.

TRIAL REGISTRATION NUMBER

NCT04943783.

Pipeline Embolization Device With Adjunctive Coils for the Treatment of Unruptured Large or Giant Vertebrobasilar Aneurysms: A Single-Center Experience

Objective: To evaluate effectiveness and safety of Pipeline embolization device (PED) for large or giant verterbrobasilar aneurysms (LGVBAs), and to compare the therapeutic effects of PED with and without adjunctive coils. Methods: We retrospectively analyzed 21 cases of unruptured LGVBAs who were treated in our hospital with PED. These cases were divided into "PED group" and "PED with adjunctive coils group." We compared the aneurysm characteristics and treatment outcomes between the two groups. Results: The overall neurological complication rate was 28.6% (6/21) and the mortality rate was 4.8% (1/21). There were 12 patients in the PED group and nine in the PED with adjunctive coils group. There were no significant differences in age, smoking, hypertension, aneurysm size, aneurysm location, or operation time between the two groups. The complete aneurysm embolization rate and favorable outcome rate (modified Rankin Scale = 0,1) of the PED with adjunctive coils group was 78% (7/9) and 100% (9/9), respectively, which were both better compared with the PED group with 63.6% (7/11) and 83% (10/12), respectively. However, these differences were not statistically significant. Conclusion: The effectiveness and safety of PED for LGVBAs is acceptable. Treatment results did not differ between the PED and PED with adjunctive coils groups; therefore, whether coils should be used may depend the operator. Our results suggest that correct use of the coils does not increase complications. We suggest that PED with adjunctive coils should be used for some selected LGVBAs.

Absence of pontine perforators in vertebrobasilar dolichoectasia on ultra-high resolution cone-beam computed tomography

Background

Vertebrobasilar dolichoectasia (VBDE) is a rare type of non-saccular intracranial aneurysm, with poor natural history and limited effective treatment options. Visualizing neurovascular microanatomy in patients with VBDE has not been previously reported, but may yield insight into the pathology, and provide important information for treatment planning.

Objective

To carry out a retrospective analysis of ultra-high resolution cone-beam computed tomography (UHR-CBCT) in patients with fusiform basilar aneurysms, visualizing neurovascular microanatomy of the posterior circulation with a special focus on the pontine perforators.

Methods

UHR-CBCT was performed in seven patients (mean age 59 years; two female) with a VBDE, and in 14 control patients with unrelated conditions.

Results

The mean maximum diameter of the fusiform vessel segment was 28 mm (range 19–36 mm), and the mean length of the segment was 39 mm (range 15–50 mm). In all patients with VBDE, UHR-CBCT demonstrated an absence of perforating arteries in the fusiform arterial segment and a mean of 3.7 perforators arising from the unaffected vessel segment. The network of interconnected superficial circumferential pontine arteries (brainstem vasocorona) were draping around the aneurysm sac. In controls, a mean of 3.6, 2.5, and 1.2 perforators were demonstrated arising from the distal, mid-, and proximal basilar artery, respectively.

Conclusions

The absence of pontine perforators in the fusiform vessel segment of VBDE is counterbalanced by recruitment of collateral flow from pontine perforators arising from the unaffected segment of the basilar artery, as well as collaterals arising from the anterior inferior cerebellar artery/posterior inferior cerebellar artery and superior cerebellar artery. These alternative routes supply the superficial brainstem arteries (brainstem vasocorona) and sustain brainstem viability. Our findings might have implications for further treatment planning.

Serum level of lipoprotein-associated phospholipase A2 is a potential biomarker of vertebrobasilar dolichoectasia and its progression to cerebral infarction

BACKGROUND

There are no effective therapies to prevent the occurrence and progression of vertebrobasilar dolichoectasia (VBD). In this study, we investigated the relationship between serum levels of lipoprotein-associated phospholipase A2 (Lp-PLA2) and the occurrence and progression of VBD.

METHODS

Sixty (60) cases without VBD and ischemia stroke were considered as Group A, 100 cases with VBD were further divided into Group B (VBD without ischemic stroke, n = 54) and Group C (VBD with first ever acute posterior circulation ischemic stroke, n = 46). Demographic data (such as gender and age) and past medical history (such as hypertension, diabetes, and smoking history) were collected. The levels of serum low-density lipoprotein cholesterol (LDL-C), hypersensitivity C reactive protein (hs-CRP), glycosylated hemoglobin (HbAlc), homocysteine (HCY), uric acid (UA), fibrinogen (Fib), and Lp-PLA2, etc. were measured. Logistic regression analysis was used to assess the related factors of VBD and ischemic stroke secondary to VBD.

RESULTS

Logistic multivariate regression analysis showed that only age and the level of serum Lp-PLA2 were significantly higher in group B than those in group A (P < 0.012, P < 0.001, respectively), however, only the level of serum Lp-PLA2 was significantly higher in group C than those in group B (P < 0.001).

CONCLUSIONS

The serum marker Lp-PLA2 is an independent risk factor for the occurrence of VBD and the progression of VBD to posterior circulation ischemic stroke. Whether intervening on atherosclerosis could prevent the occurrence and development of VBD needs to be further studied.

Ultrasound Findings Disclose the Mutual Impact of Vertebrobasilar Dolichoectasia and Vertebral Artery Hypoplasia

OBJECTIVES

Vertebrobasilar dolichoectasia (VBD) and vertebral artery hypoplasia (VAH) are known predisposing factors of posterior circulation stokes. These vascular conditions have unique hemodynamic patterns in neuroimaging studies; however, they have been presented as a single entity in some reports. The aim of this retrospective study was to clarify the relationship between these conditions with regard to ultrasound (US) findings.

METHODS

A total of 465 patients with strokes were recruited. Brain magnetic resonance imaging of vertebrobasilar arteries and differences in extracranial side-to-side vertebral artery (VA) flow were recorded by US and compared in groups.

RESULTS

The mean age of the 465 patients ± SD was 67.23 ± 12.13 years; 296 were men. The prevalence of VBD was 13.5% (n = 63), and 10.8% (n = 50) of the patients had coexisting VAH and VBD. These patients also had the highest prevalence of posterior circulation strokes (58% [n = 29]). A cutoff value of 55.65 mL/min and a ratio discrepancy of 5.28 (group median) for the side-to-side extracranial VA flow volume as detected by conventional US were also observed in the patients with both VAH and VBD.

CONCLUSIONS

Our study revealed a higher prevalence of posterior circulation strokes in the patients with both VBD and VAH. Chronic asymmetric hemodynamic shear force in extracranial VAs leading to deformity of the vertebrobasilar system may explain our observations. Accordingly, the blood flow volume and the ratio difference could potentially be used to detect patients at risk of VBD and reduce stroke risk factors.

The safety and efficacy of using large woven stents to treat vertebrobasilar dolichoectasia

OBJECTIVES

To characterize the safety and efficacy of large woven stents in the treatment of vertebrobasilar dolichoectasia (VBD).

METHODS

We retrospectively reviewed 19 consecutive patients with VBD treated with large woven intracranial stent (Leo stents) between January 2016 and December 2018. The clinical symptoms and angiograms of all the patients were recorded.

RESULTS

The patients were treated with 1-3 large Leo stents (5.5 mm x 75 mm, 5.5 mm x 50 mm, or 4.5 mm x 40 mm), with or without coiling. They had follow-up angiography and MRI between 3 months and 1 year. Digital subtraction angiography showed 16 patients with complete reconstruction of the target vessels, one patient with almost complete reconstruction, and two patients with partial reconstruction. All patients had symptomatic improvement shortly after treatment, but two patients developed recurrent dysphagia at 8 and 18 months, respectively.

CONCLUSIONS

Deployment of woven stents with or without supportive coiling may offer symptom relief and reconstruction in patients with VBD.

Outcomes in Symptomatic Patients With Vertebrobasilar Dolichoectasia Following Endovascular Treatment

Objective: To evaluate whether the presenting symptoms of VBD predict outcomes following endovascular treatment.

Methods: We retrospectively reviewed our institutional clinical database and identified 22 patients (all men; mean age: 52.6 years, range: 11–73 years) with a diagnosis of VBD, who underwent endovascular treatment from January 2010 to December 2017.

Results: After analyzing the clinical and imaging data, we evaluated data for 22 symptomatic patients with VBD. At the time of VBD diagnosis, 13 patients (59%) had compressive symptoms, four (18%) had hemorrhagic symptoms, and five (23%) had ischemic symptoms. Nine of the 22 patients (41%), who presented with hemorrhagic and ischemic symptoms, achieved a satisfactory clinical and/or digital subtraction angiography imaging outcome after endovascular treatment. However, of the 13 patients who presented with compressive symptoms, seven (54%, 7/13) died from severe brainstem compression during follow-up; furthermore, magnetic resonance imaging showed worsening of the mass effect in eight patients with compressive symptoms (62%, 8/13).

Conclusions: VBD is considered a challenging lesion without an ideal treatment modality. Endovascular treatment of VBD in patients presenting with compressive symptoms at diagnosis may not be beneficial. However, long-term outcomes following endovascular treatment may be acceptable in patients with non-compressive symptoms at diagnosis compared with those with compressive symptoms.

Fatal subarachnoid hemorrhage following ischemia in vertebrobasilar dolichoectasia

Vertebrobasilar dolichoectasia (VBD) is a chronic disorder with various cerebrovascular and compressive manifestations, involving subarachnoid hemorrhage (SAH). Occurrence of SAH shortly after worsening of clinical VBD symptoms has occasionally been reported. The goal of the study was to examine this association, in particular its pathophysiology, clinical precursor signs, time course, and outcome.To this end, in a retrospective multicenter study, we analyzed 20 patients with VBD and SAH in regard to preceding clinical symptoms, presence of vertebrobasilar thrombosis and ischemia, outcome and neuropathological correlates.Median age of the 7 female and 13 male patients was 70 years (interquartile range [IQR] 18.3 years). Fourteen patients (70%) presented with new or acutely worsening posterior fossa signs at a median of 3 days prior to SAH (IQR 2, range 0.5-14). A thrombus within the VBD was detected in 12 patients (60%). Thrombus formation was associated with clinical deterioration (χ = 4.38, P = 0.04) and ponto-cerebellar ischemia (χ = 8.09, P = 0.005). During follow-up after SAH, 13 patients (65%) died, after a median survival time of 24 hours (IQR 66.2, range 2-264 hours), with a significant association between proven ponto-cerebellar ischemia and case fatality (χ = 6.24, P = 0.01).The data establish an association between clinical deterioration in patients with VBD, vertebrobasilar ischemia, and subsequent SAH. Antithrombotic treatment after deterioration appears controversial and SAH outcome is frequently fatal. Our data also indicate a short window of 3 days that may allow for evaluating interventional treatment, preferably within randomized trials.

Multimodality Imaging of Vertebrobasilar Dolichoectasia: Clinical Presentations and Imaging Spectrum

Vertebrobasilar dolichoectasia (VBD) is characterized by ectasia, elongation, and tortuosity of the vertebrobasilar arteries, with a high degree of variability in clinical presentation. The disease origin is believed to involve degeneration of the internal elastic lamina, thinning of the media secondary to reticular fiber deficiency, and smooth muscle atrophy. The prevalence of VBD is variable, ranging from 0.05% to 18%. Most patients with VBD are asymptomatic and their VBD is detected incidentally; however, it is important to recognize that the presence of symptoms, which can lead to clinically significant morbidity and sometimes mortality, may influence clinical management. The most important clinical presentations of VBD are vascular events, such as ischemic stroke and catastrophic intracranial hemorrhage, or progressive compressive symptoms related to compression of adjacent structures, including the cranial nerves, brainstem, or third ventricle, causing hydrocephalus. The imaging diagnostic criteria for computed tomography and magnetic resonance (MR) imaging include three quantitative measures of basilar artery morphology: laterality score, height of bifurcation, and basilar artery diameter. The authors review the relevant anatomy and disease origin of VBD; pertinent imaging findings, including intraluminal thrombus and relation to the cranial nerves; and imaging pitfalls, such as the hyperintense vessel sign on MR images and artifacts related to slow flow in the dolichoectatic vessel. In addition, clinical manifestations, the role of radiology in diagnosis and management of this condition, and available management options are reviewed. (©)RSNA, 2016.

Morphological Characteristics of the Vertebrobasilar Arterial System Are Associated with Vertebrobasilar Dolichoectasia

Background

Vertebrobasilar dolichoectasia (VBD) is characterized by abnormal dilation, distortion, and extension of the vertebral artery (VA) and basilar artery (BA). This study investigated whether BA and VA morphological characteristics were factors predicting VBD.

Material/Methods

Individuals aged ≥18 years undergoing contrast-enhanced magnetic resonance angiography (CE-MRA) of the head/neck were enrolled in 2012 at Changhai Hospital, Shanghai. Data concerning cardiovascular risk factors were recorded. Bilateral VA diameter and lateral displacement, BA diameter and lateral displacement, VA confluence displacement, and dominant VA (DVA) presence/absence were determined from CE-MRA. VBD was diagnosed using established criteria. DVA and no-DVA groups were compared. Logistic regression analysis was used to identify variables independently associated with VBD.

Results

Our study included 1153 individuals, of which 614 (53.3%) had DVA. The DVA group had higher mean age, hypertension prevalence (44.6% vs. 37.5%), and VBD prevalence (8.1% vs. 4.5%), and lower smoking prevalence (24.3% vs. 30.6%), than no-DVA patients. Univariate analysis revealed that age, female sex, hypertension, hyperlipidemia, smoking, alcohol consumption, and DVA presence were associated with VBD occurrence. Multivariate analysis showed that age and presence of a DVA were independently associated with VBD.

Conclusions

Age and presence of DVA are independently associated with VBD.

Research progress on vertebrobasilar dolichoectasia

Vertebrobasilar dolichoectasia (VBD) is a rare disease characterized by significant expansion, elongation, and tortuosity of the vertebrobasilar arteries. Current data regarding VBD are very limited. Here we systematically review VBD incidence, etiology, characteristics, clinical manifestations, treatment strategies, and prognosis. The exact incidence rate of VBD remains unclear, but is estimated to be 1.3% of the population. The occurrence of VBD is thought to be due to the cooperation of multiple factors, including congenital factors, infections and immune status, and degenerative diseases. The VBD clinical manifestations are complex with ischemic stroke as the most common, followed by progressive compression of cranial nerves and the brain stem, cerebral hemorrhage, and hydrocephalus. Treatment of VBD remains difficult. Currently, there are no precise and effective treatments, and available treatments mainly target the complications of VBD. With the development of stent technology, however, it may become an effective treatment for VBD.

A comparison of CT/CT angiography and MRI/MR angiography for imaging of vertebrobasilar dolichoectasia

PURPOSE

Vertebrobasilar dolichoectasia (VBD) is a rare dilatative arteriopathy predominantly affecting the basilar artery (BA) and vertebral arteries. Until today, the value of computed tomography (CT)/CT angiography (CTA) compared with magnetic resonance imaging (MRI)/time-of-flight MR angiography (TOF-MRA) has not been studied systematically.

METHODS

We (1) compare CTA and TOF-MRA according to the established criteria (diameter at the mid-pons level, height, and lateral position), (2) explore the value of further CTA- and TOF-MRA-derived measures (maximum transverse diameter and length), as well as (3) explore the value of further non-contrast-enhanced MRI sequences such as T1, fluid-attenuated inversion recovery, and T2* for a detailed characterization of VBD in a series of 18 patients.

RESULTS

Comparison of CTA and TOF-MRA revealed very good consistency of the measured diameter (Pearson's r = 0.994, p = 0.01) and the noted height of the BA (Kendall's tau = 1.0, p = 0.001). The same held true for the maximum transverse diameter (Pearson's r = 0.988, p = 0.01) and length of the BA (Pearson's r = 0.986, p = 0.01). In contrast to this, there was a lower agreement concerning the lateral position (Kendall's tau = 0.866, p = 0.01). In comparison with the diameter at the mid-pons level, the maximum transverse diameter was significantly larger (p = 0.002). Luminal thrombus was detected equally well by CTA and TOF-MRA. CT was useful to detect small circumscribed calcifications, whereas MRI was advantageous to demonstrate perifocal brainstem edema.

CONCLUSIONS

We could demonstrate a substantial comparability of CT/CTA and MRI/TOF-MRA in the diagnosis of VBD. The maximum transverse diameter and length may be useful when an endovascular treatment is considered. Taking into account the different informative value of both techniques, it may be worth to perform both imaging procedures.