Intracranial Vertebral Artery Dissection Research Articles

Behavior of Extracranial-to-Intracranial Extended Arterial Dissections of the Vertebral Artery.

Vertebral artery dissections (VADs) may extend from the extracranial to the intracranial vasculature (e+iVAD). We evaluated how the characteristics of e+iVAD differed from those of intracranial VAD (iVAD). From 2002 to 2019, among consecutive patients with cervicocephalic dissection, those with iVAD and e+iVAD were included, and their clinical characteristics were compared. In patients with unruptured dissections, a composite clinical outcome of subsequent ischemic events, subsequent hemorrhagic stroke, or mortality was evaluated. High-resolution magnetic resonance images were analyzed to evaluate intracranial remodeling index. Among 347 patients, 51 (14.7%) had e+iVAD and 296 (85.3%) had iVAD. The hemorrhagic presentation occurred solely in iVAD (0.0% versus 19.3%), whereas e+iVAD exhibited higher ischemic presentation (84.3% versus 27.4%; P<0.001). e+iVAD predominantly presented steno-occlusive morphology (88.2% versus 27.7%) compared with dilatation patterns (11.8% versus 72.3%; P<0.001) of iVAD. The ischemic presentation was significantly associated with e+iVAD (iVAD as a reference; adjusted odds ratio, 3.97 [95% CI, 1.67-9.45]; P=0.002]). Patients with unruptured VAD showed no differences in the rate of composite clinical outcome between the groups (log-rank, P=0.996). e+iVAD had a lower intracranial remodeling index (1.4±0.3 versus 1.6±0.4; P<0.032) and a shorter distance from dural entry to the maximal dissecting segment (6.9±8.4 versus 15.7±7.4; P<0.001). e+iVAD is associated with lower rates of hemorrhages and higher rates of ischemia than iVAD at the time of admission. This may be explained by a lower intracranial remodeling index and less deep intrusion of the dissecting segment into the intracranial space.

A Comparative Study of the Etiology of Intracranial Vertebral Artery Dissection and Carotid Artery Dissection.

Both extrinsic (trauma or violent movement) and intrinsic (structural abnormality, atherosclerosis, or hemodynamic instability) factors may result in arterial dissection. The role of these factors in the origin or progression of dissection remains unclear. This study aimed to characterize the clinical features, radiologic features, and outcomes of intracranial vertebral artery dissection compared with carotid artery dissection and to determine the major causative factors. Consecutive patients with craniocervical dissection (n=127) were retrospectively analyzed. Patients with intracranial vertebral artery dissection (n=77) and those with carotid artery dissection (n=35) were compared with respect to patient age, sex, cerebrovascular risk factors, laboratory indices, and radiologic features. Intracranial vertebral artery dissection was the most common craniocervical arterial dissection in our cohort (n=77, 60.6%). Body mass index in the intracranial vertebral artery dissection group was significantly greater than that in carotid artery dissection group. Clinical manifestations of intracranial vertebral artery dissection included ischemic stroke (37.7%), dizziness or vertigo (39.0%), and headache or neck pain (44.2%). Two patients had a definite history of trauma. The frontal and lateral tortuosity ratios of the vertebral basilar artery were significantly greater while the vertex angle was smaller in the intracranial vertebral artery dissection group compared with carotid artery dissection group. A positive correlation between the tortuosity ratios and subarachnoid hemorrhage and a significant inverse correlation between the tortuosity ratios and lipid parameters (high-density lipoprotein; apolipoprotein A1) were identified. Intrinsic causes may play a more important role in the development of intracranial vertebral artery dissection than carotid artery dissection.

Acute hemicranial pain accompanied with a pearl and string type dissection of intracranial vertebral artery: Consideration for the time when to finish the medical observation.

The International Classification of Headache Disorder (ICHD) clearly guides the suspicion of intracranial vertebral artery dissection (ICVAD) in headache patients, but guidelines on how observational or imaging studies should be performed to detect dangerous progression early are unclear. Fifty-six cases with pearl and string type intracranial vertebral artery dissection were divided into 3 groups: 39 in the headache group, 6 in the infarction group, and 11 in the hemorrhagic group. Clinical and angiographic data were analyzed and compared. Most headaches resolved within 2 weeks and did not exceed 8 weeks. Of the 33 patients (84.6%) who underwent continuous follow-up imaging, 18 (54.5%) returned to normal, but 3 (9%) had deteriorated. All the patients survived without subsequent bleeding or infarction. Image changes started before 3rd month and ended after 6 to 7 months. In acute ICVADs, image changes occur at the same time as the headache resolves and continue for several months after the headache has subsided. Since the dissection is likely to worsen even after the headache disappears, the image changes continue over several months, and prediction of rupture of unruptured ICVAD is unpredictable, it is desirable to conduct continuous imaging studies regularly after the initiation of dissection until stabilization is confirmed.

Diagnostic accuracy of MR vessel wall imaging at 2 weeks to predict morphological healing of vertebral artery dissection

ObjectivesThe spontaneous healing of non-hemorrhagic intracranial vertebral artery dissection (VAD) may be associated with the stabilization of intramural hematoma (IMH). We previously suggested that the signal intensity of IMH increases until approximately 2 weeks in VAD with spontaneous healing. We herein investigated the diagnostic accuracy of the signal intensity of IMH at 2 weeks to predict the spontaneous healing of VAD. MethodsFrom April 2017 to April 2021, we prospectively investigated patients with non-hemorrhagic VAD who underwent vessel wall imaging (VWI). Morphological healing of VAD was evaluated by MR angiography three months after its onset. The relative signal intensity (RSI) of IMH against the posterior cervical muscle on VWI was calculated. Univariate and multivariate analyses were performed on factors associated with the spontaneous healing of VAD among patient baseline data, vascular morphology at the diagnosis, and RSI parameters. ResultsForty-eight patients (23 men and 25 women; mean age: 51 years, range: 34-73 years) with 50 non-hemorrhagic VAD were included in the present study. Spontaneous healing was observed in 28 VAD (56%). RSI two weeks after the onset of VAD (RSI2w) and morphological feature such as the string sign were associated with spontaneous healing, respectively. The multivariate logistic regression analysis identified RSI2w as an independent predictive factor of spontaneous healing (OR: 7.3; 95% CI, 1.9-28, p = 0.004). The cut-off value for RSI2w to predict spontaneous healing was 1.22 (AUC = 0.90, sensitivity: 91%, specificity: 82%). ConclusionRSI2w predicted the spontaneous healing of non-hemorrhagic VAD 3 months after its onset.

Detection of cerebral aneurysm and intracranial vertebral dissection using non-enhanced magnetic resonance imaging in emergency setting: Emphasis on magnitude image of susceptibility-weighted image.

To evaluate image features and diagnostic performance of susceptibility-weighted image (SWI) in detection of intracranial vertebral artery dissection (VAD) and unruptured intracranial aneurysm (UIA). From January 2015 to December 2021, symptomatic patients who underwent 3.0 T MR SWI were recruited. For study group, transfemoral cerebral angiography-proven lesions were included, while 1:1 matched control group with MR angiography were included. Image features of SWI were evaluated. Diagnostic performance and interobserver agreements were calculated for detecting VAD with stenosis and UIA greater than 7 mm. Total of 110 patients (mean age: 60.92 years, female: 60/110) were included. In the study group (N = 55), 21 patients (38.2%) had VAD, while 34 patients (61.8%) had UIA. For SWI-detectable VAD, larger parent artery (PA)-dilatation ratio was observed (1.36 vs. 1.84, p = 0.034). For SWI-detectable UIA, larger PA-dome ratio (1.32 vs. 1.90, p = 0.020) and larger PA-height ratio (1.25 vs. 1.77, p = 0.005) were observed. The diagnostic performance and kappa values for VAD with stenosis were as follow: sensitivity: 91.7 (95% CI: 61.5-99.8); specificity: 93.9 (95% CI: 87.2-97.7); к: 0.80. The diagnostic performance for UIA larger than 7 mm were as follow: sensitivity: 87.5 (95% CI: 47.4-99.7); specificity: 95.1 (95% CI: 88.9-98.4); к: 0.73. SWI-detectable lesions were VAD with larger PA-dilatation ratio, and UIA with larger PA-dome ratio, and PA-height ratio. SWI was able to accurately detect VAD with stenosis and UIA larger than 7 mm with substantial interobserver agreements.

Diagnostic Performance of High-Resolution Vessel Wall Magnetic Resonance Imaging and Digital Subtraction Angiography in Intracranial Vertebral Artery Dissection.

Purpose: Intracranial vertebral artery dissection (VAD) is being increasingly recognized as a leading cause of Wallenberg syndrome and subarachnoid hemorrhage. Conventional angiography is considered the standard diagnostic modality, but the diagnosis of VAD remains challenging. This study aimed to compare the diagnostic performance of high-resolution vessel wall imaging (HR-VWI) with digital subtraction angiography (DSA) for intracranial VAD. Materials and methods: Twenty-four patients with 27 VADs, who underwent both HR-VWI and DSA within 2 weeks, were consecutively enrolled in the study from March 2016 to September 2020. HR-VWI and DSA were performed to diagnose VAD and to categorize its angiographic features as either definite dissection or suspicious dissection. Features of HR-VWI were used to evaluate direct arterial wall imaging. The reference standard was set from the clinicoradiologic diagnosis. Two independent raters evaluated the angiographic features, dissection signs, and interrater agreement. Each subject was also dichotomized into two groups (suspicious or definite VAD) in each modality, and diagnosis from HR-VWI and DSA was compared with the final diagnosis by consensus. Results: HR-VWI had higher agreement (90.6% vs. 53.1%) with the final diagnosis and better interrater reliability (kappa value (κ) = 0.91; 95% confidence interval (CI) = 0.64–1.00) compared with DSA (κ = 0.58; 95% CI = 0.35–1.00). HR-VWI provided a more detailed identification of dissection signs (77.7% vs. 22.2%) and better reliability (κ = 0.88; 95% CI = 0.58–1.00 vs. κ = 0.75; 95% CI = 0.36–1.00), compared to DSA. HR-VWI was comparable to DSA for the depiction of angiographic features for VAD. Conclusions: HR-VWI may be useful to evaluate VAD, with better diagnostic confidence compared to DSA.

Recurrent attacks of transient global amnesia with intracranial vertebral artery dissection: Case report

Whether Transient global amnesia (TGA) is related to ischemic pathogenesis remains unclear. The recurrence of TGA is rare. We report a rare case of recurrent attacks of TGA with intracranial vertebral artery dissection in young men without other triggers and any associated factor. A 39-year-old man was hospitalized for amnesia. Diffusion-weighted imaging (DWI) revealed a tiny focus of high-intensity signals in the left. High-resolution MRI showed the dissecting aneurysm of the V4 portion of the right vertebral artery. Two years later, the patient experienced sudden memory loss again. On DWI, a new punctate restricted diffusion lesion was observed in the left hippocampus. Considering the recurrence in young men with no other triggers, this case raises the hypothesis that a pure TGA in a young patient could potentially be a vertebrobasilar TIA. Therefore, when a patient presents with TGA, without any associated factors, it is important to investigate and exclude sinister causes of global amnesia and we recommend that a vascular examination be conducted.

Delayed Diagnosis of Intracranial Vertebral Artery Dissection Mimics Primary Thunderclap Headache

Key Words: Vertebral artery dissection, Headache disorders, Secondary, Magnetic resonance angiography

Monitoring Intramural Hematoma on Vessel Wall Imaging to Evaluate the Healing of Intracranial Vertebral Artery Dissection

ObjectiveUnruptured intracranial vertebral artery dissection (VAD) generally heals spontaneously. A chronological evaluation of intramural hematoma (IMH) using T1-weighted vessel wall imaging (VWI) may provide a more detailed understanding of the pathophysiology of VAD. We herein investigated the relationship between chronological signal changes in IMH on VWI and the spontaneous healing of VAD. Materials and MethodsWe retrospectively investigated 26 patients with 27 unruptured VADs who underwent magnetic resonance (MR) imaging more than three times during the follow-up period. Morphological changes were evaluated using MR angiography (MRA). The relative signal intensity (RSI) of IMH against the posterior cervical muscle on T1-weighted VWI was calculated. The ratio of chronological RSI changes was defined as follows: maximum RSI/minimum RSI (RSI max/min). Based on the median value of RSI max/min, 27 VADs were divided into VADs with and without chronological RSI changes. Statistical analyses were performed to compare clinical and radiological findings between the two groups. ResultsSpontaneous healing occurred in 17 out of 27 VADs (63%). The median value of RSI max/min was 1.48. The RSI of VADs with chronological RSI changes (RSI max/min ≥ 1.48) increased until three weeks after their onset and decreased over time, while that of VADs without chronological RSI changes (RSI max/min < 1.48) showed no change. The frequency of healing was significantly higher in VADs with than without chronological RSI changes (100% vs 23%, p < 0.0001). ConclusionsChronological signal changes in IMH on T1-weighted VWI have potential as a diagnostic imaging marker of the spontaneous healing of VAD.

Factors Predictive of Enlargement of Dissecting Aneurysms in the Vertebral Artery

To elucidate the incidence rate of enlargement of vertebral artery dissecting aneurysms (VADAs) during the acute phase and factors associated with enlargement. Of 115 patients with unilateral intracranial vertebral artery dissection who did not experience subarachnoid hemorrhage, 64 with the pearl sign of vertebral artery dissection (VADA without stenosis) participated in the study. We performed initial magnetic resonance imaging to diagnose VADA and subsequent magnetic resonance imaging to evaluate VADA enlargement. The presence of a hyperintense intramural signal was confirmed using T1-weighted three-dimensional turbo spin-echo imaging. Enlargement of VADAs between the initial and subsequent examinations was evaluated via magnetic resonance angiography and defined as the end point. We studied the rate of VADA enlargement using Kaplan-Meier curve analysis. After independent variables were determined, the Cox proportional hazards model was applied in multivariable analysis to identify the factors significantly associated with VADA enlargement. Of 64 patients (mean age, 55.7 ± 13.0 years; 44 men and 20 women), 15 exhibited VADA enlargement. Kaplan-Meier curve analysis indicated that 24.8% of VADA enlargements were detected 30 days after initial magnetic resonance imaging. The Cox proportional hazards model revealed that young age (hazard ratio 0.953, P= 0.043) and the presence of hyperintense intramural signal (hazard ratio 2.841, P= 0.033) were significantly associated with VADA enlargement. VADAs enlarged by approximately 25% until day 30 after the initial examination. Younger age and the presence of hyperintense intramural signal were significantly associated with VADA enlargement.

Nystagmus in Intracranial Vertebral Artery Dissection Caused by Golf Swing

Nystagmus in Intracranial Vertebral Artery Dissection Caused by Golf Swing

Endovascular Treatment of Intracranial Vertebral Artery Dissection.

Intracranial vertebral artery dissection (VAD) is the most common arterial dissection in intracranial arteries. Some types of VAD can heal spontaneously after reconstitution of the vessel lumen with excellent prognosis, whereas others can progress to stroke that needs treatment. Recently, endovascular treatment (EVT) has emerged and is suggested as a treatment option for VADs due to perceived low rates of procedure-related morbidity with good efficacy. In the last decade, we have accumulated our strategies to treat those VADs. Here, we try to share our experiences about VADs, including indications and methods of treatment of VADs using EVT. We perform EVT for ruptured VADs presenting with SAH and some of unruptured VADs such as VAD with recurrent or progressive ischemia, dissecting aneurysm larger than 7 mm or with mass effect, early ugly change of VADs in shape and size during follow-up period, involving the basilar artery (BA) and bilateral VADs. We present how we have done in our real practice for the last decade for treating VADs by EVT rather than reviewing and organizing so-far-published literature. We tended to occlude the rupture point by vertebral artery (VA) occlusion in non-dominant VA or stent-assisted coiling in dominant VA for ruptured VADs. We tended to reconstruct original hemodynamics using various stents for unruptured VADs. To decide what to treat and how to treat are very complicated for VADs. However, we believe that EVT is the current mainstay for treating VADs. Each technique of EVT should be determined on a case-by-case basis at the discretion of endovascular neurosurgeons and/or interventional neuroradiologists according to presenting symptoms, hemodynamic status, including sufficiency of the collateral supply and anatomic features of the vertebrobasilar artery as well as the posterior inferior cerebellar artery, anterior spinal artery, and medullary perforators.

Endovascular Management of Intracranial Vertebral Artery Dissection: Technical Nuances for the Preservation of Posterior Inferior Cerebellar Artery and Basilar Artery.

The treatment of intracranial vertebral artery dissection (VAD) can be challenging. To evaluate the clinical presentation, endovascular treatment techniques, and prognostic outcome of patients diagnosed with intracranial VAD at our institution. A retrospective analysis of 35 patients who were diagnosed with VAD at our institution over 17-yr period (2001-2017) is presented. A total of 27 patients with a total of 30 affected arteries underwent endovascular treatment, and their outcome was evaluated. Of the 35 total patients with VAD, 15 presented with headache, 12 with focal neurological deficits, 2 with neck pain, 2 with dizziness, 1 with syncope, and 3 after trauma. Of the 30 dissected arteries, 18 were treated with deconstruction and 12 were treated with stent reconstruction. Treatment method was determined by the dominance of the affected artery and location relative to the ipsilateral posterior inferior cerebellar artery (PICA) and the basilar artery. Deconstructive techniques were utilized in all cases of hypoplastic artery dissection and the majority of codominant artery dissections, whereas reconstruction was performed on the majority of dominant artery dissections. Rupture did not impact treatment technique. Four patients demonstrated post-treatment infarcts, and another 1 patient died because of intraparenchymal bleed. The remaining 22 patients demonstrated favorable clinical outcome. None of the patients developed recanalization or needed retreatment till the last follow-up. This study suggests that endovascular treatment of intracranial VAD with deconstruction or stent reconstruction based on the patients anatomy, particularly vessel dominance and location with respect to PICA, is feasible and effective though the revascularization procedures still has its role in selected cases.

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.

Abstract TP84: Prognostic Factor of Intracranial Vertebral Artery Dissection: High Resolution Vessel Wall Magnetic Resonance Imaging Study

Background: Vertebral artery dissection (VAD) is well recognized cause of stroke in young and middle aged individuals. But, prognostic factor of posterior circulation ischemic stroke or transient ischemic attack (TIA) caused by intracranial VAD has been rarely discussed. Our aim was to evaluate the predictors of poor outcomes in posterior circulation ischemic stroke caused by intracranial VAD. Methods: We retrospectively reviewed patients with posterior circulation ischemic stroke or TIA caused by intracranial VAD using high-resolution vessel wall MRI who were recruited from Samsung Medical Center Stroke Registry (between January 1, 2011 and April 30, 2019). Poor outcomes were defined as a 3-months modified Rankin scale (mRS) score ≥ 2. Results: We registered 96 patients (74 males; mean age, 58.9±14.2 years) with acute posterior circulation ischemic stroke or TIA caused by intracranial VAD. Trauma history associated with VAD was presented in 23 (24%) of patients. Headache and neck pain around neurological symptom onset were presented in 41 (42.7%) and 19 (19.8%) of patients, respectively. Dissecting aneurysm, bilateral vertebral artery involvement, basilar artery involvement and wall hematoma with dissection were presented in 26 (27.1%), 26 (27.1%), 12 (12.5%) and 66 (68.8%) of patients, respectively. Of the 96 VADs, 26 (27.1%) presented with focal stenosis, 21 (21.9%) with multifocal stenosis, and 57 (59.4%) with occlusion. Lateral medulla involvement and multiple territory involvement were presented in 35 (36.5%) and 31 (32.3%) of patients. Recurrence rate of ischemic stroke or TIA within 90 days of symptom onset was 6.25%. Twenty-nine patients (30.2%) had poor outcomes at 3 months. Lateral medulla involvement was an independent predictor for poor outcome (odds ratio=3.293, 95% confidence interval=1.301-8.333, p=0.012). Conclusion: Posterior circulation ischemic stroke or TIA caused by intracranial VAD is associated with relatively benign clinical course. But the presence of lateral medulla involvement is independent predictor for poor outcome. Patients presenting lateral medullary infarction caused by intracranial VAD should be monitored closely.

Subarachnoid haemorrhage due to intracranial vertebral artery dissection presenting with atypical cauda equina syndrome features: case report

BackgroundFailing to recognise the signs and symptoms of subarachnoid haemorrhage (SAH) causes diagnostic delay and may result in poorer outcomes. We report a rare case of SAH secondary to a vertebral artery dissection (VAD) that initially presented with cauda equina-like features, followed by symptoms more typical of SAH.Case presentationA 55-year-old man developed severe lower back pain after sudden movement. Over the next 5 days he developed paraesthesiaes in the feet, progressing to the torso gradually, and reported constipation and reduced sensation when passing urine. On day six he developed left facial palsy, and later gradual-onset headache and intermittent confusion.Magnetic resonance imaging of the brain showed diffuse subarachnoid FLAIR hyperintensity, concerning for blood, including a focus of cortical/subcortical high signal in the left superior parietal lobule, which was confirmed by computed tomography. Digital subtraction angiography demonstrated a left VAD with a fusiform aneurysm.ConclusionWe present a very rare case of intracranial VAD with SAH initially presenting with spinal symptoms. The majority of subsequent clinical features were consistent with a parietal focus of cortical subarachnoid blood, as observed on neuroimaging.

Detection of Stenosis Progression in Intracranial Vertebral Artery Dissection Using Carotid Ultrasonography

Background: The purpose of this study was to assess whether carotid ultrasonography indices detect arterial stenosis progression in patients with vertebral artery (VA) dissection. Methods: This was a retrospective, single-center, observational study that enrolled patients with intracranial VA dissection who were admitted from January 2011 to June 2017. Magnetic resonance angiography (MRA) was done on admission and followed up at a median 20 days after onset (interquartile range [IQR] 9-58 days), and ultrasonography was performed at a median of 22 (interquartile range 7-56) days. Peak systolic velocity (PSV), end-diastolic velocity (EDV), mean velocity (MV), and pulsatility index (PI) were measured by ultrasonography, and the ratio of each follow-up value to the baseline (follow-up/baseline) value was calculated. Two stroke neurologists categorized into 3 groups by morphological changes of the dissected vessel: patients with stenosis progression (progression group: P-group); those with no remarkable change or dilatation improved (stable group: S-group); and those with stenosis regression or dilatation enlargement (enlargement group: E-group). Ultrasonography indices were compared among the groups. Results: Of the 42 patients who were enrolled to this study, 39 patients underwent ultrasonography and MRA on both admission and follow-up. The PI ratio was significantly higher in the P-group than in the S-group (1.96 ± .80 versus .98 ± .44, P = .02) and in the E-group (versus .65 ± .35, P < .01). There were no significant differences in the PSV ratio, EDV ratio, and MV ratio. Conclusions: In patients with VA dissection, the PI ratio on ultrasonography is a promising index to detect stenosis progression.

Reconstructive endovascular treatment of the V4 segment of a vertebral artery dissecting aneurysm with the Willis covered stent: A retrospective study.

Preliminary studies suggest that Willis covered stents may be suitable for the treatment of aneurysms of the internal carotid artery (ICA), but their efficacy and safety in vertebral artery (VA) dissecting aneurysms need further investigation. Consecutive patients who underwent placement of a Willis covered stent for treatment of an aneurysm of the V4 segment of the VA between September 2015 and December 2017 at our institution were retrospectively reviewed. The efficacy, complications, angiographic and clinical follow-up results were collected and analyzed. Sixteen covered stents were successfully implanted into the VA in 12 patients with 12 dissecting aneurysms. The technical success rate of stenting placement was 100%. Complete occlusion was achieved in 11 patients immediately after stent placement, with transient endoleak in one aneurysm. Angiographic follow-up (9.9 ± 4.0 months, mean±SD) was performed in nine patients and demonstrated complete stabilization of the obliterated aneurysm. Clinical follow-up (20.1 ± 9.6 months, mean±SD) demonstrated full recovery in 11 patients, and one patient suffered from acute myocardial infarction. Reconstruction using a Willis covered stent is an efficient, safe and attractive alternative for the definitive treatment of intracranial VA dissecting aneurysms; longer follow-up and expanded clinical trials are needed for further validation of this technique.

Genetic analysis of ring finger protein 213 (RNF213) c.14576G>A polymorphism in patients with vertebral artery dissection: a comparative study with moyamoya disease

ABSTRACTBackground: Intracranial vertebral artery dissection (VAD) and moyamoya disease (MMD) are rare cerebrovascular diseases, both of which have an ethnic predominance in the East Asian population. Disruption of the internal elastic lamina and subsequent rupture of the medial layer result in intracranial VAD. MMD is a chronic occlusive cerebrovascular disease of unknown etiology, in which the medial layer and internal elastic lamina of the intracranial arteries are significantly compromised. Recent genetic studies found ring finger protein 213 (RNF213) to be an important susceptibility gene for MMD in East Asian patients, but the association between VAD and RNF213 has not been investigated. .Methods: We investigated polymorphism of the RNF213 gene (c.14576G>A) in genomic DNA of 24 patients with intracranial VAD in comparison with 58 patients with definitive MMD and 48 healthy controls.Results: Although RNF213 gene polymorphism (c.14576G>A) was evident in 69% of the MMD patients (40/58), none of the patients with intracranial VAD had this characteristic polymorphism (0/24, p < 0.001). The incidence of RNF213 c.14576G>A polymorphism was 4.2% in healthy controls (2/48). After adjustment by age and sex, the incidence of RNF213 c.14576G>A was significantly lower in intracranial VAD patients (p = 0.021) than that in MMD patients.Conclusions: In contrast to MMD patients, the prevalence of RNF213 c.14576G>A polymorphism was significantly lower in patients with intracranial VAD. The RNF213 gene polymorphism may preferentially affect the cerebrovascular lesion in the anterior circulation, which is originated from the primitive internal carotid arteries. The genetic background underlying intracranial VAD should be elucidated in future studies.Abbreviations: VAD: vertebral artery dissection; MMD: moyamoya disease; RNF213: ring finger protein 213; CAD: carotid artery dissection

Conservative Management of Unruptured Spontaneous Intracranial Vertebral Artery Dissection

The present study investigated the clinical and morphological characteristics of the vertebrobasilar artery associated with vascular healing in patients with unruptured spontaneous intracranial vertebral artery (VA) dissection (VAD). We retrospectively reviewed the data from 69 consecutive patients with a diagnosis of unruptured VAD who were treated conservatively for ≥21 days from November 2003 to February 2018 at our institute. Univariate and multivariate analyses were performed to evaluate the clinical characteristics and morphological findings of VAD. Of the 69 patients, vascular normalization of VAD was observed in 26, including a significantly greater proportion of women and nonsmokers (P= 0.04 and P= 0.034, respectively). Patients with normalization of VAD had a significantly lower proportion of posteroinferior cerebellar artery involvement and a smaller vertebral-union-basilar angle of the nondissecting VA, smaller vertebral-union-vertebral angle, distal dissection from the VA union, and less basilar artery bending. Luminal irregularity/steno-occlusion of the VAD on the initial images exhibited vascular resolution/normalization in 25 patients (67.6%) on subsequent images. The morphology of VAD in the dominant or codominant VAs included fusiform/aneurysmal dilatation in 25 patients (78.1%). The morphology in the nondominant VA included luminal irregularity/steno-occlusion in 23 patients (62.2%). Spontaneous vascular normalization of unruptured spontaneous intracranial VAD might be associated with female sex, nonsmoking, no posteroinferior cerebellar artery involvement, a smaller vertebral-union-basilar angle and vertebral-union-vertebral angle, distal dissection from the VA union, less basilar artery bending, and luminal irregularity/steno-occlusion.