Dynamic computed tomography angiography for noninvasive diagnosis of bow Hunter's syndrome: a case report.

The focus of this case report is to technically describe a noninvasive diagnostic evaluation of bow Hunter's syndrome using a dynamic computed tomography angiography protocol and discuss its advantages. In addition, we aimed to exemplify the quality of the study by presenting images of a 3D-printed model generated to help plan the surgical treatment for the patient. The dynamic computed tomography angiography protocol consisted of a first image acquisition with the patient in the anatomic position of the head and neck. This was followed by a second acquisition with the head and neck rotated to the side that triggered the symptoms, with technical parameters similar to the first acquisition. The acquired images were used to print a 3D model to better depict the findings for the surgical team. The dynamic computed tomography angiography protocol developed in this study helped visualize the vertebrobasilar arterial anatomy, detect vertebral artery stenosis produced by head and neck rotation, depict the structure responsible for artery stenosis (e.g., bony structure or membranes), and study possible complications of the disease (e.g., posterior cerebral circulation infarction). Additionally, the 3D-printed model better illustrated the findings of stenosis, aiding in surgical planning. In conclusion, dynamic computed tomography angiography for the evaluation of bow Hunter's syndrome is a feasible noninvasive technique that can be used as an alternative to traditional diagnostic methods.

Association between cervicocerebral artery dissection and tortuosity - a review on quantitative and qualitative assessment.

Cervicocerebral artery dissection stands out as a significant contributor to ischemic stroke in young adults. Several studies have shown that arterial tortuosity is associated with dissection. We searched Pubmed and Embase to identify studies on the association between arterial tortuosity and cervicocerebral artery dissection, and to perform a review on the epidemiology of cervicocerebral artery tortuosity and dissection, pathophysiology, measurement of vessels tortuosity, strength of association between tortuosity and dissection, clinical manifestation and management strategies. The prevalence of tortuosity in dissected cervical arteries was reported to be around 22%-65% while it is only around 8%-22% in non-dissected arteries. In tortuous cervical arteries elastin and tunica media degradation, increased wall stiffness, changes in hemodynamics as well as arterial wall inflammation might be associated with dissection. Arterial tortuosity index and vertebrobasilar artery deviation is used to measure the level of vessel tortuosity. Studies have shown an independent association between these two measurements and cervicocerebral artery dissection. Different anatomical variants of tortuosity such as loops, coils and kinks may have a different level of association with cervicocerebral artery dissection. Symptomatic patients with extracranial cervical artery dissection are often treated with anticoagulant or antiplatelet agents, while patients with intracranial arterial dissection were often treated with antiplatelets only due to concerns of developing subarachnoid hemorrhage. Patients with recurrent ischemia, compromised cerebral blood flow or contraindications for antithrombotic agents are usually treated with open surgery or endovascular technique. Those with subarachnoid hemorrhage and intracranial artery dissection are often managed with surgical intervention due to high risk of re-hemorrhage.

Bow hunter's syndrome due to an anomalous right vertebral artery origin and contralateral absence: a case report and literature review.

BACKGROUND: Bow Hunter's syndrome (BHS), also known as rotational vertebral artery occlusion (RVAO), is a rare condition characterized by dynamic vertebrobasilar insufficiency due to position-dependent occlusion of the vertebral artery (VA). In the existing literature, most cases of BHS are attributed to osteophytic compression originating from the occipital condyle or within the transverse foramen, often accompanied by anatomical abnormalities of the VA. However, cases presenting solely with VA anomalies in the absence of any cervical vertebral structural abnormality are rare. This case report presents a unique instance of BHS in a 56-year-old male, attributed to the anomalous origin of the right VA and the absence of the left VA, without cervical structural abnormalities. CASE PRESENTATION: The patient exhibited symptoms like episodic dizziness and vertigo, which were exacerbated by rightward head rotation and alleviated upon returning to a neutral position. Diagnostic evaluation, including digital subtraction angiography, revealed that the right VA originated from the right common carotid artery and compression-induced stenosis of the right VA during head rotation. Conservative management, including avoidance of certain head movements and anti-arteriosclerosis medication, led to symptom resolution over a two-year follow-up period. CONCLUSIONS: This report contributes to the understanding of BHS by highlighting a rare vascular anomaly presentation and incorporates a review of 14 similar case reports in the literature describing that an anatomical abnormality of the VA is mainly responsible for the pathology of BHS in the absence of cervical vertebral anomalies, thus emphasizing the need for careful diagnostic and management strategies.

How I do it: Sternocleidomastoid sparing approach for the right vertebral artery to common carotid artery transposition.

BACKGROUND: Direct surgery is an important option to treat vertebral artery (VA) stenosis. METHOD: A patient with symptomatic stenosis at the origin of the right VA underwent transposition of the right VA to the common carotid artery (CCA). Using the sternocleidomastoid sparing approach, the VA was anastomosed to the posterior wall of the CCA by twisting the CCA to expose its posterior wall to face the operative field. CONCLUSION: This approach, consisting of securing the proximal VA and then following it to its distal end, not only preserves the sternocleidomastoid muscle but also protects the sympathetic chains and thoracic duct.

A multidimensional pre-operative planning method of unruptured vertebral artery dissecting aneurysms using three-dimensional AWE mapping and hemodynamic simulation.

OBJECTIVE: High-resolution magnetic resonance imaging (HR-MRI) can provide valuable insights into the evaluation of vascular pathological conditions, and 3D digital subtraction angiography (3D-DSA) offers clear visualization of the vascular morphology and hemodynamics. This study aimed to investigate the potential of a multimodal method to treat unruptured vertebral artery dissection aneurysms (u-VADAs) by fusing image data from HR-MRI and 3D-DSA. METHODS: This observational study enrolled 5 patients diagnosed with u-VADAs, who were scheduled for interventional treatment. The image data of HR-MRI and 3D-DSA were merged by geometry software, resulting in a multimodal model. Quantified values of aneurysm wall enhancement (AWE), wall shear stress (WSS), neck velocity, inflow volume, intra-stent flow velocity (ISvelocity), and intra-aneurysmal velocity (IAvelocity) were calculated from the multimodal method. RESULTS: We found the actual lengths of u-VADAs in the multimodal model were longer than the 3D-DSA model. We formulated surgical plannings based on the WSS, IA velocity, and neck velocity. The post-operative value of IAvelocity, neck velocity, and follow-up quantified values of AWE were decreased compared with the pre-operative condition. After that, u-VADAs were complete occlusion in four patients and near-complete occlusion in one patient during the 6th-month follow-up after surgery. CONCLUSION: The multidimensional method combining HR-MRI with 3D-DSA may provide more valuable information for treating VADAs, with the potential to develop effective surgical planning.

Treatment of acute basilar artery occlusion by retrograde puncture via the vertebral artery approach: A care-compliant case report.

BACKGROUND: Vertebral artery stump syndrome (VASS) is a cause of acute stroke. Owing to the particularity of the pathogenesis of VASS, interventional treatment of VASS is difficult. Common mechanical thrombectomy approaches include femoral and radial artery approaches. However, conventional approaches may not be suitable for VASS. If effective measures are not taken to open offending vessels in time, this can lead to a high rate of disability. In recent years, no consensus has been reached regarding surgical methods for treating VASS. PATIENT CONCERNS: The patient presented to the emergency department with a 2-hour history of disturbance of consciousness. DIAGNOSIS: After neurological and magnetic resonance imaging examinations, the patient was diagnosed with acute large vessel occlusive posterior circulation cerebral infarction. METHODS: The patient's symptoms were not relieved after intravenous infusion of argatroban (10 mg) at a local hospital. We first attempted to open the occluded vertebral artery through normal approaches but failed. We then punctured the vertebral artery, successfully opened the occluded vertebral artery, and performed mechanical thrombectomy. RESULTS: The patient underwent successful vertebral artery puncture and mechanical thrombectomy, with no evidence of postoperative bleeding or vascular injury at the puncture site. The patient regained consciousness the day after surgery but remained impaired in physical activity. After 4 months of rehabilitation, the patient recovered completely. CONCLUSION: When the conventional approach cannot meet the requirements of mechanical thrombectomy, reverse puncture of the vertebral artery is a feasible surgical method for patients with VASS. However, due to the small number of cases, a series of safety problems such as potential puncture failure, hemorrhage after puncture, and vascular occlusion still need to be further explored.

[Perfusion Methods and Reconstruction Techniques for Performing Aortic Arch Surgery with Isolated Left Vertebral Artery].

In our institution, when we perform aortic arch surgery with isolated left vertebral artery using an extracorporeal circulation, we select an interposed saphenous vein graft technique. This technique has a relatively short clamping time and allows for selective cerebral perfusion and flexible choice of reconstruction site. Although other techniques, such as an island reconstruction, have been reported, we do not perform it often due to its longer ischemic time of the left vertebral artery. On the other hand, we use a direct reconstruction technique in cases where an extracorporeal circulation is not used. This direct reconstruction technique in cases of isolated left vertebral artery could reduce the time and number of clamping it.

Bridge-layered decompression technique for vertebral artery-involved hemifacial spasm: technical note.

BACKGROUND: Hemifacial spasm (HFS) is most effectively treated with microvascular decompression (MVD). However, there are certain challenges in performing MVD for HFS when the vertebral artery (VA) is involved in compressing the facial nerve (VA-involved). This study aimed to introduce a "bridge-layered" decompression technique for treating patients with VA-involved HFS and to evaluate its efficacy and safety to treat patients with HFS. METHODS: A single-center retrospective analysis was conducted on the clinical data of 62 patients with VA-involved HFS. The tortuous trunk of VA was lifted by a multi-point "bridge" decompression technique to avoid excessive traction of the cerebellum and reduce the risk of damage to the facial-acoustic nerve complex. To fully decompress all the responsible vessels, the branch vessels of VA were then isolated using the "layered" decompression technique. RESULTS: Among the 62 patients, 59 patients were cured immediately after the surgery, two patients were delayed cured after two months, and one had occasional facial muscle twitching after the surgery. Patients were followed up for an average of 19.5 months. The long-term follow-up results showed that all patients had no recurrence of HFS during the follow-up period, and no patients developed hearing loss, facial paralysis, or other permanent neurological damage complications. Only two patients developed tinnitus after the surgery. CONCLUSION: The "bridge-layered" decompression technique could effectively treat VA-involved HFS with satisfactory safety and a low risk of hearing loss. The technique could be used as a reference for decompression surgery for VA-involved HFS.

Duplication of right vertebral artery in Klippel-Feil anomaly.

The duplicated origin of the vertebral artery (VA) is an uncommon anatomical variant, which is generally identified incidentally during angiography and can be misdiagnosed as dissection in the setting of posterior circulation stroke. Here, we describe a case of the right V1 VA duplication with embryological aspects in a patient with Klippel-Feil anomaly, which was diagnosed during preoperative evaluation. Surgeons must be aware to avoid vascular injury from a duplicated VA before head-neck and spinal surgery.

Occipital artery to vertebral artery bypass for treatment of bilateral vertebral artery occlusion with QMRA as an adjunct to diagnostic assessment.

PURPOSE: Stroke, the second leading cause of death globally, often involves ischemia in the vertebrobasilar territory. This condition is underexplored, despite significant morbidity and mortality risks. The purpose of this study is to present a case of occipital artery to V3 segment vertebral artery bypass, emphasizing the role of quantitative magnetic resonance angiography (qMRA) in assessing flow and guiding surgical intervention. METHODS: A 66-year-old man with bilateral vertebral artery occlusion presented acute symptoms. qMRA was employed to evaluate flow dynamics and determine the feasibility of a flow augmentation bypass surgery. The occipital artery to left vertebral artery bypass (OA-to-VA) was performed, utilizing an inverted hockey-stick incision and an antegrade inside-out technique. The patency of the bypass was confirmed using both Doppler probe and Indocyanine green. RESULTS: Postoperative assessments, including computed tomography angiography (CTA) and qMRA, demonstrated the patency of the bypass with improved flow in the basilar artery and left vertebral artery. The patient's condition remained stable postoperatively, with residual peripheral palsy of the left facial nerve. CONCLUSION: In conclusion, the presented case illustrates the efficacy of the OA-to-VA bypass in addressing symptomatic bilateral vertebral artery occlusion. The study underscores the pivotal role of qMRA in pre- and postoperative assessments, providing noninvasive flow quantification for diagnostic considerations and long-term follow-up in patients with vertebrobasilar insufficiency.

[Anatomical Variations to the Vertebral Artery and Posterior Inferior Cerebellar Artery are Associated with the Partial Persistence of Primitive Lateral Basirovertebral Anastomosis].

The angioarchitecture of the hindbrain is homologous to that of the spinal cord, and its vascular system can be analyzed at the longitudinal and axial structures. During embryonic development, there are two main longitudinal arteries: the longitudinal neural artery and the primitive lateral basilovertebral anastomosis. Commonly observed variations are formed by the fenestration and duplication of either the vertebrobasilar artery, or cerebellar artery, which can be observed when the primitive lateral basilovertebral anastomosis partially persists. Understanding the pattern and development of blood supply to the hindbrain provides useful information of various anomalies in the vertebrobasilar junction and cerebellar arteries.

[Persistent Primitive Arteries].

Primitive anastomotic arteries temporarily exist between the future internal carotid and vertebrobasilar arteries during the early embryonic period(between 28 and 32 days of life). The primitive trigeminal, otic, hypoglossal, and proatlantal intersegmental arteries serve as major blood channels to the developing vertebrobasilar circulation at this stage. These arteries are replaced by the posterior communicating and vertebral arteries, and the primitive anastomotic arteries rapidly regress following the development of the definitive vertebrobasilar circulation. Occasionally, these primitive anastomoses persist and are incidentally discovered after birth. Physicians who treat cerebrovascular diseases should be familiar with the anatomy and functions of these vessels. In this review, we discuss the embryonic basis of the carotid-vertebrobasilar anastomoses and the clinical significance of their persistent forms in adults.

Assessment of Dynamic Cerebral Autoregulation During Long-Term Exposure to High Altitude in Normal Subjects by Ultrasonography.

PURPOSE: To evaluate changes in dynamic cerebral autoregulation (CA) during short-term and long-term exposure to high altitude with ultrasonography, and also study the sex differences in the response of CA to altitude. METHODS: We assessed the differences in dynamic CA and measured with Doppler ultrasound of the bilateral internal carotid artery (ICA), vertebral artery (VA), and middle cerebral artery (MCA) and the values of basic information within 48 hours and at 2 years after arrival at Tibet in 65 healthy Han young Chinese volunteers, meanwhile, we compared the resistance index (RI) and pulsatility index (PI) of the right MCA at inhale oxygen 8 minutes when a newcomer with 2 years after arrival at Tibet. RESULTS: With 2 years of altitude exposure, the SaO2 of all subjects was above 90%, the mean PEF, DAP, and HR values decreased, HGB increased compared within 48 hours in same-gender groups. Comparisons of cerebral hemodynamics between before 2 years and after 2 years within male and female groups, the mean RI and PI values of bilateral MCA after 2 years were significantly higher than before 2 years, at the same time, the mean RI and PI values of bilateral ICA were significant differences (P < .05) between male groups, with regard to female groups, showed that the mean RI and PI values of bilateral VA were significant differences (P < .05). Comparisons of Right MCA hemodynamics between after oxygen uptake 8 minutes and 2 years, the mean RI and PI values were no significant difference within male and female groups (P > .05). CONCLUSIONS: Acute mountain sickness could result from an alteration of dynamic autoregulation of cerebral blood flow, but the impaired autoregulation may be corrected with the extension of time, furthermore, the response of CA to altitude in males and females are different.

Anatomy of vertebral artery hypoplasia and its relationship with clinical implications: a systematic review and meta-analysis of prevalence.

PURPOSE: The vertebral artery (VA) is a vital branch of the subclavian artery, coursing through the transverse foramina of the cervical vertebrae, and playing a crucial role in irrigating the posterior region of the arterial cerebral circle, also known as the Polygon of Willis. Among the various possible alterations that can affect the VA, vertebral artery hypoplasia (HAV) emerges as a significant variant. This study aims to discern the anatomical features of HAV and its correlation with the clinical conditions of the posterior cerebral circulation. METHODS: The databases Medline, Scopus, Web of Science, Google Scholar, CINAHL, and LILACS were searched until January 2024. Two authors independently performed the search, study selection, and data extraction. Methodological quality was evaluated with an assurance tool for anatomical studies (AQUA). Pooled prevalence was estimated using a random effects model. RESULTS: A total of 24 studies met the established selection criteria, with a total of 8847 subjects. In this study, 6 articles were included for the meta-analysis with a total of subjects. The average prevalence of VAH reported in each study was 11% (95% CI 10-12%); the studies had a heterogeneity of 41% based on the funnel plot and a low risk of bias. CONCLUSION: The prevalence of VAH is low, but in the presence of this condition, the changes are mainly in diameter rather than morphological. If it is present, some clinical safeguards must be taken to avoid complications such as stroke.

Vertebral Artery Stenting for Acute Multiple Cerebral Infarctions Caused by Vertebral Artery Dissection After Massage: A Case Report.

Vertebral artery dissection is a rare pathology that can cause ischemic stroke in young people. Cervical massage, especially improper pulling manipulation, is a cause of vertebral artery dissection. We present a case of 32-year-old woman who developed acute multiple posterior circulation ischemic cerebral infarctions as a result of left vertebral artery V4 segment dissection after receiving neck massage. She underwent emergency vertebral artery stent implantation at the site of the dissection. Symptoms were relieved the day after treatment. The patient recovered without adverse complications or endovascular restenosis in the following year.

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

BACKGROUND: 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). METHODS AND RESULTS: 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). CONCLUSIONS: 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.

Ruptured aneurysm in collateral arteries with blood-flow impairment of posterior inferior cerebellar artery: a report of three cases.

Herein, we report three cases of cerebellar hemorrhage due to a ruptured small aneurysm located on a collateral artery compensating for one or more stenotic or occluded major cerebellar arteries. In each case, endovascular distant parent artery occlusion of both the collateral artery and aneurysm was performed to prevent rebleeding. A ruptured small aneurysm in a collateral artery may be observed in patients with hemorrhage in an atypical cerebellar region, especially in cases of stenosis or occlusion of the vertebral artery or posterior inferior cerebellar artery. Thus, cerebral angiography is recommended to rule out collateral artery aneurysm.

Delimitation of the risk area of the vertebral artery during the paramedian suboccipital approach.

OBJECTIVE: The V3 segment of the vertebral artery (V3-VA) is at risk during diverse approaches to the craniovertebral junction. Our objective is to present a system of anatomic and topographic landmarks to identify the V3-VA during the paramedian suboccipital approach (PMSOA) with the help of minimal or basic tools. MATERIAL AND METHODS: The first was a retrospective analysis of the angiotomography (CTA) of 50 patients over 18-years old, and 9 anatomical dissections. A series of lines were defined between the different bony landmarks. Within this lines the risk area of the vertebral artery (RAsV3-VA) and the risk point of the vertebral artery (RPsV3-VA) were defined. The second stage was a prospective study, where the previously defined measurements were carried out by using neuronavigation in 10 patients (20 sides) operated with the PMSO approach in order to confirm the presence of the V3 segment in the RAsV3-VA and RPsV3-VA. RESULTS: In the first stage, the V3 segment was found in the middle third of the X line in 96,6% of the cases. The distance between the inion and the UCP (percentile 5) was 20 mm and to the LCP (percentile 95) was 40 mm. In the range between the UCP and the LCP, in the middle third of the inion-mastoid line (RAsV3-VA), we found 90% of the V3-VA. The measurements taken during the second stage revealed that the artery was in the middle third of the X line in 97% of the cases. 85% of the patients presented the total of the V3s-VA on the RAsV3-VA and in 85% there was a direct relationship with the V3 segment and the RPV3s-VA. CONCLUSION: We propose an easy-to-implement system to delimit the risk area of the V3-VA during the PMSOA. We believe that these landmarks provide a practical, reliable, costless and useful tool that could decrease the risk of lesion of the V3-VA during this approach without the need of using.

Vertebral artery dissection as the underlying cause of ventral spinal epidural haematoma.

Spontaneous spine epidural haematoma is a rare occurrence, with an incidence of 0.1/100 000 inhabitants/year. The anterior location of the haematoma is very uncommon since the dural sac is firmly attached to the posterior longitudinal ligament. Vertebral artery dissection as its underlying cause is an exceptionally rare event, with only two documented cases.This article presents the case of young woman who arrived at the emergency room with a spinal ventral epidural haematoma extending from C2 to T10, caused by a non-traumatic dissecting aneurysm of the right vertebral artery at V2-V3 segment. Since the patient was tetraparetic, she underwent emergent laminectomy, and the vertebral artery dissection was subsequently treated endovascularly with stenting.Vertebral artery dissection with subsequent perivascular haemorrhage is a possible cause of spontaneous spine epidural haematoma, particularly when located ventrally in the cervical and/or high thoracic column. Hence the importance of a thorough investigation of the vertebral artery integrity.