Contralateral Vertebral Artery Research Articles

Efficacy and safety of the contralateral approach to vascular lesions in the vertebral artery: patient series.

Endovascular treatment is preferred over microsurgical clipping for intracranial aneurysms in the posterior circulation. However, access to lesions, particularly those in the regions of the vertebral artery (VA) and the posterior inferior cerebellar artery (PICA), is technically challenging in terms of the vessel diameter of the ipsilateral VA or the branching angle of the PICA. Nine cases of intracranial aneurysms in the region of the PICA, which were endovascularly treated with an approach beyond the vertebrobasilar junction (VBJ) from the contralateral VA in the last 4 years, are described herein. All procedures, namely stent deployment, the use of a balloon catheter, and coiling, were safely performed using the contralateral approach. Neither rebleeding nor ischemic complications occurred. All patients had favorable outcomes and no recurrence. All aneurysms were successfully treated using an adjunctive technique with an additional approach beyond the VBJ from the contralateral VA. The combination of both ipsilateral and contralateral approaches to VA-PICA or PICA lesions contributes to safe and effective endovascular treatment. https://thejns.org/doi/10.3171/CASE24420.

Association of Subclavian Steal Phenomenon with Prevalence of Contralateral Vertebral Artery Atherosclerotic Stenosis: A Hospital-Based Cohort Study.

It is uncertain if there is a connection between subclavian steal phenomenon (SSP) and atherosclerotic stenosis in the opposite vertebral artery (VA). We aimed to explore the association between SSP and the incidence of contralateral vertebral artery stenosis (VAS) in vivo. In this prospective registry study, we included patients diagnosed with ＞50% stenosis of proximal subclavian artery (SA) or innominate artery (INA) by digital subtraction angiography (DSA) from our comprehensive stroke center between 2011 and 2022. VAS and SSP was diagnosed by DSA in the resting state. Propensity score matching (PSM) was conducted among all participants and subgroups with a 1:1 ratio according to the presence of SSP. We further conducted sensitivity analysis by dividing all participants into subgroups according to the degree of stenosis and type of SSP. Binomial logistic regression analysis was applied to investigate the association of SSP with contralateral VAS. A total of 774 patients were included in this study and 309 (39.9%) were found with SSP. After PSM, presence of SSP was associated with lower prevalence of contralateral VAS among all participants (OR 0.45; 95% CI 0.31-0.65; p＜0.001). In subgroup analysis, the association was respectively found within left subclavian (LSA) stenosis group (OR 0.43; 95% CI 0.29-0.65; P＜0.001) and right subclavian artery (RSA) / INA stenosis group (OR 0.36; 95% CI 0.19-0.69; P=0.002). SSP is associated with lower prevalence of contralateral VAS.

Safe Endovascular Recanalization of Internal Carotid Artery Occlusion Using Retrograde Aspiration Angiography

ObjectsCerebral infarction, resulting from acute internal carotid artery (ICA) occlusion, typically manifests with a wide ischemic area and severe symptoms. Mechanical thrombectomy proves effective within 24 hours of disease onset and in less ischemic infarction core. However, in cases with well-developed collateral flow and mild symptoms, conservative treatment is initially selected. If symptoms worsen or ipsilateral hemisphere perfusion decreases, superficial temporal artery (STA) – middle cerebral artery (MCA) anastomosis is considered. Revascularization therapy may also be effective. Contralateral angiography allows for ipsilateral blood flow verification once complete revascularization is achieved, albeit with potential treatment-related complications. Here, we describe retrograde angiography using an intermediate catheter (IMC) and contralateral contrast injection to achieve safer revascularization. MethodsWe present ten acute ICA occlusion cases caused by thromboembolism, arteriosclerosis, carotid artery stent occlusion, or embolic stroke of undetermined source. Employing bilateral femoral artery puncture, one catheter was guided to the occluded ICA, while another was positioned for diagnostic purposes in the contralateral ICA or vertebral artery. The IMC was navigated through the occluded vessel, with contralateral imaging performed during aspiration. The catheter was gradually retracted to confirm the extent of occlusion and recognize recanalization. ResultsRecanalization was successfully achieved in all cases. Symptomatic ischemic complication and hyperperfuison was not seen in all cases. No cases were decreased modified Rankin scale after treatment. ConclusionAdvancements in IMC technology facilitate distal catheter guidance to the ICA, even in proximal occlusion. Combining this technique with contralateral imaging allows us to confirm the extent of occlusion and recanalization status without antegrade imaging, making recanalization therapy safer.

Conventional and old endovascular techniques for vertebral aneurysms still work in the era of flow diversion

BackgroundEndovascular management for vertebral artery dissecting aneurysms (VADA) is quite intricate which thereby necessitate different strategies per case. Our current study described various optimal strategies available for endovascular management of VADA other than flow diverter (FD).Results14 Patients presented with acute SAH and 4 patients with symptoms of mass effect. VADA were classified in 3 groups, viz contralateral vertebral artery is dominant group A (n = 5), co-dominant group B (n = 8) or group C hypoplastic (n = 5). Group A and B (n = 13) was further subdivided into three subtypes depending on location of aneurysm with respect to posterior inferior cerebellar artery (PICA), aneurysm proximal to the PICA, type I (n = 5); involving the PICA, type II (n = 1); and distal to the pica, type III (n = 4). Treatment strategy varied with type whether deconstructive or reconstructive methods using stents and coils in different fashion.ConclusionPreprocedural angiographic work up delineating the anatomical location of the aneurysm, contralateral vertebral artery dominancy and nearby perforator status along with location of PICA is imperative in selecting the safest and optimal endovascular therapy option.

Indications, operative techniques, and outcomes of occipital artery-vertebral artery bypass: an institutional series.

Posterior circulation cerebral bypasses often show higher risks and lower patency. Only few reports discussed occipital artery (OA)-vertebral artery (VA) bypasses. We present our illustrative cases to address current gaps in the literature on OA-VA bypass. A single-center retrospective review was conducted to include all institutional cases of OA-VA bypass, discussing the technique and outcomes. Four institutional cases undergoing a total of 5 bypasses were evaluated, including 3 males and 1 female, with median age of 65years (range, 62-73). All patients had vertebrobasilar insufficiency (VBI) with recurrent strokes/TIAs due to intracranial atherosclerosis, leading to unilateral VA stenosis with contralateral occlusion (1, 25%), bilateral VA stenosis (1, 25%) or occlusion (1, 25%). Medical management included aspirin for all cases (100%), with clopidogrel in 3 (75%). Surgery was performed through a far lateral approach, connecting the OA to the VA-3 segment, with no inter-positional graft. One patient underwent contralateral OA-VA bypass 6months after the prior surgery due to worsening of the contralateral VA stenosis. Bypass patency was confirmed in all cases with post-operative angiography. All patients had clinical improvement, with one case of wound dehiscence managed conservatively. All patients were alive at last follow-up (median 7.0months; range: 1.5-18). OA-VA bypass is a challenging yet effective strategy in selected patients with VBI. Current literature lacks unique definitions of surgical indications and techniques, which we addressed in our series. Surgical education should focus on expanding the microsurgery anatomy knowledge.

Strain of the vertebral artery during passive neck movements and spinal manipulation of the cervical spine: An observational study

BackgroundNeck pain is a common condition, and a frequent treatment is chiropractic cervical spinal manipulation therapy (cSMT). However, cervical spinal manipulations have been associated with excessive cervical artery elongations, allegedly causing arterial dissection leading to stroke. PurposeThe primary purpose of this study was to quantify the total vertebral artery elongations during cSMT, and secondarily, quantify the vertebral artery elongations during the pre-manipulative orientation of the head and neck and the subsequent elongations during the actual thrust. MethodsVertebral artery strains were measured at the cervical levels C0–C1, C1–C2, and C2–C3 using piezoelectric crystals that were sutured to the wall of the left and right vertebral artery in three cadavers. Vertebral artery strains were measured continuously for a full set of passive range of motion testing and for the chiropractic spinal manipulation. FindingsFor the range of motion testing, the greatest average vertebral artery strains at the C0–C1 level were 6.9% for ipsilateral flexion-rotation, at the C1–C2 level 4.3% for contralateral rotation, and at the C2–C3 level 3.7% for contralateral flexion-rotation. For the chiropractic spinal manipulation, the average maximal strains at the C0–C1, C1–C2 and C2–C3 levels were 1.3%, 0.1%, and 1.0%, respectively. The maximal average vertebral artery strains in the pre-manipulative phase were 0.5% and the corresponding maximal vertebral artery strains during the manipulative thrust was 1.1%. InterpretationPassive range of motion testing produced strains in the vertebral artery were 5.3 times (C0–C1), 7.2 times (C1–C2), and 3.7 times (C2–C3) greater than the corresponding strains during chiropractic spinal manipulation, suggesting that strains in the vertebral artery during chiropractic spinal manipulation were much smaller than the strains that can occur during normal everyday movements of the head and neck. Furthermore, vertebral artery strains in the pre-manipulative phase did not contribute to the peak strains on the contralateral vertebral artery and helped reduce strains on the ipsilateral side.

Analysis of the clinical characteristics of V4 segment steal blood in the vertebral artery

Objective: To explore the clinical characteristics of unilateral vertebral artery V4 segment occlusive lesions (severe stenosis or occlusion), where the contralateral vertebral artery can be compensated through blood flow and reverse supply to the posterior inferior cerebellarartery (PICA). Methods: This study is a retrospective case series of 66 patients with V4 segment occlusive lesions of unilateral vertebral artery diagnosed and treated from June 2020 to October 2022. Patient data were retrospectively collected, and their hemodynamic characteristics and imaging data were analyzed. Results: Of the 66 cases, 11 patients (16.7%) with V4 segment occlusive disease showed the blood flow of the vertebral artery on the opposite side of the lesion on the digital subtraction angiography (DSA), which can be reverse stolen to the posterior inferior cerebellar artery of the diseased side through the confluence point of the vertebrobasilar artery through the distal end of the ipsilateral vertebral artery V4. Owing to the lack of literature on this pathway and based on the characteristics of previous definitions of subclavian artery steal and carotid artery steal, we referred to this pathway as the vertebral artery V4 segment steal. In 6 patients (9.1%), transcranial Doppler ultrasound (TCD) and transcranial color Doppler ultrasound (TCCD) showed that the blood flow signal was not detected at the proximal end of the V4 segment of the affected side, rather the blood flow direction was reversed at the distal end of the V4 segment, resulting in compensatory acceleration of the blood flow velocity of the V4 segment of the contralateral vertebral artery. Conclusion: "V4 segment steal of vertebral artery" is a very rare route of vertebral artery steal. When V4 segment of the vertebral artery is occluded, clinicians should pay attention to observe the blood supply of PICA and whether there is such a steal route, to better evaluate the blood flow compensation and prognosis of patients.

Association Between Vertebral Arterial Tortuosity and Aneurysm Growth in Intracranial Vertebral Artery Dissection.

An intracranial vertebral artery dissecting aneurysm (iVADA) increases the risk of future subarachnoid hemorrhage, which is a severe complication with high rebleeding rates and poor outcomes. Identifying potential risk factors associated with iVADA growth is crucial for their effective management. This observational study was carried out at a single center and included patients who had been diagnosed with iVADA based on neuroimaging findings. We divided the patients into two groups: with and without iVADA growth. Growth was defined as any enlargement of a dilated region or a morphological change in follow-up imaging. We measured the vertebral artery tortuosity index (VTI) in the contralateral vertebral artery (VA), defined as its actual length divided by its straight length. We investigated the factors associated with iVADA growth. This study included 124 patients. The median follow-up period was 7 months. We observed iVADA growth in 54 patients (43.5%), who were more likely to be current smokers (33.3% vs. 14.3%, p=0.012) and have a higher VTI (1.14±0.11 [mean±standard deviation] vs. 1.06±0.12, p=0.035) compared with those without iVADA growth. A multivariate analysis revealed that the VTI (adjusted odds ratio=28.490, 95% confidence interval=1.025-792.046, p=0.048) was independently associated with iVADA growth. This study has identified an independent association between VA tortuosity and iVADA growth.

A case of contralateral vertebral artery dissection during ramucirumab plus nab-paclitaxel combination therapy with a history of unilateral vertebral artery dissection

A case of contralateral vertebral artery dissection during ramucirumab plus nab-paclitaxel combination therapy with a history of unilateral vertebral artery dissection

Abstract 114: “Failing” DAPT? Think Again

Introduction Bow Hunter’s Syndrome (BHS) is a rare etiology of vertebrobasilar insufficiency that usually occurs with head turn, which causes compression of the vertebral artery by an osteophyte. There is subsequent hypoperfusion of brain tissue, but thromboembolism and ischemic stroke is rare. Timely diagnosis is imperative, as decompressive surgery can be curative. This unique case highlights the diagnostic and therapeutic challenges of a patient with multiple vascular risk factors who suffered from strokes secondary to BHS. Methods A 79‐year‐old man with a past medical history of peripheral artery disease, abdominal aortic aneurysm, myocardial infarction with drug eluding stents (on dual antiplatelet therapy (DAPT)), complete heart block with pacemaker, heart failure with reduced ejection fraction, hypertension, hyperlipidemia, and diabetes mellitus presented to an outside hospital with recurrent episodes of right‐sided weakness every 1‐2 days over the previous 3 weeks. Episodes always occurred after activity and only upon sitting. He had previously undergone non‐contrasted head computed tomography (NCHCT) (magnetic resonance imaging (MRI) was unable to be performed secondary to pacemaker), which did not reveal strokes. His initial computed tomography angiogram (CTA) of the head and neck was unremarkable. However, CTA head and neck 4 days later demonstrated 90 percent stenosis of the mid left V2 at the C3‐4 level and a 75‐90 percent stenosis of the left mid V2 segment at the C5‐6 level (hard and soft plaque in these areas). He was switched from DAPT to aspirin and warfarin because he was considered a “DAPT failure.” He continued to have episodes, so he was transferred to our institution for a second opinion. Results On arrival, the exam was notable for right‐sided hemiparesis and dysmetria. Repeat CTA head and neck demonstrated multifocal intracranial atherosclerosis with marked stenosis of the left V4 segment. However, marked stenosis at V2 appeared to be owed to external compression from facet arthrosis rather than atherosclerosis. He also had moderate stenosis of the right V4 segment. Eventually, he underwent an MRI brain, which demonstrated acute to subacute infarcts in the left pons. He was taken for a cerebral angiogram on the same day, which demonstrated stenosis of the distal V2 segment of the left vertebral artery (at the level of C3‐C4) with interval development of marked stenosis following neck flexion and occlusion of the left vertebral artery following leftward head rotation. Findings were most consistent with rotational occlusion of the left vertebral artery, which is also known as BHS. The patient underwent surgery, but suffered from a gastrointestinal bleed and developed post‐operative atrial fibrillation; after a risks/benefits discussion, he was discharged on anticoagulation only. He had no further strokes. Conclusion This patient suffered from ischemic strokes, which occur in less than 10% of BHS cases. Contralateral vertebral artery stenosis, which is unable to supply retrograde flow during compression, is the likely etiology of this patient's strokes. Recurrent posterior circulation strokes in the setting of optimal medical management should clue clinicians to consider other etiologies of stroke. Dynamic angiography is the gold standard for BHS and decompressive surgery is often curative.

Abstract 089: A Case of Complicated Dissection: Vertebral Artery Sacrifice for Recurrent Stroke Prevention

Introduction Posterior circulation strokes account for 20% of ischemic strokes (1). Optimal management for posterior circulation strokes has been studied less than for anterior circulation strokes (2). Endovascular parent vessel sacrifice is an established technique used to treat vascular pathologies. There is limited evidence for parent artery sacrifice for recurrent strokes and there is no current guideline for standard of care. Methods '‐ Results 51‐year‐old gentleman with history of tobacco use presented with left homonymous hemianopsia, onset 1.5 hours prior to arrival. CT brain showed no bleed and patient received IV tissue‐plasminogen activator (tPA). CT angiography (CTA) demonstrated occlusion of the right posterior cerebral artery (PCA) and dissection of the left vertebral artery (V2 segment) with distal reconstitution. He underwent emergent thrombectomy for right P2 thrombus with complete reperfusion TICI 3 (Thrombolysis in Cerebral Infarction Score). Less than 24 hours later, he developed a right homonymous hemianopsia, and was found to have a new occlusion of the left P1 segment of the left PCA. Emergent thrombectomy was performed with complete reperfusion (TICI3). MRI brain demonstrated bilateral PCA territory infarcts. Within 12 hours of the second thrombectomy, his neurological exam deteriorated, and interval imaging revealed a basilar trunk thrombus, for which he underwent a successful endovascular thrombectomy complete reperfusion (TICI3). His antiplatelet regimen was optimized with Aspirin. Heparin was considered as treatment but was not provided because of the hemorrhagic conversion of his ischemic strokes. Given the persistent recurrence of thromboemboli in the posterior circulation despite being on optimal medical management, and evidence of hemorrhagic conversion, a decision was made to perform endovascular coil embolization of the left vertebral artery V2 segment at the site of dissection. Angiographic imaging demonstrated antegrade blood flow through the dissection as the source of recurrent embolic strokes. Six Stryker Target coils were deployed spanning the region of dissection within the left V2 segment via a right radial access with the guide catheter in the right vertebral artery. Post coil embolization angiographic runs demonstrated complete occlusion of the left vertebral V2 segment at the region of dissection which was confirmed via a left vertebral injection from a left femoral arterial access. There was preservation of ascending cervical collaterals beyond the dissection with patency of the contralateral vertebral artery supplying the intracranial circulation. Following embolization, repeat imaging showed no new infarcts and no new or worsening hemorrhage. He was continued on Aspirin monotherapy. It is notable that though his neurological exam deteriorated during each recurrent thromboembolic event, his neurologic exam at the time of discharge significantly improved with NIHSS of 3. He is currently being followed at our neuroscience institute. Conclusion Cervical arterial dissections pose increased risk for ischemic strokes (3). Vertebral artery dissection accounts for approximately 2%, of which, 10‐25% occur in middle‐aged and younger patients (4). This is a case of a young patient that exemplifies a successful role for vertebral artery sacrifice with coil embolization to prevent recurrent thromboembolic posterior circulation strokes. However controlled studies are needed for safety and efficacy of these interventions.

Long‐Term Stability of Patients Undergoing Endovascular Parent Artery Occlusion of Their Intracranial Artery

Background Although endovascular parent artery occlusion (PAO) of the intracranial artery is a well‐established treatment option, the long‐term stability of cerebral blood flow remains a concern. This study aimed to evaluate the long‐term clinical and radiological outcomes of patients who underwent PAO. Methods The patients who underwent endovascular PAO of their internal carotid or vertebral artery (VA) between April 2011 and March 2022 were included in this observational study. Information about patient characteristics, details of the endovascular treatment, and clinical and radiological follow‐up were collected. Results The study included a total of 104 cases (average age, 52.9±12.6 years old; men, 73 [70.2%] cases; 95 [91.3%] VA PAO cases) from 8 centers. Most cases were performed in an emergency condition, such as ruptured VA dissecting aneurysm (73 cases [70.2%]). PAO was successful in all cases. Early stroke (within 30 days) occurred in 33 (31.7%) cases (31 cases in VA PAO and 2 cases in internal carotid PAO) with ischemic stroke (29 cases) comprising the largest group. Clinical follow‐up over 1 month was available in 85 cases. During an average follow‐up period of 45.8±25.8 months, 1 case of VA PAO experienced a stroke without functional deterioration. Imaging follow‐up was performed in 75 cases. Recanalization of the occluded VA was observed in 2 cases. The remaining image change was contralateral VA stenosis after VA PAO. The incidence of clinical and radiological events was 1.2% and 1.1% per patient‐year, respectively. Conclusion Once the patients surpass the acute phase after PAO, their mid‐ to long‐term course was stable. The risk of late stroke or de novo aneurysm formation was lower than expected in the literature, and the direct comparison to novel reconstructive techniques is warranted in future studies. Clinical Trial Registration information: https://www.umin.ac.jp/ctr/index.html , trial ID: UMIN000045160.

Endovascular treatment of acute basilar artery occlusion caused by vertebral artery stump syndrome: A clinical analysis of 37 cases

IntroductionAcute basilar artery occlusion (ABAO) caused by vertebral artery stump syndrome (VASS) has a low incidence and is always underestimated. Due to the occlusion of the origin of the vertebral artery (VA), it is often combined with basilar artery (BA) endovascular diseases or non-dominant contralateral vertebral artery, making the endovascular treatment (EVT) challenging to implement. ObjectiveThis article focuses on whether EVT and two interventional route options could bring clinical benefits to this group of patients: basilar artery thrombectomy through the occluded lateral vertebral artery and implementing revascularization of the occluded vertebral artery (dirty-road-path); thrombectomy through the non-occluded lateral vertebral artery (clean-road-path). MethodsWe collected six cases of acute embolic basilar artery occlusion (ABAO) due to VASS from January 2020 to December 2021 at our hospital and retrospectively analyzed 31 patients previously reported in the literature and applied statistical analysis to investigate the treatment options and clinical prognosis of these patients. ResultsThe clean-road-path surgical protocol was applied in 4 of 37 patients, the dirty-road-path protocol was applied in 29 patients, and 4 patients did not recanalized the basilar artery. By statistical analysis we found that successful recanalization of the basilar artery was clinically significant in reducing the modified Rankin Scale (mRS) scores in these patients, the statistical difference in the benefit of the two surgical protocols was negative. There was a significant positive correlation between preoperative National Institute of Health Stroke Scale (NIHSS) and postoperative 90-day mRS scores. ConclusionEndovascular treatment can benefit patients with ABAO due to VASS, and patients with higher preoperative NIHSS scores are more vulnerable to getting a poor prognosis. Comparison between the two endovascular options did not yield statistically significant results, but the dirty-road-path option may be superior to using the clean-road-path.

Real-Time Monitoring and Modulation of Blood Pressure in a Rabbit Model of Ischemic Stroke.

Control of blood pressure, in terms of both absolute values and its variability, affects outcomes in ischemic stroke patients. However, it remains challenging to identify the mechanisms that lead to poor outcomes or evaluate measures by which these effects can be mitigated because of the prohibitive limitations inherent to human data. In such cases, animal models can be utilized to conduct rigorous and reproducible evaluations of diseases. Here we report refinement of a previously described model of ischemic stroke in rabbits that is augmented with continuous blood pressure recording to assess the impacts of modulation on blood pressure. Under general anesthesia, femoral arteries are exposed through surgical cutdowns to place arterial sheaths bilaterally. Under fluoroscopic visualization and roadmap guidance, a microcatheter is advanced into an artery of the posterior circulation of the brain. An angiogram is performed by injecting the contralateral vertebral artery to confirm occlusion of the target artery. With the occlusive catheter remaining in position for a fixed duration, blood pressure is continuously recorded to allow for tight titration of blood pressure manipulations, whether through mechanical or pharmacological means. At the completion of the occlusion interval, the microcatheter is removed, and the animal is maintained under general anesthesia for a prescribed length of reperfusion. For acute studies, the animal is then euthanized and decapitated. The brain is harvested and processed to measure the infarct volume under light microscopy and further assessed with various histopathological stains or spatial transcriptomic analysis. This protocol provides a reproducible model that can be utilized for more thorough preclinical studies on the effects of blood pressure parameters during ischemic stroke. It also facilitates effective preclinical evaluation of novel neuroprotective interventions that might improve care for ischemic stroke patients.

Successful subclavian artery stenting in a patient with subclavian steal syndrome associated with contralateral vertebral artery hypoplasia.

Successful subclavian artery stenting in a patient with subclavian steal syndrome associated with contralateral vertebral artery hypoplasia.

Different results of vestibular examinations and blood flow in cases with transient vascular vertigo/dizziness with or without central nervous system symptoms

Background The condition of vestibular dysfunction and blood flow in the vertebral artery (VA) in transient vascular vertigo/dizziness (TVV) is not well established. Objectives To clarify the pathophysiology of TVV, especially the difference between the isolation of vestibular symptoms. Materials and methods Ten TVV patients with central nervous system symptoms (TVVw) and 12 TVV patients without central nervous system symptoms (TVVo) underwent duplex color-coded ultrasonographic evaluation of VAs, caloric test, and cervical vestibular-evoked myogenic potential (cVEMP). Results The mean flow velocity (MV) ratio (peak MV of contralateral VA divided by target VA) was significantly higher in TVVw than in TVVo. There was no difference in the occurrence of canal paresis between TVVw and TVVo. Abnormal asymmetry ratios (ARs) of cVEMP were observed only in TVVo cases (6 of 12 cases), revealing a statistically significant difference in the number of cases between TVVw and TVVo. Conclusions and significance Measuring VAs using duplex color-coded ultrasonography and cVEMP may help evaluate TVV. Different results of MV ratio and cVEMP between TVV cases with or without central nervous system symptoms may indicate differences in the pathophysiology between TVVw and TVVo.

A balloon-supported embolism protection technique during vertebral/subclavian artery angioplasty stenting.

A balloon-supported embolism protection technique during vertebral/subclavian artery angioplasty stenting.

Management of posterior circulation tandem occlusions in acute ischemic stroke: Recanalize the dominant vertebral artery with priority.

To illustrate the characteristics of acute ostial vertebral artery (VA) and basilar artery (BA) tandem occlusions. The endovascular treatment strategy for ostial VA-BA tandem occlusion was reported. We conducted a retrospective analysis of patients with ostial VA-BA tandem occlusion who underwent endovascular treatment in our center between November 2018 and February 2022. We preferred to recanalize the dominant vertebral artery with priority. The imaging characteristics, treatment strategy, clinical outcomes, and complications were analyzed. In total, 9 patients with ostial VA-BA tandem occlusion were enrolled in this study. All the VA-BA tandem occlusion was caused by acute occlusion of the dominant VA. Endovascular revascularization was performed through the occluded dominant VA in 8 patients and was performed through contralateral non-dominant VA in 1 patient. Successful recanalization (mTICI 2b/3 grade) was achieved in all 9 patients, and 5 patients (55.5%) achieved functional independence with a mRS score of 0-2 at 90 days. In this case series, the occurrence of ostial VA-BA tandem occlusions was mainly caused by acute occlusion of the dominant VA. Endovascular revascularization of ostial VA-BA tandem occlusions through occluded dominant VA was feasible and recommended.

Angiographic Predictors of Outcomes After Balloon Test Occlusion

Background Balloon test occlusion (BTO) with adjunctive single‐photon emission computed tomography has been used to predict tolerance after permanent internal carotid artery occlusion. Anatomic characteristics of the cerebral circulation might predict BTO outcomes and identify patients susceptible to test failure. Methods We performed a single‐center retrospective analysis of patients who underwent internal carotid artery BTO from July 2013 to June 2020. Patients who passed the clinical BTO underwent single‐photon emission computed tomography imaging; technetium‐99m‐ethyl cysteinate dimer was injected intravenously after 15 to 30 minutes of occlusion and induced hypotension. The diameter of the vessels of the circle of Willis was measured angiographically. Single‐photon emission computed tomography imaging hypoperfusion severity was classified as none, mild, low intermediate, high intermediate, and severe. A threshold vessel diameter with most predicted accuracy for BTO failure was created using the Youden index. The threshold value was tested in a logistic regression for prediction of BTO failure and accuracy as represented with a receiver operator curve. Results Fifty‐seven patients underwent BTO. Neoplasia was the most common indication (n=43, 75%). Twelve (21.1%) patients failed the clinical BTO. Contralateral dominant vertebral artery ( P =0.02), smaller anterior communicating artery (ACom; P =0.002), and ipsilateral posterior communicating artery ( P =0.03) diameters were correlated with clinical BTO failure. Smaller ACom was most predictive with an area under the curve of 0.907. The Youden index identified an ACom diameter threshold of 1.1 mm, with a sensitivity of 91.7% and specificity of 77.8% (odds ratio, 0.026 [95% CI, 0.003–0.226]; receiver operating characteristic, 0.847) for predicting BTO failure. Patients with severe single‐photon emission computed tomography asymmetry had significantly smaller‐caliber ACom arteries (ACom median diameter, 0.95 versus 1.4 mm; P =0.0073). Conclusions Angiographic findings can be used to predict BTO results. A small ipsilateral posterior communicating artery, and more significantly, a small ACom (<1.1 mm) can be used to identify patients who are likely to fail BTO.

Effects of Manual Versus Instrumental Spinal Manipulation on Blood Flow of the Vertebral and Internal Carotid Arteries in Participants With Chronic Nonspecific Neck Pain: A Single-Blind, Randomized Study

ObjectiveThe aim of this study was to compare the hemodynamic effects of manual spinal manipulation (MSM) and instrumental spinal manipulation (ISM) on the vertebral artery (VA) and internal carotid artery (ICA) in participants with chronic nonspecific neck pain (NNP). MethodsThirty volunteers aged 20 to 40 years old with NNP over 3 months duration were included. Participants were randomly divided into the following 2 groups: (1) MSM group (n = 15) and (2) ISM group (n = 15). Ipsilateral (intervention side) and contralateral (opposite side of intervention) VAs and ICAs were evaluated using spectral color Doppler ultrasound before and immediately after manipulation. Measurements were recorded by visualizing the ICA carotid sinus (C4 level) and the VA at the V3 segment (C1-C2 level). The blood flow parameters of peak systolic velocity (PSV), end-diastolic velocity, resistive index, and volume flow (only for VA) were evaluated. The spinal segment, in which biomechanical aberrant movement was detected by palpation in the upper cervical spine, was manually manipulated in the MSM group. The same methodology was performed for the ISM group using an Activator V instrument (Activator Methods). ResultsIntragroup analysis exhibited no statistically significant difference between the MSM and ISM groups in terms of PSV, end-diastolic velocity, resistive index of ipsilateral and contralateral ICA and VA, in addition to volume flow of both VAs preintervention and postintervention (P > .05). Within the intergroup analysis, there was a significant difference in ipsilateral ICA PSV (P = .031) (preintervention vs postintervention difference was –7.9 ± 17.2 cm/s [95% confidence interval, –17.4 to 1.6] in the ISM group and 8.7 ± 22.5 cm/s [95% confidence interval, –3.6 to 21.2]) in the MSM group (P < .05). Other parameters did not show any significant difference (P > .05). ConclusionManual and instrumental spinal manipulations applied to the upper cervical spine in participants with chronic NNP did not appear to alter blood flow parameters of the VAs and ICAs.