Unilateral Vertebral Artery Occlusion Research Articles

Endovascular Management of Basilar Artery Aneurysms: A Consecutive Series of 124 Patients

There is currently no established criterion for determining when interventional treatment is necessary and what strategy is appropriate for basilar artery (BA) aneurysms. Through this study, we aimed to propose an algorithm that can effectively determine the optimal endovascular treatment (EVT) option for BA aneurysms. We enrolled patients with BA aneurysms from June 2016 to December 2022 and performed procedures based on the algorithm. The analysis included demographic, clinical, and aneurysmal characteristics, procedural details, complications, angiographic outcomes, and clinical outcomes. This study included 124 patients (mean age 55.0 years) with a BA aneurysm who underwent EVT. Of these, 21 aneurysms were treated in the setting of subarachnoid hemorrhage (SAH). The majority of aneurysms were located at the basilar apex (74), followed by the basilar trunk (30) and vertebrobasilar junction (20). Coiling was used in 18.5% of cases, while stent-assisted coiling embolization was chosen for 58.9%. Overlapping stents were used in 12.9%, flow diverter (FD) implantation in 3.2%, Y/T stent techniques in 4.8%, and stent adjunctive coiling with unilateral vertebral artery (VA) occlusion in only 1.6%. Procedure-related complications occurred in 15 patients (12.1%). Patients had a modified Rankin Scale(mRS) score of 0.74±1.62; 98 (86.7%) had good prognosis with mRS scores ranging from 0 to 2 at the last follow-up. DSA was performed on 105 (84.7%) patients revealing that 101 (81.5%) achieved complete or near-complete occlusion. The endovascular treatment criteria for BA aneurysms depended on the multi-characteristics was safe and effective. However, further evidence is needed from large cohort studies.

Occlusion of vertebral artery and anterior spinal artery in cervical facet dislocation: a prospective study using computed tomography angiography.

A prospective study. To investigate the incidence of vertebral artery (VA) occlusion and whether anterior spinal artery (ASA) is occluded in cervical facet dislocation. University hospital, China. During a 2-year period, 21 conventional patients with cervical facet dislocation were prospectively enrolled. All patients received computed tomography angiography (CTA) to assess the patency of the VA, anterior radiculomedullary arteries (ARAs), and ASA at the time of injury. Clinical data were documented, including demographics, symptomatic vertebrobasilar ischemia, American Spinal Injury Association Impairment Scale (ASIA) grades, and ASA and VA radiological characteristics. VA unilateral occlusion occurred in 5 of 21 patients (24%), including 2 with unilateral facet dislocation and 3 with bilateral facet dislocation. No ASA occlusion was found in all 21 patients, including 5 with VA unilateral occlusion. No patients had symptomatic vertebrobasilar ischemia. VA occlusion occurs in approximately one-fourth of cervical facet dislocations, with infrequent symptomatic vertebrobasilar ischemia. ASA is not occluded following cervical facet dislocation, even with unilateral VA occlusion.

An analysis of clinical characteristics of rare bilateral medial medullary infarction: An observational study.

This study aimed to characterize the risk factors, etiology, clinical manifestations, anatomical characteristics, stroke mechanisms, imaging features, and prognosis of bilateral medial medullary infarction (BMMI). A retrospective analysis was conducted on 11 patients with BMMI who met the inclusion criteria at the Affiliated Hospital of Xuzhou Medical University from January 2013 to January 2023. The patients' imaging and clinical features were analyzed and summarized. Eleven patients (7 male, 4 female), aged 46 to 62 years, met the inclusion criteria. Common clinical presentations included dysarthria (90.9%), dysphagia (90.9%), quadriplegia (81.8%), and so on. Within 72 hours of onset, 8 cases presented with quadriplegia, 2 cases with hemiplegia, and 1 case without limb paralysis. The main risk factor for BMMI was hypertension, followed by diabetes. "Heart appearance" infarcts occurred in 4 cases (36.4%), while "Y appearance" infarcts occurred in 7 cases (63.6%). Among the patients, 3 had unilateral vertebral artery stenosis or occlusion, 5 had bilateral vertebral artery stenosis or occlusion, 2 had normal vertebral basilar artery, and 1 did not undergo cerebrovascular examination. All patients received standardized treatment for cerebral infarction. The prognosis was poor, with 81.8% of patients having an unfavorable outcome, including 1 death, 9 cases of disability, and only 1 patient achieving self-care ability after recovery. BMMI is more prevalent in males aged 45 to 60 years. The main risk factors are hypertension and diabetes. Atherosclerosis is the primary etiological subtype. The main clinical manifestations are dyskinesia, dizziness, quadriplegia, and dysarthria. The prognosis of BMMI is poor. The specific imaging features of "heart appearance" or "Y appearance" infarcts aid in the diagnosis of BMMI.

A case of suspected vertebral artery stump syndrome assessed by CT angiography

A 55-year-old man developed ischemic stroke in the bilateral cerebellar hemispheres and bilateral occipital lobes. He was admitted to our hospital 17 months later with recurrent ischemic stroke in the posterior circulation. The left vertebral artery (VA) was occluded on brain magnetic resonance angiography but was visualized with a delay on continuous three-phase CT angiography (CTA). Conventional angiography confirmed a to-and-fro blood flow pattern at the distal end of the left VA, therefore the patient was diagnosed with VA stump syndrome (VASS). VASS is a recurrent posterior circulation ischemic stroke caused by thrombi in an occluded unilateral VA. VASS should be suspected in patients with unilateral VA occlusion and repeated posterior-circulation ischemic stroke. The diagnostic criteria for VASS include confirmation of VA occlusion and the presence of an antegrade flow component at the distal end. In this case, the presence of collateral circulation in the VA was suspected based on CTA findings, leading to the diagnosis of VASS. It was thus suggested that devising the imaging method of CTA may help diagnose VASS.

Endovascular Management of Vertebrobasilar Trunk Artery Large Aneurysms: Complications and Long-Term Results.

ObjectiveTo analyze the complications and long-term results of endovascular management of vertebrobasilar trunk large (≥10 mm) aneurysms (VBTLAs) and identify predictors of outcomes.MethodsBetween 2014 and 2020, 6,987 patients with intracranial aneurysms were referred to our center for aneurysm management and 2,224 patients have undergone the endovascular procedures. We retrospectively reviewed the database and identify all the patients with VBTLAs.ResultsA total of 62 VBTLAs were identified. The median aneurysm size was 13.4 mm [interquartile range (IQR) 11.5–18.7]. Among them, 24 aneurysms were treated with overlapping stent techniques, 18 aneurysms were treated with flow diversion, 14 aneurysms were treated with single stent-assisted coiling, and 6 aneurysms were treated with coiling alone. Ten patients were treated with parent artery occlusion or unilateral vertebral artery occlusion. Periprocedural complications were occurred in 7 (11.3%) patients. Clinical follow-up was obtained at the median of 27.5 months (IQR 15.3–58.5). The overall complication rate was 16.1% (10/62), including nine ischemic events and one hemorrhagic event. The combined disability and neurological mortality rate was 12.9% (8/62), with 4 (6.5%) deaths. The favorable outcome rate at follow-up was 87.1% (54/62). The complication-free cumulative survival rates at 1 and 5 years were 86.8 and 82.0%, respectively. The overall cumulative survival rates at 1 and 5 year were 96.5 and 89.8%, respectively. In the multivariate Cox regression analysis, longer procedure time (>115 min) (P = 0.037) and ischemic onset (P = 0.005) predict complications. Angiography follow-up was available for 36 patients at the median of 6.0 months (IQR 6–12), with a complete occlusion rate of 77.8% (28/36). Two (5.6%) aneurysms were recanalized and subsequently received the retreatment. Subgroup analysis did not find any differences in the complete occlusion rate between endovascular strategies.ConclusionEndovascular management of VBTLAs has a reasonable safety profile with favorable 5-year cumulative survival rates and imaging outcomes at follow-up. Prolonged procedure and ischemic onset are associated with a high risk of overall complications.

Abstract P715: Vertebral Artery Occlusive Dissection Score in Acute Ischemic Stroke

Background and purpose: The discrimination of vertebral artery (VA) occlusive dissection from other etiologies is critical for acute stroke management but sometimes difficult. We aimed to assess the factors associated with VA occlusive dissection and develop the discrimination score. Methods: We examined consecutive patients with acute posterior ischemic stroke due to unilateral VA occlusion from our prospective stroke registry between 2012 and 2019. Unilateral VA occlusion was confirmed by magnetic resonance angiography and cervical ultrasonography. The diagnosis of VA dissection was based on the magnetic resonance imaging or digital subtraction angiography. Dissection score was developed from associated factors to discriminate VA occlusive dissection by logistic regression analysis. Discriminative performance was analyzed by receiver operating curve (ROC) analysis. Results: Consecutive 84 patients (70±13 years; male, 77%) involved 16 (19%) with VA occlusive dissection. On logistic regression analysis, each of younger age ( ≤ 70 years), absence of hypertension, absence of dyslipidemia, head or neck pain, medullary infarction and non-dominance side VA occlusion were significantly associated with VA occlusive dissection (Table). Dissection score was created with these factors by assigning respective points based on the corresponding regression coefficients, and the score were ranged from 0 to 9 (Table). High discriminative performance for VA occlusive dissection was observed (area under the curve: 0.91) and optimal cut-off value was 5 or more (accuracy, 79%; sensitivity, 94%; specificity, 75%). Conclusions: In patients with acute posterior ischemic stroke due to unilateral VA occlusion, dissection score had high discriminative performance for diagnosing VA dissection.

Cervical Spinal Cord Infarction Presenting as Chest Pain in Patients with Acute Cerebellar Infarction

Spinal cord infarction is rare, especially cervical cord infarction is lesser than thoracic and lumbar level. We describe two cases of cervical cord infarction following cerebellar infarction with vertebral artery occlusion, which initially presented with chest pain and dyspnea. Blood supply for the cervical cord comes from anterior and posterior spinal artery, which originated from the distal vertebral or posterior inferior cerebellar arteries. Therefore, occlusion of unilateral vertebral artery could cause a cervical cord infarction.

Correlation between the hemodynamic parameters of extracranial vertebral artery and the severity and location of intracranial vertebral artery stenosis

Objective To analyze the effects of the degree and location of intracranial vertebral artery(VA) lesions on the hemodynamic parameters of extracranial VA. Methods A total of 275 consecutive patients who were diagnosed as posterior circulation ischemic stroke or transient ischemic attack (TIA) with unilateral intracranial VA stenosis or occlusion in the Department of Neurology and Neurosurgery of Capital Medical University Xuanwu Hospital from January 2015 to December 2017 were enrolled. All patients were examined by head and neck vascular ultrasound, CT angiography (CTA) and/or digital subtraction angiography (DSA) within one week. According to the results of DSA or CTA, the patients were divided into mild stenosis group(53 patients), moderate stenosis group(62 patients), severe stenosis group(58 patients) and occlusion group(102 patients). The inner diameter (D), peak systolic velocity (PSV), end diastolic velocity (EDV), and resistance index (RI) of the extracranial segment (V2 segment) of the VA were recorded and analyzed. Results The PSV and EDV in the severe stenosis group and the occlusion group were significantly lower than those in the mild stenosis group and the moderate stenosis group (P=0.000), and the PSV and EDV in the occlusion group were significantly lower than those in the severe stenosis group[ (31±10) cm/s vs (46±12)cm/s, (5±4)cm/s vs (15±7)cm/s; all P=0.000], RI was significantly higher than the other three groups (0.85±0.12, 0.70±0.10, 0.66±0.07, 0.64±0.06, respectively; all P=0.000); RI in the severe stenosis group were not significantly different from those in the mild to moderate stenosis groups (P=0.044, 0.223). There were no significant differences in the inner diameter, PSV, EDV and RI between the subgroups in the severe stenosis group before or after the PICA (posterior inferior cerebellar artery)(P=0.130, 0.322, 0.865, 0.227). However, the EDV decreased and RI increased in the occlusive subgroup before the PICA when compared the subgroup after the PICA (all P=0.000). Conclusions The location and degree of intracranial VA lesions directly affect the changes of blood flow velocity and vascular resistance of extracranial VA, and the changes of low-speed and high-resistance hemodynamics of extracranial VA may indicate the existence of occlusive lesions in intracranial VA. Key words: Ultrasonography; Vertebral artery stenosis; Occlusive diseases; Hemodynamics; Extracranial segment; Intracranial segment

P107. Releasing anterior soft tissue and reduction of the irreducible atlantoaxial dislocation associated with basilar invagination through single-stage posterior approach

BACKGROUND CONTEXT The management of AAD combined with BI is challenging. Traditional posterior approaches lack the ability to release the anterior soft tissue and result in unsatisfactory reduction; posterior fixation followed by the anterior release approach has higher morbidity and lead to higher costs and a longer length of stay. PURPOSE This study aims to analyze outcomes of the release of anterior soft tissue through posterior route in order to reduce irreducible atlantoaxial dislocation (AAD) and basilar invagination (BI) through a single-stage operation. This study aims to analyze outcomes of the release of anterior soft tissue through posterior route in order to reduce irreducible atlantoaxial dislocation (AAD) and basilar invagination (BI) through a single-stage operation. STUDY DESIGN/SETTING This is a retrospective study. PATIENT SAMPLE Thirty-one patients with irreducible AAD and concomitant BI with congenital osseous abnormalities were analyzed. OUTCOME MEASURES The clinical results were evaluated using the Japanese Orthopedic Association (JOA) scale, and the radiological measurements included anterior atlantodental interval (ADI), the distance of odontoid tip above Chamberlain line, clivus-canal angle (CCA) and the length of the syrinx. METHODS The anterior soft tissue was released posteriorly, and cages were placed into the facet joint followed by occipital-cervical fixation with cantilever correction. We used paired t-test to compare preoperative and postoperative measurements. RESULTS The mean JOA score increased from 11.65 to 14.48 at 1-year follow-up. Complete reduction of AAD and BI was achieved in 23 patients (74.2%). The mean clivus-canal angle improved from 113.0 degrees preoperatively to 148.4 degrees postoperatively. Shrinkage of the syrinx was observed in 6 patients in one week after surgery. Nine patients had 18-month follow-up and achieved bone fusion. Twenty-two patients have a 12-month follow-up, and 19 (86.3%) achieved bony fusion. Unilateral vertebral artery occlusion was diagnosed in 2 cases without clinical symptoms. CONCLUSIONS It appears effective and safe to treat irreducible AAD associated with BI by releasing the anterior soft tissue from a posterior approach. Cage implantation within the facet and fixation using cantilever can achieve complete reduction in most cases. FDA DEVICE/DRUG STATUS This abstract does not discuss or include any applicable devices or drugs.

Awareness of traumatic occult lateral mass fracture of the cervical spine triggered by the presence of unilateral vertebral artery occlusion: a case report.

We present an unusual case of traumatic occult lateral mass fracture of the cervical spine with unilateral occlusion of the vertebral artery (VA), that was missed by plain X-ray and magnetic resonance imaging (MRI), but identified by computed tomography (CT) after suspecting high-energy trauma as the underlying cause. A 67-year-old male was injured in a car accident and came to our institute on foot 4 days after injury with complaints of neck pain and numbness in the right hand. Although, no specific bone injury was visible on plain X-ray, the absence of flow voids in the right VA was confirmed on axial T2-weighted MRI. We suspected high-energy trauma of the cervical spine at that point and performed CT for a more detailed assessment. Consequently, a fracture was detected in the right lateral mass of C6 and we speculated that spontaneous reduction of the fracture-dislocation had occurred. One-stage surgery with posterior fixation was subsequently performed for instability. The patient's preoperative symptoms were improved and neither recanalization of the occlusion nor another VA occlusion was observed after surgery. VA injury occurs frequently as a complication of blunt cervical spine trauma. In the present case, however, the lateral mass fracture was not seen on MRI and missed until the unilateral VA injury was detected. When high-energy trauma of the cervical spine is suspected, it is important to evaluate damage to the spinal cord, bone, soft-tissue, and VA by MRI and CT.

Two-stage corrective surgery for severe rigid cervical kyphotic deformity with unilateral vertebral artery occlusion after old blunt trauma: a case report.

There are considerable risks for vertebral artery (VA) injury in case of corrective surgery for a severe and rigid cervical kyphotic deformity. This case report describes a rare case of surgical management for pre-existing traumatic rigid cervical kyphosis associated with unilateral VA occlusion. A 73-year-old male fell down and injured his neck. He was referred to our hospital 10 months after injury because his degree of head drop progressed gradually to a chin-on-chest position such that he could not look straight forward. On plain X-ray, the C2-7 angles in the neutral, flexion, and extension positions were 61°, 71°, and 50°, respectively. CT revealed a collapse of the C5 vertebral body and bone fusion between C4 and C5 in the anterior vertebrae, and unilateral VA occlusion was confirmed by angiography. Two-stage surgery was planned to correct the kyphosis. In the first stage, anterior release of the C4/5 bone-spur fusion and dissection of the intervertebral disk were performed. After release, angiography confirmed neither occlusion nor rupture of the VA. In the second stage, anterior and posterior fixation was performed at correcting position while maintaining slight kyphosis in order to avoid excessive distortion of the VA. The postoperative C2-7 kyphosis angle improved to 16° without any VA injury, and the patient could look forward easily. The degree of correction as well as risk management of VAs should be considered carefully during corrective surgery for severe and rigid cervical kyphosis, especially with unilateral VA occlusion.

Management strategy for bilateral complex vertebral artery aneurysms.

Bilateral complex vertebral artery aneurysms (BCoVAAns) have no established strategy of management. We retrospectively reviewed five consecutive patients with unruptured BCoVAAns between January 2006 and December 2012. Considering surgical risks of lower cranial nerve (LCN) injuries and eventual growth of an opposite side lesion after unilateral vertebral artery (VA) occlusion, we proposed a strategy of combined open and interventional treatment using revascularization. We applied the following several specific techniques: (1) proximal clipping and occipital artery-posterior inferior cerebellar artery (OA-PICA) and/or superficial temporary artery (STA)-superior cerebellar artery (SCA) bypasses; (2) Distal blood pressure, motor evoked potentials (MEPs), and somatosensory evoked potentials (SEPs) monitoring after parent artery temporary occlusion for safe permanent occlusion of the proximal portions of VA and PICA; (3) V3 to V4 bypass using radial artery (RA) graft with proximal clipping or trapping, two of them combined with OA-PICA bypass; (4) VA fenestration as an opportunity to preserve the flow of the parent artery. Two patients were treated bilaterally and 3 unilaterally, with modified Rankin scale assessed at 39 months postoperatively in average 0 in 2, 1 in 2, and 2 in 1, respectively, and the untreated opposite side lesions without regrowth or bleeding. Two patients with patent V3-RA-V4 bypass complained of dysphagia due to LCN palsies. One of them however suffered a cerebellar infarction due to occlusion of the OA-PICA bypass. When BCoVAAns require surgical treatment, revascularization or preservation of the VA should be considered at the first operation. By doing so, the opposite aneurysm can be effectively occluded by coil embolization, even with VA sacrifice if required.

Anterior spinal artery as a collateral pathway in a case of unilateral vertebrobasilar occlusion: A case report and literature review

Background: Vertebral artery (VA) occlusion is an important cause of stroke in the posterior circulation along with basilar artery occlusion. Intracranial VA disease accounts for 21% of patients with posterior circulation stroke and is bilateral in nearly half of them. Anterior Spinal Artery (ASA) originating from cervical VA to intracranial distal VA and Basilar artery is a possible and infrequent source of collaterals. Case description: We report a case of acute unilateral vertebral artery occlusion with retrograde flow from ASA as the only collateral pathway reconstituting distal circulation. Conclusion: Anterior Spinal Artery can play an important role in the setting of unilateral or bilateral vertebral occlusion. Retrograde flow through ASA could reconstitute distal circulation. Adequacy of flow and neurological improvement in this situation depends on the presence of other collateral channels, other vertebral artery and on patency of vertebrobasilar junction.

Vertebral artery stenosis in the Basilar Artery International Cooperation Study (BASICS): prevalence and outcome.

We assessed the prevalence of vertebral artery (VA) stenosis or occlusion and its influence on outcome in patients with acute basilar artery occlusion (BAO). We studied 141 patients with acute BAO enrolled in the Basilar Artery International Cooperation Study (BASICS) registry of whom baseline CT angiography (CTA) of the intracranial VAs was available. In 72 patients an additional CTA of the extracranial VAs was available. Adjusted risk ratios (aRRs) for death and poor outcome, defined as a modified Rankin Scale score ≥4, were calculated with Poisson regression in relation to VA occlusion, VA occlusion or stenosis ≥50%, and bilateral VA occlusion. Sixty-six of 141 (47%) patients had uni- or bilateral intracranial VA occlusion or stenosis ≥50%. Of the 72 patients with intra- and extracranial CTA, 46 (64%) had uni- or bilateral VA occlusion or stenosis ≥50% and 9 (12%) had bilateral VA occlusion. Overall, VA occlusion or stenosis ≥50% was not associated with the risk of poor outcome. Patients with intra- and extracranial CTA and bilateral VA occlusion had a higher risk of poor outcome than patients without bilateral VA occlusion (aRR, 1.23; 95% CI 1.02-1.50). The risk of death did not depend on the presence of unilateral or bilateral VA occlusion or stenosis ≥50%. In conclusion, in patients with acute BAO, unilateral VA occlusion or stenosis ≥50% is frequent, but not associated with an increased risk of poor outcome or death. Patients with BAO and bilateral VA occlusion have a slightly increased risk of poor outcome.

Safety of Unilateral Endovascular Occlusion of the Cervical Segment of the Vertebral Artery without Antecedent Balloon Test Occlusion

Antecedent balloon test occlusion is often performed prior to vertebral artery sacrifice, but there is limited data to suggest this adds a significant clinical benefit, especially in the setting of trauma. Furthermore, balloon test occlusion can be time-consuming, add to the technical complexity of the procedure, and increase the overall cost of treatment. The purpose of this study was to determine the safety of unilateral vertebral artery occlusion without antecedent balloon test occlusion as part of the treatment regimen in patients with traumatic vertebral artery dissection, cervical tumor, or intracranial aneurysm. The medical records and imaging studies of 59 patients in whom unilateral endovascular cervical vertebral artery occlusion was performed were retrospectively reviewed. Procedure-related stroke was defined as imaging evidence of acute infarct in the vascular territories supplied by the occluded vertebral artery or new focal neurologic deficit developing in the first 30 days after vertebral artery occlusion attributable to infarction in the posterior circulation. Fifty-nine patients underwent unilateral endovascular cervical vertebral artery occlusion to prevent potential thromboembolic complications of vertebral artery injury, for treatment of intracranial aneurysms, or for presurgical embolization of a cervical vertebral tumor. Unilateral occlusion was performed when endovascular reconstruction was considered impossible or deemed more risky than deconstruction. Fifty-eight of the 59 patients underwent vertebral artery occlusion without antecedent balloon test occlusion. None of the 59 patients had clinical or imaging evidence of a postprocedural infarct. In this series, endovascular occlusion of a cervical segment of 1 vertebral artery was safely performed without antecedent balloon test occlusion. As long as both vertebral arteries were patent and converged at the vertebrobasilar junction, there was anatomic potential for retrograde filling of the distal intracranial vertebral artery to the level of the posterior inferior cerebellar artery origin, and there was no major vascular supply to the spinal cord arising from the target segment of the affected vessel. Dominant and nondominant vertebral arteries were safely occluded, and no infarcts were attributed to the treatment.

Hemodynamic stroke: A rare pitfall in cranio cervical junction surgery.

Surgical C1C2-stabilization may be complicated by arterial-arterial embolism or arterial injury. Another potential complication is hemodynamic stroke. The latter might be induced in patients with poor posterior fossa collateralization (risk factor 1) when the vertebral artery (VA) is compressed during reduction (risk factor 2). We report a clinical case where this rare situation occurred: A 72-year old patient was undergoing C1C2-stabilization for subluxation due to rheumatoid arthritis. Preoperative computed tomography angiography (CTA) had shown poor collaterals in the posterior fossa. Furthermore, intraoperative Doppler ultrasound (US) detected unilateral VA occlusion during reduction. It appeared to be a high-risk situation for hemodynamic stroke. Surgical inspection of the VA found osteofibrous compressing elements. Arterial decompression was performed resulting in the normal flow as detected by US. Subsequently, C1C2-stabilization could be realized. The clinical and radiological outcome was very favorable. In C1C2-stabilization precise analysis of preoperative CTA and intraoperative US are important to detect risk factors of hemodynamic stroke. Using these data may prevent this rare, but potentially life-threatening complication.

Traumatic, high-cervical, coronal-plane spondyloptosis with unilateral vertebral artery occlusion: treatment using a prophylactic arterial bypass graft, open reduction, and instrumented segmental fusion

The authors present a case of traumatic, complete, high cervical spine injury in a patient with gradual worsening deformity and neck pain while in rigid cervical collar immobilization, ultimately resulting in coronal-plane spondyloptosis. Due to the extent of lateral displacement of the spinal elements, preoperative evaluation included catheter angiography, which revealed complete right vertebral artery (VA) occlusion. A prophylactic arterial bypass graft from the right occipital artery to the extradural right VA was fashioned to augment posterior circulation blood supply prior to reduction and circumferential instrumented fusion. Following surgery, the patient was able to participate in an aggressive rehabilitation program allowing early mobilization, and he ceased to be ventilator-dependent following implantation of a diaphragmatic pacer. The authors review factors leading to progression of this type of injury and suggest technical pearls as well as highlight specific management pitfalls, including operative risks.

Evaluation of very early recanalization after tPA administration monitoring by transcranial color-coded sonography

Summary Background/aims Cerebrovascular ultrasonography was useful clinically for evaluating cerebral hemodynamics rapidly and in real-time for patients with acute ischemic stroke. We analyzed if the patients had early recanalization or not using transcranial color-coded sonography (TCCS) in order to evaluate the usefulness of real-time monitoring in systemic thrombolysis. Methods Subjects were patients who had acute ischemic stroke with intravenous tissue plasminogen activator (tPA) within 3 h from onset. We evaluated occlusion of intracranial arteries from transtemporal or suboccipital window by TC-CFI with Thrombolysis in Brain Ischemia (TIBI) flow-grading system and monitored residual flow in real-time every 15 min until 120 min after the t-PA bolus. Results We could monitor residual flow in 5 patients who had good echo windows (4 male, mean age; 60.8 ± 6.4 years). Two patients had proximal occlusion of the middle cerebral artery (MCA), one patient had distal occlusion of MCA, one patient had M2 occlusion and one patient had distal occlusion of unilateral vertebral artery. Four patients had early complete recanalization within 60 min after the t-PA bolus (two patients within 60 min and other two patients within 30 min), however, occlusion persisted during 120 min monitoring in one patient with proximal occlusion of MCA. NIH Stroke Scale of two patients with very early recanalization was 0 at the end of the treatment. There was no symptomatic and asymptomatic intracranial hemorrhage in 4 patients except for the patients without recanalization. Conclusions It is anticipated that real-time ultrasound monitoring is useful for evaluating a very early thrombolytic effect of tPA connected with early clinical recovery.

A rare complication of a unilateral vertebral artery occlusion, which resulted in a basilar emboli after a C5–C6 bifacet dislocation in a professional rugby player: case study

Background Vertebral artery damage after cervical fracture and especially cervical dislocations is a recognized phenomenon. The incidence of significant intracranial neurology after unilateral vertebral damage is extremely rare, and to our knowledge, no such injury has been sustained while playing sport. Purpose To describe a rare vascular complication of a bifacet C5–C6 dislocation. Study Design Case report and clinical discussion. Methods We present a 28-year old white man who was a professional rugby player. He sustained a hyperflexion injury while playing scrum half in a recent league match, which resulted in a C5–C6 dislocation, diagnosed clinically and with a plain radiograph. The patient on admission had complete neurologic loss below C6. Results The patient underwent immediate computed tomography and magnetic resonance imaging (MRI) scans that revealed a 50% displacement of C5 on C6 with a complete unifacet dislocation and the other facet partially dislocated. The MRI revealed signal changes in the cord at the C5–C6 level and an intimal tear in the left vertebral artery. The decision was taken to reduce the dislocation when medically stable. A few hours after injury, after an episode of vomiting, the patient sustained a respiratory arrest owing to the embolization of a clot from the left vertebral artery into the basilar artery. Despite rapid embolectomy and subsequent permanent left vertebral artery occlusion, the patient sustained multiple infarcts in the cerebellar, thalamic, occipital, and pontine regions of the brain that eventually proved fatal. Conclusion This case shows a rare complication of unilateral vertebral artery occlusion. Despite early identification of a basilar infarct and a successful embolectomy, intracranial infarction occurred. Although there is no guideline for the treatment of vertebral artery damage, early reduction and anticoagulation may reduce the risk of cerebral infarction.

Incidence of unilateral distal vertebral artery aplasia: evaluation by combining basiparallel anatomic scanning-magnetic resonance imaging (BPAS-MRI) and magnetic resonance angiography

The incidence of a unilateral aplastic distal vertebral artery (VA) has been reported as 0.2% of cases on cerebral angiography. During our daily magnetic resonance (MR) examinations, however, we frequently encounter MR angiograms (MRAs) that do not demonstrate unilateral VA. The purpose of this study was to calculate the frequency of aplastic unilateral distal VA by MR images performed for asymptomatic people. Over a time span of 1 year, 237 asymptomatic people (140 men, 97 women; ages 28-67 years, mean 54.4 years) underwent brain MRI during a "brain check-up examination" in our hospital. To identify an aplastic unilateral distal VA, we retrospectively compared three-dimensional time-of-flight MRA with basiparallel anatomic scanning (BPAS)-MRI which was designed for recognition of the arterial outer contour. Aplasia of the unilateral distal VA was confirmed in 11 persons (4.6%). According to our classification, hypoplastic distal VA in 12 (5.1%) and asymptomatic acquired unilateral distal VA occlusion was also proved in 2 (0.8%). We found that the frequency of aplastic unilateral VA was 4.6% in asymptomatic people using a combination of MRA and BPAS-MRI for assessment of an intracranial VA.