Longitudinal Pulse-Synchronous Bouncing During Catheter Angiography-A Phenomenon Specific to Spinal Hemangioblastomas.

BACKGROUND: Spinal hemangioblastomas are often evaluated with catheter angiography for both workup and treatment planning. We report a unique longitudinal pulse-synchronous bouncing phenomenon observed during their angiographic evaluation and consider the association of pulse-synchronous bouncing with syringomyelia, another pathologic feature associated with hemangioblastomas. METHODS: Preoperative spinal angiograms and associated magnetic resonance imagings (MRIs) obtained over a 16-year period at a single institution were retrospectively evaluated. Magnetic resonance imaging (MRI) parameters included lesion and syrinx location and size. Angiograms were evaluated for bouncing phenomena. Student's t-test and Chi square test compared characteristics between groups. Linear regression analyses evaluated maximum amplitude of dynamic motion and any associated syrinx. RESULTS: Nineteen hemangioblastoma patients had preoperative angiograms available for review. Eight exhibited bouncing behavior. Between the dynamic and nondynamic cohorts, there was no difference in presence or volume of syrinxes. Lesions in the dynamic cohort trended towards a cervical location (75% vs. 36.3%, P = 0.10). No significant correlation was found between bouncing amplitude and syrinx size (R2 = 0.023). Dural contact may be related to this dynamic behavior since other high-flow lesions like AVMs do not demonstrate this phenomenon, and AVMs are pial-based and more likely to contact stationary dura. Here, there were fewer lesions abutting the thecal sac in the dynamic cohort (50% vs. 81.8%, P = 0.14). CONCLUSIONS: Though no significant relationship was established between this bouncing behavior and syrinx formation, noted trends included a greater range of motion for cervical lesions and limited motion in tumors abutting the thecal sac.

Clinically Asymptomatic Hemorrhagic Conversion Is Associated with Need for Inpatient Rehabilitation After Mechanical Thrombectomy for Anterior Circulation Ischemic Stroke.

BACKGROUND: Hemorrhagic conversion (HC) is a known complication after acute ischemic stroke (AIS) in patients undergoing mechanical thrombectomy (MT). Although symptomatic HC has been shown to lead to poor neurologic outcomes, the effect of asymptomatic HC (aHC) is unclear. This study aims to identify predictors of aHC and to determine the short-term outcomes. METHODS: This is a single-institution retrospective study of patients with anterior circulation stroke (AIS) who underwent MT between January 2016 and September 2022. Radiographic HC was identified on postoperative imaging. Asymptomatic hemorrhage was defined as no acute neurologic decline attributable to imaging findings. Baseline characteristics, technical aspects, and outcomes were compared between aHC and no-HC groups. Logistic regression and multivariate analysis were performed. RESULTS: A total of 615 patients underwent MT for AIS, of whom 496 met the inclusion criteria. A total of 235 patients (47.4%) had evidence of aHC. Diabetes mellitus (odds ratio [OR], 1.59; 95% confidence interval [CI], 1.06-2.41; P = 0.03), hyperglycemia (OR, 1.01; 95% CI, 1.00-1.01; P = 0.002), greater number of passes (OR, 1.14; 95% CI, 1.00-1.31; P = 0.05), and longer time to reperfusion (OR, 1.02; 95% CI, 1.00-1.05; P = 0.05) were associated with aHC. Patients with aHC were significantly more likely to require rehabilitation, whereas those without HC were more likely to be discharged home (P < 0.001). There were no significant differences in long-term outcomes. CONCLUSIONS: HC occurred in up to half of patients who underwent MT for AIS, most of whom were clinically asymptomatic. Despite clinical stability, aHC was significantly associated with a greater need for inpatient rehabilitation. Predictors of aHC included hyperglycemia and a longer time to reperfusion.

Cervical anterior spinal artery infarction associated with anomalous vertebral artery: a case report.

We report a unique case of cervical anterior spinal artery (ASA) infarction in a 49-year-old male with hypercholesterolemia and sleep apnea. The patient experienced sudden cervical pain, quadriparesis, areflexia, and urinary incontinence after swallowing a large food bolus. Imaging revealed an infarction at the C3-C5 levels and an anomalous right vertebral artery (VA) originating from the thoracic aorta, tightly enclosed between the aorta and a vertebral column with an anterior osteophyte. This aberrant VA was the primary vascular supply to the ASA, with no contribution from the left VA or supreme intercostal arteries. We propose that transient injury to the right VA, induced by compression between the aortic arch, the food bolus, and the osteophyte, led to temporary hypoperfusion of the ASA, causing a watershed ischemic injury in the mid cervical cord's anterior gray matter. The article also provides an in-depth discussion of the developmental and clinical characteristics associated with this rare vascular anomaly.

Two pediatric observations of spinal extradural arteriovenous fistulas presenting with epidural hemorrhages and cord compression.

We report two cases of acute spinal cord compression in children with low-flow spinal epidural arteriovenous fistulas (SEAVFs) and discuss the clinical presentation and management of these vascular anomalies. While most low-flow SEAVFs without radiculomedullary drainage are benign lesions typically diagnosed incidentally, we suggest that asymptomatic lesions may warrant aggressive management in specific circumstances, including lesions diagnosed at an early age or in patients under anticoagulation therapy. Our observations also emphasize that patients with a "spontaneous" epidural hemorrhage should undergo dedicated preoperative or postoperative vascular imaging to identify a possible underlying vascular anomaly.

Bilateral Dilated Superior Ophthalmic Veins in a Patient With an Arteriovenous Dialysis Fistula.

A 64-year-old man presented with 4 months of diplopia. He had end-stage renal disease requiring a cephalic transposition brachiocephalic fistula that was no longer in use following successful renal transplantation. On presentation, he had bilateral proptosis, extraocular movement restriction, chemosis, tortuous episcleral vessels, and caruncular injection. Non-contrast CT of the orbits demonstrated dilation of both superior ophthalmic veins, and CT angiography showed asymmetric enlargement of both cavernous sinuses and superior ophthalmic veins. A carotid-cavernous fistula was suspected, but cerebral angiography revealed shunting from the old fistula with intracranial drainage and cerebral venous hypertension. Aberrant retrograde drainage resulted from anatomical compression of the left brachiocephalic vein. The fistula was ligated, and at 1-week follow-up, the patient had marked improvement in extraocular movements and orbital congestion with near complete resolution of diplopia. Postoperative CT angiography obtained 2 months later demonstrated decreased size of both superior ophthalmic veins, consistent with improvement of venous hypertension.

Racial disparities in functional outcomes following mechanical thrombectomy in a cohort of patients with ischemic stroke.

BACKGROUND: Non-Hispanic Black (NHB) patients experience increased prevalence of stroke risk factors and stroke incidence compared with non-Hispanic White (NHW) patients. However, little is known about >90-day post-stroke functional outcomes following mechanical thrombectomy. OBJECTIVE: To describe patient characteristics, evaluate stroke risk factors, and analyze the adjusted impact of race on long-term functional outcomes to better identify and limit sources of disparity in post-stroke care. METHODS: We retrospectively reviewed 326 patients with ischemic stroke who underwent thrombectomy at two centers between 2019 and 2022. Race was self-reported as NHB, NHW, or non-Hispanic Other. Stroke risk factors, insurance status, procedural parameters, and post-stroke functional outcomes were collected. Good outcomes were defined as modified Rankin Scale score ≤2 and/or discharge disposition to home/self-care. To assess the impact of race on outcomes at 3-, 6-, and 12-months' follow-up, we performed univariate and multivariate logistic regression. RESULTS: Patients self-identified as NHB (42%), NHW (53%), or Other (5%). 177 (54.3%) patients were female; the median (IQR) age was 67.5 (59-77) years. The median (IQR) National Institutes of Health Stroke Scale score was 15 (10-20). On univariate analysis, NHB patients were more likely to have poor short- and long-term functional outcomes, which persisted on multivariate analysis as significant at 3 and 6 months but not at 12 months (3 months: OR=2.115, P=0.04; 6 months: OR=2.423, P=0.048; 12 months: OR=2.187, P=0.15). NHB patients were also more likely to be discharged to rehabilitation or hospice/death than NHW patients after adjusting for confounders (OR=1.940, P=0.04). CONCLUSIONS: NHB patients undergoing thrombectomy for ischemic stroke experience worse 3- and 6-month functional outcomes than NHW patients after adjusting for confounders. Interestingly, this disparity was not detected at 12 months. Future research should focus on identifying social determinants in the short-term post-stroke recovery period to improve parity in stroke care.

Classification and Management Considerations for Intraosseous Dural Arteriovenous Fistulae.

BACKGROUND: Intraosseous dural arteriovenous fistulas (IODAVFs) are rare DAVFs that communicate with marrow. Given their infrequency, common nomenclature is nonexistent. Patients may present with benign symptoms, such as tinnitus, or venous hypertension symptoms including hemorrhage depending on the venous outflow pattern. OBJECTIVE: To describe all available cases of IODAVF in the literature, in addition to our cases, to better define presentation, and treatment outcomes. To advance a classification system to develop common language for these lesions for clinicians and researchers. METHODS: Neurointerventional procedure logs at 2 high-volume neurovascular centers were reviewed for all cases of IODAVFs, as was the English-based literature available in PubMed. The angioarchitecture, symptoms, management, and demographics were reviewed and summarized. RESULTS: Four institutional cases were identified, 2 of which had shunting within the marrow (clival or petrous), with venous drainage toward the heart. One case involved the dorsum sella with drainage into the superior petrosal sinus with reflux into the anterior and posterior spinal venous plexuses, and one involved the left petroclival junction, resulting in communication with the cavernous sinus with retrograde drainage into the superior ophthalmic veins. Two patients were managed by observation, one was treated with radiosurgery and one with microsurgical skeletonization. Twenty additional cases from the literature are summarized. CONCLUSION: IODAVFs of the cerebrocranial vasculature may present incidentally, with tinnitus, or with symptoms related to mass effect or venous hypertension. We propose a classification which accounts for drainage patterns. Further study is needed for these rare lesions.

Tracheobronchial arterial variants of vertebral artery origin and bronchovertebral arterial anastomoses.

PURPOSE: This report describes a series of angiographic observations of tracheobronchial arterial variants and discusses their clinical implications. METHODS: The angiographic features of eleven aberrant tracheal or bronchial arteries are reported, including four variants originating from the vertebral artery and two cases of bronchovertebral anastomosis. An additional observation of thyrothymic artery illustrates the discussion of the mechanisms involved in the development of these variants. RESULTS: Tracheobronchial arterial variants are predominantly left-sided variants (9 out of 11). They are linked to dominant paratracheal arterial connections, particularly the lateral longitudinal anastomosis. Unusual bronchial arteries of vertebral origin show a strong association with aberrant left vertebral arteries of aortic or proximal subclavian origin. CONCLUSION: This report presents a spectrum of tracheo-broncho-vertebral variations and emphasizes the role of previously described paratracheal arterial anastomoses in their formation. These variants can play a critical role during hemoptysis embolotherapy, either as an occult source of hemorrhage or as a risk factor for devastating complications.

The segmentation of the vertebral artery: An ambiguous anatomical concept.

The course of the vertebral artery from its subclavian artery origin up to its termination at the vertebrobasilar junction is divided into four segments (V1-V4). This segmentation, based on schemes that have evolved since the late nineteenth century, should be a consistent and reproducible anatomical concept. However, the current literature offers conflicting definitions of that scheme, not infrequently within a single article or monograph. The principal inconsistency found in modern publications concerns the termination of the V2 segment, which is either set at the C2 or C1 transverse foramen depending on the scheme considered. Consequently, the portion of the vertebral artery extending between C2 and C1-a frequent site of pathological involvement-either belongs to the V2 or V3 segment. This discrepancy can affect the validity of studies evaluating the diagnosis and management of vertebral artery disorders. A V3 segment extending from the transverse foramen of C2 to the posterior atlanto-occipital membrane and subdivided into vertical, horizontal, and oblique subsegments-a pattern suggested by Barbieri in 1867 and adopted in some modern publications-would provide a simple, precise, and reliable solution without significantly altering the widely accepted division of the vertebral artery into four segments (V1-V4).

Epidemiology and outcomes of pediatric intracranial aneurysms: comparison with an adult population in a 30-year, prospective database.

OBJECTIVE: Pediatric intracranial aneurysms are rare. Most large series in the last 15 years reported on an average of only 39 patients. The authors sought to report their institutional experience with pediatric intracranial aneurysms from 1991 to 2021 and to compare pediatric patient and aneurysm characteristics with those of a contemporaneous adult cohort. METHODS: Pediatric (≤ 18 years of age) and adult patients with one or more intracranial aneurysms were identified in a prospective database. Standard epidemiological features and outcomes of each pediatric patient were retrospectively recorded. These results were compared with those of adult aneurysm patients managed at a single institution over the same time period. RESULTS: From a total of 4500 patients with 5150 intracranial aneurysms admitted over 30 years, there were 47 children with 53 aneurysms and 4453 adults with 5097 aneurysms; 53.2% of children and 36.4% of adults presented with a subarachnoid hemorrhage (SAH). Pediatric aneurysms were significantly more common in males, more likely giant (≥ 25 mm), and most frequently located in the middle cerebral artery. Overall, 85.1% of the pediatric patients had a modified Rankin Scale score ≤ 2 at the last follow-up (with a mean follow-up of 65.9 months), and the pediatric mortality rate was 10.6%; all 5 patients who died had an SAH. The recurrence rate of treated aneurysms was 6.7% (1/15) in the endovascular group but 0% (0/31) in the microsurgical group. No de novo aneurysms occurred in children (mean follow-up 5.5 years). CONCLUSIONS: Pediatric intracranial aneurysms are significantly different from adult aneurysms in terms of sex, presentation, location, size, and outcomes. Future prospective studies will better characterize long-term aneurysm recurrence, rebleeds, and de novo aneurysm occurrences. The authors currently favor microsurgical over endovascular treatment for pediatric aneurysms.

Endovascular therapy for acute stroke in children: age and size technical limitations.

Endovascular therapies for acute childhood stroke remain controversial and little evidence exists to determine the minimum age and size cut-off for thrombectomy in children. Despite this, an increasing number of reports suggest feasibility of thrombectomy in at least some children by experienced operators. When compared with adults, technical modifications may be necessary in children owing to differences in vessel sizes, tolerance of blood loss, safety of contrast and radiation exposure, and differing stroke etiologies. We review critical considerations for neurologists and neurointerventionalists when treating pediatric stroke with endovascular therapies. We discuss technical factors that may limit feasibility of endovascular therapy, including size of the femoral and cervicocerebral arteries, which contributes to vasospasm risk. The risk of femoral vasospasm can be assessed by comparing catheter outer diameter with estimated femoral artery size, which can be estimated based on the child's height. We review evidence supporting specific strategies to mitigate cervicocerebral arterial injury, including technique (stent retrieval vs direct aspiration) and device size selection. The importance of and strategies for minimizing blood loss, radiation exposure, and contrast administration are reviewed. Attention to these technical limitations is critical to delivering the safest possible care when thrombectomy is being considered for children with acute stroke.

Report of a spinal extradural arteriovenous fistula with double radiculomedullary venous drainage: therapeutic implications and role of intraoperative spinal angiography.

Low-flow spinal extradural arteriovenous fistulas (SEAVFs) are frequently misdiagnosed as spinal dural arteriovenous fistulas (SDAVFs), and their true prevalence is unknown. The principal feature distinguishing low-flow SEAVFs from SDAVFs is the location of the shunt, which involves a pouch of epidural plexus in SEAVFs and a radiculomedullary vein (RMV) in SDAVFs. A venous hypertensive myelopathy comparable to the one observed with SDAVFs develops when the arterialized venous pouch of an SEAVF is connected to an RMV. Depending on the size of the epidural pouch, a low-flow SEAVF may uncommonly drain into multiple RMVs. The authors present an observation of a low-flow SEAVF whose double radiculomedullary drainage was revealed only after intraoperative digital subtraction angiography, and they discuss the surgical implications of this anatomical configuration.

Mid-term assessment of transverse sinus stent patency in 104 patients treated for intracranial hypertension secondary to dural sinus stenosis.

BACKGROUND: Transverse sinus (TS) stenting is a valid treatment alternative for patients with intracranial hypertension caused by underlying bilateral TS stenoses. Its mid-term patency has, however, not been well documented. OBJECTIVE: To assess the 6-month patency of TS stenting using subtracted CT venography (CTV). METHODS: A retrospective analysis of a prospectively collected database of patients undergoing TS stenting was performed. The cohort was a single-center, single-operator series of 125 consecutive patients treated between 2008 and 2018. Mid-term follow-up 320-row detector CTV was available for review in 104 patients. RESULTS: Follow-up CTV was obtained on average 6 months after stenting. Stents in all patients (100%) were patent. Subtracted reconstructions showed no intraluminal thrombus or neointimal hyperplasia. Native reconstructions confirmed the structural integrity of the stents. De novo stenosis proximal to the stent was noted in 10 cases (10%). A total of 10 patients (10%) received additional treatment due to recurrent symptoms. In univariate analysis, both high body mass index and stent size (>6 mm) were associated with development of de novo stenoses: OR 1.12 (95% CI 1.01 to 1.25, p=0.037) and OR 5.63 (95% CI 1.16 to 27.22, p=0.032), respectively. In multivariate analysis, only stent size (>6 mm) remained significant: OR 7.19 (95% CI 1.03 to 50.01, p=0.046). CONCLUSION: TS stenting is an effective treatment for intracranial hypertension secondary to dural sinus stenosis in an appropriately selected patient population. A 320-row dynamic CTV is a high-quality non-invasive imaging method that can assess both the physical integrity of the stent and its patency. At mid-term follow-up, all imaged stents were patent. The occurrence of de novo stenoses proximal to the stent (10%) correlated with stent size (>6 mm).

Spinal fistulas documented by contrast enhanced computed tomography during myelopathy workup: a lost opportunity.

PURPOSE: Low-flow spinal arteriovenous fistulas (SAVFs) with intradural venous drainage typically manifest with a progressive venous hypertensive myelopathy (VHM) in older patients. VHM is difficult to identify. MRI is often nonspecific, and many cases are initially misdiagnosed, most often as transverse myelitis. The workup of myelopathic patients frequently includes thoracic and/or abdominal contrast-enhanced CT (CECT) that are generally not reviewed by neuroradiologists. The purpose of this work was to investigate how often abnormal enhancing intracanalar structures corresponding to the draining veins of a low-flow SAVF were documented by CECT. MATERIALS AND METHODS: We evaluated 92 consecutive patients with low-flow SAVFs and VHM treated at our institution between 2009 and 2018. The study group included 22 of these patients with at least one thoracoabdominal CECT available for review. The control group consisted of 20 consecutive myelopathy patients with negative angiography and at least one thoracoabdominal CECT. Intracanalar enhancing structures were classified either as (i) conspicuous or (ii) equivocal or absent. RESULTS: One CECT in the study group was technically inadequate. Conspicuous intracanalar enhancing structures were observed in 20 of the remaining 21 patients with SAVFs (95.2%) and in 2 of 20 control patients (10%). None of the enhancing intracanalar structures was mentioned in official study reports. CONCLUSIONS: The presence of enhancing vascular structures within the spinal canal on thoracoabdominal CECT obtained during the workup of myelopathies appears to represent a powerful but currently underappreciated tool for the detection of low-flow SAVFs.

Persistent second cervical intersegmental artery in a case of possible PHACE syndrome.

The proximal segment of the vertebral artery most often consists of a persistent sixth cervical intersegmental artery that originates from the subclavian artery, but it may also derive from a fifth, fourth, or third cervical intersegmental artery (in decreasing order of frequency), or from a first thoracic intersegmental artery. The involvement of more cranial cervical branches is exceptional, with no known persistent first cervical intersegmental artery and possibly five cases of persistent second cervical intersegmental arteries reported so far. This report describes a patient with multiple arterial variations including right persistent second cervical intersegmental artery of common carotid origin, distal VA duplication, circumflex aortic arch, and segmental internal carotid agenesis in a context of possible PHACE syndrome.

Spinal vascular malformations: Angiographic evaluation and endovascular management.

Spinal vascular malformations (SVM) are classified based on their location (intramedullary, perimedullary, radicular, extradural) and flow pattern (high-flow, low-flow, no arteriovenous shunt). High-flow SVMs are generally congenital lesions diagnosed in children and young patients without gender predominance. They present with hemodynamic disturbances, mass effect, or hemorrhages, but may also be discovered incidentally. Low-flow SVMs tend to be acquired lesions presenting in older men with progressive myelopathy caused by spinal venous hypertension. They are rarely associated with vascular syndromes but may accompany prothrombotic conditions. The sensitivity and specificity of conventional MRI are excellent for high-flow SVMs but poor for low-flow lesions, which are frequently diagnosed with extensive delays reducing the potential for favorable outcomes. The sensitivity of advanced MRI techniques remains unclear, notably for the detection of low-flow shunts without flow voids on conventional MRI. Catheter angiography remains the gold standard modality for the evaluation of the spinal vasculature and its disorders. SVMs can be treated by surgical or endovascular means. Initially plagued by high recurrence rates due to inadequate embolization material, endovascular techniques represent nowadays a valid alternative to surgery, thanks notably to the introduction of liquid embolic agents.

Neurovascular anatomy: Spine.

The arterial supply of the spinal cord is provided by the spinal branch of the cervical, thoracic, and lumbar intersegmental arteries. While supply is initially provided at each embryonic segment, only a few prominent anterior radiculomedullary arteries remain at the adult stage, including the arteries of the cervical and lumbosacral enlargements as well as a constant upper thoracic contributor. The spinal cord is surrounded by the vasocorona, an arterial network that includes several longitudinal anastomotic chains, notably the anterior and posterior spinal arteries, which respectively supply the central and peripheral components of the intrinsic vascularization. The intrinsic venous circulation is also divided into central and peripheral components. The perimedullary venous system includes several longitudinal anastomotic chains interconnected by the coronary plexus. The radiculomedullary veins loosely follow the spinal nerve roots on their way to the epidural plexus. Their point of passage through the thecal sac forms an important valve-like structure, the antireflux mechanism.