Microsurgical versus endovascular treatment of ethmoidal dural arteriovenous fistulas: systematic review and meta-analysis with a single-center case series.

OBJECTIVE: Ethmoidal dural arteriovenous fistulas (DAVFs) are often associated with cortical venous drainage (CVD) and a higher incidence of hemorrhage compared with DAVFs in other locations. They may be treated with open surgical disconnection or with endovascular treatment (EVT). In this systematic review and meta-analysis, the authors compare the outcomes of ethmoidal DAVFs treated with open microsurgery versus EVT and report four additional cases of ethmoidal DAVFs treated with open microsurgery in their institution. METHODS: A literature search of the PubMed and Scopus databases was conducted between December 2021 and May 2022 to identify relevant articles published between 1990 and 2021 using the PRISMA guidelines. References were reviewed and screened by two authors independently, and disagreements were resolved through consensus. Exclusion criteria included non-English-language studies, those with an incorrect study design, those reporting DAVFs in a nonethmoidal location, and studies whose outcomes were not stratified based on DAVF location. Inclusion criteria were any studies reporting on ethmoidal DAVFs treated by either microsurgery or EVT. A risk of bias assessment was performed using the Newcastle-Ottawa Scale. The authors performed a pooled proportional meta-analysis to compare patient outcomes. RESULTS: Twenty studies were included for analysis. Of 224 patients, 142 were treated with surgery, while 103 were treated with EVT. Seventy percent (148/210) of the patients were symptomatic at presentation, with hemorrhage being the most common presentation (48%). CVD was present in 98% of patients and venous ectasia in 61%. The rates of complete DAVF obliteration with surgery and EVT were 89% and 70%, respectively (95% CI -30% to -10%, p < 0.03). Twenty percent (21/103) of endovascularly treated fistulas required subsequent surgery. Procedure-related complications occurred in 10% of the surgical cases, compared with 13% of the EVT cases. The authors' case series included 4 patients with ethmoidal DAVFs treated surgically with complete obliteration, without any postoperative complications. CONCLUSIONS: The complete obliteration rates of ethmoidal DAVF appear to be higher and more definitive with microsurgical intervention than with EVT. While complication rates between the two procedures seem similar, patients treated with EVT may require further interventions for definitive treatment. The limitations of this study include its retrospective nature, the quality of studies included, and the continued evolving technologies of EVT. Future studies should focus on the association between venous drainage pattern and the proclivity toward venous ectasia or rate of hemorrhage at presentation.

Bilateral infraoptic origin of the anterior cerebral artery: illustrative case.

BACKGROUND: A bilateral infraoptic origin of the anterior cerebral arteries (ACAs) is a rare anatomical variant that can be encountered during anterior skull base surgery. The ACAs arise from the internal carotid artery (ICA) at the level of the ophthalmic artery and course medially, traveling inferior to the ipsilateral optic nerves. Herein, the authors discuss the different configurations of the anatomical variant, its prevalence, and hypotheses leading to the variable configuration of this anomaly. OBSERVATIONS: A 67-year-old woman presented with worsening dizziness over a week-long period and was found to have a large left sphenocavernous meningioma with optic, cavernous, and suprasellar extension. The tumor incorporated the left supraclinoid ICA and its branches. She underwent a left modified orbitozygomatic craniotomy for tumor resection. Early identification of the aberrant ACA anatomy was crucial in avoiding vascular injury. LESSONS: While this variant is typically encountered during the treatment of vascular pathologies-namely, intracranial aneurysms-its existence should be kept in mind during the treatment of any anterior skull base pathology. Failure to account for the presence of this variant may lead to potential intraoperative complications.

Seven bypasses simulation set: description and validity assessment of novel models for microneurosurgical training.

OBJECTIVE: Microsurgical training remains indispensable to master cerebrovascular bypass procedures, but simulation models for training that accurately replicate microanastomosis in narrow, deep-operating corridors are lacking. Seven simulation bypass scenarios were developed that included head models in various surgical positions with premade approaches, simulating the restrictions of the surgical corridors and hand positions for microvascular bypass training. This study describes these models and assesses their validity. METHODS: Simulation models were created using 3D printing of the skull with a designed craniotomy. Brain and external soft tissues were cast using a silicone molding technique from the clay-sculptured prototypes. The 7 simulation scenarios included: 1) temporal craniotomy for a superficial temporal artery (STA)-middle cerebral artery (MCA) bypass using the M4 branch of the MCA; 2) pterional craniotomy and transsylvian approach for STA-M2 bypass; 3) bifrontal craniotomy and interhemispheric approach for side-to-side bypass using the A3 branches of the anterior cerebral artery; 4) far lateral craniotomy and transcerebellomedullary approach for a posterior inferior cerebellar artery (PICA)-PICA bypass or 5) PICA reanastomosis; 6) orbitozygomatic craniotomy and transsylvian-subtemporal approach for a posterior cerebral artery bypass; and 7) extended retrosigmoid craniotomy and transcerebellopontine approach for an occipital artery-anterior inferior cerebellar artery bypass. Experienced neurosurgeons evaluated each model by practicing the aforementioned bypasses on the models. Face and content validities were assessed using the bypass participant survey. RESULTS: A workflow for model production was developed, and these models were used during microsurgical courses at 2 neurosurgical institutions. Each model is accompanied by a corresponding prototypical case and surgical video, creating a simulation scenario. Seven experienced cerebrovascular neurosurgeons practiced microvascular anastomoses on each of the models and completed surveys. They reported that actual anastomosis within a specific approach was well replicated by the models, and difficulty was comparable to that for real surgery, which confirms the face validity of the models. All experts stated that practice using these models may improve bypass technique, instrument handling, and surgical technique when applied to patients, confirming the content validity of the models. CONCLUSIONS: The 7 bypasses simulation set includes novel models that effectively simulate surgical scenarios of a bypass within distinct deep anatomical corridors, as well as hand and operator positions. These models use artificial materials, are reusable, and can be implemented for personal training and during microsurgical courses.

Neurosurgical management of patients with neurocutaneous melanosis: a systematic review.

OBJECTIVE: Neurocutaneous melanocytosis (NCM), also referred to as neurocutaneous melanosis, is a rare neurocutaneous disorder characterized by excess melanocytic proliferation in the skin, leptomeninges, and cranial parenchyma. NCM most often presents in pediatric patients within the first 2 years of life and is associated with high mortality due to proliferation of melanocytes in the brain. Prognosis is poor, as patients typically die within 3 years of symptom onset. Due to the rarity of NCM, there are no specific guidelines for management. The aims of this systematic review were to investigate approaches toward diagnosis and examine modern neurosurgical management of NCM. METHODS: A systematic review was performed using the PubMed database between April and December 2021 to identify relevant articles using PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. Search criteria were created and checked independently among the authors. Inclusion criteria specified unique studies and case reports of NCM patients in which relevant neurosurgical management was considered and/or applied. Exclusion criteria included studies that did not report associated neurological diagnoses and neuroimaging findings, clinical reports without novel observations, and those unavailable in the English language. All articles that met the study inclusion criteria were included and analyzed. RESULTS: A total of 26 extracted articles met inclusion criteria and were used for quantitative analysis, yielding a cumulative of 74 patients with NCM. These included 21 case reports, 1 case series, 2 retrospective cohort studies, 1 prospective cohort study, and 1 review. The mean patient age was 16.66 years (range 0.25-67 years), and most were male (76%). Seizures were the most frequently reported symptom (55%, 41/74 cases). Neurological diagnoses associated with NCM included epilepsy (45%, 33/74 cases), hydrocephalus (24%, 18/74 cases), Dandy-Walker malformation (24%, 18/74 cases), and primary CNS melanocytic tumors (23%, 17/74 cases). The most common surgical technique was CSF shunting (43%, 24/56 operations), with tethered cord release (4%, 2/56 operations) being the least frequently performed. CONCLUSIONS: Current management of NCM includes CSF shunting to reduce intracranial pressure, surgery, chemotherapy, radiotherapy, immunotherapy, and palliative care. Neurosurgical intervention can aid in the diagnosis of NCM through tissue biopsy and resection of lesions with surgical decompression. Further evidence is required to establish the clinical outcomes of this rare entity and to describe the diverse spectrum of intracranial and intraspinal abnormalities present.

In Vivo Preclinical Quantitative Flow Analysis of Arterial Anastomosis Using a Microvascular Anastomotic Coupler and Clinical Application for Extracranial-to-Intracranial Bypass.

OBJECTIVE: Although several commercially available sutureless anastomotic techniques are available, they are not routinely used in neurosurgery. We performed an in vivo flow analysis of end-to-end anastomosis using a microvascular coupler device in rats. We report our first clinical use of the microvascular anastomotic coupler. METHODS: Bilateral rat common carotid arteries (CCAs) were exposed, and a microvascular coupler was used to perform 8 anastomoses. A microflow probe provided quantitative measurement of blood-flow volume. Flow augmentation was assessed with end-to-side anastomoses connecting the distal CCA to the jugular vein (JV). A patient with chronic dominant hemisphere atherosclerotic ischemic disease and progressive symptoms refractory to medical management underwent end-to-end cerebral artery bypass using the microvascular coupler. RESULTS: Mean preanastomosis flow in the rat CCA was 3.95 ± 0.45 mL/min; this flow was maintained at 3.99 ± 0.24 mL/min on final measurements 54-96 minutes postanastomosis. Total occlusion time for each rat CCA was 12-19 minutes. After end-to-side anastomosis, with proximal and distal JV patent, CCA flow increased 477% to 22.8 ± 3.70 mL/min (P = 0.04, proximal; P = 0.01, distal). After in vivo testing, we successfully used the coupler clinically in a superficial temporal artery-to-middle cerebral artery bypass for dominant hemisphere flow augmentation. CONCLUSIONS: In vivo quantitative flow analysis demonstrated no flow difference between an unaltered artery and artery with end-to-end anastomosis using a microvascular coupler in rats. A 1-mm coupled anastomosis achieved a 4-fold flow increase with low-resistance venous outflow in rats, simulating increased arterial demand. The coupler was successfully used for extracranial-to-intracranial bypass in a patient.

Endovascular treatment of vertebral artery dissecting aneurysms : a 20-year institutional experience.

BACKGROUND: The ideal treatment for unruptured vertebral artery dissecting aneurysms (VADAs) and ruptured dominant VADAs remains controversial. We report our experience in the management and endovascular treatment of patients with VADAs. METHODS: Patients treated endovascularly for intradural VADAs at a single institution from January 1, 1999, to December 31, 2019, were retrospectively reviewed. Primary neurological outcomes were assessed using modified Rankin Scale (mRS) scores, with mRS >2 considered a poor neurological outcome. Additionally, any worsening (increase) in the mRS score from the preoperative neurological examination was considered a poor outcome. RESULTS: Ninety-one patients of mean (SD) age 53 (11.6) years (48 (53%) men) underwent endovascular treatment for VADAs. Fifty-four patients (59%) presented with ruptured VADAs and 44 VADAs (48%) involved the dominant vertebral artery. Forty-seven patients (51%) were treated with vessel sacrifice of the parent artery, 29 (32%) with flow diversion devices (FDDs), and 15 (17%) with stent-assisted coil embolization (stent/coil). Rates of procedural complications and retreatment were significantly higher with stent/coil treatment (complications 4/15; retreatment 6/15) than with vessel sacrifice (complications 1/47; retreatment 2/47) or FDD (complications 2/29; retreatment 4/29) (p=0.008 and p=0.002, respectively). Of 37 patients with unruptured VADAs treated, only two (5%) had mRS scores >2 on follow-up. CONCLUSION: Endovascular FDD treatment of VADAs appears to be associated with lower retreatment and complication rates than stenting/coiling, although further study is required for confirmation. Endovascular treatment of unruptured VADAs was safe and was associated with favorable angiographic and neurological outcomes.

Transradial cerebral angiography becomes more efficient than transfemoral angiography: lessons from 500 consecutive angiograms.

BACKGROUND: Transradial arterial access (TRA) for cerebral diagnostic angiography is associated with fewer access site complications than transfemoral access (TFA). However, concerns about increased procedure time and radiation exposure with TRA may slow its adoption. Our objective was to measure TRA rates of success and fluoroscopy time per vessel after 'radial-first' adoption and to compare these rates to those obtained with TFA. METHODS: We examined 500 consecutive cerebral angiograms on an intent-to-treat basis during the first full year of radial-first adoption, recording patient and procedural characteristics and outcomes. RESULTS: Over a 9-month period at a single center, 457 of 500 angiograms (91.4%) were performed with intent-to-treat via TRA, and 431 cases (86.2%) were ultimately performed via TRA. One patient (0.2%) experienced a temporary neurologic deficit in the TRA group, and none (0%) did in the TFA group (p=0.80). The mean±SD fluoroscopy time per vessel decreased significantly from the first half of the study to the second half for TRA (5.0±3.8 vs 3.4±3.5 min/vessel; p<0.001), while TFA time remained unchanged (3.7±1.8 vs 3.5±1.4 min/vessel; p=0.69). The median fluoroscopy time per vessel for TRA became faster than that for TFA after 150 angiograms. CONCLUSION: Of 500 consecutive angiograms performed during the first full year of radial-first implementation, 86.2% were performed successfully using TRA. TRA efficiency exceeded that of TFA after 150 angiograms. Concerns about the length of procedure or radiation exposure should not be barriers to TRA adoption.

Multi-modal endovascular management of traumatic pseudoaneurysm and arteriovenous fistula of the ascending cervical artery: A technical report and review of literature.

OBJECTIVE: The management of traumatic pseudoaneurysm (PA) with concomitant arteriovenous fistula (AVF) arising from the thyrocervical trunk is challenging and rarely reported. Here, the usefulness of a multi-modal endovascular strategy for management of traumatic PA and AVF arising from the thyrocervical trunk is presented. A literature review describing unique clinical features and management strategies of traumatic vascular lesions of the thyrocervical trunk is included. METHODS: A 58-year-old man presented with two PAs arising from the ascending cervical artery (AsCA) and a robust AVF between the AsCA and the left vertebral venous plexus which arose acutely after a stabbing incident. These lesions were managed with endovascular vessel sacrifice via coiling and controlled Onyx injection. Relevant literature was identified via a targeted search of the PubMed database. RESULTS: Post-management angiography demonstrated complete occlusion of the two traumatic PAs and successful disconnection of the concomitant AVF. Our literature review demonstrates a shift in preferred management approach from invasive surgery to endovascular treatment due to the lower risk and cosmetic preferability. CONCLUSION: Timely treatment of enlarging PA is necessary for reducing associated morbidity and mortality. While surgical resection has been the mainstay therapy, endovascular management has gained popularity in recent years. The choice of endovascular technique is variable and should be individualized based on patient's clinical status, associated risk factors, and lesion morphology. We have shown that parent vessel sacrifice is safe and effective. Reconstruction with a combination of stents, coils, glue, or liquid embolics may be necessary when collateral flow is limited.

A propensity-adjusted comparison of middle meningeal artery embolization versus conventional therapy for chronic subdural hematomas.

OBJECTIVE: Middle meningeal artery (MMA) embolization is a promising treatment strategy for chronic subdural hematomas (cSDHs). However, studies comparing MMA embolization and conventional therapy (surgical intervention and conservative management) are limited. The authors aimed to compare MMA embolization versus conventional therapy for cSDHs using a propensity-adjusted analysis. METHODS: A retrospective study of all patients with cSDH who presented to a large tertiary center over a 2-year period was performed. MMA embolization was compared with surgical intervention and conservative management. Neurological outcome was assessed using the modified Rankin Scale (mRS). A propensity-adjusted analysis compared MMA embolization versus surgery and conservative management for all individual cSDHs. Primary outcomes included change in hematoma diameter, treatment failure, and complete resolution at last follow-up. RESULTS: A total of 231 patients with cSDH met the inclusion criteria. Of these, 35 (15%) were treated using MMA embolization, and 196 (85%) were treated with conventional treatment. On the latest follow-up, there were no statistically significant differences between groups in the percentage of patients with worsening mRS scores. Of the 323 total cSDHs found in 231 patients, 41 (13%) were treated with MMA embolization, 159 (49%) were treated conservatively, and 123 (38%) were treated with surgical evacuation. After propensity adjustment, both surgery (OR 12, 95% CI 1.5-90; p = 0.02) and conservative therapy (OR 13, 95% CI 1.7-99; p = 0.01) were predictors of treatment failure and incomplete resolution on follow-up imaging (OR 6.1, 95% CI 2.8-13; p < 0.001 and OR 5.4, 95% CI 2.5-12; p < 0.001, respectively) when compared with MMA embolization. Additionally, MMA embolization was associated with a significant decrease in cSDH diameter on follow-up relative to conservative management (mean -8.3 mm, 95% CI -10.4 to -6.3 mm, p < 0.001). CONCLUSIONS: This propensity-adjusted analysis suggests that MMA embolization for cSDH is associated with a greater extent of hematoma volume reduction with fewer treatment failures than conventional therapy.

Middle meningeal artery embolization for chronic subdural hematoma: an institutional technical analysis.

BACKGROUND: Recently, middle meningeal artery (MMA) embolization has emerged as a potentially safe and effective method of treating chronic subdural hematoma (cSDH). OBJECTIVE: To report a single-center experience with MMA embolization and examines the type of embolic material used, the extent of penetration, and the number of MMA branches embolized. METHODS: A retrospective analysis of all patients with MMA embolization from 2018 through 2019 was performed. A failed outcome was defined as either surgical rescue and/or greater than 10 mm of hematoma residual or reaccumulation following embolization. RESULTS: Of 35 patients, surgery had failed for 9 (26%) and initial conservative treatment had failed for 6 (17%). Of 41 MMA embolizations, including those in six patients with bilateral cSDH who underwent bilateral MMA embolization, 29 (72%) were performed using ethylene vinyl alcohol copolymer (Onyx), 7 (17%) using particles, and 5 (12%) using n-butyl cyanoacrylate. Both the anterior and posterior MMA divisions were embolized in 29 cases (71%); distal penetration of these branches was achieved in 25 embolizations (61%). Twenty-six (63%) cSDHs completely resolved. Complete resolution was seen in 22 of 29 hematomas (76%) in which both anterior and posterior MMA branches were occluded versus 4 of 12 (33%) following single-branch embolization (p=0.014). Embolization of one cSDH (2%) failed. CONCLUSION: MMA embolization of cSDHs appears to be both safe and efficacious. Furthermore, embolization of both the anterior and posterior MMA branches may be associated with increased odds of complete resolution.

Comparison of aspiration-first versus stentriever-first techniques in performing mechanical thrombectomy for large vessel occlusions.

BACKGROUND: Both stentriever and direct-aspiration thrombectomy effectively treat large-vessel occlusions. However, data are limited comparing clinical outcomes after aspiration-first versus stentriever-assisted aspiration for thrombectomy. METHODS: A retrospective cohort study compared procedure times and radiographic outcomes after two mechanical thrombectomy techniques (aspiration first or stentriever). To minimize bias and variability inherent to multi-operator series, we assessed consecutive patients with cerebrovascular occlusions treated by a single surgeon during a 1 year period at two stroke centers. Expanded Thrombolysis in Cerebral Infarction (eTICI) grades were assessed by an investigator blinded to treatment. RESULTS: Data from 93 patients (median age 70 years) were analyzed: 73 patients (78.5%) were treated with a strentriever-first strategy and 20 (21.5%) were treated with aspiration first, with stentriever rescue therapy required in only three of these cases following unsuccessful aspiration. There were no significant differences in patient demographics, sites of occlusion, or rates of tandem occlusions between aspiration-first and stentriever-assisted groups (p≥0.36). The rate of first-pass eTICI ≥2b was 75.0% (15/20) for aspiration-first and 52.1% (38/73) for strentriever-first groups (p=0.07), while the rate of final eTICI ≥2b was 100% (20/20) and 82.2% (60/72), respectively (p=0.04). The aspiration-first technique was associated with procedural times ≤25 min in a multivariable analysis (adjusted OR 4.77, 95% CI 1.15 to 18.39; p=0.03). CONCLUSIONS: In this single-surgeon series, an aspiration-first technique was associated with a statistically significant improvement in eTICI outcomes and faster procedure times compared with stentriever-assisted aspiration. Further prospective studies are necessary to minimize selection bias inherent in this study design.

Retractorless interforniceal approach for microsurgical resection of a papillary tumor of the pineal region: operative video and technical nuances.

In this illustrative video, the authors demonstrate microsurgical resection of a papillary tumor of the pineal region using a retractorless interforniceal approach via the anterior interhemispheric transcallosal route. The tumor presented to the posterior third ventricle occluding the cerebral aqueduct, resulting in obstructive hydrocephalus. The retractorless interforniceal approach is performed in the lateral position with BICOL collagen spacers to keep the corridor open. Gross-total resection was achieved, and the patient was neurologically intact without needing a permanent shunt. The operative nuances and pearls of technique for safe microdissection and gentle handling of the retractorless interforniceal approach are demonstrated. The video can be found here: https://stream.cadmore.media/r10.3171/2021.4.FOCVID2139.

Posterior resection of sacral osteosarcoma utilizing cement-infused chest tube interbody reconstruction and lumbopelvic fusion.

BACKGROUND: Primary osteosarcoma (OS) of the spine is very rare. En bloc resection of spinal OS is challenging due to anatomical constraints. Surgical planning must balance the benefits of en bloc resection with its potential risks of causing a significant neurological deficit. In this case, we successfully performed a posterior-only approach for decompression with S1 reconstruction via a cement-infused chest tube interbody device, along with a navigated L4 to pelvis fusion. CASE DESCRIPTION: A 49-year-old female presented with a primary sacral OS. Computed tomography (CT) and magnetic resonance (MR) imaging revealed an S1 lytic vertebral body lesion with severe stenosis and progressive L5 on S1 anterior subluxation. Surgical decompression with tumor resection and S1 corpectomy with S1 reconstruction via a cement-infused 32-French chest tube interbody device accompanied by L4 -pelvis fusion utilizing S2-alar-iliac screws was completed. 6 months postoperatively, the patient continues to have significant pain relief and the instrumentation remains intact. CONCLUSION: A 49-year-old female with an S1 OS successfully underwent a posterior-only approach that included an S1 corpectomy with anterior column reconstruction via a cement-infused chest tube interbody plus a navigated L4 to pelvis fusion.

Reaccessing an occluded radial artery for neuroendovascular procedures: techniques and complication avoidance.

BACKGROUND: Radial artery occlusion (RAO) occurs in 1% to 10% of cases following transradial arterial access (TRA) for neuroendovascular procedures. When repeat access is required in patients discovered to have RAO, a transfemoral approach is often used. This study reports experience with repeat TRA procedures at a single center and techniques for reaccessing an occluded radial artery in select patients. METHODS: The electronic records of all patients who underwent multiple neuroendovascular procedures with an attempted TRA as the index procedure at a single center from July 2019 through February 2020 were reviewed. RESULTS: There were 656 TRA attempts for diagnostic angiography or intervention from July 2019 through February 2020. A total of 106 patients underwent a repeated attempt at TRA. Techniques for reaccessing an occluded radial artery were implemented halfway through the study period. One hundred patients (94.3%) had a successful second radial catheterization. Six patients required conversion to a transfemoral approach: five for RAO and one for radial branch perforation during the index procedure. After we implemented our techniques for reaccess, four additional patients with RAO successfully underwent TRA. There were no short-term complications, including pain, vessel perforation, forearm hematoma, or hand ischemia, following successful repeat catheterization of a previously occluded radial artery. CONCLUSION: RAO is not an absolute limitation for attempting TRA in patients undergoing repeat catheterization. Reaccessing the radial artery after occlusion is feasible for repeat neuroendovascular procedures.

Propensity-adjusted cost analysis of radial versus femoral access for neuroendovascular procedures.

BACKGROUND: Transradial artery (TRA) access for neuroendovascular procedures is associated with fewer complications than transfemoral artery (TFA) access. This study compares hospital costs associated with TRA access to those associated with TFA access for neurointerventions. METHODS: Elective neuroendovascular procedures at a single center were retrospectively analyzed from October 1, 2018 to May 31, 2019. Hospital costs for each procedure were obtained from the hospital financial department. The primary outcome was the difference in the mean hospital costs after propensity adjustment between patients who underwent TRA compared with TFA access. RESULTS: Of the 338 elective procedures included, 63 (19%) were performed through TRA versus 275 (81%) through TFA access. Diagnostic procedures were more common in the TRA cohort (51 of 63, 81%) compared with the TFA cohort (197 of 275, 72%), but the difference was not significant (p=0.48). The TRA cohort had a shorter length of hospital stay (mean (SD) 0.3 (0.5) days) compared with the TFA cohort (mean 0.7 (1.3) days; p=0.02) and lower hospital costs (mean $12 968 ($6518) compared with the TFA cohort (mean $17 150 ($10 946); p=0.004). After propensity adjustment for age, sex, symptoms, angiographic findings, procedure type, sheath size, and catheter size, TRA access was associated with a mean hospital cost of $2514 less than that for TFA access (95% CI -$4931 to -$97; p=0.04). CONCLUSION: Neuroendovascular procedures performed through TRA access are associated with lower hospital costs than TFA procedures. The lower cost is likely due to a decreased length of hospital stay for TRA.

Left distal radial access in patients with arteria lusoria: insights for cerebral angiography and interventions.

BACKGROUND: The transradial approach (TRA) is frequently used for neurointerventional procedures as it is safer, improves patient comfort, and decreases costs and procedural time in comparison with the transfemoral approach (TFA). Patients with arteria lusoria, or an aberrant right subclavian artery (ARSA), provide a unique challenge for cerebral angiography and interventions when using the TRA. OBJECTIVE: To examine the hypothesis that the extreme angulation encountered while accessing the great vessels from the right TRA could be overcome by reversing the approach to the left distal TRA (dTRA). METHODS: A prospectively maintained database of transradial neurointerventional cases since 2018 was searched. Six cases from 850 were identified, in which the left dTRA was used. Three cases were for patients with an ARSA. For the three cases of interest, patient history, pathology, imaging, and access techniques were reviewed. RESULTS: Two diagnostic cerebral angiography cases and one intervention were successfully performed through a left dTRA. CONCLUSIONS: Proper positioning of the left wrist and familiarity with forming the Simmons catheter can overcome this anatomical challenge. This technique and results further demonstrate that the left distal radial artery is a feasible access site for catheterization of bilateral carotid, left vertebral, and right subclavian arteries for patients with an ARSA.

Chondromyxoid Fibroma of the Sacral Spine.

Background and Importance. Chondromyxoid fibromas are rare tumors of cartilaginous origin typically found in long bones. They usually present during the second and third decades of life. In this case report, we describe the case of a 60-year-old male who presented with back pain and was later found to have a sacral mass. Further immunohistochemical analysis determined that the mass was a chondromyxoid fibroma. Clinical Presentation. A 60-year-old male presented with worsening lower back pain over the course of 2 years. Magnetic resonance imaging demonstrated a destructive mass centered at S4 with heterogeneous enhancement. The patient underwent an S3-to-Co1 laminectomy for gross total resection of the tumor. Histology demonstrated a biphasic, lobulated appearance, characteristic of a chondromyxoid fibroma. The tissue stained faintly positive for multicytokeratin, and it was negative for markers S-100 protein and brachyury, indicating that it was not a chordoma. Conclusion. Only 8 cases have documented sacral chondromyxoid fibroma. As these are exceedingly rare tumors, especially within the sacral spine, the differential diagnosis includes other malignant tumors more likely to be found in the spine, particularly chordomas and chondrosarcomas. Immunohistochemistry and histology are essential in making a definitive diagnosis. This case provides a comprehensive illustration of the clinical presentation, radiographic findings, and immunohistochemistry of sacral chondromyxoid fibroma.

Epidermoid Cyst of the Lumbar Spine After Lumbar Puncture: A Clinical, Radiographic, and Pathologic Correlation.

BACKGROUND: Epidermoid cysts can rarely arise as a late complication of lumbar puncture. We describe a young man who had a remote history of a lumbar puncture and who was subsequently found to have a lumbar spinal epidermoid cyst on imaging, after presenting with lower extremity radicular pain. CASE DESCRIPTION: A 24-year-old man with a remote history of lumbar puncture presented with lower back pain and radicular leg pain which had been ongoing for over a year. Despite conservative management, the patient's symptoms progressed to worsening back pain and left L4 radiculopathy. Magnetic resonance imaging of the lumbar spine demonstrated a peripherally enhancing, intradural, extramedullary lesion at L4-5. Diffusion-weighted imaging revealed diffusion restriction within the lesion, characteristic of an epidermoid cyst. The patient underwent an L4-5 laminectomy for resection of the intradural tumor. The lesion was noted to contain pearly white granules consistent with the appearance of an epidermoid cyst. Histopathology confirmed the diagnosis. On follow-up examination, the patient demonstrated improvement of his back pain and resolution of radicular symptoms. CONCLUSIONS: Lumbar spinal epidermoid cysts may be either congenital or secondary to an iatrogenic cause. This patient had a remote history of lumbar puncture during workup for meningitis as a child. As a complication of a lumbar puncture, the formation of an epidermoid cyst can occur and is thought to be the result of implanted cutaneous tissue. This case provides a comprehensive illustration of the clinical, radiographic, intraoperative, and pathologic findings consistent with an iatrogenic epidermoid cyst.

Feasibility and Challenges of Microsurgical Resection of Colloid Cysts in Patients with Preexisting Ventriculoperitoneal Shunts.

BACKGROUND: Colloid cysts are the most common third ventricular tumor and may present with symptoms related to obstructive hydrocephalus. Although definitive endoscopic or microsurgical resection is the standard of care, patients may receive temporizing ventriculoperitoneal shunts when definitive management is deferred. Subsequent definitive treatment can be challenging because of the ventricular collapse and narrowing of the operative corridor. There is currently no literature evaluating the feasibility of definitive colloid cyst resection in patients with preexisting ventriculoperitoneal shunts. METHODS: We retrospectively reviewed records for patients undergoing colloid cyst resection between 2009 and 2019 to identify patients with preexisting shunts prior to surgery. RESULTS: Three patients had preexisting ventriculoperitoneal shunts. Two patients had been shunted at outside institutions where microsurgical or endoscopic resection was not available. One patient received a shunt from an outside surgeon when she was deemed a poor surgical candidate because of cardiac instability. All 3 patients underwent successful gross total colloid cyst resection via the transcallosal approach without recurrences during a mean follow-up of 4.2 years. All patients had intact cognitive and memory function and returned to work. CONCLUSIONS: Surgical resection of colloid cysts is possible despite a preexisting ventriculoperitoneal shunt. Because the ventricular space may be collapsed postoperatively because of cerebrospinal fluid diversion, a transcortical route (either endoscopic or microscopic) can be complicated by a small operative corridor with reduced visibility. The transcallosal approach was safe and feasible in these cases for providing midline access with adequate visualization for complete resection despite ventricular collapse.

Complications of femoral versus radial access in neuroendovascular procedures with propensity adjustment.

BACKGROUND: The transradial artery (TRA) approach for neuroendovascular procedures continues to gain popularity, but neurointerventionalists still lag behind interventional cardiologists in the adoption of a TRA-first approach. This study compares the complications and efficiency of the TRA approach to the standard transfemoral artery (TFA) approach at our institution during our initial phase of adopting a TRA-first approach. METHODS: A retrospective analysis was performed on all consecutive neuroangiographic procedures performed at a large cerebrovascular center from October 1, 2018 to June 30, 2019. The standard TFA approach was compared with TRA access, with the primary outcome of complications analyzed via a propensity-adjusted analysis. RESULTS: A total of 1050 consecutive procedures were performed on 877 patients during this 9-month period; 206 (20%) procedures were performed via TRA and 844 (80%) via TFA. The overall complication rate was significantly higher with the TFA procedures than with the TRA procedures (7% (60/844) vs 2% (4/206), respectively; p=0.003). A propensity-adjusted analysis showed that the TFA approach was a significant risk factor for a complication (OR 3.6, 95% CI 1.3 to 10.2, p=0.01). However, the propensity analysis showed that fluoroscopy times were on average 4 min less for TFA procedures than for TRA procedures (p=0.003). CONCLUSION: The TRA approach for neuroendovascular procedures appears to be safer than the TFA approach. Although a steep learning curve is initially encountered when adopting the TRA approach, the transition to a TRA-first practice can be performed safely for neurointerventional procedures and may reduce complications.