Neurological Surgery Residency Programs in the United States: A National Cross-Sectional Survey.

BACKGROUND AND OBJECTIVES: The Accreditation Council for Graduate Medical Education has approved 117 neurological surgery residency programs which develop and educate neurosurgical trainees. We present the current landscape of neurosurgical training in the United States by examining multiple aspects of neurological surgery residencies in the 2022-2023 academic year and investigate the impact of program structure on resident academic productivity. METHODS: Demographic data were collected from publicly available websites and reports from the National Resident Match Program. A 34-question survey was circulated by e-mail to program directors to assess multiple features of neurological surgery residency programs, including curricular structure, fellowship availability, recent program changes, graduation requirements, and resources supporting career development. Mean resident productivity by program was collected from the literature. RESULTS: Across all 117 programs, there was a median of 2.0 (range 1.0-4.0) resident positions per year and 1.0 (range 0.0-2.0) research/elective years. Programs offered a median of 1.0 (range 0.0-7.0) Committee on Advanced Subspecialty Training-accredited fellowships, with endovascular fellowships being most frequently offered (53.8%). The survey response rate was 75/117 (64.1%). Of survey respondents, the median number of clinical sites was 3.0 (range 1.0-6.0). Almost half of programs surveyed (46.7%) reported funding mechanisms for residents, including R25, T32, and other in-house grants. Residents received a median academic stipend of $1000 (range $0-$10 000) per year. Nearly all programs (93.3%) supported wellness activities for residents, which most frequently occurred quarterly (46.7%). Annual academic stipend size was the only significant predictor of resident academic productivity (R 2 = 0.17, P = .002). CONCLUSION: Neurological surgery residency programs successfully train the next generation of neurosurgeons focusing on education, clinical training, case numbers, and milestones. These programs offer trainees the chance to tailor their career trajectories within residency, creating a rewarding and personalized experience that aligns with their career aspirations.

Clinical outcomes of stereotactic biopsy on children with pontine diffuse midline glioma.

INTRODUCTION: Diffuse midline glioma (DMG) of the pons occurs in pediatric patients and carries a dismal prognosis. Biopsy is not necessary for diagnosis but provides information, particularly H3K27M status, with prognostic implications. Additionally, biopsy information may open therapeutic options such as clinical trials that require mutation status. Therefore, we sought to assess the safety of surgical biopsy in DMG patients as well as its potential impact on clinical course. METHODS: Retrospective analysis of patients who were radiographically and clinically diagnosed with pontine DMG in the last 5 years was performed. We assessed demographic, clinical, radiographic, surgical, and follow-up data. RESULTS: 25 patients were included; 18 (72%) underwent biopsy while 7 (28%) declined. 12 biopsies (67%) were performed with robotic arm and 5 (27%) with frameless stereotaxy. Three biopsied patients (17%) experienced new post-operative neurologic deficits (1 facial palsy, 1 VI nerve palsy and 1 ataxia) that all resolved at 2-week follow-up. All biopsies yielded diagnostic tissue. Fourteen patients (78%) had H3K27M mutation. Median OS for H3K27M patients was 10 months compared to 11 months in the wild-type patients (p = 0.30, log-rank test). Median OS for patients enrolled in clinical trials was 12 months compared to 8 months for non-trial patients (p = 0.076). CONCLUSION: In our series, stereotactic pontine DMG biopsies did not carry any permanent deficit or complication and yielded diagnostic tissue in all patients. Similar post-operative course was observed in both robot-assisted and frameless stereotactic approaches. There was no significant difference in survival based on mutation status or clinical trial enrollment.

Removal of a flanged ventricular catheter: illustrative case.

BACKGROUND: Flanged ventricular catheters were created in the 1970s to decrease shunt failure by preventing the holes at the catheter tip from contacting the choroid plexus. However, the flanges on the catheter frequently scarred within and tether to the choroid plexus, resulting in higher rates of intraventricular hemorrhage when removed. Today, flanged catheters are rarely encountered. OBSERVATIONS: The authors describe an illustrative case of a 7-year-old girl recently adopted from another country with a history of myelomeningocele and shunted hydrocephalus. She had been treated with a flanged catheter at birth. She presented with a shunt infection, which required removal of the flanged catheter tethered to the choroid. LESSONS: The authors illustrate the safe removal of a posterior-entry flanged ventricular catheter tethered to the choroid plexus using monopolar flexible electrocautery. The removal was monitored with a flexible endoscope inserted from an ipsilateral anterior burr hole and was followed by an endoscopic third ventriculostomy.

Transvenous Embolization of Dural Arteriovenous Fistulas Through the Galenic (Deep Venous) System: Multicenter Case Series and Meta-Analysis.

BACKGROUND AND OBJECTIVES: Arteriovenous fistulas involving the deep venous system have often been treated with microsurgery or transarterial embolization. Increasing familiarity with transvenous navigation and improved endovascular access systems may facilitate transvenous embolization (TVE) for these rare and challenging lesions. METHODS: We performed a retrospective study of neurointerventional databases of 6 high-volume centers. We identified all cases of arteriovenous fistulas with deep transvenous embolizations for arteriovenous fistula. Details regarding demographics, fistula characteristics, treatment considerations, clinical outcomes, and fistula occlusion were obtained and analyzed. The meta-analysis used the same inclusion criteria. RESULTS: Seventeen cases of TVE were identified. The most common reasons for TVE included prior treatment failure with microsurgery (n = 2) or transarterial embolization (n = 3) or inaccessible arterial pedicles (n = 4). For patients with full clinical outcome data (n = 14), 2 patients had worsened modified Rankin Scale, 8 patients had no change, and 4 were improved at a median clinical follow-up of 3.5 months. Angiographic obliteration was achieved in 15/17 cases (88.2%). In 1 case, catheterization around a sharp turn in the basal vein of Rosenthal could not be performed. In another case, despite successful TVE, there was residual lesion which was treated 1 year later by microsurgical clipping and excision. CONCLUSION: Transvenous approaches for embolization of deep arteriovenous fistulas have become possible with modern endovascular catheter systems and liquid embolics. These lesions can be treated safely and effectively through endovascular approaches, which may spare patients the traversal of deep structures needed for microsurgical approaches to these regions. The outcomes of TVE are comparable with published outcomes of microsurgical interruption.

Epilepsy Surgery in Young Children With Tuberous Sclerosis Complex: A Novel Hybrid Multimodal Surgical Approach.

BACKGROUND: Surgery has become integral in treating children with tuberous sclerosis complex (TSC)-related drug-resistant epilepsy (DRE). OBJECTIVE: To describe outcomes of a multimodal diagnostic and therapeutic approach comprising invasive intracranial monitoring and surgical treatment and compare the complementary techniques of open resection and magnetic resonance-guided laser interstitial thermal therapy. METHODS: Clinical and radiographic data were prospectively collected for pediatric patients undergoing surgical evaluation for TSC-related DRE at our tertiary academic hospital. Seizure freedom, developmental improvement, and Engel class were compared. RESULTS: Thirty-eight patients (20 females) underwent treatment in January 2016 to April 2019. Thirty-five underwent phase II invasive monitoring with intracranial electrodes: 24 stereoencephalography, 9 craniotomy for grid/electrode placement, and 2 grids + stereoencephalography. With the multimodal approach, 33/38 patients (87%) achieved >50% seizure freedom of the targeted seizure type after initial treatment; 6/9 requiring secondary treatment and 2/2 requiring a third treatment achieved >50% freedom. The median Engel class was II at last follow-up (1.65 years), and 55% of patients were Engel class I/II. The mean age was lower for children undergoing open resection (2.4 vs 4.9 years, P = .04). Rates of >50% reduction in seizures (86% open resection vs 88% laser interstitial thermal therapy) and developmental improvement (86% open resection vs 83% magnetic resonance-guided laser interstitial thermal therapy) were similar. CONCLUSION: This hybrid approach of using both open surgical and minimally invasive techniques is safe and effective in treating DRE secondary to TSC. Clinical trials focused on treatment method with longer follow-up are needed to determine the optimal candidates for each approach and compare the treatment modalities more effectively.

Management strategies of unanticipated intracranial stenosis during mechanical thrombectomy for acute stroke: A survey of academic neurointerventionalists.

BACKGROUND: The optimal approach to the management of intracranial atherosclerotic disease (ICAD) at the time of mechanical thrombectomy (MT) for large vessel occlusion (LVO) remains controversial. The goal of this study is to characterize current practices concerning this challenging clinical situation in a survey of practicing neurointerventionalists. METHODS: An electronic questionnaire was sent to a cross-section of North American academic neurointerventionalists using publicly available contact information and departmental websites. Prior to analysis, responses were anonymized and categorized by region. RESULTS: A total of 136/360 responses were recorded from the U.S. and Canada. The mean number of years of practicing as a neurointerventionalist among the respondents was 10.5 (± 6.2 years). ICAD was perceived as a causative factor during MT for LVO in 5-10% of thrombectomy cases. The most common first-line treatment approach for significant ICAD, assuming a TICI 2b or better reperfusion, was medical therapy (77.9% of respondents), followed by angioplasty + stent placement (8.8% of respondents). There were no significant differences in the first line treatment of ICAD in LVO between geographical regions (p = 0.815). CONCLUSION: The approach to underlying ICAD in LVO varies widely; however, the majority of neurointerventionalists prefer medical therapy with DAPT as a first-line treatment approach. The current survey highlights the need for studies that better define the optimal timing and modality of treatment, along with an evidence-based framework for balancing the risks associated with these treatment approaches.

The impact of a night float system on operative experience in neurosurgery residency.

OBJECTIVE: Since the Accreditation Council for Graduate Medical Education (ACGME) implemented duty-hour restrictions in 2003, many residency programs have adopted a night float system to comply with time constraints. However, some surgical subspecialities have been concerned that use of a night float system deprives residents of operative experience. In this study, the authors describe their training program's transition to a night float system and its impact on resident operative experience. METHODS: The authors conducted a single-program study of resident surgical case volume before and after implementing the night float system at 3 of their 5 hospitals from 2014 to 2020. The authors obtained surgical case numbers from the ACGME case log database. RESULTS: Junior residents received a concentrated educational experience, whereas senior residents saw a significant decrease from 112 calls/year to 17. Logged cases significantly increased after implementation of the night float system (8846 vs 10,547, p = 0.04), whereas cases at non-night float hospitals remained the same. This increase was concurrent with an increase in hospital cases. This difference was mainly driven by senior resident cases (p = 0.010), as junior and chief residents did not show significant differences in logged cases (p > 0.40). Lead resident cases increased significantly after implementation of the night float system (6852 vs 8860, p = 0.04). When normalized for increased hospital cases, resident case increases were not statistically significant. CONCLUSIONS: Transitioning to a night float call system at the authors' institution increased overall resident operative cases, particularly for lead resident surgeons. Based on the results of this study, the authors recommend the use of a night float call system to consolidate night calls, which increases junior resident-level educational opportunities and senior resident cases.

A steroid receptor coactivator small molecule "stimulator" attenuates post-stroke ischemic brain injury.

Introduction: Pathologic remodeling of the brain following ischemic stroke results in neuronal loss, increased inflammation, oxidative stress, astrogliosis, and a progressive decrease in brain function. We recently demonstrated that stimulation of steroid receptor coactivator 3 with the small-molecule stimulator MCB-613 improves cardiac function in a mouse model of myocardial ischemia. Since steroid receptor coactivators are ubiquitously expressed in the brain, we reasoned that an MCB-613 derivative (MCB-10-1), could protect the brain following ischemic injury. To test this, we administered MCB-10-1 to rats following middle cerebral artery occlusion and reperfusion. Methods: Neurologic impairment and tissue damage responses were evaluated on day 1 and day 4 following injury in rats treated with control or 10-1. Results: We show that 10-1 attenuates injury post-stroke. 10-1 decreases infarct size and mitigates neurologic impairment. When given within 30 min post middle cerebral artery occlusion and reperfusion, 10-1 induces lasting protection from tissue damage in the ischemic penumbra concomitant with: (1) promotion of reparative microglia; (2) an increase in astrocyte NRF2 and GLT-1 expression; (3) early microglia activation; and (4) attenuation of astrogliosis. Discussion: Steroid receptor coactivator stimulation with MCB-10-1 is a potential therapeutic strategy for reducing inflammation and oxidative damage that cause neurologic impairment following an acute ischemic stroke.

Flow diversion of a dissecting PICA aneurysm.

A 47-year-old female with a history of a ruptured left posterior inferior cerebellar artery (PICA) aneurysm, status post coil embolization and retreatment for recurrence, presented with evidence of a recurrent dissecting PICA aneurysm. Given that these aneurysms are considered high risk and have a greater propensity for rupture than anterior circulation aneurysms, retreatment was recommended. With the patient's strong preference for endovascular therapy, flow diversion with a Silk Vista Baby was performed. Given the low-profile design of the device, a radial artery approach and coaxial technique were used to deploy the flow diverter. The device was successfully placed, with complete obliteration of the aneurysm after 1 year. The video can be found here: https://stream.cadmore.media/r10.3171/2022.7.FOCVID2247.

PulseRider-assisted embolization of a distal anterior cerebral artery bifurcation aneurysm: illustrative case.

BACKGROUND: PulseRider is an endovascular device that can be a useful adjunctive device for wide-necked bifurcation aneurysms. However, its use in distal vessels such as the anterior cerebral artery (ACA) has not been widely reported. OBSERVATIONS: The authors reported the case of a 75-year-old woman who underwent coiling of a 6.9-mm distal ACA aneurysm with PulseRider assistance. Using a partially intraaneurysmal deployment technique, the wide-necked aneurysm was successfully embolized, resulting in Raymond-Roy class II occlusion without intra- or periprocedural complications. LESSONS: This case illustrates a novel approach to treatment for wide-necked distal ACA aneurysms, which can be challenging to treat via traditional endovascular means. PulseRider can be safely used to treat distal ACA aneurysms with minimal residual aneurysm.

3-Dimensional Modeling in Virtual Reality for Resection of a Pineal Region Falcotentorial Meningioma.

We present a parietal interhemispheric approach to resect a pineal region falcotentorial meningioma. Three-dimensional (3D) modeling was used to visualize and plan the surgical approach in virtual reality (Video 1). A 78-year-old woman was incidentally found to have a slow-growing falcotentorial meningioma. The tumor was first treated with stereotactic radiosurgery, but the patient had progressive confusion, memory issues, and bilateral temporal field cuts with interval expansion of the tumor and significantly increased peritumoral vasogenic edema on magnetic resonance imaging. After recommending tumor resection, the patient consented to surgery and underwent resection via a posterior interhemispheric subsplenial approach. Using a 3D model in virtual reality, we discuss the advantages and disadvantages of various classical approaches to the pineal region for resection of this tumor.1-3 Falcotentorial meningiomas often displace the deep veins inferiorly, making an interhemispheric approach more favorable.4-6 Preoperative visualization of critical deep venous structures with the 3D model was a valuable adjunct to magnetic resonance imaging for achieving safe resection. We depict key steps of the surgical planning process using virtual reality and demonstrate how simulation can be used to evaluate risks and benefits of different surgical corridors. A small rim of residual tumor adherent to the deep cerebral veins was intentionally left behind in order to minimize risk of morbidity to the patient.7 At 1-month follow-up, the patient's cognition had returned to baseline and her vision had significantly improved. Ultimately, surgical planning using virtual reality promotes both neurosurgical education and patient safety through clear visualization and understanding of different surgical approaches.

Trapping and P2-P3 Posterior Inferior Cerebellar Artery Reanastomosis for Treatment of a Ruptured Fusiform Aneurysm: Application of Fourth-Generation Technique: 2-Dimensional Operative Video.

Aneurysms of the posterior inferior cerebellar artery (PICA) represent the second most common posterior circulation aneurysm and commonly have complex morphology. Various bypass options exist for PICA aneurysms,1-6 depending on their location relative to brainstem perforators and the vertebral artery, and the presence of nearby donor arteries. We present a case of a man in his late 40s who presented with 3 d of severe headache. He was found to have a fusiform right P2-segment PICA aneurysm. Preoperative angiogram demonstrated the aneurysm and a redundant P3 caudal loop that came in close proximity to the healthy P2 segment proximal to the aneurysm. The risks and benefits of the procedure were discussed with the patient, and they consented for a right far lateral approach craniotomy with partial condylectomy for trapping of the aneurysm with bypass. The aneurysm was trapped proximally and distally. The P3 was transected just distal to the aneurysm and brought toward the proximal P2 segment, facilitated by a lack of perforators on this redundant distal artery. An end-to-side anastomosis was performed. Postoperative angiogram demonstrated exclusion of the aneurysm and patent bypass. The patient recovered well and remained without any neurological deficit at 6-mo follow-up. This case demonstrates the use of a "fourth-generation"5,7,8 bypass technique. These techniques represent the next innovation beyond third-generation intracranial-intracranial bypass. In this type 4B reanastomosis bypass, an unconventional orientation of the arteries was used. Whereas reanastomosis is typically performed end-to-end, the natural course of these arteries and the relatively less-mobile proximal P2 segment made end-to-side the preferred option in this case. Fourth-generation bypass techniques open up more configurations for reanastomosis, using the local anatomy to the surgeon's advantage. The patient consented to the described procedure and consented to the publication of their image.

Microsurgical Resection of Giant Thoraco-Lumbo-Sacral Ependymoma With Hybrid Spinal Reconstruction Using Multilevel Laminoplasty and Up-Front Thoracolumbar Posterior Fixation: 2-Dimensional Operative Video.

Extensive multifocal intradural lesions in children present a formidable challenge. This surgical video illustrates our management of a 14-yr=old boy with two intradural mass lesions on magnetic resonance imaging (MRI): one at T2-5 and the other from T12 through the sacral cul-de-sac. In a single procedure, we performed a T2-5 laminectomy and laminoplasty and T12-sacrum laminectomy for tumor resection. For reconstruction, we performed complete laminoplasty at all levels with supplementation at the thoracolumbar junction via T11-L2 posterior spinal fixation and allograft placement for fusion. In this video, we illustrate the microsurgical challenges of intradural tumor resection in both the thoracic cord and amidst the cauda equina. In young patients, prevention of postsurgical spinal deformity is of paramount concern. We discuss considerations for long-segment spinal stabilization in an adolescent and describe our decision-making to perform stabilization at the thoracolumbar junction to supplement laminoplasty while preserving function. The patient and their family consented to the procedure. Image of the article at 0:51 is from McGirt et al, Short-term progressive spinal deformity following laminoplasty versus laminectomy for resection of intradural spinal tumors: analysis of 239 patients, Neurosurgery, 2010, 66(5), 1005-1012, by permission of the Congress of Neurological Surgeons.

Comparison of Simultaneous Bilateral Internal Carotid Artery (ICA) 3-Dimensional Rotational Venography (3D-RV) versus Separate Bilateral ICA 3D-RV and Postprocessing 3D-3D Fusion.

BACKGROUND: Preoperative venogram of the superior sagittal sinus (SSS) is helpful to plan the surgical resection strategy in patients with parasagittal meningiomas invading the SSS. METHODS: Catheter 3-dimensional rotational venography (3D-RV) allows for SSS patency assessment and detection of alternative venous cortical drainage routes in patients with contraindication for magnet resonance venography. It is unknown if separate bilateral internal carotid artery 3D-RV followed by postprocessing 3D-3D fusion (technique 1) achieves the same imaging results as simultaneous bilateral internal carotid artery 3D-RV without postprocessing fusion (technique 2) needed. RESULTS: In this report we were able to confirm in 2 patients that both techniques achieve comparable imaging quality with similar amount of contrast use. CONCLUSIONS: Although technique 2 requires less radiation, technique 1 is favored due to the need for only 1 vessel access site and catheter with reduced risk for access site and ischemic complications.

Management of Cervical Kyphotic Deformity Associated With Loeys-Dietz Vasculopathy and Cardiac Transplantation: Case Report, Literature Review, and Strategies for Complex Skeletal Dysplasias.

Seventy-six percent of pediatric patients with Loeys-Dietz syndrome (LDS), a connective tissue disorder driven by a transforming growth factor-beta (TGF-B) pathway mutation, manifest cervical spine malformations. A prior series showed that 16% required surgical stabilization. Spine surgery in LDS is associated with an 88% complication rate due to poor bone quality and cerebrovascular ectasia. Of 77 patients with LDS, one patient who required spine surgery was identified in an institutional database from 2010 to 2020. A 15-year-old with LDS presented with symptomatic cervical myelopathy from a rapidly progressive and unstable cervical deformity. We performed a C5-6 corpectomy and an O-T2 posterior spinal fusion with recombinant human bone morphogenetic protein-2 (rhBMP-2). We achieved correction of her kyphosis and normalization of her neurologic status. She is neurologically well one year postoperatively with bony fusion. The management of a pediatric patient with LDS, orthotopic heart transplantation (OHT), and craniocervical deformity with instability is a novel challenge. Long-segment constructs are beneficial, rather than sparing the occiput or cervicothoracic junction. Off-label BMP may aid an LDS patient with TGF-B mutation and sternotomy. Surgeons should continue immunomodulatory and antiplatelet medications when required for OHT.

Virtual education in neurosurgery during the COVID-19 pandemic.

OBJECTIVE: Neurosurgical education in the US has changed significantly as a consequence of the novel coronavirus (COVID-19) pandemic. Institutional social distancing requirements have resulted in many neurosurgical programs utilizing video conferencing for educational activities. However, it is unclear how or if these practices should continue after the pandemic. The objective of this study was to characterize virtual education in neurosurgery and understand how it should be utilized after COVID-19. METHODS: A 24-question, 3-part online survey was administered anonymously to all 117 US neurosurgical residency programs from May 15, 2020, to June 15, 2020. Questions pertained to the current use of virtual conferencing, preferences over traditional conferences, and future inclinations. The Likert scale (1 = strongly disagree, 3 = neutral, 5 = strongly agree) was used. Comparisons were calculated using the Mann-Whitney U-test. Statistical significance was set at 0.05. RESULTS: One-hundred eight responses were recorded. Overall, 38 respondents (35.2%) were attendings and 70 (64.8%) were trainees. Forty-one respondents (38.0%) indicated attending 5-6 conferences per week and 70 (64.8%) attend national virtual conferences. When considering different conference types, there was no overall preference (scores < 3) for virtual conferences over traditional conferences. In regard to future use, respondents strongly agreed that they would continue the practice at some capacity after the pandemic (median score 5). Overall, respondents agreed that virtual conferences would partially replace traditional conferences (median score 4), whereas they strongly disagreed with the complete replacement of traditional conferences (median score 1). The most common choices for the partial replacement of tradition conferences were case conferences (59/108, 55%) and board preparation (64/108, 59%). Lastly, there was a significant difference in scores for continued use of virtual conferencing in those who attend nationally sponsored conferences (median score 5, n = 70) and those who do not (median score 4, n = 38; U = 1762.50, z = 2.97, r = 0.29, p = 0.003). CONCLUSIONS: Virtual conferences will likely remain an integral part of neurosurgical education after the COVID-19 pandemic has abated. Across the country, residents and faculty report a preference for continued use of virtual conferencing, especially virtual case conferences and board preparation. Some traditional conferences may even be replaced with virtual conferences, in particular those that are more didactic. Furthermore, nationally sponsored virtual conferences have a positive effect on the preferences for continued use of virtual conferences.

Genomic Analysis of Posterior Fossa Meningioma Demonstrates Frequent AKT1 E17K Mutations in Foramen Magnum Meningiomas.

Objective Posterior fossa meningiomas are surgically challenging tumors that are associated with high morbidity and mortality. We sought to investigate the anatomical distribution of clinically actionable mutations in posterior fossa meningioma to facilitate identifying patients amenable for systemic targeted therapy trials. Methods Targeted sequencing of clinically targetable AKT1 , SMO , and PIK3CA mutations was performed in 61 posterior fossa meningioma using Illumina NextSeq 500 to a target depth of >500 × . Samples were further interrogated for 53 cancer-relevant RNA fusions by the Archer FusionPlex panel to detect gene rearrangements. Results AKT 1 ( E17K ) mutations were detected in five cases (8.2%), four in the foramen magnum and one in the cerebellopontine angle. In contrast, none of the posterior fossa tumors harbored an SMO ( L412F ) or a PIK3CA ( E545K ) mutation. Notably, the majority of foramen magnum meningiomas (4/7, 57%) harbored an AKT1 mutation. In addition, common clinically targetable gene fusions were not detected in any of the cases. Conclusion A large subset of foramen magnum meningiomas harbor AKT1 E17K mutations and are therefore potentially amenable to targeted medical therapy. Genotyping of foramen magnum meningiomas may enable more therapeutic alternatives and guide their treatment decision process.

A new set of eyes: development of a novel microangioscope for neurointerventional surgery.

BACKGROUND: Endovascular technological advances have revolutionized the field of neurovascular surgery and have become the mainstay of treatment for many cerebrovascular pathologies. Digital subtraction angiography (DSA) is the 'gold standard' for visualization of the vasculature and deployment of endovascular devices. Nonetheless, with recent technological advances in optics, angioscopy has emerged as a potentially important adjunct to DSA. Angioscopy can offer direct visualization of the intracranial vasculature, and direct observation and inspection of device deployment. However, previous iterations of this technology have not been sufficiently miniaturized or practical for modern neurointerventional practice. OBJECTIVE: To describe the evolution, development, and design of a microangioscope that offers both high-quality direct visualization and the miniaturization necessary to navigate in the small intracranial vessels and provide examples of its potential applications in the diagnosis and treatment of cerebrovascular pathologies using an in vivo porcine model. METHODS: In this proof-of-concept study we introduce a novel microangioscope, designed from coherent fiber bundle technology. The microangioscope is smaller than any previously described angioscope, at 1.7 F, while maintaining high-resolution images. A porcine model is used to demonstrate the resolution of the images in vivo. RESULTS: Video recordings of the microangioscope show the versatility of the camera mounted on different microcatheters and its ability to navigate external carotid artery branches. The microangioscope is also shown to be able to resolve the subtle differences between red and white thrombi in a porcine model. CONCLUSION: A new microangioscope, based on miniaturized fiber optic technology, offers a potentially revolutionary way to visualize the intracranial vascular space.

Vascularized Iliac Bone Graft for Complex Closure During Spinal Deformity Surgery.

Spinal pseudarthrosis is failure of bony union across a segment where arthrodesis has been attempted. A variety of treatment approaches have been proposed to promote bony union, including use of vascularized bone graft. We report a successful application of vascularized pedicled iliac crest bone graft (ICBG) to treat recurrent lumbar and sacral pseudarthrosis. The vascularized ICBG offers the advantages of biocompatibility, mechanical stability, and minimal antigenicity. Vascularized bone transfers to the spine undergo fusion without resorption, even in the presence of compressive and rotatory forces. With its ease of access within the operative field and limited donor site morbidity, vascularized ICBG is an ideal orthobiologic that expedites time to bony union.