Search

Background and Objective: Iatrogenic spinal durotomies occur at a rate of 1% to 17%. Surgical simulation for durotomy repair is needed to provide affordable, accessible, and validated practice. This study sought to design and validate a simple 3-dimensional printed model for spinal cerebrospinal fluid (CSF) leak repair and to introduce the Rochester original objective structured assessment of technical skills (OSATS) CSF leak (ROCL) repair criteria for assessment., Methods: A spinal model was designed to mimic a lumbar laminectomy with the L3-5 lamina removed and 3-dimensional printed using Vero polymers. The model was paired with a porcine collagen "dura" that was pressurized using IV saline and overlayed with gel-molded fascial, muscle, and skin layers with an opening. Participants were provided a training model with a 1.5-cm midline durotomy, surgical microinstrument set, microscope, and 6-0 prolene suture. The 25-point ROCL repair criteria were adapted from the original OSATS principles to assess proficiency in surgical repair by 2 blinded neurosurgeons not participating in the trials. Postsimulation survey data regarding model realism were collected., Results: Six residents and 4 attendings participated. Median operative time in minutes was 13 minutes among residents and 7 minutes among attendings. Moreover, the ROCL score was a median of 19/25 for attendings and 15/25 for residents. The suture angle was statistically more consistent among senior residents and attendings compared with junior residents. Participants agreed that the model was realistic (median 4/5), useful for improving the operative technique (median 5/5), and would increase comfort in spinal CSF leak repair procedures (median 5/5). Each reusable model had a cost of $19.99 if printed with polylactic acid and each replacement dura cost <3¢., Conclusion: This study presents an affordable, realistic, and educational spinal CSF leak repair model and introduces ROCL for assessment., (Copyright © Congress of Neurological Surgeons 2024. All rights reserved.)

Background and Objectives: Predicting functional outcomes after surgical management of ruptured aneurysms is essential. This study sought to validate the modified Southwestern Aneurysm Severity Index (mSASI), which predicts functional outcomes 1 year after treatment., Methods: The surgical arm of a randomized controlled trial, the Barrow Ruptured Aneurysm Trial, was used to validate the mSASI model. mSASI scores incorporating the Hunt and Hess scale, Non-Neurological American Society of Anesthesiologists Physical Classification Status, imaging findings, and other modifiers were assigned and evaluated against the Glasgow Outcome Scale (GOS) score at 1 year. The model's performance was assessed for discrimination and calibration. Similar evaluations were constructed using the modified Rankin Scale (mRS) as the 1-year functional outcome measurement. Long-term outcomes (3, 6, 10 years) were also evaluated., Results: Of 280 clinical trial patients treated surgically, 242 met the inclusion criteria. The mean age was 54.1 ± 12.9 years; 31% were men. Favorable GOS score (4-5) and mRS score (0-2) at 1 year were observed in 73.6% and 66.1% of patients, respectively. The mSASI model predicted unfavorable GOS score at 1 year with fair to good discrimination (area under the curve = 0.75, 95% CI = 0.68-0.82) and accurate calibration (R 2 = 0.98). Similar results were obtained when mRS was used as the outcome measure (area under the curve = 0.75, 95% CI = 0.68-0.82; R 2 = 0.95)., Conclusion: The mSASI model was externally validated in our cohort to predict functional outcomes using the GOS or mRS scores 1 year after surgery. This index may be used for prognosticating outcomes of patients undergoing surgery for ruptured aneurysms at short-term and long-term intervals., (Copyright © Congress of Neurological Surgeons 2024. All rights reserved.)

In a period when the budding field of neurosurgery was believed to have little promise, Dr Alfred Washington Adson founded and led the first neurosurgical department at Mayo Clinic. He was not without reservations-surgical intervention for neurological conditions was rarely pursued because of poor outcomes and high complication rates, and Dr Adson acknowledged his early concerns about the future of neurosurgery in his memoirs. However, his education, mentorship, his training, and his first neurosurgical cases helped to shape the impact he ultimately had on the field and his legacy as a neurosurgeon. Dr Adson trained with several renowned Mayo general surgeons, notably his mentor Dr Emil Beckman, whose desire for operative precision shaped Dr Adson's drive to develop his own skills as a surgeon. Two years into his residency, he became the youngest staff surgeon and was tasked with managing the neurosurgical cases at Mayo. The five neurosurgical cases overseen by Dr Adson in the next year illuminated the opportunity for neurosurgery to drastically improve the lives of patients. Dr Adson, given the option of continuing as either a general surgeon or a neurosurgeon, ultimately chose to pursue neurosurgery. This article seeks to provide a historical perspective on the neurosurgeon Dr Alfred Washington Adson using primary and secondary accounts from the Mayo archives, highlighting his contributions to the early understanding of intracranial pathology and how his early experiences as a trainee developed into a personal passion for self-improvement, education, and advocacy for health care in America., (Copyright © Congress of Neurological Surgeons 2023. All rights reserved.)

Background and Objective: As incidence of operative spinal pathology continues to grow, so do the rates of lumbar spinal fusion procedures. Comorbidity indices can be used preoperatively to predict potential complications. However, there is a paucity of research defining the optimal comorbidity indices in patients undergoing spinal fusion surgery. We aimed to use modeling strategies to evaluate the predictive validity of various comorbidity indices and combinations thereof., Methods: Patients who underwent spinal fusion were queried using data from the Nationwide Readmissions Database for the years 2016 through 2019. Using comorbidity indices as predictor variables, receiver operating characteristic curves were developed for pertinent complications such as mortality, nonroutine discharge, top-quartile cost, top-quartile length of stay, and 30-day readmission., Results: A total of 750 183 patients were included. Nonroutine discharges occurred in 161 077 (21.5%) patients. The adjusted all-payer cost for the procedure was $37 616.97 ± $27 408.86 (top quartile: $45 409.20), and the length of stay was 4.1 ± 4.4 days (top quartile: 8.1 days). By comparing receiver operating characteristics of various models, it was found that models using Frailty + Elixhauser Comorbidity Index (ECI) as the primary predictor performed better than other models with statistically significant P -values on post hoc testing. However, for prediction of mortality, the model using Frailty + ECI was not better than the model using ECI alone ( P = .23), and for prediction of all-payer cost, the ECI model outperformed the models using frailty alone ( P < .0001) and the model using Frailty + ECI ( P < .0001)., Conclusion: This investigation is the first to use big data and modeling strategies to delineate the relative predictive utility of the ECI and Johns Hopkins Adjusted Clinical Groups comorbidity indices for the prognostication of patients undergoing lumbar fusion surgery. With the knowledge gained from our models, spine surgeons, payers, and hospitals may be able to identify vulnerable patients more effectively within their practice who may require a higher degree of resource utilization., (Copyright © Congress of Neurological Surgeons 2023. All rights reserved.)

Background and Objectives: Preoperative embolization of arteriovenous malformations (AVMs) remains controversial. This study sought to analyze the cost-effectiveness of preoperative embolization of AVMs., Methods: Patients who underwent AVM resection at a single institute (January 1, 2015-December 31, 2020) were analyzed. Patients with preoperative embolization (embolization cohort) were compared with those without preoperative embolization (nonembolization cohort). Cost-effectiveness score (CE) was the primary outcome of interest and was determined by dividing the total 1-year cost by effectiveness, which was derived from a validated preoperative to last follow-up change in the modified Rankin Scale utility score. A lower CE signifies a more cost-effective treatment strategy., Results: Of 188 patients, 88 (47%) underwent preoperative embolization. The mean (SD) total cost was higher in the embolization group than in the nonembolization group ($117 594 [$102 295] vs $84 348 [$82 326]; P < .001). The mean (SD) CE was higher in the embolization cohort ($336 476 [$1 303 842]) than in the nonembolization cohort ($100 237 [$246 255]; P < .001). Among patients with Spetzler-Martin (SM) grade I and II AVMs, the mean (SD) CE was higher in the embolization (n = 40) than in the nonembolization (n = 72) cohort ($164 950 [$348 286] vs $69 021 [$114 938]; P = .004). Among patients with SM grade III AVMs, the mean (SD) CE was lower in the embolization (n = 33) than in the nonembolization (n = 25) cohort ($151 577 [$219 130] vs $189 195 [$446 335]; P = .006). The mean (SD) CE was not significantly different between cohorts among patients with higher-grade AVMs (embolization cohort [n = 3] vs nonembolization cohort [n = 15]: $503 639 [$776 492] vs $2 048 419 [$4 794 758]; P = .49). The mean CE for embolized SM grade III aneurysms was nonsignificant in the ruptured group; however, for the unruptured group, CE was significantly higher in the embolization cohort (n = 26; $160 871 [$240 535]) relative to the nonembolization cohort (n = 15; $108 152 [$166 446]) ( P = .006)., Conclusion: Preoperative embolization was cost-effective for patients with SM grade III AVMs but not for patients with lower-grade AVMs., (Copyright © Congress of Neurological Surgeons 2023. All rights reserved.)

Background and Objectives: Basilar artery fenestration is a rare phenomenon sometimes associated with basilar artery fenestration aneurysms (BAFAs). This review investigates the natural history and management outcomes of BAFAs and describes the outcomes of BAFAs treated with embolization., Methods: A single-center database was queried for all cases of endovascular BAFA treatment. Data on complications, clinical and angiographic outcomes, and retreatment rates were collected., Results: Seventeen aneurysms across 17 patients were treated. The mean (SD) age was 56 (13) years, and 15 (88%) patients were women. Among 15 aneurysms with data available, 2 arose from the fenestration limbs and 13 from both limbs and the vertebral artery. Of 16 aneurysmal projections available, 7 projected anteriorly, 7 posteriorly, and 2 superiorly. Among 17 patients, balloon-assisted coiling was the most common treatment (n = 10), followed by primary coiling (n = 3), stent-assisted coiling (n = 2), coiling with flow diversion (n = 1), and balloon-assisted coiling and flow diversion (n = 1). Complications noted in 5 patients included hemorrhage, thromboembolism, paresthesias, vasospasm, and transient hemiparesis. Among 16 patients with postoperative results available, 12 showed favorable clinical outcomes, 3 were disabled, and 1 died. The rates of postoperative complete (Raymond-Roy Occlusion Classification 1) and incomplete (Raymond-Roy Occlusion Classification 2 and 3) occlusion among 15 patients with available data were 6 and 9, respectively., Conclusion: Endovascular management of these rare aneurysms is feasible and safe, with high rates of favorable radiographic and clinical outcomes. This series reflects a general preference toward coiling and stent-assisted coiling, although flow diversion may be considered in select cases., (Copyright © Congress of Neurological Surgeons 2023. All rights reserved.)

Pontine arteriovenous malformations (AVMs) are uncommon lesions, with few reports in the literature. The best treatment option is debated, with options including surgical resection, endovascular embolization, and radiosurgery. Patient consent for the procedure was obtained. Herein, we report the successful resection of a ruptured lateral pontine AVM with an associated aneurysm in a woman in her early 70s. Surgical resection can be considered an effective treatment option for brainstem AVMs and should be considered alone or in conjunction with other treatment modalities. Used with permission from Barrow Neurological Institute, Phoenix, Arizona., (© Congress of Neurological Surgeons 2021.)

Dissecting fusiform posterior inferior cerebellar artery (PICA) aneurysms are rare and challenging.1,2 One common treatment is occlusion of the aneurysm and parent artery via an endovascular approach without revascularization.3 Revascularization of the artery requires an open microsurgical bypass or endovascular placement of a newer-generation flow diverter.4 We present an end-to-side reanastomosis of the PICA for treatment of a dissecting fusiform left PICA aneurysm with anatomy deemed unfavorable for endovascular treatment in a 62-yr-old man with subarachnoid hemorrhage. After discussions regarding risks, benefits, and alternatives to the procedure, the family consented to surgical treatment.  A far-lateral craniotomy was performed, with partial condylectomy to widen the exposure. The cisterna magna was opened, and the dentate ligament was cut to visualize the vertebral artery. The PICA was identified and traced distally to the aneurysmal segment, which was circumferentially diseased. Perforators were noted immediately distal to the aneurysm. The aneurysm was then trapped, and the afferent artery was transected and brought to the sidewall of the distal artery. The recipient site was trapped with temporary clips, and a linear arteriotomy was made. An end-to-side reanastomosis was performed, temporary clips were removed, and hemostasis was achieved. Postoperative angiography confirmed bypass patency and preservation of the PICA perforators.  Conventional reanastomosis of the parent artery after aneurysm excision is achieved by end-to-end reanastomosis. In contrast, we performed an unconventional end-to-side reanastomosis to revascularize the PICA while leaving the efferent artery in situ to protect its medullary perforators. This bypass is an example of a fourth-generation bypass.5,6 Used with permission from the Barrow Neurological Institute, Phoenix, Arizona., (© Congress of Neurological Surgeons 2021.)

Giant basilar apex aneurysms are associated with significant therapeutic challenges.1-6 Multiple techniques exist to treat giant basilar apex aneurysms, including direct clipping, stent-assisted coil embolization, and proximal occlusion with bypass revascularization.7-9 Hypothermic circulatory arrest was a useful adjunct for surgical repair of these aneurysms but has been abandoned because of associated risks.10,11 Rapid ventricular pacing can achieve similar aneurysm softening with minimal risks and assist in clip occlusion. This case illustrates clip occlusion of a giant, partially thrombosed, previously stent-coiled basilar apex aneurysm in a 15-yr-old boy with progressive cranial neuropathies and sensorimotor impairment. Although a wire was placed preoperatively for ventricular pacing, it was not needed during the procedure. Patient consent was obtained. A right-sided orbitozygomatic craniotomy transcavernous approach with anterior and posterior clinoidectomies was performed. The basilar quadrification was dissected, and proximal control was obtained. After aneurysm trapping, the aneurysm was incised and thrombectomized using an ultrasonic aspirator. Back-bleeding from the aneurysm was anticipated, and ventricular pacing was ready, but back-bleeding was minimal. With the coil mass left in place, stacked, fenestrated clips were applied in a tandem fashion to occlude the aneurysm neck. Indocyanine green videoangiography confirmed occlusion of the aneurysm and patency of parent and branch arteries. The patient was at a neurological baseline after the operation, with improvement in motor skills and cognition at 3-mo follow-up. This case demonstrates the use of trans-sylvian-transcavernous exposure, rapid ventricular pacing, and thrombectomy amid previous coils and stents to clip a giant, thrombotic basilar apex aneurysm. Used with permission from Barrow Neurological Institute, Phoenix, Arizona., (© Congress of Neurological Surgeons 2021.)

Adolescent idiopathic scoliosis (AIS) is an abnormal lateral curvature of the spine that arises during the pubescent growth spurt. AIS mainly affects females in the age group of 10 to 16 yr, with a prevalence of about 1% to 3% in the at-risk population.1 Treatment options vary depending on disease presentation and severity. Mild curvature mainly requires periodic observation for disease progression, whereas more moderate curvature can necessitate bracing or corrective surgery.2 Here, we present the use of a temporary rod and neuroimaging for the correction of Lenke type 1 spinal curvature in an AIS patient. An inferior facetectomy is performed, and a Lenke probe is used for entry into the pedicle and vertebral body. The channel is sounded before and after tapping to check for adequate walls prior to insertion of the pedicle screw. The ARTIS pheno is brought into the field, which uses fluoroscopy to create a 3-dimensional (3D) representation of the instrumentation within the spine. A temporary rod is placed in the concavity, and a combination of corrective techniques, including a rod roll, apical translation, and reduction, is performed to bring up the concavity, derotate the spine, and translate the spine. The permanent rod is then placed in the convexity, and compression is performed to bring down the scapular prominence. The temporary rod is then removed, and a final rod is placed to complete the 3D correction. The patient consented to the procedure, and an informed written consent was obtained from the patient to use her photographs and video recordings for publication., (© Congress of Neurological Surgeons 2021.)