Faculty Bibliography

OBJECTIVE:An increasing number of obese patients undergoing elective spine surgery has been reported. Obesity has been associated with a substantially higher number of surgical site infections and a longer surgery duration. However, there is a lack of research investigating the intersection of obesity and full endoscopic spine surgery (FESS) in terms of functional outcomes and complications. The aim of this study was to evaluate wound site infections and functional outcomes following FESS in obese patients. METHODS:Patients undergoing lumbar FESS at the participating institutions from March 2020 to March 2023 for degenerative pathologies were included in the analysis. Patients were divided into obese (BMI > 30 kg/m2) and nonobese (BMI 18-30 kg/m2) groups. Data were collected prospectively using an approved smartphone application for 3 months postsurgery. Parameters included demographics, surgical details, a virtual wound checkup, the visual analog scale for back and leg pain, and the Oswestry Disability Index (ODI) as a functional outcome measure. RESULTS:A total of 118 patients were included in the analysis, with 53 patients in the obese group and 65 in the nonobese group. Group homogeneity was satisfactory regarding patient age (obese vs nonobese: 55.5 ± 14.7 years vs 59.1 ± 17.1 years, p = 0.25) and sex (p = 0.85). No surgical site infection requiring operative revision was reported for either group. No significant differences for blood loss per level (obese vs nonobese: 9.7 ± 16.8 ml vs 8.0 ± 13.3 ml, p = 0.49) or duration of surgery per level (obese vs nonobese: 91.2 ± 57.7 minutes vs 76.8 ± 39.2 minutes, p = 0.44) were reported between groups. Obese patients showed significantly faster improvement regarding ODI (-3.0 ± 9.8 vs 0.7 ± 11.3, p = 0.01) and leg pain (-4.4 ± 3.2 vs -2.9 ± 3.7, p = 0.03) 7 days postsurgery. This effect was no longer significant 90 days postsurgery for either ODI (obese vs nonobese: -11.4 ± 11.4 vs -9.1 ± 9.6, p = 0.24) or leg pain (obese vs nonobese: -4.3 ± 3.9 vs -3.5 ± 3.8, p = 0.28). CONCLUSIONS:The results highlight the effectiveness and safety of lumbar FESS in obese patients. Unlike with open spine surgery, obese patients did not experience significant increases in surgery time or postoperative complications. Interestingly, obese patients demonstrated faster early recovery, as indicated by significantly greater improvements in ODI and leg pain at 7 days after surgery. However, there was no difference in improvement between the groups at 90 days after surgery.

BACKGROUND/UNASSIGNED:Previous research on spinal alignment and postoperative outcomes after cervical and upper thoracic fixation has suggested that clinical and patient-reported outcomes are improved when certain anatomical parameters are maintained. These parameters include the cervical sagittal vertical axis (cSVA), C2 and T1 slopes, and cervical lordosis (CL). For patients with primary and metastatic tumors involving the subaxial cervical and/or upper thoracic spine, there is minimal guidance on how to apply these parameters. Surgeons must make critical decisions when designing the optimal construct, considering patient life expectancy, bone quality, oncology goals and deformity. This study aims to evaluate the impact of cervical spine alignment parameters on postoperative hardware failure in spine tumor patients and highlight instances of complications in patients with instrumentation crossing the cervicothoracic junction (CTJ). METHODS/UNASSIGNED:A retrospective review of a single institutional spine tumor database identified seventeen patients who underwent spinal fusion crossing the CTJ from 2015 to 2023. All patients had postoperative neutral standing radiographs with measurable cSVA, C2 and T1 slopes, and/or CL. The primary endpoint was instrumentation failure, defined as hardware pull out or breakage, and secondary endpoints included other complications including wound infection and spinal fluid leak. RESULTS/UNASSIGNED:=2). The mean cSVA was 3.39±1.02 cm (range 1.59-4.9 cm). Fourteen patients had measurable C2 slopes with a mean of 25.03±9.16° (range 8.7 - 38.6°). Ten patients had measurable T1 slopes with a mean of 31.5±11.54° (range 18.4-59.6°). Thirteen patients had a measurable CL with a mean of 9.13±9.93° (range 0-37.5°). No cases of instrumentation failure were noted. Four patients experienced other postoperative complications (24%), but rates did not vary with increasing deviation from ideal parameters for cSVA, C2 and T1 slope, or CL. CONCLUSIONS/UNASSIGNED:Although there was wide variability in alignment parameters in this cohort, there were no instances of hardware failure with crossing the CTJ at a mean follow-up of 41 months. The overall complication rate was high at 24%. Despite common concerns about the impact of exaggerated slope and SVA on instrumentation failure these results suggest that cervical and upper thoracic tumor patients may still have a satisfactory result following CTJ fixation, even with unfavorable alignment parameters. Larger prospective studies are needed.

OBJECTIVE:To establish whether or not a natural language processing technique could identify two common inpatient neurosurgical comorbidities using only text reports of inpatient head imaging. MATERIALS AND METHODS/METHODS:A training and testing dataset of reports of 979 CT or MRI scans of the brain for patients admitted to the neurosurgery service of a single hospital in June 2021 or to the Emergency Department between July 1-8, 2021, was identified. A variety of machine learning and deep learning algorithms utilizing natural language processing were trained on the training set (84% of the total cohort) and tested on the remaining images. A subset comparison cohort (n = 76) was then assessed to compare output of the best algorithm against real-life inpatient documentation. RESULTS:For "brain compression", a random forest classifier outperformed other candidate algorithms with an accuracy of 0.81 and area under the curve of 0.90 in the testing dataset. For "brain edema", a random forest classifier again outperformed other candidate algorithms with an accuracy of 0.92 and AUC of 0.94 in the testing dataset. In the provider comparison dataset, for "brain compression," the random forest algorithm demonstrated better accuracy (0.76 vs 0.70) and sensitivity (0.73 vs 0.43) than provider documentation. For "brain edema," the algorithm again demonstrated better accuracy (0.92 vs 0.84) and AUC (0.45 vs 0.09) than provider documentation. DISCUSSION/CONCLUSIONS:A natural language processing-based machine learning algorithm can reliably and reproducibly identify selected common neurosurgical comorbidities from radiology reports. CONCLUSION/CONCLUSIONS:This result may justify the use of machine learning-based decision support to augment provider documentation.

Despite the importance of informed consent in healthcare, the readability and specificity of consent forms often impede patients' comprehension. This study investigates the use of GPT-4 to simplify surgical consent forms and introduces an AI-human expert collaborative approach to validate content appropriateness. Consent forms from multiple institutions were assessed for readability and simplified using GPT-4, with pre- and post-simplification readability metrics compared using nonparametric tests. Independent reviews by medical authors and a malpractice defense attorney were conducted. Finally, GPT-4's potential for generating de novo procedure-specific consent forms was assessed, with forms evaluated using a validated 8-item rubric and expert subspecialty surgeon review. Analysis of 15 academic medical centers' consent forms revealed significant reductions in average reading time, word rarity, and passive sentence frequency (all P < 0.05) following GPT-4-faciliated simplification. Readability improved from an average college freshman to an 8th-grade level (P = 0.004), matching the average American's reading level. Medical and legal sufficiency consistency was confirmed. GPT-4 generated procedure-specific consent forms for five varied surgical procedures at an average 6th-grade reading level. These forms received perfect scores on a standardized consent form rubric and withstood scrutiny upon expert subspeciality surgeon review. This study demonstrates the first AI-human expert collaboration to enhance surgical consent forms, significantly improving readability without sacrificing clinical detail. Our framework could be extended to other patient communication materials, emphasizing clear communication and mitigating disparities related to health literacy barriers.

BACKGROUND:Our objective is to describe a minimally invasive endoscopic surgical technique for performing lateral lumbar interbody fusion (LLIF). LLIF is a common approach to lumbar fusion in cases of degenerative lumbar disease; however, complications associated with psoas and lumbar plexus injury sometimes arise. The endoscopic modification presented here diminishes the requirement for sustained muscle retraction, minimizing complication risk while allowing for adequate decompression in select cases. METHODS:Endoscopic LLIF (ELLIF) was performed in 3 patients from 2019 to 2021. Surgeries were performed in the lateral position under general anesthesia with neurophysiological monitoring. Discectomy, endplate preparation, and harvesting of iliac crest bone were performed through a working channel endoscope. The introduction of an interbody cage (Joimax EndoLIF) was performed over a nitinol blunt-tip wire (Joimax). No expandable blade retractors were required. RESULTS:At 2-year follow-up of these 3 patients, the mean visual analog scale (VAS) score for leg pain improved from 9.3 to 1.7, and the mean Oswestry Disability Index (ODI) score improved from 40 to 8.3. There were no complications, readmissions, or recurrence of symptoms during the 2-year follow-up period. Patients spent an average of 36 hours in the hospital postoperatively and returned to normal daily activities after an average of 48 days. CONCLUSIONS:A minimally invasive modification to the LLIF procedure is presented that offers several potential advantages due to the application of endoscopic techniques: reduced muscle retraction, smaller incision, and the opportunity to perform both indirect decompression and endoscopically visualized discectomy in the same fusion procedure. CLINICAL RELEVANCE/CONCLUSIONS:The proposed endoscopic lateral lumbar interbody fusion and decompression is a minimally invasive technique that may provide patients with minimal complications, quick recovery, and good functional recovery.

BACKGROUND/UNASSIGNED:Historically, the readability of consent forms in medicine have been above the average reading level of patients. This can create challenges in obtaining truly informed consent, but the implications on clinical trial participant retention are not fully explored. To address this gap, we seek to analyze clinical trial consent forms by determining their readability and relationship with the associated trial's participant dropout rate. Additionally, we explore a potential method for simplifying these forms. METHODS/UNASSIGNED:We analyzed the readability of consent forms of federally funded interventional clinical trials, which were completed in the United States on or before January 1, 2023, and were posted online and made accessible on ClinicalTrials.gov. We correlated their readability with trial dropout rates. As an exploratory analysis, a subset of these forms was simplified using a large language model, with expert medicolegal review. FINDINGS/UNASSIGNED:Across 798 included federally funded trials, the mean (±SD) Flesch-Kincaid Grade Level of their consent forms was 12.0 ± 1.3, equivalent to a high school graduate reading level and significantly higher than the 8th grade average reading level of adults in the United States (U.S.) (P < 0.001). In risk-adjusted analyses, each additional Flesch-Kincaid Grade Level increase in a clinical trial's consent form was associated with a 16% higher dropout rate (incidence rate ratio, 1.16; 95% confidence interval, 1.12-1.22; P < 0.001). Our exploratory analysis of a simplification method showed promising results in lowering the reading level while preserving medicolegal content. INTERPRETATION/UNASSIGNED:The average readability of informed consent forms of federally funded clinical trials exceeds the reading comprehension skills of the majority of adults in the U.S., potentially undermining clinical trial participant retention rates. Future work should explore the use of large language models and other tools as possible means to close this literacy barrier and potentially enhancing clinical trial participation. FUNDING/UNASSIGNED:This research received no sources of funding. The authors have no conflicts of interest to report.

BACKGROUND AND OBJECTIVES/OBJECTIVE:Glucagon-like peptide-1 receptor agonists (GLP-1 RAs) have gained increasing popularity since the approval of semaglutide by the United States Food and Drug Administration for chronic weight management. Significant benefits have been noted in glycemic control and cardiovascular health. However, as increasing numbers of patients are started on these medications, it is important for neurosurgeons to have knowledge of any perioperative considerations and side effects related to this class of drugs. METHODS:We performed a qualitative literature review using the PubMed and Embase databases, using the following key words: GLP-1 RAs adverse events; GLP-1 RAs and anesthesia; substance use disorders; and addiction, functional neurosurgery, nervous system rehabilitation, and spinal cord injury. Articles of relevance to perioperative management of these medications and specific benefits in the neurosurgical field were discussed. RESULTS:Recent guidance from the American Society of Anesthesiologists demonstrates the importance of tailored management of GLP-RA drugs for surgical patients. In addition, certain positive effects have been noted with relation to substance use disorders, neural protection and rehabilitation, and neurodegenerative disorders such as Alzheimer's disease. CONCLUSION/CONCLUSIONS:In this article, we review what the neurosurgeon needs to know about the perioperative management of GLP-1 RAs and discuss existing literature in clinical and preclinical studies for potential indications and benefits of these medications, which can influence the management of conditions treated by neurosurgeons.

It can be said that the specialty of neurosurgery in Iceland had its beginnings on November 30, 1971, with the arrival of a huge American C-130 Hercules aircraft. It was carrying a small package containing Scoville aneurysm clips. They were sent to the late Bjarni Hannesson (1938-2013), who had received his neurosurgical training in 1967-1971 at the Dartmouth-Hitchcock Medical Center (then known as Mary Hitchcock Memorial Hospital and located in Hanover, New Hampshire). He used one to clip the right posterior communicating artery aneurysm of a 34-year-old fisherman, who recovered well. The apparent reason for the use of such a huge aircraft for such a small payload is to be found in the sociocultural politics of the Cold War. It involved the continued presence of the American base at Keflavík, where the C-130 landed. The base was under pressure to be closed by Iceland's left-leaning, nominally communist government. The C-130's arrival generated welcome publicity for the continued operation of the American base, which is still there.

OBJECTIVE:Questions regarding anticipated pain improvement and functional recovery postsurgery are frequently posed in preoperative consultations. However, a lack of data characterizing outcomes for the first postoperative days only allows for anecdotal answers. Hence, the assessment of ultra-early patient-reported outcome measures (PROMs) is essential for patient-provider communication and patient satisfaction. The aim of this study was to elucidate this research gap by assessing and characterizing PROMs for the first days after full endoscopic spine surgery (FESS). METHODS:This multicenter study included patients undergoing lumbar FESS from March 2021 to July 2023. After informed consent was provided, data were collected prospectively through a smartphone application. Patients underwent either discectomy or decompression. Analyzed parameters included demographics, surgical details, visual analog scale scores for both back and leg pain, and the Oswestry Disability Index (ODI) score. Data were acquired daily for the 1st postoperative week, as well as after 2 weeks, 3 months, and 6 months. RESULTS:A total of 182 patients were included, of whom 102 underwent FESS discectomy and 80 underwent FESS decompression. Significant differences between the discectomy and decompression groups were found for age (mean 50.45 ± 15.28 years and 63.85 ± 13.25 years, p < 0.001; respectively), sex (p = 0.007), and surgery duration (73.45 ± 45.23 minutes vs 98.05 ± 46.47 minutes, p < 0.001; respectively). Patients in both groups reported a significant amelioration of leg pain on the 1st postoperative day (discectomy group VAS score: 6.2 ± 2.6 vs 2.4 ± 2.9, p < 0.001; decompression group: 5.3 ± 2.8 vs 1.9 ± 2.2, p < 0.001) and of back pain within the 1st postoperative week (discectomy group VAS score: 5.5 ± 2.8 vs 2.8 ± 2.2, p < 0.001; decompression group: 5.2 ± 2.7 vs 3.1 ± 2.4, p < 0.001). ODI score improvement was most pronounced at the 3-month time point (discectomy group: 21.7 ± 9.1 vs 9.3 ± 9.1, p < 0.001; decompression group: 19.3 ± 7.8 vs 9.9 ± 8.3, p < 0.001). For both groups, pain improvement within the 1st week after surgery was highly predictive of later benefits. CONCLUSIONS:Ultra-early PROMs reveal an immediate pain improvement after FESS. While the benefits in pain reduction plateaued within the 1st postoperative week for both groups, functional improvements developed over a more extended period. These results illustrate a biphasic rehabilitation process wherein initial pain alleviation transitions into functional improvement over time.