Faculty Bibliography

BACKGROUND AND OBJECTIVES/OBJECTIVE:Scholarly output is accelerating in medical domains, making it challenging to keep up with the latest neurosurgical literature. The emergence of large language models (LLMs) has facilitated rapid, high-quality text summarization. However, LLMs cannot autonomously conduct literature reviews and are prone to hallucinating source material. We devised a novel strategy that combines Reference Publication Year Spectroscopy-a bibliometric technique for identifying foundational articles within a corpus-with LLMs to automatically summarize and cite salient details from articles. We demonstrate our approach for four common spinal conditions in a proof of concept. METHODS:Reference Publication Year Spectroscopy identified seminal articles from the corpora of literature for cervical myelopathy, lumbar radiculopathy, lumbar stenosis, and adjacent segment disease. The article text was split into 1024-token chunks. Queries from three knowledge domains (surgical management, pathophysiology, and natural history) were constructed. The most relevant article chunks for each query were retrieved from a vector database using chain-of-thought prompting. LLMs automatically summarized the literature into a comprehensive narrative with fully referenced facts and statistics. Information was verified through manual review, and spine surgery faculty were surveyed for qualitative feedback. RESULTS:Our tandem approach cost less than $1 for each condition and ran within 5 minutes. Generative Pre-trained Transformer-4 was the best-performing model, with a near-perfect 97.5% citation accuracy. Surveys of spine faculty helped refine the prompting scheme to improve the cohesion and accessibility summaries. The final artificial intelligence-generated text provided high-fidelity summaries of each pathology's most clinically relevant information. CONCLUSION/CONCLUSIONS:We demonstrate the rapid, automated summarization of seminal articles for four common spinal pathologies, with a generalizable workflow implemented using consumer-grade hardware. Our tandem strategy fuses bibliometrics and artificial intelligence to bridge the gap toward fully automated knowledge distillation, obviating the need for manual literature review and article selection.

BACKGROUND:There is a paucity of data on treatment outcomes following stereotactic radiosurgery (SRS) for brain metastases from sarcoma primaries. METHODS:The International Radiosurgery Research Foundation member-sites were queried for patients with brain metastases from sarcoma primaries treated with SRS. Overall survival (OS) and local control (LC) were calculated via Kaplan-Meier analysis. Univariate analyses examined prognostic factors associated with LC and OS via log-rank t-tests and multivariate analyses (MVA) via Cox proportional hazards model. RESULTS:A total of 146 patients with 309 brain metastases were identified. Two-hundred and thirty lesions were treated with single-fraction SRS with a median dose of 20 Gy (15-24 Gy). Ninety-five patients had extracranial metastases, including 75 oligometastatic patients. One- and 2-year OS and LC rates were 47.7% and 37.3%, and 78.3% and 62.2%, respectively. On univariate analyses, superior 1-year OS was noted among leiomyosarcomas (69.7% vs. 42.6%; p = .02) with poorer outcomes among pleomorphic histologies (10.5% vs. 50.7%; p = .002). Pleomorphic histologies were associated with poorer OS on MVA (hazard ratio [HR], 3.13; p = .006). On MVA, LC was inferior among patients of age ≥45 years (HR, 3.78; p < .001) and superior among leiomyosarcomas (HR, 0.31; p = .03). OS was prognosticated based on adverse factors (ie, nonleiomyosarcoma histology and progressive extracranial metastases). Two-year OS for patients with and without adverse features were 78.6% and 31.5%, respectively. CONCLUSIONS:LC outcomes were driven by histology and age with superior LC among leiomyosarcomas and patients of age <45 years. OS was driven by nonleiomyosarcoma histology and the presence of progressive extracranial disease.

BACKGROUND:Given the low haemorrhagic risk of intracranial low-grade dural arteriovenous fistulas (dAVFs), the benefits of routine intervention remain controversial. This study compares patient outcomes treated with stereotactic radiosurgery (SRS) versus conservative management. METHOD/METHODS:Multicentre retrospective analysis of the Consortium for Dural Arteriovenous Fistula Outcomes Research and the International Radiosurgery Research Foundation data. Inclusion criteria were (1) intracranial low-grade dAVF diagnosed by catheter-based angiography, (2) no prior dAVF-related haemorrhage and (3) management with upfront SRS (intervention group) or conservative management (observation group). The primary outcome was symptomatic improvement. Secondary outcomes included dAVF obliteration, up-conversion, haemorrhage, improvement and favourable modified Rankin Scale (mRS) at follow-up. RESULTS:304 patients with a mean age of 56 years (SD 13.5) and a follow-up of 46.7 months (SD 45.5) were included. 135 (44.4%) were managed conservatively and 169 (55.6%) had upfront SRS. Compared with the observation group, symptomatic and mRS Score improvement (≥1-point decrease in baseline score) was more likely in the intervention group (95.1% vs 58.5%; OR=13.75 (5.61-33.69) and 37.0% vs 24.0%; OR=1.85 (1.09-3.15), respectively). These findings remained significant after multiple imputation and propensity score matching. Remaining outcomes were similar between groups. The all-cause mortality rate was 5.4% (n=16), unrelated to the dAVF or treatment. Five (3.0%) SRS-related complications were reported and resolved during the follow-up period. CONCLUSIONS:SRS was associated with increased symptomatic and mRS Score improvement for low-grade dAVFs compared with conservative management. SRS had a low complication risk and did not appear to alter dAVF obliteration or haemorrhage. Future prospective trials on SRS as a first-line intervention for symptomatic low-grade dAVFs should be considered.

BACKGROUND:Pituitary metastases (PM) account for 0.4% of all intracranial metastases and typically present with visual and endocrinological deficits. Stereotactic radiosurgery (SRS) has shown excellent tumor control and safety profile in the management of intracranial metastases. However, its role and safety in managing metastases to the pituitary gland are not well-characterized. This study aims to evaluate SRS outcomes and safety profile in the management of PM in a multicenter international cohort. METHODS:The authors retrospectively analyzed data from 63 patients with PM treated with SRS across 12 institutions, assessing clinical and radiological outcomes, including survival rates, tumor control, visual and endocrinological outcomes, and post-treatment complications. RESULTS:Among 63 patients included in the study (median tumor volume: 1.5 cc), SRS demonstrated a local tumor control rate of 93.1% at 12 months. The median survival was 25.4 months and overall survival rates of 77.6%, 65.9%, and 55.1% at 6, 12, and 18 months, respectively. In multivariate analysis, a margin dose for PM > 10 Gy emerged as an independent predictor across progression-free survival (HR: 0.20, p < 0.01), distant metastasis-free survival (HR: 0.30, p = 0.01), and overall survival. (HR: 0.15, p < 0.01). Following SRS, most patients showed stable or improved visual function (n = 17/18). A small percentage of patients experienced complications: developed new visual deficits (n = 1/63), experienced new anterior pituitary hormone deficiency (n = 5/63), and developed arginine vasopressin (AVP)-deficiency post-treatment (n = 2/63). CONCLUSION/CONCLUSIONS:SRS is an important modality in the management of PM, offering excellent local tumor control and survival outcomes with minimal morbidity. These findings support the incorporation of SRS into the multidisciplinary management for treating patients with PM.

Seizures occur in 20-45% of patients with cerebral arteriovenous malformations (AVMs) and can potentially influence their quality of life. Some studies have suggested risk factors influencing their development, but the evidence is limited to small cohorts. To analyze seizure presentation and factors influencing seizure development in patients with cerebral AVMs using a multi-institutional consortium. Retrospective multicenter registry from multiple centers in North America and Europe of patients aged 1 to 89 years who had undergone any intervention for brain AVMs between January 2010 and December 2023. Demographics, functional assessment (modified Rankin Scale; mRS), and AVM characteristics, were evaluated to assess for relationship with seizures using a multivariate generalized linear mixed-effects model. 1,005 AVM patients were analyzed; the median age was 42, 73% had a baseline mRS ≤ 2. The median nidus size was 2.2 cm, and most AVMs were Spetzler-Martin grade II (37%). Seizure was the presenting symptom in 237 patients (24%). After adjusting for significant variables, patient-specific factors associated with seizures were younger age (OR 0.99, CI95% 0.98-1), male sex (OR 1.65, CI95% 1.18-2.30), and smoking history (OR 1.69, CI95% 1.17-2.44). AVM-specific factors associated with seizures included rupture status (OR 0.42, CI95% 0.30-0.61); eloquent cortex (OR 1.61, CI95% 1.13-2.29); frontal (OR 1.54, CI95% 1.01-2.35), temporal (OR 1.93, CI95% 1.26-2.96) and parietal (OR 1.71 CI95% 1.08-2.71) location; larger nidal size (OR = 1.23, CI95% 1.08-1.39), and superficial draining vein location (OR 1.86, CI95% 1.15-3.01). In this multicenter consortium, after controlling for significant variables, the incidence of AVM-related seizures was associated with younger age, male sex, smoking history, larger AVMs, eloquent locations, and AVMs in the frontal, temporal, and parietal cortices. Conversely, rupture status, deep venous drainage, and cerebellar locations were negatively associated with seizures.

BACKGROUND:Cerebral arteriovenous malformations (AVMs) are complex vascular lesions that pose a risk for hemorrhagic stroke. The number of draining veins has recently emerged as a significant predictor of rupture risk. This multicenter study aimed to evaluate the outcomes in adult AVM patients with single versus multiple draining veins. METHODS:We conducted a retrospective analysis of 735 AVM patients from the Multicenter International Study for Treatment of Brain AVMs (MISTA) database. Patients were categorized into single draining vein (n = 430) and multiple draining veins (n = 305) groups. Logistic and linear regression models were used to assess outcomes, adjusting for baseline characteristics, including age, rupture status, Spetzler-Martin grade, and other relevant factors. RESULTS:After adjustment, no significant differences were observed in complete AVM obliteration at last follow-up between the multiple and single draining veins groups (OR: 1.1; 95 % CI: 0.72-1.93, p = 0.49) after any treatment type. Good functional outcomes at last follow-up (mRS 0-2) were similar between the two groups (OR: 1.00; 95 % CI: 0.48-2.09, p = 0.98), as were retreatment rates (OR: 1.68; 95 % CI: 0.74-3.83, p = 0.21). Ruptured AVMs were more common in the single draining vein group (52.0 % vs. 35.4 %, p < 0.001). Patients in the multiple draining vein group had lower odds of hemorrhagic complications compared to the single vein group (OR: 0.38; 95 % CI: 0.14-1.02, p = 0.05). CONCLUSION/CONCLUSIONS:Single draining vein AVMs were more likely to present with rupture, but no significant differences in obliteration rates, functional outcomes, or retreatment rates were found between the groups after adjustment. These findings suggest that while venous drainage patterns may influence initial presentation, they do not appear to affect overall treatment success or patient prognosis after any treatment type. Further studies are needed to confirm.

PURPOSE/OBJECTIVE:Bladder cancer rarely metastasizes to the brain. This study was performed to evaluate stereotactic radiosurgery (SRS) for the management of bladder cancer brain metastases. METHODS:Cases of bladder cancer brain metastases treated with SRS were collected by members of the International Radiosurgery Research Foundation (IRRF) and outcome data was analyzed for patients with at least one clinical or imaging follow-up. RESULTS:103 patients received SRS for 301 brain metastases. Median age at SRS was 68 and 73.8% of patients were male. Median KPS was 80%. Median time from primary to brain metastases diagnosis was 18 months. At the time of SRS, 50% of patients had other systemic metastases. The median number of metastases treated was 1, and median cumulative SRS volume was 1.16 cc. Most patients had single fraction SRS using a median margin dose of 18 Gy. At the time of analysis, 9.7% of patients were alive. Median survival after SRS was 7 months. Local control was achieved for 89.3% of metastases, 42% of patients developed new remote brain metastases, and 4.9% had leptomeningeal dissemination. Subsequent management included repeat SRS in 21.7%, surgical resection in 8.8% and WBRT in 7.6% of patients. At last follow-up, 32.1% of patients had improvement of their symptoms, whereas 38.5% remained stable. Adverse radiation effects occurred in 4.3% of treated metastases. On multivariate analyses, KPS ≥ 80% and non-urothelial histology predicted improved survival, while absence of corticosteroid intake predicted longer tumor control. CONCLUSION/CONCLUSIONS:Bladder cancer brain metastases can be safely managed with SRS.

Spetzler-Martin Grade IV arteriovenous malformations (AVMs) are challenging due to high risks associated with both treatment and natural progression. This study compares the outcomes of microsurgical resection and stereotactic radiosurgery (SRS) in high-grade AVMs, analyzing obliteration rates, complications, and functional outcomes. A retrospective cohort of 96 patients treated with either microsurgical resection (33 patients) or SRS (63 patients) was analyzed. Propensity-score matching was employed to account for baseline variables such as AVM size (cm), preoperative embolization and rupture status. Primary endpoints included AVM obliteration, complication rates, and modified Rankin Scale (mRS) scores. After matching, 31 patients per group were analyzed. Microsurgical resection achieved significantly higher obliteration rates (87.1%) compared to SRS (32.3%, p < 0.001). In the matched SRS cohort (n = 31), the actuarial obliteration rates were 11% (95% CI: 0-22%) at 1 year, 17% (95% CI: 0-31%) at 3 years, and 43% (95% CI: 13-63%) at 5 years post-treatment. Complication rates were similar (32.3% resection, 38.7% SRS, p = 0.6). Functional outcomes in terms of improvement in modified Rankin Scale (mRS) scores were observed in 50.0% of microsurgery patients and 41.4% of SRS patients. However, the absolute number of patients improving was similar (13 vs. 12), and the microsurgery group had more cases of worsening mRS scores compared to the SRS group (4 vs. 2). The difference was not statistically significant (p = 0.4). Microsurgical resection offers superior obliteration rates for high-grade AVMs with comparable complication risks to SRS. SRS remains a valuable alternative for select patients, particularly those ineligible for resection. Future research should focus on optimizing multimodal treatment approaches. Clinical trial number Not applicable.