Faculty Bibliography

BACKGROUND AND OBJECTIVES/OBJECTIVE:Stereotactic radiosurgery (SRS) represents an effective treatment for nonfunctioning pituitary adenomas (NFPAs). However, no data have yet been published regarding results of SRS on NFPAs after multiple previous resections. METHODS:Retrospective multicentric data of patients diagnosed with NFPA and who underwent multiple resections (≥2) before SRS were reviewed and analyzed. The treatment interval spanned the period of 1992 to 2022. Cox regression and Kaplan-Meier curves were used to assess predictive factors and the probability of tumor control and hypopituitarism. RESULTS:Among the 311 patients (median age: 50.2 [IQR: 18.0] years), 226 (72.7%) had undergone ≥2 previous resections. The median margin dose was 14 Gy (IQR: 4.0 Gy), and the median tumor volume 3.6 cm3 (IQR: 4.8). Overall, the probability of tumor control after SRS was 93.3% (CI 95%: 89.9-96.9) and 86.7% (CI 95%: 81.1-92.6) at 5 and 10 years, respectively. A margin dose >14 Gy was associated with a decreased risk of tumor progression (hazard ratio = 0.33, CI 95% = 0.15-0.75, P = .008). At a last clinical follow-up of 4.1 (IQR 6.1) years, 10.1% (30/296) developed at least 1 new hormone deficiency after SRS. The cumulative probability of new hormone deficiency was 6.1% (95% CI: 3.0-9.1), 10.3% (95% CI: 5.8-14.6), and 18.9% (95% CI: 11.5-25.8) at 3, 5, and 10 years after SRS, respectively. The average latency between SRS and development of new hormone deficiencies was 3.3 years (IQR 4.1). A maximum point dose to the pituitary stalk >10 Gy was associated with a new deficiency (hazard ratio = 4.06, CI 95% = 1.57-10.5, P-value = .004). CONCLUSION/CONCLUSIONS:For patients with NFPA with multiple previous resections, SRS offers effective local tumor control and a low risk of delayed hypopituitarism for managing these challenging adenomas. SRS should be strongly considered in patients with NFPA with 2 previous resections compared with considering a third resection.

BACKGROUND AND OBJECTIVES/OBJECTIVE:Pineocytomas are grade 1 tumors arising from the pineal parenchyma. Gross total resection can potentially cure these benign lesions but can be associated with morbidity. This study was designed to provide multi-institutional data to evaluate the results of stereotactic radiosurgery (SRS) for pineocytomas. METHODS:Centers participating in the International Radiosurgery Research Foundation were asked to review their database and provide data for patients who had SRS for histology confirmed grade 1 pineocytomas, for whom clinical and imaging follow-up of at least 6 months was available. RESULTS:In total, 38 patients underwent SRS as part of the management of a pineocytoma. The median age at SRS was 39 years (range 8-76). SRS was performed as primary approach in 68%, adjuvant after partial resection 19%, and at recurrence in 13% of patients. The median margin dose was 15 Gy (range 11-25 Gy). The median treatment volume was 3.35 cc (range 0.1-17.9 cc). Local tumor control was achieved in 92% of patients, with a mean actuarial progression-free survival of 21.6 years (median not reached). At last follow-up, 82% were still controlled, 8% had local recurrence, and 10% had cerebrospinal fluid dissemination. Tumor control was significantly better when SRS was used as primary care compared with the adjuvant or recurrent setting (P = .016). Five patients (13%) died during follow-up, all from tumor progression. The actuarial mean survival duration was 24.3 years, with a 5-year survival rate of 91%, and an estimated rate of 76% at 29 years. Larger tumor volume at SRS was found to be correlated to increased risk of death (P = .045). Transient symptomatic adverse radiation effects were observed in 4 patients (11%). CONCLUSION/CONCLUSIONS:SRS appears safe and effective for the management of pineocytomas. Long-term tumor control is achieved in most cases. SRS can be offered to selected patients as an alternative to surgical resection.

BACKGROUND AND OBJECTIVES/OBJECTIVE:Infratentorial arteriovenous malformations (AVMs) harbor different characteristics compared with supratentorial AVMs. This study aims to explore the unique characteristics of pediatric infratentorial AVMs and their response to single session stereotactic radiosurgery (SRS). METHODS:The International Radiosurgery Research Foundation database of pediatric patients with AVM (age <18 years) who underwent SRS was retrospectively reviewed. Baseline demographics, AVM characteristics, outcomes, and complications post-SRS were compared between infratentorial and supratentorial pediatric AVMs. Unfavorable outcome was defined as the absence of AVM obliteration, post-SRS hemorrhage, or permanent radiation-induced changes at last follow-up. RESULTS:A total of 535 pediatric AVMs managed with SRS with a median follow-up of 67 months (IQR 29.0-130.6) were included, with 69 being infratentorial and 466 supratentorial. The infratentorial group had a higher proportion of deep location (58.4% vs 30.3%, P = <.001), deep venous drainage (79.8% vs 61.8%, P = .004), and prior embolization (26.1% vs 15.7%, P = .032). There was a higher proportion of hemorrhagic presentation in the infratentorial group (79.7% vs 71.3%, P = .146). There was no statistically significant difference in the odds of an unfavorable outcome (odds ratio [OR] = 1.36 [0.82-2.28]), AVM obliteration (OR = 0.85 [0.5-1.43]), post-SRS hemorrhage (OR = 0.83 [0.31-2.18]), or radiologic radiation-induced changes (OR = 1.08 [0.63-1.84]) between both cohorts. No statistically significant difference on the rates of outcomes of interest and complications were found in the adjusted model. CONCLUSION/CONCLUSIONS:Despite baseline differences between infratentorial and supratentorial pediatric AVMs, SRS outcomes, including AVM obliteration and post-SRS hemorrhage rates, were comparable amongst both groups. SRS appears to have a similar risk profile and therapeutic benefit to infratentorial pediatric AVMs as it does for those with a supratentorial location.

Brainstem cerebral cavernous malformations (CCM) are clinically more aggressive compared to superficial CCMs. Due to their location, resection can be challenging, making stereotactic radiosurgery (SRS) an attractive alternative for symptomatic patient. Brainstem CCM patients (n = 170) were treated with Gamma Knife SRS at 11 radiosurgical centers. Hemorrhagic risk reduction, risk factors of post-SRS hemorrhage, and clinical outcomes were retrospectively analyzed. Most patients had a single (165/170 patients) brainstem CCMs treated; the majority of CCMs (165/181) presented with bleeding. Single-session SRS decreased the risk of repeat hemorrhage in patients with hemorrhagic brainstem CCM (HR: 0.17, p < 0.001) using recurrent multivariate analysis. The annual hemorrhage rate decreased from 14.8 per 100 CCM-years before SRS to 2.3 after treatment. Using univariate Cox-analysis, the probability of a new hemorrhages after SRS was reduced for patient older than 35 years (HR = 0.21, p = 0.002) and increased with a margin dose > 13 Gy (HR = 2.57, p = 0.044). Adverse radiation effect (ARE) occurred in 9 patients (5.3%) and was symptomatic in four (2.4%). At a median follow-up of 3.4 years (Inter-quartile range: 5.4), 13 patients (8.0%) had a worsened clinical status, with the treated CCM being the cause in 5.6% (10) of the patients. Single-session SRS decreased the risk of repeat hemorrhage in patients with hemorrhagic brainstem CCM and conveyed this benefit with a low risk of advrse radiation effects (ARE) and worsening clinical status.

BACKGROUND AND OBJECTIVES/OBJECTIVE:Trigeminal Neuralgia (TN) is a debilitating facial pain disorder, often necessitating surgical interventions when medication proves insufficient. Stereotactic Radiosurgery (SRS) is an established therapeutic option. Limited studies explored the feasibility of a third SRS procedure. Our study investigates the safety and efficacy of a third SRS procedure for recurrent TN. METHODS:We performed a retrospective analysis across multiple centers using databases collected prospectively. Pain status was evaluated utilizing the BNI Pain Intensity Scales. The Kaplan-Meier method was employed to estimate the time to recurrence, with group comparisons conducted using log-rank tests. Associations were explored using Chi-square and logistic regression models. RESULTS:Ten institutions contributed with a total of 35 patients. A third SRS revealed sustained effectiveness with a pain control rate of 82.7%. The median time to recurrence was 35.5 months. New sensory dysfunction following the third procedure occurred in 22% of patients who had preserved sensory function after the second procedure. When considering those who developed sensory dysfunction after the second procedure, 40% of the entire cohort was affected. There were no significant differences in pain recurrence intervals among the three procedures. A meta-analysis, combining data from previous studies, showed that 89.6% of patients achieved some degree of pain control after a third SRS, with 27.4% experiencing new sensory dysfunction and a median time to recurrence of 31.6 months. CONCLUSION/CONCLUSIONS:Our study, the largest on the topic, affirms the sustained effectiveness of a third SRS for TN, providing comparable pain relief to initial procedures. Notably, an extended pain-free interval after the third SRS session was observed. Facial sensory dysfunction emerged as the primary side effect. Larger studies are warranted to explore correlations with demographics and treatment parameters for a comprehensive understanding of repeat SRS in managing recurrent TN.

BACKGROUND AND OBJECTIVES/OBJECTIVE:Studies comparing neurological and radiographic outcomes of repeat to initial stereotactic radiosurgery (SRS) intracranial arteriovenous malformations are scarce. Our aim was to perform a retrospective matched comparison of patients initially treated with SRS with those undergoing a second radiosurgical procedure. METHODS:We collected data from arteriovenous malformations managed in 21 centers that underwent initial and repeated radiosurgery from 1987 to 2022. Based on arteriovenous malformations volume, margin dose, deep venous drainage, deep, and critical location, we matched 1:1 patients who underwent an initial SRS for treatment-naive arteriovenous malformations and a group with repeated SRS treatment. RESULTS:After the selection process, our sample consisted of 328 patients in each group. Obliteration in the initial SRs group was 35.8% at 3 and 56.7% at 5 years post-SRS, while the repeat SRS group showed obliteration rates of 33.9% at 3 years and 58.6% at 5 years, without statistically significant differences (P = .75 and P = .88, respectively). There were no statistically significant differences between the 2 groups for obliteration rates (hazard ratio = 0.93; 95% CI, 0.77-1.13; P = .5), overall radiation-induced changes (RIC) (OR = 1.1; 95% CI, 0.75-1.6; P = .6), symptomatic RIC (OR = 0.78; 95% CI, 0.4-1.5; P = .4), and post-SRS hemorrhage (OR = 0.68; 95% CI; P = .3). CONCLUSION/CONCLUSIONS:In matched cohort analysis, a second SRS provides comparable outcomes in obliteration and RIC compared with the initial SRS. Dose reduction on repeat SRS may not be warranted.

PURPOSE/OBJECTIVE:The present study assesses the safety and efficacy of stereotactic radiosurgery (SRS) versus observation for Koos grade 1 and 2 vestibular schwannoma (VS), benign tumors affecting hearing and neurological function. METHODS AND MATERIALS/METHODS:This multicenter study analyzed data from Koos grade 1 and 2 VS patients managed with SRS (SRS group) or observation (observation group). Propensity score matching balanced patient demographics, tumor volume, and audiometry. Outcomes measured were tumor control, serviceable hearing preservation, and neurological outcomes. RESULTS:In 125 matched patients in each group with a 36-month median follow-up (P = .49), SRS yielded superior 5- and 10-year tumor control rates (99% CI, 97.1%-100%, and 91.9% CI, 79.4%-100%) versus observation (45.8% CI, 36.8%-57.2%, and 22% CI, 13.2%-36.7%; P < .001). Serviceable hearing preservation rates at 5 and 9 years were comparable (SRS 60.4% CI, 49.9%-73%, vs observation 51.4% CI, 41.3%-63.9%, and SRS 27% CI, 14.5%-50.5%, vs observation 30% CI, 17.2%-52.2%; P = .53). SRS were associated with lower odds of tinnitus (OR = 0.39, P = .01), vestibular dysfunction (OR = 0.11, P = .004), and any cranial nerve palsy (OR = 0.36, P = .003), with no change in cranial nerves 5 or 7 (P > .05). Composite endpoints of tumor progression and/or any of the previous outcomes showed significant lower odds associated with SRS compared with observation alone (P < .001). CONCLUSIONS:SRS management in matched cohorts of Koos grade 1 and 2 VS patients demonstrated superior tumor control, comparable hearing preservation rates, and significantly lower odds of experiencing neurological deficits. These findings delineate the safety and efficacy of SRS in the management of this patient population.

The detection and tracking of metastatic cancer over the lifetime of a patient remains a major challenge in clinical trials and real-world care. Advances in deep learning combined with massive datasets may enable the development of tools that can address this challenge. We present NYUMets-Brain, the world's largest, longitudinal, real-world dataset of cancer consisting of the imaging, clinical follow-up, and medical management of 1,429 patients. Using this dataset we developed Segmentation-Through-Time, a deep neural network which explicitly utilizes the longitudinal structure of the data and obtained state-of-the-art results at small (<10 mm³) metastases detection and segmentation. We also demonstrate that the monthly rate of change of brain metastases over time are strongly predictive of overall survival (HR 1.27, 95%CI 1.18-1.38). We are releasing the dataset, codebase, and model weights for other cancer researchers to build upon these results and to serve as a public benchmark.

BACKGROUND AND OBJECTIVES/OBJECTIVE:Pediatric spine surgery has evolved considerably over the past century. No previous study conducted a bibliometric analysis of the corpus of pediatric spine surgery. We used big data and advanced bibliometric analyses to evaluate trends in the progression of pediatric spine surgery as a distinct field since the beginning of the 20th century. METHODS:A Web of Science query was designed to capture the representative corpus of pediatric spine literature. Statistical and bibliometric analyses were performed using various Python packages and the Bibliometrix R package. RESULTS:The collection, published from 1902 to 2023, comprised a total of 11 861 articles from 61 journals and 32 715 unique authors. The overall growth rate annually for publications was 5.08%. An upsurge in publications was seen in the 1980s, after the advent of specialty and subspecialty journals. Illustratively, over 90% of all articles pertaining to pediatric spine surgery were published in the past 3 decades. International and domestic collaboration also increased exponentially over this time period. Reference publication year spectroscopy allowed us to identify 75 articles that comprise the historical roots of modern pediatric spine surgery. There was a recent lexical evolution of topics and terms toward alignment, outcomes, and patient-centric terms. Coauthorship among under-represented groups increased since 1990, but remains low, with disparities persisting across journals. CONCLUSION/CONCLUSIONS:This comprehensive bibliometric analysis on the corpus of pediatric spine surgery offers insight into the evolving landscape of research, authorship, and publication trends over the past century. Advancements in the understanding of the natural history and technology have led the field to become increasingly outcomes focused, all of which have been fueled by pioneering authors. While diversity among authors improves, under-representation of various groups continues to persist, indicating a critical role for further outreach and promotion.

OBJECTIVE:Concussions can occur at any level of ice hockey. Incidence estimates of concussions in ice hockey vary, and optimal prevention strategies and return-to-play (RTP) considerations have remained in evolution. The authors performed a mixed-methods study with the aim of elucidating the landscape of concussion in ice hockey and catalyzing initiatives to standardize preventative mechanisms and RTP considerations. METHODS:The authors performed a five-part mixed-methods study that includes: 1) an analysis of the impact of concussions on games missed and income for National Hockey League (NHL) players using a publicly available database, 2) a systematic review of the incidence of concussion in ice hockey, 3) a systematic review of preventative strategies, 4) a systematic review of RTP, and 5) a policy review of documents from major governing bodies related to concussions in sports with a focus on ice hockey. The PubMed, Embase, and Scopus databases were used for the systematic reviews and focused on any level of hockey. RESULTS:In the NHL, 689 players had 1054 concussions from the 2000-2001 to 2022-2023 seasons. A concussion led to a mean of 13.77 ± 19.23 (range 1-82) games missed during the same season. After cap hit per game data became available in 2008-2009, players missed 10,024 games due to 668 concussions (mean 15.13 ± 3.81 per concussion, range 8.81-22.60 per concussion), with a cap hit per game missed of $35,880.85 ± $25,010.48 (range $5792.68-$134,146.30). The total cap hit of all missed games was $385,960,790.00, equating to $577,635.91 per concussion and $25,724,052.70 per NHL season. On systematic review, the incidence of concussions was 0.54-1.18 per 1000 athlete-exposures. Prevention mechanisms involved education, behavioral and cognitive interventions, protective equipment, biomechanical studies, and policy/rule changes. Rules prohibiting body checking in youth players were most effective. Determination of RTP was variable. Concussion protocols from both North American governing bodies and two leagues mandated that a player suspected of having a concussion be removed from play and undergo a six-step RTP strategy. The 6th International Conference on Concussion in Sport recommended the use of mouthguards for children and adolescents and disallowing body checking for all children and most levels of adolescents. CONCLUSIONS:Concussions in ice hockey lead to substantial missed time from play. The authors strongly encourage all hockey leagues to adopt and adhere to age-appropriate rules to limit hits to the head, increase compliance in wearing protective equipment, and utilize high-quality concussion protocols.