Faculty Bibliography

BACKGROUND AND OBJECTIVES/OBJECTIVE:Hypofractionated Gamma Knife radiosurgery (hfGKRS) is increasingly considered for treating large or near-critical structure meningiomas because of potential safety advantages. However, data on optimal fractionation and long-term outcomes remain limited. This study evaluated the longer-term tumor control and toxicity after hfGKRS for intracranial meningiomas at 2 large centers, supplemented by a systematic review and meta-analysis of existing literature. METHODS:The analysis included 34 patients (site 1 = 25, site 2 = 9, median age 62.6 years) with 40 tumors (median volume 11.2 cm3). 62% was low-grade (World Health Organization grade 0-1) and 38% was high-grade (World Health Organization grade 2-3). The most common fractionation schemes were 20 Gy in 5 fractions for low-grade and 21 Gy in 3 fractions for high-grade tumors. The mean follow-up was 28.8 months. RESULTS:Only 6 of 34 patients did not have any previous treatment including surgery and/or radiotherapy. 82% of patient patients had neurological deficits before stereotactic radiosurgery. The estimated rate of 5-year tumor progression for low-grade and high-grade tumors was 7.7% (95% CI 0.41%-30%) and 36% (95% CI 12%-62%). Symptoms improved in 12 patients (35%) and worsened in 6 patients (16%), with 1 case attributed to tumor progression and no significant visual deterioration in 16 tumors within 3 mm of the optic apparatus. There was no statistically significant association between fractionation (3 vs 5) scheme and tumor control (P = .07) or survival (P = .12). Karnofsky Performance Status performance was a significant predictor of death (HR 0.89, P = .012) and tumor progression (HR 0.93, P = .048). The combined meta-analysis revealed a 5-year tumor control rate of 91.6% for low-grade and 37.9% for high-grade meningiomas. CONCLUSION/CONCLUSIONS:hfGKRS demonstrates durable control and acceptable safety for low-grade intracranial meningiomas. High-grade tumors showed less favorable outcomes comparable with single-session Gamma Knife radiosurgery historical data. Further prospective data are needed to confirm these findings and optimize fractionation strategies.

OBJECTIVES/OBJECTIVE:Traditionally, disorders of the vocal fold (VF) mucosa and underlying musculature have been regarded as mutually exclusive entities. However, emerging evidence from other organ systems suggests mucosal and muscle compartments engage in reciprocal interactions with functional consequences. We hypothesized that similar crosstalk exists in the VF, whereby fibrotic mucosa influences adjacent muscle. To model this process, we stimulated human VF fibroblasts (HVOX) with TGF-β1, a central mediator of fibrosis, and examined the effects on rat VF myoblasts (rVF-Mbs), as well as reciprocal influences of rVF-Mbs on fibroblasts. METHODS:HVOX fibroblasts were stimulated with 10 ng/mL TGF-β1, and the effects on rVF-Mbs were assessed using conditioned media and co-culture. Myotube formation was evaluated by immunofluorescence, and nuclear localization of Smad2/3 was examined in conditioned media experiments. qRT-PCR quantified transcripts related to myogenic differentiation and Smad2/3 signaling. ALK4/5 inhibition was performed in co-culture to test TGF-β/Smad2/3-signaling pathway involvement. Reciprocal effects were examined by changes in fibrogenic gene expression in HVOX fibroblasts. RESULTS:Both conditioned media and co-culture suppressed myogenic differentiation in rVF-Mbs; increased inhibition was observed in co-culture, as indicated by reduced myotube formation, decreased Myh2 expression, and activation of Smad2/3 signaling. ALK4/5 inhibition abrogated these effects. Differentiating rVF-Mbs attenuated the fibrogenic phenotype of HVOX fibroblasts. CONCLUSIONS:Fibrotic VF mucosal cells can impair myogenic differentiation through TGF-β/Smad2/3-mediated fibroblast-myoblast crosstalk, and myogenic cells may exert reciprocal anti-fibrotic effects. These findings suggest mucosa-muscle interactions may contribute to VF pathology and highlight Smad2/3 as a potential therapeutic target. LEVEL OF EVIDENCE/METHODS:NA STUDY DESIGN: In vitro.

OBJECTIVE:To describe intraoperative fluoroscopic and transimpedance matrix (TIM) findings during cochlear implantation in a patient with bilateral cochlear malformations, highlighting the dynamic relationship between electrode position and evolving TIM heatmap patterns. STUDY DESIGN/METHODS:Case report. METHODS:Retrospective review of patient medical and radiographic records, intraoperative fluoroscopy, and TIM data. RESULTS:Initial insertion produced a previously characterized TIM skip heat pattern seen in patients with incomplete partition type II and deficient interscalar septal width. This prompted partial electrode withdrawal under fluoroscopy, which subsequently resulted in a TIM central heat pattern, representing a symmetric voltage concentration around the mid-array region. Advancing the array slightly resulted in a skip heat pattern with a more defined current delineation and a more favorable x-ray profile. Interestingly, SmartNav analysis interpreted the TIM data as a tip fold over, despite good positioning. CONCLUSION/CONCLUSIONS:This case visually demonstrates which small positional changes of electrodes within malformed cochleae can transform TIM morphology, helping to elucidate why certain patterns occur, and the next steps to study clinical relevance.

BACKGROUND AND OBJECTIVES/OBJECTIVE:General purpose vision-language models (VLMs) demonstrate impressive capabilities, but their opaque training on uncurated internet data poses critical limitations for high-stakes decision making, such as in neurosurgery. We present CNS-Obsidian, a neurosurgical VLM trained on peer-reviewed neurosurgical literature, and demonstrate its clinical utility compared with GPT-4o in a real-world setting. METHODS:We compiled 23 984 articles from Neurosurgery Publications journals, yielding 78 853 figures and captions. Using GPT-4o and Claude Sonnet-3.5, we converted these image-text pairs into 263 064 training samples across 3 formats: instruction fine-tuning, multiple-choice questions, and differential diagnosis. We trained CNS-Obsidian, a fine-tune of the 34-billion parameter Large Language and Visual Assistant-Next model. In a blinded, randomized deployment trial at NYU Langone Health (August 30-November 30, 2024), neurosurgeons were assigned to use either CNS-Obsidian or a Health Insurance Portability and Accountability Act-compliant GPT-4o end point as a diagnostic copilot after patient consultations. Primary outcomes were diagnostic helpfulness and accuracy, assessed through user ratings and presence of the correct diagnosis within the VLM-provided differential, respectively. RESULTS:CNS-Obsidian matched GPT-4o on synthetic questions (76.13% vs 77.54%, P = .235), but only achieved 46.81% accuracy on human-generated questions vs GPT-4o's 65.70% (P < 10-15). In the randomized trial, 70 consultations were evaluated (32 CNS-Obsidian, 38 GPT-4o) from 959 total consults (7.3% utilization). CNS-Obsidian received positive ratings in 40.62% of cases vs 57.89% for GPT-4o (P = .230). Both models included correct diagnosis in approximately 60% of cases (59.38% vs 65.79%, P = .626). CONCLUSION/CONCLUSIONS:Domain-specific VLMs trained on curated scientific literature can approach frontier model performance in specialized medical domains despite being orders of magnitude smaller and less expensive to train. This establishes a transparent framework for scientific communities to build specialized artificial intelligence models. However, low clinical utilization suggests chatbot interfaces may not align with specialist workflows, indicating need for alternative artificial intelligence integration strategies.

Protease-activated receptor 2 (PAR₂) mediates oral cancer pain. Patients with metastatic (N + ) cancers report greater pain. PAR₂ is activated by N-terminal proteolytic cleavage. Here we show that proteases encoded by genes overexpressed in N+ cancers from patients with pain (matrix metallopeptidase 1, MMP1 and serine protease 23, PRSS23) elicit protease-specific receptor redistribution (trafficking) and signaling that differs from that promoted by proteases encoded by genes not differentially expressed (transmembrane serine protease matriptase, ST14 and cathepsin S, CTSS). Mixtures of the proteases prepared to model the oral cancer microenvironment revealed that ST14-mediated PAR₂ activation predominated at low protease concentrations. At high concentrations, MMP1 and PRSS23 prevailed over the greater potency of ST14. We propose that PAR₂ activation in oral N+ cancers from patients with pain is driven by high levels of MMP1 and PRSS23. Our study informs design of signaling and location-specific antagonists to provide more efficacious analgesia.

Vocalizations are ancient behaviours that require the complex coordination of breath and display. Understanding how laryngeal anatomy shapes vocalization provides insights into this diversity, its mechanisms and their evolution. Rodents are ideal for exploring this variation because of their diverse mechanisms and vocal structures. Here, we describe the laryngeal morphology and sound production mechanisms underlying the vocalizations of Alston's singing mouse (Scotinomys teguina) and compare these results to those of other vocalizing mammals. We reconstructed the three-dimensional laryngeal morphology with micro-computed tomography, recorded laryngeal sound production using high-speed video and investigated frequency control using surgical ablations. We found that singing mice use a whistle mechanism that uniquely relies on the inflation of an enlarged air sac called the ventral pouch. Song frequency can be controlled by pouch volume, airflow and cricothyroid muscle action. Singing mouse laryngeal morphology and vocal mechanism are distinct from those of other Neotomids; singing mice appear to use inflation-mediated whistles for both distant and close exchanges. Inflatable air sacs have evolved repeatedly for sound modulation and filtering. Our results indicate a novel role for these structures in being required to generate sound. Together, our results expand on an emerging story of how biomechanic and morphological variation contributes to vocal diversity.

The relation between the vocal capacities of animals and those of humans is a long-standing topic of interest for scientists, philosophers, and lay people alike. While similar neural and physiological substrates underlie the production of vocal signals in humans and animals, the most celebrated and prototypical aspects of language are cognitive phenomena that go far beyond speech sensorimotor processes. These include a subset of features that have begun to be systematically investigated in nonhuman animals, namely: (i) the presence of statistical laws, (ii) hierarchical syntactic rules, and (iii) the capacity for meaning and reference. Here we review recent progress describing and quantifying language-like structure in animal vocalizations. We highlight agreement and disagreement about the similarities that may exist between human language and animal vocal repertoires, with an eye toward what these phenomena may reveal about the evolution of language and its neural control.

BACKGROUND AND OBJECTIVES/OBJECTIVE:Surgery in NF2-related schwannomatosis (NF2-SWN) vestibular schwannoma (VS) carries a higher risk of facial nerve damage, hearing loss, and partial resection, than in sporadic cases. Radiosurgery is also associated with higher failure compared with sporadic schwannomas. Nowadays, bevacizumab (BEV) is frequently considered in the NF2-SWN population. However, some patients experience progression despite treatment. Among other surgical risks, in BEV-treated patients, hemorrhage and impaired healing are specific considerations. These concerns have led manufacturers to recommend stopping BEV 6 to 8 weeks preoperatively. The aim of our multicentric study was to assess the perioperative bleeding risk and postoperative outcomes in NF2-SWN patients undergoing VS surgery after preoperative BEV treatment. METHODS:Our retrospective analysis included medical and surgical records along with imaging reviews from 4 high-volume tertiary academic referral centers for NF2-SWN and VS. RESULTS:A total of 21 patients met the inclusion criteria. VS had a mean volume of 13.2 ±7.6 cm3 corresponding to 1 KOOS III and 20 KOOS IV. BEV was stopped at a mean of 5.8 ± 4.0 months before surgery with a total mean treatment duration of 33.7 ± 20.7 months and a monthly dose of 10.2 ± 4.1 mg/kg. Intraoperatively, the tumor was assessed to be bloody by the operating surgeons in 7 patients. Late BEV discontinuation and high cumulative dose independently predicted perioperative bleeding and longer surgery duration. No other complication such as wound dehiscence was reported. CONCLUSION/CONCLUSIONS:Our findings suggest that a higher cumulative BEV dose (∼600 mg/kg) and a longer interval between BEV discontinuation and surgery (∼8 months) are associated with a modest but statistically significant increase in intraoperative bleeding risk. Based on these observations, a BEV-free window between 6 weeks and 6 months (depending on the clinical scenario) before tumor resection seems optimal, particularly for patients with high cumulative exposure.

The Society of Thoracic Surgeons (STS) 2026 Expert Consensus Pathway on Robotic Cardiac Training outlines principles for the safe initial introduction and subsequent expansion of robotic cardiac programs. The 25-year history of robotic cardiac surgery has established safety and efficacy while providing multiple innovations. There is currently a unique opportunity to coalesce best practices and evidence to inform a recent global surge in interest in incorporating robotic techniques into standard cardiac surgical practice. This consensus is a collaborative effort between the STS Workforce on Evidence Based Surgery, the STS Robotic Cardiac Surgery Taskforce, and multinational leaders in robotic cardiac surgery that aims to standardize initial core principles of preparatory elements, followed by 4 phases of robotic cardiac training to proceed from program commencement to mastery.

Electrical and structural remodeling of the heart can contribute to the development of cardiac arrhythmias. Ex vivo optical mapping has been used to visualize cardiac electrophysiological properties, activation and phase maps to further elucidate the mechanisms of atrial fibrillation and ventricular fibrillation initiation and persistence. Here we show an epicardial three-dimensional panoramic optical mapping tool integrated with micro-computed tomography automatically segmented with a deep learning model relying on a convolutional neural network to provide structural and electrical activation information in a single three-dimensional volume of a mouse heart. This technique allows for the acquisition and analysis of electrical activity of the entire epicardial surface with submillimeter spatial resolution and a temporal resolution of 1 ms. We establish the use of this method in transgenic mouse hearts with spontaneous atrial fibrillation and ventricular fibrillation, and mouse surgical models of myocardial infarction and left ventricular hypertrophy.