Comparative analysis of the spatial distribution of brain metastases across several primary cancers using machine learning and deep learning models.

OBJECTIVE: Brain metastases (BM) are associated with poor prognosis and increased mortality rates, making them a significant clinical challenge. Studying BMs can aid in improving early detection and monitoring. Systematic comparisons of anatomical distributions of BM from different primary cancers, however, remain largely unavailable. METHODS: To test the hypothesis that anatomical BM distributions differ based on primary cancer type, we analyze the spatial coordinates of BMs for five different primary cancer types along principal component (PC) axes. The dataset includes 3949 intracranial metastases, labeled by primary cancer types and with six features. We employ PC coordinates to highlight the distinctions between various cancer types. We utilized different Machine Learning (ML) algorithms (RF, SVM, TabNet DL) models to establish the relationship between primary cancer diagnosis, spatial coordinates of BMs, age, and target volume. RESULTS: Our findings revealed that PC1 aligns most with the Y axis, followed by the Z axis, and has minimal correlation with the X axis. Based on PC1 versus PC2 plots, we identified notable differences in anatomical spreading patterns between Breast and Lung cancer, as well as Breast and Renal cancer. In contrast, Renal and Lung cancer, as well as Lung and Melanoma, showed similar patterns. Our ML and DL results demonstrated high accuracy in distinguishing BM distribution for different primary cancers, with the SVM algorithm achieving 97% accuracy using a polynomial kernel and TabNet achieving 96%. The RF algorithm ranked PC1 as the most important discriminating feature. CONCLUSIONS: In summary, our results support accurate multiclass ML classification regarding brain metastases distribution.

Vestibular Schwannoma International Study of Active Surveillance Versus Stereotactic Radiosurgery: the VISAS Study.

BACKGROUND: The present study assesses the safety and efficacy of stereotactic radiosurgery (SRS) versus observation for Koos grade I and II vestibular schwannoma (VS), benign tumors affecting hearing and neurological function. METHODS: This multicenter study analyzed data from Koos grade I and II 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 (SHP), and neurological outcomes. RESULTS: In 125 matched patients in each group with a 36-month median follow-up (p=0.49), SRS yielded superior 5- and 10-year tumor control rates (99%, CI: 97.1%-100%, and 91.9%, CI: 79.4%-100%) vs. observation (45.8%, CI: 36.8%-57.2%, and 22%, CI: 13.2%-36.7%; p<0.001). SHP 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=0.53). SRS were associated with lower odds of tinnitus (OR=0.39, p=0.01), vestibular dysfunction (OR=0.11, p=0.004), and any cranial nerve palsy (OR=0.36, p=0.003), with no change in cranial nerves V or VII (p>0.05). Composite endpoints of tumor progression and/or any of the previous outcomes showed significant lower odds associated with SRS compared to observation alone (p < 0.001). CONCLUSION: SRS management in matched cohorts of Koos grade I and II 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 in the management of this patient population.

Comparison of the effects of opioid-free anesthesia (OFA) and opioid-based anesthesia (OBA) on postoperative analgesia and intraoperative hemodynamics in patients undergoing spine surgery: A prospective randomized double-blind controlled trial.

Background: Opioids form the basis of perioperative pain management but are associated with multiple side effects. In opioid-free anesthesia (OFA), several non-opioid drugs or neuraxial/regional blocks are used as substitutes for opioids. Ketamine, a N-methyl-d-aspartate antagonist, provides intense analgesia. However, there is a shortage of literature on the effects of ketamine-based OFA on hemodynamics (HD) and postoperative analgesia in patients undergoing thoracolumbar spine surgery. Materials and Methods: This prospective randomized controlled trial included 60 adult patients. The patients in Group OFA (n = 30) received OFA with ketamine and ketofol (1:5) infusion, and those in Group OBA (n = 30) received opioid-based anesthesia (OBA) with fentanyl and propofol infusion. The postoperative pain-free period, pain scores, rescue analgesia, intraoperative HDs, and postoperative complications were assessed. Results: The mean pain-free period in Group OFA (9.86 ± 1.43 hr) was significantly higher than that in Group OBA (6.93 ± 1.93 hr) (P = 0.002). During the postoperative 48 hours, the total requirement of fentanyl was considerably lower in Group OFA (P < 0.05). There was a significantly higher incidence of hypertension in Group OFA (46%) and hypotension (43%) in Group OBA (43%), respectively. Postoperative nausea vomiting (PONV) was more common in Group OBA at the 2nd and 6th hr (P = 0.046 and P = 0.038). Conclusion: OFA with ketamine and ketofol provided adequate postoperative analgesia with a lower incidence of PONV after spine surgery. However, hypertension in the ketamine group and hypotension in the propofol group required fine titration of the infusion rate of drugs during the intraoperative period.

Long-term radiographic and endocrinological outcomes of stereotactic radiosurgery for recurrent or residual nonfunctioning pituitary adenomas.

OBJECTIVE: Stereotactic radiosurgery (SRS) is used for the treatment of residual/recurrent nonfunctional pituitary adenoma (NFPA). The aim of this study was to evaluate the factors related to long-term tumor control and delayed endocrinopathies following SRS. METHODS: This retrospective, multicenter study included patients with recurrent/residual NFPA treated with single-fraction SRS; they were then divided into two arms. The first arm included patients with at least 5 years of radiographic follow-up and all patients with local tumor progression. The second arm included patients with at least 5 years of endocrinological follow-up and all patients who developed endocrinopathy. Study endpoints were tumor control and new or worsening hypopituitarism after SRS and were analyzed using Cox regression and Kaplan-Meier methodology. RESULTS: There were 360 patients in the tumor control arm (median age 52.7 [IQR 42.9-61] years, 193 [53.6%] males) and 351 patients in the hypopituitarism arm (median age 52.5 [IQR 43-61] years, 186 [53.0%] males). The median follow-up in the tumor control evaluation group was 7.95 (IQR 5.7-10.5) years. Tumor control rates at 5, 8, 10, and 15 years were 93% (95% CI 90%-95%), 87% (95% CI 83%-91%), 86% (95% CI 82%-90%), and 69% (95% CI 59%-81%), respectively. The median follow-up in the endocrinopathy evaluation group was 8 (IQR 5.9-10.7) years. Pituitary function preservation rates at 5, 8, 10, and 15 years were 83% (95% CI 80%-87%), 81% (95% CI 77%-85%), 78% (95% CI 74%-83%), and 71% (95% CI 63%-79%), respectively. A margin dose > 15 Gy (HR 0.8, 95% CI 0.7-0.9; p < 0.001) and a delay from last resection to SRS > 1 year (HR 0.9, 95% CI 0.7-0.9; p = 0.04) were significant factors related to tumor control in multivariable analysis. A maximum dose to the pituitary stalk ≤ 10 Gy (HR 1.1, 95% CI 1.09-1.2; p < 0.001) was associated with pituitary function preservation. New visual deficits after SRS occurred in 7 (1.94%) patients in the tumor control group and 8 (2.3%) patients in the endocrinopathy group. Other new cranial nerve deficits post-SRS occurred in 4 of 160 patients with data in the tumor control group and 3 of 140 patients with data in the endocrinopathy group. CONCLUSIONS: SRS affords favorable and durable tumor control for the vast majority of NFPAs. Post-SRS hypopituitarism occurs in a minority of patients, but this risk increases with time and warrants long-term follow-up.

Sexual Dysfunction after Clipping of Ruptured Intracranial Aneurysms.

BACKGROUND: Sexual dysfunction significantly affects interpersonal relationships and overall quality of life. It remains a matter of concern for risk assessment and counseling in patients with ruptured intracranial aneurysms. OBJECTIVE: To assess the sexual dysfunctions in patients undergoing clipping for ruptured intracranial aneurysms and comparative evaluation among different anterior circulation aneurysms. METHOD: We prospectively included 40 male patients of ruptured intracranial aneurysms of anterior circulation (age range: 20-60 years; sexually active preoperatively), managed with craniotomy and clipping. We evaluated the sexual outcome in patients with excellent Glasgow outcome score (GOS) five at a minimum one year of follow-up. Patients with GOS-5 status at follow-up were broadly classified into two groups: Anterior communicating artery aneurysm (Acom), and non-Acom) aneurysms. We valued sexual outcome with Subjective Sexual Arousal Scale for Men at follow-up, and compared in the two groups. RESULTS: Mean age of patients was 44.78 ± 9.51 years. Besides 20 Acom aneurysms, other groups included 11 middle cerebral artery aneurysms, five internal carotid artery aneurysms, three posterior communicating artery aneurysms, and one distal anterior cerebral artery aneurysm. The mean follow-up was 24.45 ± 13.58 months. Patients with non-Acom aneurysms had an overall better outcome in the sexual performance domain "P = 0.015," mental satisfaction domain "P = 0.009," and sexual assertiveness domain "P = 0.007." However, there was no statistical difference in partner communication domain "P = 0.593," and partner relationship domain "P = 0.378." Overall, the sexual outcome was inferior in patients treated for Acom aneurysms compared to other anterior circulation aneurysms. CONCLUSIONS: In cases of aneurysmal subarachnoid hemorrhage, sexual dysfunctions are common even after good clinical outcomes. The study revealed prominent differences in outcomes on the sexual quality of life in patients harboring Acom aneurysms as compared to anterior circulation aneurysms located off-midline.

The relevance of biologically effective dose for pain relief and sensory dysfunction after Gamma Knife radiosurgery for trigeminal neuralgia: an 871-patient multicenter study.

OBJECTIVE: Recent studies have suggested that biologically effective dose (BED) is an important correlate of pain relief and sensory dysfunction after Gamma Knife radiosurgery (GKRS) for trigeminal neuralgia (TN). The goal of this study was to determine if BED is superior to prescription dose in predicting outcomes in TN patients undergoing GKRS as a first procedure. METHODS: This was a retrospective study of 871 patients with type 1 TN from 13 GKRS centers. Patient demographics, pain characteristics, treatment parameters, and outcomes were reviewed. BED was compared with prescription dose and other dosimetric factors for their predictive value. RESULTS: The median age of the patients was 68 years, and 60% were female. Nearly 70% of patients experienced pain in the V2 and/or V3 dermatomes, predominantly on the right side (60%). Most patients had modified BNI Pain Intensity Scale grade IV or V pain (89.2%) and were taking 1 or 2 pain medications (74.1%). The median prescription dose was 80 Gy (range 62.5-95 Gy). The proximal trigeminal nerve was targeted in 77.9% of cases, and the median follow-up was 21 months (range 6-156 months). Initial pain relief (modified BNI Pain Intensity Scale grades I-IIIa) was noted in 81.8% of evaluable patients at a median of 30 days. Of 709 patients who achieved initial pain relief, 42.3% experienced at least one pain recurrence after GKRS at a median of 44 months, with 49.0% of these patients undergoing a second procedure. New-onset facial numbness occurred in 25.3% of patients after a median of 8 months. Age ≥ 63 years was associated with a higher probability of both initial pain relief and maintaining pain relief. A distal target location was associated with a higher probability of initial and long-term pain relief, but also a higher incidence of sensory dysfunction. BED ≥ 2100 Gy2.47 was predictive of pain relief at 30 days and 1 year for the distal target, whereas physical dose ≥ 85 Gy was significant for the proximal target, but the restricted range of BED values in this subgroup could be a confounding factor. A maximum brainstem point dose ≥ 29.5 Gy was associated with a higher probability of bothersome facial numbness. CONCLUSIONS: BED and physical dose were both predictive of pain relief and could be used as treatment planning goals for distal and proximal targets, respectively, while considering maximum brainstem point dose < 29.5 Gy as a potential constraint for bothersome numbness.

Pediatric cerebral cavernous malformations and stereotactic radiosurgery: an analysis of 50 cases from a multicentric study.

OBJECTIVE: Cerebral cavernous malformations (CCMs) are the second most common vascular anomaly affecting the CNS in children. Although stereotactic radiosurgery (SRS) has been proposed as an alternative to microsurgery in the management of selected cases in adults, there is a paucity of studies focusing on pediatric patients. The aim of this study was to present the outcomes and associated risks of SRS in this subgroup of patients. METHODS: This retrospective multicenter study included pediatric patients treated with single-session SRS for CCMs. The annual hemorrhage rate (AHR) was calculated before and after SRS in hemorrhagic lesions. The Engel classification was used to describe post-SRS epileptic control. Adverse radiation effects (AREs) and the occurrence of new neurological deficits were recorded. RESULTS: The study included 50 patients (median age 15.1 [IQR 5.6] years) harboring 62 CCMs. Forty-two (84%) and 22 (44%) patients had a history of hemorrhage or epilepsy prior to SRS, respectively. The AHR from diagnosis to SRS excluding the first hemorrhage was 7.19 per 100 CCM-years, dropping to 3.15 per 100 CCM-years after treatment. The cumulative risk of first hemorrhage after SRS was 7.4% (95% CI 0%-14.3%) at 5 years and 23.6% (95% CI 0%-42.2%) at 10 years. Eight hemorrhagic events involving 6 CCMs in 6 patients were recorded in the post-SRS follow-up period; 4 patients presented with transient symptoms and 4 with permanent symptoms. Of the 22 patients with pre-SRS seizures, 11 were seizure free at the last follow-up (Engel class I), 6 experienced improvement (Engel class II or III), 5 had no improvement (Engel class IVA or IVB), and 1 experienced worsening (Engel class IVC). Radiographic AREs were documented in 14.5% (9/62) of CCMs, with 4 being symptomatic. CONCLUSIONS: Single-session SRS reduces the CCM hemorrhage rate in the pediatric population and provides adequate seizure control.

Repeat stereotactic radiosurgery for persistent cerebral arteriovenous malformations in pediatric patients.

OBJECTIVE: The purpose of this study was to describe the long-term outcomes and associated risks related to repeat stereotactic radiosurgery (SRS) for persistent arteriovenous malformations (AVMs) in pediatric patients. METHODS: Under the auspices of the International Radiosurgery Research Foundation, this retrospective multicenter study analyzed pediatric patients who underwent repeat, single-session SRS between 1987 and 2022. The primary outcome variable was a favorable outcome, defined as nidus obliteration without hemorrhage or neurological deterioration. Secondary outcomes included rates and probabilities of hemorrhage, radiation-induced changes (RICs), and cyst or tumor formation. RESULTS: The cohort included 83 pediatric patients. The median patient age was 11 years at initial SRS and 15 years at repeat SRS. Fifty-seven children (68.7%) were managed exclusively using SRS, and 42 (50.6%) experienced hemorrhage prior to SRS. Median AVM diameter and volume were substantially different between the first (25 mm and 4.5 cm3, respectively) and second (16.5 mm and 1.6 cm3, respectively) SRS, while prescription dose and isodose line remained similar. At the 5-year follow-up evaluation from the second SRS, nidus obliteration was achieved in 42 patients (50.6%), with favorable outcome in 37 (44.6%). The median time to nidus obliteration and hemorrhage was 35.5 and 38.5 months, respectively. The yearly cumulative probability of favorable outcome increased from 2.5% (95% CI 0.5%-7.8%) at 1 year to 44% (95% CI 32%-55%) at 5 years. The probability of achieving obliteration followed a similar pattern and reached 51% (95% CI 38%-62%) at 5 years. The 5-year risk of hemorrhage during the latency period after the second SRS reached 8% (95% CI 3.2%-16%). Radiographically, 25 children (30.1%) had RICs, but only 5 (6%) were symptomatic. Delayed cyst formation occurred in 7.2% of patients, with a median onset of 47 months. No radiation-induced neoplasia was observed. CONCLUSIONS: The study results showed nidus obliteration in most pediatric patients who underwent repeat SRS for persistent AVMs. The risks of symptomatic RICs and latency period hemorrhage were quite low. These findings suggest that repeat radiosurgery should be considered when treating pediatric patients with residual AVM after prior SRS. Further study is needed to define the role of repeat SRS more fully in this population.

Intratumoral Hemorrhage in Vestibular Schwannomas After Stereotactic Radiosurgery: Multi-Institutional Study.

BACKGROUND AND OBJECTIVES: Intratumoral hemorrhage (ITH) in vestibular schwannoma (VS) after stereotactic radiosurgery (SRS) is exceedingly rare. The aim of this study was to define its incidence and describe its management and outcomes in this subset of patients. METHODS: A retrospective multi-institutional study was conducted, screening 9565 patients with VS managed with SRS at 10 centers affiliated with the International Radiosurgery Research Foundation. RESULTS: A total of 25 patients developed ITH (cumulative incidence of 0.26%) after SRS management, with a median ITH size of 1.2 cm 3 . Most of the patients had Koos grade II-IV VS, and the median age was 62 years. After ITH development, 21 patients were observed, 2 had urgent surgical intervention, and 2 were initially observed and had late resection because of delayed hemorrhagic expansion and/or clinical deterioration. The histopathology of the resected tumors showed typical, benign VS histology without sclerosis, along with chronic inflammatory cells and multiple fragments of hemorrhage. At the last follow-up, 17 patients improved and 8 remained clinically stable. CONCLUSION: ITH after SRS for VS is extremely rare but has various clinical manifestations and severity. The management paradigm should be individualized based on patient-specific factors, rapidity of clinical and/or radiographic progression, ITH expansion, and overall patient condition.

Consensus-Based Development of a Global Registry for Traumatic Brain Injury: Establishment, Protocol, and Implementation.

BACKGROUND AND OBJECTIVES: Global disparity exists in the demographics, pathology, management, and outcomes of surgically treated traumatic brain injury (TBI). However, the factors underlying these differences, including intervention effectiveness, remain unclear. Establishing a more accurate global picture of the burden of TBI represents a challenging task requiring systematic and ongoing data collection of patients with TBI across all management modalities. The objective of this study was to establish a global registry that would enable local service benchmarking against a global standard, identification of unmet need in TBI management, and its evidence-based prioritization in policymaking. METHODS: The registry was developed in an iterative consensus-based manner by a panel of neurotrauma professionals. Proposed registry objectives, structure, and data points were established in 2 international multidisciplinary neurotrauma meetings, after which a survey consisting of the same data points was circulated within the global neurotrauma community. The survey results were disseminated in a final meeting to reach a consensus on the most pertinent registry variables. RESULTS: A total of 156 professionals from 53 countries, including both high-income countries and low- and middle-income countries, responded to the survey. The final consensus-based registry includes patients with TBI who required neurosurgical admission, a neurosurgical procedure, or a critical care admission. The data set comprised clinically pertinent information on demographics, injury characteristics, imaging, treatments, and short-term outcomes. Based on the consensus, the Global Epidemiology and Outcomes following Traumatic Brain Injury (GEO-TBI) registry was established. CONCLUSION: The GEO-TBI registry will enable high-quality data collection, clinical auditing, and research activity, and it is supported by the World Federation of Neurosurgical Societies and the National Institute of Health Research Global Health Program. The GEO-TBI registry ( https://geotbi.org ) is now open for participant site recruitment. Any center involved in TBI management is welcome to join the collaboration to access the registry.

Comparison of the efficacy of intranasal atomised dexmedetomidine versus intranasal atomised ketamine as a premedication for sedation and anxiolysis in children undergoing spinal dysraphism surgery: A randomized controlled trial.

BACKGROUND: Preoperative anxiety leads to adverse clinical outcomes and long-term maladaptive behavioural changes. The role of intranasal atomised dexmedetomidine and atomised ketamine as premedication to produce sedation and anxiolysis in paediatric neurosurgical patients has not been extensively studied. OBJECTIVE: To study the efficacy of intranasal atomised dexmedetomidine and intranasal atomised ketamine as premedication in producing sedation and facilitating smooth induction in children undergoing spinal dysraphism surgery. DESIGN: A prospective randomised double-blind trial. SETTING: A tertiary teaching hospital. PATIENTS: Sixty-four children aged 1 to 10 years undergoing spinal dysraphism surgery. METHODS: Children were randomised to receive intranasal atomised dexmedetomidine 2.5 µg kg -1 (Group D, n  = 32) and intranasal atomised ketamine 5 mg kg -1 (Group K, n  = 32) 30 min before surgery. OUTCOMES MEASURED: The primary outcome was to compare the level of sedation in both groups using the University of Michigan Sedation Score (UMSS). The secondary outcomes included an assessment of the ease of parental separation, intravenous cannulation and satisfactory mask acceptance along with perioperative vitals (heart rate, blood pressure and oxygen saturation). The incidence of emergence agitation and time to discharge were also noted. RESULTS: The degree of sedation was significantly better in Group D as compared to Group K at 20 min (UMSS, 1.55 ±â€Š0.51 versus 1.13 ±â€Š0.34, difference, -0.406; 95% CI, -0.621 to -0.191; P  = 0.0001) and 30 min (2.32 ±â€Š0.6 versus 1.94 ±â€Š0.50, difference, -0.374; 95% CI, -0.650 to -0.100; P  = 0.007). The ease of parental separation, venous cannulation and mask acceptance ( P  = 0.83, 0.418 and 0.100 respectively) were comparable in both groups. The heart rate was lower in group D at 10, 20 and 30 min post-drug administration but was clinically insignificant. The incidence of emergence agitation and time to discharge was also similar with no adverse events reported. CONCLUSION: Intranasal atomised dexmedetomidine produces greater sedation as compared to intranasal atomised ketamine with comparable ease of parental separation, venous cannulation and mask acceptance with no adverse effects.

Management of mild degenerative cervical myelopathy and asymptomatic spinal cord compression: an international survey.

STUDY DESIGN: Cross-sectional survey. OBJECTIVE: Currently there is limited evidence and guidance on the management of mild degenerative cervical myelopathy (DCM) and asymptomatic spinal cord compression (ASCC). Anecdotal evidence suggest variance in clinical practice. The objectives of this study were to assess current practice and to quantify the variability in clinical practice. METHODS: Spinal surgeons and some additional health professionals completed a web-based survey distributed by email to members of AO Spine and the Cervical Spine Research Society (CSRS) North American Society. Questions captured experience with DCM, frequency of DCM patient encounters, and standard of practice in the assessment of DCM. Further questions assessed the definition and management of mild DCM, and the management of ASCC. RESULTS: A total of 699 respondents, mostly surgeons, completed the survey. Every world region was represented in the responses. Half (50.1%, n = 359) had greater than 10 years of professional experience with DCM. For mild DCM, standardised follow-up for non-operative patients was reported by 488 respondents (69.5%). Follow-up included a heterogeneous mix of investigations, most often at 6-month intervals (32.9%, n = 158). There was some inconsistency regarding which clinical features would cause a surgeon to counsel a patient towards surgery. Practice for ASCC aligned closely with mild DCM. Finally, there were some contradictory definitions of mild DCM provided in the form of free text. CONCLUSIONS: Professionals typically offer outpatient follow up for patients with mild DCM and/or asymptomatic ASCC. However, what this constitutes varies widely. Further research is needed to define best practice and support patient care.

Stereotactic radiosurgery for non-functioning pituitary tumor: a multicenter study of new pituitary hormone deficiency.

BACKGROUND: Stereotactic radiosurgery (SRS) is used to treat recurrent or residual nonfunctioning pituitary neuroendocrine tumors (NFPA). The objective of the study was to assess imaging and development of new pituitary hormone deficiency. METHODS: Patients treated with single-session SRS for a NFPA were included in this retrospective, multicenter study. Tumor control and new pituitary dysfunction were evaluated using Cox analysis and Kaplan-Meier curves. RESULTS: 869 patients (male 476 [54.8%], median age at SRS 52.5 years [Interquartile range (IQR):18.9]) were treated using a median margin dose of 14Gy (IQR:4) for a median tumor volume of 3.4 cc (IQR: 4.3). With a median radiological follow-up of 3.7 years (IQR: 4.8), volumetric tumor reduction occurred in 451 patients (51.9%), stability in 364 (41.9%) and 54 patients (6.2%) showed tumor progression.The probability of tumor control was 95.5% (95% Confidence Interval [CI]: 93.8-97.3) and 88.8% (95%CI: 85.2-92.5) at 5 and 10 years, respectively. A margin dose >14 Gy was associated with tumor control (Hazard Ratio HR:0.33 [95%CI:0.18-0.60], p<0.001).The probability of new hypopituitarism was 9.9% (95% CI: 7.3-12.5) and 15.3% (95% CI:11-19.4) at 5 and 10 years, respectively.A maximum point dose >10 Gy in the pituitary stalk was associated with new pituitary hormone deficiency (HR:3.47, 95% CI:1.95-6.19). The cumulative probability of new cortisol, thyroid, gonadotroph and growth hormone deficiency was 8% (95% CI:3.9-11.9), 8.3% (95% CI:3.9-12.5), 3.5% (95% CI:1.7-5.2), and 4.7% (95% CI:1.9-7.4), respectively at 10 years. CONCLUSION: SRS provides long-term tumor control with a 15.3% risk of hypopituitarism at 10 years.

Clinical outcomes following stereotactic radiosurgery for cerebral cavernous malformations of the basal ganglia and thalamus.

OBJECTIVE: There are few reports of outcomes following stereotactic radiosurgery (SRS) for the management of cerebral cavernous malformations (CCMs) of the basal ganglia or thalamus. Therefore, the authors aimed to clarify these outcomes. METHODS: Centers participating in the International Radiosurgery Research Foundation were queried for CCM cases managed with SRS from October 2001 to February 2021. The primary outcome of interest was hemorrhage-free survival (HFS) with a secondary outcome of symptomatic adverse radiation events (AREs). Assessment of the association of prognostic factors with HFS was conducted via Kaplan-Meier analysis and log-rank test. Chi-square tests were conducted to assess potential factors associated with the incidence of AREs. RESULTS: Seventy-three patients were identified. The median patient age was 43.5 years (range 4.4-79.5 years). Fifty-nine (80.8%) patients had hemorrhage prior to SRS. The median treatment volume was 0.9 cm3 (range 0.07-10.1 cm3) with a median margin prescription dose (MPD) of 12 Gy (range 10-20 Gy). One-, 3-, 5-, and 10-year HFS were 93.0%, 89.9%, 89.9%, and 83.0%, respectively, with one hemorrhage-related death approximately 1 year after SRS and nearly 60% and 30% of patients having improvement or stability of symptoms, respectively. There was no correlation between lesion size or MPD and HFS. Seven (9.6%) patients experienced AREs (MPDs > 12 Gy in all cases). Lesion size > 1.0 cm3 was correlated with the incidence of an ARE (p = 0.019). Forty-two (93.3%) of 45 patients treated with an MPD ≤ 12 Gy experienced neither hemorrhage nor AREs following SRS versus 17 (60.7%) of 28 patients treated with an MPD > 12 Gy (p = 0.0006). CONCLUSIONS: SRS is a reasonable treatment strategy and confers clinical stability or improvement and hemorrhage avoidance in patients harboring CCMs of the basal ganglia or thalamus. An MPD of approximately 12 Gy is recommended for the management of CCM.

Effect of cerebral arteriovenous malformation location on outcomes of repeat, single-fraction stereotactic radiosurgery: a matched-cohort analysis.

OBJECTIVE: Patients with deep-seated arteriovenous malformations (AVMs) have a higher rate of unfavorable outcome and lower rate of nidus obliteration after primary stereotactic radiosurgery (SRS). The aim of this study was to evaluate and quantify the effect of AVM location on repeat SRS outcomes. METHODS: This retrospective, multicenter study involved 505 AVM patients managed with repeat, single-session SRS. The endpoints were nidus obliteration, hemorrhage in the latency period, radiation-induced changes (RICs), and favorable outcome. Patients were split on the basis of AVM location into the deep (brainstem, basal ganglia, thalamus, deep cerebellum, and corpus callosum) and superficial cohorts. The cohorts were matched 1:1 on the basis of the covariate balancing score for volume, eloquence of location, and prescription dose. RESULTS: After matching, 149 patients remained in each cohort. The 5-year cumulative probability rates for favorable outcome (probability difference -18%, 95% CI -30.9 to -5.8%, p = 0.004) and AVM obliteration (probability difference -18%, 95% CI -30.1% to -6.4%, p = 0.007) were significantly lower in the deep AVM cohort. No significant differences were observed in the 5-year cumulative probability rates for hemorrhage (probability difference 3%, 95% CI -2.4% to 8.5%, p = 0.28) or RICs (probability difference 1%, 95% CI -10.6% to 11.7%, p = 0.92). The median time to delayed cyst formation was longer with deep-seated AVMs (deep 62 months vs superficial 12 months, p = 0.047). CONCLUSIONS: AVMs located in deep regions had significantly lower favorable outcomes and obliteration rates compared with superficial lesions after repeat SRS. Although the rates of hemorrhage in the latency period and RICs in the two cohorts were comparable, delayed cyst formation occurred later in patients with deep-seated AVMs.

Silent Corticotroph Staining Pituitary Neuroendocrine Tumors: Prognostic Significance in Radiosurgery.

BACKGROUND AND OBJECTIVES: There is conflicting evidence on the significance of adrenocorticotrophic hormone (ACTH) staining in the prognosis of nonfunctioning pituitary neuroendocrine tumors (NFpitNETs). The objective of this study was to define the effect of ACTH immunostaining on clinical and radiographic outcomes of stereotactic radiosurgery (SRS) for NFpitNETs. METHODS: This retrospective, multicenter study included patients managed with SRS for NFpitNET residuals. The patients were divided into 2 cohorts: (1) silent corticotroph (SC) for NFpitNETs with positive ACTH immunostaining and (2) non-SC NFpitNETs. Rates of local tumor control and the incidence of post-treatment pituitary and neurological dysfunction were documented. Factors associated with radiological and clinical outcomes were also analyzed. RESULTS: The cohort included 535 patients from 14 centers with 84 (15.7%) patients harboring silent corticotroph NFpitNETs (SCs). At last follow-up, local tumor progression occurred in 11.9% of patients in the SC compared with 8.1% of patients in the non-SC cohort (P = .27). No statistically significant difference was noted in new-onset hypopituitarism rates (10.7% vs 15.4%, P = .25) or visual deficits (3.6% vs 1.1%, P = .088) between the 2 cohorts at last follow-up. When controlling for residual tumor volume, maximum dose, and patient age and sex, positive ACTH immunostaining did not have a significant correlation with local tumor progression (hazard ratio = 1.69, 95% CI = 0.8-3.61, P = .17). CONCLUSION: In contemporary radiosurgical practice with a single fraction dose of 8-25 Gy (median 15 Gy), ACTH immunostaining in NFpitNETs did not appear to confer a significantly reduced rate of local tumor control after SRS.

Selected-Lesion Stereotactic Radiosurgery (SL-SRS) as a Novel Strategy in the Treatment of Patients With Multiple Brain Metastases.

INTRODUCTION: With the diminishing use of whole-brain radiotherapy (WBRT), there is increasing debate regarding the maximum number of brain metastases that should be treated with stereotactic radiosurgery (SRS). In patients with >10-15 lesions, some groups are proposing a new approach - selected-lesion SRS (SL-SRS) - where only a subset of intracranial lesions are chosen for irradiation. This study is an initial look into this practice. METHODS: This is a cross-sectional exploratory survey study. A survey of 19 questions was created by the International Radiosurgery Research Foundation (IRRF) using open-ended and multiple-choice style questions on SL-SRS practices and indications with the goal of qualitatively understanding how SL-SRS is being implemented worldwide. The survey was distributed to physicians in the United States (US) and internationally who are members of the IRRF and who perform SRS frequently. Ten out of 50 IRRF institutions provided responses reflecting the practices of 16 physicians. RESULTS: SL-SRS is being performed at 8/10 institutions. The most common reasons for using SL-SRS included patients with prior WBRT, patients with progressing systemic disease with central nervous system (CNS)-penetrating or immunotherapies available, specific requests from medical oncology, and cooperative studies using this approach. Lesion size was cited as the most important factor when choosing to irradiate any single lesion. The majority of respondents reported 30 mm and 40 mm as size cutoffs (by largest dimension) for treatment of a lesion in eloquent and non-eloquent locations, respectively. Eloquence of lesion location and attributable symptoms were also considered important. Progression of untreated lesions was the most common reason reported for bringing patients back for additional treatment. CONCLUSION: The responses to this survey show that SL-SRS is being used, allowing for small/asymptomatic brain metastases to be left safely unirradiated. It is currently used in patients who have >10-15 lesions with prior WBRT, those with progression of extracranial disease but with acceptable systemic treatment options, and those with poor functional status. The incorporation of this new approach into clinical trials should be considered for the safe study of the efficacy of new CNS-penetrating systemic therapies.

An international, prospective observational study on traumatic brain injury epidemiology study protocol: GEO-TBI: Incidence.

Background: The epidemiology of traumatic brain injury (TBI) is unclear - it is estimated to affect 27-69 million individuals yearly with the bulk of the TBI burden in low-to-middle income countries (LMICs). Research has highlighted significant between-hospital variability in TBI outcomes following emergency surgery, but the overall incidence and epidemiology of TBI remains unclear. To address this need, we established the Global Epidemiology and Outcomes following Traumatic Brain Injury (GEO-TBI) registry, enabling recording of all TBI cases requiring admission irrespective of surgical treatment. Objective: The GEO-TBI: Incidence study aims to describe TBI epidemiology and outcomes according to development indices, and to highlight best practices to facilitate further comparative research. Design: Multi-centre, international, registry-based, prospective cohort study. Subjects: Any unit managing TBI and participating in the GEO-TBI registry will be eligible to join the study. Each unit will select a 90-day study period. All TBI patients meeting the registry inclusion criteria (neurosurgical/ICU admission or neurosurgical operation) during the selected study period will be included in the GEO-TBI: Incidence. Methods: All units will form a study team, that will gain local approval, identify eligible patients and input data. Data will be collected via the secure registry platform and validated after collection. Identifiers may be collected if required for local utility in accordance with the GEO-TBI protocol. Data: Data related to initial presentation, interventions and short-term outcomes will be collected in line with the GEO-TBI core dataset, developed following consensus from an iterative survey and feedback process. Patient demographics, injury details, timing and nature of interventions and post-injury care will be collected alongside associated complications. The primary outcome measures for the study will be the Glasgow Outcome at Discharge Scale (GODS) and 14-day mortality. Secondary outcome measures will be mortality and extended Glasgow Outcome Scale (GOSE) at the most recent follow-up timepoint.

Traumatic brain injury (TBI) is a significant global health problem, which affects 27­69 million people every year. After-effects of TBI commonly affect the injured individuals for years. Most patients who sustain a TBI are from developing countries. Research has shown that there are differences in patients' recovery after TBI between countries and hospitals. The causes of these differences are unclear and tackling them could improve TBI treatment worldwide. To address this need, we have recently established the Global Epidemiology and Outcomes Following Traumatic Brain Injury (GEO-TBI) registry. The international collaborative registry aims to collect data related to the causes, treatments and outcomes related to TBI patients. This data will hopefully enable future research to elucidate the causes of the recovery differences between hospitals, which could lead to improved patient outcomes. The GEO-TBI: Incidence study collects data from all TBI patients that are admitted to participating hospitals or undergo a neurosurgical operation due to TBI during a 90-day period. This study looks at the patient's recovery at discharge using the Glasgow Outcome at Discharge Scale (GODS), and at the 2-week mortality. In addition, the study also evaluates recovery at the most recent follow-up timepoint. We hope that this information will enhance our understanding on the causes, treatments, and commonness of TBI. The study results will also help local hospitals compare their treatment results to an international standard.