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Background  Resection of skull base malignancies poses complex pathological and treatment-related morbidities. Recent technological advancements of endoscopic endonasal surgery (EES) offer the ability to reexamine traditional treatment paradigms with endoscopic procedures. The utility of EES was quantitatively examined in a longitudinal series with attention to morbidities and postoperative outcomes. Methods  A single-center retrospective review was performed of all malignant sinonasal tumors from 2010 to 2018. Patients with purely EES were selected for analysis. Disease features, resection extent, complications, adjuvant treatment, recurrence, and survivability were assessed. Despite the mixed pathological cohort, analysis was performed to identify technical aspects of resection. Results  A total of 68 patients (47.6% males and 52.4% females, average age: 60.3 years) were included. A diversity of histotypes included clival chordoma (22.1%), olfactory neuroblastoma (14.7%), squamous cell carcinoma (11.8%), and adenoid cystic carcinoma (11.8%). Gross total resection (GTR) was achieved in 83.8% of cases. Infection (4.4%) and cerebrospinal fluid leak (1.5%) were the most common postoperative complications. Total 46 patients (67.6%) underwent adjuvant treatment. The average time between surgery and initiation of adjunctive surgery was 55.7 days. Conclusion  In our 8-year experience, we found that entirely endoscopic resection of mixed pathology of malignant skull base tumors is oncologically feasible and can be accomplished with high GTR rates. There may be a role for EES to reduce operative morbidity and attenuate time in between surgery and adjuvant treatment, which can be augmented through recent mixed reality platforms. Future studies are required to systematically compare the outcomes with those of open surgical approaches. [ABSTRACT FROM AUTHOR]

Objective  There is increasing interest in investigating the utility of 7 Tesla (7 T) magnetic resonance imaging (MRI) for imaging of skull base tumors. The present study quantifies visualization of tumor features and adjacent skull base anatomy in a homogenous cohort of pituitary adenoma patients. Methods  Eighteen pituitary adenoma patients were scanned at 7 T in this prospective study. All patients had reference standard-of-care clinical imaging at either 3 T (7/18, 39%) or 1.5 T (11/18, 61%). Visualization of tumor features and conspicuity of arteries and cranial nerves (CNs) was rated by an expert neuroradiologist on 7 T and clinical field strength MRI. Overall image quality and severity of image artifacts were also characterized and compared. Results  Ability to visualize tumor features did not differ between 7 T and lower field MRI. Cranial nerves III, IV, and VI were better detected at 7 T compared with clinical field strength scans. Cranial nerves III, IV, and VI were also better detected at 7 T compared with only 1.5 T, and CN III was better visualized at 7 T compared with 3 T MRI. The ophthalmic arteries and posterior communicating arteries (PCOM) were better detected at 7 T compared with clinical field strength imaging. The 7 T also provided better visualization of the ophthalmic arteries compared with 1.5 T scans. Conclusion  This study demonstrates that 7 T MRI is feasible at the skull base and identifies various CNs and branches of the internal carotid artery that were better visualized at 7 T. The 7 T MRI may offer important preoperative information that can help to guide resection of pituitary adenoma and reduce operative morbidity. [ABSTRACT FROM AUTHOR]

Objective  This article aims to characterize 14 patients who underwent purely endoscopic surgical debridement of acute invasive skull base fungal rhinosinusitis, and to evaluate postoperative outcomes and risk for recurrence. Design  Retrospective cohort study. Setting  Tertiary single-institution neurosurgery department. Participants  We performed a retrospective analysis of all patients with skull base fungal infections treated with a purely endoscopic surgical approach at Mount Sinai Hospital from 1998 to 2018. Main Outcome Measures  Clinical presentation, number of recurrences, and mortality rate. Results  The most common underlying medical comorbidities were hematologic malignancy in 8 (57.1%) patients and poorly controlled diabetes mellitus in 7 (50%) patients. Presenting symptoms included headache (50%), eye pain (35.7%), facial pain (28.6%), visual changes (21.4%), and nasal congestion (14.3%). The fungal organisms identified on culture were Aspergillus (42.9%), Mucorales (28.6%), Fusarium (14.3%), Penicillium (7.1%), and unspecified (7.1%). Eight (57.1%) patients developed recurrence and required multiple surgical debridements. Patients who had only a hematologic malignancy were more likely to require multiple surgical debridements compared with those who did not have a hematologic malignancy or those who had both hematologic malignancy and underlying diabetes mellitus (p  = 0.03). The mortality rate from surgery was 42.9%. Conclusion  Surgical endoscopic intervention is an option for definitive management of acute invasive skull base fungal rhinosinusitis; however, postoperative mortality and risk of recurrence requiring additional surgical interventions remains high. Patients with hematologic malignancy may be more susceptible to recurrent infection requiring multiple surgical debridements. We recommend early aggressive multimodal treatment. Multiple debridements may be warranted in most cases; close clinical surveillance is needed during neurosurgical intervention. [ABSTRACT FROM AUTHOR]

Background: Biliary tract cancers (BTCs) are highly fatal malignancies that make up less than 1% of all cancers. BTC is often diagnosed at an unresectable stage; surgical resection remains the only definitive treatment. Brain metastases (BMs) from BTC are extremely rare, and few studies on patients with BMs from BTC exist. The aim of this study was to identify clinical characteristics associated with poor prognosis for patients with BMs from BTC. Materials and Methods: We performed a retrospective review of electronic medical records for patients with BMs from BTC managed at Mount Sinai Hospital from 2000 to 2017. Data on patient characteristics, magnetic resonance imaging findings, treatment regimens, and clinical outcomes were analyzed. Results: We identified 1,910 patients with BTC. Nine patients developed BMs, with an incidence of 0.47%. Of these nine patients, six had intrahepatic cholangiocarcinoma, two had extrahepatic cholangiocarcinoma, and one had gallbladder cancer. Six (66.7%) patients had one BM, one (11.1%) patient had two BMs, and two (22.2%) patients had three or more BMs. Four (44.4%) patients underwent BM resection, and seven (77.8%) received BM radiation. Median overall survival from time of BM diagnosis was 3.8 months (95% confidence interval 0.1–16.9). Conclusion: Development of BMs from BTC is rare; however, prognosis is less than 4 months. BM diagnosis can occur within 2 years of primary diagnosis. As targeted therapeutics emerge, future studies ought to focus on identifying genomic BM markers associated with BTC subtypes. Implications for Practice: In the largest retrospective study of biliary tract cancer brain metastases, the clinical presentation and outcomes are reported of nine patients with an extremely rare clinical entity. The genomic literature and potential therapeutic targets for these patients with limited treatment options is comprehensively and exhaustively discussed. A better understanding of clinical outcomes of patients with biliary tract cancer who develop brain metastases. This article expands on the existing literature by describing outcomes for patients who developed brain metastases from biliary tract cancer within the context of the genomic era. [ABSTRACT FROM AUTHOR]

Introduction Pituitary neoplasms are benign entities that require distinct diagnostic and treatment considerations. Recent advances in endoscopic transsphenoidal surgery have resulted in shorter lengths of stay (LOS). We implemented a postoperative day (POD) 1 discharge paradigm involving a multidisciplinary approach and detailed preoperative evaluation and review of both medical and socioeconomic factors. Methods The experience of a single neurosurgeon/ears, nose, throat (ENT) team was reviewed, generating a preliminary retrospective database of the first 30 patients who underwent resection of pituitary lesions under the POD 1 discharge paradigm. We assessed multiple axes from their preoperative, in-house, and postoperative care. Results There were 14 men and 16 women with an average age of 53.8 years (range: 27-76 years). There were 22 nonsecretory and 8 secretory tumors with average size of 2.80 cm (range: 1.3-5.0 cm). All 30 patients underwent preoperative ENT evaluation. Average LOS was 1.5 ± 0.7 days. A total of 18 of 30 patients were discharged on POD 1. The insurance status included 15 with public insurance such as emergency Medicaid and 15 with private insurance. Four patients had transient diabetes insipidus (DI); none had permanent DI. Overall, 28 of 30 patients received postoperative steroids. Factors that contributed to LOS > 1 day included public insurance status, two or more medical comorbidities, diabetes mellitus, transient panhypopituitarism, and DI. Conclusion The implementation of a POD 1 discharge plan for pituitary tumors is feasible and safe for elective patients. This implementation requires the establishment of a dedicated Pituitary Center model with experienced team members. The consistent limitation to early discharge was socioeconomic status. Efforts that incorporate the analysis of social disposition parameters with proper management of clinical sequelae are crucial to the maintenance of ideal LOS and optimal patient outcomes. [ABSTRACT FROM AUTHOR]

Chiari malformation type I (CM-1) is a complex disorder in which tonsillar herniation through the foramen magnum (FM) manifests with a spectrum of clinical symptoms. This work analyzes morphometric and volumetric characteristics of CM-1 patients. With institutional review board approval, we retrospectively reviewed a total of 72 adult CM-1 patients and 26 healthy adult volunteers who underwent volumetric magnetic resonance brain imaging. Clinical data were retrospectively extracted from the electronic medical record. We analyzed multidimensional morphometric and volumetric features within the posterior cranial fossa and correlated these features with syrinx formation and the decision to undergo surgical decompression. In our study, CM-1 patients had decreased cerebellar (CBL), brainstem, and fourth ventricular volumes but larger tonsillar volume with increased total tonsillar length. CM-1 patients who underwent surgery had significantly more neural tissue within the cross-sectional area of the cisterna magna. Logistic regression demonstrated that combining neural tissue at the FM with CBL and fourth ventricular volumes led to a great degree of correlation with syrinx formation (area under the curve: 0.911). Our findings suggest that the amount of tissue at the FM correlates with CM-1 patients who underwent decompressive surgery, more so than tonsillar length. Additionally, the combination of neural tissue at the FM, CBL, and fourth ventricular volumes led to a great degree of correlation with syrinx formation. Together, these findings suggest that a global compressive phenomenon within the posterior fossa leads to CM-1 symptomatology and syrinx formation. [ABSTRACT FROM AUTHOR]

This study aims to develop and evaluate radiomics-based machine learning (ML) models for predicting meningioma grades using multiparametric magnetic resonance imaging (MRI). The study utilized the BraTS-MEN dataset's training split, including 698 patients (524 with grade 1 and 174 with grade 2–3 meningiomas). We extracted 4872 radiomic features from T1, T1 with contrast, T2, and FLAIR MRI sequences using PyRadiomics. LASSO regression reduced features to 176. The data was split into training (60%), validation (20%), and test (20%) sets. Five ML algorithms (TabPFN, XGBoost, LightGBM, CatBoost, and Random Forest) were employed to build models differentiating low-grade (grade 1) from high-grade (grade 2–3) meningiomas. Hyperparameter tuning was performed using Optuna, optimizing model-specific parameters and feature selection. The CatBoost model demonstrated the best performance, achieving an area under the receiver operating characteristic curve (AUROC) of 0.838 [95% confidence interval (CI): 0.689–0.935], precision of 0.492 (95% CI: 0.371–0.623), recall of 0.838 (95% CI: 0.689–0.935), F1 score of 0.620 (95% CI: 0.495–0.722), accuracy of 0.729 (95% CI: 0.650–0.800), an area under the precision-recall curve (AUPRC) of 0.620 (95% CI: 0.433–0.753), and Brier score of 0.156 (95% CI: 0.122-0.200). Other models showed comparable performance, with mean AUROCs ranging from 0.752 to 0.784. The radiomics-based ML approach presented in this study showcases the potential for non-invasive and pre-operative grading of meningiomas using multiparametric MRI. Further validation on larger and independent datasets is necessary to establish the robustness and generalizability of these findings. [ABSTRACT FROM AUTHOR]

Medically refractory cases of trigeminal neuralgia often require treatment escalation. Surgical options include microvascular decompression and percutaneous ablation. This paper provides a bibliometric analysis of the most influential articles on the surgical management of trigeminal neuralgia. The Web of Science database was queried to identify the top 100 cited articles concerning surgical treatment of trigeminal neuralgia. The search terms used included ALL=(("trigeminal neuralgia" OR "tic douloureux" OR "Fothergill's disease" OR "Trifacial neuralgia") AND ("surgical treatment" OR "surgical management" OR "surgery" OR "neurosurgery") NOT ("radiosurgery" OR "gamma knife")). The extracted variables included the first and senior author names, journal, publication year, institution, and surgical modality. Our bibliometric search yielded 2104 studies, with 41,502 citations overall. Within the top 100 articles, Zakrzewska had the most first author papers (n = 5), and Burchiel had the most senior author papers (n = 6). The Massachusetts General Hospital was the most represented institution (n = 5). The United States was the most represented country (51%). Microvascular decompression was the most studied surgical strategy (51%), followed by percutaneous radiofrequency coagulation (9%), balloon/nerve compression (7%), and glycerol rhizolysis (7%). Some studies assessed multiple treatment modalities (22%). The types of studies included retrospective articles (58%), prospective articles (26%), reviews (10%), anatomic studies (2%), and basic science (1%). Neurosurgery (35%) and the Journal of Neurosurgery (33%) were the most represented journals. The current literature consists of retrospective reviews and mostly describes microvascular decompression for trigeminal neuralgia. Future studies should include further characterization of other surgical modalities such as percutaneous radiofrequency thermocoagulation, glycerol injection, and balloon compression. [ABSTRACT FROM AUTHOR]

Purpose: The oncologic outcomes for atypical meningiomas can be poor. Generally, patients that have had a prior recurrence have a substantially elevated risk of a future recurrence. Additionally, certain tumor genomic profiles have been shown as markers of poor prognosis. We sought to characterize the genomic differences between primary and recurrent tumors as well as assess if those differences had implications on recurrence. Methods: We identified primary and recurrent gross totally resected WHO grade II meningiomas with > 30 days of post-surgical follow-up at our institution. For genes with a prevalence of > 5% in the cohort, we compared the mutational prevalence in primary and recurrent tumors. For a gene of interest, we assessed the time to radiographic recurrence using adjusted cox-regression. Results: We identified 88 meningiomas (77 primary, 16 recurrent) with a median follow-up of 5.33 years. Mutations in ARID1A found in association with recurrent tumors (7/16 recurrent tumors vs 5/72 primary tumors, p < 0.001). In the whole cohort, mutations in ARID1A were not associated with alterations in time to recurrence after adjusting for recurrence status (p = 0.713). When restricted to primary tumors, ARID1A is associated with a 625% increase in the hazard of recurrence (HR = 7.26 [1.42–37.0]; p = 0.017). Conclusion: We demonstrate mutations in ARID1A, a chromatin remodeling gene, in a higher prevalence in recurrent tumors. We further demonstrate that when mutations in ARID1A are present in primary atypical meningiomas, these tumors tend to have worse prognosis. Further prospective study may validate ARID1A as a prognostic marker. [ABSTRACT FROM AUTHOR]

Abstract Purpose Methods Results Conclusions Meningiomas occur more frequently in older adults, with the incidence rates increasing from 5.8/100,000 for adults 35-44 years old to 55.2/100,000 for those 85+. Due to the increased risk of surgical management in older adults, there is a need to characterize the risk factors for aggressive disease course to inform management decisions in this population. We therefore sought to determine age-stratified relationships between tumour genomics and recurrence after resection of atypical meningiomas.We identified 137 primary and recurrent Grade 2 meningiomas from our existing meningioma genomic sequencing database. We examined the differential distribution of genomic alterations in those older than 65 compared to younger. We then performed an age stratified survival analysis to model recurrence for a mutation identified as differentially present.In our cohort of 137 patients with grade 2 meningiomas, alterations in NF2 were present at a higher rate in older adults compared to younger (37.8% in < 65 vs. 55.3% in > 65; recurrence adjusted p-value =0.04). There was no association between the presence of NF2 and recurrence in the whole cohort. In the age-stratified model for those less than 65 years old, there was again no relationship. For patients in the older age stratum, there is a relationship between NF2 and worsened recurrence outcomes (HR = 3.64 (1.125 − 11.811); p = 0.031).We found that mutations in NF2 were more common in older adults. Further, the presence of mutant NF2 was associated with an increased risk of recurrence in older adults. [ABSTRACT FROM AUTHOR]

Purpose: While SWI/SNF chromatin remodeling complex alterations occur in approximately 20% of cancer, the frequency and potential impact on clinical outcomes in meningiomas remains to be comprehensively elucidated. Methods: A large series of 255 meningiomas from a single institution that was enriched for high grade and recurrent lesions was identified. We performed next-generation targeted sequencing of known meningioma driver genes, including NF2, AKT1, PIK3CA, PIK3R1, and SMO and SWI/SNF chromatin remodeling complex genes, including ARID1A, SMARCA4, and SMARCB1 in all samples. Clinical correlates focused on clinical presentation and patient outcomes are presented. Results: The series included 63 grade I meningiomas and 192 high-grade meningiomas, including 173 WHO grade II and 19 WHO grade III. Samples from recurrent surgeries comprised 37.3% of the series. A total of 41.6% meningiomas were from the skull base. NF2, AKT1, PIK3CA, PIK3R1, and SMO were mutated in 40.8, 7.1, 3.5, 3.9, and 2.4% of samples, respectively. ARID1A, SMARCA4, and SMARCB1 mutations were observed in 17.3, 3.5, and 5.1% of samples, respectively. A total of 68.2% of ARID1A-mutant meningiomas harbored a p.Gln1327del in-frame deletion. ARID1A mutations were seen in 19.1% of Grade I, 16.8% of Grade II, and 15.8% of Grade III meningiomas (P = 0.9, Fisher's exact). Median overall survival was 16.3 years (95% CI 10.9, 16.8). With multivariable analysis, the presence of an ARID1A mutation was significantly associated with a 7.421-fold increased hazard of death (P = 0.04). Conclusion: ARID1A mutations occur with similar frequency between low and high-grade meningiomas, but ARID1A mutations are independently prognostic of worse prognosis beyond clinical and histopathologic features. [ABSTRACT FROM AUTHOR]

Introduction: The density and distribution of the tumor immune microenvironment associated with brain metastases (BM) from gynecologic malignancies are unknown and have not been previously reported. We sought to describe the clinical features of a cohort of patients with BM from gynecologic malignancies and to characterize the tumor immune microenvironment from available archival surgical specimens. Methods: We performed a retrospective review of electronic medical records from 2002 to 2018 for patients with BM from gynecologic malignancies. Data on patient characteristics, treatment regimens, and clinical outcomes were procured. CD4, CD8, CD45RO, CD68, CD163, and FOXP3 immunohistochemistry were evaluated from available archival surgical specimens from primary disease site and neurosurgical resection. Results: A cohort of 44 patients with BM from gynecologic malignancies was identified, 21 (47.7%) endometrial primaries and 23 (52.3%) ovarian primaries. Tumor-infiltrating lymphocytes (TILs) and tumor-associated macrophages (TAMs) were evaluated in 13 primary cases and 15 BM cases. For the 13 primary cases, CD4+ TILs were evident in 76.9% of cases, CD8+ in 92.3%, CD45RO+ in 92.3%, and FOXP3+ in 46.2%, as well as CD68+ TAMs in 100% and CD163+ in 100%. For the 15 BM cases, CD4+ TILs were evident in 60.0% of cases, CD8+ in 93.3%, CD45RO+ in 73.3%, and FOXP3+ in 35.7%, as well as CD68+ TAMs in 86.7% and CD163+ in 100%. Conclusion: An active tumor immune microenvironment is present with similar distribution in the primary disease site and BM from patients with gynecologic malignancies. [ABSTRACT FROM AUTHOR]

Background: Trigeminal Neuralgia (TN) is a chronic neurological disease that is strongly associated with neurovascular compression (NVC) of the trigeminal nerve near its root entry zone. The trigeminal nerve at the site of NVC has been extensively studied but limbic structures that are potentially involved in TN have not been adequately characterized. Specifically, the hippocampus is a stress-sensitive region which may be structurally impacted by chronic TN pain. As the center of the emotion-related network, the amygdala is closely related to stress regulation and may be associated with TN pain as well. The thalamus, which is involved in the trigeminal sensory pathway and nociception, may play a role in pain processing of TN. The objective of this study was to assess structural alterations in the trigeminal nerve and subregions of the hippocampus, amygdala, and thalamus in TN patients using ultra-high field MRI and examine quantitative differences in these structures compared with healthy controls. Methods: Thirteen TN patients and 13 matched controls were scanned at 7-Tesla MRI with high resolution, T1-weighted imaging. Nerve cross sectional area (CSA) was measured and an automated algorithm was used to segment hippocampal, amygdaloid, and thalamic subregions. Nerve CSA and limbic structure subnuclei volumes were compared between TN patients and controls. Results: CSA of the posterior cisternal nerve on the symptomatic side was smaller in patients (3.75 mm2) compared with side-matched controls (5.77 mm2, p = 0.006). In TN patients, basal subnucleus amygdala volume (0.347 mm3) was reduced on the symptomatic side compared with controls (0.401 mm3, p = 0.025) and the paralaminar subnucleus volume (0.04 mm3) was also reduced on the symptomatic side compared with controls (0.05 mm3, p = 0.009). The central lateral thalamic subnucleus was larger in TN patients on both the symptomatic side (0.033 mm3) and asymptomatic side (0.035 mm3), compared with the corresponding sides in controls (0.025 mm3 on both sides, p = 0.048 and p = 0.003 respectively). The inferior and lateral pulvinar thalamic subnuclei were both reduced in TN patients on the symptomatic side (0.2 mm3 and 0.17 mm3 respectively) compared to controls (0.23 mm3, p = 0.04 and 0.18 mm3, p = 0.04 respectively). No significant findings were found in the hippocampal subfields analyzed. Conclusions: These findings, generated through a highly sensitive 7 T MRI protocol, provide compelling support for the theory that TN neurobiology is a complex amalgamation of local structural changes within the trigeminal nerve and structural alterations in subnuclei of limbic structures directly and indirectly involved in nociception and pain processing. [ABSTRACT FROM AUTHOR]

Purpose: Meningiomas are the most common primary central nervous system tumor. Emerging data supports that higher mutational burden portends worse clinical outcomes in meningiomas. However, there is a lack of imaging biomarkers that are associated with tumor genomics in meningiomas. Methods: We performed next-generation targeted sequencing in a cohort of 75 primary meningiomas and assessed preoperative imaging for tumor volume and peritumoral brain edema (PTBE). An Edema Index was calculated. Results: Meningiomas that were high grade (WHO grade II or grade III) had significantly larger tumor volume and were more likely to present with PTBE. Moreover, PTBE was associated with brain invasion on histopathology and reduced overall survival. There was a direct association between Edema Index and mutational burden. For every one increase in Edema Index, the number of single nucleotide variants increased by 1.09-fold (95% CI: 1.02, 1.2) (P = 0.01). Conclusion: These data support that Edema Index may serve as a novel imaging biomarker that can inform underlying mutational burden in patients with meningiomas. [ABSTRACT FROM AUTHOR]

Background: The tumor microenvironment is an emerging biomarker of underlying genomic heterogeneity and response to immunotherapy-based treatment regimens in solid malignancies. How tumor mutational burden influences the density, distribution, and presence of a localized immune response in meningiomas is unknown. Methods: Representative hematoxylin and eosin slides were reviewed at 40X to assess for the density of inflammatory cells. Lymphocytes and macrophages were quantified in the following ordinal manner: 0 = not present, 1 = 1–25 cells present, and 2 = greater than 26 cells present. Immune cell infiltrate grade was scored for both scattered and aggregated distributions. Next generation targeted sequencing was performed on all meningiomas included in this study. Results: One hundred and forty-five meningiomas were evaluated in this study. Lymphocytes were observed in both scattered (95.9%) and aggregated (21.4%) distributions. A total of 115 (79.3%) meningiomas had 1–25 scattered lymphocytes, and 24 (16.6%) had > 25 scattered lymphocytes, and 6 (4.1%) had no scattered lymphocytes. Twenty (13.8%) meningiomas had 1–25 aggregated lymphocytes. Eleven (7.6%) had > 25 aggregated lymphocytes and 114 (78.6%) had no aggregated lymphocytes. Six (4.1%) meningiomas had 1–25 aggregated macrophages, 5 (3.4%) had > 25 aggregated macrophages, and 134 (92.4%) had no aggregated macrophages. Density of aggregated lymphocytes and aggregated macrophages were associated with higher tumor grade, P = 0.0071 and P = 0.0068, respectively. Scattered lymphocyte density was not associated with meningioma grade. The presence of scattered lymphocytes was associated with increased tumor mutational burden. Meningiomas that did not have scattered lymphocytes had a mean number of single mutations of 2.3 ± 2.9, compared with meningiomas that had scattered lymphocytes, 6.9 ± 20.3, P = 0.03. NF2 mutations were identified in 59 (40.7%) meningiomas and were associated with increased density of scattered lymphocytes. NF2 mutations were seen in 0 (0%) meningiomas that did not have scattered lymphocytes, 46 (40.0%) meningiomas that had 1–25 scattered lymphocytes, and 13 (54.2%) meningiomas that had > 25 scattered lymphocytes, P = 0.046. Conclusions: Our findings suggest that distribution of immune cell infiltration in meningiomas is associated with tumor mutational burden. NF2 mutational status was associated with an increasing density of scattered lymphocytes. As the role of immunotherapy in meningiomas continues to be elucidated with clinical trials that are currently underway, these results may serve as a novel biomarker of tumor mutational burden in meningiomas. [ABSTRACT FROM AUTHOR]

Seven-Tesla (7T) magnetic resonance imaging (MRI) has demonstrated value for evaluating a variety of intracranial diseases. However, its utility in trigeminal neuralgia has received limited attention. The authors of the present study applied ultra-high field multimodal MRI to two representative patients with secondary trigeminal neuralgia due to epidermoid tumors to illustrate the possible clinical and surgical advantages of 7T compared with standard clinical strength imaging. Techniques included co-registration of multiple 7T sequences to optimize the detection of potential concurrent neurovascular and neoplasm-derived compression. 7T MRI studies were performed using a whole body scanner. Two- and three-dimensional renderings of potential neurovascular conflict were created by co-registering time-of-flight angiography and T2-weighted turbo spin echo images in MATLAB and GE software. Detailed comparisons of the various field strength images were provided by a collaborating neuroradiologist (B.D.). 7T MRI clearly illustrated minute tumor-adjacent vasculature. In contrast, conventional, low-field imaging did not consistently provide adequate details to distinguish cerebrospinal fluid pulsatility from vessels. The tumor margins, although distinct from the trigeminal nerve fibers at 7T, blended with those of the surrounding structures at 3T. Two- and three-dimensional co-registration of time-of-flight angiography with T2-weighted MRI suggested that delicate, intervening vasculature may have contributed to these illustrative patients' symptomatology. 7T provided superior visualization of vital landmarks and subtle nerve and vessel features. Co-registration of various advanced 7T modalities may help to resolve complex disease etiologies. Future studies should explore the extent to which this dual etiology might persist across tumor types and utilize diffusion-based techniques to quantify what microstructural differences might exist between patients with trigeminal neuralgia from varying etiologies. [ABSTRACT FROM AUTHOR]

Purpose: Pituitary adenomas are common CNS tumors that can cause endocrine dysfunction due to hormone oversecretion and by mass effect on the normal gland. The study of pituitary adenomas and adjacent sellar anatomy with high-resolution 7 T MRI may further characterize endocrine dysfunction. The purpose of this study was to determine the efficacy of 7 T MRI in identifying radiological markers for endocrine function. Methods: MR images obtained in 23 patients with pituitary adenomas were reviewed by consensus between three neuroradiologists. Landmarks and criteria were devised to measure radiological features of stalk, tumor, and normal gland. Fischer's exact tests and nominal logistic regression were performed. Results: Mean cross-sectional area of the stalk just below the infundibular recess was 6.3 ± 3.7 mm2. Mean curvature and deviation angles were 34.2° ± 23.2° and 29.7° ± 17.3°, respectively. Knosp scores obtained differed between 7 T and lower field strength scans (P < 0.0001 [right] and P = 0.0006 [left]). Ability to characterize tumor was rated higher at 7 T compared with lower field MRI, P = 0.05. Confidence in visualizing normal gland was also higher using 7 T MRI, P = 0.036. The six hormone-secreting tumors had higher corrected T2 mean SI than non-secreting tumors (2.54 vs. − 0.38, P = 0.0196). Seven patients had preoperative hypopituitarism and had significantly greater stalk curvature angles than patients without hypopituitarism (71.7° vs. 36.55°, P = 0.027). Conclusion: Radiological characterization of pituitary adenomas and adjacent native pituitary tissue may benefit with the use of 7 T MRI. Corrected T2 SI of tumor may be a sensitive predictor of hormonal secretion and may be useful in the diagnostic work-up for pituitary adenoma. Summary statement: 7 T MRI may be valuable in identifying markers of endocrine function in patients with pituitary adenomas. Our results indicate that hormone-secreting tumors have higher T2-weighted SI and tumors associated with preoperative hypopituitarism have greater stalk curvature angles. [ABSTRACT FROM AUTHOR]