Perfusion-Weighted Imaging: The Use of a Novel Perfusion Scoring Criteria to Improve the Assessment of Brain Tumor Recurrence versus Treatment Effects.

INTRODUCTION: Imaging surveillance of contrast-enhancing lesions after the treatment of malignant brain tumors with radiation is plagued by an inability to reliably distinguish between tumor recurrence and treatment effects. Magnetic resonance perfusion-weighted imaging (PWI)-among other advanced brain tumor imaging modalities-is a useful adjunctive tool for distinguishing between these two entities but can be clinically unreliable, leading to the need for tissue sampling to confirm diagnosis. This may be partially because clinical PWI interpretation is non-standardized and no grading criteria are used for assessment, leading to interpretation discrepancies. This variance in the interpretation of PWI and its subsequent effect on the predictive value has not been studied. Our objective is to propose structured perfusion scoring criteria and determine their effect on the clinical value of PWI. METHODS: Patients treated at a single institution between 2012 and 2022 who had prior irradiated malignant brain tumors and subsequent progression of contrast-enhancing lesions determined by PWI were retrospectively studied from CTORE (CNS Tumor Outcomes Registry at Emory). PWI was given two separate qualitative scores (high, intermediate, or low perfusion). The first (control) was assigned by a neuroradiologist in the radiology report in the course of interpretation with no additional instruction. The second (experimental) was assigned by a neuroradiologist with additional experience in brain tumor interpretation using a novel perfusion scoring rubric. The perfusion assessments were divided into three categories, each directly corresponding to the pathology-reported classification of residual tumor content. The interpretation accuracy in predicting the true tumor percentage, our primary outcome, was assessed through Chi-squared analysis, and inter-rater reliability was assessed using Cohen's Kappa. RESULTS: Our 55-patient cohort had a mean age of 53.5 ± 12.2 years. The percentage agreement between the two scores was 57.4% (κ: 0.271). Upon conducting the Chi-squared analysis, we found an association with the experimental group reads (p-value: 0.014) but no association with the control group reads (p-value: 0.734) in predicting tumor recurrence versus treatment effects. CONCLUSIONS: With our study, we showed that having an objective perfusion scoring rubric aids in improved PWI interpretation. Although PWI is a powerful tool for CNS lesion diagnosis, methodological radiology evaluation greatly improves the accurate assessment and characterization of tumor recurrence versus treatment effects by all neuroradiologists. Further work should focus on standardizing and validating scoring rubrics for PWI evaluation in tumor patients to improve diagnostic accuracy.

Transcriptomics of intracranial aneurysms: current state and opportunities in flow diversion.

Over the last 2 decades, the field of transcriptomics has emerged as a major subdiscipline in biology. Transcriptomic techniques have been used by many groups over this time to better understand intracranial aneurysm development, rupture, and treatment. However, only a few studies have applied transcriptomics to understand the mechanisms behind flow diversion (FD) specifically, despite its increasing importance in the neurointerventional armamentarium. FD is an increasingly safe and effective treatment option for intracranial aneurysms. However, the clinical understanding and use of FD has far outpaced the understanding of the underlying mechanisms. To make FD more predictable, clinically efficacious, and safe, it is important to understand the biological mechanisms at play that lead to successful and unsuccessful FD. In this review, the authors focus on the current understanding of FD biology, the recent advances in transcriptomics, and what future studies could be performed to deepen the understanding of FD. They propose the new concept of the FD microenvironment to be studied, which may unlock a deeper biological understanding. This review provides the background for prospective studies into the development of targeted aneurysm therapy, whether by modified devices or by medical adjuncts.

Dexamethasone and Statins in Patients Undergoing Primary Middle Meningeal Artery Embolization for Chronic Subdural Hematoma: A Propensity-Matched Study in the TriNetX Research Network.

OBJECTIVE: Middle meningeal artery embolization (MMAE) is an effective minimally invasive option for chronic subdural hematoma (cSDH). Dexamethasone and statins have been reported to improve the resolution of cSDH and reduce its recurrence. However, only 1 study has investigated the role of statins in patients treated with MMAE, and there is no such study on dexamethasone. Thus, we used the TriNetX research network to determine whether adding dexamethasone or statin along with primary MMAE is associated with a benefit in outcomes. METHODS: We queried all primary MMAE cases for cSDH between January 1st, 2012, and July 1st, 2022, in the TriNetX research network. We included patients greater than or equal to 18 years old and separated them regarding statin and dexamethasone use around the time of MMAE. Outcomes were evaluated within 6 months and 3 years after MMAE, and analyses were performed before and after propensity score matching. RESULTS: The study included 372 patients with chronic subdural hematoma who underwent MMAE and were on dexamethasone, 339 not on dexamethasone, 391 on statins, and 278 not on statins. After propensity score matching, the dexamethasone cohorts included 250 patients each and only headache remained more prevalent in the dexamethasone cohort at both 6 months (21.2% vs. 10.0%, P = 0.001) and 3 years (23.6% vs. 12.4%, P = 0.001). After propensity score matching, the statin cohorts included 150 patients each and no differences in outcomes were found at both 6 months and 3 months after MMAE. CONCLUSIONS: Patients treated with primary MMAE and were on dexamethasone or statins had no differences in mortality and functional/provider dependence compared to those who were not on dexamethasone or statins. Patients on dexamethasone had a higher prevalence of headaches.

Examining the Effect of ALK and EGFR Mutations on Survival Outcomes in Surgical Lung Brain Metastasis Patients.

In the context of the post-genomic era, where targeted oncological therapies like monoclonal antibodies (mAbs) and tyrosine-kinase inhibitors (TKIs) are gaining prominence, this study investigates whether these therapies can enhance survival for lung carcinoma patients with specific genetic mutations-EGFR-amplified and ALK-rearranged mutations. Prior to this study, no research series had explored how these mutations influence patient survival in cases of surgical lung brain metastases (BMs). Through a multi-site retrospective analysis, the study examined patients who underwent surgical resection for BM arising from primary lung cancer at Emory University Hospital from January 2012 to May 2022. The mutational statuses were determined from brain tissue biopsies, and survival analyses were conducted. Results from 95 patients (average age: 65.8 ± 10.6) showed that while 6.3% had anaplastic lymphoma kinase (ALK)-rearranged mutations and 20.0% had epidermal growth factor receptor (EGFR)-amplified mutations-with 9.5% receiving second-line therapies-these mutations did not significantly correlate with overall survival. Although the sample size of patients receiving targeted therapies was limited, the study highlighted improved overall survival and progression-free survival rates compared to earlier trials, suggesting advancements in systemic lung metastasis treatment. The study suggests that as more targeted therapies emerge, the prospects for increased overall survival and progression-free survival in lung brain metastasis patients will likely improve.

Large Language Model-Based Neurosurgical Evaluation Matrix: A Novel Scoring Criteria to Assess the Efficacy of ChatGPT as an Educational Tool for Neurosurgery Board Preparation.

INTRODUCTION: Technological advancements are reshaping medical education, with digital tools becoming essential in all levels of training. Amidst this transformation, the study explores the potential of ChatGPT, an artificial intelligence model by OpenAI, in enhancing neurosurgical board education. The focus extends beyond technology adoption to its effective utilization, with ChatGPT's proficiency evaluated against practice questions from the Primary Neurosurgery Written Board Exam. METHODS: Using the Congress of Neurologic Surgeons (CNS) Self-Assessment Neurosurgery (SANS) Exam Board Review Prep questions, we conducted 3 rounds of analysis with ChatGPT. We developed a novel ChatGPT Neurosurgical Evaluation Matrix (CNEM) to assess the output quality, accuracy, concordance, and clarity of ChatGPT's answers. RESULTS: ChatGPT achieved spot-on accuracy for 66.7% of prompted questions, 59.4% of unprompted questions, and 63.9% of unprompted questions with a leading phrase. Stratified by topic, accuracy ranged from 50.0% (Vascular) to 78.8% (Neuropathology). In comparison to SANS explanations, ChatGPT output was considered better in 19.1% of questions, equal in 51.6%, and worse in 29.3%. Concordance analysis showed that 95.5% of unprompted ChatGPT outputs and 97.4% of unprompted outputs with a leading phrase were aligned. CONCLUSIONS: Our study evaluated the performance of ChatGPT in neurosurgical board education by assessing its accuracy, clarity, and concordance. The findings highlight the potential and challenges of integrating AI technologies like ChatGPT into medical and neurosurgical board education. Further research is needed to refine these tools and optimize their performance for enhanced medical education and patient care.