Citations

Abstract Cadaveric dissections, which are considered the most realistic model to study neuroanatomy, are expensive and not readily available in all centers. Given the surge of technological advances, incorporation of three‐dimensional (3D) scanning technologies and 3D models has gained popularity, both in the educational and clinical settings. We present our institutional experience in creating high‐fidelity neuroanatomical 3D models using three 3D scanning techniques: structured light 3D scanning, “manual” photogrammetry with a single DSLR camera, and “automatic” photogrammetry using a scanner equipped with five vertically arranged DSLR cameras and an automatic turntable within a square box. A survey study was conducted with 20 neurosurgical residents to assess the quality of the three resulting 3D models. In the study, “manual” photogrammetry was determined to be the most cost‐effective technique, while “automatic” photogrammetry was the most time‐effective and user‐friendly technique. The best visual quality was obtained using “manual” photogrammetry, as determined from survey results of 20 neurosurgical residents. While structured light 3D scanning had the lowest quality of resolution of the texture map, this technique was the most accurate to use for determining measurements, with a fixed accuracy of 0.05 mm. Overall, “manual” photogrammetry can allow for the most detailed 3D models and is the most cost‐effective strategy, while structured light 3D scanning is most suitable for obtaining clinically relevant measurements given the high degree of structural accuracy. Alternatively, “automatic” photogrammetry can serve as a hybrid between obtaining relatively high‐quality models in a time‐effective and user‐friendly manner.

ABSTRACT Objective There is limited consensus on endoscopic skull base surgery (ESBS) reconstruction principles. This study aims to generate comprehensive themes regarding ESBS reconstruction by pooling the experiences of ESBS experts, with comparison to a literature review of current published evidence. Methods Structured qualitative interviews of ESBS experts regarding postoperative management and reconstruction of various defect locations were conducted. Results A total of 68 experts comprising 40 academic teams across 13 countries with an average of 18 years of ESBS experience were included. We propose 10 stepwise algorithms for common skull base reconstruction scenarios based on these expert interviews. When available, the nasoseptal flap is used for all high_flow cerebrospinal leak defects. Multilayered reconstruction is favored at all anatomical subsites with increasing number of layers for increasing defect size and complexity. Heterogeneity exists in terms of inlay technique and materials, free grafting versus various pedicled flap options for low‐flow defects or in the absence of a nasal septum, nasal packing, tissue sealant, lumbar drain use, and postoperative management. Commonalities and discrepancies between experts were summarized. Conclusion Skull base reconstruction and post‐ESBS management is highly complex with a wide variety of practice patterns and expert strategies. Further research of higher quality evidence is warranted to identify optimal management patterns, though the current work aims to inform surgeons on these controversial areas by drawing from numerous experiences.

OBJECTIVE In this study, the authors aimed to establish a supervised machine learning (ML) model based on multiple tree-based algorithms to predict long-term biochemical outcomes and intervention-free survival (IFS) after endonasal transsphenoidal surgery (ETS) in patients with Cushing’s disease (CD). METHODS The medical records of patients who underwent ETS for CD between 2013 and 2023 were reviewed. Data were collected on the patient’s baseline characteristics, intervention details, histopathology, surgical outcomes, and postoperative endocrine functions. The study’s primary outcome was IFS, and the therapeutic outcomes were labeled as "under control" or "treatment failure," depending on whether additional therapeutic interventions after primary ETS were required. The decision tree and random forest classifiers were trained and tested to predict long-term IFS based on unseen data, using an 80/20 cohort split. RESULTS Data from 150 patients, with a median follow-up period of 56 months, were extracted. In the cohort, 42 (28%) patients required additional intervention for persistent or recurrent CD. Consequently, the IFS rates following ETS alone were 83% at 3 years and 78% at 5 years. Multivariable Cox proportional hazards analysis demonstrated that a smaller tumor diameter that could be detected by MRI (hazard ratio 0.95, 95% CI 0.90–0.99; p = 0.047) was significantly associated with greater IFS. However, the lack of tumor detection on MRI was a poor predictor. The ML-based model using a decision tree model displayed 91% accuracy (95% CI 0.70–0.94, sensitivity 87.0%, specificity 89.0%) in predicting IFS in the unseen test dataset. Random forest analysis revealed that tumor size (mean minimal depth 1.67), Knosp grade (1.75), patient age (1.80), and BMI (1.99) were the four most significant predictors of long-term IFS. CONCLUSIONS The ML algorithm could predict long-term postoperative endocrinological remission in CD with high accuracy, indicating that prognosis may vary not only with previously reported factors such as tumor size, Knosp grade, gross-total resection, and patient age but also with BMI. The decision tree flowchart could potentially stratify patients with CD before ETS, allowing for the selection of personalized treatment options and thereby assisting in determining treatment plans for these patients. This ML model may lead to a deeper understanding of the complex mechanisms of CD by uncovering patterns embedded within the data.

BACKGROUND AND OBJECTIVES: Schwannomas are benign, slow-growing peripheral nerve sheath tumors. Approximately 8% of intracranial schwannomas originate from the trigeminal nerve. No consensus exists regarding superiority of outcomes after resection vs stereotactic radiosurgery (SRS) in the treatment of trigeminal schwannomas (TS). The aim of this study was to compare the efficacy and outcomes of resection vs SRS for TS management. METHODS: Embase, PubMed, and SCOPUS databases were queried from the date of inception to July 2023 for primary data reporting TS treatment outcomes after SRS or resection. Risk of bias was reported under Newcastle-Ottawa Scale. RESULTS: Overall, 29 retrospective observational studies comprising 949 patients were included in the analysis. A total of 13 studies (n = 589) reported outcomes after SRS, and 16 studies (n = 360) reported outcomes after surgical resection, and 182 patients in the SRS group had previous resection. To ensure statistical validity of comparing the cohorts, 3 checkpoints were assessed: the median age (SRS: 48 vs surgery: 40 years old, P < .01), tumor volume (5.2 vs 8.9 cm 3 , P = .06), and median follow-up (53.9 vs 48.5 months, P = .59), which reflected the choice of treatment. Compared with surgical resection, the SRS group demonstrated significantly higher rates of facial hypesthesia improvement (44% vs 12%, P < .01) and lower rates of new onset (4% vs 15%, P = .051) at last follow-up. Facial pain was less likely to improve (58% vs 81%, P = .024) after SRS compared with surgery. However, worsened (5% vs 1%, P = .71) and new facial pain (2% vs 1%, P = .55) were comparable between cohorts. CONCLUSION: SRS seems to offer improvement in rates of hypesthesia and trigeminal motor deficits compared with surgical resection for TS. However, facial pain improvement was more favorable after surgery. These findings highlight the importance of individualized treatment decisions based on patient characteristics, tumor profile, and pretreatment symptoms.

BACKGROUND AND OBJECTIVES: The lateral transorbital approach (LTOA) has gained increased recognition, but there is still a paucity of data on its effectiveness and advantages compared with the LTOA with lateral orbitotomy, herein denoted as the lateral orbital wall approach (LOWA). The aim of this study was to provide an anatomical reappraisal and the authors' clinical experience to compare the 2 approaches to the orbit and middle cranial fossa (MCF). METHODS: Eight latex-injected cadaveric specimens were used to perform LTOA and LOWA. The operative depth of each approach to key anatomical landmarks was measured. Fifty high-resolution computed tomography studies were reviewed to calculate the operative angles. We reviewed 40 consecutive cases treated with LTOA and LOWA at our institution. RESULTS: Compared with the LTOA, the LOWA provided shorter operative depths to the optic foramen ( P < .05), foramen ovale ( P < .05), and to the junction eyeball-cranial nerve II ( P = .13). It also offered better access to the anterior aspect of the orbit with less orbital content retraction. The LTOA and LOWA provided different operative angles to key anatomical landmarks in the orbit and MCF ( P < .05). In our chart review, 31 patients underwent the LTOA, whereas 9 underwent the LOWA to treat orbital and MCF lesions. Patients undergoing LOWA experienced postoperative complications related to periorbital nerves, such as frontalis palsy (n = 1) and supraorbital neuralgia (n = 1). Patients undergoing LTOA were more prone to complications associated with intraorbital manipulation (n = 4), including diplopia and ptosis. CONCLUSION: Our data suggest that the LTOA can be an effective surgical strategy for addressing orbital apex and MCF lesions. Although the LOWA provides access to the aforementioned areas, it may be more suitable for anterior orbital lesions that require direct access with wider entry exposure and extensive orbital content manipulation.