Augmented 360° Three-Dimensional Virtual Reality for Enhanced Student Training and Education in Neurosurgery.

OBJECTIVE: This prospective study assesses the acceptance and usefulness of augmented 360° virtual reality (VR) videos for early student education and preparation in the field of neurosurgery. METHODS: Thirty-five third-year medical students participated. Augmented 360° VR videos depicting three neurosurgical procedures (lumbar discectomy, brain metastasis resection, clipping of an aneurysm) were presented during elective seminars. Multiple questionnaires were employed to evaluate conceptual and technical aspects of the videos. The analysis utilized ordinal logistic regression to identify crucial factors contributing to the learning experience of the videos. RESULTS: The videos were consistently rated as good to very good in quality, providing detailed demonstrations of intraoperative anatomy and surgical workflow. Students found the videos highly useful for their learning and preparation for surgical placements, and they strongly supported the establishment of a VR lounge for additional self-directed learning. Notably, 81% reported an increased interest in neurosurgery, and 47% acknowledged the potential influence of the videos on their future choice of specialization. Factors associated with a positive impact on students' interest and learning experience included high technical quality and comprehensive explanations of the surgical steps. CONCLUSIONS: This study demonstrated the high acceptance of augmented 360° VR videos as a valuable tool for early student education in neurosurgery. While hands-on training remains indispensable, these videos promote conceptual knowledge, ignite interest in neurosurgery, and provide a much-needed orientation within the operating room. The incorporation of detailed explanations throughout the surgeries with augmentation using superimposed elements, offers distinct advantages over simply observing live surgeries.

Corrigendum: What if: a retrospective reconstruction of resection cavity stereotactic radiosurgery to mimic neoadjuvant stereotactic radiosurgery.

[This corrects the article DOI: 10.3389/fonc.2023.1056330.].

The Brain Tumor Segmentation (BraTS-METS) Challenge 2023: Brain Metastasis Segmentation on Pre-treatment MRI.

Clinical monitoring of metastatic disease to the brain can be a laborious and timeconsuming process, especially in cases involving multiple metastases when the assessment is performed manually. The Response Assessment in Neuro-Oncology Brain Metastases (RANO-BM) guideline, which utilizes the unidimensional longest diameter, is commonly used in clinical and research settings to evaluate response to therapy in patients with brain metastases. However, accurate volumetric assessment of the lesion and surrounding peri-lesional edema holds significant importance in clinical decision-making and can greatly enhance outcome prediction. The unique challenge in performing segmentations of brain metastases lies in their common occurrence as small lesions. Detection and segmentation of lesions that are smaller than 10 mm in size has not demonstrated high accuracy in prior publications. The brain metastases challenge sets itself apart from previously conducted MICCAI challenges on glioma segmentation due to the significant variability in lesion size. Unlike gliomas, which tend to be larger on presentation scans, brain metastases exhibit a wide range of sizes and tend to include small lesions. We hope that the BraTS-METS dataset and challenge will advance the field of automated brain metastasis detection and segmentation.

What if: A retrospective reconstruction of resection cavity stereotactic radiosurgery to mimic neoadjuvant stereotactic radiosurgery.

Introduction: Neoadjuvant stereotactic radiosurgery (NaSRS) of brain metastases has gained importance, but it is not routinely performed. While awaiting the results of prospective studies, we aimed to analyze the changes in the volume of brain metastases irradiated pre- and postoperatively and the resulting dosimetric effects on normal brain tissue (NBT). Methods: We identified patients treated with SRS at our institution to compare hypothetical preoperative gross tumor and planning target volumes (pre-GTV and pre-PTV) with original postoperative resection cavity volumes (post-GTV and post-PTV) as well as with a standardized-hypothetical PTV with 2.0 mm margin. We used Pearson correlation to assess the association between the GTV and PTV changes with the pre-GTV. A multiple linear regression analysis was established to predict the GTV change. Hypothetical planning for the selected cases was created to assess the volume effect on the NBT exposure. We performed a literature review on NaSRS and searched for ongoing prospective trials. Results: We included 30 patients in the analysis. The pre-/post-GTV and pre-/post-PTV did not differ significantly. We observed a negative correlation between pre-GTV and GTV-change, which was also a predictor of volume change in the regression analysis, in terms of a larger volume change for a smaller pre-GTV. In total, 62.5% of cases with an enlargement greater than 5.0 cm3 were smaller tumors (pre-GTV < 15.0 cm3), whereas larger tumors greater than 25.0 cm3 showed only a decrease in post-GTV. Hypothetical planning for the selected cases to evaluate the volume effect resulted in a median NBT exposure of only 67.6% (range: 33.2-84.5%) relative to the dose received by the NBT in the postoperative SRS setting. Nine published studies and twenty ongoing studies are listed as an overview. Conclusion: Patients with smaller brain metastases may have a higher risk of volume increase when irradiated postoperatively. Target volume delineation is of great importance because the PTV directly affects the exposure of NBT, but it is a challenge when contouring resection cavities. Further studies should identify patients at risk of relevant volume increase to be preferably treated with NaSRS in routine practice. Ongoing clinical trials will evaluate additional benefits of NaSRS.

Personalized surgical informed consent with stereoscopic visualization in neurosurgery-real benefit for the patient or unnecessary gimmick?

BACKGROUND: Informed consent of the patient prior to surgical procedures is obligatory. A good and informative communication improves patients' understanding and confidence, thus may strengthen the patient-doctor relationship. The aim of our study was to investigate the usefulness of additional stereoscopic visualization of patient-specific imaging during informed consent conversation. METHODS: Patients scheduled for a brain tumor surgery were screened for this study prospectively. The primary exclusion criteria were cognitive or visual impairments. The participants were randomized into two groups. The first group underwent a conventional surgical informed consent performed by a neurosurgeon including a demonstration of the individual MRI on a 2D computer screen. The second group received an additional stereoscopic visualization of the same imaging to explain the pathology more in-depth. The patients were then asked to fill in a questionnaire after each part. This questionnaire was designed to assess the potential information gained from the patients with details on the anatomical location of the tumor as well as the surgical procedure and possible complications. Patients' subjective impression about the informed consent was assessed using a 5-point Likert scale. RESULTS: A total of 27 patients were included in this study. After additional stereoscopic visualization, no significant increase in patient understanding was found for either objective criteria or subjective assessment. Participants' anxiety was not increased by stereoscopic visualization. Overall, patients perceived stereoscopic imaging as helpful from a subjective perspective. Confidence in the department was high in both groups. CONCLUSION: Stereoscopic visualization of MRI images within informed consent conversation did not improve the objective understanding of the patients in our series. Although no objective anatomical knowledge gain was noted in this series, patients felt that the addition of stereoscopic visualization improved their overall understanding. It therefore potentially increases patient confidence in treatment decisions.