Randomized study comparing 3D virtual reality and conventional 2D on-screen teaching of cerebrovascular anatomy

OBJECTIVE Performing aneurysmal clipping requires years of training to successfully understand the 3D neurovascular anatomy. This training has traditionally been obtained by learning through observation. Currently, with fewer operative aneurysm clippings, stricter work-hour regulations, and increased patient safety concerns, novel teaching methods are required for young neurosurgeons. Virtual-reality (VR) models offer the opportunity to either train a specific surgical skill or prepare for an individual surgery. With this study, the authors aimed to compare the spatial orientation between traditional 2D images and 3D VR models in neurosurgical residents or medical students. METHODS Residents and students were each randomly assigned to describe 4 aneurysm cases, which could be either 2D images or 3D VR models. The time to aneurysm detection as well as a spatial anatomical description was assessed via an online questionnaire and compared between the groups. The aneurysm cases were 10 selected patient cases treated at the authors’ institution. RESULTS Overall, the time to aneurysm detection was shorter in the 3D VR model compared to 2D images, with a trend toward statistical significance (25.77 ± 37.26 vs 45.70 ± 51.94 seconds, p = 0.052). No significant difference was observed for residents (3D VR 24.47 ± 40.16 vs 2D 33.52 ± 56.06 seconds, p = 0.564), while in students a significantly shorter time to aneurysm detection was measured using 3D VR models (26.95 ± 35.39 vs 59.16 ± 44.60 seconds, p = 0.015). No significant differences between the modalities for anatomical and descriptive spatial mistakes were observed. Most participants (90%) preferred the 3D VR models for aneurysm detection and description, and only 1 participant (5%) described VR-related side effects such as dizziness or nausea. CONCLUSIONS VR platforms facilitate aneurysm recognition and understanding of its spatial anatomy, which could make them the preferred method compared to 2D images in the years to come.

Transcavernous Approach for Microsurgical Clipping of Ruptured Right Superior Cerebellar Artery Aneurysm with Cadaveric Stepwise Video Illustration

Superior cerebellar artery (SCA) aneurysms are rare. The management options are not well defined. There is increasing role of endovascular treatment for all aneurysms, especially for aneurysms of the posterior circulation. However in some situations (wide base, dysmorphic features) coiling is not feasible. The surgical management of these aneurysms has its own distinct complexity and requires careful planning. The classic pterional or subtemporal approaches had its own limitation in proper visualization of the neurovascular anatomy.In this video, we describe the technical nuances of transcavernous sinus approach for microsurgical clipping SCA and A-comm aneurysms. We present the case of a 67-year-old RHF who presented with ruptured right-sided SCA aneurysm. She complained of Headache, confusion, and double vision. On physical examination, she had no focal deficits and was Hunt and Hess grade 3. A brain computed tomography (CT) scan revealed a subarachnoid hemorrhage Fisher's grade 4. A brain CT angiography (CTA) demonstrated an aneurysm at the origin of right SCA. The patient had failed attempt of endovascular coiling and she underwent microsurgical clipping.Stepwise demonstration of the approach with cadaveric anatomical dissection is illustrated. The technique presented here allows for safe clipping of the aneurysm through the cavernous sinus. The approach allows for good exposure of the aneurysm and the surrounding structures. Care is taken to visualize the perforators to avoid any devastating brain stem infarction during the clipping.The transcavernous sinus is a robust approach with good visualization of the neurovascular structures allowing safe aneurysm clipping in this location.The link to the video can be found at: https://youtu.be/oE-HyDASiKM.

Pancreas Optical Clearing and 3-D Microscopy in Health and Diabetes

Although first described over a hundred years ago, tissue optical clearing is undergoing renewed interest due to numerous advances in optical clearing methods, microscopy systems, and three-dimensional (3-D) image analysis programs. These advances are advantageous for intact mouse tissues or pieces of human tissues because samples sized several millimeters can be studied. Optical clearing methods are particularly useful for studies of the neuroanatomy of the central and peripheral nervous systems and tissue vasculature or lymphatic system. Using examples from solvent- and aqueous-based optical clearing methods, the mouse and human pancreatic structures and networks will be reviewed in 3-D for neuro-insular complexes, parasympathetic ganglia, and adipocyte infiltration as well as lymphatics in diabetes. Optical clearing with multiplex immunofluorescence microscopy provides new opportunities to examine the role of the nervous and circulatory systems in pancreatic and islet functions by defining their neurovascular anatomy in health and diabetes.

Description and Validation of an Innovative and Effective Hand-Shaped Suture-Training Model for Medical Students

During medical education, medical students are often frustrated by difficulties in translating theoretical anatomical knowledge and basic surgical skills (suturing, tissue and instrument handling, and local anesthetic administration) into practice. A common etiological factor for this difficulty, among others, is lack of a low-cost and easy-to-assemble low fidelity suturing model. The purpose of this study is the demonstration of a validated, practical, inexpensive, hand-shaped anatomy training model. It is addressed to medical students and graduates that wish to get acquainted with neurovascular anatomy of the hand and improve their basic surgical skills. The model requires only two latex gloves, cotton, and two different color markers per trainee to draw the course of large nerve and vessels. Construction requires less than 15 minutes. For validation, 80 students participated as volunteers in the demonstration course. They evaluated course usefulness and their own confidence after the course. According to the 5-point Likert scale, the participants’ confidence increased in a statistically significant way (p < 0.05). All participants (100%) stated that their skills were “significantly improved” in terms of instrument handling, anatomy studying, performing digital anesthesia, and suturing technique. Overall experience was rated as “satisfactory” or above. The proposed model enables safe gentle soft-tissue handling, and it resembles a realistic human tissue. Low cost, availability, and fast construction are the most important characteristics, making this validated training model appropriate for acquiring fundamental local anesthesia, respect for hand neurovascular anatomy, and suturing skills.

Orbital Anatomy: Anatomical Relationships of Surrounding Structures

Advances in skull base and orbital surgery have led to an increased need to understand the anatomy of the orbit and surrounding structures to safely perform surgeries in this area. The purpose of this article is to review the surrounding anatomy of the orbit from a practical and operative point of view. We describe the orbit from an inferomedial endoscopic endonasal perspective (focusing on its inferior relationship with the maxillary sinus and related structures and its medial relationship with the ethmoid bone), from a posterior and superolateral intracranial perspective (describing the anatomy of the superior orbital fissure, optic canal, inferior orbital fissure, cavernous sinus, orbitofrontal cortex, and surrounding dura) and from an anterior perspective (focusing on the muscles, connective tissue, lateral and medial canthus, and relevant neurovascular anatomy). A deep knowledge of the critical neurovascular and osseous structures surrounding the orbit is necessary for adequately choosing and performing the most favorable orbital approach in every case.