External Ventricular Drain Training in Medical Students Improves Procedural Accuracy and Attitudes Toward Virtual Reality.

OBJECTIVE: Neurosurgery residents face a learning curve at the beginning of residency. Virtual reality (VR) training may alleviate challenges through an accessible, reusable, anatomical model. METHODS: Medical students performed external ventricular drain placements in VR to characterize the learning curve from novice to proficient. Distance from catheter to foramen of Monro and location with respect to ventricle were recorded. Changes in attitudes toward VR were assessed. Neurosurgery residents performed external ventricular drain placements to validate proficiency benchmarks. Resident and student impressions of the VR model were compared. RESULTS: Twenty-one students with no neurosurgical experience and 8 neurosurgery residents participated. Student performance improved significantly from trial 1 to 3 (15 mm [12.1-20.70] vs. 9.7 [5.8-15.3], P = 0.02). Student attitudes regarding VR utility improved significantly posttrial. The distance to foramen of Monro was significantly shorter for residents than for students in trial 1 (9.05 [8.25-10.73] vs. 15 [12.1-20.70], P = 0.007) and trial 2 (7.45 [6.43-8.3] vs. 19.5 [10.9-27.6], P = 0.002). By trial 3 there was no significant difference (10.1 [8.63-10.95 vs. 9.7 [5.8-15.3], P = 0.62). Residents and students provided similarly positive feedback for VR in resident curricula, patient consent, preoperative practice and planning. Residents provided more neutral-to-negative feedback regarding skill development, model fidelity, instrument movement, and haptic feedback. CONCLUSIONS: Students showed significant improvement in procedural efficacy which may simulate resident experiential learning. Improvements in fidelity are needed before VR can become a preferred training technique in neurosurgery.

Intraoperative use of heads-up display in skull base surgery.

In this video, the authors highlight the applications of virtual reality and heads-up display in skull base surgery by presenting the case of a 45-year-old woman with an incidental large clinoid meningioma extending into the posterior fossa. The patient underwent preoperative endovascular tumor embolization to facilitate tumor resection and reduce blood loss, followed by a right pterional craniotomy. The use of intraoperative Doppler, intraoperative neurophysiological monitoring, and endoscope-assisted microsurgery is also featured. A subtotal resection was planned given tumor encasement of the posterior communicating and anterior choroidal arteries. No new neurological deficits were noted after the surgical procedure. The video can be found here: https://stream.cadmore.media/r10.3171/2021.10.FOCVID21177.

Augmented reality-assisted microsurgical resection of brain arteriovenous malformations: illustrative case.

BACKGROUND: Arteriovenous malformations (AVMs) of the brain are vessel conglomerates of feeding arteries and draining veins that carry a risk of spontaneous and intraoperative rupture. Augmented reality (AR)-assisted neuronavigation permits continuous, real-time, updated visualization of navigation information through a heads-up display, thereby potentially improving the safety of surgical resection of AVMs. OBSERVATIONS: The authors report a case of a 37-year-old female presenting with a 2-year history of recurrent falls due to intermittent right-sided weakness and increasing clumsiness in the right upper extremity. Magnetic resonance imaging, magnetic resonance angiography, and cerebral angiography of the brain revealed a left parietal Spetzler-Martin grade III AVM. After endovascular embolization of the AVM, microsurgical resection using an AR-assisted neuronavigation system was performed. Postoperative angiography confirmed complete obliteration of arteriovenous shunting. The postsurgical course was unremarkable, and the patient remains in excellent health. LESSONS: Our case describes the operative setup and intraoperative employment of AR-assisted neuronavigation for AVM resection. Application of this technology may improve workflow and enhance patient safety.

A Virtual-Reality, 360-Degree Fly-Through of an Arteriovenous Malformation Resection: 2-Dimensional Operative Video.

The application of navigation integrated virtual reality (VR) in neurosurgery is an emerging paradigm that may offer improved situational awareness for the surgeon. Here, we present a case of a complex arteriovenous malformation (AVM) with complex venous drainage and observe how VR impacted structural delineation during approach, resection, and overall strategic planning. The patient was a 30-yr-old female with no past medical history who presented with headaches and a generalized tonic clonic seizure. Workup included computed tomography, computed tomography angiography, magnetic resonance imaging, magnetic resonance angiography, and magnetic resonance venography; a high flow right frontal AVM was found. The AVM was safely resected using navigation integrated with VR; careful arterial devascularization preceded resection of the draining veins and then the AVM nidus. Postoperative scans confirmed complete resection of the AVM. This case outlines the application of a current state-of-the-art VR platform to assist the craniotomy for resection of an AVM.

Robotic surgical rehearsal on patient-specific 3D-printed skull models for stereoelectroencephalography (SEEG).

PURPOSE: Medically refractory epilepsy patients commonly require surgical alternatives for diagnosis and treatment. Stereoelectroencephalography (SEEG) is a useful diagnostic procedure in seizure focus elucidation. Modern techniques involve the use of robotics and neuronavigation for SEEG. A steep learning curve combined with multiple complex technologies employed during the case makes this procedure a perfect candidate for surgical rehearsal. This paper tests the feasibility of the use of patient-specific 3D-printed model for surgical rehearsal of robotic SEEG. METHODS: A 3D-printed model was created using the patient's cranial computed tomography and computed tomography angiography radiological imaging. A rehearsal in an operating room (OR) prior to the actual procedure date was used for surgical planning of SEEG electrodes, education of the residents and fellows as well as training of the support staff. Attention was paid to assure precise recreation of the surgical procedure. RESULTS: The patient-specific 3D-printed model tolerated each step of the procedure from facial registration, to drilling, bolt insertion and lead placement. Accuracy of the designed trajectory to the electrode final position was visually confirmed at the end of procedure. Important modification to the plan of eventual surgery improved the efficiency of the real operation. CONCLUSION: For surgical planning, education and training purposes in robotic SEEG, 3D-printed models may be utilized as a realistic anatomy tool. Potential applications of this technique include trajectory feasibility evaluation, patient positioning optimization, increasing OR efficiency, as well as neurosurgical education and patient counseling.

Navigation-Linked Heads-Up Display in Intracranial Surgery: Early Experience.

BACKGROUND: The use of intraoperative navigation during microscope cases can be limited when attention needs to be divided between the operative field and the navigation screens. Heads-up display (HUD), also referred to as augmented reality, permits visualization of navigation information during surgery workflow. OBJECTIVE: To detail our initial experience with HUD. METHODS: We retrospectively reviewed patients who underwent HUD-assisted surgery from April 2016 through April 2017. All lesions were assessed for accuracy and those from the latter half of the study were assessed for utility. RESULTS: Seventy-nine patients with 84 pathologies were included. Pathologies included aneurysms (14), arteriovenous malformations (6), cavernous malformations (5), intracranial stenosis (3), meningiomas (27), metastasis (4), craniopharygniomas (4), gliomas (4), schwannomas (3), epidermoid/dermoids (3), pituitary adenomas (2) hemangioblastoma (2), choroid plexus papilloma (1), lymphoma (1), osteoblastoma (1), clival chordoma (1), cerebrospinal fluid leak (1), abscess (1), and a cerebellopontine angle Teflon granuloma (1). Fifty-nine lesions were deep and 25 were superficial. Structures identified included the lesion (81), vessels (48), and nerves/brain tissue (31). Accuracy was deemed excellent (71.4%), good (20.2%), or poor (8.3%). Deep lesions were less likely to have excellent accuracy (P = .029). HUD was used during bed/head positioning (50.0%), skin incision (17.3%), craniotomy (23.1%), dural opening (26.9%), corticectomy (13.5%), arachnoid opening (36.5%), and intracranial drilling (13.5%). HUD was deactivated at some point during the surgery in 59.6% of cases. There were no complications related to HUD use. CONCLUSION: HUD can be safely used for a wide variety of vascular and oncologic intracranial pathologies and can be utilized during multiple stages of surgery.