Virtual reality surgical planning for endoscopic endonasal approaches to the craniovertebral junction.

PURPOSE: To demonstrate the utility of virtual reality (VR) for preoperative surgical planning of endoscopic endonasal craniovertebral junction (CVJ) surgery. MATERIALS AND METHODS: Five patients who had undergone endoscopic endonasal surgery of the craniovertebral junction with preoperative virtual reality surgical planning were identified and described. RESULTS: The anterior approach to the CVJ has been traditionally accomplished transorally. However, recently the transnasal endoscopic approach to this location has been described. Multiple anatomical studies have been conducted using the nasopalatine, nasoaxial, and rhinopalatine lines (NPL, NAxL, RPL) in an attempt to preoperatively delineate the inferior limits of endoscopic dissection. The use of advanced surgical simulation using immersive virtual reality is an innovative approach for analyzing CVJ anatomy and developing a surgical plan. VR simulation through the use of interactive and highly accurate patient specific models allows for the creation of three-dimensional (3D) digital reconstructions via the fusion of CT and MRI studies. Incorporation of simulation technology has been shown to increase surgeon proficiency while simultaneously decreasing complication rates. The described case series demonstrates the novel utility of VR planning for designing the endoscopic surgical approach to the CVJ. CONCLUSIONS: VR technology allows for the creation of anatomically accurate 3D models that can be used for preoperative planning of endoscopic endonasal surgery. Such models help in the development of safe surgical plans by predicting inferior and lateral planes of dissection and assisting in the identification of critical structures.

Use of Mixed Reality Visualization in Endoscopic Endonasal Skull Base Surgery.

BACKGROUND: Neuronavigation systems assist with spatial orientation during endoscopic transnasal skull base surgery, but they require a correlation of 3-dimensional (3D) views with 2-dimensional (2D) radiology studies. OBJECTIVE: To outline an initial experience with a novel technology platform that provides intraoperative navigation using 3D reconstructions of patient anatomy for endoscopic surgery. METHODS: A retrospective study of endoscopic anterior skull base and complex paranasal procedures was performed. Data from preoperative computed tomography and magnetic resonance imaging scans were fused to create 3D digital models of patient anatomy. Using the technology developed by Surgical Theater (Mayfield Village, Ohio), these reconstructions were designed to highlight particular anatomic regions of interest. The models were studied to guide the surgical approach and anticipate critical structures.The reconstructions were linked with the navigational technology created by Brainlab (Munich, Germany) during endoscopic surgery. A dynamic image of the reconstruction was displayed alongside a matching endoscopic camera view. These 2 views could be overlaid to provide an immersive, mixed reality image of the patient's anatomy. RESULTS: A total of 134 cases were performed. The pathologies included tumors of the anterior skull base or sinonasal cavity, inflammatory sinus disease, and cerebrospinal fluid leaks. Specific anatomic structures, such as the internal carotid arteries and optic nerves, were chosen for enhancement. Surgeons felt that the technology helped to guide the extent of bony dissection and to identify critical structures. CONCLUSION: We describe the first clinical series of complex skull base pathologies treated using a novel mixed reality platform.

Intracranial Meningioma Surgery: Value-Based Care Determinants in New York State, 1995-2015.

OBJECTIVE: Intracranial meningiomas are the most commonly diagnosed brain tumor in the United States. With increasing incidence, efficient allocation of limited health care resources is a critical component of emerging value-based models of care. The purpose of this study was to evaluate the effect of patient and hospital variables on metrics of value-based care. METHODS: The Statewide Planning and Research Cooperative System database was queried for records of patients undergoing intracranial meningioma surgery in New York State from 1995 to 2015. Multivariate logistic regression was used to investigate the effect of hospital volume and patient demographics on 30-day readmissions, 30-day mortality, prolonged length of stay (pLOS), and excess hospital charges. RESULTS: Among the 14,239 patients included, 10,252 (72%) cases were performed at high-volume centers (HVC) (>75th percentile). HVC were associated with lower rates of readmissions, mortality, and pLOS, but higher hospital charges. In the multivariate analysis, HVC had reduced odds of pLOS (odds ratio, 0.56; P < 0.0001) and 30-day mortality (odds ratio, 0.39; P < 0.0001). Patient variables associated with adverse outcomes in the multivariate model included advanced age, male gender, higher Charlson Comorbidity Index, lower socioeconomic status (low income, Medicaid, and Medicare insurance), black race, and Hispanic ethnicity. These populations were more likely to undergo treatment at lower-volume centers. CONCLUSIONS: This statewide population analysis of readmissions, mortality, length of stay, and hospital charges after intracranial meningioma surgery identified patient predictors of adverse outcomes. These determinants may be used by hospitals to develop improved systems of care in at-risk populations.

Immersive virtual reality as a teaching tool for neuroanatomy.

BACKGROUND: Three-dimensional (3D) computer modeling and interactive virtual reality (VR) simulation are validated teaching techniques used throughout medical disciplines. Little objective data exists supporting its use in teaching clinical anatomy. Learner motivation is thought to limit the rate of utilization of such novel technologies. The purpose of this study is to evaluate the effectiveness, satisfaction, and motivation associated with immersive VR simulation in teaching medical students neuroanatomy. METHODS: Images of normal cerebral anatomy were reconstructed from human Digital Imaging and Communications in Medicine (DICOM) computed tomography (CT) imaging and magnetic resonance imaging (MRI) into 3D VR formats compatible with the Oculus Rift VR System, a head-mounted display with tracking capabilities allowing for an immersive VR experience. The ventricular system and cerebral vasculature were highlighted and labeled to create a focused interactive model. We conducted a randomized controlled study with 66 medical students (33 in both the control and experimental groups). Pertinent neuroanatomical structures were studied using either online textbooks or the VR interactive model, respectively. We then evaluated the students' anatomy knowledge, educational experience, and motivation (using the Instructional Materials Motivation Survey [IMMS], a previously validated assessment). RESULTS: There was no significant difference in anatomy knowledge between the 2 groups on preintervention, postintervention, or retention quizzes. The VR group found the learning experience to be significantly more engaging, enjoyable, and useful (all p < 0.01) and scored significantly higher on the motivation assessment (p < 0.01). CONCLUSION: Immersive VR educational tools awarded a more positive learner experience and enhanced student motivation. However, the technology was equally as effective as the traditional text books in teaching neuroanatomy.