Individualized photorealistic environments for exposure therapy can be readily created using 360° panoramic movies recorded with a consumer-quality camcorder. These panoramic movies are presented on a head-mounted display equipped with a position-tracking device to enable looking around the virtual environment. To demonstrate the treatment efficacy of this individualized virtual reality exposure therapy using 360° panoramic movies, we report a case study of the treatment of a 13-year-old male with severe fear and avoidance of heights. We made panoramic movies of situations where he reported fear, and presented them on a head-mounted display. A total of 8 exposure sessions were conducted over a period of 9 weeks. All his self-report measures of fear and avoidance of heights decreased as the treatment progressed, and were maintained at a 7-month follow-up.

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BACKGROUND: Neurosurgeons must perform surgeries with great care to avoid adverse sequelae. Before surgery, they must devise a precise surgical plan for removing brain stem tumors, and this plan should incorporate a variety of medical images based upon different imaging modalities. However, current medical imaging modalities cannot visualize cranial nerve tracts displaced by the tumors. Surgeons must thus rely upon their knowledge and experience to estimate the topology of displaced cranial nerve tracts. METHODS: A 3D visualizing system for estimating cranial nerve tracts displaced by brain stem tumors (CranialNvSim) was developed using a software development platform called UNITY (Unity Technologies, San Francisco, CA), and this was used to perform functional evaluations. A software application named AMIRA (FEI, Hillsboro, OR) was used to derive 3D models comprising brain stems, cranial arteries and brain stem tumors. The shapes of the cranial nerves were derived by a software application called Maya (Autodesk, San Rafael, CA) based upon a standard anatomical atlas. A patient-specific tumor shape was generated from the medical image segments. The algorithm used to define deformities of the cranial nerves, along with the position and shape of the tumor, was developed using a mass–spring–damper model. The system was evaluated by 9 neurosurgeons and 4 university students. RESULTS: The system successfully visualized the displaced structures of cranial nerves and was useful for surgical planning, enabling a more accurate estimation of the surgical problem. CONCLUSION: We here propose a 3D mobile visualizing simulation system for estimating cranial nerve tracts displaced by a brain stem tumor (CranialNvSim). The system was shown to be useful for surgical planning.

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BACKGROUND: Subarachnoid hemorrhages may occur spontaneously from a ruptured cerebral aneurysm. The placement of clips around the neck of the aneurysm (clipping) is one of the very common surgical treatments. However, clipping is a challenging surgery for most neurosurgeons. To help support the surgeon’s decision-making process and preoperative surgical planning, we developed a VR clipping simulator (ClipSim).

METHODS: High definition 3DCG models such as aneurysms, arteries, and brain were segmented by Amira® software (FEI, Hillsboro, OR) and surgical clips were modeled by Maya® software (Autodesk, San Rafael, CA). These models were integrated and simulated into Unity® (Unity Technologies, San Francisco, CA) software.

RESULTS: We successfully developed a real-time, interactive, clipping simulator with an aneurysm deformable model used by PhysX real-time physics engine (Ageia, Santa Clara, CA). In conclusion, the simulator may be useful prior to surgery during the surgeon’s decision making process for selecting the most appropriate clips.

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