Skull base anatomy VR
About:
The anatomy of the base of the skull is intricate and complex due to its proximity to many vital nervous system structures. Accessing some of these structures surgically, such as the pituitary gland, often involves approaches like endoscopic transnasal transsphenoidal surgery through the nasal region. An ENT faculty member wanted to create an application that allowed her to teach both ENT residents and neurosurgery residents simultaneously about the anatomy of this region.
This VR tool enables users to visualize the spatial relationships and pathways of numerous clinically important vessels, nerves, and structures in the skull. Models of the skull can be easily manipulated in VR, allowing both ENT and neurosurgery residents to collaboratively learn and understand each other’s perspectives on anatomy. The use of VR and its different features allow for better visualizaton of spatial relationships between structures in densely packed regions like the skull base and ethmoidal area.
A pre and post quiz and survey was conducted, showing the following results:
Statistically significant improvement in anatomy quiz score with VR application usage
85% of participants agreed or strongly agreed that the VR model improved anatomical understanding
Participants reported increased confidence in identifying skull base structures
Role: Project planning, modeling & UI/UX design
Target audience: Otorhinolaryngology (ENT) and neurosurgery residents
Software: Zbrush, Maya, ShapesXR, Unity 3D, Adobe Illustrator
Format: Exe application accessible on Meta Quest 3
Copyrights: © UNMC iEXCEL
Media Feature: ShapesXR feature can be accessed here.
Functional Design
I worked with an ENT faculty member to ensure that her learning objectives were met through different functionalities in the VR application. With a focus on teaching skull base anatomy, I designed the functions of the application with a focus on enhancing spatial understanding of clinically important structures. Functionalities included are visibility adjustments, clipping plane feature to control a clipped view of anatomy, and a labeling and annotation feature.
During the early design phase, I utilized ShapesXR to create the application's interface and functionality in VR. This tool allowed me to prototype in a 3D immersive environment, enhancing my understanding of the user's perspective.
Early mockup in ShapesXR.
UI considerations
Several design factors were carefully considered to enhance the usability of the application. Because residents only had about 15 minutes to use it during their training sessions, the interface needed to support learning rather than distract from it. In addition, most residents were unfamiliar with VR technology, so the design prioritized clarity, efficiency, and ease of navigation. The following UI features were implemented with these goals in mind.
To ensure easy repositioning of models, a snap in place feature was enabled.
Anatomical text labels are placed against a dark background to enhance readability.
A color-blind friendly palette (Okabe-Ito) was used for the pen ink colors in annotation mode to ensure accessibility for all users.
Modeling
I also modeled the assets for this app. I cleaned up the skull models based on segmented CT data provided. Major challenges involved reconstructing the turbinate bones, ethmoid region and various foramina from segmented data. Additionally, I modeled the vessel, sinus and neural pathways from scratch. The final models were decimated to reduce polycount for a VR environment.
Segmented raw data is seen on the left, and high poly cleaned up models are seen on the right.
Reconstruction of ethmoid and turbinate bones, including small foramina such as the anterior and posterior ethmoidal foramen
Cleaning up of holes in segmented data to include only true foramina in the skull
Removal of mandible and separation of cervical vertebra from base of skull