Virtual linear measurement system for accurate quantification of medical images

Virtual reality (VR) has the potential to aid in the understanding of complex volumetric medical images, by providing an immersive and intuitive experience accessible to both experts and non-imaging specialists. A key feature of any clinical image analysis tool is measurement of clinically relevant anatomical structures. However, this feature has been largely neglected in VR applications. The authors propose a Unity-based system to carry out linear measurements on three-dimensional (3D), purposefully designed for the measurement of 3D echocardiographic images. The proposed system is compared to commercially available, widely used image analysis packages that feature both 2D (multi-planar reconstruction) and 3D (volume rendering) measurement tools. The results indicate that the proposed system provides statistically equivalent measurements compared to the reference 2D system, while being more accurate than the commercial 3D system.