Augmented reality-assisted biopsy of soft tissue lesions

Guided biopsy of soft tissue lesions can be challenging in the presence of sensitive organs or when the lesion itself is small. Computed tomography (CT) is the most frequently used modality to target soft tissue lesions. In order to aid physicians, small field of view (FOV) low dose non-contrast CT volumes are acquired prior to intervention while the patient is on the procedure table to localize the lesion and plan the best approach. However, patient motion between the end of the scan and the start of the biopsy procedure can make it difficult for a physician to translate the lesion location from the CT onto the patient body, especially for a deep-seated lesion. In addition, the needle should be managed well in three-dimensional trajectories in order to reach the lesion and avoid vital structures. This is especially challenging for less experienced interventionists. These usually result in multiple additional image acquisitions during the course of procedure to ensure accurate needle placement, especially when multiple core biopsies are required. In this work, we present an augmented reality (AR)-guided biopsy system and procedure for soft tissue and lung lesions and quantify the results using a phantom study. We found an average error of 0.75 cm from the center of the lesion when AR guidance was used, compared to an error of 1.52 cm from the center of the lesion during unguided biopsy for soft tissue lesions while upon testing the system on lung lesions, an average error of 0.62 cm from the center of the tumor while using AR guidance versus a 1.12 cm error while relying on unguided biopsies. The AR-guided system is able to improve the accuracy and could be useful in the clinical application.