Project 1: US-guided Percutaneous Liver Tumor Ablation
Tumor Identification
Image Registration

Tumor Identification

Objective: In US-guided liver tumor ablations, tumor identification remains challenging in some scenarios, such as similar acoustic characteristics between the tumor and surrounding tissue, irregular tumor locations (e.g., high liver dome), and tumor mimics (e.g., cirrhotic regenerative nodules, prior ablation sites). While multimodal registration techniques have been extensively studied to address these limitations, they have not yet become a standard clinical component due to the high complexity and computational demands. Therefore, this work aims to develop a clinically feasible 2D US-CT/MRI registration approach to reduce inter-physician variability in interpreting structural details, thereby facilitating applicator guidance during procedures.

3D US liver System
Tumor Coverage Evaluation
3D US

Tumor Coverage Evaluation

Objective: Complete tumor coverage by the thermal ablation zone and with a safety margin (5 or 10 mm) is required to achieve the entire tumor eradication in liver tumor ablation procedures. However, 2D ultrasound (US) imaging has limitations in evaluating the tumor coverage by imaging only one or multiple planes, particularly for cases with multiple inserted applicators or irregular tumor shapes. In this paper, we evaluate the intra-procedural tumor coverage using 3D US imaging and investigate whether it can provide clinically needed information. Our proposed method can evaluate the intra-procedural tumor coverage and intuitively provide applicator adjustment information for the physician. Our 3D US-based method is compatible with the constraints of conventional US-guided ablation procedures and can be easily integrated into the clinical workflow.

Needle Identification
Project 2: Integration of Magnetic Tracking into Fluoroscopy-guided Interventions

In collaboration with Northern Digital Inc. (NDI), I contributed to pioneering the integration of magnetic tracking into fluoroscopy-guided interventions.

Seamless Integration of Magnetic Tracking
Radiolucent Field Generator

Seamless Integration of Magnetic Tracking

Objective: The 2D projective nature of X-ray radiography presents significant limitations in fluoroscopy-guided interventions, particularly the loss of depth perception and prolonged radiation exposure. Integrating magnetic trackers into these workflows is promising; however, it remains challenging and under-explored in current research and practice. To address this, we employed a radiolucent magnetic field generator (FG) prototype as a foundational step towards seamless magnetic tracking (MT) integration. A two-layer FG mounting frame was designed for compatibility with various C-arm X-ray systems, ensuring smooth installation and optimal tracking accuracy. To overcome technical challenges, including accurate C-arm pose estimation, robust fluoro-CT registration, and 3D navigation, we proposed the incorporation of external aluminum fiducials without disrupting conventional workflows. Overall, our results demonstrated the efficacy and clinical applicability of the MT-assisted approach. To the best of our knowledge, this is the first study to integrate a radiolucent FG into a fluoroscopy-guided workflow.

Virtual Fluoroscopy using Magnetic Tracking