Intra-Arterial Image Guidance With Optical Frequency Domain Reflectometry Shape Sensing

Intra-arterial liver cancer therapies, such as trans-arterial chemoembolization, are the preferred therapeutic approaches for advanced hepatocellular carcinoma. However, these palliative techniques are challenging for delivering therapeutic agents selectively in the tumor without real-time 3-D visualization of the catheter within the hepatic arteries. The objective of this paper is to develop and evaluate in pre-clinical tests an advanced interventional guidance platform using a distributed strain sensing device based on optical frequency-domain reflectometry (OFDR) to track the tip and shape of a catheter. The scattering properties of a fiber triplet are enhanced by focusing an ultraviolet beam on these fibers, producing a fully distributed strain sensor, which avoids interpolation errors observed with traditional shape tracking systems. A 3-D roadmap of the hepatic arteries is obtained from a combined fully convolutional and residual networks trained on MR angiography and combined with a 4-D flow dynamic sequence enabling to map blood flow velocities. An anisotropic curvature matching method is proposed to map the sensed data onto pre-operative MR and using 3-D ultrasound to correct for non-rigid deformations. Experiments were conducted in a controlled environment setting as well as in both synthetic phantoms and in five porcine models to assess the performance for device navigation, yielding satisfactory tracking accuracy with 3-D mean errors of 2.8 ± 0.9 mm. We present the first pilot study of MR-compatible UV-exposed OFDR optical fibers for non-ionizing device guidance in intra-arterial procedures, with the potential of avoiding multiple hospitalizations required to perform invasive selective chemoembolizations.