Tracked Foley catheter for motion compensation during fusion image-guided prostate procedures: a phantom study.

Uncorrected patient or prostate motion may impair targeting prostate areas during fusion image-guided procedures. We evaluated if a prototype "tracked Foley catheter" (TFC) could maintain fusion image alignment after simulated organ motion.

A pelvic phantom model underwent magnetic resonance imaging (MRI), and the prostate was segmented. The TFC was placed in the phantom. MRI/ultrasound (US) fusion was performed. Four trials were performed varying motion and TFC presence/absence: (1) TFC/no-motion, (2) TFC/motion, (3) no-TFC/no-motion, and (4) no-TFC/motion. To quantify image alignment, screen captures generated Dice similarity coefficient (DSC) and offset distances (ODs) (maximal US-to-MRI distance between edges on fusion images). Three anatomical targets were identified for placement of a needle under fusion guidance. A computed tomography scan was used to measure system error (SE), i.e., the distance from needle tip to intended target.

The TFC presence improved MRI/US alignment by DSC 0.88, 0.88, 0.74, and 0.61 in trials 1, 2, 3, and 4, respectively. Both OD (trial 2 versus trial 4, 4.85 ± 1.60 versus 25.29 ± 6.50 mm, p < 0.001) and SE (trial 2 versus trial 4, 6.35 ± 1.31 versus 32.16 ± 6.50 mm, p < 0.005) were significantly lower when the TFC was present after artificial motion, and significantly smaller OD when static (trial 1 versus trial 3, 4.29 ± 1.24 versus 6.42 ± 2.29 mm, p < 0.001).

TFC provided better image alignment with or without simulated motion. This may overcome system limitations, allowing for more accurate fusion image alignment during fusion-guided biopsy, ablation, or robotic prostatectomy.

European radiology experimental. 2020 Apr 16*** epublish ***

Graham R Hale, Filippo Pesapane, Sheng Xu, Ivane Bakhutashvili, Neil Glossop, Baris Turkbey, Peter A Pinto, Bradford J Wood

Center for Interventional Oncology, Radiology and Imaging Sciences, National Cancer Institute, National Institutes of Health, Bethesda, MD, USA., Center for Interventional Oncology, Radiology and Imaging Sciences, National Cancer Institute, National Institutes of Health, Bethesda, MD, USA. ., Arcitrax, Toronto, Canada., Molecular Imaging Program, National Cancer Institute, National Institutes of Health, Bethesda, MD, USA., Urologic Oncology Branch, National Cancer Institute, National Institutes of Health, Bethesda, MD, USA.