Dual-modality phantom for evaluating x-ray/echo registration accuracy

Transcatheter interventions for structural heart disease demand real-time visualization of catheter devices and their relationship to cardiac anatomy. Co-registration of x-ray fluoroscopy with echocardiography has been proposed to provide the necessary device and soft tissue visualization for these procedures. Development of real-time 3D x-ray/echo registration systems with device tracking has been hampered by the lack of a suitable test model. This study presents a phantom that is compatible with x-ray, CT, transthoracic (TTE), and transesophageal echo (TEE) for testing the feasibility and accuracy of new registration solutions. The phantom consists of a 20.3-cm diameter, 15-cm tall cylindrical shell with acoustic windows for TTE and an access port for a TEE probe. The interior contains 24 dual-modality targets, 5-mm in diameter, suspended in a three-turn helix occupying a volume that is similar to an adult heart. An ultrasound-compatible, tissue-mimicking slurry medium fills the remainder of the phantom. The dual-modality targets are agar based with barium sulfate (BaSO4) powder and glass beads added to generate contrast in both x-ray and ultrasound. Appropriate concentrations of these additives were determined experimentally with contrast measurements in x-ray, CT, and ultrasound. Selected concentrations were 150 mg/mL BaSO4 and 100 mg/mL of 53-63 μm diameter glass beads. Average target contrast (± SD) was 16% ± 2% in x-ray fluoroscopy (90 kV) and 1805 ± 99 HU in CT (100 kV). In ultrasound, target CNR was 4.30 ± 0.62 in 2D B-mode and 4.03 ±1.06 in 4D-mode images acquired at a center frequency of 2.8 MHz.

[1]  YingLiang Ma,et al.  Registration of 3D trans-esophageal echocardiography to X-ray fluoroscopy using image-based probe tracking , 2012, Medical Image Anal..

[2]  Kawal S. Rhode,et al.  Rapid Image Registration of Three-Dimensional Transesophageal Echocardiography and X-ray Fluoroscopy for the Guidance of Cardiac Interventions , 2010, IPCAI.

[3]  Michael A. Speidel,et al.  Clinical feasibility of x-ray based pose estimation of a transthoracic echo probe using attached fiducials , 2018, Medical Imaging.

[4]  K. Rhode,et al.  Extended-field-of-view three-dimensional transesophageal echocardiography using image-based X-ray probe tracking. , 2013, Ultrasound in Medicine and Biology.

[5]  Prashanth,et al.  Conscious Sedation Versus General Anesthesia for Transcatheter Aortic Valve Replacement , 2017 .

[6]  T J Hall,et al.  Ultrasound contrast-detail analysis: a preliminary study in human observer performance. , 1993, Medical physics.

[7]  Volker Rasche,et al.  Fusion of three-dimensional X-ray angiography and three-dimensional echocardiography , 2008, International Journal of Computer Assisted Radiology and Surgery.

[8]  S. Pocock,et al.  Transcatheter aortic-valve implantation for aortic stenosis in patients who cannot undergo surgery. , 2010, The New England journal of medicine.

[9]  K. Shioda,et al.  Safety and efficacy of minimalist approach in transfemoral transcatheter aortic valve replacement: insights from the Optimized transCathEter vAlvular interventioN-Transcatheter Aortic Valve Implantation (OCEAN-TAVI) registry. , 2018, Interactive cardiovascular and thoracic surgery.

[10]  Andrew S. Mugglin,et al.  Surgical or Transcatheter Aortic‐Valve Replacement in Intermediate‐Risk Patients , 2017, The New England journal of medicine.

[11]  Michael A Speidel,et al.  A dynamic model‐based approach to motion and deformation tracking of prosthetic valves from biplane x‐ray images , 2018, Medical physics.

[12]  Charles Hatt,et al.  A method for measuring the accuracy of multi-modal image fusion system for catheter-based cardiac interventions using a novel motion enabled targeting phantom , 2011, 2011 Annual International Conference of the IEEE Engineering in Medicine and Biology Society.

[13]  W. Segars,et al.  4D XCAT phantom for multimodality imaging research. , 2010, Medical physics.

[14]  Michael A. Speidel,et al.  Real-time 3D image fusion system for valvular interventions based on echocardiography and biplane x-ray fluoroscopy , 2019, Medical Imaging.