Catheter pose-dependent virtual angioscopy images for endovascular aortic repair: validation with a video graphics array (VGA) camera

Previous research reported catheter pose-dependent virtual angioscopy images for endovascular aortic repair (EVAR) (phantom studies) without any validation with video images. The goal of our study focused on conducting this validation using a video graphics array (VGA) camera. The spatial relationship between the coordinate system of the virtual camera and the VGA camera was computed with a Hand-Eye calibration so that both cameras produced similar images. A re-projection error of 3.18 pixels for the virtual camera and 2.14 pixels for the VGA camera was obtained with a designed three-dimensional (3D) printed chessboard. Similar images of the vessel (3D printed aorta) were acquired with both cameras except for the different depth. Virtual angioscopy images provide information from inside the vessel that may facilitate the understanding of the tip position of the endovascular tools while performing EVAR

Three-dimensional guidance including shape sensing of a stentgraft system for endovascular aneurysm repair

Purpose!#!During endovascular aneurysm repair (EVAR) procedures, medical instruments are guided with two-dimensional (2D) fluoroscopy and conventional digital subtraction angiography. However, this requires X-ray exposure and contrast agent is used, and the depth information is missing. To overcome these drawbacks, a three-dimensional (3D) guidance approach based on tracking systems is introduced and evaluated.!##!Methods!#!A multicore fiber with fiber Bragg gratings for shape sensing and three electromagnetic (EM) sensors for locating the shape were integrated into a stentgraft system. A model for obtaining the located shape of the first 38 cm of the stentgraft system with two EM sensors is introduced and compared with a method based on three EM sensors. Both methods were evaluated with a vessel phantom containing a 3D-printed vessel made of silicone and agar-agar simulating the surrounding tissue.!##!Results!#!The evaluation of the guidance methods resulted in average errors from 1.35 to 2.43 mm and maximum errors from 3.04 to 6.30 mm using three EM sensors, and average errors from 1.57 to 2.64 mm and maximum errors from 2.79 to 6.27 mm using two EM sensors. Moreover, the videos made from the continuous measurements showed that a real-time guidance is possible with both approaches.!##!Conclusion!#!The results showed that an accurate real-time guidance with two and three EM sensors is possible and that two EM sensors are already sufficient. Thus, the introduced 3D guidance method is promising to use it as navigation tool in EVAR procedures. Future work will focus on developing a method with less EM sensors and a detailed latency evaluation of the guidance method

Supplementary document for Virtual Hall Sensor Triggered Multi-MHz Endoscopic OCT Imaging for Stable Real-Time Visualization - 6821416.pdf

Supplement

3D OCT Visualization of Thread

Highlighting the details of a threaded structure, suggesting the system's ability to capture fine structural details

OCT Imaging of Constant Frequency Profile

Three-dimensional representation of a constant frequency profile, indicating the system's capability in representing consistent patterns

3D OCT Visualization of Weld Seam

A volumetric representation displaying details of a weld seam, showing the imaging system's potential use in industrial settings

OCT Imaging in Real-time

Instant visualization of the OCT procedure, indicating reduced NURD presence when fiducial markers are in sight, suggesting the BEMF-triggered system's accuracy

Comparative OCT Imaging with and without BEMF Triggering

Demonstrating the impact of BEMF triggering on image quality, the comparison highlights the image without triggering (top) versus the BEMF-triggered image (bottom), emphasizing the improved clarity and reduced artefacts achieved with the triggering approach, all without any additional processing

OCT Imaging of Variable Frequency Profile

Demonstrating variations within a variable frequency profile, indicating the system's potential versatility in imaging structures with varied patterns