1. Open‐chest cardiac ultrasound‐mediated imaging with a vacuum coupler.
- Author
-
Mathuria, Nilesh, Vishwanath, Krithik, Brero, Giorgio, Fallon, Blake C., Martino, Antonio, Willson, Richard C., Filgueira, Carly S., and Bouchard, Richard R.
- Abstract
Background Purpose Methods Results Conclusions A fundamental obstacle for the preclinical development of ultrasound‐(US) mediated cardiac imaging remains cardiac motion, which limits interframe correlation during extended acquisition periods.To address this need, we present the design and implementation of a 3D‐printed vacuum coupler that stabilizes a US transducer on the epicardial surface of the heart for feasibility assessment and development of advanced, cardiac, US‐mediated imaging approaches.The vacuum coupler was 3D printed with biocompatible resins and secured with a standard intraoperative suction aspirator. US‐mediated imaging (i.e., B‐mode and photoacoustic [PA] imaging) was performed in an open‐chest porcine model with and without the vacuum coupler. Based on inter‐frame displacement tracking and cross‐correlation (CC) coefficients, changes in frame motion and stability were compared for each imaging mode/configuration through a prolonged (∼1 min) acquisition, while the impact on PA‐based SO2 accuracy was assessed.When compared to conventional handheld imaging, stand‐off imaging, and coupler without suction, epicardial imaging with the vacuum coupler and suction applied led to a significantly reduced mean axial displacement of 0.15 mm versus 0.89, 0.49, & 0.49 mm, respectively (
p ‐values ≤ 8.65e‐7). Comparing the coupler without suction to that with suction applied, physiologically unrealistic SO2 estimates reduced from 1.72 to 0.81%, respectively, and lateral interframe displacement reduced from 4.58 to 2.01 mm, respectively (p ‐value = 5.07e‐23). Overall, reduced cardiac tissue motion and increased interframe CC coefficient (baseline = 0.43 vs. coupler with suction = 0.80) allow for more accurate PA unmixing.Epicardial US‐mediated imaging with a vacuum coupler reduces cardiac motion artifact, providing a consistent sampling of an intended region of interest (ROI) over multiple cardiac cycles. This could help facilitate the development of advanced US‐mediated imaging, which is often hindered by cardiac motion. Stable implementation of these imaging techniques could allow for intra‐operative assessments of local cardiac perfusion as well as tissue characterization. [ABSTRACT FROM AUTHOR]- Published
- 2024
- Full Text
- View/download PDF