Diaphragm strain estimation and analysis using block matching algorithm and interpolation method(PDF)
《中国医学物理学杂志》[ISSN:1005-202X/CN:44-1351/R]
- Issue:
- 2022年第11期
- Page:
- 1360-1368
- Research Field:
- 医学影像物理
- Publishing date:
Info
- Title:
- Diaphragm strain estimation and analysis using block matching algorithm and interpolation method
- Author(s):
- LIU Ziling1; LIU Qiaohong2; YE Xiong3; HAN Ziqi1
- 1. School of Health Science and Engineering, University of Shanghai for Science and Technology, Shanghai 200093, China 2. School of Medical Instruments, Shanghai University of Medicine and Health Sciences, Shanghai 201318, China 3. School of Clinical Medicine, Shanghai University of Medicine and Health Sciences, Shanghai 201318, China
- Keywords:
- Keywords: diaphragm ultrasound image block matching algorithm interpolation method strain estimation
- PACS:
- R318
- DOI:
- DOI:10.3969/j.issn.1005-202X.2022.11.008
- Abstract:
- Abstract: A method combining block matching algorithm with interpolation method is proposed to estimate diaphragm motion displacement and strain for evaluating diaphragm contractility accurately. According to the physiological restraint characteristics of the diaphragm, block matching algorithm based on normalized cross-correlation is used to estimate the cross-correlation function of the region of interest (ROI) of the diaphragm, thereby estimating the integer displacement of the diaphragm motion. Then, a 9-point parabolic interpolation algorithm is used to interpolate the cross-correlation function for obtaining the two-dimensional subpixel displacement of the diaphragm ROI, and the strain is calculated according to the estimated displacement. Finally, the optimal window size is confirmed using the idea of reverse tracking for reducing the displacement tracking error. The whole sequence images of the diaphragm in the inspiratory phase and the fore and aft images of the diaphragm obtained at the beginning and end of inspiratory phase are tracked by the proposed method to analyze the effects of different ROI window sizes on the estimations of diaphragm motion displacement and strain. Experimental results show that there are matching errors in 5×10 and 10×15 windows. The differences in horizontal and vertical displacements tracked by windows of 15×20, 20×25, 25×30 and 30×35 are trivial, and the optimal window size is 25×30. There is no significant difference in diaphragm global strain calculated in whole sequence images or fore and aft images.
Last Update: 2022-11-25