Development of a method using transperineal ultrasound movies for automatic evaluation of the contraction of pelvic floor muscles in men after radical prostatectomy

Abstract

　Aim: We aimed to develop a method to automatically evaluate pelvic floor muscle (PFM) contractions using transperineal ultrasound movies of male patients after radical prostatectomy. Methods: Forty transperineal ultrasound movies obtained in a previous study were used. From the discussion between two expert PFMtrainers and automatic trackability, the distance from the pubis to the anorectal junction was determined to be the primary parameter. Seven algorithms were tested to track the pubis and the anorectal junction. The pubis-anorectal junction distance, measured using a software, were compared on two levels of PFMcontraction (good/moderate) subjectively evaluated. Result: Among the seven algorithms, Kernelized Correlation Filter could track the pubis and the anorectal junction during PFM contraction in the 40 movies. The frame rate (fps) was 66‒77 in the Kernelized Correlation Filter. The changing rates of the pubis-anorectal junction distance in the vector and the X-axis lengths were significantly different between the good and moderate contractions that were subjectively evaluated. Conclusion: A method for tracking the pubis and the anorectal junction in ultrasound movies after radical prostatectomy was developed to automatically evaluate PFMcontractions.