Dynamic transperineal ultrasound in the workup of men with obstructed defecation: a pilot study

BACKGROUND: Dynamic transperineal ultrasound has been used in women for the noninvasive investigation of functional disorders of the posterior pelvic floor, but its use in men has been limited by technical difficulties related to the consistency of the male perineum. OBJECTIVES: The aim of this study was to explore the efficacy of dynamic transperineal ultrasound in diagnosing posterior pelvic floor dysfunction in men. DESIGN: This is a study of diagnostic accuracy. SETTINGS: This study was performed at a public hospital. PATIENTS: Forty-six men with symptoms of obstructed defecation were included. INTERVENTIONS: All patients underwent dynamic transperineal ultrasound 1 week after standard defecography with manometric confirmation when rectoanal dyssynergy was observed. MAIN OUTCOME MEASURES: Images were obtained, and anorectal angles were measured under resting conditions and during maximal strain. The accuracy of the sonographic method in diagnosing pelvic floor alterations was assessed against defecography (reference method). RESULTS: : Anorectal angles measured with ultrasound and defecography were not significantly different under resting conditions or maximum strain. Sonographic and reference method findings were concordant in 41 (89.1%) of the cases (25 with rectoanal intussusceptions, 7 with rectorectal intussusceptions, 8 with rectoanal dyssynergy, and 1 with rectorectal intussusception and dyssynergy). In 1 patient with rectoanal intussusception, dynamic transperineal ultrasound was nondiagnostic (low image quality probably due to dehydration of perineal tissues). Discordant dynamic transperineal ultrasound findings included normal findings in another patient with rectoanal intussusception, diagnosis of rectoanal intussusception in 2 men with rectorectal intussusception, and failure to detect dyssynergy in a second patient with rectorectal intussusception and dyssynergy. The sensitivity, specificity, and Cohen κ indices for dynamic transperineal ultrasound were 92.6%, 90.5%, and 82% (rectoanal intussusception); 81.8%, 100%, and 87% (rectorectal intussusception); 90%, 100%, and 93% (rectoanal dyssynergy). LIMITATIONS: This study was limited by its small size and by the absence of patients with other morphofunctional disorders associated with obstructed defecation. CONCLUSIONS: Dynamic transperineal ultrasound is potentially useful for diagnosis and follow-up of posterior pelvic floor dysfunction in men.