Diagnostic Ability of Ultrasonography Compared with Computed Tomography for Assessing Rectal Feces

Objectives: Chronic constipation is a common gastrointestinal disorder, and management is crucial. Computed tomography (CT) is useful for evaluating rectal fecal mass but limited owing to radiation exposure, cost, and inaccessibility at certain facilities. Ultrasonography (US) avoids these pitfalls, but it is unknown whether it accurately assesses rectal feces. In this study, we evaluated the diagnostic performance of US compared with CT as the gold standard for assessing rectal feces. Methods: We prospectively evaluated rectal fecal mass retention using US performed within 1 h of CT to assess the degree of agreement between methodologies. Rectal stool findings were evaluated on three levels: no stool (R1), presence of stool (R2), and hard stool filling (R3). Results: The sample included 100 patients (55 men, 45 women), of whom 47 were constipated. The kappa coefficients for rectal content detection were excellent between US and CT (p