Comparing diagnostic accuracy of transperineal ultrasound using microconvex probe versus conventional linear probe to predict rectal histoendoscopic activity in ulcerative colitis: a paired prospective, head-to-head comparative study

TPUS provides clinically relevant, noninvasive assessment of rectal inflammation in UC. While microconvex TPUS offers technical advantages-particularly axial-plane assessment of posterior wall thickness with favorable diagnostic trends-no single probe demonstrated uniform superiority. These findings highlight the complementary roles of linear and microconvex probes and support ongoing standardization of TPUS.