Transabdominal Ultrasound Measured Rectal Diameter for Identifying Fecal Impaction in Children With Functional Constipation: A Diagnostic Accuracy Study. - Sunkari K; Siddiqui MS; Mishrikotkar PS; Engade MB; Totla RJ; Joshi PM; Chandra SS; Varghese AM (Cureus, 2025)