Aim: Adenomyoma is an exceptionally rare hamartoma in the small intestine. Few data have been reported on the features of this rare disease. The aim of this study was to describe the ultrasound (US) characteristics of small intestinal adenomyomas. Material and methods: This retrospective study analyzed the clinical features and US data of 15 pediatric patients diagnosed as small intestinal adenomyomas in the age range between 1 day to 12 years in our hospital during 2014-2021.
Results: The clinical manifestations of all the small intestinal adenomyomas were abdominal pain, vomiting or/and hemafecia. The small intestinal adenomyoma usually acted as the lead point of secondary intussusception. They were identified in the ileum (n=11), jejunum (n=2), and Meckel's diverticulum (n=2). The diagnostic accuracy (the concordance rate between US diagnosis and pathological diagnosis) of small intestinal adenomyoma was 73.3%. The small intestinal adenomyoma had approximately 1.0-3.0 cm, were typically located in the submucosal region, had the basal part wide and without a pedicle, and its boundaries were clear. The mass protruded into the intestinal cavity, and showed oval hypoechoic polycystic echo nodules, containing multiple small quasi-circular or irregular cysts of different sizes surrounded by solid hypoechoic mosaic areas. The color Doppler US showed in the solid hypoechoic areas of the mass abundant or sparse blood flow signals.Conclusions The US findings of small intestinal adenomyomas in children are characteristic, and US is valuable in the identification of intestinal adenomyomas in children.