Optimizing Ultrasonographic Diagnosis of Paediatric Enteric Duplication Cysts: Current Practices and Future Innovations

Duplication cysts are rare congenital malformations located anywhere along the mesenteric side of the gastrointestinal tract, usually observed within the first two years of life. They most commonly occur in the small bowel, originating from the midgut, with the distal ileal portion being the most frequently involved segment. The nonspecific clinical manifestations, ranging from asymptomatic presentations to acute symptoms and complications, make diagnosis challenging. Other abdominal cysts and Meckel’s diverticulum should be considered as alternative diagnoses when duplication cysts are suspected. Abdominal and intestinal ultrasound is the preferred first imaging modality for assessing enteric cysts in the paediatric population due to its wide accessibility, lack of ionizing radiation exposure, no need for contrast administration, and shortened image acquisition duration. Important and unique features of ultrasound examination include its dynamic nature and the ability to deliber-ately compress the cystic mass under the transducer. The ultrasound examination is usually per-formed using a low-frequency sector transducer, as well as a high-frequency linear transducer for enhanced resolution of the intestinal wall. The characteristic sonographic wall appearance of the cystic mass shows a layered pattern, known as the "gut signature sign". Other valuable indicators for identifying enteric cysts on ultrasound include the "5-layer sign", the "split wall sign", and the presence of wall peristalsis. Endoscopic ultrasound is another imaging modality for assessing the presence of duplication cysts, offering the possibility of fine needle aspiration in more complicated cases. Prenatal ultrasound can provide an early diagnosis of duplication cysts during pregnancy, enabling timely access to treatment. Newer technologies, such as HDlive and 3D multiplanar views, enhance the utility and relevance of ultrasound in diagnosing enteric cysts. Complementary imaging modalities such as CT and MRI can be useful in cases of diagnostic uncertainty following ultrasound examination. Surgical intervention with cyst excision is the preferred treatment method, but adjacent bowel resection must be considered when performing the procedure. The aim of this review is to provide a comprehensive overview of the literature on ultrasonographic examination of enteric duplication cysts, highlighting characteristic features and potential adjunctive techniques to facilitate accurate diagnosis.