Cystic Masses of Lower Abdomen in Infants: Differential Diagnosis on Ultrasound.

Jee,  Sung Woo; Lee,  Hee Jung; Sohn,  Cheul Ho; Kim,  Hong; Woo,  Seong Ku; Suh,  Soo Jhi

Journal of Korean Society of Medical Ultrasound 1997;16(3): 257-263.

Sung Woo Jee, Hee Jung Lee, Cheul Ho Sohn, Hong Kim, Seong Ku Woo, Soo Jhi Suh

Department of Diagnostic Radiology, Keimyung University School of Medicine, Korea.

Published online: January 1, 2001.

ABSTRACT

PURPOSE: For the differential diagnosis of the lower abdominal cystic masses in neonates and infants on ultrasound. MATERIALS & METHODS: Surgically and clinically diagnosed ninteen infants with lower abdominal cystic masses included in the study. The study group consisted of three lymphangiomas, five enteric duplication cysts, four non-pancreatic pseudocysts, five ovarian cysts (uncomplicated), and two hydremetrocolposes. We retrospectively evaluated the size, shape (round, lobulating), wall thickness (thin, thick), wall patterns (double layering, peristaltic, daughter cyst, uniform, irregular), and contents(anechoic, debris or fluid-debris level, septum)of the cysts. RESULTS: The mean sizes of the cystic masses were 105x74x175 mm in lymphangiomas, 97x38x57 mm in non-pancreatic pseudocysts, 72x35x59 mm in enteric duplication cysts, 52x32x42 mm in ovarian cysts, and 54x37x53 mm in hydrometrocolposes. The shape of the cyst was round in all of the enteric duplication cysts and ovarian cysts, and one lymphangioma and one hydrometrocolpos. Two hydrometrocolposes showed the tapered lumens toward the pelvic cavity. All ovaian cysts and one enteric duplication cyst had thin walls, and the others were thik. The patterns of the cyst walls were double layering or peristaltic in two enteric duplication cysts and daughter cyst in all ovarian cysts. The contents of the cysts showed anechoic in all ovarian cysts and four enteric duplication cysts. All of the lymphangiomas and non-pancreatic pseudocysts contained both debris or fluid-debris level and septa in the lumen. CONCLUSION: Ultrasound was helpful in the differential diagnosis of the lower abdominal cystic masses in infants based on the shape, wall thickness, wall patterns, and contents of the cysts. The shape of the cyst would be helpful for the diagnosis of hydrometrocolpos. The patterns of the cyst would be helpful for the diagnosis of enteric duplication cyst and ovarian cyst with the findings of double layering or peristaltic and daughter cyst, respectively.

Keywords: Infants. Newborn. US studies; Abdomen. US studies; Abdomen. cysts