Imaging findings and management of diaphragmatic mesothelial cysts in children

Diaphragmatic mesothelial cysts are rare benign congenital lesions with typical imaging findings. To present imaging and treatment outcomes in 30 children with diaphragmatic mesothelial cyst. We conducted a retrospective chart review and recorded demographic data, imaging findings, treatment and US follow-up results, initial and final volume of the cysts and length of follow-up period for each case of diaphragmatic mesothelial cyst in a specialist hospital. The study included 30 children (16 girls, age range 1-17 years, mean age 7.9 years) diagnosed with diaphragmatic mesothelial cyst between January 2010 and December 2015. Imaging findings included thin-walled bilobulated or oval-shape cysts located between the diaphragm and right lobe of the liver. Treatment consisted of percutaneous drainage in 17 children and was successful in all. Cysts disappeared completely in 12 of these 17 children (70.5%, 95% confidence interval [CI] 44-90%). Mean volume reduction was 98%. No complication or mortality was seen. The other 13 children were followed with US without treatment. In 4 of these 13 children (30.8%, 95% CI 9-61%), cysts spontaneously decreased in size. No cyst increased in size. In children with typical imaging findings, percutaneous drainage appears safe and effective when treatment is deemed necessary.