LAUSR

1 Duodenal duplication cysts are rare. Definitive endoscopic therapy and marsupialization of symptomatic duplication cysts have been reported with the use of a needle-knife, sphincterotome, or polypectomy snare. Here we describe a case in which marsupialization of a duodenal duplication cyst was performed on a 3-year-old child by use of a variant of the insulated-tipped (IT) knife (Video 1, available online at www.VideoGIE.org). The child was first brought, at the age of 15 months, to another hospital because of recurrent abdominal pain with vomiting and acute pancreatitis on separate occasions. He was referred to our hospital when he was 3 years old for the management of a suspected type III choledochal cyst. Abdominal US showed a cystic lesion suggestive of an enteric duplication cyst. MRCP was done to further evaluate the cyst and showed a 5.24.01.6-cm cystic structure posterior to the second part of the duodenum (Fig. 1). The distal common bile duct and common channel were seen coursing through the anterior wall of the cyst and appeared to communicate with the lumen of the cyst. The case was discussed at the hospital multidisciplinary meeting, and it was concluded that the imaging features were consistent with duodenal duplication cyst instead of a type III choledochal cyst. Hence, the decision was made to treat the cyst endoscopically.