Mediastinal Duplication Cyst on 99mTc Pertechnetate Scan

Abstract

A 3-year-old boy presented with intermittent abdominal pain, melena, and anemia since 2 months. Upper gastrointestinal endoscopy did not reveal any significant abnormality. The child was then referred for 99m Tc-pertechnetate scan to rule out the presence of ectopic functioning gastric mucosa. 99m Tc-pertechnetate scan revealed abnormal tracer accumulation in the thoracic region, which persisted in the delayed images, suspicious for being ectopic gastric mucosa. Subsequently, ultrasound and contrastenhanced CT (CECT) scans of the chest revealed a large multiseptate cystic lesion in the retrocardiac region, corresponding to the site of increased tracer uptake on 99m Tc-pertechnetate scan.