An unusual congenital dorsal midline thoracic mass

To describe the presentation and investigation of an unusual form of congenital dorsal midline thoracic mass.

An infant born by emergency Caesarean section at 34 weeks gestation was found to have a large dorsal midline thoracic mass. The infant had normal neurological function in all limbs. Radiological investigation showed no abnormality in the vertebrae. Ultrasonographic investigation suggested the mass to consist of subcutaneous oedema. The mass resolved completely within the first 2 weeks.

The lesion observed in this infant represents a very unusual location for a benign condition caused by cervical pressure on the presenting fetal part. The use of ultrasonography enabled rapid exclusion of the more common, potentially serious, causes of a congenital midline dorsal thoracic mass.