A description and explanation of an unexpected echographic appearance in a patient who had sustained an abdominal shotgun wound is presented. In the B-scans, a trail of dense continuous echoes, simulating a comet tail, is seen distal to each lead pellet. This comet tail appearance is shown to be a type of reverberation artifact. The effect of object size, shape, composition, and orientation on the appearance of this artifact is demonstrated.

The comet tail artifact appears as a dense tapering trail of echoes just distal to a strongly reflecting structure. This reverberation type of artifact occurs when there is a marked difference in acoustic impedances between an object and its surround. This paper presents a spectrum of comet tail artifacts seen in clinical practice and discusses their usefulness in decision making.

A case report of an ovarian dermoid tumor perforation the sigmoid colon in a pregnant woman is presentd. Various complications of dermoid perforation are discussed.