The "football" or "air dome" sign was described as a "New Roentgen Sign" in 1960 by Miller.1 Prior to this the usual supine film for free air in the peritoneal cavity was considered nondiagnostic. In the newborn the "football" sign is pathognomonic of free air in the abdomen. The oval shadow of the entire abdomen is the "football," and the falciform ligament of the liver is seen as the "seam of the ball." The "seam" is located in the cephalad half of the film, but may be continued caudally by the shadow of the urachus (Fig. 1).
The purpose of this paper is to relate our experiences in 3 cases and to emphasize the value of this diagnostic sign.
Report of Cases
Case 1.—Figure 1 illustrates this roentgen finding in a 2-day-old, 4 lb. (about 1,814 gm.), premature infant who died at 2 days of age. The diagnosis of