Differentiation betvvcen sigrnoid volvulus and free air on supine abdonlinal radiographs: the 'I iver overlap sign' versus the 'football sign' from page 25 In conclusion it must be stated that having seen many cases of free air with a 'football sign' and a few cases of sig- moid volvulus with a 'liver overlap sign', the former diagnosis was fa- voured. This was also a provisional clini- cal diagnosis.The fact that free air was conclusively excluded on chest radio- graphs and a left side down decubitus abdominal radiograph, should have made gastrografin studies of the upper and lower gastrointestinal tract to search for a perforation unnecessary. The gastrografin enema was, however, of considerable benefit in the diag- nosis and treatment of the sigmoid volvulus. If only a supine abdominal radio- graph had been available,which might sometimes be the case, it would have been very difficult to distinguish be- tween a ruptured hollow viscus and sigmoid volvulus. Other signsof pneu- moperitoneum or sigmoid volvulus also proved to be unhelpful. (In the first case of possible free air they added to the confusion). The clinical features did not aid in differentiating between CASE REPORT Unusual foreign bodies in the oesophagus WFC van Gelderen FFRad(D), Consultant Radiologist KSCheng FRCS(Ed),FRACS, Consultant Surgeon, Department of Radiology, Wanganul Base Hospital, New Zealand. A 70 year old man with a known long segment benign stricture of the lower oesophagus, presented again with dysphagia and the stricture was dilated. Subsequent chest radiographs demonstrated signs of a pneumome- diastinum. An Ultravist 300 non-ionic con- trast (Schering AG, Germany) swal- low demonstrated a localized, con- tained perforation of the left lower these two conditions and without fur- ther conventional radiographs and contrast studies the diagnosis could not have been made. This case illus- trates that neither the 'football sign' nor the 'liver overlap sign' are invari- able, infallible indicators. References I. Young WS, Engelbrecht HE, Stoker A. Plain film analysis in sigmoid volvulus. Cli" Radio11978; 29: 553- 560. 2. Janzen DL, Heap Sw. Organo-axial volvulus of the sigmoid colon. Australas Radiol; 1992: 332-333. 3. Rice RP,Thompson WM, Gedgaudas RK.The diagnosis and significance of extraluminal gas in the abdomen. Radiol Cli" North Am 1982: 20(4): 819-837. oesophagus. Half a dozen rec- tangular low attenuation foreign bodies were noted within the area of rupture and within the distal oesophagus (Figure 1). The patient had not been permitted to have anything by mouth and denied having had anything to eat or drink. On more persistent questioning, however, he admitted to being rather partial to lozenges and had not thought that these would be contraindicated. He had surreptitiously sucked the lozenges one by one in the ward, and subsequently the nucleus of each lozenge, a thin hard square wafer, had found its way down to the oesophagus fully intact 26 SA JOURNAL OF RADIOLOGY. June 1997 in shape, though reduced in size. These wafers were eloquently dem- onstrated on Ultravist swallow. The remains of the lozenges were removed at subsequent oesophagos- copy and the patient made an unre- markable recovery with a follow-up contrast swallow demonstrating reso- lution of the contained rupture. Figure 1: Localized contained rupture left lower oesophagus shown at contrast swallow. Note multiple rectangular low attenuation foreign bodies (arrows) which are the residue of lozenges sucked by the patient over the preceding hours.