Following Plain radiograph showing both chest and abdomen. The diagnosis is

(A) Pneumoperitoneum # PNEUMOPERITONEUM is pneumatosis (abnormal presence of air or other gas) in the peritoneal cavity, a potential space within the abdominal cavity. When present, it can often be seen on radiography, but small amounts are often missed, and CT scan is nowadays regarded as a criterion standard in the assessment of a pneumoperitoneum. CT can visualize quantities as small as 5 cm3 of air or gas.> Causes:> Perforated duodenal ulcer- The most common cause of rupture in the abdomen. Especially of the anterior aspect of the first part of the duodenum. Perforated peptic ulcer Bowel obstruction Ruptured diverticulum Penetrating trauma Ruptured inflammatory bowel disease (e.g. megacolon)> Necrotising enterocolitis/Pneumatosis coli Bowel cancer Ischemic bowel Steroids> After laparotomy After laparoscopy Breakdown of a surgical anastomosis Bowel injury after endoscopy Peritoneal dialysis Vaginal insufflation (air enters via the fallopian tubes, e.g. water-skiing, oral sex) Colonic or peritoneal infection From chest (E.g. Bronchopleural fistula) Non-invasive PAP (positive airway pressure) can force air down duodenum as well as down trachea.