Extraperitoneal pneumography; a preliminary report.

The presence of a gas in the retroperitoneal tissues makes possible a radiologic visualization of retroperitoneal organs and masses. Retropneumoperitoneum is accomplished by the injection of oxygen at low pressure into the tissues lying between the coccyx and the rectum. The technique of injection is simple and no complications have occurred with the first 30 cases. This method is particularly useful in outlining the kidneys and adrenal glands.