The Technic of Intravenous Urography

Abstract

THE diagnostic value of intravenous urography is at present still underestimated, due to the failure to obtain a greater proportion of cases in which the urinary tract is filled and visualized on the film. The causes of the failure of filling of the urinary tract are either faulty technic or anuria, very often the result of an acute renal colic or cystoscopy. In acute renal colic a good readable film is often obtained several hours after the injection of the drug. In the case of cystoscopy, on the other hand, we postpone the injection for three days, or until the normal urinary excretion is established. In order to avoid loss of time, we, therefore, recommend that the intravenous method precede the retrograde method. The secret of success in obtaining a greater number of readable films lies in the method of compression used before the X-ray exposure. The compression is applied over the lower abdomen at a point at which the ureter crosses the common iliac artery. According to Cunningham's “Anatomy,” “The ureters lie in front of the termination of the common iliac arteries at the level of the intertubercular plane and about 1.5 inches from the median plane” (Fig. 1). The apparatus used for compression consists of the following parts (Fig. 2): 1. A small wooden box, 5 × 3 × 1.5 inches, with one side open. 2. A small rubber bag, 4 × 2.5 inches, with a rubber tube attached to it. 3. A monometer, dial type. 4. A rubber bulb, such as used in a sphygmomanometer. 5. A “T” glass connection. The patient is in either the supine or the upright position. The wooden box, holding the rubber bag, is placed, open side down, over the lower abdomen, about 4 inches proximal to the symphysis pubis. The long axis of the box, transverse to the long axis of the body, is held snugly in position by the compression band of the Bucky diaphragm. The three ends of the “T” tube connect, respectively, the rubber tube of the bag, the monometer, and the rubber bulb. The rubber bag is then inflated till a pressure of about 180 mm. of mercury is registered, the pressure being maintained for five minutes, after which an exposure is made. The entire urinary tract proximal to the compression is then invariably filled and a readable film is thus obtained. Another film is exposed immediately after the compression is removed. On the second film the urinary tract distal to the compression is visualized. Technic in Detail, Characteristic Findings The first film is taken before the injection. The exposure is made ventrodorsally with the patient in the horizontal posture on deep expiration. This film demonstrates existing calculi or calcareous deposits which may be obscured by the excreted drug. It also shows the position of the kidney during deep expiration. It is advisable that the patient remain on the X-ray table in the supine position during the injection and until the third exposure is made. Keeping the patient quietly in this position tends to keep the urinary tract filled (Fig. 3).