pyelograms

radiography of the renal pelvis and ureter after injection of a contrast medium; there are two methods: the intravenous method and the retrograde method. Preparation of the patient for pyelography includes clearing the intestinal tract of as much fecal material and gas as possible so that there can be adequate visualization of the urinary tract structures. Usually this is accomplished by administration of a laxative. The evening before the examination the patient is given a light meal and then all foods and fluids are restricted after 9:00 pm.

In the intravenous method the contrast medium is injected intravenously at designated intervals and x-ray films are taken to observe the rate of excretion, the concentration of the contrast medium in the pelvis and calices of the kidney, and the outline of the ureters and urinary bladder. The possibility of an allergic reaction to the contrast medium must always be considered. Drugs such as epinephrine and hydrocortisone should be on hand for use in the event of a serious allergic reaction. The patient may experience a mild transitory sensation of warmth, flushing of the face, or a salty taste in the mouth, but these should last only a few moments. Symptoms of anaphylaxis demand immediate treatment.

The retrograde method involves introduction of the contrast medium by way of ureteral catheters. This procedure may be done when special studies of certain parts of the urinary tract are indicated, when adequate concentration of the contrast medium cannot be achieved by the intravenous method, or when a chronic illness, such as diabetes mellitus, affects renal arterioles and prevents intravenous injection of contrast medium.