The technique of urethrography involves retracting the foreskin and cleaning the glans. A Foley catheter is inserted 1-2cm to the navicular fossa where the balloon is inflated with approximately 1-2ml of water.
The penis is placed to one side and control radiographs are taken in the AP position and right anterior oblique if the penis is placed to the left and left anterior oblique if the penis is placed to the right.
Clamps are not used in our institution and good results may be obtained by anchoring the catheter, even loosely, to the drape or applying very gentle forward pressure when instilling contrast material.
A contrast strength of 150mg/ml is used. Initially very gently instillation of contrast is required as urethral injury, if present, is exceedingly painful during passage of contrast.
It is normal for contrast to be held up at the external urethral sphincter. When this occurs, gentle, continuous pressure usually results in sudden passage of contrast into the posterior urethra and bladder.
Radiographs are taken when there is appropriate filling of the urethra or an abnormality is encountered. Following retrograde urethrography, antegrade urethrography should be performed. The optimum filling of the bladder to enable this is > 300ml, though this varies from patient to patient. In the setting of major trauma, the patient may not be able to stand and in this case the patient is asked to micturate when the table is tilted as far head-up as tolerated. Oblique single shot(s) during micturition only are required.
See Urethra - male for the anatomy.