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A urethrogram is a procedure used to show the location and characteristics of a clinically suspected urethral stricture, which is most often a result of trauma, surgery, prolonged catheterisation or radiation therapy. Those men with poor urinary stream, not thought to be a result of prostatomegaly, may be candidates for this test. Referral is usually from a specialist urologist or on their advice.
A urethrogram is a contrast study of the urethra under fluoroscopic control. This is done by placing a catheter into the urethral meatus, expanding the balloon gently to form a seal and running a small volume of contrast into the urethra under image control. Frequently, a voiding study is needed and is carried out by filling the bladder after catheterisation, removing the catheter and having the patient void under imaging control with spot films.
Urethrograms are usually carried out after specialist referral. Some urologists may agree to a urethrogram being carried out after a telephone consultation.
Urinary infections should be treated before a urethrogram being carried out. In patients with recurrent urinary tract infections, antibiotic prophylaxis should be considered. The study can be carried out towards the end of a course of antibiotic treatment for urinary tract infection.
There are really no absolute contraindications. Because the contrast is not injected intravenously, the risk of reaction is minimal. Given the theoretical risk of contrast intravasation with urethral mucosal damage, patients with a history of moderate or severe contrast reaction should be premedicated or an alternative contrast used.
Severe urinary tract infection should be treated before a urethrogram is carried out, unless there are exceptional circumstances; for example, the possibility of traumatic catheterisation, or the failure of catheterisation in a patient who needs to be catheterised as part of management.
Patients may feel embarrassed by the procedure and therefore unwilling to undergo it. However, this can usually be overcome by adequate explanation and a sympathetic attitude of staff present in the room during the procedure.
Mild or minor haematuria after catheterisation is common, short lived and rarely a problem if patients are warned to expect it.
Infection after catheterisation may require investigation and treatment. It is rare if the procedure is carried out with the appropriate sterile technique.
In the setting of acute urethral injury, an attempted urethrography may result in swelling or oedema, and may cause subsequent urinary retention.
Magnetic resonance imaging is the preferred procedure for examining the female urethra, where the study is usually for determining the presence of a diverticulum. In the male, the functional information about flow limitation produced by strictures is better shown by a urethrogram.
There has been some recent interest in carrying out studies of the urethra using ultrasound. This still requires distension of the urethra with jelly or fluid, so is still as invasive in that respect.
Voiding studies are difficult and need to be carried out by someone who is experienced in this study.
Urethrograms for trauma can be carried out in the acute situation to confirm the presence of a rupture or partial rupture of the urethra. An ascending study is usually all that is needed. The study can be delayed for some weeks and the patient managed with a suprapubic catheter throughout the acute injury and recovery phase, and an elective repair carried out at an interval post-injury. A urethrogram is often useful for operative planning at this stage.
Page last modified on 26/7/2017.
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