sténose urétrale

Diagnosis of urethral stricture

The narrowing of the male urethra is often overlooked or diagnosed late because the signs and symptoms that suggest the existence common to other obstructive diseases of the urinary tract and the most commonly used imaging explorations do not explore the urethra properly.

But it is important to bear this diagnosis early so as to deal in the best conditions the narrowing of the urethra and thus prevent it from damaging the urinary tract.

Note: The terminology regarding urethral anatomy is defined in the article on this subject.

 

Positive diagnosis

The diagnosis is based mainly on the examination, uroflowmetry, endoscopic urethral canal and specific imaging tests.

 

1.The questioning

It is mostly based on the collection by the urologist of signs (objectives) and symptoms (subjective) which the patient complains about.

Among them are particularly suggestive:

– Symptoms resulting obstruction: weakening of the urinary stream represented by dysuria, bladder emptying disorders

– Voiding inflammatory disorders of the lower urinary tract such as increasing the number of urination (urinary frequency) and the imperative need to urinate;

– Abscesses in scholarship or perineum or urethral discharge

– Ejaculation without pressure or dribbling.

It is important to look at the patient history that could favor the occurrence of urethral stricture as trauma with pelvic fracture or fall astride or especially endoscopic surgical procedures have focused on the lower urinary tract or the concept of retrograde maneuvers on the urethra (sometimes traumatic catheterization).

All these signs and symptoms are described in more detail in a specific section.

 

2.The clinical exam

It includes systematically:

  • The examination of the abdomen and lower back graves:the presence of a retention bladder after urination can be evoked by palpation of a distended bladder or the percussion of a suprapubic dullness. It is confirmed by a échoscopie or a bladder scan.
  • The Examination of the external genitalia, including the urethral meatus. Palpation of the urethral bulb in the perineum can rarely show induration related infectious phenomena.
  • The digital rectal examination
  • It is interesting to see the patient urinate to appreciate the character of his urination and appearance of urine (clear or turbid, filamentous, bloody …). The analysis of urination is best achieved by flow measurement which provides quantitative and comparative data for review to another.

 

3.The biological exams

They bring little to the diagnosis of urethral stricture. It will be necessary to seek a urine infection by achieving a cytobacteriological urinalysis (urine culture) and to assess renal function by studying the creatinine clearance by the MDRD formula.

 

4. The flow measurements and endoscopy

– The flow measurement used to assess the characteristics of urination. This is a very simple examination, the urologist performed the firm or the radiologist, noninvasive. The patient is asked to come to a full bladder and urinate in the meter. A curve is obtained whose appearance can learn about the absence (bell curve) or, conversely, the existence of a dysuria (flat curve) and collected figures characterizing urination, especially urinated volume, flow maximum micturition and the average flow rate expressed in milliliters per second, and the duration of urination.

The maximum flow rate reflecting the dysuria is less than 10 ml / second.

The flow measurement is not interpretable if the review included a urination at least 150 ml.

This simple test can be repeated during various consultations and allow for useful comparisons to assess changes in the patient’s condition.

 

débimétrie

 

Endoscopy of the urethral canal (urethroscopy) performed using a flexible endoscope and end (urinary endoscope) inserted through the urethra and the meatus under local anesthesia allows an immediate diagnosis when the progression of the device to the bladder is prevented by the presence of narrowing it can not cross. Endoscopy of the urethra, however, information on only the distal end of the stenosis and its tight or not. She does not know the length of this narrowing, or the state of the urethra and bladder upstream narrowing and this data is important to ask the indications for treatment.

 

5. The imaging tests

This is obscuring the urethra and this can be achieved in the direction of voiding flow (antegrade explorations) or in the opposite direction of that flow (retrograde explorations).

The antegrade opacification is achieved when the patient’s bladder is full of contrast, asking her to urinate while standing and taking X-rays of his urination ¾ to fully extend the urethra.

Information is thus obtained on:

  • The condition of the bladder form, capacity, irregularity of its walls, the presence of diverticula, research lesions (stones, tumors), quality of voiding the ultimate postvoid cliché;
  • The opening of the bladder neck;
  • The channel of the urethra itself with the characteristics of shrinkage, including its headquarters, where there is a channel of class disparity, and its impact in terms of the importance of the expansion of the urethra portion located above the stenosis;

An imagery monitoring urination, obtained by pinching the glans to close the urethra to its most distal portion, specifies the length of the stenosis, its appearance and if it is low or very tight.

Imagerie cliché en miction contrariée

 

The opacification urethra retrograde is obtained by injecting the contrast medium by the urethral meatus.
Imagerie opacification rétrograde de l’urèthre

Imaging tests for studying the urethra are:

  1. The intravenous urography (IVU) is an examination that was once widely used in urology and has today only rare indications. The opacification of the urinary tract is obtained by injecting intravenously an iodinated contrast agent (in a patient having no iodine allergy). It allows the study of the upper urinary tract, and the lower urinary tract, especially during the voiding study that includes taking pre-voiding bladder full shots, one or more shots per- made during voiding the patient’s urination after asking him to urinate, and a voiding post cliché to appreciate the importance of residual urine.
  2. The suprapubic cystography with uréthrographie down: it achieves the same study of lower urinary tract than that achieved by the time of voiding intravenous urography. The opacification of the bladder is obtained by asking the patient to come to the exam with very full of urine bladder, allowing the puncture above the pubic bone with a fine needle through which the contrast medium is injected directly into the bladder.
  3. Retrograde urethro-cystograpie and voiding (uCRM) where the filling of the bladder is achieved by injecting contrast material at the urethral meatus, against the current. It has two phases, allowing optimal study of the urethra retrograde urétrographie, followed by downward urethrovaginal cystographie which is the same voiding study that achieved during intravenous pyelogram. It is important before the completion of this review to ensure that the urine is sterile well by practicing a urine culture.
    Large hematoma scholarships
    Large hematoma scholarships after traumatic rupture of the urethra consecutive bulbar a fall astride
Volumineux hématome des bourses

Large hematoma after traumatic rupture of the bulbar urethra in a row to fall astride

Ultrasound and imaging tests sectional (CT and MRI) are of little use in the assessment of urethral strictures. The latter two tests including MRI are useful especially in cases of post-traumatic stenosis to assess the damage to the membranous urethra and the membranous bulb junction.

This review also analyze the spongy lesions periurethral often causes relapses.

 

Differential diagnosis

The urologist must confirm the diagnosis of urethral stenosis and eliminate other causes of dysuria and obstruction of low male urinary system including:

– A benign prostatic hyperplasia;

– A prostate cancer;

– Chronic prostatitis;

– Illness or sclerosis of the bladder neck;

– Neurogenic bladder.

 

Some bibliographical elements:

 

In English

http://www.urethralcenter.it/English_version/pagine/diagnosi.html

http://www.mayoclinic.org/diseases-conditions/urethral-stricture/care-at-mayo-clinic/tests-diagnosis/con-20037057

http://www.ejradiology.com/article/S0720-048X(09)00368-4/abstract

http://nyulangone.org/conditions/urethral-stricture/diagnosis

http://www.urethralsurgery.com/urethral_stricture.asp

http://www.uroinfo.ca/brochures_kidney_fr/renalColic_fr.html

In French

http://www.dematice.org/ressources/DCEM2/urologie/D2_uro_008/co/document.pdf

http://pe.sfrnet.org/Data/ModuleConsultationPoster/pdf/2009/1/2c29600e-9699-4740-908c-a302e07accb5.pdf

http://www.medecine-cours.com/2013/03/retrecissement-de-luretere-diagnostic.html

http://urofrance.org/science-et-recherche/base-bibliographique/article/html/lurologie-par-ses-images-partie-i-chapitres-ii-iii-et-iv-traumatismes-vesicaux-de-lurethre.html

http://urofrance.org/nc/lurologie-grandpublic/fiches-patient/resultats-de-la-recherche/html/ureteroscopie.html