Comparing The Four Imaging Examinations In Diagnosis Of Traumatic Posterior Urehtral Stricture

Purpose:There are many methods in treatment of posterior urethral stricture,but the results are different with the posterior urethral injury and the degree of urethral stricture.It is a long time to recovery after operation of posterior urethral stricture,furthermore, it is more easy leading to complications such as restenosis,urethral skin fistula, and so on. It is the key of formulating operational plans and success with perfect diagnosis and patient’s condition evaluation before operations.Conventional imaging examination is urethrography including voiding and retrograde urethrography. In recent years, there are a few report of type-B ultrasound imaging of urethra, but most of them are restricted of anterior urethra.CT urethrography, as just one paper reported, is just applied in voiding urethrography. MR urethrrography also restricted in measurement of the length of urethral stricture and other findings. In our study, we compared the four examinations in diagnosis of traumatic posterior urehtral stricture, so that we could have better known of the posterior urethral stricture and had better operational plans with confidence.Object and methods:There were twenty one male patients of traumatic posterior urethral stricture,who`s age were from 18 to 65 years,mean 32.3 yeas.All the patients had known the fact of the checks and signed the consent papers. They all had injuried more than six months and had suprapubic cystostomy more than one week before examinations.All patients had the four examinations as following.the first check is conventional urethrograhy including voiding and retrograde urethrography, measuring the length of urethral stricture,check time, price and other fingdings.The second is sonourethrography(transrectal ultrasonography):injected the normal saline from external urethral orifice into the urethra,as the normal saline passed into the urethra,and the patients try hard to voiding,we measuring the length of urethral stricture,check time, price and other fingdings such as fistula,stone,diverticulum and so on.The third is CTU(64-MDCT urethrograhpy): directly infused 250–400 ml of diluted acetrizoic acid via suprapubic tube into the bladder and placed a catheter at the anterior urethra, injected 2–3 ml normal sodium into the balloon to avoid the catheter slipping off, and dropped the diluted acetrizoic acid into the anterior urethra.We performed CT after the patient started to void and the acetrizoic acid was stopped dropping automatically into the anterior urethra. Data acquisition was craniocaudad and resulted in about 300 transverse images for each scan. The transverse thin sections were transferred to a workstation with manufacturer-provided software that allows generation of 2D maximum intensity projection, 2D multiplanar reconstruction, and 3D shaded-surface display. The data keeped in the compact disk and were three-dimensional reconstructed in the computer. Measuring the length of urethral stricture, check time, price and other complications. At the same time,the data were usd to sham operated by rapid prototyping.The last is MR urethrography:before examination, injected the sterile coupling medium into anterior urethra, measuring the length of urethral stricture,check time, price and other fingdings such as degree of scar,fistula,diverticulum and so on.ResultsThe check time is (9.00±1.73) min, (7.42±1.47) min, (10.00±1.78) min and (22.43±1.66) min;conventional urethrograhy, sonourethrography,64-MDCT urethrography and MR urethrography;respectively.the check price basic number is one, one, three and four; conventional urethrograhy, sonourethrography,64-MDCT urethrography and MR urethrography;respectively. measuring the length of urethral stricture is(2.12±0.91)cm, (1.99±0.99)cm, (1.91±0.74)cm, (1.88±0.72)cm and (1.90±0.73)cm;conventional urethrograhy, sonourethrography,64-MDCT urethrography , MR urethrography and operation; respectively. Twenty one patients` data of CT urethrography are stored and input the computer, the 3D reconstruction and rapid prototyping were made.Conclusions:It is very important of imaging examination for traumatic posterior urethral stricture.conventional urethrography including voiding and retrograde urethrography is the basic and most commonly examination.it costs less and handle simple; sonourethrography is conveniently for handle, real-time imaging, no radiation exposure, but the results have some error and the operator need good skill. The benefits of CT urethrography include production of both transverse and 3D images of urinary tract abnormalities without magnication or distortion depiction of extraluminal anatomic landmarks and good patient compliance.furthermore, those images may be useful to guide the surgery by rapid prototyping, but the patients may be had more radiation exposure and cost more than conventional urethrography or sonourethrography. The benefits of MR urethrography include perfectly showing the posterior urethral stricture and it`s surrounding tissue and no radiation exposure, but it`s limited of steel pate in lower abdominal region, longerst examinational time and expensive.If we have some anxiety or unknown after conventional urethrography,we would chose or CT or MR urethrography, some time, sonourethrography is the second chioce.So that, we can understand enough and can provide extra guidance for treatment planning.