Post-Operative Imaging After Urethroplasty With Peri-catheter Retrograde Urethrography Or Trial of Voiding With Voiding Cysto-urethrography
Post-Operative Imaging After Urethroplasty With Peri-catheter Retrograde Urethrography Or Trial of Voiding With Voiding Cysto-urethrography
After a reconstructive procedure of the urethra, a transurethral catheter is usually left in
 place to allow adequate healing of the tissues without exposure to urine. After 7-21 days,
 depending on several variables (e.g. type of reconstruction, stricture etiology, …), removal
 of the transurethral catheter is foreseen. However, in order to do so, the clinician first
 wants to objectify whether the urethra has indeed healed sufficiently and therefore he/she
 can rely on early postoperative imaging.

 Up until today, there is no clear standard about when and how to do early postoperative
 imaging and current practices are mainly based on expert opinion and habit. Basically, two
 strategies can be found amongst different urethroplasty centers: peri-catheter retrograde
 urethrography (pcRUG) and voiding cysto-urethrography (VCUG). A pcRUG is performed by placing
 a small caliber tube (e.g. feeding tube 5 Fr) in the meatus urethrae of the patient, next to
 the transurethral catheter (which remains in place), and injecting contrast alongside the
 catheter. With a VCUG, contrast is injected through the transurethral catheter, up to the
 bladder. Thereafter, the catheter is removed and the patient is asked to urinate and thus to
 pass contrast through the urethra.

 The primary end-point of this study is to compare 'the rightful decision to maintain the
 catheter at the time of imaging' between pcRUG only and pcRUG followed by VCUG in a
 within-patient fashion.
After a reconstructive procedure of the urethra, a transurethral catheter is usually left in
 place to allow adequate healing of the tissues without exposure to urine. After 7-21 days,
 depending on several variables (e.g. type of reconstruction, stricture etiology, …), removal
 of the transurethral catheter is foreseen. However, in order to do so, the clinician first
 wants to objectify whether the urethra has indeed healed sufficiently and therefore he/she
 can rely on early postoperative imaging.

 Up until today, there is no clear standard about when and how to do early postoperative
 imaging and current practices are mainly based on expert opinion and habit. Basically, two
 strategies can be found amongst different urethroplasty centers: peri-catheter retrograde
 urethrography (pcRUG) and voiding cysto-urethrography (VCUG). A pcRUG is performed by placing
 a small caliber tube (e.g. feeding tube 5 Fr) in the meatus urethrae of the patient, next to
 the transurethral catheter (which remains in place), and injecting contrast alongside the
 catheter. With a VCUG, contrast is injected through the transurethral catheter, up to the
 bladder. Thereafter, the catheter is removed and the patient is asked to urinate and thus to
 pass contrast through the urethra.

 In both of the aforementioned imaging modalities, patients are installed similarly on the
 X-ray table and an antero-posterior X-ray image is made1. In patients with no or
 insignificant, wisp-like extravasation of contrast, the transurethral catheter can safely be
 removed. In case of significant contrast extravasation, as defined by Grossgold et al., the
 catheter is maintained or replaced for another week and one week later, imaging is repeated2.

 Both pcRUG and VCUG are not perfect and involve a number of flaws. The main issue with pcRUG
 is represented by the potential impact of several variables on the image: different levels of
 pressure in the urethra by different strength of injection, different calibers of tubes
 through which the contrast is injected, etc. As regards VCUG, an important amount of patients
 does not achieve to void while being on the X-ray table, which can lead to a long duration of
 the procedure or even no imaging at all. Another important problem is the fact that if the
 patient has a significant extravasation of contrast, the catheter needs to be replaced
 through the freshly reconstructed, and apparently still leaking, urethra. This may be
 difficult and is often bothersome for the patient.

 Given the drawbacks mentioned above, a combination of both techniques can be administered to
 overcome the flaws of each separate imaging modality and could as such be considered the
 standard of care in early postoperative imaging after urethroplasty. However, the combination
 of both techniques includes a higher exposure to radiation than one separate technique and
 one could wonder what the added value of VCUG after pcRUG is and whether or not this is worth
 the extra exposure to radiation. To date, there is no such data and a wide variability of
 strategies is used in the different urethroplasty practices worldwide.

 Against this background, the primary end-point of this study is to compare 'the rightful
 decision to maintain the catheter at the time of imaging' between pcRUG only and pcRUG
 followed by VCUG in a within-patient fashion.
Inclusion Criteria:

 -  Voluntarily signed written informed consent according to the rules of Good Clinical
 Practice (Declaration of Helsinki) and national regulations (Appendix B).

 -  Age ≥ 18 years.

 -  Male patient.

 -  Anterior urethral stricture disease (penile, bulbar, penobulbar and panurethral
 strictures are allowed).

 -  Procedure was ended with leaving a transurethral catheter in place with foreseen
 catheter removal and early postoperative imaging after x days.

 Exclusion Criteria:

 -  Absence of signed written informed consent (Appendix B).

 -  Age < 18 years.

 -  Female patients.

 -  Transgender patients.

 -  Posterior urethral stenosis

 -  Bladder neck reconstruction

 -  Patients in which no catheter has been left in place at the end of the procedure.

 -  Patients in which there is no need for early postoperative imaging, upon discretion of
 the treating clinician.