Commentary to ‘Urethral strictures following urethral plate and proximal urethral elevation during proximal TIP hypospadias repair’

Abstract

Mobilization of the urethral plate (UP) and native urethra is one of the manoeuvres that can be performed in order to straighten the penis while preserving UP continuity in severe hypospadias repair [1]. The authors of the present paper advocated it in conjunction with tubularized incised plate (TIP) urethroplasty in the recent past (see Ref. [2] in text). In the present series, they confirm that this combination is effective for penile straightening, as it allowed avoiding UP transection in some 25% of their cases with a 5% rate of recurrent curvature after a mean follow-up of 21 months. However, they also suggest that this combination is possibly hazardous and might predispose to stricture formation in the reconstructed urethra. The development of urethral strictures after TIP urethroplasty in patients undergoing UP/urethral mobilization is consistent with the concern that the latter might cause partial de-vascularization and ischemia in a UP that furthermore requires to be halved into two strips for tubularization. The 17% stricture rate is therefore a warning, but perhaps deserves some qualification. To begin with, this is a single-surgeon experience and, as the same authors acknowledge, other series of similar procedures did not include any such complication (see Refs. [3,4] in text). This cannot be attributed to the follow-up investigations performed, as the strictures reported in the present study were all symptomatic and none was diagnosed after a particular investigation in an otherwise asymptomatic patient. Moreover, it is worth noting that the stricture was very short, 1-mm to 3-mm long, in 3 of the 5 patients with this complication, and was associated with recurrent curvature due to contracture of the UP in only 1 case. In contrast, contracture of the UP was reported to be the cause of recurrent curvature in 2 of the 3 patients experiencing this complication in the group treated without mobilization. Yet, it is quite surprising that none of the patients undergoing mobilization developed any fistulas, as one would expect a higher rate of healing complications in the presence of ischemic tissues. According to the authors, technical refinements could account for the lower fistula rate in patients undergoing mobilization. This, however, points out that this study compares two series that were not contemporary, which is always a source of variability, and makes one wonder whether results in the patients undergoing TIP repair after UP/ urethral mobilization might improve as well with increasing experience. The latter might also include improvement in patient selection. Consistently, the authors suggest that TIP urethroplasty might still be an option in patients requiring mobilization of the UP, without mobilization of the native urethra or additional ventral lengthening procedures. Other possible criteria could be a UP wide enough after mobilization to make tubularization around a 10 Fr catheter possible (a 6 Fr was used in the present series), or a UP supported by thick spongiosum, especially if no injury to the latter and subsequent bleeding occurs during mobilization. Criteria for patient selection cannot be determined based on the data provided, but might account for the different results among series and deserve further enquiry. Finally, even fully accepting the authors’ conclusions, how can we incorporate them in our practice? Should we fully abandon UP mobilization, avoid combining it with a TIP repair, inlay graft the incised plate before tubularization, or always combine this maneuver with a flap urethroplasty?