Histology of the urethral plate: implications for hypospadias repair

Reconstructing forked corpus spongiosum to correct glans droop in distal/midshaft hypospadias repair

Purpose

We reviewed our experience and efficacy of reconstruction of a forked corpus spongiosum (FCS) to correct glans droop in distal/midshaft hypospadias repair.

Methods

Eighty-five consecutive patients who underwent distal/midshaft hypospadias repair by the same surgeon in our center from October 2015 to June 2018 were retrospectively analyzed. All cases were accompanied by different degrees of glans droop, which we corrected by cutting off and reconstructing the FCS along the plate. We recorded the degrees of glans droop, development of the FCS, and postoperative complications including residual chordee, fistula, diverticulum, glans dehiscence, meatus stenosis, and urethral stricture.

Results

The follow-up period ranged from 5 to 37 months (mean, 19.7 months). Two patients (2.3%) developed a coronal fistula and underwent a second repair. Two patients (2.3%) developed a mild urethral diverticulum and underwent continued observation. One patient (1.2%) developed a meatus stenosis that resolved after 1 month of meatus expansion combined with external mometasone furoate. No patients developed postoperative residual chordee or urethral stricture.

Conclusions

The degree of glans droop is closely associated with the development of an FCS. Reconstructing the FCS to correct the glans droop can yield satisfactory outcomes and should be popularized in distal/midshaft hypospadias repair.

Application and efficacy of reconstructing forked corpus spongiosum in distal/midshaft hypospadias repair

We reviewed our experience in reconstructing forked corpus spongiosum (FCS) in distal/midshaft hypospadias repair and analyzed the efficacy of this surgical technique. From August 2013 to December 2018, 137 consecutive cases of distal/midshaft hypospadias operated by the same surgeon in Urology Department, Children's Hospital of Fudan University (Shanghai, China), were retrospectively analyzed. Sixty-four patients who underwent routine tubularized incised plate (TIP) or onlay island flap (ONLAY) surgery were included in the nonreconstructing group, and 73 patients who underwent reconstructing FCS during TIP or ONLAY surgery were included as the reconstructing group. Thirty-eight cases underwent TIP, and 26 underwent ONLAY in the nonreconstructing group, with a median follow-up of 44 (range: 30–70) months. Twenty-seven cases underwent TIP, and 46 underwent ONLAY in the reconstructing group, with a median follow-up of 15 (range: 6–27) months. In the nonreconstructing/reconstructing groups, the mean age at the time of surgery was 37.55 (standard deviation [s.d.]: 29.65)/35.23 (s.d.: 31.27) months, the mean operation duration was 91.95 (s.d.: 12.17)/93.84 (s.d.: 14.91) min, the mean neourethral length was 1.88 (s.d.: 0.53)/1.94 (s.d.: 0.53) cm, and the mean glans width was 11.83 (s.d.: 1.32)/11.56 (s.d.: 1.83) mm. Twelve (18.8%)/5 (6.8%) postoperative complications occurred in the nonreconstructing/reconstructing groups. These included fistula (5/2), glans dehiscence (3/0), diverticulum (1/2), residual chordee (3/0), and meatus stenosis (0/1) in each group. There was a significant difference in the overall rate of complications (P = 0.035). These results indicate that the technique of reconstructing FCS provides excellent outcomes with fewer complications in distal/midshaft hypospadias repair.

The impact of COL1A1 and COL6A1 expression on hypospadias and penile curvature severity

BACKGROUND

Hypospadias, the most frequent congenital male external genitalia abnormality, is usually associated with curvature of the ventral penis, i.e. chordee. Abnormality of darto tissue has been suggested as the pathophysiology of chordees. Collagen is one of the most abundant fibrous proteins within the extracellular matrix. In this study, we determined the expression of collagen 1 (COL1A1) and COL6A1 in patients with hypospadias and associated them with the severity of penile curvature.

METHODS

We included 60 children < 18 years old, consisting of 20 distal hypospadias, 20 proximal hypospadias patients, and 20 controls in our institution from 2017 - 2020. The expression of COL1A1 and COL6A1 in darto tissue was determined by reverse-transcriptase polymerase chain reaction (qPCR). The penile curvature severity was classified as mild (< 30 degrees), moderate (30-60 degrees), and severe (> 60 degrees).

RESULTS

qPCR showed that COL1A1 and COL6A1 expression was significantly downregulated in the distal (0.88 (0.38-2.53) and 0.54 (0.16-4.35), respectively) and proximal 0.76 (0.33-2.57) and 0.57 (0.18-1.38), respectively) hypospadias groups compared to controls (1.85 (0.24-4.61) and 0.93 (0.17-4.06), respectively) with p-values of 0.024 and 0.018, respectively. Furthermore, there was a moderate correlation between COL1A1 and COL6A1 expression (r = 0.458, p < 0.0001). Interestingly, COL1A1 and COL6A1 were also significantly downregulated in the moderate and severe chordee groups compared to the mild chordee groups, with p-values of 0.003 and 0.037, respectively.

CONCLUSIONS

Aberrant COL1A1 and COL6A1 expression might affect abnormalities in darto tissue and penile curvature severity in hypospadias patients.

Megameatus intact prepuce treated with urethral plate-preserving surgery: a retrospective study of an unusual hypospadias variant

BACKGROUND

Megameatus intact prepuce (MIP) is a unique variant of hypospadias and is a clinically rare condition. Due to the anatomical characteristics of the MIP hypospadias variant presenting a unique challenge to surgeons, no single urethroplasty method provides a universal solution for all patients. The purpose of this study was to evaluate the outcomes of hypospadias after MIP repair by urethral plate-preserving urethroplasty.

METHODS

A retrospective study was performed on 25 coronal or distal MIP patients, with a median age of 8, with most deficiencies being discovered during their first hospital visit for phimosis. Correction with urethroplasty was performed for all patients; 5 underwent the Mathieu procedure, 13 underwent the tubularized incised plate (TIP) procedure, and 7 underwent the Duplay procedure. The 25 patients were followed up for 6 to 36 months to evaluate the surgical outcomes.

RESULTS

There were no significant differences in intraoperative bleeding, hospital stays, postoperative analgesia rate, and cure rate among the three surgical procedures. The operative time for the Mathieu procedure was longer than that for the TIP and Duplay procedures, which did not differ. Complications occurred in 4 of the 25 patients (16.0%), and the overall complication-free survival rate at 1 year after surgery was 80.5%. The age at the time of surgery, urethral plate width, urethroplasty length, surgical procedures, or meatal location (coronal or distal penis) were not independently predictive of complications.

CONCLUSIONS

The clinical manifestations of MIP are often concealed and then accidentally discovered during hospital visits for phimosis; thus, the actual incidence of MIP might be higher. The urethral plate should be preserved during MIP-correcting treatment, especially for coronal or distal MIP. The same satisfactory outcomes can be obtained with Mathieu, TIP, or Duplay urethroplasty.

Pedicled preputial island flap for double functions in hypospadias surgery

OBJECTIVE

To use the prepuce for double functions one as a second layer for the neourethra to decrease the incidence of urethrocutaneous fistula and the second as a skin covering for the ventral aspect of the penis.

MATERIAL AND METHODS

From January 2013 to December 2016, 37 cases of hypospadias with mild to moderate chordee were included in this study. The cases with ventral penile skin defect were managed by tubularized incised plate urethroplasty (TIPU) using pedicled preputial flap. Recurrent cases, cases with severe chordee which necessitated division of the urethral plate, and cases with penoscrotal hypospadias were excluded from this study.

RESULTS

Thirty-seven cases of hypospadias aged 9-60 months with a mean age of 24.8 months were included in this study. Coronal (n= 9 cases; 24.3%), distal penile (n=11; 29.9%), and midpenile hypospadias (n= 17; 45.9%) were detected in respective number of patients. Postoperative complications consisted of external meatal stenosis (n=2; 8.1%), and one case with urethrocutaneous fistula. Skin necrosis was not reported in this study. Follow-up visits were performed at 1, 3 and 6 months which showed good cosmetic appearance that was accepted by their parents.

CONCLUSION

This technique was beneficial in decreasing the rate of skin necrosis, as it keeps the blood supply to the preputial skin intact, and decreases the incidence of urethrocutaneous fistula.

The contemporary role of 1 vs. 2-stage repair for proximal hypospadias

This review discusses the most commonly employed techniques in the repair of proximal hypospadias, highlighting the advantages and disadvantages of single versus staged surgical techniques. Hypospadias can have a spectrum of severity with a urethral meatus ranging from the perineum to the glans. Associated abnormalities are commonly found with proximal hypospadias and encompass a large spectrum, including ventral curvature (VC) up to 50 degrees or more, ventral skin deficiency, a flattened glans, penile torsion and penoscrotal transposition. Our contemporary understanding of hypospadiology is comprised of a foundation built by experts who have described a number of techniques and their outcomes, combined with survey data detailing practice patterns. The two largest components of hypospadias repair include repair of VC and urethroplasty. VC greater than 20 degrees is considered clinically relevant to warrant surgical correction. To repair VC, the penis is first degloved-a procedure that may reduce or remove curvature by itself in some cases. Residual curvature is then repaired with dorsal plication techniques, transection of the urethral plate, and/or ventral lengthening techniques. Urethroplasty takes the form of 1- or 2-stage repairs. One-stage options include the tubularized incised urethroplasty (TIP) or various graft or flap-based techniques. Two-stage options also include grafts or flaps, including oral mucosal and preputial skin grafting. One stage repairs are an attractive option in that they may reduce cost, hospital stay, anesthetic risks, and time to the final result. The downside is that these repairs require mastery of multiple techniques may be more complex, and-depending on technique-have higher complication rates. Two-stage repairs are preferred by the majority of surveyed hypospadiologists. The 2-stage repair is versatile and has satisfactory outcomes, but necessitates a second procedure. Given the lack of clear high-quality evidence supporting the superiority of one approach over the others, hypospadiologists should develop their own algorithm, which gives them the best outcomes.

Management of adults with prior failed hypospadias surgery

Hypospadias is one of the most prevalent anomalies of the male genitalia. Contemporary hypospadias repair is very successful, but patients that have the surgery fail often require multiple surgeries throughout their life. Complications from failed hypospadias repairs have a significant impact on patients both psychologically and physically. Failed hypospadias repair encompasses a spectrum of problems that include hypospadias recurrence with an ectopic meatus, urethral fistula, urethral stricture, and ventral penile curvature. Repairs of hypospadias complications can be challenging due to the poor quality of surrounding tissue from disruption of normal vasculature in the re-operative field associated with the underlying disorder. One of the most challenging issues is dealing with urethral strictures. There have been multiple methods described at repairs of these in both a single stage and multiple staged procedures. Particular attention has been directed towards applications of grafts due to worse outcomes with flaps. Buccal mucosa has emerged as the leading graft material in staged repairs. When counseling patients with failed hypospadias it is important to discuss the expected outcome as repairs directed towards a terminally positioned meatus with a straight phallus may require multiple surgeries due to post-operative complications as well as the necessity of proceeding in a staged approach.

Impact of penile degloving and proximal ventral dissection on curvature correction in children with proximal hypospadias

INTRODUCTION

Penile degloving is an important step in orthoplasty. Although its role in correcting mild curvature in distal and midshaft hypospadias has been previously reported, its impact on ventral curvature (VC) correction in proximal defects warrants further investigation. Therefore, we sought to document the effect of degloving and proximal urethral dissection on VC correction in children with proximal hypospadias.

METHODS

We retrospectively reviewed the records of 137 patients who underwent proximal hypospadias repair between 1998 and 2006. VC, defined as mild (<30%), moderate (30%-45%), and severe (>45%), was recorded before penile degloving and after erection test. Percent improvement in VC and need for further treatment (beyond degloving and proximal dissection) based on preoperative degree of curvature were assessed. ANOVA test was used to compare improvement among the 3 groups.

RESULTS

Mean age at repair was 14 months (range: 6-24). Penile degloving associated with proximal urethral dissection when necessary was responsible for the improvement in the degree of curvature in 7 of 9 (77%) patients with mild VC, 23 of 44 (52%) with moderate and 35 of 84 (40%) with severe VC. Additionally, degloving alone was sufficient for VC correction in 7 of 9 (77%) mild cases, 14 of 44 (30%) moderate and only 2 of 84 (2%) severe cases. The difference among these 3 groups was statistically significant (p < 0.001).

CONCLUSIONS

Penile degloving alone can correct VC. The percentage of improvement depends on the preoperative degree of curvature, with severe VC cases showing the least improvement.

Distal extension of the midline urethral-plate incision in the Snodgrass hypospadias repair: An objective assessment of the functional and cosmetic outcomes

Objectives

To objectively assess the functional and cosmetic outcomes of a modified tubularised incised-plate (TIP) urethroplasty (Snodgrass) technique, with particular attention to the uroflowmetry study and Hypospadias Objective Scoring Evaluation (HOSE) score.

Patients and methods

In a prospective case-series study, 43 consecutive patients with primary distal hypospadias were evaluated. The modified Snodgrass technique included an extension of the midline relaxing incision of the urethral plate from within the hypospadiac meatus to the very tip of the glans. The neourethra was tubularised starting at the neomeatus and proceeding proximally. The neourethra was covered with either a single or double dartos flap. In toilet-trained boys, at least 3 months after surgery, the flow pattern, maximum (Q_max), and mean urinary flow rate (Q_ave) were recorded, and the results plotted against a recently published flow-rate nomogram from normal children. The postvoid residual urine volume was measured using ultrasonography. The cosmetic outcome was assessed using the HOSE system.

Results

The native meatus was coronal in 11 (26%), subcoronal in 23 (53%) and distal penile in nine (21%) of the patients. The median (range) age was 4.2 (0.5–14) years. The neourethra was covered by a single dorsal dartos flap in 25 and a double dartos flap in 18 patients. At a median (range) follow-up of 6 (3–24) months, the uroflowmetry findings in 26 uncomplicated toilet-trained boys with a median (range) age of 5.2 (3.3–14) years showed an abnormal Q_max below the fifth percentile in four (15%), with the Q_ave above the fifth percentile in all. The flow pattern was bell-shaped in nine boys (35%), interrupted/intermittent in five (19%), slightly flattened in 10 (39%) and a plateau in two (8%). A vertical slit-like meatus located at the distal glans was created in 39 (91%) boys, and at the proximal glans in four (9%). The urinary stream was single and straight in 39 and angled in four patients. A straight erection was observed in 42 (98%) boys. Four patients had preoperative mild penile torsion of <45°, that was corrected by surgery. The mean (SD, range) HOSE score was 15.8 (0.6, 13–16). Two patients had a small, single subcoronal fistula.

Conclusion

Extending the midline urethral plate-incision in the modified Snodgrass repair to the apical part of the glans can be done safely with a high rate of locating the neomeatus at the glans tip, with no resultant meatal stenosis. The functional and cosmetic results of the procedure are good, but long-term data and comparative studies are required to confirm these results.

Utilization of urethral plate in hypospadias surgery

Purpose

Recognition the urethral plate comprises tissues that normally should have created the urethra was an important milestone in hypospadias surgery, giving rise to new operative repairs - most notably the tubularized incised plate technique. This article reviews the current state of the art for hypospadias repair using tubularized, incised plate (TIP).

Materials and Methods

Personal experience and literature reports were reviewed to summarize use of TIP urethroplasty for distal, proximal, and re-operative hypospadias repairs.

Results

The TIP can be used to correct all distal and most proximal hypospadias. The major contraindication is ventral curvature that leads to urethral plate transection for straightening, which is only necessary in some proximal cases. Reoperations can also be performed using TIP provided the urethral plate has been maintained and is not grossly scarred. Complication rates are comparable to previously used techniques, while cosmetic appearance after TIP is considered superior to other available procedures.

Conclusions

Recognition of the urethral plate and its incorporation into the neourethra has revolutionized hypospadias repair. The most commonly used operative procedure today is TIP.

The comparison of Belt-Fuqua and "TIPU" techniques in proximal penile hypospadias cases: retrospective analysis of 65 cases

OBJECTIVE

We have compared our success and complication rates using the single-step "TIPU" (tubularized incised plate urethroplasty) and two-step Belt-Fuqua techniques in patients with proximal penile hypospadias.

PATIENTS AND METHODS

Sixty-five patients with proximal penile hypospadias were operated on in our clinic between 1998 and 2008: 31 by the "TIPU" technique and 34 by the Belt-Fuqua technique. The correction of the chordee was accomplished with dorsal plication and corporal body grafting in 18 patients in the "TIPU" group and at the first stage in all patients in the Belt-Fuqua group.

RESULTS

The mean age of the patients was 6.2 years in the "TIPU" group and 6.6 years in the Belt-Fuqua group. The mean follow-up duration was 9.2 and 7.9 months, respectively. The overall complication rate was 22.6% in the "TIPU" group and 11.8% in the Belt-Fuqua group. In both groups, the cosmetic appearance of a natural vertical slit glanular meatus situated at the normal position on the glans was achieved.

CONCLUSION

The two-step Belt-Fuqua technique is accepted as a good alternative treatment modality because of low complication rates and good results in selected cases with proximal penile hypospadias.

Tubularized incised plate urethroplasty for distal hypospadias: A literature review

The tubularized incised plate (TIP) urethroplasty or Snodgrass procedure has gained worldwide acceptance for distal hypospadias repair due to its low complication rate, good cosmetic result, and technical simplicity. As a result, several articles have been published concerning various aspects and subtle variations of this procedure. The aim of this review is to critically and systematically analyze the published complication rates of TIP repair for distal hypospadias in children. We also reviewed the surgical modifications that have been introduced to the original technique and discussed the potential impact on the final outcome of the Snodgrass procedure.

[Correction of hypospadias by the Snodgrass method. Indications and results]

Tubularisation of the urethral plate with a medial incision was popularized by Snodgrass in the late 1990s. Since then this procedure has emerged throughout the world as the method of choice for correction of primary hypospadias. The procedure is applied as the technique of choice for primary correction of hypospadias, regardless of the level of the hypospadic meatus and the width of the original urethral plate, and is also used in various situations for secondary hypospadias surgery.. The complication rate is about 5-10 % in primary cases and between 10% and 20% in revision surgery for hypospadias repair.

Short-term catheterization after TIP repair in distal hypospadias: who are the best candidates?

Over the last decade, tubularized incised plate (TIP) urethroplasty has become the first choice of surgical technique in patients with distal hypospadias. Despite the excellent cosmetic and functional results, prolonged catheterization (7-14 days) remains the main disadvantage of the TIP repair. In this study, we investigated the outcomes of the short-term catheterization in children with distal hypospadias in order to elucidate any relationship between the length of catheterization and the patients' age, meatal localization and postoperative complication rates. The charts of 183 patients who underwent TIP repair for distal hypospadias in two different centers were reviewed retrospectively. Patients were grouped based on their catheter removal time (before 24 h vs. after 24 h) and the toilet status of children (toilet-trained vs. in-diaper). Children who had at least 6 months of follow-up and regular office visits were included in the study group, and the results were compared to the literature as well as the subgroups were also evaluated in terms of complications and catheterization period. A total of 128 patients with 40.4 months of the mean age (6-180 months) and 22.7 months of the follow-up (6-49 months) were included in the study. For the group 1 patients (n = 99) in whom the urethral catheter was removed before 24 h, the mean age and follow-up were 33.4 months (6-150 months) and 22.3 months (6-48 months), respectively. The catheters of group 2 patients (n = 29) were removed after 24 h, and their mean age and follow-up were 64.4 months (6-180 months) and 24.2 months (6-49 months), respectively. The group 2 patients were significantly older than those of group 1 (P < 0.05). The complications, such as fistula, meatal stenosis, tube dehiscence and buried penis, were seen in 11.1% of the group 1 and 13.8% of the group 2 (11.7% in overall), showing no statistically significant difference. On the other hand, 44% of the patients (n = 56) were toilet-trained at time of surgery. Although the mean age (79 months vs. 10.4 months) and the catheter removal time (64.3% vs. 87.5% before 24 h) of this group were significantly longer than the patients in diaper (P < 0.05), no significant difference was determined in terms of complication (14.2% vs. 9.7%). TIP repair with short-term catheterization has similar outcomes to the patients who conventionally carry their stent 7-14 days. The meatal position and the toileting status of the patients are not important in the use and length of catheterization.

Results of dorsal midline plication in children with penile curvature and hypospadias

OBJECTIVES

To present our initial results using dorsal midline (12-o'clock position) plication in children with penile curvature and hypospadias.

METHODS

Twenty-five children with hypospadias and ventral curvature confirmed after artificial erection underwent dorsal midline plication and hypospadias repair. Ventral curvature was corrected by making a 5 to 10-mm-long vertical incision through the tunica albuginea at the dorsal midline and approximating the outer edges of the incision with a monofilament polydioxanone stitch.

RESULTS

One plication suture was needed in 15 patients. In 8 patients with mid-shaft hypospadias and 2 with proximal penile hypospadias, two and three sutures were needed, respectively. In none of the patients was division of the urethral plate needed, except for one with proximal hypospadias. No complications were encountered during a mean follow-up of 9 months (range 5 to 34).

CONCLUSIONS

We believe that most cases of penile curvature with hypospadias can be corrected using dorsal midline plication of the tunica albuginea. Although long-term follow-up is necessary after puberty to confirm any erectile or sensory advantage, this approach might be considered whenever plication is to be performed.

Biochemical analysis of urethral collagen content after tubularized incised plate urethroplasty: an experimental study in rabbits

The aim of the present study was the biochemical analysis of tissue hydroxyproline levels in incised urethral plates in order to show the total collagen content after the Snodgrass operation in the hypospadiac rabbit model. The study comprised 21 male New Zealand rabbits, (2.2-2.4 kg). The animals were randomly allocated to three groups each containing seven rabbits as follows: group 1, the ventral urethra was completely excised and a model of hypospadias formed. A full-thickness incision was made on the distal dorsal urethra, a feeding tube was placed as an urethral catheter and both urethral wings were sutured ventrally. Group 2, inserting an iris knife into the urethra, the ventral wall was incised mimicking an urethrotome. Group 3 consisted of normal control rabbits to determine the basal tissue hydroxyproline level. A slight increase in the hydroxyproline level was observed in the ventral part of the urethral tissue compared to the dorsal part in both groups 1 and 2; however, these differences were not significant. After the Snodgrass operation in the rabbit model, no significant differences were observed in the hydroxyproline levels of the dorsal and ventral parts of the urethra or between these and of the controls. Further studies are required in order to determine the mechanism underlying urethral healing through normal re-epithelization without excess collagen deposition after incised urethral plate urethroplasty.