[Free grafting of internal preputial lamina for penile divided nevus in children]

OBJECTIVE

To evaluate the effect of free grafting of internal preputial lamina in the treatment of penile divided nevus in children.

METHODS

This retrospective study included 5 children with penile divided nevus, 4 complicated by redundant prepuce and the other 1 by concealed penis, all treated by free grafting of internal preputial lamina from October 2015 to November 2017. The patients ranged in age from 6 years and 8 months to 10 years and 4 months, averaging 8 years and 6 months. The surgical procedure involved complete excision of the lesions underneath the foreskin with a safety margin of 2 mm, collection of healthy internal preputial lamina for free grafting onto the defected glans, and simultaneously circumcision or concealed penis correction. The removed tissue of the divided nevus was subjected to pathological examination. The patients were followed up for 4－29 (mean 18) months postoperatively.

RESULTS

All incisions healed primarily and the free grafts of internal preputial lamina survived well, similar to the glans in color and with a desirable appearance. The patients lost no protopathic sensibility of the glans and experienced no recurrence. Pathological examination confirmed 1 case of intradermal nevus and 4 cases of compound nevus.

CONCLUSIONS

Free grafting of internal preputial lamina is an ideal method for the treatment of penile divided nevus in children, with the advantages of easy graft collection, little color difference between the graft and surrounding skin, desirable external appearance, and definite clinical effect.

[Risk factors for the complications of primary hypospadias urethroplasty with the urethral plate reserved]

OBJECTIVE

To investigate the risk factors for the complications of urethroplasty in patients with primary hypospadias by postoperative follow-up observation.

METHODS

We retrospectively analyzed 110 cases of primary hypospadias repair performed from November 2010 to October 2015, including 70 cases of tubularized incised plate (TIP) urethroplasty and 40 cases of inlay internal preputial graft (IIPG) urethroplasty, all with the urethral plate reserved. We followed up the patients for 15.6－36 months, (27.3 ± 0.52) mo for those with and (26.9 ± 0.22) mo for those without complications. The mean age of the two groups of patients was (7.5 ± 0.2) and (7.0 ± 0.5) yr, respectively.

RESULTS

The follow-up data were collected from all the patients, 17 (15.5%) with and 93 (84.5%) without complications. The success rate of surgery was 84.5%. There were no statistically significant differences in the follow-up time and age between the two groups of patients (P >0.05). Single-factor analysis of variance showed significant differences between the complication and non-complication groups in the preoperative urethral opening (P <0.01), ventral penile curvature (P <0.01), and length of urethral defect (P = 0.04), while multiple linear regression analysis exhibited that only ventral curvature was associated with the postoperative complications of the patients (OR = 1.12, 95% CI: 1.06－1.19, P<0.01).

CONCLUSIONS

We chose single-stage urethroplasty with the urethral plate reserved for the treatment of primary hypospadias and achieved satisfactory outcomes. Ventral penile curvature is an independent risk factor for the complications of primary hypospadias, and a higher degree of curvature is associated with a higher incidnece of complications.

A novel technique for repair of mid-penile hypospadias using a preputial skin flap: results of 110 patients

BACKGROUND

Several techniques have been used to repair mid-penile hypospadias; however, high failure rates and major complications have been reported. In this study, we describe a novel technique using a well-vascularized flap of the inner and outer preputial skin.

METHODS

A total of 110 male children with hypospadias underwent repair by our technique between 2008 and 2015. The inclusion criteria were children with mid-penile or slightly more proximal hypospadias, with or without ventral chordae, and an intact prepuce of the cobra eyes variety. Recurrent cases, patients with other preputial types, and circumcised children were excluded from this study. The prepared flap was sutured in its natural longitudinal orientation to the created urethral plate strip to form a neo-urethra over a urethral catheter. Outcome measures included surgical success without the formation of a urethra-cutaneous fistula, no ischaemia of the flaps, glans dehiscence or infection and functional outcome and cosmetic appearance.

RESULTS

The median follow-up duration was 3.3 years. There were 63 cases of mid-penile hypospadias (57.3 %), and in 47 cases (42.7 %), the meatus was slightly more proximal. The age of the patients ranged from 1.1 to 8.0 years, with a mean age of 4.6 ± 1.2 years. Surgery was successful in 106 (96.4 %) cases. Minor complications occurred in 11 patients (10 %) and included oedema of glans in ten patients and bluish discoloration on the ventral aspect of the glans close to the suture line in three patients. All patients improved within 2 weeks after surgery. Long-term follow-up revealed a properly functioning urethra with a forward, projectile, single, compact, and rifled urinary stream of adequate calibre and cosmetically acceptable repair. No cases of meatal retraction, meatal stenosis, urethral stricture, or acquired urethral diverticulum occurred.

DISCUSSION

Our technique is different from the split prepuce in situ technique. We create a narrow strip of the urethral plate that facilitates glanular closure, and we use the inner and adjacent outer skin in a vertical manner to preserve excess skin for penile coverage. Prepuce is split at midline to preserve more preputial skin with favourable dartos tissue for penile skin coverage. The glans is closed using a stitch-by-stitch method that has not been described previously.

CONCLUSION

This study presents a novel technique for mid-penile hypospadias repair using a preputial skin flap with excellent results in terms of short- and long-term outcomes.

Results of a Two-stage Technique for Treatment of Proximal Hypospadias with Severe Curvature: Creation of a Urethral Plate Using a Vascularized Preputial Island Flap

PURPOSE

To present the results of a two-stage technique used for the treatment of proximal hypospadias with severe curvature.

MATERIALS AND METHODS

The medical records of children with proximal hypospadias and severe curvature were retrospectively analyzed. A 2-stage procedure was performed in 30 children. In the first stage, the release of chordee was performed, and a well-vascularized preputial island flap was created. The vascularized island flap was brought anteriorly and sutured over the ventral surface of the glans and degloved penile shaft. The second stage was performed 6-8 months later. A neourethra was reconstructed by the tubularization of the preputial-urethral plate utilizing the principles of Duplay technique. All surgical procedures were performed between 2005 and 2011.

RESULTS

The mean age of the patients was 4.4 years (1-17 years). The mean duration of urethral catheterization was 6 days after the first stage and 10 days following the second stage. The flaps were viable in all of the children. There was no residual chordee. Following the second stage (n = 30), complications developed in 11 children (36%), namely, a fistula in 7, a pinpoint fistula in 3, and a diverticulum formation in 1. The cosmetic outcome was satisfactory. Uroflowmetry measurements were evaluated, and only one patient had a diverticulum formation at the late follow-up.

CONCLUSION

Vascularized preputial island flap is an alternative to free grafts for the reconstruction of the urethra. The main advantage of this flap technique is the creation of a thick, healthy and well-vascularized urethral plate. The advantages of this technique include better aesthetic appearance, an acceptable complication rate, and a very low rate of diverticula formation.

Complications following Staged Hypospadias Repair Using Transposed Preputial Skin Flaps

PURPOSE

Proximal hypospadias repair using a staged approach is a complex reconstructive operation with the potential for significant complications requiring repeat surgery. We report outcomes of staged hypospadias repair using transposed preputial skin flaps and factors predictive of postoperative complications.

MATERIALS AND METHODS

We retrospectively analyzed patients who underwent staged proximal hypospadias repair using transposed preputial skin flaps between 2002 and 2013. Patient demographics, operative details, complications, reoperations and factors predictive of complications were reviewed.

RESULTS

A total of 56 patients were identified with a mean age of 14.1 months (median 14.3) at first stage. Mean followup was 38.6 months (median 34.1). Complications requiring additional unplanned operation(s) were observed in 38 patients (68%), including fistulas in 32 (57%), diverticula in 8 (14%), meatal stenosis in 5 (9%), urethral stricture in 8 (14%) and glans dehiscence in 3 (5%). In addition, redo first stage repair was performed in 4 patients (7%). Since some patients had more than 1 complication, the total number of complications is greater than the number of patients undergoing a redo operation. On univariate analyses the use of small intestinal submucosa was significantly associated with an increased risk of fistula (91% vs 49%, p = 0.02) and urethral diverticulum (64% vs 24%, p = 0.04). Incision of the tunica albuginea of the corpora was associated with an increased likelihood of fistula (77% vs 44%, p = 0.03). Finally, patients with glans dehiscence were significantly younger at first stage (5.8 vs 14.8 months, p = 0.01).

CONCLUSIONS

The reoperation rate for complications in children undergoing staged hypospadias repair using transposed preputial skin flaps is higher than previously reported.

[Fundamentals and principles of grafts and flaps]

Reconstructive surgery of large urethral stenosis and the management of congenital anomalies such as hypospadias and epispadias require covering large cutaneous and mucosal defects with different techniques. The objective of this work is to define the main differences between tissues to be transferred and to study the principles that must govern the management of the various flaps and grafts used for these techniques. We analyze the anatomical and physiological features that may be key to understand the success and possible failures of these procedures, and we review technical details that must accompany in every case, not only during the operation, but also during the preoperative and postoperative period. We conclude stating that grafts (mainly oral and preputial mucosa) and flaps are increasingly used for the repair of urethral stenosis. Grafts must be prepared adequately in the back table and thinned to the maximum, and also be fixed properly, to guarantee their immobility until neovascularization is assured.

[Pedicled prepuce flap plasty: results in patients with hypospadias or urethral sticture]

BACKGROUND

Operative interventions of the urethra remain challenging procedures. The vascular onlay flap of the inner prepuce is a possible technique for short and long segment urethral defects.

PATIENTS AND METHODS

A total of 195 patients were surgically treated with a vascular prepuce flap between 1994 and 2010 at the Urology Department of Essen Medical University. Patient data were analyzed retrospectively and a questionnaire was sent to all patients.

RESULTS

Of the patients 115 answered the questionnaires and were included in the study. Of these 61 patients were treated in childhood due to hypospadias and 54 patients suffered from acquired urethral stricture. Major complications were postoperative fistulas in 8.2 % and 7.4 % and hematomas in 6.6 % and 11.1 % of cases, respectively. Operative revision had to be performed in 13.1 % and 14.8 % of cases and severe obstructive micturition problems (IPSS score ≥ 20) were observed in only 3.3 % and 11.1% of patients, respectively. Subjective overall satisfaction with the result of the operation was high (67.2 % and 88.9 %, respectively).

CONCLUSION

The vascular prepuce flap is a reliable method for correction of short and long segment urethral defects and is associated with high patient satisfaction.

Feeder layer- and animal product-free culture of neonatal foreskin keratinocytes: improved performance, usability, quality and safety

Since 1987, keratinocytes have been cultured at the Queen Astrid Military Hospital. These keratinocytes have been used routinely as auto and allografts on more than 1,000 patients, primarily to accelerate the healing of burns and chronic wounds. Initially the method of Rheinwald and Green was used to prepare cultured epithelial autografts, starting from skin samples from burn patients and using animal-derived feeder layers and media containing animal-derived products. More recently we systematically optimised our production system to accommodate scientific advances and legal changes. An important step was the removal of the mouse fibroblast feeder layer from the cell culture system. Thereafter we introduced neonatal foreskin keratinocytes (NFK) as source of cultured epithelial allografts, which significantly increased the consistency and the reliability of our cell production. NFK master and working cell banks were established, which were extensively screened and characterised. An ISO 9001 certified Quality Management System (QMS) governs all aspects of testing, validation and traceability. Finally, as far as possible, animal components were systematically removed from the cell culture environment. Today, quality controlled allograft production batches are routine and, due to efficient cryopreservation, stocks are created for off-the-shelf use. These optimisations have significantly increased the performance, usability, quality and safety of our allografts. This paper describes, in detail, our current cryopreserved allograft production process.

[Urethroplasty with pedunculated preputial flap and testicular tunica vaginalis for long anterior urethral stricture: A case report and review of the literature]

OBJECTIVE

To explore the treatment of urethral stricture.

METHODS

We retrospectively studied the clinical data of 1 case of long anterior urethral stricture treated by urethroplasty with pedunculated preputial flap and testicular tunica vaginalis, and summarized the treatment of the disease with review of the relevant literature.

RESULTS

The operation was smooth and successful, and no such complications as fistula and urethral stricture were found during the follow-up.

CONCLUSION

Urethroplasty with pedunculated preputial flap and testicular tunica vaginalis as a substitute is feasible for the treatment of urethral stricture. The key to a successful operation is the proper choice of a urethral substitute.

[Human foreskin acellular matrix graft: a good scaffold for urethral tissue engineering]

OBJECTIVE

To provide evidence of using the human foreskin acellular matrix graft for urethral tissue engineering. METH-ODS: The human foreskin acellular matrix graft was prepared, its safety and biocompatibility as urethral material were determined by histological observation, cytotoxicity test using primary epithelial cells and experiment in vivo.

RESULTS

Intact cells were absent from the foreskin acellular matrix graft. The cytotoxicity test showed that the relative growth rate of the cells was between 75% and 99%, and the cytotoxicity of the foreskin acellular matrix graft was grade 1, consistent with the national standard. With the lengthening of time, the foreskin acellular matrix graft became perfectly compatible with the urothelial cells and the urethral multi-layer structure was restored to normal gradually.

CONCLUSION

The human foreskin acellular matrix graft, with its low antigenicity and good biocompatibility, could be a good scaffold for urethral tissue engineering.

Dorsal inlay graft urethroplasty for primary hypospadiac repair

OBJECTIVE

Tubularized incised plate urethroplasty has become a popular technique for repairing distal and proximal hypospadias in many institutions. Dorsal inlay graft urethroplasty has been used in our institution since 2003 to reduce the risk of meatal stenosis. In the present study, we evaluated the results of the dorsal inlay graft procedure.

METHODS

A total of 28 patients with no deep groove and no severe curvature underwent one-stage urethroplasty using an inner preputial-based dorsal inlay graft. The medical records of all patients were retrospectively reviewed with regard to complication rate and cosmetic appearance.

RESULTS

Mean patient age at surgery was 21 months (range, 14 months to 4.6 years). Preoperatively the urethral meatus was coronal in two cases, distal shaft in 17, proximal shaft in six and penoscrotal in three. Nine patients required testosterone therapy before surgery. Mean operative time was 200 min (range, 154-249 min). Mean length of inlay graft was 20.9 mm (range, 12-30 mm). In all patients, a straight penis was achieved without dorsal plication of the corposa cavernosa, and the neomeatus with a slit-like appearance was positioned at the glans tip. At a mean of 22 months of follow up, a urethrocutaneous fistula developed in only one patient (3.6%), requiring repair surgery 6 months after urethroplasty. No patient had meatal stenosis, neourethral stricture or urethral diverticulum along the inlay graft.

CONCLUSION

Dorsal inlay graft urethroplasty is an effective method for hypospadiac repair and leads to good cosmetic outcome with low risk of complications.

Dorsal on-lay preputial graft urethroplasty for anterior urethra strictures repair

OBJECTIVES

To report the long-term results and evaluate the effectiveness of the dorsal on-lay preputial graft urethroplasty in patients suffering from anterior urethra strictures.

METHODS

A total of 21 male patients, mean age 46.3 years (range 17-67), with anterior urethral strictures, underwent the dorsal on-lay preputial graft urethroplasty during the last 8 years, from October 1997 to September 2005. Strictures were located in bulbar urethra in 16 patients and in penile urethra in the remaining 5. The aetiology the stricture was traumatic injury of the anterior urethra in 12 patients and iatrogenic in 9 patients. A direct vision dorsal urethrotomy and the insertion of an urethral Foley catheter right before the procedure, facilitated the corpus spongiosum dissection and the preparation for urethroplasty. A voiding cystogram was performed on the day of urethral catheter removal to exclude extravasation and estimate the postoperative result.

RESULTS

Mean follow-up time has been 49.9 months (range 6-95) and the outcome was favourable in 15 patients (71.43%). There were 3 recurrences in penile urethra strictures managed conservatively and three in bulbar urethroplasties, treated with internal urethrotomy followed by urethral dilatations.

CONCLUSION

Our results indicate that dorsal on-lay urethroplasty using preputial graft is an easy to learn and perform procedure, and offers the patient durable results with rather minimal complications.

Urethral replacement using epidermal cell-seeded tubular acellular bladder collagen matrix

OBJECTIVES

To investigate the feasibility of replacing urinary epithelium cells with foreskin epidermal cells to reconstruct engineered anterior urethra with an acellular collagen matrix.

MATERIALS AND METHODS

Acellular collagen matrices were generated from allogeneic rabbit bladder submucosa. In nine rabbits, autologous foreskin epidermal cells were isolated, expanded in vitro, and labelled with 5-bromo2'-deoxy-uridine (BrdU) before seeding onto a tubular acellular collagen matrix (1.5x1 cm). In male rabbits, a urethral mucosal defect was created, and urethroplasty performed with a tubular acellular collagen matrix seeded with epidermal cells (nine rabbits) or with a matrix with no cell seeding (nine rabbits; control group). Urethrography was done at 1, 2 and 6 months after grafting. The urethral grafts were harvested and analysed grossly and histologically.

RESULTS

In the control group, gross views and urethrography revealed stricture of repaired defects at the different sample times. In the experimental group, a wide urethral calibre was maintained with no sign of strictures. Histology in the control group showed a single layer of epithelium cells with disorganized muscle fibre bundles in the submucosa layer at 1 month after grafting, and a transitional cell layer surrounded by disorganized muscle fibre bundles at 2 and at 6 months. Grafts seeded with epidermal cells formed a single-layer structure by 1 month, and at 2 and 6 months there were several layers of epidermal cells with abundant vessels in the submucosa. There was an evident margin between graft epidermal cells and host epithelium at 6 months. The implanted cells expressed keratin, shown by staining with anti-pancytokeratins. Immunofluorescence for BrdU confirmed the presence of implanted epidermal cells at 1 month after grafting; there were fewer positive cells at the implantation site at 2 months. At 6 months, there were several layers of epidermal cells with no signs of BrdU staining.

CONCLUSIONS

Urethral reconstruction was better with an acellular collagen matrix seeded with epidermal cells than with the acellular collagen matrix alone. Foreskin epidermal cells seem adequate in replacing urethral epithelium cells for urethral reconstruction.

[Dorsal onlay urethroplasty with foreskin mucosa free graft (Barbagli's technique): preliminary results of our case series]

OBJECTIVES

We evaluate the indication and results in the treatment of complex urethral stenosis by the Barbagli's technique.

METHODS

We retrospectively review 8 patients undergoing dorsal onlay urethroplasty with foreskin mucosa free graft. We analyze their preoperative characteristics. Mean stenosis length was 6.25 cm and the site was bulbar urethra in seven cases and penile in one. Mean preoperative flow was 8.78 ml/sec. We describe the technique and present our results.

RESULTS

There are 87.5% of goods results (cure of the stenosis) with 22 months of mean follow-up. Only one patient required a second operation (end to end anastomosis) with good outcome.

CONCLUSIONS

The dorsal onlay urethroplasty with foreskin mucosa free graft is an effective technique in long and complex urethral stenosis, and we consider it the technique of first choice in view of our results.

[Inner preputial skin grafts combined with preputial island flap for treatment of penile hypospadias]

OBJECTIVE

To investigate new methods of treatment for penile hypospadias. METHODS Urethroplasty was performed for penile hypospadias using inner preputial skin grafts combined with preputial island flap.

RESULTS

A total of 10 patients have received this procedure. After a mean follow up of one year, no fistula or urethral stricture was found. All patients obtained excellent cosmetic results.

CONCLUSIONS

This method allows for adequate correction of severe chordee. It is a useful procedure for selected cases of primary hypospadias with severe incurvation.