Width proportion of the urethral plate to the glans can serve as an appraisal index of the urethral plate in hypospadias repair

Widening of narrow urethral plates with lateral skin in TIP hypospadias repair: single center series

BACKGROUND

To compare the outcomes of hypospadias repair using tubularized incised plate (TIP) urethroplasty and modified TIP with lateral skin to widen the urethral plate (WTIP).

MATERIALS AND METHODS

Data were obtained from pre-pubertal boys who underwent primary hypospadias repair between May 2018 and July 2023. The cases were divided into two groups; one group underwent TIP with urethral plate ≥ 6 mm width and the other group with urethral plate width < 6 mm underwent WTIP. WTIP urethroplasty was performed by widening incisions on the outer margins of the urethral plate to incorporate penile and glandular skin lateral to the urethral plate to facilitate tubularization. Complication rates and urinary functions were compared.

RESULTS

A total of 157 patients were enrolled in this study. Eighty-eight cases with narrow urethral plate were subjected to WTIP urethroplasty, and the rest were subjected to TIP urethroplasty. The preoperative glans width in WTIP group was less than that in TIP group (P < 0.001), and 44.3% had midshaft meatus in WTIP group compared to 17.4% in TIP group (P < 0.001). However, the incidences of postoperative complications (17.6% vs. 21.6%, P = 0.550) were not statistically different between the TIP and WTIP groups. In addition, both groups did not differ significantly in postoperative uroflowmetry assessment.

CONCLUSIONS

The described technique helps to create an adequately caliber aesthetic neomeatus and facilitates tubularization, especially in hypospadias with a narrow urethral plate. Our data suggest that augmentation of a narrow urethral plate with WTIP has a similar surgical outcome to that of the TIP procedure in patients with a wide urethral plate.

Deep learning based automated quantification of urethral plate characteristics using the plate objective scoring tool (POST)

INTRODUCTION

The plate objective scoring tool (POST) was recently introduced as a reproducible and precise approach to quantifying urethral plate (UP) characteristics and guide to selecting particular surgical techniques. However, defining the landmarks mandatory for the POST score from captured images can potentially leads to variability. Although artificial intelligence (AI) is yet to be wholly accepted and explored in hypospadiology, it has certainly brought new possibilities to light.

OBJECTIVES

To explore the capacity of deep learning algorithm to further streamline and optimize UP characteristics appraisal on 2D images using the POST, aiming to increase the objectivity and reproducibility of UP appraisal in hypospadias repair.

METHODS

The five key POST landmarks were marked by specialists in a 691-image dataset of prepubertal boys undergoing primary hypospadias repair. This dataset was then used to develop and validate a deep learning-based landmark detection model. The proposed framework begins with glans localization and detection, where the input image is cropped using the predicted bounding box. Next, a deep convolutional neural network (CNN) architecture is used to predict the coordinates of the five POST landmarks. These predicted landmarks are then used to assess UP characteristics in distal hypospadias.

RESULTS

The proposed model accurately localized the glans area, with a mean average precision (mAP) of 99.5% and an overall sensitivity of 99.1%. A normalized mean error (NME) of 0.07152 was achieved in predicting the coordinates of the landmarks, with a mean squared error (MSE) of 0.001 and a 2.5% failure rate at a threshold of 0.2 NME.

DISCUSSION

Our results support the possibility of further standardizing UP assessment from captured hypospadias images, and the use of machine learning algorithms and image recognition shows that these novel artificial intelligence technologies are useful for scoring hypospadias. External validation can provide valuable information on the generalizability and reliability of deep learning algorithms, which can aid in assessments, decision-making and predictions for surgical outcomes.

CONCLUSIONS

This deep learning application shows robustness and high precision in using POST to appraise UP characteristics. Further assessment using international multi-centre image-based databases is ongoing.

Spongioplasty with Buck's fascia covering dorsal inlay graft urethroplasty for primary hypospadias repair

INTRODUCTION

Neourethral covering is an essential technique for preventing complications such as fistula and glans dehiscence in hypospadias repairs. The spongioplasty has been reported for neourethral coverage about 20 years ago. However, reports of the outcome are limited.

OBJECTIVE

This study aimed to retrospectively evaluate the short-term outcome of spongioplasty with Buck's fascia covering dorsal inlay graft urethroplasty (DIGU).

METHODS

From December 2019 to December 2020, 50 patients with primary hypospadias (median age at surgery, 37 months; range, 10 months-12 years) were treated by a single pediatric urologist. The patients underwent spongioplasty with Buck's fascia covering dorsal inlay graft urethroplasty in single stage. The penile length, glans width, urethral plate width and length, and the location of the meatus of the patients were recorded preoperatively. The patients were followed up,complications noted, and postoperative uroflowmetries at the one-year follow-up time were evaluated.

RESULTS

The average width of glans was 12.92 ± 1.86 mm. A minor penile curvature was observed in all patients (≤30°). The patients were followed up for 12-24 months, and 47 patients (94%) were free from complications. A neourethra formed with a slit-like meatus at the tip of the glans, and the urinary stream was straight. Three patients had coronal fistulae (3/50) and no glans dehiscence, and the mean ± SD Q_max of postoperative uroflowmetry was 8.13 ± 3.8 ml/s.

DISCUSSION

This study estimated the short-term outcome of the DIGU covered using spongioplasty with Buck's fascia as the second layer in patients diagnosed with primary hypospadias with a relatively small glans (average width <14 mm). However, only a few reports emphasize spongioplasty with Buck's fascia as the second layer and the DIGU procedure performed on a relatively small glans. The major limitations of this study were its short follow-up time and the retrospective data collection.

CONCLUSIONS

Dorsal inlay graft urethroplasty combined with spongioplasty with Buck's fascia as coverage is an effective procedure. In our study, this combination had good short-term outcomes for primary hypospadias repair.

Glans Diameter and Meatus Localization Are the Sole Predictors of Primary Distal Hypospadias Surgery Complications: A Multivariate Analysis of Single Surgeon Series

INTRODUCTION

Tubularized incised plate urethroplasty (TIPU) surgery is among the most successful techniques for distal hypospadias. Our objective was the investigation of complication rates and their predictors.

METHODS

Between 2010 and 2021, 150 patients with distal hypospadias were operated on consecutively by a single surgeon using the TIPU technique. The primary outcome was the complication rates including fistula, meatal stenosis, and glans dehiscence. Secondary outcomes were predictor factors of complications.

RESULTS

The average glans diameter was 13.9 ± 0.10 mm and 57.0% of the patients had a glans diameter greater than 14 mm. Single-layer and double-layer urethroplasty were used in 55.3% (n = 83) and 44.7% (n = 67) of patients, respectively. Overall complication rate was 23.3% (n = 35), which included fistula (3.3%, n = 5), glans dehiscence (12.7%, n = 19), and meatal stenosis (8.6%, n = 13). Glandular meatus localization (OR = 58.8, p = 0.001) and smaller glans diameter (OR = 0.39, p = 0.001) were significant predictors in the multivariate analysis of overall complications. For fistula complications, only short operation time (OR = 0.83, p = 0.03) was found as a significant predictor. Glans width (<14 mm) was the only significant predictor of both glans dehiscence (OR = 3.4, p = 0.03) and stenosis (OR = 5.67, p = 0.013) complication.

CONCLUSION

TIPU technique for distal hypospadias has notable success and acceptable complication rates. Dartos augmented single-layer urethral closure seems adequate for complication prevention. Preoperative assessment of the glans width and meatus site is advised to predict complication rates.

Urethral Plate Characteristics in Cases of Non-proximal Hypospadias May Not Be Associated With a Higher Risk of Complications When a Two-Stage Repair Is Applied

PURPOSE

To investigate whether a two-stage repair of distal- and mid-shaft hypospadias (non-proximal hypospadias) could eliminate the risk factors resulting from adverse urethral plate characteristics and eventually reduce complication rates.

METHODS

We retrospectively reviewed all cases of primary surgical repair of non-proximal hypospadias performed in our center between 2009 and 2018. In all cases where adverse urethral plate characteristics were found, such as meatal stenosis, a shallow urethral groove, a thick web of tissue between the native meatus and the urethral groove or in the presence of a very "thin," skin-like distal urethra, a two-stage repair was routinely undertaken. In cases of native meatal stenosis, a meatotomy, and meatoplasty were performed. In cases of a very "thin" distal urethra we incised the skin proximally up to the point of a normal urethral fold and a meatoplasty was performed at that point. Hypospadias repair was then performed in a second operation, 3-6 months following the first procedure. Urethroplasty, both in cases of a single-stage repair and in cases of a two-stage repair, was always performed using the Thiersch-Duplay technique. Patients with a follow-up of less than 12 months were excluded from this study.

RESULTS

Over a period of 10 years, 208 boys underwent primary surgical repair of non-proximal hypospadias. Eighty-nine of the 208 patients (42.8%) underwent single-stage hypospadias repair. Two-stage repair of the hypospadias was required in 119 (57.2%) of the patients. The overall complication rate was 3.4% in the group operated in a single stage and 7.6% in the group that required a two-stage repair (p = 0.09). The most frequent complication reported was urethrocutaneous fistula (p = 0.31), followed by meatal stenosis (p = 0.37), urethral stricture (p = 0.08) and wound dehiscence (p = 0.16). There was no significant difference between the complication rates of the two groups.

CONCLUSION

Patients with distal hypospadias and poor urethral plate characteristics repaired in a two-stage approach have comparable low-complications to those with favorable urethral plate characteristics repaired in a single-stage.

Urethral plate quality assessment and its impact on hypospadias repair outcomes: A systematic review and quality assessment

BACKGROUND

The variability of the urethral plate (UP) characteristics is one of the factors that influence technical choices for hypospadias correction. However, it is difficult to objectively evaluate the UP, leading to controversies in this subject, and vague terms utilized in the literature to describe its characteristics.

OBJECTIVE

We aim to analyze the previously described methods used to characterize and evaluate UP quality, emphasizing the pros and cons of each system, and highlighting its possible influence on different postoperative outcomes.

METHODS

We searched the databases PubMed, Embase, and Cochrane Library CENTRAL from January 1, 2000 to August 20, 2020. The following concepts were searched: urethra reconstruction/urethra replacement/urethroplasty AND hypospadias/hypospadias, AND children AND "plate" with the gray literature search. Subgroup analyses were also carried out. The quality of the involved studies was reviewed operating a modified version of the Newcastle-Ottawa Scale (NOS).

RESULTS

996 citations perceived as relevant to screening were retrieved. Thirteen studies were included comprising a total of 1552 cases. The number of patients in each study varied between 42 and 442, and the average post-surgical follow-up duration ranged between 6 months and twenty-six months. All studies used postoperative urethral stents of variable sizes and types. The impact of UP was most frequently assessed for cases treated with the tubularized incised plate (TIP) repair.

CONCLUSION

The UP quality seems to play a role as an independent factor influencing postoperative outcomes of hypospadias repair. Currently used strategies for the appraisal of UP quality are highly subjective with a low index of generalizability. Various attempts to overcome these limitations exist but none was consistently accepted, leaving a wide space for creative investigation in order to obtain an objective, reproducible, precise, and well-validated tool.

The association between caudal block and urethroplasty complications of distal tubularized incised plate repair: experience from a South China National Children's Medical Center

Background

The effect of caudal block (CB) on the incidence of urethroplasty complications in hypospadias repair remains controversial. The evidence is conflicting, and some confounding bias issues need to be addressed. We sought to study a more homogenous group of distal hypospadias patients undergoing primary tubularized incised plate (TIP) repair by a senior pediatric urology surgeon in the past 2 years to examine the relationship between urethroplasty complications and the use of CB.

Methods

We reviewed our database to identify consecutive patients who had undergone hypospadias repairs by a senior director surgeon at our Center between January 2018 and November 2020. To be eligible to participate in the study, patients had to meet the following inclusion criteria: (I) have distal hypospadias; (II) have undergone a primary TIP repair; and (III) have attended follow-up appointments for a minimum period of 6 months. The primary outcome was the development of urethroplasty complications during the follow-up period. The principal variable of interest was whether or not CB was used perioperatively. The patients were categorized into a CB group (general anesthesia combined with CB) or a control group (general anesthesia only). Other potential risk factors were analyzed, including patient age at operation, patient weight, glans width, and the length of the urethral plate defect.

Results

Thirty (12.2%) of the distal patients developed postoperative surgical complications. The postoperative surgical complication rates were similar between the different anesthesia groups. Weight, the length of the urethral plate length, and glans width did not contribute to the risk. Age was the only independent risk factor for postoperative surgical complications, and the complication rates increased in older patients.

Conclusions

Our data from consecutive TIP repairs in distal hypospadias patients indicated no association between the use of CB anesthesia and the postoperative urethroplasty complication rate. Patients who were older in age when they underwent surgery had a higher risk of complications.

Repair of distal hypospadias by construction of neourethra from augmented urethral plate with two lateral strips of glans skin and coverage with dartos flap followed by skin closure with preputial flap: single center series

Introduction

Hypospadias is one of the most common anomalies in boys. Many surgical techniques for reconstruction of distal hypospadias have been described, each method having a different success rate. Our objective in this study is the assessment of the surgical technique for repair of distal hypospadias by construction of a neourethra from the augmented urethral plate with two lateral strips of glanular skin, coverage with a dartos flap, and followed by skin closure with preputial skin flap.

Material and methods

From March 2016 to November 2018, repair of distal hypospadias was performed in 56 children with a mean age of 3.2 years (range 2 to 8 years old). Minimum follow-up was 12 months, maximum up to 24 months. Success was defined by cosmetic appearance of the penis, parent perception of penile appearance, and urinary function. Uroflowmetry was done in 22 children at the 12 months follow-up. Parents evaluation of procedure was done by questionnaire using the pediatric penile perception score (PPPS).

Results

The results were successful with straight penile shaft, conical glans, slit-like meatus located at the tip of the glans, with no rotation, and normal micturition. Five children had urethrocutaneous fistula (8.9%) that were treated with simple closure. Parents reported 'very satisfactory' (98.2%) and 'satisfactory' (1.8%).

Conclusions

The described technique of repair of distal hypospadias in children with different variants of urethral plate width and glans size showed good results, both operator's and parent's perception of the results being very satisfactory. This technique is categorised stage 2a in the IDEAL (Idea, Development, Evaluation, Assessment, and Long-term study) staging system for surgical innovations.

Identification of risk factors associated with numerous reoperations following primary hypospadias repair

INTRODUCTION

Complications remain the top evaluation priority subsequent to hypospadias repair. Complications vary in further management, and usually require one or more reoperations. Patients and/or their parents concern not only with the success rate of reoperation, but also with the risk of numerous reoperations.

OBJECTIVE

To identify the risk factors associated with numerous reoperations following primary hypospadias repair.

STUDY DESIGN

Data were collected retrospectively from patients who underwent reoperations for complications following primary hypospadias repair at a single institution from August 2008 to October 2017.

RESULTS

A total of 507 patients required reoperations following 2754 primary hypospadias repairs. Eventually, 486 patients were eligibly included with a median age of 2.2 years. The median follow-up period was 6.5 years. Preserved urethral plate urethroplasty for primary repair (including Snodgrass, Onlay and Mathieu techniques) was performed in 307 (63.2%) patients, Duckett technique was performed in 121 (24.9%) patients, and staged urethroplasty (including staged Duckett, Byars and Bracka techniques) was performed in 58 (11.9%) patients. The complications included 302 fistulas, 108 dehiscence, 50 urethral strictures, 18 meatal stenosis, 38 diverticula, 24 mild recurrent ventral curvature and 23 severe recurrent ventral curvature. A total of 363 (74.7%) patients needed 1 reoperation, 87 (17.9%) needed 2 reoperations, 19 (3.9%) needed 3 reoperations, and 17 (3.5%) needed >3 reoperations. Ordinal logistic regression demonstrated that severe recurrent ventral curvature, urethral stricture, dehiscence and primary staged hypospadias repair increased the risk of numerous reoperations, with odds ratios of 75.991-fold, 36.967-fold, 11.765-fold and 3.074-fold, respectively. In contrast, diverticulum decreased the risk, with an odds ratio of 0.443-fold.

DISCUSSION

Our data demonstrated significant heterogeneity in the risk of numerous reoperations for each complication. Severe recurrent ventral curvature conferred the highest risk of numerous reoperations, followed by urethral stricture, dehiscence. In additional, our data showed an increased risk of numerous reoperations following primary staged repairs. Identification the risk factors confers advantages in the assessment of postoperative outcomes and anticipation of future reoperations.

CONCLUSION

Severe recurrent ventral curvature, urethral stricture, dehiscence and primary staged hypospadias repair were associated with numerous reoperations following primary hypospadias repair.

Urethral plate in tubularized incised plate urethroplasty: how wide is enough?

Background

Previous reports found that a preincision urethral plate (UP) width <8 mm increased the occurrence of urethroplasty complications (UCs) in tubularized incised plate (TIP) hypospadias repair. However, is the classification of the UP width based on an 8 mm cut-off value to predict the outcome of TIP urethroplasty objective enough or universally applicable? The purpose of our study was to assess the effect of the UP width on the outcomes of TIP hypospadias repair in the Eastern population we served.

Methods

We retrospectively reviewed the records of patients who underwent TIP hypospadias repair by the same surgeon between August 2013 and December 2019 in our hospital. Data were collected, including demographics, intrinsic parameters of the penis, surgical parameters and subsequent surgical outcomes. The data were analyzed and the cut-off value of the UP width was calculated using a receiving-operator curve.

Results

Primary TIP urethroplasty was carried out in 116 patients with a mean age of 35.89±29.40 months. The meatal location was distal in 49 patients, midshaft in 56 patients and proximal in 11 patients. The mean glans width was 12.28±1.36 mm, the mean UP width was 5.74±1.37 mm, the mean neourethral length was 1.96±1.32 cm, and the mean operation duration was 87.52±11.47 min. During a median follow-up of 42 (range: 6 to 80) months, UCs developed in 12 patients, and the UP width was significantly related to the occurrence of UCs (P=0.014). According to the 6 mm cut-off value of the UP width by the receiver operating characteristic curve, patients were divided into two groups. Group A (UP width ≥6 mm) included 69 patients, and Group B (UP width <6 mm), 47 patients. UCs occurred in 3 patients in Group A vs. 9 patients in Group B, P=0.010.

Conclusions

UP width is a potential risk factor for UCs after TIP hypospadias repair. Using this technique with an UP width ≥6 mm is sufficient to result in a good outcome of hypospadias repair.

Plate Objective Scoring Tool (POST); An objective methodology for the assessment of urethral plate in distal hypospadias

BACKGROUND

Estimation of the quality of the urethral plate (UP) seems to be important when assessing postoperative outcomes of hypospadias repair, but its evaluation remains subjective. We developed an objective model aiming to standardize this assessment, proposing a methodology that could be adopted in future studies designed to evaluate outcomes in the treatment of hypospadias.

OBJECTIVES

To evaluate the inter and intra observer reliability of a method to assess the quality of the urethral plate (UP) in hypospadias (POST - Plate Objective Scoring Tool) based on elements of glans characteristics. The reliability of such scoring methodology was compared to an analog accepted tool: the Glans-Urethral Meatus-Shaft (GMS) score. A secondary goal was to compare some characteristics of the UP in GMS score to POST values; aiming to find the threshold between favorable and unfavorable plates.

METHODS

Data were prospectively obtained from prepubertal boys who underwent primary hypospadias repair between January 2018 and November 2019. Intrinsic elements of the glanular UP (A: distal midline mucocutaneous junction; B: Glanular knob where the mucosal edges of the UP's edge change direction; C: Glanular/coronal junction) were marked and the AB/BC ratio calculated. The "G" and "M" components of the GMS score were measured electronically three times by four different reviewers with variable pediatric urology experience and blinded to each other values. Favorable UP, according to the GMS score was compared to measurements obtained by POST (AB/BC ratio).

RESULTS

84 subjects were enrolled. The POST score had an excellent inter-observer agreement for the evaluation of the UP in distal hypospadias (Kappa = 0.832) while the "G" parameter of the GMS correlated poorly among the observers. The Inter-Class Correlation (ICC) analysis to examine the intra-rater agreement value was 0.914 (95% CI 0.87, 0.95.). AB/BC ratio values ranged from 0.6 to 1.6, with a mean of 1.12. The POST cut-off value for "favorable" UP was 1.2 (AUC = 0.62) 95% CI (0.52-0.84) (sensitivity 80% and specificity 60%).

CONCLUSIONS

The POST score has higher inter-observer reliability and functions favorably when compared to the GMS. In addition, it demonstrated a high intra-observer reliability among observers of variable experience. Our findings suggest that the POST score adds to evaluation of the UP and could be incorporated as an additional criterion to assess outcomes in distal hypospadias repairs.