An objective hypospadias classification system

Hypospadias-associated penile curvature assessment and management: A global survey of current practice

INTRODUCTION

Our goal was to assess how surgical management of hypospadias-associated penile curvature (HAPC) varies across continents, focusing on factors that influence assessment and decision-making.

METHODS

Members of the European Society of Pediatric Urology (ESPU), Society of Pediatric Urology (SPU), and Hypospadias International Society (HIS) participated in an anonymous, 34-question online survey addressing pre-, intra-, and postoperative elements of HAPC evaluation and management. A selection of intraoperative photos were included in the survey to investigate the prevailing surgical approaches and identify management patterns.

RESULTS

Out of the 267 participants, 38.4% of them are located in Europe. Visual estimation was the predominant approach for evaluating HAPC, although being regarded as the least dependable compared to other techniques. Surgeons who performed more than 40 cases per year were more inclined to use goniometers and had varying degrees of HAPC that were considered acceptable without requiring any correction (P < .001). Out of 58% of respondents, a significant number reported regular utilization of artificial erection tests for all categories of hypospadias. Surgeons with fewer than 10 years of expertise commonly utilized erection test as part of their regular practice. A tourniquet was employed to maintain sufficient intra-corporeal pressure, by134 (50%). 116 participants (43%) inject Saline through the corpora cavernosa through the glans, while 150 (56%) administer saline from the lateral aspect. Moreover, the decision-making process differed based on the intraoperative picture scenarios of mild to moderate penile curvature during erection testing. Contrary to temperatures ranging from 25o to 35o, decision-making in cases with less severe degrees of HAPC was uncomplicated.

CONCLUSION

This survey reveals a wide range of surgical practice patterns in the assessment and management of HAPC. To our knowledge, this global survey of HAPC practice is the largest to date and could aid in developing new guidelines in pediatric urology. These findings may also provide a foundation for future prospective multinational studies.

Plate Objective Scoring Tool (POST) in distal hypospadias: Correlation with post-repair complications

OBJECTIVES

The Plate Objective Scoring Tool (POST) accurately reflects configuration of the urethral plate in distal hypospadias. Here we assessed whether POST score also correlates with patient risk of complications after surgical repair.

METHODS

Data were obtained prospectively from pre-pubertal boys who underwent primary hypospadias repair between January 2020 and February 2023. Both POST and Glans-Urethral Meatus-Shaft (GMS) scores were determined in triplicate by three independent reviewers before evaluating correlation with complications after surgery.

RESULTS

POST ratios were strongly correlated with incidence of post-repair complications in n = 121 patients. Mean POST score was 1.10 (range 0.5-1.62) and average GMS value was 5.29 ± 1.36 (median G = 2, M = 2, S = 1). Bivariate correlation analysis indicated that POST score can accurately predict risk of complications after surgery (Pearson correlation coefficient r = 0.821 [0.724-0.918], 95 % CI). A POST threshold of 1.2 provided the highest specificity for risk of post-operative complications, which occurred in 4.4 % of patients with POST score ≥1.2 (2/45 cases), compared with 25 % among patients with POST score <1.2 (19/76 cases).

CONCLUSIONS

This study confirms that POST index can be used as a surrogate marker of urethral plate quality and accurately predicts the outcome of distal hypospadias repair. Objective scoring of POST revealed that low ratios were significantly associated with high risk of postoperative complications. In future, this approach could be used to stratify patients and better identify cases that require close follow-up care.

Objective documentation of hypospadias anatomy with three-dimensional scanning

INTRODUCTION

The absence of a standardized classification of hypospadias hinders understanding of the anatomic differences among patients and the evaluation of outcomes following surgical repair. In working towards a standardized, objective method of recording patients' hypospadias anatomy, we describe our initial experience using a non-invasive three-dimensional scanner.

MATERIAL AND METHODS

An Artec3D Space Spider scanner was used to obtain 3D scans in 29 patients undergoing hypospadias repair. Measurements of the urethral plate width, urethral plate length, glans width, penile shaft length, and penile shaft width were made by 2 pediatric urology attendings and 1 pediatric urology fellow. Measurements were compared and inter-rater reliability was calculated.

RESULTS

A total of 435 measurements were made on 29 successfully generated 3D scans, ranging from distal to proximal hypospadias. The inter-rater reliability of measurements from the generated 3D models shown good inter-rater reliability of urethral plate width (ICC0.87 [95%CI:0.76,0.93]), penile shaft length (ICC0.87 [95%CI:0.70,0.94]) and glans width (ICC0.83 [95%CI:0.68,0.92]), excellent inter-rater reliability of urethral plate length (ICC0.96) and moderate inter-rater reliability of penile shaft width (ICC0.69 [95%CI:0.44,0.84]).

DISCUSSION

There was a high degree of reliability of measurements made across multiple users. Calculation of the ratio of the urethral plate length/total penile shaft length objectively defined the initial position of the urethral meatus. When compared to the 3-dimensional volume of the glans, a more proximally positioned urethral meatus was associated with a lower glans volume.

CONCLUSION

3D scanning offers a rapid, reproducible, and non-invasive method of documenting hypospadias anatomy. The ability to evaluate three dimensional features (i.e. glans volume) offers an exciting opportunities for robust investigation of hypospadias outcomes and further understanding of the relationship between a patient's genotype and phenotype.

A mobile application for postoperative education of caregivers of children with congenital hypospadias: Requirement analysis

Background and Aims

Hypospadias, a congenital anomaly, can have long-term effects on sexual, urinary, and reproductive functions, making proper postoperative care essential for desirable outcomes, which could be facilitated through a mobile application for diseases with long-term complications. The aim of this study was to investigate the data and functional requirements or minimum data set of a postoperative education mobile application for caregivers of children with hypospadias.

Methods

A literature review of papers published until April 2023 using Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement was conducted to determine the data and functional requirements of a mobile application that provides postoperative education to caregivers of children with congenital hypospadias. Based on the results, a questionnaire was prepared, and its content validity and reliability were evaluated by CVI and CVR. Additionally, data was examined by 30 residents, specialists, and subspecialists in pediatric surgery using the Delphi approach.

Results

The study identified 28 data elements in three main categories: demographic data, clinical data, and application function. Functional requirements of the mobile application were suggested for use in designing the application. Also, the most critical data elements included the definition of disease, the importance of treatment, surgical preparation, bandage, hygiene, symptoms and infection, bleeding, and emergency condition.

Conclusion

The study will pave the way for developing postoperative educational applications for caregivers of children with congenital hypospadias. M-Health app developers and clinician specialists can utilize these findings to design practical applications that assist caregivers in managing the care of hypospadias patients.

Urologist validation of an artificial intelligence-based tool for automated estimation of penile curvature

INTRODUCTION

Severity of penile curvature (PC) is commonly used to select the optimal surgical intervention for hypospadias, either alone or in conjunction with other phenotypic characteristics. Despite this, current literature on the accuracy and precision of different PC measurement techniques in hypospadias patients remains limited.

PURPOSE

Assess the feasibility and validity of an artificial intelligence (AI)-based model for automatic measurement of PC.

MATERIAL AND METHODS

Seven 3D-printed penile models with variable degrees of ventral PC were used to evaluate and compare interobserver agreement in estimation of penile curvatures using various measurement techniques (including visual inspection, goniometer, manual estimation via a mobile application, and an AI-based angle estimation app. In addition, each participant was required to complete a questionnaire about their background and experience.

RESULTS

Thirty-five clinical practitioners participated in the study, including pediatric urologists, pediatric surgeons, and urologists. For each PC assessment method, time required, mean absolute error (MAE), and inter-rater agreement were assessed. For goniometer-based measurement, the lowest MAE achieved was derived from a model featuring 86° PC. When using either UVI (unaid visual inspection), mobile apps, or AI-based measurement, MAE was lowest when assessing a model with 88° PC, indicating that high-grade cases can be quantified more reliably. Indeed, MAE was highest when PC angle ranged between 40° and 58° for all the investigated measurement tools. In fact, among these methodologies, AI-based assessment achieved the lowest MAE and highest level of inter-class correlation, with an average measurement time of only 22 s.

CONCLUSION

AI-based PC measurement models are more practical and consistent than the alternative curvature assessment tools already available. The AI method described in this study could help surgeons and hypospadiology researchers to measure PC more accurately.

Outcome analysis of staged preputial graft technique for primary proximal hypospadias with and without post-operative vacuum physiotherapy

PURPOSE

Management of proximal hypospadias remains challenging. We assessed the results of staged preputial graft repairs (SPG) for proximal hypospadias and hypothesize that post-operative vacuum physiotherapy (VP) improves graft suppleness and overall outcomes.

MATERIALS AND METHODS

Retrospective analysis of n = 71 patients with proximal hypospadias and severe ventral penile curvature (PC) of ≥50° after degloving. PC was corrected using ventral transverse incisions of the tunica albuginea (VTITA) without applying a tourniquet, taking care to avoid injuring the underlying erectile tissue. The ventral raw area at the penile shaft, including VTITA, were covered with either divided and partially mobilized urethral plate, or with the inner preputial graft itself. During the second stage, a tunica vaginalis flap was often used to cover the tubularized neourethra. Outcomes and post-op complications were assessed after each stage, comparing patients who received vacuum physiotherapy (VP+, n = 49) with those who did not (VP-, n = 22).

RESULTS

Mean PC was 66°, average follow-up duration was 13.01 months, and overall complication rate was 22.5%. Only 6 of 49 VP + patients experienced complications (12.24%; 4 fistulas; 2 urethral strictures) and no recurrence of PC after second stage was observed in this group. VP- patients displayed a significantly higher rate of complications, with 10 of 22 cases (45.45%) exhibiting fistula development (n = 5) and glans dehiscence (n = 5). Recurrence of mild PC after first-stage repair was comparable between patient groups (12% VP+, 18% VP-) and easily corrected by simple graft tubularization or dorsal plication during second-stage repair.

CONCLUSIONS

Staged repair using VTITA is effective for correcting proximal hypospadias with severe chordee. VP appears to promote and expedite graft suppleness and significantly improves patient outcomes.

Neural network non-linear modeling to predict hypospadias genotype-phenotype correlation

INTRODUCTION

Hypospadias is an abnormal development of the urethral, ventral skin and corporeal bodies. Urethral meatus and ventral curvature have been historically the landmarks to define clinical severity. Genotyping has never been explored as a clinical predictor. Available reports have demonstrated a correlation between genetic mutations and syndromic hypospadias with poor surgical outcomes. We hypothesize that inclusion of genotyping can serve at classifying all types of hypospadias. We present the use of neural network algorithm to evaluate phenotype/genotype correlations and propose its potential clinical applicability.

METHODS

A systematic review was performed from January 1974 to June 2022. Literature was retrieved from Medline, Embase, Web of Science and Google Scholar. Included manuscripts were those that had an explicit anatomical description of hypospadias phenotype (urethral meatus location following an anatomical description) and a defined genotype (genetic mutation) description. Cases with more than one variant/mutation were excluded. A comprehensive phenotype-genotype statistical analysis using neural network non-linear data modeling SPSS™ was performed.

RESULTS

Genotype-Phenotype analysis was performed on 1731 subjects. Of those, 959 (55%) were distal and 772 (45%) proximal. 49 genes with mutations were identified. Neural network clustering predicted better for coronal (90%) and glanular (80%), and lowest for midshaft (22%) and perineal (45%). Using genes as predictor factor only, the model was able to highly and more accurately predict the phenotype for coronal and glanular hypospadias. The following genotypes showed association to a specific phenotype: AR gene n.2058G > A for glanular (p<0.0001), n.480C  >  T for coronal (p = 0.034), R840C for perineal (p = 0.002), MAMLD1 gene c.2960C > T for coronal (p< 0.0001), p. G289S for glanular (p<0.0001), gene SRD5A2 607G > A for scrotal (p<0.0001), c16C > T for penoscrotal (p<0.0001), c59 T  >  c for perineal (p = 0.042), V89L for midshaft and scrotal (p<0.0001, p = 0.041; respectively).

DISCUSSION

Hypospadias phenotype has always been described from a purely anatomical perspective. Our results demonstrate that current phenotyping has poor correlation to the genotype. Higher genotype/phenotype correlation for distal hypospadias proves the clinical applicability of genotyping these cases. The concept and classification of differences in sexual development needs to be reconsidered given high positive yield reported for distal hypospadias. Given the better predictive value of genotyping in correlation to the phenotype, future efforts should be directed towards using the genotype.

CONCLUSION

Hypospadias has poor phenotype/genotype correlation. Sequencing all hypospadias phenotypes may add clinical value if used in association to other predictive variables. Neural network analysis may have the ability to combine all these variables for clinical prediction.

Automated measurement of penile curvature using deep learning-based novel quantification method

Objective

Develop a reliable, automated deep learning-based method for accurate measurement of penile curvature (PC) using 2-dimensional images.

Materials and methods

A set of nine 3D-printed models was used to generate a batch of 913 images of penile curvature (PC) with varying configurations (curvature range 18° to 86°). The penile region was initially localized and cropped using a YOLOv5 model, after which the shaft area was extracted using a UNet-based segmentation model. The penile shaft was then divided into three distinct predefined regions: the distal zone, curvature zone, and proximal zone. To measure PC, we identified four distinct locations on the shaft that reflected the mid-axes of proximal and distal segments, then trained an HRNet model to predict these landmarks and calculate curvature angle in both the 3D-printed models and masked segmented images derived from these. Finally, the optimized HRNet model was applied to quantify PC in medical images of real human patients and the accuracy of this novel method was determined.

Results

We obtained a mean absolute error (MAE) of angle measurement <5° for both penile model images and their derivative masks. For real patient images, AI prediction varied between 1.7° (for cases of ∼30° PC) and approximately 6° (for cases of 70° PC) compared with assessment by a clinical expert.

Discussion

This study demonstrates a novel approach to the automated, accurate measurement of PC that could significantly improve patient assessment by surgeons and hypospadiology researchers. This method may overcome current limitations encountered when applying conventional methods of measuring arc-type PC.

Ultrasonographic Evaluation of the Hypospadiac Penis in Children

INTRODUCTION

Identifying key anatomical features of the hypospadiac penis is crucial to better understanding this pathology and guiding surgical reconstruction plans, thereby achieving superior functional and cosmetic outcomes.

OBJECTIVE

To Assess the feasibility and precision of penile ultrasonography (PUG) in determining key structural features for hypospadias cases (including distal extent of the spongiosal component of the urethral plate, to elucidate the healing process following tubularised incised-plate urethroplasty).

PATIENTS AND METHODS

Twenty-five children with hypospadias were assessed using PUG prior to surgical repair and then again under general anesthesia. Preoperative images were acquired using ultrasonography in sagittal and transverse planes, then later compared with anatomical findings obtained during surgical repair of urethral hypoplasia.

RESULTS

Median patient age was 1.2 years (range 0.5-12) and hypospadias types included coronal 17/25 (68%), mid-penile 5/25 (20%), and proximal penile 3/25 (12%). Distinct layers of the corpus spongiosa and mucosal layer, Buck fascia, tunica albuginea, glans, corpora cavernosa, and penile skin were delineated so that their spatial inter-relationship could be assessed. Distal extent of the spongiosal component of the urethral plate was determined by the mid-glans B-B line. The extent of urethral hypoplasia identified by PUG was relatively similar to measurements obtained intraoperatively.

CONCLUSION

PUG is a feasible and accurate approach to evaluating penile configuration in children with hypospadias. Distal extent of the spongiosal component of the urethral plate was accurately determined, hence PUG could potentially be used to improve surgical planning and appraisal of current repair procedures.