"Fossa navicularis" and "septum glandis": A "flow-control chamber" for the male urethra?

The Glanular-Frenular Collar (GFC) technique: Dual approach to hypospadias reconstruction

INTRODUCTION

The Glanular-Frenular Collar (GFC) technique has evolved since it was first described in 2017. The technique involves reconstruction of the septum glandis, which has been overlooked in the history of hypospadias, and formation of the frenulum, creating the ventral wall of the glanular urethra without dissecting the glans, leaving room for the formation of the navicular fossa.

MATERIAL AND METHODS

We present a case of distal hypospadias corrected with the GFC technique and demonstrate the important steps of the surgical technique.

RESULTS

The aesthetic result corresponded to the normal anatomy of the glans and frenular triangle, and the functional result showed a free and wavy shape of urine that resembled the normal flow from the urethra.

DISCUSSION

In the normal anatomy of the penis, the wings of the glans are separated ventrally by the septum glandis and the frenulum. The navicular-shaped glanular urethra and its vertical, elliptical opening are covered by the fibroelastic septum glandis, unlike the penile urethra, which is surrounded by the corpus spongiosum.

CONCLUSION

Reconstruction of hypospadias should include the formation of a septum glandis, frenulum, and navicular fossa. The GFC technique demonstrates the importance of a dual surgical approach for glanular and penile urethra reconstruction.

Endocrine outcome and seminal parameters in young adult men born with hypospadias: A cross-sectional cohort study

BACKGROUND

Hypospadias affects around 1/200 newborn males. Intrauterine testicular dysfunction may underlie a subset of cases. The long-term endocrine and reproductive outcomes in these men remain largely unknown.

METHODS

Cross-sectional study in Ghent and Vienna University Hospitals to assess the endocrine and seminal parameters of young adult men (16-21 years) born with non-syndromic hypospadias (NSH) (n = 193) compared to healthy typical males (n = 50). Assessments included physical exam, semen analysis, hormone assays and exome-based gene panel analysis (474 genes).

FINDINGS

All participants had experienced a spontaneous puberty, in spite of higher LH and INSL3 levels than typical males. Oligo- or azoospermia was observed in 32/172 (18·6%; 99%-CI: 12·2-27·4%) of NSH men; but in 5/16 (31·3%; 99%-CI: 11·1;62·4%) of complex NSH men and in 13/22 (59·1%; 99%-CI: 33·2-80·7%) of those born small for gestational age (SGA). No (likely) pathogenic coding variants were found in the investigated genes. Suboptimal statural growth affected 8/23 (34·8%; 99%-CI: 15·4-61·0%) of men born SGA with NSH.

INTERPRETATION

Spermatogenesis is significantly compromised in NSH men, especially in those born SGA or those with complex NSH. Long-term andrological follow-up is recommended, including end-pubertal semen analysis. No clear monogenic causes could be demonstrated in our cohort even in proximal or complex NSH. Being born SGA with NSH is frequently associated with poor catch-up growth, requiring growth hormone therapy in some.

FUNDING

Research grants from the European Society of Paediatric Endocrinology, the Belgian Society of Pediatrics, the Belgian Society of Pediatric Endocrinology and Diabetology and the Research Foundation Flanders (FWO).

Nomogram of paediatric male urethral size: A systematic review

INTRODUCTION

Knowledge of the normal size of the urethral meatus in boys is important for safely performing urethral catheterization and fundamental to the diagnosis and treatment of paediatric urological conditions. However, clinicians often rely subjectively on previous experience and clinical judgement, rather than a robust evidence-base. A systematic review of the literature was undertaken to define the calibre of the male urethral meatus in paediatric age-groups.

METHODS

The MEDLINE and EMBASE databases were systematically searched from inception to December 2020 for studies measuring meatal calibre in boys up to 16 years of age. Google Scholar searches along with forward and backward citation tracking identified additional studies. Studies of subjects >16 years, females, or patients with urethral diseases were excluded.

RESULTS

Nine articles (2084 paediatric subjects) were included in the final review. Mean meatal calibre increases non-linearly with age, with accelerated growth occurring during infancy (mini-puberty) and adolescence (puberty). Meatal calibre can be approximately grouped by age as follows: neonate (6-10Fr); infant (10-12Fr); child (12-14Fr); and adolescent (14-18Fr). There is substantial individual variability for same-aged children. Meatal calibre has been independently related to height, weight, and penile size, but the effects of ethnicity and circumcision remain unclear.

CONCLUSIONS

The evidence-base for this fundamental aspect of paediatric urology includes only a few low-quality studies and is largely derived from one early study of circumcised American boys. Further studies are warranted to establish normative urethral size values based on rigorous, contemporary data with known dependent variables also included.

Establishment of mouse line showing inducible priapism-like phenotypes

Purpose

Penile research is expected to reveal new targets for treatment and prevention of the complex mechanisms of its disorder including erectile dysfunction (ED). Thus, analyses of the molecular processes of penile ED and continuous erection as priapism are essential issues of reproductive medicine.

Methods

By performing mouse N‐ethyl‐N‐nitrosourea mutagenesis and exome sequencing, we established a novel mouse line displaying protruded genitalia phenotype (PGP; priapism‐like phenotype) and identified a novel Pitpna gene mutation for PGP. Extensive histological analyses on the Pitpna mutant and intracavernous pressure measurement (ICP) and liquid chromatography–electrospray ionization tandem mass spectrometry (LC–ESI/MS)/MS analyses were performed.

Results

We evaluated the role of phospholipids during erection for the first time and showed the mutants of inducible phenotypes of priapism. Moreover, quantitative analysis using LC–ESI/MS/MS revealed that the level of phosphatidylinositol (PI) was significantly lower in the mutant penile samples. These results imply that PI may contribute to penile erection by PITPα.

Conclusions

Our findings suggest that the current mutant is a mouse model for priapism and abnormalities in PI signaling pathways through PITPα may lead to priapism providing an attractive novel therapeutic target in its treatment.

A closer look at iatrogenic hypospadias

Almost all surgical repair techniques for hypospadias include dissection of the glans penis, and covering the neo-urethra with the glans tissue circumferentially. Surprisingly, the presence of the "septum glandis" in the ventral midline has been overlooked for decades. A careful examination of six patients with iatrogenic hypospadias (IH) revealed direct indications of the septum glandis. All patients were treated with long-term urethral catheterisation in the paediatric intensive care unit due to neurologic and/or metabolic diseases. The glans was disrupted in all patients due to ventral midline compression of the urethral catheter, which resulted in a tear in the septum glandis. A remnant of the septum glandis was clearly observed in patients with an incomplete tear. Further injuries caused tear in the frenulum and corpus spongiosum, exposed the glanular urethra and made its vertical elliptical shape, the "fossa navicularis", visible. Intact contours of the separated glans wings were observed in all patients. The glans wings merge ventrally in the midline, but are separated by a fine connective tissue (septum glandis) in conjunction with the frenulum, which is involved in the formation of the ventral wall of the glanular urethra. IH provides further insight into the structural anatomy of the normal human glans and glanular urethra.