Hypospadias Centre, Department of Pediatric Surgery, Emma and Sana Klinikum Offenbach Hospitals, Max-Planck Str.2, Germany.
Institute for Pathology, University Medical Center Goettingen, Germany.
J Pediatr Urol. 2022 Jun;18(3):364.e1-364.e9. doi: 10.1016/j.jpurol.2022.02.006. Epub 2022 Feb 16.
To examine the urethral plate and the underlying tissues in children with proximal hypospadias associated with severe chordee.
The urethral plate and the underlying tissue specimens were excised to correct severe chordee in 17 children with proximal and perineal hypospadias with severe chordee. The median age was 20 months (range 8-36). Sections samples were marked and examined from proximal to distal. Specimens were examined histologically using hematoxylin-eosin (H/E) and Elastic van Gieson (EvG) stain. Histochemical examination was also performed using smooth muscle actin (SMA) and factor 8 antibodies. For control, samples from four patients with hypoplastic urethra proximal to the meatus including the hypoplastic segments until the normal urethra were taken. In addition, the urethra of an adult patient with penile tumor was used as control.
The average size of the 17 tissue samples was 0.5 cm × 0.5 cm x 0.3 cm in depth. There was a common pattern that was seen in all the 17 specimens with a variable degree of expression. H/E staining showed that the epithelial lining changed from pseudostratified epithelium at the proximal intact urethra to non-keratinized stratified squamous epithelium at the urethral meatus to keratinized stratified squamous epithelium distally at the urethral plate level. EvG staining showed overall very few elastic fibres that increased slightly in the distal urethral plate. SMA staining showed a circular pattern of smooth muscle cells in the proximal intact urethra that changed to a U-shaped pattern at the level of the meatus, to a triangle shaped pattern just distal to the meatus. The distal urethral plate showed an irregular, disorganized rather flat pattern of the smooth muscles. Factor 8 antibodies staining the blood spaces revealed dysplastic unorganized large blood sinusoids underneath the urethral plate that were different from normal capillaries surrounding the proximal urethra.
The urethral plate and the underlying tissues in patients with severe chordee have different structure from normal urethra as compared to available literature and the adult control patient. The lack of elastic fibres may help to explain the rigidity of the ventral penis causing chordee. The disorganized irregular distribution of the smooth muscle fibres is suggestive of the hypoplastic corpus spongiosum. The abnormal large blood sinusoids may explain the poor healing quality of the ventral penis in patients with perineal and proximal patients associated with severe chordee. This may explain persistent/recurrent chordee observed later in those patients with severe chordee when dorsal plication is used. The study also supports the recent trend of 2 stage procedure as a plan of management for patients with proximal and perineal hypospadias with severe chordee and excision of all the dysplastic tissues during the first operation.
研究近端型伴严重下弯的尿道下裂患儿的尿道板及其下组织。
17 例近端型及会阴型伴严重下弯的尿道下裂患儿行严重下弯矫正术时，切除尿道板及下组织。中位年龄 20 个月（范围 8-36 个月）。标本从近端至远端标记并进行组织学检查。采用苏木精-伊红（H/E）和弹性 Van Gieson（EvG）染色进行组织化学检查。还使用平滑肌肌动蛋白（SMA）和因子 8 抗体进行组织化学检查。作为对照，取自 4 例近端尿道狭窄患者（包括狭窄段至正常尿道），同时取自 1 例阴茎肿瘤成年患者的尿道作为对照。
17 例组织标本的平均大小为 0.5cm×0.5cm×0.3cm。所有 17 例标本均存在一种共同模式，且具有不同程度的表达。H/E 染色显示，上皮衬里从近端完整尿道的假复层上皮变为尿道口的非角化复层鳞状上皮，再变为尿道板水平的远端角化复层鳞状上皮。EvG 染色显示，整体弹性纤维非常少，远端尿道板处略有增加。SMA 染色显示，近端完整尿道的平滑肌呈圆形，在尿道口水平变为 U 形，在尿道口稍远端变为三角形。远端尿道板显示平滑肌呈不规则、无组织的扁平状。因子 8 抗体染色的血管腔显示，尿道板下有不同的、无组织的大血窦，不同于周围近端尿道的正常毛细血管。
与现有文献和成年对照患者相比，严重下弯患者的尿道板及其下组织的结构与正常尿道不同。缺乏弹性纤维可能有助于解释腹侧阴茎的僵硬导致下弯。平滑肌纤维不规则、无组织的分布提示海绵体发育不良。异常的大血窦可能解释了会阴型和近端型伴严重下弯的患者腹侧阴茎愈合质量差的原因。这可以解释严重下弯患者在使用背侧皮瓣时，后期仍存在/复发下弯的现象。该研究还支持最近的两阶段手术趋势，作为近端型及会阴型伴严重下弯的尿道下裂患者的治疗方案，在初次手术时切除所有发育不良的组织。
