Baskin L S, Erol A, Li Y W, Cunha G R
Department of Urology, University of California School of Medicine, San Francisco 94143-0738, USA.
J Urol. 1998 Sep;160(3 Pt 2):1108-15; discussion 1137. doi: 10.1097/00005392-199809020-00039.
Hypospadias is the most common congenital anomaly affecting the penis. Successful repair depends on an accurate understanding of anatomy. We compared the anatomy of hypospadiac and normal fetal penises.
A fetal penis at 33 weeks of gestation with distal shaft hypospadias was serially sectioned and compared to 10 normal human fetal specimens at 8 to 32 weeks of gestation. Immunohistochemical localization was performed with S-100 protein and protein gene product 9.5 to localize neurons. Blood vessels were localized by the presence of red corpuscles, and immunohistochemical staining with von Willebrand's factor and factor VIII. Three-dimensional computer reconstructions of the nerves, corporeal bodies, tunica and urethra of the hypospadiac and normal fetal penises were compared.
Except at the region of the abnormal urethral spongiosum and glans, the hypospadiac and normal penises showed no difference in neuronal innervation, corpora cavernosa and tunica albuginea architecture and blood supply. The nerves started proximally as 2 well defined bundles under the pubic rami superior and slightly lateral to the urethra. As the 2 crural bodies converged into the corpora cavernosa, the nerves diverged, spreading around the cavernous bodies up to the junction with the urethral spongiosum without remaining at the 11 and 1 o'clock positions. Along the entire shaft of the penis there were no neuronal structures at the 12 o'clock position. The most striking difference was in vascularity. In the hypospadiac penis factor VIII immunostaining revealed huge endothelial lined vascular channels filled with red blood cells. In contrast, the normal penis had well defined small capillaries around the urethra that fanned out into the glans. Vascularity was also extensive under the urethral plate. Nerve distribution in the abnormal glans was also less extensive than in the normal penis.
Increased knowledge of normal and hypospadiac penile anatomy with respect to the nerves, corporeal bodies, glans and vascularity is useful for the strategic design of penile reconstructive procedures.
尿道下裂是影响阴茎的最常见先天性异常。成功修复取决于对解剖结构的准确理解。我们比较了尿道下裂胎儿阴茎与正常胎儿阴茎的解剖结构。
对一名妊娠33周患有阴茎体远端尿道下裂的胎儿阴茎进行连续切片，并与10例妊娠8至32周的正常人类胎儿标本进行比较。用S-100蛋白和蛋白基因产物9.5进行免疫组织化学定位以定位神经元。通过红细胞的存在以及用血管性血友病因子和因子VIII进行免疫组织化学染色来定位血管。比较了尿道下裂胎儿阴茎与正常胎儿阴茎的神经、海绵体、白膜和尿道的三维计算机重建图像。
除了异常尿道海绵体和龟头区域外，尿道下裂阴茎与正常阴茎在神经支配、海绵体和白膜结构及血液供应方面无差异。神经起始于耻骨支下方、尿道稍外侧的2个界限分明的束。随着2个脚状海绵体汇聚成海绵体，神经分开，围绕海绵体扩散直至与尿道海绵体的交界处，而不会停留在11点和1点位置。沿阴茎整个体部，12点位置没有神经结构。最显著的差异在于血管分布。在尿道下裂阴茎中，因子VIII免疫染色显示有充满红细胞的巨大内皮衬里血管通道。相比之下，正常阴茎在尿道周围有界限分明的小毛细血管，这些毛细血管呈扇形延伸至龟头。尿道板下方的血管分布也很广泛。异常龟头中的神经分布也比正常阴茎少。
增加对正常和尿道下裂阴茎在神经、海绵体、龟头和血管方面解剖结构的了解，有助于阴茎重建手术的策略性设计。
