Ectopic Vas Deferens

Abstract

Two infants with ectopia of the vas deferens are described. To date 11 cases have been reported, comprising a total of 13 ectopic vas insertions, 2 of which are bilateral. A classification of 2 types of ectopic vas is presented with a discussion of their relationship to ureteral ectopias. An embryological hypothesis of a proximal vas precursor segment of the wolffian duct is related closely to Stephens' theory of ureteral development.

The ejaculatory duct ectopically invading the bladder with multiple congenital malformations of the homolateral urogenital system: a report of a rare case and an embryological review

“…In the same year, a case report by Tanagho [9] also supported Mackie's theory. Subsequently, on the basis of Mackie and coworkers [8] and Tanagho's [10] theory, Gibbons et al [11] put forward the concept of a deferent duct precursor to illuminate the embryological principle for seminal passage allotropically invading the urinary tract.…”

“…Normally, when the common mesonephric duct (CMD) forms the bladder trigone, PVP enters the vesicourethral canal at the place of the seminal crest and continues to develop into the ejaculatory duct, the seminal vesicle and the proximal part of the deferent duct ( Figure 4A) [11]. Gibbons et al [12,13] hypothesized that the ejaculatory duct would ectopically invade or open towards the urinary tract if the PVP intruded into the CMD, and that the intruded position of PVP decided the site of the ectopic ejaculatory duct orifice.…”

“…The embryonic-development schematic diagrams of the urogenital system [11]. (A): PVP enters the vesicourethral canal at the place of the seminal crest.…”

“…ves., seminal vesicle; UB: ureteric bud; UGS: urogenital sinus. npg position of the UB emanating from the CMD ( Figure 4B) [11,12].…”

Ectopic vas deferens opening into the ureter

“…1 The vas was transplanted along with the left ureter in a transverse fashion (Cohen), expecting future retrieval of sperm from the bladder. Two leading embryological explanations were discussed, one proposed by Gibbons,2 in which ectopia and an abnormality of the proximal vas precursor relative to the ureteral budding zone in the common mesonephric duct was implied to play a central role, and another by Schwarz and Stephens, 3 which regards this anomaly rather as the persisting mesonephric duct resulting from an abnormality in the ureteral budding zone relative to the mesonephric duct. 4 Hopefully, molecular probes and evolving studies using the knockout mouse model 5 will enlighten our understanding of the pathogenesis of congenital anomalies of the kidney, ureter and seminal tract.…”