title: Wolffian Origin of Vagina Unfolds the Embryopathogenesis of OHVIRA (Obstructed Hemivagina and Ipsilateral Renal Anomaly) Syndrome and Places OHVIRA as a Female Counterpart of Zinner Syndrome in Males.
abstract: BACKGROUND
  The classical theory of Müllerian origin of upper vagina fails to explain complex urogenital malformations like OHVIRA syndrome; the Acien's hypothesis, however, unravels the hidden embryopathogenesis. As per Acien, Wolffian (mesonephric) ducts instead of Müllerian ducts and sinovaginal bulbs, give rise to the vagina. The new hypothesis, however, retains the concept of origin of the ureters (with ureters inducing renal development) by the former and the uterus by Müllerian ducts. Thus, a failure of development of mesonephros/mesonephric duct gives rise to absent ureters and hence absent homolateral kidney; blind ending (obstructed) ipsilateral hemivagina and cessation of support to paramesonephric ducts which leads to unfused uterus (uterus didelphys). Hence, the new hypothesis explains all components of OHVIRA syndrome. On a parallel track, unilateral anomalous development of the mesonephros in males causes atresia of the homolateral ejaculatory duct that results in obstruction of the proximally placed seminal vesicle. Besides, there is absence of the ipsilateral kidney (Zinner syndrome).
  
  
  METHODS
  In this manuscript, we describe four cases of OHVIRA syndrome. Case 1 was a 34-year-old nulligravida, married since fourteen years, who presented with a 5-month history of pelvic inflammatory disease and dyspareunia. Regular menses in the patient and azoospermia in her husband delayed the diagnosis. Case 2 was a 14-year-old girl who presented with dysmenorrhea and lower abdominal pain since a few months. Case 3 was a 27-year-old female who presented with infertility and dysmenorrhea. Case 4 was a 15-year-old female who presented with a one-year history of dysmenorrhea and cyclic pelvic pain. In all cases, one of the uterine horns revealed collection due to a hemivaginal septum and an absent ipsilateral kidney; thus, establishing the diagnosis of OHVIRA syndrome. The case 4 additionally revealed homolateral vaginal agenesis.
  
  
  CONCLUSIONS
  On the basis of our 4 cases, we support the Acien's hypothesis of Wolffian origin of vagina which explains the development of OHVIRA syndrome. Besides, we emphasize the need to suspect this syndrome in a female with a pelvic mass and absence of homolateral kidney. Finally, we believe that OHVIRA due to its Wolffian origin is a female equivalent of Zinner syndrome in males. Therefore, we proposeOSVIRA (Obstructed Seminal Vesicle and Ipsilateral Renal Agenesis) as an acronym for Zinner syndrome analogous to OHVIRA.
authors.affiliation: Department of Radiology, Topiwala National Medical College & BYL Nair Charitable Hospital, Mumbai Central, Mumbai, India.
authors.forename: Yashant
authors.initials: Y
authors.lastname: Aswani
authors.affiliation: Department of Radiology, Topiwala National Medical College & BYL Nair Charitable Hospital, Mumbai Central, Mumbai, India.
authors.forename: Ravi
authors.initials: R
authors.lastname: Varma
authors.affiliation: Kuchaman Imaging and Diagnostic Centre, Nagaur, Rajasthan, India.
authors.forename: Pradeep
authors.initials: P
authors.lastname: Choudhary
authors.affiliation: Department of Radiodiagnosis, M.P. Shah Medical College, Jamnagar, Gujarat, India.
authors.forename: Reeta B
authors.initials: RB
authors.lastname: Gupta
keywords: Dysmenorrhea; Hematocolpos; Infertility; Mullerian Ducts; Wolffian Ducts