Vaginal Atresia

Vaginal atresia is a condition in which part of the vagina fails to canalize and is therefore closed or absent. It occurs in about 1 in 5,000 births.

The most common cause is abnormal development of the urogenital sinus which contributes to the formation of most of the lower third of the vagina. Congenital vaginal atresia is a distinct condition from vaginal agenesis in that the upper vagina and female reproductive structures intact in the former, because the differentiation of Mullerian organs is unaffected.

There are many grades, ranging from complete vaginal hypoplasia to a vaginal obstruction such as that caused by an imperforate hymen or transverse vaginal septum, or atresia of the lower third of the vagina. Acquired vaginal atresia is rare but may follow the occurrence of inflammation, tumors or trauma to the vagina.

Since vaginal atresia is much rarer than vaginal agenesis, most medical classification systems do not consider or include it in their categories. The American Fertility Society (AFS) puts complete vaginal atresia under the heading of Mullerian agenesis/dysgenesis.

Presentation

Vaginal atresia presents most commonly with primary amenorrhea in a girl with a normal XX genotype, ovarian and hormone function. In other patients, it may present with cyclical abdominal pain. Both presentations are due to the retention of menstrual flow within the upper vagina, leading to hematocolpos. The lack of an introitus which is replaced by a vaginal dimple is pathognomonic of this condition.

Differential diagnosis of the condition includes vaginal agenesis, androgen insensitivity syndrome, imperforate hymen, labial adhesions, and transverse vaginal septum.

Cyclic pelvic pain and primary amenorrhea are the presenting features in girls with normal genotype, normal ovarian function and normal hormone levels.  No introitus and presence of vaginal dimple are pathognomonic.

Imaging is diagnostic, with ultrasound or magnetic resonance imaging (MRI), revealing the presence of a normal uterus and cervix, normal ovaries and fallopian tubes, and a large hematocolpos.

Treatment

There is no single approach which is universally successful in treating all grades of this condition but some options are as follows:

Dilatation Procedures

Dilation procedures are recommended as first-line treatment for lower grades. These are based upon tissue expansion but are not suitable in the presence of skin scarring as may follow previous surgery. They include:

• Intermittent self-dilation or Frank’s procedure using a graduated series of vaginal dilators which are inserted into the vaginal dimple using pressure, to expand the potential space between the rectum and bladder.
• Vecchietti procedure which uses continuous traction with an ovoid vaginal bead pulled upwards using abdominal traction, achieves good results within a few days as compared to months. It may be done by laparoscopy or laparotomy.

Surgical Procedures

• Vaginal pull through procedure which involves cutting through the obstructing fibrous material, such as an imperforate hymen or transverse vaginal septum, until the normal vagina is reached. At this point the collected blood is drained. The normal mucosa is then pulled through and attached at the hymeneal ring just above the introitus, and kept patent until re-epithelialization occurs.
• William’s vaginoplasty in which the labia majora are fused to form a short neovagina. It results in a very short vagina, however, which is unsatisfactory in the majority of patients, and therefore various modifications have been made to the technique.
• McIndoe-Reed procedure uses a split-thickness skin graft to line the neovaginal space created by expanding the potential space in the rectovesical fascia.
• Davydov procedure uses the same space lined by peritoneum.

These procedures employ a variety of techniques and tissues to create a functional and cosmetically acceptable vagina. They may be based upon split-thickness skin grafts, full-thickness skin grafts, amniotic membrane, bowel grafts, or peritoneum. Each has its advantages and disadvantages, but many of them have now been replaced by laparoscopic procedures. This makes them less invasive, with shorter recovery times and avoids large abdominal incisions, potentially averting many operative complications. It also helps to prevent adhesions and rectal injury. Robotic surgery is now becoming increasingly used.

References

• https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3513253/
• http://www.gpnotebook.co.uk/simplepage.cfm?ID=-382402518
• https://fertilitypedia.org/edu/diagnoses/gynatresia#/Fertilitypedia-description
• https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1825430/pdf/canmedaj00693-0077.pdf
• http://www.tandfonline.com/doi/abs/10.1080/01443610252971285
• https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4518385/
• http://onlinelibrary.wiley.com/doi/10.1111/j.1471-0528.2007.01547.x/full
• Callahan, T. L., & Caughey, A. B. (2009). Blueprints obstetrics & gynecology. Philadelphia: Wolters Kluwer Health/Lippincott William & Wilkins.
• Nucci, M. R., Oliva, E., & In Goldblum, J. R. (2009). Gynecologic pathology: A volume in the series foundations in diagnostic pathology. Edinburgh [etc.: Churchill Livingstone.