Absence/aplasia of the vulva with atresia of the vestibular opening in a dog

10-months-old, neutered female Pinscher. Physical examination: she has neither penis nor vulva; however, the presence of a uterus was confirmed. History of dysuria. An ovariohysterectomy was performed, and an incision was made in the urethral outlet to facilitate the passage of urine. Now she has dysuria again and accumulation of fluid around the stenosed hole of the urethra.
An abdominal CT scan was performed.

Description

Absence of labia and vulva. There is a marked distension of the vagina and vestibule with hypoattenuating content and a thin hyperattenuating wall that enhances after contrast administration. These changes extend caudally, protruding and herniating between the soft tissues of the perineal area, with the vestibule appearing at subcutaneous level (orange arrows). There is a discreet irregularity on the surface of the most caudoventral aspect of the vestibule, without any obvious opening to the outside. The distention produces a mass-effect with compression of the rectum dorsally and of the urethra ventrally.

Dog CT scan aplasia of the vulva

The urinary bladder is moderately distended, with hypoattenuating content and homogeneous wall. The urethra is completely visible, showing a slightly thickened wall that enhances after contrast administration (green arrows). The urethrovestibular junction/urethral opening has a normal appearance, located dorsal to the caudal aspect of the pubis and 4.5 cm from the most caudal aspect of the vestibule, adjacent to the skin (pink arrows).

Dog CT scan external urethral orifice
Dog CT scan external urethral orifice and urethral wall
Dog Ct aplasia of the vulva
Doc CT scan external urethral orifice

Diagnosis

  • Absence/aplasia of the vulva with atresia of the vestibular opening towards the outside, consistent with a congenital malformation.
  • Vestibule-vaginal distension, possibly filled with urine due to obstruction and stenosis at the level of the opening, secondary to the previous surgery.

Comments

In this case, it is complicated to differentiate between pre- and post-surgical alterations. However, there seems to be a malformation at the level of the caudal urogenital tract, and stenosis of the previously performed opening.

No comment yet, add your voice below!


Add a Comment

Your email address will not be published. Required fields are marked *