Vagina, vestibule and vulva

Question 1

What was the rate of urinary incontinence following vaginectomy or vulvovaginectomy in a study by Ogden 2020 in Vet Surg? What were the most common tumours diagnosed?

Answer 1

Six of 21 dogs (spontaneously resolved in 3).

Smooth muscle tumours were the most commonly diagnosed.

Question 2

What device was used for the successful transection of vestibulovaginal septal remnants in female dogs in a study by Nicoli 2022 in JSAP?

Answer 2

Endoscopic guided bipolar vessel sealing devices (Enseal and Ligasure).

Question 3

What were the four types of vestibulovaginal malformations in dogs as described by Nicoli 2022 in JSAP?

Answer 3

Imperforate hymen: thin “string” of tissue and can be digitally perforated.

Persistent paramesonephric remnant: membrane in which the tissue extends cranially from the vestibulovaginal junction <1 cm

Vaginal septum: membrane in which the tissue extends cranially >1 cm stopping before the cervix.

Dual vagina: tissue extends from the vestibulovaginal junction to the cervix, splitting the vagina into two compartments.

Question 4

What demarcates the vestibulovaginal junction?

Answer 4

A transverse, palpable mucosal ridge and transition from light pink, redundant vaginal mucosal folds to smooth, red vestibular mucosa.

Question 5

What is the vascular supply to the vagina?

Answer 5

Branches of the vaginal artery. The vulva is supplied by branches of the external pudendal artery.

Venous drainage mirrors arterial supply.

Question 6

What is the lymphatic drainage of the vagina, vestibule and vulva?

Answer 6

Vagina/vestibule: internal iliac LNs.
Vulva: superficial iliac LNs.

Question 7

What are the most common bacterial isolates in the normal canine vagina?

Answer 7

E.coli, strep, staph and pasteurella.

Question 8

When are the presence of large numbers of neutrophils on vaginal cytology considered pathologic?

Answer 8

Should only be seen in large numbers during diestrus. Therefore abnormal in spayed dogs or in any dog if degenerative.

Question 9

Describe the surgical approach for episiotomy.

Answer 9

Question 10

Describe the ventral approach to the vagina

Answer 10

Question 11

Name the following development anomalies of the vestibulovaginal junction.

Answer 11

Question 12

What developmental abnormality is responsible for vaginal septum?

Answer 12

Failure of fusion of the paired paramesonephric ducts.

Question 13

What developmental abnormality is responsible for imperforate hymen?

Answer 13

Failure of fusion of the paramesonephric ducts and the urogenital sinus.

Question 14

What are some clinical signs associated with vestibulovaginal stenosis?

Answer 14

Difficulty or pain associated with breeding, recurrent vaginitis, hydrocolpos (fluid accumulation in the vagina), or recurrent urinary tract infections.

Urinary incontinence unlikely to be primarily caused by these defects.

Question 15

How is vestibulovaginal stenosis diagnosed?

Answer 15

Vaginal examination, contrast radiography, vaginoscopy.

Question 16

What are some surgical techniques described for correction of vestibulovaginal stenosis?

Answer 16

1. Septa:
   a. If thin can be performed via vaginoscopy using an Nd:YAG or diode laser resection or endoscopic scissors.
   b. Blind retraction and resection using a spey hook.
   c. Open approach via episiotomy and transection with primary mucosal repair.
2. Annular lesions: generally performed via episiotomy - partial thickness excision and repair of mucosa/submucosa, transverse closure of longitudinal incision (T-shaped vaginoplasty), partial vaginal resection and anastomosis, complete vaginectomy.
3. Extensive lesions or stenoses more than 2cm cranial to the vestibulovaginal junction: vaginal resection and anastomosis (via pubic flap or symphyseal osteotomy) or complete vaginectomy (caudal midline laparotomy, pelvic osteotomy, episiotomy after OVH).

Question 17

What condition are rectovaginal fistulas commonly associated with?

Answer 17

Atresia ani

Question 18

What condition and surgical technique is depicted?

Answer 18

Question 19

What is the cause of an anovulvar cleft? What is the surgical treatment?

Answer 19

Failure of closure of the dorsal urogenital folds.

Surgical repair is performed via an inverted V-perineoplasty.

Question 20

What influences the occurrence of recessed vulva?

Answer 20

Breed and body weight (OVH has no effect on the likelihood of recurrence).

Medium and large breed dogs are more frequently affected.

Question 21

What are the clinical signs associated with recessed vulva?

Answer 21

Perivulvar skin fold dermatitis or vaginitis (50%), recurrent UTI (52-56%), apparent urinary incontinence (56%, likely due to urine pooling).

Question 22

What is the surgical treatment for recessed vulva?

Answer 22

Episioplasty (or vulvoplasty)

Question 23

What is the most common complication of episioplasty?

Answer 23

Complications are rare but may include dehiscence if surgical resection is aggressive.

Outcome is typically excellent with resolution of UTI in 84-100% of dogs.

Question 24

What is vaginal edema?

Answer 24

Mass of edematous tissue that forms on the ventral floor of the vagina just cranial to the urethral tubercle secondary to estrus/proestrus.

Much more common that vaginal prolapse, and can be differentiated from this disease by vaginal examination.

Question 25

How is vaginal edema treated?

Answer 25

Conservative management with lubricant and e-collar is recommended until the resolution of estrus. OVH is ideal as recurrence is likely.

In breeding animals or if mucosal damage is significant resection of the mass can be performed at the level of the submucosa.

Question 26

How is vaginal prolapse treated?

Answer 26

Reduction and OVH. If other organs are herniated concurrently may require cystopexy or colopexy.

Question 27

What are potential causes of clitoral hypertrophy?

Answer 27

Spontaneous, exogenous androgen administration, intersex conditions.

Question 28

What is the treatment of clitoral hypertrophy?

Answer 28

Clitoral resection. In intersex dogs care must be taken to ensure that the urethra does not end in association with the clitoris (os penis rather than os clitoris) requiring urethral reconstruction.

Question 29

What percentage of vaginal and vulvar neoplasms are benign?

Answer 29

73-84%

Question 30

What is the most common neoplasia of the vagina or vulva?

Answer 30

Leiomyoma. Leiomyosarcoma is the most common malignancy.

Question 31

What are surgical treatment options for vaginal/vulval neoplasia?

Answer 31

Benign, pedunculated vaginal neoplasia: episiotomy and full thickness resection with 2 layer closure.

Malignancies caudal to the cervix: vulvovaginectomy and perineal urethrostomy through a caudal approach.

Malignancies extending cranial to the cervix or involving the caudal abdomen: complete removal of the reproductive tract via caudal laparotomy and pubic osteotomy or simultaneous abdominal and perineal approaches.