Ch 110 vagina Flashcards
embryology
- external genitalia are initially contiguous with the hindgut, opening at a common cloaca
- the rectum and urogenital sinus are separated by a caudally progressing urorectal septum, forming independent GIT and urogenital systems
- cranial vagina is formed from fusion of the paired paramesonephric (Müllerian) ducts
What kind of epithelium does the vagina have?
Nonglandular, stratified squamous epithelium
oestrus; cornification of epithelial cells on vaginal cytology
What it the blood supply to the vagine, urethra, vestibule and vulva?
Vagina, urethra and vestibule - Vaginal artery (arises from internal pudendal)
Vulva - External pudendal artery
What are the most common commensal organisms of the canine vagina?
E.Coli
B-haemolytic Strep
Staph pseudintermedius
Pasteurella multocida
What sized endoscope can be used for vaginoscopy?
Small dogs and cats 3-5kg - 2.7mm rigid cystoscope with 10Fr sheath
Dogs over 10kg - 4mm scope with 19Fr sheath
contrast vaginourethrogram with CT
List the approaches to the vagina
- Episiotomy
- Ventral approach (pubic symphysiotomy/ectomy)
- Combined abdominal and perineal approach
List the forms of congenital vestibulovaginal stenosis
Focal hypoplasia
Imperforate hymen
Vertical septum
Double vagina
What is the cause of vestibulovaginal stenosis?
Retained epithelial tissue at the point of fusion of the paired paramesonephric ducts in the sagittal plane (vertical spetum) or at the transverse junction of the paramesonephric ducts with the urogenital sinus (imporforate hymen)
What clinical signs may be seen with vestibulovaginal stenosis?
Difficultly or pain associated with breeding
Recurrent vaginitis
Hydrocolpos (fluid accumulation within the vagina)
Recurrent UTIs
Dx - endoscopy, rule out concurrent ureteral ectopia
List the surgical options for vestibulovaginal stenosis
Vertical septa:
- Endoscopic laser ablation (Nd:YAG, Ho:YAG, diode)
- Endoscopic scissors
- Episiotomy with resection of septum at dorsal and ventral attachment
Annular:
- Circumferential partial thickness resection of mucosa and submucosa
- T-shaped vaginoplasty (1/5 had good outcome…)
- Complete resection and anastomosis (decreased fertility)
- Complete vaginectomy (Caudal laparotomy with pelvis osteotomy or episiotomy)
stricture formation at the surgical site
Define rectovaginal fistulas and anovulvar clefts
Rectovaginal fistula: A connection between the rectum and vagina or vestibule, typically assoc with atresia ani
Anovulvar cleft: Failure of fusion between the dorsal urogenital folds leaving a midline defect in the perineal skin that normally seperates the anus and dorsal vulva commisure
atresia ani sx
atresia ani, reconstruction of the anal orifice may be performed by resecting the fistula through a midline perineal approach and closing the vagina and rectal defects using monofilament absorbable sutures placed from the exterior. The blind-ended rectum is then located by incising through the anal dimple, and the rectal mucosa is sutured to the perineal skin
Complications
- fecal incontinence,
- dehiscence
- stricture formation
success rates are fair to good in the small number of reported cases.
What is the surgical treatment of an anovulvar cleft?
Inverted V perineoplasty
Recessed Vulva
Pathophysiology
- recent retrospective study has suggested that ovariohysterectomy has no causative effect on the occurrence of recessed vulvar conformation
- breed and body weight
CS
- 50% dermatitis or vaginitis
- secondary to urine pooling in the vagina, with recurrent UTI 52% to 56% +/- “incontinence”
conservative management with daily cleansing
What is the prognosis for treatment of a recessed vulva with episioplasty?
Resolution of UTI in 84-100%
What is vaginal oedema?
What is the recommended Tx?
ddx prolapse, neoplasia, and clitoral hypertrophy.
- Certain young, femal entire dogs develop a mass of oedematous tissue arising from the ventral floor of the vagina, just cranial to the urethral tubercle, under the influence of oestrogen in late proestrus and oestrus
- Will resolve with termination of oestrus however recurrence is high, OVH is recommended
- Resection of oesematous tissue can be performed if it has become traumatised or in breeding animals
True vaginal prolapse
- distinguished by the “doughnut-shaped” protrusion
- treated by manual reduction followed by ovariohysterectomy (hysteropexy for breeding)
List potential causes of clitoral hypertrophy
Spontanous idiopathic
Exogenous androgens
Intersex conditions
Resolution of signs can be achieved by resection of the clitoris
What are the most common vaginal neoplasias?
73-85% leiomyoma (pedunculated, intraluminal)
Lyomyosarcoma is most common malignant mass
leiomyoma appears hormone related, most in older intact female dogs
sx for benign
episiotomy
What is the surgical options for malignant vaginal tumours?
What is the prognosis?
Vulvovaginectomy and perineal urethrostomy (If entire, also need to approach the abdomen for OVH)
Survival time 9wk-10m
neoplasia extends cranial to the cervix or involves the caudal abdomen, the entire reproductive tract is removed through caudal laparotomy and pubic osteotomy or ostectomy
tuBilateral
pubic and ischial osteotomy in cats offers good exposure for resection of large vaginal masses with minimal postoperative complications
Kate Forster 2023
Histopathological diagnosis included T-cell–rich B-cell lymphoma (n = 1), mycetoma (1), and vaginal polyp (1).
vaginectomies
All 3 cases developed mild pelvic-limb splaying postoperatively; 2 mild stranguria > all resolved
Resection of vaginal septum using
endoscopic-guided sealing devices in
female dogs: 8 cases (2015–2018)
Nicoli and Caccamo 2021
often concurrent with
ectopic ureters in bitches. During endoscopic laser ablation of the ectopic ureter, the vaginal septum
should be cut in the same surgical session. However, sometimes, the septal length and thickness
make the procedure extremely long and challenging with lasers. This study aimed to describe the use
of sealing devices for septal cuts.
allowed a rapid and uneventful resection
of the vaginal septum
The real clinical implications of the various VVSRs are unclear as in some dogs it can be an incidental finding, while it may contribute to urinary incontinence, recurrent bacterial
cystitis, vaginal pooling of urine, recurrent vaginitis,
Outcomes associated with vaginectomy and
vulvovaginectomy in 21 dogs
Jessica A. Ogde
liptak 2020
Multi-institutional retrospective study
Four dogs had vulvovaginectomy, six had
complete vaginectomy, and 11 had a subtotal vaginectomy performed
(10 leiomyomata, three
leiomyosarcomas, two leiomyofibromas).
Major complications requiring revision surgery were
recorded in two dogs (rectal perf). Postoperative UIC occurred in six of 21 dogs (28%), resolving in 3 (14%)
Dogs with malignant tumors (n = 6)
survived at least 71 days (median, 626
recurrence in 2 (30%)
Ovariohysterectomy at the
time of surgery decreases the risk of recurrence for benign
lesions, but whether there is benefit for malignancies is
unknown
