18. Urogenital Surgery in the Mare

What muscles make up the vulva?

Paired constrictor vulvae mm.

What TWO things make up the vestibule?

•Paired constrictor vestibuli mm.

•Vestibular sphincter

What are some devices/things you can do to preform and internal exam of the repro tract of the horse?

•Endometrial biopsy, culture, and cytology

•Palpation and ultrasound

What are some contributing factors that may predispose a mare to needing urogenital surgery?

-Conformational defects

-Breeding programs

-Trauma

What term is described by aspiration of air/debris into reproductive tract it isalso known as wind-sucking?

Pneumovagina

What is the etiology behind Pneumovagina?

Poor perineal conformation

What are some instances that can lead to poor perineal conformation?

•Multiparous mares

•Poor body condition

•Sinking of anus (splanchnoptosis)

•Relaxation of perineum during estrus

T/F Pneumovagina can lead to chronic inflammation adn infection, which in turn leads to reduced fertility

True

What are THREE surgical techniques that can be used to correct Pneumovagina?

-Vulvoplasty (Caslick's procedure)

-Perineal body reconstruction

-Perineal body transection

What broadly happens in a vulvoplasty?

Labia sutured together to the level of the ischial arch

How would you describe the Vulvoplasty procedure?

•Local infiltrated into labial margins

•__-__ __ wide strip of mucosa excised from mucocutaneous junction

Closed with 2-0 or 0 suture in _____ _____

4-8 mm, continuous pattern

What continuous pattern is typically used to close a Caslick?

Ford interlocking

When should you remove the sutures from a Vulvoplasty?

10-14 days

If you excessively close the vaginal opening, what may this result in?

splash-back"of urine during voiding and urovagina

Vulvoplasty should be opened (episiotomy) ____ weeks before foaling date

two

What condition has names such as Vesicovaginal reflux and Urine pooling?

Urovagina

What is the common etiology of urovagina? (4)

-Poor perineal conformation

-Ectopic ureter

-Cystitis

-Urolithiasis

What are the TWO procedures that you can do to do to correct Urovagina?

-Caudal relocation of transverse fold

-Urethral extension

What are the guidedlines for •Urethral extension?

-Catheter maintained for 2-3 days

-Post-op antibiotics and anti-inflammatories

-Recheck 2-3 weeks

- Sexual rest for 4-6 weeks

What is an uncommon developmental anomaly that is an imperforate membrane between the vagina and vestibule?

Persistent hymen

How do you fix a persistent hymen?

Bluntly perforated and accumulated secretions removed via lavage

What are THREE common foaling issues that lead to surgical management?

-Perineal lacerations

-Rectovestibular/vaginal (RV) fistulas

-Cervical injuries

What are some problems that can lead to perineal lacerations? (2)

•Unassisted foalings

•Primiparous mares

What are THREE issues that can lead to primiparous mares?

•Prominent vestibular sphincter

•Forefeet catch in dorsal aspect of sphincter

•Abdominal press forces foot through vestibule

What is tore in a first degree perineal laceration?

-Mucosa of vestibule

-Skin of dorsal commissure of the vulva

T/F A first degree perineal laceration typically needs surgery

Fasle, does not

What are THREE muscles/structures that are affected in a second degree perineal block?

-Vestibular mucosa and submucosa

-Muscles of the perineal body

Constrictor vulvae muscle

What are THREE sequelae that are associated with constrictor vulvae muscle?

-Sunken perineum

-Pneumovagina

-Urovagina

If a mare has a second degree perineal laceration, what surgeries need to be done?

surgical reconstruction of perineal body and vulvoplasty

What are FOUR circumstances that will cause a 3rd degree perineal tear?

-Excitable primiparous mares

-Fetal oversize

-Fetal malposition

-Aggressive assistance

What are the changes that occur in a third degree perineal tear?

-Penetration into rectum

-Rectovestibular shelf disrupted

- RV fistula

What are the THREE structure that makes up the Rectovestibular shelf?

•Perineal body

•Anal sphincter

•Dorsal commissure of vulva

T/F RV fistula results if foaling is assisted and foals limb is replaced within the vestibule

True

In a third degree perineal tear, all issues need surgical intervention. What are the issues that need surgery?

•Re-establish tissue shelf and functional perineal body

•Initial medical treatment

•Delayed surgical repair

T/F With perineal tears, you need to get them to surgery ASAP

False, -DO NOT ATTEMPT IMMEDIATE REPAIR

How long should you delay the surgical repair of perineal laceration?

3-4 weeks

If you decide to surgically repair the perineal laceration the feces must be soft. How do you make this happen?

•Maintain on lush pasture

•Wet bran mashes

•Laxatives (mineral oil, MgSO4)

What is the post op care for peroneal lacerations?

-Post-op antibiotics and anti-inflammatories

-Recheck 2-3 weeks

-Sexual rest for 4-6 weeks

What are TWO complications that can arrise from perineal lacerations?

•Fistula formation

•Complete dehiscence

What are the TWO etiologies of an RV fistula formation?

-Foaling injury

-Failure of 3rd degree perineal laceration repair to heal

What are the THREE techniques for correcting a RV fistula?

-Conversion to 3rd degree perineal laceration

-Horizontal approach through perineal body

•Fistulas located more cranially (deeper)

T/F If there is a 3rd degree perineal laceration, the fistula is located crainially

False, caudally

What structue os approximately 5-7.5 cm in length and 3-5 cm wide

and composed of mucosal and muscular layers?

Cervix

What is the major function of the cervix in the mare?

functions as the third physical barrier of the uterus

What can happen to the cervix due to excessive or abrupt stretching during foaling and inadequate relaxation?

cervical laceration

When are cervical lacerations more likely to occur?

during dystocia/induced parturition

What are the clinical signs of a laceration?

•Persistent infertility

•Endometritis

•Early fetal abortion

T/F Not all lacerations will interfere with fertility or maintenance of pregnancy

True

When should you evaluate the cervix on palpation?

•30 days following parturition

•During diestrus

What is the minimal amount of days that need to pass to consider surgery? When should you try to repair bc it is ideal?

30 days, 60 days

What phase of the cycle should you preform cervical laceration repair and why?

-diestrus when the cervix is contracted and tight

What is the post op care for cervical tear?

-Steroid/antibiotic ointment application

-Sexual rest for two heat cycles

-Artificial insemination

-Breeding roll to prevent deep penetration by the stallion

-Inform owner that repair may be necessary following subsequent foalings

What issue can cause the followin?

-Can prevent opening

-Can prevent closing

-Occlusion of the lumen

-Manual palpation

-Adhesion excision

-Topical steroid ointment

Luminal stent

Cervical adhesion

What anatomical structure is 70-80mm long, 40-60mm wide, and kidney shaped with prominent ovulatory fossa?

ovary

What is the blood supply of the ovary?

•ovarian branch of ovarian artery

What structure suspends the ovary?

Cranial attachment of broad ligament (mesovarium)

What are TWO indications for ovary surgery?

•Ovarian tumors

•

•Behavior problems

•

What is the most common ovarian neoplasia that stems from the sex cord stromal cells and is usually UNILATERAL enlarged and the contralateral ovary is atrophied?

Granulosa cell tumor (GCT)

What are the clinical signs of GCT? (4)

•Anestrus

•Continuous estrus

•Nymphomania

Stallion-like behavior

What are the THREE ways to evaluate a GCT?

•Palpation and ultrasound

•Serum concentrations of inhibin and testosterone may be elevated

•Serum anti-mullerian hormone

What is the most sensitive assay for a GCT?

Serum anti-mullerian hormone

What is needed for the definitive diagnosis of a GCT? What surgical procedure is indicated?

Histopathological evaluation, Ovariectomy

What are some indication of neoplasia on pathology?

-Cystic structures

-Hematomas

Abscesses

What are the THREE surgical approaches to ovarian neoplasia removal?

-Flank incision

-Colpotomy

- Laparoscopic

What are some methods for mesovarium hemostasis?

-Emasculator (écraseur)

-Suture ligatures

-Stapling devices/hemoclips

-Polyamide tie-rap

-Laser dissection

- Electrosurgical instruments (LigaSure™

If you are doing a Standing laparoscopic procedure, how long should you with hold food for?

24-36 hours

What should you use to sedate for a standing procedure?

Detomidine

What is the post op care for ovarian neoplasia removal?

•Tapering course of NSAIDs

•

•Perioperative antibiotics

•

•Stall rest with hand-walking for 2 weeks