Chapter 63 - Uterus and ovaries Flashcards
What is the approximate size of the mare’s ovaries?
70-80 mm long and 40-60 mm wide.
How does the size of the mare’s ovaries vary?
It varies with the season and estrous cycle stage.
What is the ovulation fossa, and where is it located?
A palpable indentation on the ventral free border of the ovary.
What structure attaches to the dorsal border of the ovary?
The mesovarium, part of the broad ligament.
What does the mesovarium contain?
Blood vessels, nerves, and smooth muscle fibers.
Which artery provides blood supply to the ovary?
The ovarian branch of the ovarian artery.
How does the oviduct connect to the ovary?
The funnel-shaped infundibulum loosely attaches around the ovulation fossa.
What are the parts of the oviduct from ovary to uterus?
Infundibulum, ampulla, and isthmus.
Where does the isthmus of the oviduct enter the uterus?
At the tip of the uterine horn at the tubal papilla.
How is the uterine body positioned within the mare’s anatomy?
The majority is in the peritoneal cavity; the caudal part is retroperitoneal.
What ligament suspends the uterus in the caudal abdomen?
The broad ligament, also called the mesometrium.
Which vessels supply blood to the uterus?
The uterine branch of the vaginal artery, the uterine artery, and the uterine branch of the ovarian artery.
Which diagnostic tools are commonly used to evaluate the reproductive tract?
Palpation, ultrasonography, hysteroscopy, and blood work.
How long should food be withheld prior to a laparotomy?
12 to 36 hours.
What perioperative medications are commonly given before reproductive tract surgery?
Antibiotics and anti-inflammatory drugs.
Why might withholding food increase health risks in horses?
It can disrupt the diet and increase the risk of colic or diarrhea.
What type of anesthesia is needed for standing surgery on the cranial reproductive tract?
Sedation, visceral analgesia, and local anesthesia.
What anesthetic protocol is recommended for mares in dystocia requiring a cesarean section?
Total intravenous anesthesia with guaifenesin, ketamine, and detomidine until foal delivery.
What is the preferred anesthetic for maintenance during a C-section?
nhalation anesthesia (e.g., isoflurane in oxygen).
What approach is typically used for a flank laparotomy?
A modified grid approach with a vertical line block.
Where is local anesthesia administered for a flank laparotomy?
A 20-cm vertical line halfway between the last rib and the tuber coxae.
What muscles are separated in a flank laparotomy approach?
Internal abdominal oblique and transversus abdominis muscles.
What is the primary purpose of the ventral laparotomy approach?
To provide access to the ovaries or uterus under general anesthesia.
What anesthesia combination is preferred for inducing anesthesia in dystocia cases?
Xylazine, diazepam (or midazolam), and ketamine.
What alternative local anesthetic technique can be used for the paralumbar fossa?
An inverted L block to desensitize the paralumbar fossa.
Describe the layers from skin to the last interior layer of the abdomen
A vertical incision is made through the skin and subcutaneous
tissue, then extended deeper through the external abdominal
oblique muscle and its aponeurosis. The internal abdominal
oblique and transversus abdominis muscles are bluntly separated
parallel to their muscle fibers. The peritoneum is bluntly penetrated
to gain access to the abdomen. This approach is also
used by some to assist a laparoscopic ovariectomy
How are equine ovarian tumors classified?
By tissue type: surface germinal epithelium, sex cord-stromal tissue, and germ cell origin.
What is the most common type of ovarian tumor in mares?
Granulosa cell tumor (GCT)
What percentage of equine reproductive tract tumors are GCTs?
Approximately 85%.
List three behavioral changes observed in mares with GCTs.
anestrus
nymphomania (continuous estrus)
stallion like behavior
What is the typical age of mares affected by GCTs?
11 years old
Are granulosa cell tumors typically benign or malignant?
Usually benign but may occasionally metastasize.
Which hormone levels are frequently elevated in mares with GCTs?
Testosterone and inhibin.
How do GCTs typically appear on an ultrasound?
They are often multicystic structures.
What is the primary diagnostic marker for GCTs in mares?
Anti-Müllerian hormone (AMH).
What sensitivity did AMH testing show in detecting GCTs in a study?
98% sensitivity.
Which ovarian tumor is often found in juvenile horses and can cause hemoabdomen?
Juvenile granulosa cell tumor (GCT).
What is the significance of performing a colpotomy during diestrus or anestrus?
The blood supply to the ovary is at resting levels, resulting in smaller vessel diameters.
What nonneoplastic conditions may cause ovarian enlargement?
Hematomas, cysts, and abscessation.
What is the preferred treatment for a mare with an ovarian tumor?
Ovariectomy.
In what reproductive stage is colpotomy ideally performed?
During diestrus or anestrus.
Why is the mare kept standing for 2-3 days post-colpotomy?
To prevent eventration (prolapse of abdominal contents).
What is the purpose of using an écraseur in a colpotomy?
To crush the ovarian vasculature, providing hemostasis.
Which postoperative care is recommended to prevent ascending infections after colpotomy?
Placing a Caslick suture.
List two complications that can arise after a colpotomy.
Fatal hemorrhage and eventration.
What additional technique is combined with colpotomy in hand-assisted laparoscopic ovariectomy?
The use of laparoscopic portals in the left paralumbar fossa.
What anesthesia method is used for laparoscopic-assisted colpotomy?
Local anesthetic infiltration under laparoscopic guidance.
Why might it be challenging to remove both ovaries via left-sided laparoscopy in larger horses?
Due to instrument length limitations.
What surgical technique allows transvaginal access for colpotomy closure?
Using a Caslick speculum for access.
Which suture pattern is used for closing the colpotomy incision in laparoscopic-assisted ovariectomy?
A continuous suture pattern.
Which ovary is removed first in the laparoscopic-assisted colpotomy procedure described?
The left ovary.
What complication is associated with failure to properly manage ovarian pedicle bleeding?
Excessive or potentially fatal bleeding.
For ovariectomy by colpotomy you place the mare in the stocks, sedate and..
Place epidural, rectum evcuated, bladder is cathterized, tail is tied upward and perineal region is prepared, vaigna is lavaged with dilute povidone iodine solution
In colpotomy where do you do the incision?
cranial to the cranial fornix is critical and 1 to 2 cm incision through the cranial vaginal wall
4 to 5 cm caudolateral to the cervix.
Position is 2 or 4’ clock or at the 8 or 10 o’clock poisition of the cranial aspect of the vagina
Why inicision site of the colpotomy is so important?
These sites avoid inadvertent penetration of the:
bladder,
rectum,
and uterine branch of the urogenital artery laterally.
once you passe the peritoneum in colpotomy and you inserted you hand and find the ovarium what is the next step?
lidocaine-soaked gauze sponge, tethered with a long strand of umbilical tape, is introduced into the abdomen and held around the ovarian pedicle for 1 minute. The chain loop of the écraseur is placed around an ovary, with care taken to exclude other tissues such as intestine, intestinal mesentery, and the tip of the uterine horn. The écraseur is slowly (over 3–4 minutes) tightened until the ovary falls into the surgeon’s hand. Hemostasis is provided by the écraseur crushing the vasculature and subsequent vasoconstriction. The ovary is removed from the abdomen and the procedure is repeated to remove the contralateral ovary.
are you obliged to close the colpotomy site?
The vaginal incision is allowed to heal as an open wound and the mare is kept standing for 2 to 3 days to prevent the rare case of eventration or closure of the colpotomy using absorbable sutures will aid in the prevention of eventration
Name the complications of colpotomy
fatal hemorrhage from laceration of
- uterine branch of the urogenital artery, excessive (possibly fatal) - bleeding from the ovarian pedicle,
- eventration through the vaginal surgery site,
-septic peritonitis,
-abscessation or
-hematoma formation at the incision sites, and
- adhesions of abdominal viscera to the incision sites
how do you perform the laparoscopic assisted colpotomy technique?
two laparoscopic portals in the left paralumbar fossa and made a colpotomy incision under laparoscopic guidance. A chain écraseur inserted via the colpotomy was used to remove the left ovary. Laparoscopic portals were made in the right paralumbar fossa and the right ovary was removed using the écraseur. Following removal of both ovaries a Caslick speculum was used to provide access to the colpotomy to facilitate closure. The colpotomy was sutured in a continuous pattern using laparoscopic needle holders or a pair of long needle holders.
beside the classic colpotomy what other techniques can you perform?
- laparotomy
- laparoscopic assisted colpotomy
- laparoscopy
- a two-step surgical procedure combining standing flank laparoscopy with recumbent ventral median celiotomy
Flank laparotomy has been recommended for ovaries that are less than
15cm
The most common complication that occurs at the flank surgery site is development of a
postoperative seroma or incisional infection.
A ventral approach to the abdomen can be via 3 sites, mention
midline,
paramedian
diagonal paramedian incision (preferred)
the diagonal paramedian laparotomy approach has as an advantage over the ventral midline and paramedian which is…
is positioned directly over the ovary, less tension is applied to the ovarian pedicle during vessel ligation than with the other ventral approaches.
The diagonal paramedian laparotomy approach is the most useful approach for the
majority of normal or enlarged ovaries
describ the incision the diagonal paramedian until the ovary is identified and pulled
GA - DR -
A 12- to 15-cm long incision is made starting approximately 5 cm cranial to the mammary gland and nearly bisecting the angle formed by the ventral midline and the inguinal depression. The incision is continued through the external rectus sheath, and the rectus abdominis muscle fibers are bluntly separated. Ligation and transection of one to two large neurovascular bundles found coursing perpendicular to the muscle fibers may be required. The internal rectus sheath is opened carefully with scissors. A hand is introduced into the peritoneal cavity, and the ovary is ID and pulled up to the incision. Stay sutures (USP size 2 polyglactin 910) are placed through the ovary in a cruciate pattern. Distended follicles are aspirated to reduce the size of the ovary and to facilitate passage of the enlarged ovary through the incision. Ligatures (USP size 1 or 2 absorbable suture) are placed around the cranial and caudal margins of the ovarian pedicle and used as additional stay sutures. A 90-mm thoracoabdominal stapling device (TA 90) is placed across the ovarian pedicle and discharged. The ovarian pedicle is transected between the stapler and the ovary. A vessel-sealing device can be used to provide hemostasis within the ovarian pedicle and then the pedicle is transected. The ovary is then removed from the surgery site (Fig 63-1)
Figure 63-1. Ovariectomy, using a commercial stapling unit (TA90) for hemostasis prior to ovary resection. No. 2 absorbable suture in an interrupted cruciate pattern. The external rectus fascia is closed with USP No. 2 absorbable suture in a continuous pattern, the subcutaneous tissue with USP No. 1 absorbable suture in a continuous pattern, and the skin with USP No. 0 absorbable suture in a continuous pattern.
The mares are hospitalized overnight and discharged when?
Most mares are hospitalized overnight and discharged the following day.
Posoperative care of laparaotomy for ovarium removal
Postoperatively, mares should be confined to a stall with hand grazing, and hand walking for 1 week, followed by 2 to 3 weeks of small paddock turnout prior to returning to routine care.
The 1ary advantages of the flank laparoscopy compared with the diagonal paramedian laparotomy for ovariectomy are
enhanced visualization of the surgical site with minimal tension on the ovarian pedicle, the ability to quickly and more confidently address potential hemorrhage, and avoidance of general anesthesia.
with surgical site drainage is more common in the diagonal paramedian laparotomy approach or flank laparoscopy?
flank approach
What is the material required for laparoscopy of the flank?
Videoendoscope camera, monitor,
Light source
Cable,
Insufflator and tubing (not always used), a 0-degree or 30-degree 30-cm or 57-cm rigid endoscope,
at least three 10-mm-diameter 15- to 20-cm-long cannulas with trocars,
Laparoscopic forceps, Scissors,
Injection needle, and Ligation instrumentation. Ligation of the ovarian pedicle can be done with ligating loop sutures, a stapling instrument, or a vessel-sealing device.
Placing local anesthetic into the mesovarium, rather than the ovary, has been shown to be more effective in reducing pain responses during surgery - TRUE OR FALSE
TRUE
what is the name of the forceps that provide a safe way to grasp the ovary?
Semm claw laparoscopic forceps
describe the laparoscopic portal
The exact sites of the incisions for the laparoscopic portals vary between surgeons. The hand-assisted laparoscopic ovariectomy technique commences with a modified grid flank approach to the abdomen.4 The cannulas for the endoscope and instruments then are placed to avoid trauma to bowel or the spleen. The ovary is visualized and the mesovarium is desensitized with lidocaine hydrochloride or mepivicaine hydrochloride. Placing local anesthetic into the mesovarium, rather than the ovary, has been shown to be more effective in reducing pain responses during surgery.25 The bipolar vessel-sealing device (LigaSure Atlas) (see Chapter 13) has been used effectively in the authors’ hospital, and others, for hemostasis and transection of the mesovarium (Figure 63-2).26 Semm claw laparoscopic forceps grab the ovary. one of the portals needs to be lengthened to remove an enlarged ovary or ovary is reduced in smaller pieces by direct sharp dissection using a morcellator while held against the body wall incision
Closure: appose muscles followed by subcut and fascia and finally skin
However, USP No. 2 polyglactin 910 sutures placed in a cruciate pattern through the ovary provide a more confident purchase of the ovary than the forceps during laparoscopy - TRUE or FALSE
TRUE
describe the 2 step surgical procedure combining standing laparo and recumbent ventral median celiotomy
Standing flank laparoscopy is used to transect the ovarian pedicle and mesovarium. The mare is then anesthetized and placed in dorsal recumbency. A ventral median celiotomy is used to remove the enlarged ovary from the abdominal cavity. This technique was utilized in 20 mares without any intraoperative or postoperative complications. Within this group of mares 15 of 20 had an ovary that was greater than 20 cm in diameter.
What technique allows the ovary to be reduced in size for removal?
Aspiration or morcellation.
Cannula insertion complications
1) include retroperitoneal insufflation,
2) splenic or bowel puncture,
3) hemorrhage from laceration of the circumflex iliac artery.
What is a reported advantage of transvaginal NOTES ovariectomy?
Provides excellent viewing of the caudal abdomen.
What is a uterine cyst, and where is it typically found?
Fluid-filled structures found in the uterus, often in older mares.
What is the preferred method for removing uterine cysts?
Laser ablation.
How are uterine cysts commonly diagnosed?
Through rectal examination or ultrasonography.
Why can uterine cysts affect fertility?
They can hinder pregnancy diagnosis and affect placentation.
Why is the cervix closed during cyst removal?
To maintain uterine insufflation.
What type of laser is used for uterine cyst ablation?
A diode laser.
What precaution is taken to avoid endometrial damage?
Avoid overinflating the uterus.
What is the benefit of using fluid distension during cyst removal?
It prevents smoke generation during laser ablation.
How is the uterus treated post-ablation?
Lavaged with sterile fluids and infused with antibiotics.
How long is postoperative anti-inflammatory treatment for cyst removal?
3 to 5 days.
What was the observed fertility rate in mares following cyst ablation?
73% for mares bred the year after ablation.
What factor increases the likelihood of foaling after ablation?
Mares younger than 17 years have higher fertility rates.
What recurrence prevention measure is taken for uterine cysts?
Ablating the cyst lining and base.
