Endoscopy Guided Photoablation of Endometrial Cysts using a 980 nm Laser with a Contact Fiber in Mares

Summary

The aim of this report is to describe the photoablation of endometrial cysts in the mare using an endoscopic laser device, and to discuss the interest and limitations of this new approach to deal with low fertility issues.

Abstract

In mares, endometrial cysts are associated with endometriosis and can cause maternal recognition failure or compromise and delay pregnancy diagnoses. Historical treatments were invasive and had adverse effects on the endometrium. Hysteroscopically guided laser therapy is easy and effective for endometrial cysts resection, with no deleterious effects for the endometrium.

A 110 cm long and 1.0 cm wide endoscope is sterilely introduced in the uterus through the open cervix of an estrous mare after vulvar cleaning. The uterus is slowly infused with less than 1 L of physiologic solution and the laser fiber is inserted in the biopsy canal of the endoscope. Cysts are then cauterized with the 980 nm diode laser with a contact fiber set at 20‒2 5W in continuous mode. Each cyst is punctured until complete voiding of the cyst and shrinking of the cyst wall around the fiber. Uterine lavages with sterile saline solution are performed directly after the surgery and for one or two days as non-inflammatory fluid can be observed.

This procedure is easy and quickly performed, with no obvious deleterious effects. Cysts resection makes ultrasound pregnancy diagnosis easier and, in some cases, could restore proper embryo migration in the uterine horns between day 6.5 and 17. However, this treatment does not improve the underlying histological lesions related to endometriosis. These considerations should be clearly expressed to the breeder before this procedure.

Introduction

Endometrial cysts in mares were histopathologically described in the seventies by Kenney¹. In the late eighties, the use of hysteroscopy and ultrasonography led to their clinical description and helped to understand their consequences on fertility^2,3,4,5.

In the early stages, endometrial cysts have been associated with a degeneration of the endometrium now called endometrosis^1,3,4,

Protocol

The presented protocol is used for mares presented in the equine hospital and follows institutional animal care guidelines.

NOTE: Perform endometrial cysts photoablation before anestrus: heats observed in late July or August thus seem most reliable. Do not perform this procedure too late in the breeding season as it can limit the number of estruses available to treat a potential endometritis.

1. During the preceding estrus

1. Perform a complete breeding soundness examination of the mare, including an endometrial biopsy¹ (not described here) to ensure that the mare can potentially ....

Results

Surgeries were performed on mares having cysts with diameters over 15 mm. However, if other smaller cysts were also present, photoablation of the other cysts was attempted. Generally, these large cysts were at the bifurcation or the basis of the horns. However, some of them were present in the body of the uterus and were equally treated. 

In our experience, intraluminal cysts are very easy to localize with the endoscope. Moreover, performing this procedure in saline solution increases the visi.......

Discussion

Hysteroscopy and laser photoablation of endometrial cysts is an easy procedure to reduce large intra-luminal cysts in the mare, as previously suggested¹⁴. Technically, this method is improved when performed on a mare in estrus. Inflating the uterus with sterile saline solution improved visibility when compared to air filling and continuous aspiration while performing the procedure.  Small intra-parietal cysts (<10 mm) are more difficult to reach and to treat. Moreover, treating these smal.......

Materials

List of materials used in this article

Name	Company	Catalog Number	Comments
Butorphanol	Animedica	Morphasol 10 mg/mL
Detomidine	Dechra	Domidine 10 mg/mL
Endoscope	Olympus	Vet 170-10 SN2012729
Endoscope Vidéo Tower	Olympus	CLE-E & CV-E
Laser device	Wuhan Giga Optronics	Velas II-60B GA19-V3186
NaCl 0.9%	Baxter
Pénicilline-procaïne	Kela	PENI-Kel 300.00 UI/ml
Ultrasonography	Aloka	Aloka 500 & 5mHz transrectal probe