Ovarian remnant syndrome in the bitch: a literature review

Abstract

RESUMENEl síndrome de ovario remanente es una complicación conocida y de larga duración de la ovariectomía u ovariohisterectomía, que es causada por la presencia de tejido ovárico activo a pesar de una cirugía electiva. Como resultado de dejar restos de tejido ovárico en el abdomen o debido a la presencia de tejido ovárico ectópico, se desarrollan signos clínicos típicos de proestro o estro tales como hinchazón de la vulva, sangramiento o cambios conductuales. El diagnóstico se realiza por citología vaginal, medición de hormonas gonadales, ultrasonografía y cirugía exploratoria. La excisión quirúrgica de la masa ovárica es el tratamiento recomendado, lo cual es un proceso difícil. Este trabajo describe las causas del síndrome, los signos clínicos del paciente, el diagnóstico y el tratamiento del síndrome de ovario remanente en perras.Palabras clave: perro, ovariohisterectomía, estro postoperación, sangramiento vaginal

Clinical case of ovarian remnant syndrome in a cat

“…Three explanations have been suggested for the development of ORS in companion animals (Feldman and Nelson 2004;Sontas et al, 2007). The first and the most accepted explanation is incomplete surgical removal of one or both ovaries as a surgical error.…”

“…During the surgery, the caudal poles of both kidneys, the broad ligament, the omentum and the abdominal wall should be examined deeply to identify any ovarian tissue. Moreover, the ligature site at the uterine-cervical junction and proper ovary ligament should be inspected to identify any pathological condition of the uterus as uterine horn or uterine body may be remnant as well (Manfra-Marretta et al, 1989; Sontas et al, 2007). It was demonstrated by Miller, 1995, that in most cases ovarian remnants were located around the ovarian pedicles.…”

“…Because ovaries are the sole source of AMH, a positive test would indicate the presence of ovaries or ovarian tissue (Place et al, 2011, Yilmaz et al, 2015. Differential diagnosis for ORS are the conditions that cause bloody vulvar discharge including vaginal neoplasia, vaginitis, uterine stump pyometra, trauma, exogenous estrogen therapy and coagulopathy (Sontas et al, 2007). One differential diagnosis for a false-positive identification of residual ovarian tissue during ultrasonography is a suture granuloma at the site of ligation of the ovarian pedicle.…”

“…The first and the most accepted explanation is incomplete surgical removal of one or both ovaries as a surgical error. This may be due to a small abdominal wall incision that makes difficult to visualize, reach and carry out the ligature of the ovary or ovaries, or to incorrect ligaturing of ovarian tissues or anatomical location of the right ovary (Wallace, 1991, Miller, 1995, Johnston et al, 2001a, Prats, 2001, Sontas et al, 2007. Anatomically, the right ovary and uterine horn are located in a more cranial position than the left ovary and uterine horn and the I S S U E 2 , 2 0 1 7 suspensory ligament is shorter, making that ovary more difficult to exteriorize, which predisposes the surgeon to leave the ovary during the surgery (Evans andChristensen, 1993, Sontas et al, 2007 In the above and in another clinical report (Pearson, 1973;Okkens et al, 1981;Musal and Tuna, 2005) it was observed that in 58% and 71% of uterine stump pyometra cases there is also functional ovarian tissue present.…”

“…Diagnostic imaging may be used to find residual ovarian tissue, but both ultrasound and CT may miss residual tissue if it is very small, if the patient is in anestrus. So ORS cannot be ruled out if abnormal tissue is not seen (Ball et al, 2007;Sontas et al, 2007). There are several tests to diagnose ovarian remnants in a patient with clinical signs.…”