Case Study

Cystic ovarian remnants in a 10 month old FS Labrador Retriever dog

A 10-month-old spayed female Labrador was presented for evaluation of showing signs of estrus.

Sonographic Differential Diagnosis

Cystic structures noted at the caudal pole of both kidneys, which is consistent with cystic ovarian tissue. However, cystic lymph nodes or peri-renal fat could be considered differentials.
It is recommended to submit hormone blood testing to further confirm potential for ovarian tissue that is actively producing hormones in this patient. Exploratory laparotomy would be required in order to make final determination of the presence of cystic ovarian tissue with the purpose of removing any such tissue that is potentially present.

Image Interpretation

There was no evidence of uterine tissue or potential for stump pyometra. An anechoic, small, cystic structure measured 0.8 cm in size was visualized approximately 1.0 cm caudal to the caudal pole of the left kidney. The cystic structure did not show any evidence of Doppler signal when color flow was applied. This could be consistent with an ovarian cyst. However, other structures such as lymph nodes can also appear cystic and cannot be rule out. The caudal pole of the right kidney was specifically identified and a structure with multiple, small, anechoic cysts was identified. This measured 1.1 cm in width and was located 1.0 cm caudal to the caudal pole of the right kidney. Again there was no evidence of blood flow present within this cystic structure.

DX

Cystic ovarian remnant

Outcome

Luteinizing hormone was negative; therefore, the cystic structures were indicative of ovarian remnants. It is recommended to pursue exploratory surgery when the patient goes into heat again.