Contrast-Enhanced Ultrasonography (CEUS) in Imaging of the Reproductive System in Dogs: A Literature Review

SIMPLE SUMMARY: Contrast-enhanced ultrasound (CEUS) has been widely applied for reproductive imaging in humans and animals. This structured literature review aims to analyze the usefulness of CEUS in canine reproduction. Articles from 1990 to 2022 about CEUS in canine testicles, prostate, uterus, placenta, and mammary glands were searched on PubMed and Scopus. Thirty-six total results were found. The analysis of these works enlightened the usefulness of CEUS in testicular abnormalities and neoplastic lesions, except for characterizing tumors. CEUS in dogs was studied in animal models for human prostatic cancer treatment, while in veterinary medicine it was used to study prostatic vascularization and to assess prostatic diseases, showing good specificity for adenocarcinomas. CEUS differentiated the follicular phases in ovaries. In CEH-pyometra syndrome, it differentiated endometrium and cysts, and highlighted angiogenesis. CEUS was shown to be safe in pregnant dogs and was able to assess normal and abnormal fetal–maternal blood flow and placental dysfunction. In normal mammary glands, CEUS showed vascularization only in diestrus, with differences between mammary glands. CEUS was not specific for neoplastic versus non-neoplastic masses and for benign tumors, except for complex carcinomas and neoplastic vascularization. Works on CEUS showed its usefulness in several pathologies as a non-invasive, reliable diagnostic tool. ABSTRACT: The use of contrast-enhanced ultrasound (CEUS) has been widely reported for reproductive imaging in humans and animals. This review aims to analyze the utility of CEUS in characterizing canine reproductive physiology and pathologies. In September 2022, a search for articles about CEUS in canine testicles, prostate, uterus, placenta, and mammary glands was conducted on PubMed and Scopus from 1990 to 2022, showing 36 total results. CEUS differentiated testicular abnormalities and neoplastic lesions, but it could not characterize tumors. In prostatic diseases, CEUS in dogs was widely studied in animal models for prostatic cancer treatment. In veterinary medicine, this diagnostic tool could distinguish prostatic adenocarcinomas. In ovaries, CEUS differentiated the follicular phases. In CEH-pyometra syndrome, it showed a different enhancement between endometrium and cysts, and highlighted angiogenesis. CEUS was shown to be safe in pregnant dogs and was able to assess normal and abnormal fetal–maternal blood flow and placental dysfunction. In normal mammary glands, CEUS showed vascularization only in diestrus, with differences between mammary glands. CEUS was not specific for neoplastic versus non-neoplastic masses and for benign tumors, except for complex carcinomas and neoplastic vascularization. Works on CEUS showed its usefulness in a wide spectrum of pathologies of this non-invasive, reliable diagnostic procedure.