Imaging of Canine Neoplastic Reproductive Disorders

Ultrasonographic computer-assisted quantification of the intraluminal uterine content in female dogs

In dogs, the characterization of intraluminal uterine contents has been subjectively carried out by the operators. The aims of this study were: 1) To ultrasonographically describe and compare the echogenicity and heterogeneity of the intraluminal uterine contents in bitches using digital analysis; 2) To assess the cytology of the uterine contents; 3) To evaluate the effect of clinical, ultrasonographic, bacteriological and cytological parameters on intraluminal contents echogenicity and heterogeneity. Twenty-one intact, 3-24 kg, 1-12 years of age, female dogs with ultrasonographically detected uterine content were included. According to the gross evaluation, the contents were classified as purulent (PC; n = 8), mucous (MC; n = 4), serous (SC; n = 9). Ultrasonographic images of the contents were digitally analyzed to measure echogenicity and heterogeneity, represented as the mean gray value (MGV) and the standard deviation of the gray value (SDG), respectively. Endometrial cytology samples were collected post-ovariohysterectomy. Clinical, ultrasonographic, bacteriological and cytological parameters were compared among groups using one way ANOVA and Chi-square tests. A generalized linear model was performed to analyze their effect on MGV and SDG. Uterine diagnoses included cystic endometrial hyperplasia - pyometra, cystic endometrial hyperplasia, cystic endometrial hyperplasia - mucometra, endometritis and normal uteruses. MGV was higher in PC and MC than in SC (P < 0.01), did not differ between PC and MC (P > 0.1). SDG was higher in PC than in SC (P < 0.01) and MC (P < 0.05). Digital analysis distinguished among purulent, mucous and serous fluids. Cytology revealed higher inflammation-related parameters in PC than in MC and SC. Cytological parameters, such as cellularity and bacterial presence, were associated with echogenicity and heterogeneity of uterine contents.

Morphophysiological Assessment of the Cervix during the Reproductive Cycle and Early Pregnancy in Does Using Computed Tomography and Oxytocin Receptor Immunohistochemistry

This study aimed to elucidate the morphophysiology and oxytocin receptor (OXTR) expression in the cervix of doe goats during various reproductive stages to enhance reproductive management strategies. A total of 40 cervical samples were categorized into follicular (n = 15), luteal (n = 10), and early pregnancy (n = 15) stages. Utilizing advanced imaging based on functional and morphological markers, the study employed computed tomography (CT) scans, histochemical staining (Masson trichrome and alcian blue), immunohistochemistry, Western blotting, and quantitative PCR (qPCR) to assess structural changes in the cervix and in OXTR expression during the estrous cycle and early pregnancy. CT scans revealed consistent cervical folds and a significant reduction in cervical width during pregnancy, suggesting structural adaptations for gestational integrity. Histochemical analyses indicated a well-organized collagen network and presence of mucins, essential for cervical function and integrity. Immunohistochemistry and Western blotting demonstrated elevated OXTR protein levels during the follicular stage, which were markedly reduced during pregnancy, indicating a role in facilitating cervical relaxation and sperm transport during estrus and maintaining cervical closure during gestation. qPCR analysis showed stable OXTR mRNA levels during follicular and luteal stages with a slight, non-significant increase during pregnancy, pointing towards posttranscriptional regulatory mechanisms. In conclusion, this study demonstrates that cervical morphology and OXTR expression in doe goats undergo significant changes across reproductive stages, with elevated OXTR protein levels during the follicular phase and notable reductions in cervical width and OXTR protein levels during pregnancy, indicating structural and functional adaptations for both reproductive processes and gestational integrity.

Contrast-Enhanced Ultrasound (CEUS) Evaluation of Canine Prostatic Hyperplasia before and after Osaterone Acetate Therapy: Preliminary Results

The prostate is the only sexual gland of the male dog, and dihydrotestosterone (DHT) regulates its growth. In intact dogs, constant DHT stimulation results in benign prostatic hyperplasia (BPH) that can be treated with osaterone acetate (OSA). This study describes the effects of OSA treatment, detected by contrast-enhanced ultrasonography (CEUS), highlighting prostatic vascularization with a contrast agent composed of gas microbubbles. Fifteen dogs (2-8 years) of different sizes and breeds (4-30 kg) diagnosed with BPH are involved in the study. Before treatment (D0), CPSE is measured (294.05 ± 115.97 ng/mL), and a B-mode ultrasound is performed (Vratio = 2.80 ± 1.85), confirming BPH. CEUS highlights the length of the wash-in (11.93 ± 2.08 s) and wash-out (42.20 ± 6.99 s) phases of the contrast agent in the prostate and the presence of cysts and parenchymal alteration. Dogs are treated with OSA (0.5 mg/kg for 7 days) and reassessed after 21 days (D1): CPSE and prostate volume are significantly (p < 0.001) reduced. The length of the wash-in (14.73 ± 2.54 s) and wash-out (51.13 ± 6.03 s) phases are significantly (p < 0.001) increased. The results confirm the effectiveness of the treatment, particularly the reduction in prostatic perfusion, confirmed by the increase in diffusion times of the contrast. Although preliminary, these findings are promising for the use of CEUS in monitoring dogs with BPH.

Diagnostic value of ultrasonography in identifying unilateral ovarian luteoma in a dog

Background

Diagnosing ovarian tumors in dogs can be challenging since the clinical symptoms are often generic. The present case report underscores a rare case in which a suspected unilateral ovarian tumor in a dog was initially identified using ultrasonography and subsequently confirmed to be a luteoma through postoperative histopathology.

Case Description

An 8-year and 6-month-old female Maltese dog presented with a 10-day history of vulvovaginal bleeding, hematuria, and decreased appetite. Physical examination revealed only vaginal bleeding, with no other abnormalities. Laboratory examinations showed no abnormalities, while abdominal radiography revealed the presence of cystic calculi as the sole abnormality. Abdominal ultrasound revealed an enlarged right ovary with regular contour and echogenicity, featuring unusual cystic components surrounding the right ovarian parenchyma. Furthermore, irregular thickening with multiple cystic lesions was observed in the endometrial wall of the bilateral uterine horns, indicative of cystic endometrial hyperplasia. Ultrasonographic findings suggested unilateral right ovarian disease. During ovariohysterectomy, the right ovary was slightly larger than the left ovary and adhered to the surrounding mesenteric fat layer and right pancreatic parenchyma. Histopathological examination confirmed the diagnosis of luteoma in the right ovary. Three days after surgery, the patient's clinical signs exhibited complete improvement, with the return of normal appetite.

Conclusion

This case report highlights a rare diagnosis of unilateral ovarian luteoma based on mild ultrasonographic abnormalities, which was ultimately confirmed on histopathological examination.

Ultrasound-Based Technologies for the Evaluation of Testicles in the Dog: Keystones and Breakthroughs

Ultrasonography is a valuable diagnostic tool extensively used in the andrology of human and domestic animals, including dogs. This review aims to provide an overview of various technologies based on ultrasound, from the basic B-Mode ultrasonography to the more recent advancements, such as contrast-enhanced ultrasonography (CEUS) and ultrasound elastography (UEl), all of which are utilized in the evaluation of canine testicles. The review outlines the principles behind each of these technologies and discusses their application in assessing normal and abnormal testicular conditions. B-mode canine testicular ultrasonography primarily focuses on detecting focal lesions but has limitations in terms of objectivity. Other technologies, including Doppler ultrasonography, B-Flow, and CEUS, allow for the characterization of vascular patterns, which could be further measured using specific applications like spectral Doppler or quantitative CEUS. Additionally, ultrasound elastography enables the assessment of parenchyma stiffness both qualitatively and quantitatively. These ultrasound-based technologies play a crucial role in andrology by providing valuable information for evaluating testicular function and integrity, aiding in the identification of pathological conditions that may impact the health and quality of life of male dogs.

Clinical and ultrasonographic findings of ovarian tumours in bitches: A retrospective study

A retrospective study was carried out to investigate incidence, clinical signs and ultrasonographic findings of ovarian tumours in a population of dogs referred to the Veterinary Teaching Hospital of the University of Perugia (Italy) and Anicura Tyrus Veterinary Clinic (Terni, Italy). The period of study ranged from January 2005 to December 2021. A total of 1910 dogs were affected by neoplasia but only 35 of them (1.8%), of different breeds and ages, were found to have ovarian tumours. Ultrasound of the ovaries was performed based on clinical signs; the diagnosis was achieved after ultrasound findings prompted ovariohysterectomy and ovarian pathologic evaluation In our study, the age of bitches affected by ovarian neoplasia ranged from 3 to 20 years (mean 9.6 ± 3.8). The histopathological findings of ovarian masses identified 16 granulosa cell tumours (GCT) (46%), 7 adenomas (20%), 5 adenocarcinomas (14%), 2 teratomas (6%), 1 leiomyoma (3%), 1 luteoma (3%), 1 tecoma (3%), 1 dysgerminoma (3%), and 1 haemangiosarcoma (3%). In particular, with respect to clinical signs, 69% of bitches showed abnormalities of estrus cycle (short interestral interval, persistent estrus, prolonged interestral interval). The other main clinical signs included abdominal distention, palpable abdominal mass, vulvovaginal discharge, polyuria/polydipsia, mammary masses. When present, the laboratory abnormalities were slight anemia and leucocytosis with neutrophilia. The tumours were ultrasonographically classified as mainly solid: 12/35 (34%) (1 adenoma, 4 adenocarcinomas, 1 dysgerminoma, 1 haemangiosarcoma, 1 leyomioma, 1 luteoma, 1 GCT, 1 tecoma, 1 teratoma); solid with cystic component 13/35 (37%) (9 GCT, 2 Adenomas, 1 adenocarcinoma, 1 teratoma); and mainly cystic 10/35 (29%) (6 GCTs, 4 adenomas). In our study, the ultrasound examination allowed us to suspect ovarian neoplasia in asymptomatic subjects referred for breeding management or for preventive health check. On the basis of our data, we proposed to perform a complete periodic examination of the reproductive system once a year from 6 years. Nevertheless, the presence of ovarian neoplasms found in young subjects, during breeding management, suggest including routine ultrasound examination of the reproductive tract.

[Diagnostic utility of the anti-Mullerian hormone in companion animals]

The anti-Mullerian hormone is a glycoprotein secreted by Sertoli cells in males and granulosa cells in females. The initial identification of this hormone in canine and feline serum was achieved in 2011. Meanwhile, a variety of studies have demonstrated its clinical significance as a tool in the endocrine diagnosis. This review summarizes the current knowledge about anti-Mullerian hormone in small animal reproduction and describes future opportunities for its diagnostic usage.

Imaging techniques in veterinary medicine. Part II: Computed tomography, magnetic resonance imaging, nuclear medicine

Radiography and ultrasonography are the most used techniques in veterinary clinical practice, due to organizational, managerial and, mostly, economic reasons. However, in the last decades, Computed tomography (CT), Magnetic Resonance Imaging (MRI) and, to a lesser extent, Nuclear Medicine (MN) are increasingly used. As we said in the previous article, all the Diagnostic Imaging techniques are actually "indispensable" in Veterinary Medicine, where many patients do not show any symptoms.This second part describes Computed Tomography (CT), Magnetic Resonance (MRI) and Nuclear Medicine techniques in Veterinary Medicine are described.

Computed tomography can differentiate vaginal-origin from uterine-origin lesions in bitches

OBJECTIVE

To investigate typical computed tomography (CT) features for the differentiation of vaginal from the uterine origin in dogs.

ANIMALS

7 healthy Beagles in the prospective study and 5 bitches in the retrospective study.

PROCEDURES

In the prospective study, dual-phase CT images were obtained from sexually intact female Beagles (n = 7) during anestrus and estrus. On the CT images, the vagina and uterine horns, body, and cervix were assessed for diameter, attenuation, and contrast enhancement pattern. In the retrospective study, CT features of large vaginal lesions (leiomyoma, leiomyosarcoma, adenocarcinoma, hematocolpos, and Gartner's duct cyst) were assessed in 5 bitches.

RESULTS

In normal bitches, the cervix was thicker with strong central enhancement compared to the uterus and vagina. The uterine artery, which enters the mesometrium at the level of the cervix, was clearly visualized and assisted in identifying the cervix. In bitches with large vaginal masses, uterine arteries were displaced by the lesions and could not be used to locate the cervix. In 4/5 dogs with vaginal masses, identification of the cervix allowed the determination of the organ of origin. In 1 dog with adenocarcinoma, CT vaginography was additionally required for determining the origin of mass.

CLINICAL RELEVANCE

Results from this study indicate that the cervix, recognized in CT as focal thickening of the uterus with central enhancement, may be used as a landmark for the differentiation between the uterus and vagina in bitches.

Computed tomography and magnetic resonance imaging findings in dogs with vaginal leiomyoma and leiomyosarcoma

BACKGROUND

In humans, magnetic resonance imaging (MRI) is preferred over computed tomography (CT) for the assessment of pelvic lesions. Although CT findings of several pelvic tumours have been reported in veterinary medicine, MRI findings are limited.

OBJECTIVES

The purpose of this study was to retrospectively compare the CT and MRI findings in dogs with vaginal leiomyoma and leiomyosarcoma.

METHODS

This retrospective study of five dogs compared the CT and MRI findings of intrapelvic lesions, including vaginal leiomyoma (n = 4) and leiomyosarcoma (n = 1). No invasion of the surrounding tissue was detected on histopathological examination. In this retrospective study, the following parameters of CT and MRI were recorded for each dog: the border between the lesion and the adjacent pelvic organs, including the prostate, rectum or urethra; signal intensity (SI) of the lesion; enhancement pattern; presence of haemorrhage; necrosis or cystic areas and lymphadenopathy. Because SI on MRI is affected by cell density, tumour cell density was analysed using a microscope slide.

RESULTS

In vaginal leiomyoma, the border between the lesion and the surrounding pelvic organ tends to be clearer on MRI than on CT. In vaginal leiomyosarcoma, the border was comparable between MRI and CT. Each lesion showed heterogeneous enhancement on CT and MRI scans. In each lesion, the assessment of haemorrhage, necrosis, cystic areas and lymphadenopathy was comparable between MRI and CT. The SI of the lesion on T2WI of the vaginal leiomyoma and leiomyosarcoma were hyperintense in four cases (4/4; 100%) and mixed intense in one case (1/1; 100%), respectively. The cell density of leiomyosarcoma is higher than that of leiomyomas.

CONCLUSIONS

The SI on T2WI may be useful for differentiating leiomyoma from leiomyosarcoma. MRI may be useful to differentiate vaginal leiomyomas from leiomyosarcomas and evaluate margins.