Use of New Ultrasonography Methods for Detecting Neoplasms in Dogs and Cats: A Review.

The aim of this literature review was to present the novel imaging modalities elastography and contrast-enhanced ultrasonography. We provided an overview of the concepts and applications of each technique for the investigation of neoplastic and metastatic tumors in dogs and cats. Studies on elastography are based on the elasticity and deformation of the evaluated tissue. The information obtained from the different types of elastography can aid in the detection and differentiation of malignant and benign structures. Descriptions of elastography studies in several organs and tissue in veterinary medicine reported that, in general, malignant tumors tend to be more rigid and, therefore, less deformable than benign lesions or in comparison to the healthy parenchyma. Contrast-enhanced ultrasonography is based on the intravenous injection of contrast media constituted by microbubbles. This imaging modality can be performed in nonsedated animals and provides information on the tissue perfusion, allowing the investigation of macro- and micro-circulation. Studies on different organs and tissues were performed in dogs and cats and revealed a tendency of malignant tumors to present faster transit of the contrast media (time to wash-in, peak and wash-out). These advanced techniques can be associated with other imaging modalities, aiding important information to the well-established exams of B-mode and Doppler ultrasonography. They can be used as screening tests, potentially representing an alternative to the invasive sampling methods required for cytological and histopathological analysis.

The Importance of Ultrasonography in the Evaluation of Mammary Tumors in Bitches.

The high incidence of mammary tumors in small animals is concerning. Patient history, clinical examination, physical evaluation, and imaging studies are important for clinical staging. Ultrasonography is commonly applied to investigate the presence of abdominal metastasis. However, it has been shown to provide important information regarding mammary tumors' architecture and advanced sonographic techniques can provide information regarding neovascularization, stiffness, and perfusion. Different techniques have been investigated to determine accuracy to predict the lesions' histological classification. This paper reviews the information regarding each sonographic technique in the evaluation of mammary tumors, describing the most common findings and their potential to accurately assess and predict malignancy. Even though the gold standard for the diagnosis of mammary lesions is the histopathological examination, some ultrasonographic features described can predict the potential of a lesion being malignant. Among the different sonographic techniques, elastography can be considered the most reliable modality to accurately differentiate benign from malignant tumors when malignant lesions present increased stiffness. However, the combination of all sonographic techniques can provide important information that can lead to a better therapeutic approach and clinical staging. Furthermore, the potential of the sonographic study, especially CEUS to monitor therapeutic progression, demonstrate the need of further studies.

Abdominal perfusion in canine patients with pyometra and sepsis evaluated by Doppler and contrast-enhanced ultrasound.

BACKGROUND: Sepsis is a condition characterized by organic dysfunction, leading to hemodynamic instability and high morbidity and mortality rates in humans and animals. Early identification of perfusion changes and appropriate management of sepsis are crucial for improving patient prognosis. Currently, the Systemic Inflammatory Response Syndrome (SIRS) and Sequential Organ Failure Assessment (SOFA) scores are widely studied for sepsis identification and evaluation of organ dysfunction. However, these scores do not assess gastrointestinal involvement, which is common in this condition. Contrast-enhanced ultrasound (CEUS) and Doppler have been considered promising diagnostic techniques for detecting changes in vascularization and microcirculation in a non-invasive and safe manner, particularly in the gastrointestinal system. This study aimed to evaluate duodenal perfusion using CEUS, as well as abdominal aortic and cranial mesenteric artery blood flow using Doppler ultrasound, and systolic arterial pressure (SAP) in 17 bitches with pyometra and in 10 healthy animals. RESULTS: The variables were compared between the pyometra and control groups, as well between patients with and without sepsis determined by the SOFA or SIRS scores. Pyometra was found to cause a reduction in abdominal aortic blood flow volume, aortic peak systolic velocity, and resistivity index as evaluated by Doppler ultrasound. Patients with sepsis according to the SOFA criteria only presented lower SAP. In contrast, sepsis animals identified by the SIRS score exhibited lower SAP, aortic peak systolic velocity, aortic blood flow volume, and aortic resistivity index and additionally, higher peak intensity of contrast in the duodenal wall. CONCLUSIONS: Pyometra causes a reduction in abdominal aortic blood flow, which is more pronounced in animals with sepsis identified by the SIRS criteria. These animals also exhibited a decrease in systolic blood pressure and an increase in duodenal perfusion, as evident by CEUS. However, these changes were not observed in patients with sepsis identified by the SOFA criteria. The alterations in intestinal perfusion observed in animals with sepsis indicate the presence of inflammation or dysfunction. In this regard, CEUS proves to be a valuable technique for detecting subtle changes in tissue hemodynamics that may not be apparent in conventional exams.

Characterization of uterine involution using B-mode ultrasonography, color Doppler and elastography (acoustic radiation force impulse) for assessing postpartum in Santa Inês ewes.

The aim of this study was to investigate uterine involution using ultrasonography techniques during postpartum. Postpartum ultrasonography evaluation (B-mode, color Doppler and Acoustic Radiation Force Impulse elastography) of the uterus was performed by transabdominal approach at immediate after birth and sequentially every 48 hours, during 30 days. The uterine echotexture did not present significant variations (P >0.05) being homogeneous in most evaluations; echogenicity of the uterus increased along the evaluation period (P =0.0452). Progressive and remarkable decrease of the total uterine diameter (UD) were observed (P <0.0001), especially during the first days postpartum. The thickness of uterine wall gradually decreased, as well the endometrial, myometrium and lumen diameters (P <0.0001). Uterine blood flow was assessed by Doppler and decreased during postpartum period, being significantly lower (P=0.0225) on the 30th day of postpartum. Uterine parenchyma presented as homogeneous dark areas (not deformable) on qualitative ultrasound elastography and the means shear velocity values of the uterine wall on quantitative elastography did not differ. This is the first study that evaluate the stiffness of uterine wall in healthy ewes, providing baseline data about quantitative and qualitative stiffness of the normal uterus, and it may be a useful tool for early diagnosis of uterine alterations during the postpartum period, using the reference parameter established for the assessment of uterine integrity during postpartum period.

Maternal and fetal ultrasonography, vulvar temperature and vaginal mucous impedance for the prediction of parturition in Saanen does.

The aim of this study was to evaluate and correlate modifications of vaginal mucous impedance, vulvar temperature and ultrasonographic measurements (echobiometric parameters) to parturition in pregnant Saanen does. 30 does were selected for the study and submitted to an estrus synchronization protocol and natural mating. The females were evaluated daily from Day 143 of pregnancy to parturition. For the sonographic evaluations, the following structures were measured: biparietal diameter, thoracic diameter, abdominal diameter, ocular orbit, kidney length, kidney height, cardiac area, placentome length, cervical measurement and fetal heart rate; by means of two different approaches: transrectal and transabdominal, using a 7.5 MHz linear transducer. The vaginal mucous impedance was assessed using an electric estrous detector and vulvar temperature was measured using a non-contact infrared thermometer. Statistical analysis was performed using the R-project software and the significance level was set at 5% for all tests. 25 Saanen does became pregnant, resulting in 80.33% pregnancy rate. Fetal heart rate was negatively correlated to the hours to parturition (p<0,001; r-Pearson= -0,451), as well as vaginal temperature (p= 0,001; r-Pearson= -0,275), while cervical thickness was positively correlated to hours to parturition (p<0,001; r-Pearson= 0,490). The echobiometric parameters (biparietal diameter, thoracic diameter, abdominal diameter, ocular orbit, kidney length and height, cardiac area, placentome length), as well as vaginal mucous impedance did not vary throughout the timepoints of evaluation and did not correlate to the moment of parturition. It was concluded that the parameters of fetal heartbeat, vaginal temperature and cervical effacement in the last week of pregnancy provide valuable information regarding the proximity of parturition.

Diagnosis, Prognosis, and Treatment of Canine Hemangiosarcoma: A Review Based on a Consensus Organized by the Brazilian Association of Veterinary Oncology, ABROVET.

Hemangiosarcoma is a mesenchymal neoplasm originating in the endothelial cells of blood vessels; they can be classified as non-visceral and visceral types. Non-visceral hemangiosarcomas can affect the skin, subcutaneous tissues, and muscle tissues; visceral hemangiosarcomas can affect the spleen, liver, heart, lungs, kidneys, oral cavity, bones, bladder, uterus, tongue, and retroperitoneum. Among domestic species, dogs are most affected by cutaneous HSA. Cutaneous HSA represents approximately 14% of all HSA diagnosed in this species and less than 5% of dermal tumors, according to North American studies. However, Brazilian epidemiological data demonstrate a higher prevalence, which may represent 27 to 80% of all canine HSAs and 13.9% of all skin neoplasms diagnosed in this species. Cutaneous HSA most commonly affects middle-aged to elderly dogs (between 8 and 15 years old), with no gender predisposition for either the actinic or non-actinic forms. The higher prevalence of cutaneous HSA in some canine breeds is related to lower protection from solar radiation, as low skin pigmentation and hair coverage lead to greater sun exposure. Actinic changes, such as solar dermatosis, are frequent in these patients, confirming the influence of solar radiation on the development of this neoplasm. There are multiple clinical manifestations of hemangiosarcoma in canines. The diagnostic approach and staging classification of cutaneous HSAs are similar between the different subtypes. The definitive diagnosis is obtained through histopathological analysis of incisional or excisional biopsies. Cytology can be used as a presurgical screening test; however, it has little diagnostic utility in cases of HSA because there is a high risk of blood contamination and sample hemodilution. Surgery is generally the treatment of choice for dogs with localized non-visceral HSA without evidence of metastatic disease. Recently, electrochemotherapy (ECT) has emerged as an alternative therapy for the local ablative treatment of different neoplastic types; the use of radiotherapy for the treatment of dogs with cutaneous HSA is uncommon. There is greater consensus in the literature regarding the indications for adjuvant chemotherapy in subcutaneous and muscular HSA; doxorubicin is the most frequently used antineoplastic agent for subcutaneous and muscular subtypes and can be administered alone or in combination with other drugs. Other therapies include antiangiogenic therapy, photodynamic therapy, the association of chemotherapy with the metronomic dose, targeted therapies, and natural products. The benefits of these therapies are presented and discussed. In general, the prognosis of splenic and cardiac HSA is unfavorable. As a challenging neoplasm, studies of new protocols and treatment modalities are necessary to control this aggressive disease.

Hemorrhagic prostatic cyst in a dog - case report.

We present the case of a five-year-old intact mixed breed male dog with hemorrhagic prostatic cysts. The patient presented with hematuria, dysesthesia, and pain on abdominal palpation. Abdominal ultrasound, hematology, urinalysis, and biochemical evaluation tests were subsequently conducted. Laboratory tests revealed cloudy urine with bacteria, and countless red blood cells. On ultrasound examination, the prostate was severely enlarged, with heterogeneous and reduced parenchyma, surrounding a large cavity filled with anechoic material with moderate cellularity. The urinary bladder was markedly distended and had a round, hypoechogenic structure in the lumen. The patient was hospitalized and had significant, irreversible worsening of the clinical symptoms and died. Subsequently, necropsy of the patient was performed and a histopathological diagnosis of benign prostatic hyperplasia associated with the presence of a prostatic hemorrhagic cyst, prostatitis, and chronic cystitis with an intraluminal blood clot was made. To the best of our knowledge, this is the first report to describe the occurrence of a hemorrhagic cyst in a canine prostate, thus bringing important information from clinical and imaging findings to the veterinary routine.

Apresentamos o caso de um cão macho de cinco anos de idade sem raça definida com cisto prostático hemorrágico. O paciente manifestava hematúria, disquesia e dor à palpação abdominal. Foram realizadas ultrassonografias abdominais subsequentes, hematologia, urinálise e testes de avaliação bioquímica. Os testes laboratoriais revelaram urina turva com bactérias e inúmeros glóbulos vermelhos. No exame ultrassonográfico, a próstata estava severamente aumentada, com parênquima heterogêneo e reduzido, circundando uma grande cavidade cheia de material anecoico com celularidade moderada. A bexiga urinária estava marcadamente distendida e tinha uma estrutura redonda e hipoecogênica no lúmen. O paciente foi internado e teve um agravamento significativo e irreversível dos sintomas clínicos e veio a óbito. Subsequentemente, foi realizada a necropsia do paciente e foi feito o diagnóstico histopatológico de hiperplasia prostática benigna associada à presença de um cisto hemorrágico prostático, prostatite e cistite crônica com um coágulo sanguíneo intraluminal. Tanto quanto sabemos, este é o primeiro relatório descrevendo a ocorrência de um cisto hemorrágico numa próstata canina, trazendo assim informações importantes dos resultados clínicos e de imagem para a rotina veterinária.

Ultrasonography and elastography of the brain and cerebellum of English Bulldog fetuses.

The aim of this study was to evaluate B-mode ultrasonography and ARFI elastography of the central nervous system of canine fetuses as complementary methods to predict gestational age, monitor fetal development and establish standards. Ultrasound examinations were performed on 26 English Bulldog bitches at 34, 49 and 60 days of gestation. The circumference (C), area (A) and diameters of the short (D1) and long (D2) axis of the two cerebral hemispheres of the fetuses in cross-section were measured. Fetal cerebellum shape, echotexture, echogenicity, and transverse diameter (TCD) were evaluated in cross-section. Elastography was performed obtaining color elastograms and mean shear wave velocity (SWV m/s) of the fetal brain and cerebellar tissues. Ultrasound variables were correlated with gestational day (GD). Brain masses had a circular to oval shape, hyperechoic echogenicity, and homogeneous echotexture. C and D1 were the more accurate variables to predict gestational day, with the formulas: GD = 19.38 + 2,06∗C (R2 = 81%) and GD = 18.93 + 7.45∗D1 (R2 = 82%). Cerebellum had a "banana" shape, with hyperechogenic edges, hypoechoic echogenicity, and homogeneous echotexture. The TCD (P = 0.0001) and cerebellar stiffness (P = 0.0006) were greater at 60 days than at 49 days of gestation. The brain mass SWV was correlated positively with GD (P = 0.0001) and showed a gradual increase (P = 0.0001) in the three gestational timepoints evaluated. According to qualitative elastography, both brain mass and cerebellum became more rigid over the course of gestational days. It was possible to verify the development of the brain and cerebellum of canine fetuses during pregnancy by ultrasonographic characteristics and B-mode dimensions, as well as by evaluating the elasticity of these tissues through elastography. These unpublished findings allow a better follow-up of the central nervous system development in the prenatal period and may help in future studies with canine fetuses that present cerebral and cerebellar abnormalities.

Doppler sonography of the umbilical and uterine arteries blood flow of pregnant Saanen goats.

The objective was to evaluate the blood flow of the uterine artery (UA) and umbilical artery (UMB) in the physiological pregnancy of goats by means of Doppler throughout the gestational period. Twenty-five Saanen goats weighing 55 ± 10 kg and aged between 2 and 5 were evaluated weekly, from the 21st until the 143rd day of gestation, and daily from that period until parturition. Values for peak systolic velocity (PSV), end diastolic velocity (EDV) and resistance (RI) and pulsatility (PI) indices of the uterine and umbilical arteries were determined. The values obtained were correlated with gestational age by Spearman's test, tested for adjustment to regression models and compared with the number of fetuses by ANOVA. The umbilical cord was first visualized at 28 days. Of the variables evaluated, RIUMB and PIUMB correlated with gestational age (p<0.001; and 0.046; respectively) and RIUMB had a low negative correlation with the number of fetuses per pregnancy (p = 0.003; r- Spearman = - 0.218). PSVUMB and EDVUMB values did not correlate with gestational age (p=0.737 and 0.768, respectively), but there was a decrease in the mean values throughout pregnancy (PSVUMB= 0.07; 0.31 and EDVUMB= 0.01; 0.06) as well as the change in the flow pattern of the spectral trace. The mean values of the uterine artery dopplervelocimetric variables PSVUT, EDVUT, PIUT and RIUT did not correlate with gestational age (p= 0.324; 0.372, 0.143; 0.13; respectively). It is expected that the results obtained will contribute to a broader understanding of the hemodynamic changes resulting from pregnancy in goats.

Applicability of ARFI elastography in detecting elasticity changes of the equine superficial digital flexor tendon with induced injury.

The objectives of this prospective, experimental study were to describe changes in the stiffness of the equine superficial digital flexor tendon (SDFT) after induced injury, deep digital flexor tendon (DDFT), accessory ligament (AL-DDFT), and suspensory ligament (SL) during 90 days of healing using acoustic radiation force impulse (ARFI) elastography. Eight healthy horses were selected. Preinjury B mode and ARFI evaluations were performed bilaterally in the palmar metacarpal region. Injury was induced only on the left forelimb (G2) by a single injection of collagenase in SDFT, 15 cm distal to the accessory carpal bone. The right forelimb was used as a control (G1). Evaluations were performed at eight timepoints: one before injury (T0) and seven (T1-T7) after injury (3, 15, 30, 40, 60, 75, and 90 days post-induction). Tendinopathies were visualized as hypoechoic areas with loss of parallel tendon fiber pattern. Injured SDFTs presented mainly cool colors (soft) from T1 to T3, and from T4, there was an increase in warm colors (hard), close to the appearance of tendons of G1. In the first four timepoints, there was a decrease in stiffness compared to G1 (P < 0.001). On T1 and T2, a cutoff value <6.21 m/s to determine tendinopathy of the SDFT was established (75.8% sensitivity and 92.03% specificity). Stiffness changes in the DDFT, AL-DDFT, and SL of injured limbs occurred at different timepoints. Tendinopathy significantly altered the stiffness of the injured tendon and the adjacent tissues. ARFI made it possible to detect these changes, helping to monitor the reparation of this injury.

Radiographic study of the axial and appendicular skeleton of Callithrix jacchus and Callithrix penicillata.

BACKGROUND: Marmosets are small arboreal primates. Knowledge of normal radiographic parameters and frequent disorders is limited. The objectives of this study were to evaluate possible variations between quantitative analyses and injuries to the appendicular and axial skeleton of Callithrix jacchus and Callithrix penicillata and their relationship with the environment. METHODS: Radiographic images of 29 marmosets were used. Skeletal lesions were described, long bones were measured, and pelvimetry, vertebrae, and sternebras were counted. RESULTS: Measurements of long bones and pelvimetry were similar between species. Evaluation of vertebrae and sternebras exhibited variations relative to the literature. Lesions on the skull, spine, thoracic and pelvic limbs were present in 48%, 54%, 44%, and 52% of marmosets, respectively. CONCLUSION: Skeletal disorders, especially of traumatic and metabolic origin, have a high prevalence in marmosets.

Accuracy of B-mode ultrasound and ARFI elastography in predicting malignancy of canine splenic lesions.

The objective was to evaluate the accuracy of B-mode ultrasonography and ARFI elastography in detecting malignancy in canine splenic lesions. Thirty-seven spleens with abnormalities (16 benign and 21 malignant) from dogs of different breeds and ages were evaluated. Echogenicity, echotexture, organ length and height were evaluated using B-mode. By ARFI elastography, tissue stiffness was evaluated qualitatively (elastogram) and quantitatively (measuring the shear wave velocity-SWV). Lesions were classified as diffuse, focal or multifocal (cranial, medial or caudal portion) and comparisons of the SWV between the injured and non-injured areas were performed. In the B-mode, no features were associated to malignancy (P > 0.05). In the elastogram, 35 spleens were non-deformable and 2 deformable, having no association with malignancy. The greater SWV was observed in malignant lesions (3.4 ± 0.6 m/s), followed by areas free from alterations (2.1 ± 0.3 m/s) and benign lesions (1.7 ± 0.5 m/s), with difference between groups (P < 0.0001). It was found that a SWV > 2.6 m/s indicates malignancy of canine splenic lesions (sensitivity of 95%, specificity of 100%, PPV of 100%, NPV of 94% and accuracy of 97%), concluding that ARFI elastography is a promising technique for differentiating malignancy in these lesions.

Malignancy prediction of cutaneous and subcutaneous neoplasms in canines using B-mode ultrasonography, Doppler, and ARFI elastography.

BACKGROUND: Cutaneous and subcutaneous neoplasms are highly prevalent in dogs, ranging from benign to highly aggressive and metastatic lesions. The diagnosis is obtained through histopathology, however it is an invasive technique that may take a long time to obtain the result, delaying the beginning of the adequate treatment. Thus, there is a need for non-invasive tests that can help in the early diagnosis of this type of cancer. The aim of this study was to verify the accuracy of B-mode ultrasonography, Doppler, and ARFI elastography to predict malignancy in cutaneous and subcutaneous canine neoplasms. In addition, we aim to propose an ultrasonography evaluation protocol and perform the neoplasms characterization using these three proposed techniques. RESULTS: Twenty-one types of specific neoplasm were diagnosed, and using B-mode, we verified the association between heterogeneous echotexture, invasiveness, presence of hyperechoic spots, and cavity areas with malignancy. An increased pulsatility was verified in malignant neoplasms using Doppler (cut-off value > 0.93). When using the elastography, malignancy was associated with non-deformable tissues and shear wave velocity > 3.52 m/s. Evaluation protocols were proposed associating 4, 5, 6, or 7 malignancy predictive characteristics, and characterization was done for all tumors with at least two cases. CONCLUSIONS: We concluded that ultrasonography methods are promising and effective in predicting malignancy in these types of tumors, and the association of methods can increase the specificity of the results.

Seminal characterization of white-lipped peccary (Tayassu peccary).

White-lipped peccary (Tayassu pecari) is a neotropical mammal that plays a fundamental role in maintaining the integrity of tropical forest systems. However, due to hunting and deforestation the species is currently classified as vulnerable. As there are reports of difficulties in captive reproduction, it was proposed to use assisted reproduction techniques for later reintroduction into their natural habitat. Therefore, the objective was to describe the physical, chemical, morphological and functional characteristics of its semen. Sixteen adult male, white-lipped peccary, aged between three and seven years old, distributed in three groups, were used in this study. After physical and chemical retainment, semen was collected by electroejaculation from 16 individuals. It was evaluated by computer analysis (CASA). The mean values recorded were as follows: volume 0.5 ± 0.6 ml, pH 7.2 ± 0.3, sperm concentration 967.2 ± 947.3 × 106 spermatozoon/ml and total motility of 75.4 ± 16.2. The average sperm reactive to the hypo-osmotic test was 85.3% ± 21.0%, and 62.4% ± 43.9% of the cells presented intact membranes in the structural integrity test. Additionally, the semen showed milky consistency (80%), yellowish colour (40%) and sui generis odour (100%). The sperm parameters of the white-lipped peccary are within the desirable standards, allowing them to be considered as potentially fertile for the development of assisted reproduction techniques that may contribute to the conservation of the species.

Ultrasonography of the nuchal translucency of healthy and abnormal English Bulldog fetuses.

The aim of this study was to measure the nuchal translucency (NT) of canine fetuses to establish reference values ​​for healthy gestational processes and to verify its effectiveness in the diagnosis of congenital abnormalities. On day 34 of gestation, the NT of three fetuses from each of the 26 English bulldog female dogs was measured. The first fetus was the one located immediately cranial to the bladder, the second was selected from the left side of the abdomen, and the third from the right side. The reference values for healthy animals were offset using descriptive statistics. The diagnostic ability of the test to identify fetal malformations was studied using receiver operating characteristic curve analysis. Of the 26 litters, only 18 had healthy fetuses, 4 had fetuses with anasarca, 3 had fetuses with abdominal wall defects, and 1 had both types of abnormalities. The NT was higher in canine fetuses that presented anasarca in the litter than in normal litters (1.8 ± 0.77 mm vs. 1.4 ± 0.48 mm; P = 0.0249), with a cut-off value of NT > 1.45 mm (sensitivity = 61.54%, specificity = 70.18%). NT greater than 1.45 mm seems to be a diagnostic tool for the identification of anasarca during gestation of bulldogs. Considering the unprecedented use of this parameter in canine species and the limitations found during the study, further studies will be needed in order to use it on clinical practice.

High-definition ultrasonography in the evaluation of the reproductive tract of bitches during the follicular phase of the estrous cycle.

The aim was to sonographically evaluate the reproductive tract of bitches during the follicular phase of the estrous cycle using High Density (HD) ultrasonic techniques. Females (n = 8) were evaluated at five different times throughout the follicular phase, as determined by vaginal cytology and blood progesterone concentrations. Ultrasonic exams were performed using the ACUSON S2000/SIEMENS device utilizing a multifrequency HD transducer (5.5-18 MHz). Videos of the ovaries were obtained and recordings were evaluated using a DICOM viewer software for counting and measuring the ovarian structures, which were assigned to groups based on diameter in mm: G1: ≤ 1; G2: from 1.01 to 3.5; G3 from 3.51 to 5.5; G4: from 5.51 to 10. There was a greater uterine thickness with the progression of the follicular phase (P < 0.05). Six distinct regions were identified in the uterine wall. The ovarian dimensions increased (P < 0.05) as stage of the follicular phase advanced. There was fluid detected around the ovaries after ovulation. There was a characteristic fat tissue hyperechogenicity around the ovaries at all timepoints. There was a difference in the number of ovarian structures of each dimension group at each time there were assessments (P < 0.05). There was a difference in diameter of the largest ovarian structure and in average value of wall thickness at all timepoints when there were evaluations (P < 0.05). The HD ultrasonography technique provides for excellent image resolution, allowing for a more precise characterization of the bitch's reproductive structures and changes occurring during the follicular phase of the estrous cycle.

Assessment of dopperfluxometric indices of maternal-fetal structures in pregnant ewes.

The aim of this study was to evaluate the blood flow of the uterine artery, fetal aorta and umbilical artery in the physiological pregnancy of sheep by means of pulsed Doppler throughout the gestational period. Thirty Santa Inês ewes weighing between 45.4±4.3 kg and aged 2 to 5 years were selected. The evaluations were carried out weekly from the 3rd to the 21st gestational week. Peak systolic velocity (PSV), end diastolic velocity (EDV) and resistance index (RI) were obtained. Analysis of variance was performed, and the minimum significant comparison of means was obtained by the BH test with adjusted P<0.05. The results were expressed as mean ± standard error. For the fetal aorta, there was an increase in the EDV values and a decrease in the PSV and RI throughout pregnancy. For the uterine artery, PSV and EDV did not present significant variation, whereas the RI showed a reduction in the last week. Increased EDV values were found for the umbilical artery throughout pregnancy. For the PSV there was no significant difference, as the RI was reduced at the end of pregnancy. The results obtained are expected to contribute to a more complete understanding of the hemodynamic changes resulting from pregnancy.

Liver and spleen elastography of dogs affected by brachycephalic obstructive airway syndrome and its correlation with clinical biomarkers.

The purpose of this study is to determine whether the brachycephalic obstructive airway syndrome (BOAS) is correlated to alterations in liver and spleen elasticity. Forty-eight brachycephalic and 22 mesocephalic dogs were submitted to a BOAS functional assessment, laboratory tests, abdominal ultrasound and liver and spleen Acoustic Radiation Force Impulse (ARFI) elastography. Dogs clinically affected by BOAS had higher values of liver stiffness (p < 0.001) than healthy dogs: medial lobes (1.57 ± 0.37 m/s), left and right lateral lobes (1.54 ± 0.50 m/s, 1.23 ± 0.28 m/s, respectively) and caudate lobe (1.28 ± 0.42 m/s). Compared to the mesocephalic group, the brachycephalic group (BOAS clinically affected and unaffected dogs) had higher spleen (2.51 ± 0.45 m/s; p < 0.001) and liver stiffness (p < 0.001): medial lobes (1.53 ± 0.37 m/s), left and right lateral lobes (1.47 ± 0.47 m/s, 1.20 ± 0.30 m/s, respectively) and caudate lobe (1.23 ± 0.40 m/s). Principal component analysis explained 70% of the variances composed by liver stiffness increase, erythrocytes and alanine aminotransferase reduction. Brachycephalic dogs had higher spleen and liver stiffness and a subacute inflammatory state, which represent another BOAS systemic effect. Consequently, these dogs can be at higher risk of hepatic disorders compared with mesocephalic dogs, similarly to humans affected by sleep apnea syndrome.

Clinical and ultrasound variables for early diagnosis of septic acute kidney injury in bitches with pyometra.

The aetiology of septic acute kidney injury (AKI) is not completely elucidated. Early identification of AKI in septic patients is considered to improve survival rate since it allows rapid treatment onset. We evaluated clinical, haematological, urinary, B-mode, spectral Doppler, and contrast-enhanced ultrasound variables in 20 bitches with pyometra as sepsis models and 12 healthy controls. All animals with pyometra presented some degree of renal damage on histological examination; however, sequential organ failure assessment (SOFA) classified only 40% cases with sepsis. AKI derived from systemic infection was identified in 57% of cases with hypoperfusion and in 22% with inflammation, being an affection of multifactorial origin. Among the evaluated parameters, urinary protein/creatinine ratio >0.15, serum albumin <2.94 mg/dL, time-averaged minimum velocity <21.5 cm/s, renal length/aorta diameter ratio >5.93, pulsatility index >1.53, haematocrit <45%, time-averaged maximum velocity <45.7 cm/s, haemoglobin <16 g/dL, leukocytes >12.53 × 103/uL, and cortical contrast peak intensity <69%, in the order of accuracy, are significant indicators of septic AKI with an accuracy >80%. Thus, AKI is a very prevalent condition in septic patients, derived mainly from changes in renal perfusion and inflammation. Additionally, reviewing the SOFA score parameters is suggested to identify renal failure.

Quantitative ultrasound elastography and biometry of the bitch uterus in the early puerperium after vaginal delivery and caesarean section.

Elastography is an actual imaging method used to qualitatively and quantitatively evaluate the elastic properties of tissues. The aim of this study was to evaluate and compare uterine tissue biometry and stiffness during post-partum period in brachycephalic bitches (n = 12) after c-section (GCS; n = 8) or normal delivery (GNB; n = 4). These animals were evaluated daily by abdominal ultrasound from the day of delivery until the 10th day post-partum; measuring uterine diameter, myometrial and endometrial thickness (mm) and shear wave velocity (SWV; m/s), by B-mode and ARFI (acoustic radiation force impulse) elastography, respectively. Uterine diameter was higher (p = .012) in animals submitted to c-section (15.26 ± 4.73 mm) than in normal birth (12.53 ± 2.64 mm) during the first 7 days post-partum. Uterine thickness gradually involuted in both groups (p < .0001), the myometrium during the first 9 days (p = .005) and the endometrium during the first 6 days (p = .003). The myometrial and endometrial SWVs were similar between types of delivery (p = .7846 and .8273) and presented a gradual increase (p = .411; .0043, respectively), during the first 10 days post-partum. It was concluded that bitches with normal delivery had smaller uterine thickness and faster puerperal involution than submitted to c-section, while uterine tissue stiffness was similar between delivery types and increased gradually during post-partum.