Doppler ultrasound of the prostate in normal dogs and in dogs with chronic lymphocytic-lymphoplasmocytic prostatitis

Diseases of the Canine Prostate Gland

In dogs, the most frequent diseases of the prostate gland are benign prostate gland hyperplasia (BPH), acute and chronic prostatitis, squamous metaplasia, and prostate tumors. New diagnostic tools comprise diagnostic markers in the blood and urine, as well as advanced imaging methods. The therapy can be initialized with the 5α-reductase-inhibitor finasteride or an anti-androgenic compound, and prolonged with a long-acting gonadotropin-releasing-hormone (GnRH)-agonist such as deslorelin. In case of prostatitis, effective antibiotics must be applied for weeks. Antibiotics must be able to penetrate into the prostate tissue; fluoroquinolones, clindamycin, and erythromycin are good choices and are in addition effective against mycoplasms. The chronical prostatitis cannot be differentiated from a neoplasia by sonography; a biopsy, histological, and bacteriological examination are required. Tumors of the prostate gland are seldom and mostly occur in castrated but in intact dogs. For the final diagnosis, a biopsy must be taken. Partial and total resection of the prostate gland by use of laser technique is possible but coincedes with many side effects and the prognosis is still futile. Immunotherapy combined with NSAIDs, targeted noninvasive thermotherapy, BRAF gene inhibitors, or prostate artery chemoembolization are promising methods.

Lymphoplasmacytic prostatitis associated with urethral obstruction in a dog; a case report

A 10-year-old, male intact, mixed breed dog was admitted with a history of intermittent lower urinary tract signs of eighteen-months duration. Dysuria, stranguria, pollakiuria and overflow incontinence developed 2 weeks prior to presentation, while vomiting, polydipsia and anorexia were seen a few days prior to admission. Physical examination revealed prostatomegaly. Biochemistry results were compatible with postrenal azotemia. Abdominal imaging confirmed prostatomegaly with consequent urethral obstruction, and ultrasound-guided fine needle aspiration cytology of the prostate gland was consistent with granulomatous inflammation. The dog was hospitalized, urethral patency was preserved and upon laparotomy a cystostomy tube was placed, and prostatic biopsy was obtained. Orchiectomy was also performed. Urine culture performed two days prior to the surgery was negative. Prostatic histopathology revealed mild to moderate lymphoplasmacytic prostatitis. Three months postoperatively, clinical signs had resolved completely and urinations remained normal while the dog is still in good health three years after diagnosis. This is the first case of canine lymphoplasmacytic prostatitis in which clinical signs, diagnostic evaluation, management and long-term follow up are available.

Correlation of Prostatic Artery Blood Flow Assessed by Doppler Ultrasonography with Semen Characteristics in Beagle Dogs

Simple Summary

This study examined the blood flow parameters of the prostate artery before dog ejaculation assessed by pulsed-wave Doppler ultrasound (PwD) changes. The main objective of this study was to characterize the vascular parameters of the prostatic artery in beagle dogs and to explore the potential use of Doppler ultrasonography as a complementary method in dog stud selection. These findings report differences between blood flow parameters in cranial and caudal locations of the prostatic artery in comparison to subcapsular and parenchymal locations. There was a high positive correlation of peak systolic velocity with total volume and sperm concentration. In conclusion, estimation of the PwD parameters of the cranial prostatic artery may be useful in the breeding evaluation of dogs.

Abstract

Pulsed-wave Doppler ultrasonography (PwD) is a method used to rapidly and noninvasively assess blood flow dynamics of the canine prostate. Modifications in gland vascularization can affect seminal plasma production and consequently sperm quality. The aim of this study was to determine the normal blood flow parameters of the prostate artery in beagle dogs and to analyze the correlations between vascular flow and semen quality characteristics. PwD was performed on five beagle dogs (5–6 years) measuring vascular features in four different locations of the prostatic artery (cranial, subcapsular, parenchymal and caudal); the measured features were peak systolic velocity (PSV), end-diastolic velocity (EDV), resistive index (RI) and pulsatility index (PI). Ejaculates were obtained using digital manipulation and semen quality was evaluated by determining macroscopic (total volume, sperm-rich fraction volume, color and pH) and microscopic (sperm motility, morphology, viability and acrosome integrity) characteristics. The values of PSV, PI and RI in cranial and caudal prostatic arteries were significantly higher than in subcapsular and parenchymal arteries (p < 0.05). Moreover, a positive correlation of PSV value in the cranial region of the prostatic artery with total ejaculate volume (p < 0.01, r = 0.612) and sperm concentration (p < 0.01, r = 0.587) was determined. PI index was negatively correlated with sperm concentration (p < 0.01, r = −0.709). In conclusion, the results suggest that the prostatic artery blood flow parameters can affect macroscopic semen quality characteristics in healthy dogs.

Semen collection, sperm characteristics and ultrasonographic features of reproductive tissues in crab-eating fox (Cerdocyon thous)

Our objective was to condition adult male crab-eating fox (Cerdocyon thous) to allow semen collection by digital manipulation of the penis, assess sperm characteristics, and use ultrasonography to assess and measure testes and prostate and determine echotexture, as well as hemodynamics of testicular and spermatic cord arteries. Five captive C. thous (2-5 y, ∼7 kg) were used. After conditioning for digital sperm collection, 13 ejaculates were obtained from two males. Ejaculate characteristics (mean ± SD) were volume (393.2 ± 178.0 μL), concentration (463.7 ± 594.4 × 106 sperm/mL), total sperm number (217.4 ± 304.0 × 10⁶ sperm), total motility (68.0 ± 6.1%), progressive motility (48.8 ± 5.1%) and rapid sperm (57.2 ± 6.8%). The most prevalent sperm morphological defects were abnormal acrosome, small abnormal head, and diadem defect. Under chemical restraint, testes and prostate were evaluated with B-mode and spectral Doppler ultrasonography. Based on ultrasonography, testicular volumes were (2.2 ± 0.7 and 2.1 ± 0.7 cm³ for left and right testes, respectively), whereas prostate dimensions were 2.3 ± 0.4 cm long and 1.5 ± 0.3 cm thick. Lastly, using triplex Doppler, peak systolic velocity (PSV) was higher in testicular versus intratesticular arteries. In conclusion, adult male C. thous were conditioned to allow sperm collection by digital manipulation without urine contamination, enabling evaluation of sperm characteristics. Furthermore, B-mode ultrasound facilitated evaluation of testes and prostate morphometry and echotexture, whereas Doppler was used to characterize testicular blood flow. This was proof of concept for semen collection and baseline data for future male reproductive soundness examinations and development of assisted reproductive techniques in this species.

Imaging of the male reproductive tract: Not so easy as it looks like

Diagnostic imaging is one of the most important tools in the breeding soundness evaluation of dogs and cats with reproduction problems. In recent years several imaging techniques have been developed, trying to aid the diagnosis and to differentiate between abnormal findings. This review presents the current knowledge on the imaging of normal and abnormal testes, spermatic cord, excurrent duct system, scrotum, accessory sex glands, penis and muscles for protrusion, erection and ejaculation of the dog and of cat. It also highlights the weak points and disadvantages of each imaging technique.

Changes in the Serum Prostatic Biomarkers During the Treatment of Benign Prostatic Hyperplasia with a 5alpha-reductase Inhibitor: Finasteride

The monitoring of serum prostatic biomarkers during the treatment will help clinicians to know the statement of the response to finasteride in dogs affected by benign prostatic hyperplasia (BPH). The present study was aimed to assess changes in the serum canine prostate-specific esterase (CPSE), prostate-specific antigen (PSA), prostatic acid phosphatase (PAP), testosterone, dihydrotestosterone (DHT) and prostate volume evaluation using ultrasonographic examination during the treatment with finasteride in BPH-induced dogs. Twenty dogs were divided into 4 groups (n = 5): BPH + finasteride group, dogs which were induced for BPH and received oral finasteride once daily for 1 month; BPH group, dogs which were induced for BPH and received placebo; finasteride group, normal dogs which received finasteride; and normal group, normal intact dogs which did not receive treatment. Blood sampling and ultrasonography examination were performed on days 0, 14, and 28. The administration of finasteride led to a significant decrease in the concentration of the prostate-specific biomarkers (PSA, CPSE), DHT, testosterone, and the volume of the prostate in BPH + finasteride group compared with the BPH group during 1 month. Interestingly, the PAP concentration did not change in the BPH-induced dogs and in dogs treated with finasteride. It seems that the monitoring of serum PSA and CPSE levels and ultrasonographic examination of the prostate are useful methods for following up the response to finasteride treatment in dogs affected by BPH.

Use of transrectal ultrasonography for assessment of the size and location of prostatic carcinoma in dogs

OBJECTIVE

To evaluate the use of transrectal ultrasonography (TRUS) for the assessment of prostatic tumors in dogs and to compare results for TRUS with results for other imaging modalities.

ANIMALS

10 client-owned male dogs.

PROCEDURES

Client-owned dogs identified with prostatic carcinoma were enrolled. Fluoroscopy, transabdominal ultrasonography (TAUS), TRUS, and MRI were performed on all dogs. Tumor measurements, urethral penetration (identification of abnormal tissue within the urethral lumen), and tumor extension into the urinary tract were recorded for all imaging modalities. Agreement between results for MRI (considered the criterion-referenced standard) and results for other modalities were compared.

RESULTS

Median body weight of the 10 dogs was 26.3 kg (range, 9.4 to 49.5 kg). No complications were encountered during or after TRUS. Significant moderate to good agreements (intraclass correlation coefficients, 0.60 to 0.86) among TAUS, TRUS, fluoroscopy, and MRI were identified for tumor length and height. Assessments of urethral penetration and tumor extension into the bladder with TRUS did not differ significantly from those made with MRI and were superior in terms of absolute agreement with MRI when compared with those for TAUS.

CONCLUSIONS AND CLINICAL RELEVANCE

TRUS was successfully and safely used to evaluate prostatic carcinoma in dogs. There was moderate to good agreement with MRI results for tumor height and length measurements, and TRUS was found to be superior to TAUS for some assessments. Transrectal ultrasonography can be considered an adjunctive imaging modality for the performance of prostatic interventional procedures or assessment of response to treatment.

Advanced ultrasound techniques in small animal reproduction imaging

Ultrasonography is the imaging technology of choice for the evaluation of the reproduction system and of pregnancy in both humans and animals. Over the past 10 years, there have been significant technological improvements of the equipment, while new technologies have been developed. Doppler, contrast-enhanced ultrasonography, elastography, and 3D/4D ultrasonography are advanced ultrasound techniques that have been designed as methods to increase the diagnostic sensitivity of two-dimensional (b-mode) ultrasound, and not as stand-alone tests. The basic physics as well as the advantages and limitations of these advanced ultrasound methods are briefly described. In the reproductive diagnostics of small animals, these techniques have gained an increased popularity as proved by the increased publication of several reports that are also briefly summarized in this review. Clinical applicability is to date limited because of a lack of research on the diagnostic value in concrete situations. Future research projects should focus also on standardization of the used techniques, on determination of thresholds to discriminate between healthy or diseases or fertile versus infertile and on the predictive value of advanced ultrasound findings. Continuing development and optimization of different ultrasound techniques as well as the increase of related scientific interest and worldwide research promises that the clinical interest on the use of advanced ultrasound techniques will increase in future.

Ejaculation effect on blood testosterone and prostatic pulsed-wave Doppler ultrasound in dogs

Local vessels ultrasonography evaluates prostatic physio-pathologic states. Testosterone promotes tissue and vascular growth. Knowing variables on prostatic vasculature is crucial to correctly apply Pulsed-Wave exam. The study aims to assess how ejaculation and blood testosterone affect Pulsed-Wave indexes. Serial blood testosterone dosages and Pulsed-Wave exams were performed in 20 dogs, immediately before (T0) and after (T1) ejaculation and 6 hr later (T2). Arteria prostatica cranialis, Arteriola capsularis, Arteriola trabecularis and Arteriola parenchimalis were evaluated and mean Pulsatility and Resistivity Index, Systolic-Peak, End-Diastolic and Mean Velocity calculated. Data were grouped by time and vessel (ANOVA, p ≤ 0.05). At T1, Resistivity Index significantly lowered in A. prostatica cranialis, A. trabecularis and A. parenchimalis but grew in A. capsularis; Pulsatility Index had the same pattern, but not significant in A. parenchimalis; Systolic Peak Velocity, End-Diastolic Velocity, Mean Velocity significantly rose in A. capsularis and A. trabecularis. No indexes differed at T0 and T2. Testosterone did not differ at T0 (10.93 ± 7.05 ng/ml), T1 (12.71 ± 7.29) and T2 (10.54 ± 6.63). Results stated the risen prostatic vascular flow postejaculation, affecting Pulsed-Wave. Due to semi-rigid capsule, impairing vasodilation of other vessels, only A. capsularis indexes increased. Intimal cushions of A. prostatica cranialis kept velocities fixed; A. capsularis and A. trabecularis lack of intimal cushions, thus velocities grew. In A. parenchimalis, precapillary sphincters opening allows increased flow redistribution in vasodilated parenchymal bed, keeping velocities fixed. As testosterone, not affected by ejaculation, did not peak, vascular changes are not due to testosterone itself. These physiological effects of ejaculation suggest proper sexual rest before Pulsed-Wave exam planned to explore suspected prostatic neovascularization.

Canine prostate specific esterase (CPSE) as an useful biomarker in preventive screening programme of canine prostate: CPSE threshold value assessment and its correlation with ultrasonographic prostatic abnormalities in asymptomatic dogs

Due to the increased attention that pet-owners devote to their animals and to the improved veterinary care, investigations regarding methods to early detect prostatic disorders that might affect canine life quality have been performed. Canine prostate specific esterase (CPSE) concentration was reported to be higher in dogs suffering from prostatic diseases. This study aimed to estimate the CPSE threshold as a biomarker to early identify prostatic diseases in asymptomatic dogs. The ultrasonographic examination of the prostate was performed in 19 dogs (6-40 kg; 1-5 years) with no symptoms of prostatic diseases. Dogs were grouped according to the presence (Group A) or absence (Group B) of prostatic disorders at the ultrasound (altered appearance, the presence of cysts or irregular borders). For each dog, a venous blood sample was collected to measure serum CPSE and the ratio between calculated and normal expected prostatic volume was assessed for each dog. The CPSE data were statistically analysed (t test, p < .05), and the CPSE threshold in blood serum between groups was calculated by ROC. In 11 dogs, ultrasonography showed signs of prostatic abnormalities (Group A, 2-5 years), while no signs were detected in eight dogs (Group B, 1-3 years). The calculated/estimated volume ratio resulted greater than 1.5 in Group A dogs. The CPSE was statistically different between groups (p < .0001): higher in Group A (mean = 184.9, SD = 126 ng/ml) than in Group B (38.9 ± 22.1 ng/ml). The cut-off CPSE threshold was 52.3 ng/ml (ROC, AUC = 0.974, SE 95.6%, SP 89.2%). This study suggests that CPSE serum concentration higher than 50 ng/ml in asymptomatic dogs is associated with ultrasonographic alterations and increased the prostatic size (volume by 1.5 times greater than the normal size). As the onset of prostatic disorders often remains asymptomatic, the rapid assessment of CPSE could be suitable for selecting preventively those animals that would require further accurate evaluation.

Diagnosis of common prostatic conditions in dogs: an update

Prostatic diseases account for 3-10% of intact male dogs presented to veterinary surgeons. Conditions vary according to severity and frequency ranging from the most common, such as prostatic hyperplasia and cysts to the rarer conditions such as prostatic abcesses and neoplasia. Different causes of prostatic disease can often not be distinguished by evaluation of clinical signs, as these are not very distinctive and may be similar for many prostatic conditions. Understanding which additional diagnostic tools to use for each of the possible conditions is essential in making a correct diagnosis leading to the proper treatment. This article will discuss the different etiologies, age groups of dogs and the decision-making process which will help the practitioner to choose the right investigative tools, treatments and prognosis when dealing with prostatic disease.

Human prostate cancer risk factors

Prostate cancer has the highest prevalence of any nonskin cancer in the human body, with similar likelihood of neoplastic foci found within the prostates of men around the world regardless of diet, occupation, lifestyle, or other factors. Essentially all men with circulating androgens will develop microscopic prostate cancer if they live long enough. This review is a contemporary and comprehensive, literature-based analysis of the putative risk factors for human prostate cancer, and the results were presented at a multidisciplinary consensus conference held in Crystal City, Virginia, in the fall of 2002. The objectives were to evaluate known environmental factors and mechanisms of prostatic carcinogenesis and to identify existing data gaps and future research needs. The review is divided into four sections, including 1) epidemiology (endogenous factors [family history, hormones, race, aging and oxidative stress] and exogenous factors [diet, environmental agents, occupation and other factors, including lifestyle factors]); 2) animal and cell culture models for prediction of human risk (rodent models, transgenic models, mouse reconstitution models, severe combined immunodeficiency syndrome mouse models, canine models, xenograft models, and cell culture models); 3) biomarkers in prostate cancer, most of which have been tested only as predictive factors for patient outcome after treatment rather than as risk factors; and 4) genotoxic and nongenotoxic mechanisms of carcinogenesis. The authors conclude that most of the data regarding risk relies, of necessity, on epidemiologic studies, but animal and cell culture models offer promise in confirming some important findings. The current understanding of biomarkers of disease and risk factors is limited. An understanding of the risk factors for prostate cancer has practical importance for public health research and policy, genetic and nutritional education and chemoprevention, and prevention strategies.

Extraglandular and intraglandular vascularization of canine prostate

The literature on the vascularization of the canine prostate is reviewed and the clinical significance of prostate morphology is described. Scanning Electron Microscopy (SEM), combined with improved corrosion casting methods, reveal new morphological details that promise better diagnostics and treatment but also require expansion of clinical nomenclature. A proposal is made for including two previously unnamed veins in Nomina Anatomica Veterinaria (NAV). The canine prostate has two lobes with independent vascularization. Each lobe is supplied through the left and right a. prostatica, respectively. The a. prostatica sprouts three small vessels (cranial, middle, and caudal) towards the prostate gland. A. prostatica is a small-size artery whose wall structure is similar to the arteries of the muscular type. V. prostatica is a small-size valved vein. The canine prostate has capsular, parenchymal, and urethral vascular zones. The surface vessels of the capsule are predominantly veins and the diameter of arterial vessels is larger than that of the veins. The trabecular vessels are of two types: direct and branched. The prostate parenchyma is supplied by branches of the trabecular vessels. The periacinary capillaries are fenestrated and form a net in a circular pattern. The processes of the myoepithelial cells embrace both the acins and the periacinar capillaries. In the prostate ductal system. there are spermatozoa. The prostatic part of the urethra is supplied by an independent branch of a. prostatica. The prostatic urethral part is drained by v. prostatica, the vein of the urethral bulb and the ventral prostate veins. M. urethralis begins as early as the urethral prostatic part. The greater part of the white muscle fibers in m. urethralis suggest an enhanced anaerobic metabolism.

Normal duplex Doppler waveforms of major abdominal blood vessels in dogs: a review

The normal flow velocity profile and duplex Doppler waveform of the major abdominal blood vessels (aorta, caudal vena cava and the portal vein as well as their major branches) were examined by Doppler ultrasound. The flow velocity profile of an artery is largely determined by its diameter. The pulsatility of the waveform is related to the vascular impedance downstream to the point of measurement. Early systolic peak is present in the Doppler pattern of some vessels in some dogs. The waveform of the veins is mainly affected by the pressure conditions of the right atrium and the intrathoracic and intraabdominal pressure changes due to the respiration. Simultaneous electrocardiogram was used to reveal the effect of the heart beats on the Doppler patterns of the veins.