Excretory urographic, ultrasonographic, and cystoscopic characteristics of urinary bladder abscesses in a dog.

A 7-year-old male neutered, 6.5 kg, Maltese breed dog was referred with a history of dysuria after undergoing two cystotomies to remove calcium oxalate uroliths. Survey radiographs were inconclusive. Excretory urography allowed visualization of two filling defects in the cranioventral urinary bladder region. Ultrasonography showed urinary bladder sediments, a diffusely thickened wall, and two circumscribed intramural/intraluminal structures with an anechoic interior and a smooth and regular surface. The cystoscopic diagnosis was urinary bladder abscesses and urine cultures were positive for Escherichia coli. Antimicrobial/anti-inflammatory therapy was started with good clinical outcomes and negative culture after 21 days.

Urethro-venous intravasation during retrograde urethrography in a dog.

A 9-year-old 6-kg male castrated mixed-breed dog was admitted to the hospital as a second opinion for left-sided nephrectomy. Plain radiographs, ultrasound, excretory urography and retrograde urethrography revealed left-sided hydronephrosis and calculi in the bladder and urethra. The urethral calculi were hydropropulsed into the bladder and nephrectomy and cystotomy were performed. Three days after surgery, the patient showed preputial inflammation, pain and pollakiuria. Retrograde urethrography was repeated and extra-urethral leakage of contrast medium into the penile tissue was identified, followed by filling of the draining veins, reaching the caudal vena cava, with subsequent opacification of the right renal pelvis and ureter and opacification of a lymph node. The dog improved during hospitalisation and a retrograde urography performed 6 months after the initial surgery confirmed full recovery.

Comparison of static-fluid or excretory magnetic resonance urography with computed tomography urography for visualization of nondilated renal pelvises and ureters in healthy Beagles.

OBJECTIVE: To assess the usefulness of magnetic resonance urography (MRU) for the visualization of nondilated renal pelvises and ureters in dogs and to compare our findings for MRU versus CT urography (CTU). ANIMALS: 9 healthy Beagles. PROCEDURES: Dogs underwent CTU, static-fluid MRU, and excretory MRU, with ≥ 7 days between procedures. Contrast medium was administered IV during CTU and excretory MRU, whereas urine in the urinary tract was an intrinsic contrast medium for static-fluid MRU. For each procedure, furosemide (1 mg/kg, IV) was administered, and reconstructed dorsal plane images were acquired 3 minutes (n = 2) and 7 minutes (2) later. Images were scored for visualization of those structures and for image quality, diameters of renal pelvises and ureters were measured, and results were compared across imaging techniques. RESULTS: Excretory MRU and CTU allowed good visualization of the renal pelvises and ureters, whereas static-fluid MRU provided lower visualization of the ureters. Distention of the renal pelvises and ureters was good in excretory MRU and CTU. Distention of the ureters in static-fluid MRU was insufficient compared with that in CTU and excretory MRU. Distinct artifacts were not observed in CTU and excretory MRU images. Static-fluid MRU images had several mild motion artifacts. CLINICAL RELEVANCE: Our findings indicated that excretory MRU with furosemide administration was useful for visualizing nondilated renal pelvises and ureters of dogs in the present study. When performing MRU for the evaluation of dogs without urinary tract dilation, excretory MRU may be more suitable than static-fluid MRU.

Four-dimensional CT excretory urography is an accurate technique for diagnosis of canine ureteral ectopia.

Computed tomographic (CT) excretory urography is commonly used to investigate canine ureteral ectopia (UE). Modern technology allows time-resolved CT imaging (four-dimensional CT excretory urography [4D-CTEU]) over a distance exceeding the detector collimation. Objectives of this prospective, observational, diagnostic accuracy study were to evaluate the diagnostic accuracy of CT excretory urography (CTEU) and 4D-CTEU for UE in dogs with lower urinary tract signs, assess the influence of pelvis positioning, and to determine the significance of the ureterovesical junction (UVJ) angle for UE diagnosis. Thirty-six dogs, with a total of 42 normotopic ureters, 27 intramural ectopic ureters, and three extramural ectopic ureters, underwent CTEU and 4D-CTEU with randomized pelvis positioning. Randomized CTEU and 4D-CTEU studies were scored by two observers for ureteral papilla location and murality on a grading scheme. Interobserver agreement, sensitivity, and specificity for ureter topia status and diagnosis were calculated. Computed tomographic excretory urography showed moderate interobserver agreement for the left ureter and perfect for the right ureter, whereas 4D-CTEU showed bilateral nearly perfect agreement between both observers. When comparing CTEU versus confirmed diagnosis, there was a sensitivity and specificity of 73% and 90.2%, respectively, whereas 4D-CTEU showed a sensitivity and specificity of 97% and 94.6%, respectively. An obtuse UVJ angle is significantly more commonly observed in ectopic intramural than normotopic ureters and is significantly associated with increased diagnostic confidence of UE. The use of a wedge to angle the pelvis did not increase the diagnostic confidence in determining ureteral opening position. Four-dimensional CT excretory urography is an accurate and reliable diagnostic technique to investigate UE as cause of urinary incontinence in dogs that is slightly superior to CTEU.

The urethra of healthy female dogs can be normally narrowed due to the urethral flexure in retrograde CT urethrography.

Quantitative analysis of urethral size in male dogs by retrograde CT urethrography using a power injector is a recently reported technique. The aim of the current, prospective, analytical study was to apply the same method to six, healthy, intact female Beagle dogs. The proximal (P < .0001) and middle (P = .0010) urethral volumes significantly differed between the empty and distended bladder states, although no significant difference was observed in the distal volume (P = .0971). Unlike male dogs, female dogs showed two patterns of the urethral course: a straight urethra and urethral flexure. The urethral flexure was always related to intrapelvic position of the urinary bladder, and the more caudal the location of the vesicourethral junction beyond the pecten of the pubic bone, the more marked the appearance of the urethral flexure. Analysis of the urethral diameter at five sites (adopted from the previous radiographic study) was performed, and the urethral diameter showed a significant difference between the empty and the distended bladder states at sites 1 (vesicourethral junction, P < .0001), 2 (P < .0001), and 3 (P = .0244). However, there were no significant differences at sites 4 (P = .2516) and 5 (inflatable retention bulb, P = .1260). The urinary bladder may be in part intrapelvically located in clinically healthy female dogs, and urethral flexure and urethral narrowing can result from the intrapelvic location of the bladder. Narrowing of the urethra should be interpreted with caution when the pelvic bladder is identified.

Split-bolus CT urography with synchronous nephrographic and excretory phase in dogs: comparison of image quality with three-phase CT urography and optimal allocation ratio of contrast medium.

BACKGROUND: Computed tomography urography (CTU), based on the excretion of contrast medium after its injection, allows visualization of the renal parenchyma and the renal collecting system. OBJECTIVES: To determine the optimal contrast medium dose allocation ratio to apply in split-bolus CTU in dogs. METHODS: This prospective, experimental, exploratory study used 8 beagles. In 3-phase CTU, unenhanced-, nephrographic-, and excretory-phase images were obtained with a single injection of 600 mg iodine/kg iohexol. In split-bolus CTU, two different contrast medium allocation ratios (30% and 70% for split CTU 1; 50% and 50% for split CTU 2) were used. Unenhanced phase image and a synchronous nephrographic-excretory phase image were acquired. RESULTS: Although the attenuation of the renal parenchyma was significantly lower when using both split CTUs than the 3-phase CTU, based on qualitative evaluation, the visualization score of the renal parenchyma of split CTU 1 was as high as that of the 3-phase CTU, whereas the split CTU 2 score was significantly lower than those of the two others. Artifacts were not apparent, regardless of CTU protocol. The diameter and opacification of the ureter in both split CTUs were not significantly different from those using 3-phase CTU. CONCLUSIONS: Split-bolus CTU with a contrast medium allocation ratio of 30% and 70% is feasible for evaluating the urinary system and allows sufficient enhancement of the renal parenchyma and appropriate distention and opacification of the ureter, with similar image quality to 3-phase CTU in healthy dogs. Split-bolus CTU has the advantages of reducing radiation exposure and the number of CT images needed for interpretation.

Crossed renal ectopia with fusion in a pelvic inlet area, atypical portal vein and coccygeal deformation in a young female cat.

BACKGROUND: The case report describes a rare congenital anomaly, crossed fused renal ectopia (CFRE), with coexistence of two other abnormalities - atypical portal vein and coccygeal vertebrae malformation in a domestic cat. The concomitance of those 3 congenital defects has not been described previously. CASE PRESENTATION: An 8-month-old female, domestic cat suffering from chronic diarrhea was referred to the diagnostic imaging unit. The patient showed no other clinical symptoms. An abdominal ultrasonographic examination was performed in order to evaluate the condition of abdominal organs, particularly the gastrointestinal tract. The ultrasound examination showed an ectopic duplex kidney at instead of kidneys in their typical location. Computed tomography (CT) with angiographic phase and excretory urography was requested to evaluate the condition of the kidneys and ureters. The final diagnosis was CFRE, atypical portal vein and coccygeal deformation in an asymptomatic cat with no changes in renal function and normal blood parameters. CONCLUSIONS: Crossed fused renal ectopia is a rare congenital anomaly and is easily detectable by an abdominal ultrasonographic examination and CT, which allows more complete assessment of both anatomical relations and secretory function of the kidney. The occurrence of CFRE, abnormal portal vein and spinal malformation in a clinically healthy patient is the evidence that congenital malformations may simultaneously involve various, not directly related structures and systems, without significant influence on blood and urine parameters. Thus the most useful tool in the evaluation of the morphological and functional changes is the diagnostic imaging, especially contrast enhanced CT. Our results show that renal fusions should be considered in the differential diagnosis of caudal abdominal masses.

Ultrasound-guided percutaneous antegrade pyelography for suspected ureteral obstruction in 6 pet guinea pigs (Cavia porcellus).

OBJECTIVES: To describe the feasibility and safety of ultrasound-guided percutaneous antegrade pyelography (US-PAP) in pet guinea pigs (Cavia porcellus) with suspected ureteral obstruction. MATERIALS AND METHODS: Six adult pet guinea pigs (4 females and 2 males, all intact) were evaluated for suspected ureteral obstruction. The mean weight of the guinea pigs was 0.8 ± 0.25 kg (range 0.4-1.1 kg), and mean age was 4.07 ± 1.63 years (range 2-7 years). All animals were free from comorbid diseases, had clinical signs of urologic disease and were referred based on either strong clinical suspicion of, or diagnostic imaging of ureteral obstruction. Data on signalment and clinical examination findings, response to anaesthesia and imaging findings were recorded. RESULTS: Partial ureteral obstruction was confirmed in all guinea pigs but one, in which a complete ureteral obstruction occurred. Uroliths were in both ureters of 5 cases and in both the left renal pelvis and ureters in 1 case. All guinea pigs showed a normal appetite and regular defaecation within 2 h following the procedure. No intraoperative or immediate postoperative complications were encountered after the procedure. The only complication was contrast medium leakages in the subcapsular perinephric, retroperitoneal and, in one case, peritoneal space, which caused no overt clinical consequences afterwards. In one male patient, mobilisation of the ureteral calculus occurred and the urolith was found in the urinary bladder on the radiograph taken after contrast medium injection. CLINICAL SIGNIFICANCE: The US-PAP technique is a useful, safe and easy-to-perform diagnostic tool in guinea pigs with hydronephrosis and hydroureter.

Iatrogenic Urethral Trauma During Routine Prescrotal Orchiectomy in a Dog.

A 6-month-old neutered male redbone coonhound was presented for a 2-day history of progressive subcutaneous swelling that began immediately following a routine prescrotal orchiectomy. Severe, fluctuant swelling and bruising of the ventral thorax, abdomen, scrotum, and right pelvic limb was apparent on examination. No evidence of an underlying coagulopathy was detected. Azotemia and hyperkalemia were noted on venous blood gas analysis. Analysis of the serosanguineous fluid obtained from the fluctuant swelling revealed a BUN, creatinine, and potassium that were severely elevated and consistent with urine extravasation. A retrograde contrast urethrogram was performed and revealed leakage of contrast at the level of the prescrotal urethra. The dog was taken to surgery and a 2-cm longitudinal urethral defect was noted at the level of the prescrotal incision. A scrotal ablation and urethrostomy was performed, and the dog recovered uneventfully. This case highlights the diagnostic workup of a case of subcutaneous urine extravasation secondary to a urethral laceration sustained during a routine prescrotal orchiectomy. Iatrogenic urethral trauma should be considered as a differential diagnosis in dogs presenting for subcutaneous swelling with a history of recent orchiectomy surgery.

Computed tomographic and sonographic findings in a dog with duplex kidney, ureter duplex and ectopic ureterocele.

A 5-month-old, male French bulldog was presented with a history of urinary incontinence. Abdominal ultrasound showed changes compatible with a ureterocele and a bilobed right kidney. Excretory computed tomographic urography was consistent with right-sided duplex kidney, ureter duplex and ectopic ureterocele. To the authors' knowledge, this is the first description of a duplex kidney with an ectopic ureterocele diagnosed with ultrasound and contrast enhanced computed tomography in a dog. After the imaging diagnosis, a neoureterocystostomy was performed. In the follow-up examination the dog presented with mild incontinence which was treated medically using phenylpropanolamine.

Diagnostic Imaging of the Renal System in Exotic Companion Mammals.

Radiographs can be used to easily visualize common types of urinary calculi in all parts of the urinary tract. Positive-contrast excretory urography and cystourethrography are sensitive to diseases within the ureters and urethra, most commonly obstruction. Ultrasound is widely available and noninvasive and can be used to evaluate renal architecture, ureteral dilation, urinary bladder wall disease, and urolithiasis. Computed tomography is increasing in availability and provides a large amount of cross-sectional information quickly and noninvasively. Multiple imaging modalities can be used to estimate or quantify glomerular filtration rate.

Diagnostic Imaging of the Avian Urinary Tract.

Due to the special anatomy and physiology of the avian urinary system, the value of diagnostic imaging techniques differs from the use in mammals. The diagnostic imaging methods regularly used in practice to evaluate the avian kidneys are often limited to traditional radiography and ultrasonography, whereas other imaging modalities (urography, scintigraphy, computed tomography, MRI) are rarely used. Furthermore endoscopy may be performed and taking a renal biopsy may be considered. The article describes common indications for imaging techniques used to diagnose urinary tract disease as well as its anatomic and pathologic demonstration.

Computed tomographic excretory urography for diagnosing ectopic ureter in a female rhesus macaque (Macaca mulatta).

Ectopic ureter is a congenital abnormality where the ureter terminates at a site other than the urinary bladder. A five-year-old female rhesus monkey presented with a urine odor, a wet perineum, and persistent dribbling of urine. An ultrasound examination revealed a cyst-like structure (1 × 0.75 cm) on the left side of the bladder. Computed tomographic excretory urography (CTEU) imaging revealed a left unilateral extramural ectopic ureter, which was connected to the vagina. The perineum and wet hair were dried and disinfected with 0.4% chlorhexidine for perineal hygiene and skin care. The animal was closely monitored for potential moist dermatitis near the perineum and for urinary tract infection. The complete blood count (CBC) and blood chemistry results showed no signs of inflammation during the observation period. This is the first report of detailed diagnosis of ectopic ureter by ultrasound and CTEU in a female rhesus monkey.

Crossed renal ectopia with fusion in a female feline: case report / Ectopia renal cruzada com fusão em uma gata: relato de caso

A 3 year old female feline of mixed breed was sent to the diagnostic imaging sector under suspicion of bleeding due to ovariohysterectomy. An abdominal ultrasonography was performed to confirm the initial suspicion. However, no signs of bleeding were found, instead it was observed that the left renal silhouette had two pelvises and was elongated and larger than normal. The right kidney was not found. Excretory urography was requested to evaluate the condition of the ureters. The final diagnosis was crossed renal ectopia with fusion in an asymptomatic cat with no changes in renal function.(AU)

Uma gata, sem raça definida, com três anos de idade, foi encaminhada para o setor de diagnóstico por imagem sob suspeita de hemorragia devido à ovário-histerectomia. Foi realizada ultrasonografia abdominal para confirmar a suspeita inicial, mas nenhum sinal de hemorragia foi encontrado; visibilizou-se, entretanto, a silhueta renal esquerda alongada, com presença de duas pelves. O rim direito não foi encontrado. Solicitou-se exame de urografia excretora para avaliação de ureteres. O diagnóstico foi de ectopia renal cruzada com fusão em um felino assintomático e sem alterações na função renal.(AU)

Computed tomographic retrograde positive contrast cystography and computed tomographic excretory urography characterization of a urinary bladder diverticulum in a dog.

A one-year-old intact male German shepherd dog was referred with a 3-month history of dysuria and pollakiuria. Physical examination revealed a large firm mass in the caudal abdomen. Findings from survey radiography, negative contrast cystography, computed tomographic (CT) retrograde positive contrast cystography, and CT excretory urography were consistent with a large urinary bladder diverticulum. An exploratory laparotomy revealed a normal wall appearance in the ventral compartment (true bladder) and marked thinning of the wall in the dorsal compartment (diverticulum). Both ureters inserted into the ventral compartment. The dorsal compartment was excised and histopathology confirmed the diagnosis of urinary bladder diverticulum.

Description of digital fluoroscopic excretory urography in healthy New Zealand rabbits (Oryctolagus cuniculus).

Disorders of the kidneys and urinary tract are relatively common in rabbits. Survey radiographs and abdominal ultrasound have inherent limitations in the evaluation of the urinary tract in this species; because of that, contrast study modalities are a valuable diagnostic tool in rabbits with urinary disorders. The aims of this study were to describe digital fluoroscopic excretory urography (DFEU) and to determine the urogram phases in healthy New Zealand rabbits. The median time of beginning of the nephrographic and pyelographic phases was 10 seconds (IQR: 10-12 seconds) and 1.39 minutes (IQR: 1.27-1.60 minutes). The median time in which the contrast medium was visible in the urinary bladder was 1.58 minutes (IQR: 1.44-1.72 minutes). Results of this study indicate that DFEU provides a good degree of opacification of the kidneys as well as the ureters, and allows the evaluation of the urogram phases. Text not justifed in the proof version.

Description and comparison of excretory urography performed during radiography and computed tomography for evaluation of the urinary system in healthy New Zealand White rabbits (Oryctolagus cuniculus).

OBJECTIVE To evaluate the usefulness of excretory urography performed during radiography (REU) and CT (CTEU) in healthy rabbits, determine timings of urogram phases, and compare sensitivities of REU and CTEU for detection of these phases. ANIMALS 13 New Zealand White rabbits (Oryctolagus cuniculus). PROCEDURES Rabbits were screened for signs of systemic and urinary tract disease. An REU examination of each was performed, followed ≥ 5 days later by a CTEU examination. Contrast images from each modality were evaluated for quality of opacification and intervals between initiation of contrast medium administration and detection of various urogram phases. RESULTS Excretory urograms of excellent diagnostic quality were achieved with both imaging modalities. For all rabbits, the nephrographic phase of the urogram appeared in the first postcontrast REU image (obtained between 34 and 40 seconds after initiation of contrast medium administration) and at a median interval of 20 seconds in CTEU images. The pyelographic phase began at a median interval of 1.63 minutes with both imaging modalities. Contrast medium was visible within the urinary bladder at a median interval of 2.20 minutes. Median interval to the point at which the nephrogram and pyelogram were no longer visible in REU images was 8 hours and 2.67 hours, respectively. The CTEU technique was better than the REU technique for evaluating renal parenchyma. CONCLUSIONS AND CLINICAL RELEVANCE Findings suggested that REU and, particularly, CTEU may be valuable tools for the diagnosis of renal and urinary tract disease in rabbits; however, additional evaluation in diseased rabbits is required.

IMAGING DIAGNOSIS-RADIOGRAPHY AND ULTRASONOGRAPHY OF BILATERAL CONGENITAL URETEROVESICAL JUNCTION STENOSIS CAUSING HYDRONEPHROSIS AND HYDROURETER IN A FERRET (MUSTELA PUTORIUS FURO).

An 8-month-old neutered male ferret was presented for vaccination and preventive treatment for adrenal gland disease. Abdominal ultrasound revealed severe bilateral hydronephrosis and hydroureter. Excretory urography and negative contrast cystography showed bilateral ureterovesical junction stenosis. Positive retrograde cystography demonstrated right ureteral reflux. A subcutaneous ureteral bypass was placed in the left kidney; however, it had to be removed 3 months later due to an obstruction and persistent urinary tract infection. Bilateral ureteroneocystotomy was performed. Although congenital strictures are uncommon in veterinary patients, they should be included in the differential diagnosis in ferrets presenting with hydronephrosis and hydroureter of undetermined cause.

COMPARISON OF TRANSVERSE COMPUTED TOMOGRAPHIC EXCRETORY UROGRAPHY IMAGES AND MAXIMUM INTENSITY PROJECTION IMAGES FOR DIAGNOSING ECTOPIC URETERS IN DOGS.

Computed tomographic maximum intensity projection (MIP) images have been shown to improve reader confidence in their diagnoses and to improve detection of vascular structures and pulmonary nodules. The objectives of this method comparison study were to compare transverse source computed tomographic excretory urography (CTEU) images to two, five, and 10 slab thick MIP images for diagnosing canine ectopic ureters, compare reader confidence, and evaluate interobserver agreement. Two board-certified veterinary radiologists and a board-certified small animal internist blindly reviewed transverse source CTEU and two, five, and 10 slab thick MIP images of 24 dogs enrolled in the study. Inclusion criteria included a diagnostic CTEU and either cystoscopic or surgical confirmation of the presence or absence of ureteral ectopia. Eleven dogs were confirmed to have 17 ectopic ureters at surgery and/or cystoscopically. There was no significant difference in reader diagnoses between viewing methods or between viewing methods and the surgical/cystoscopic findings (P < 0.001). Reader confidence was significantly greater on two (P = 0.0080) and five (P = 0.0009) slab thick MIP images with significant interobserver agreement between readers for all viewing methods (P values ranging between 0.0363 and <0.001). In addition, the diagnostic accuracy of MIP images was similar to or better than transverse source CTEU images, when assessed by a radiologist. The study results suggest that CTEU is a reliable imaging technique for diagnosing canine ectopic ureters among specialists of varied experience. In addition, thin slice reconstructed MIP images improve reader confidence and potentially diagnostic accuracy, and thus their use should be considered, especially in more challenging cases.

RADIOGRAPHIC AND ULTRASONOGRAPHIC ABDOMINAL ANATOMY IN CAPTIVE RING-TAILED LEMURS (LEMUR CATTA).

The ring-tailed lemur (Lemur catta) is primarily distributed in south and southwestern Madagascar. It is classified as an endangered species by the International Union for Conservation of Nature. Various abdominal diseases, such as hepatic lipidosis, intestinal ulcers, cystitis, urinary tract obstruction, and neoplasia (e.g., colonic adenocarcinoma and cholangiocarcinoma), have been reported in this species. The aim of this study was to describe the normal radiographic and ultrasonographic abdominal anatomy in captive ring-tailed lemurs to provide guidance for clinical use. Radiography of the abdomen and ultrasonography of the liver, spleen, kidneys, and urinary bladder were performed in 13 and 9 healthy captive ring-tailed lemurs, respectively, during their annual health examinations. Normal radiographic and ultrasonographic reference ranges for abdominal organs were established and ratios were calculated. The majority (12/13) of animals had seven lumbar vertebrae. The sacrum had mainly (12/13) three segments. Abdominal serosal detail was excellent in all animals, and hypaxial muscles were conspicuous in the majority (11/13) of animals. The spleen was frequently (12/13) seen on the ventrodorsal (VD) view and rarely (3/13) on the right lateral (RL) view. The liver was less prominent and well contained within the ribcage. The pylorus was mostly (11/13) located to the right of the midline. The right and left kidneys were visible on the RL and VD views, with the right kidney positioned more cranial and dorsal to the left kidney. On ultrasonography, the kidneys appeared ovoid on transverse and longitudinal views. The medulla was hypoechoic to the renal cortex. The renal cortex was frequently (8/9) isoechoic and rarely (1/9) hyperechoic to the splenic parenchyma. The liver parenchyma was hypoechoic (5/5) to the renal cortex. Knowledge of the normal radiographic and ultrasonographic abdominal anatomy of ring-tailed lemurs may be useful in the diagnosis of diseases and in routine health examinations.