Contrast‐enhanced voiding urosonography: A new,radiation‐free,alternative method for imaging of urinary bladder and urethra in healthy dogs

Contrast‐enhanced voiding urosonography (CE‐VUS) has been generally considered as a promising tool to diagnose vesicoureteral reflux and abnormalities in lower urinary tract in human patients, especially in children. The purpose of this prospective study is to evaluate the quality of images of the urinary bladder and urethra obtained by CE‐VUS using a second‐generation ultrasound contrast agent (SonoVue®) in healthy dogs and to investigate the safety profile of SonoVue® after intravesical administration. Eighty‐four CE‐VUS examinations with SonoVue® were successfully performed in both unsedated (39/84) and sedated (45/84) dogs. Contrast‐enhanced voiding urosonography examination of urinary bladder was technically successful in all (84/84) dogs. The image quality was not considered adequate in five (5/84) dogs including three dogs in whom layering of contrast media during filling phase was observed and two dogs with premature destruction of microbubbles. In these five dogs, the problem was readily recognized and corrected such that the procedure was still successfully undertaken. The assessment of the urethra during spontaneous micturition was successfully performed in all (84/84) dogs in whom voiding was elicited during the examination. No side effects were observed after intravesical application of SonoVue®. This study demonstrates that CE‐VUS is a feasible and valuable technique to evaluate low urinary tract morphology and function in dogs. Based on our review of the literature, there are no published reports about the use of this method in dogs.     

Normal and abnormal ultrasonographic findings that mimic small intestinal intussusception in the dog

On ultrasonographic examination of the abdomen, the appearance of healthy intestine, enteritis secondary to an intestinal foreign body, and postpartum involution of the uterus may be visualized in some imaging planes as a target-like structure that is subsequently misinterpreted as intestinal intussusception. To avoid misdiagnosis, the ultrasonographer should ensure multi-plane scanning of the lesion, paying particular attention to the completeness of the lesion's peripheral ring structure and the overall width of the concentric rings of the target-like lesion. The presence of a semilunar or G-shaped hyperechoic center and the visualization of the inner intussusceptum (extending into the intussusception lumen) can be useful ultrasonographic findings that distinguish an intussusception from other lesions or from healthy tissues. These principles are illustrated through the following case presentations.     

Ultrasonographic findings of intestinal intussusception in seven cats

The medical records of seven cats with intestinal intussusception that were diagnosed by abdominal ultrasonography and exploratory laparotomy were reviewed. In transverse ultrasonographic sections the intussusception appeared as a target-like mass consisting of one, two or more hyperechoic and hypoechoic concentric rings surrounding a C-shaped, circular or non-specific shaped hyperechoic centre. Part of the intestine representing the inner intussusceptum, located close to the hyperechoic centre and surrounded by concentric rings, was also detected. In longitudinal sections the intussusception appeared as multiple hyperechoic and hypoechoic parallel lines in four cases and as an ovoid mass in three cases. In one case the ovoid mass had a ‘kidney’ configuration. Additional ultrasonographic findings associated with intestinal intussusception included an intestinal neoplasm in one cat. The results of the present study demonstrate that the ultrasonographic findings of intestinal intussusception in cats bear some similarities to those described in dogs and humans, are relatively consistent, and facilitate a specific diagnosis.     

Retroperitoneal Abscess Associated With a Migrating Grass Awn in a Cat: Treatment With Omentalization and Grass Awn Removal

An 18-month-old domestic short hair male castrated cat presented with a history of fever of unknown origin of 1-year duration. Abdominal ultrasound revealed a mixed echogenicity mass. Cytological examination of the fluid obtained through fine needle aspiration was consistent with a retroperitoneal abscess. The cat underwent a midline celiotomy and the abscess was opened, lavaged, and omentalized. Antibiotics were also administered. Two months after surgery, the cat represented with a fluctuant swelling in the right flank region at the lumbodorsal triangle. Abdominal and mass ultrasound showed a mixed echogenicity swelling in the right flank. Under gas anesthesia, the swelling was surgically explored and a 0.4 cm long grass awn was found and removed. Telephone communication with the owners 6 months after surgery found the cat to be free of clinical signs.