Primary Urinary Bladder Tumors in Three Guinea Pigs (Cavia Porcellus).

Urinary bladder tumors are not common in guinea pigs, but case numbers being diagnosed have increased in the past years. The authors present 3 referred cases of primary urinary bladder tumors in pet guinea pigs diagnosed using diagnostic imaging (CT, radiography, and ultrasonography) and exploratory laparotomy. Excision was not possible in the first case as the tumor was located at the neck of the urinary bladder and the owner opted for intraoperative euthanasia. The second and third cases both had tumors originating from the apex of the urinary bladder. The third guinea pig went into cardiac arrest during surgery and resuscitation was unsuccessful. The tumor was removed from the urinary bladder using partial cystectomy in the second case and 1-month postsurgery ultrasonographic examination showed no signs of tumor reoccurrence. Late recognition is the main reason for a negative outcome, as by this time tumors are already large and extensive. Whenever prolonged symptoms of hematuria are present and urolithiasis has been ruled out, ultrasonography should be undertaken to determine if a urinary tumor is the cause. Rechecks should be scheduled on a regular basis for guinea pigs when a definitive diagnosis can not be made at the initial presentation for vague clinical signs, as outcome and survival can reduce significantly when definitive treatment is delayed.

Ultrasonography of the paralumbar muscles as a new aid during melarsomine treatment in canine heartworm disease. Description and illustration of the method - A preliminary study.

Melarsomine is used intramuscularly to destroy adult heartworms when treating canine heartworm disease (HWD). This drug is highly irritative and can elicit local complications. Therefore, melarsomine should be injected into the paralumbar muscles by strictly adhering to the manufacturers' prescriptions. However, it is not known how to determine the optimal location of the needle during the injection process. Ultrasonography (US) of the epaxial (paralumbar) musculature was used as a new method to measure the cross-sectional diameter of the paralumbar musculature, to determine the required location of the injection needle, and to study the local side effects in two dogs with HWD. The macroscopic appearance of the melarsomine solution during injection was demonstrated by video imaging. Melarsomine was not fully gravitating, but its majority was spreading along the thickest fascia of the musculature. Three minutes thereafter, no ultrasound signs of the melarsomine solution were seen, suggesting a full absorption at least ultrasonographically. This procedure was simulated in vitro with methylene blue solution having the same appearance. Removing the injection needle only after 5 min post-injection could prevent undesirable leakage of the drug through the injection channel into the subcutaneous tissue. Ultrasonography can be a useful aid during the treatment of HWD with melarsomine according to this preliminary study.

Two-dimensional echocardiographic measurements of the left atrium in dogs with cardiac disease.

The aim of the present study was to verify the validity of two-dimensional echocardiographic (2DE) measurement technique in dogs with left atrial enlargement. Thirty-one dogs with clinically and echocardiographically proven cardiac diseases were randomly selected. The left atrial right-to-left diameter (La(r-l)) and the diameter of the left atrium just above the mitral annulus (La(ama)) as well as the ratio of left atrial to aortic diameter ( La/Ao ) were measured by 2DE. The La (r-l) / La(ama) ratio was independent of body weight (R(2) = 0.0006) and age (R(2) = 0.0012), respectively. A significant linear relationship was found between La(ama) and La/Ao (the ratio that expresses the severity of atrial enlargement): La(ama) = 1.2238 La/Ao + 1.1608 (R(2) = 021; P < 0.01). There was also a positive linear relationship between La(r-l) and La/Ao : La(r-l) = 1.6876 La/Ao + 1.2648 (R(2) = 0.27; P < 0.005). In our dogs with cardiac disease, the La(r-l) / La(ama) ratio showed no significant relation to the La/Ao index (R(2) = 0.028). Thus, La(r-l) / La(ama) proved to be independent of the severity of atrial enlargement. Based on the strong relationship stated in the equation between La ama and La r-l [ La(r-l) / La(ama) = 1.31159 (95% confidence interval)], La(ama) can also be used for the assessment of left atrial size even in dogs with cardiac disease.