Although there have been many human medical reports of scattering dose and scattered radiation distributions in the computed tomography (CT) room, the investigations of specific scattering doses during veterinary CT imaging have not been reported. In this study, CT scattering doses in an examination room were measured during CT examinations in an animal hospital. Scattered radiation spatial mapping of the CT room from the routine acquisition settings that are used in actual clinical practice was performed for head, chest, abdomen, and pelvic measurements. Mapping measurements were carried out in four planes (50, 100, 150, and 200 cm above the floor) at a total of 260 locations. The largest scattering dose (133 μSv) was recorded on the bed at 50 cm caudal to the gantry center during pelvic measurements. In addition, the scattered radiation was greatest at a height of 100 cm from the floor and became progressively smaller over 150, 50, and 200 cm from the floor. The gantry side showed the smallest scattering dose. A 100-cm square of the gantry had a large scattering dose that became smaller as the distance from the bed increased. The effective dose experienced by the assistant who was using a protective apron was 3.9 μSv, which is in compliance with the ICRP recommendations for assistants who analyze less than 64 patients per year.
An eight-month-old kitten with growth retardation was admitted to the hospital due to regurgitation after food ingestion. Barium contrast X-ray examination revealed esophageal dilatation at the cranial part of the heart, and CT was performed further detailed examination. On the basis of the findings, the cat was diagnosed with an esophageal stricture due to abnormal vascular rings, and esophageal dilatation at the cranial part of the stenotic portion was observed. The abnormal vascular was resected after the cat’s condition stabilized. Five days after operative care with nasal tube feeding, the feline was discharged from the hospital. On the seventh-ninth day after the operation, the cat’s regurgitation drastically decreased.
An 11-years-old intact female Chihuahua was diagnosed with mitral valve insufficiency of ACVIM classification stage C. The dog developed hyponatremia and received tolvaptan, a selective vasopressin V2 receptor antagonist. The plasma sodium concentration increased from 134 mmol/l before administration to 147 mmol/l seven weeks after tolvaptan administration. After the administration of tolvaptan, echocardiography showed that the left ventricular end diastolic diameter and E/Em decreased from 29.9 mm to 27.8 mm and from 19.0 to 11.6, respectively. These results indicate that the water diuretic effect of tolvaptan simultaneously reduced the left ventricular preload and normalized the electrolyte level.
Prognostic indicators of echocardiography have been suggested in dogs with mitral regurgitation (MR) due to congestive heart failure. However, it is difficult to perform immediate echocardiography in dogs with acute cardiogenic pulmonary edema. In the present study, factors apart from echocardiographic indicators, which correlated with the survival time after administration of pimobendan, were studied retrospectively in dogs with MR and cardiogenic pulmonary edema. Twenty-five dogs were examined. With or without cough (P < 0.01), the intensity of the cardiac murmur (P < 0.01) and diffuse pulmonary edema (P < 0.05) on initiation of pimobendan, and duration of diuretics administration before pimobendan (P < 0.05), were related significantly to the survival time. The survival time in dogs with diffuse pulmonary edema was significantly shortened compared to that in dogs with non- diffuse pulmonary edema (219 and 883 days, respectively; P < 0.01). Therefore, it is necessary to consider these parameters as prognostic indicators on starting pimobendan administration.