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51.
PREGNANCY DIAGNOSIS WITH ULTRASOUND IN THE DOMESTIC CAT   总被引:1,自引:0,他引:1  
Ultrasonographic examinations of seven pregnant cats with known breeding dates were made on successive days to establish the identifiable characteristics of pregnancy. Subsequent serial examinations were made to sonographically characterize normal feline prenatal development before 30 gestational days. An enlarged uterus, gestational sacs, and fetal poles were recognized as the features of early feline pregnancy and were first seen at 4, 11, and 15 days, respectively. Cardiac activity was detected earliest on gestational day 16, and recognizable feline fetal morphology appeared at day 26. Fetal membranes became apparent at as early as 21 days of gestation. Generalized fetal movements were first noted at day 28. Live and dead fetuses were compared in utero and marked differences were noted, with dead fetuses rapidly losing previously recognizable morphology. Determination of litter size in each cat could not be done accurately by ultrasound examination. It was concluded that the diagnosis and accurate dating of early pregnancy in the domestic feline may be accomplished with serial ultrasound evaluation.  相似文献   
52.
The uptake and washout of iodinated contrast medium in neoplastic and non-neoplastic lesions in the dog brin was quantified using computed tomography. The magnitude of tissue contrast enhancement was measured during and up to 15 minutes following an intravenous infusion of contrast medium. Compartmental analysis was used to obtain rate contants for contrast medium movement into and out of brain lesions. In non-glioma tumors, contrast enhancement was maximum during the infusion and the rate of contrast washout was comparable to that measured in the normal brain. Mixed gliomas also showed maximum enhancement during infusion, but there was no washout of contrast. Contrast enhancement in radiation-induced brain damage and cystic encephalomalacia secondary to tumor compression continued to increase for 5–15 minutes after infusion; rate constants in these non-tumor lesions were different from all tumors studied. Hyperthermia-induced lesions had comparable rate constants for contrast washin and washout. These results indicate that kinetic CT studies provide a non-invasive measure of permeability differences between lesions, may be useful in differentiating certain types of intracranial lesions, and may provide an effective method for patient follow-up after treatment.  相似文献   
53.
Radiation treatment requires a precise procedure for interfraction repositioning of the patient. The purpose of this study was to determine the accuracy of our fixation device in treatment position and to evaluate the setup accuracy with two different methods. The positioning data of 19 canine patients with tumors in the head region (oral, nasal, cerebral) treated with photon or proton irradiation were included in this study. The patients were immobilized by means of an individualized fixation device. Focus was set upon interfraction displacement with systematic and random components. In one method, treatment position was evaluated using single plane port radiographs and megavoltage x-rays. In the other method, two orthogonal CT-topograms were acquired to evaluate the precision of positioning of the patient in the immobilization device. Systematic and random displacements were calculated and presented as mean values with corresponding 95% confidence intervals. In spite of a difference between both methods, the positioning seemed to be accurate within the expected range. It seems that a safety margin of 3.7 mm would be enough for both methods to take into account systematic and random position variability in the fixation device, thereby preventing geometric inaccuracies of treatment delivery. The reported immobilization protocol provides accurate patient immobilization for photon and conformal proton radiation therapy.  相似文献   
54.
Gastrointestinal contrast studies were performed in six clinically healthy blue-fronted Amazon parrots (Amazona aestiva) using radiography and image-intensified fluoroscopy. During examination, the birds were confined in a perspex cage. The quality of the lateral radiographs was adequate for assessment of the contrast medium-filled gastrointestinal tract. Thirty minutes after administration of 20 mL/kg of a 25% barium sulphate suspension directly in the crop, in all birds the ventriculus was totally outlined by barium. After 60 min, the small intestine was filled in five of six birds. After 180 min, the crop was empty in all birds. The barium-outlined ventriculus had differences in shape on radiographs of individual birds and also between birds. The colon and cloaca had further filling after 120 to 300 min. With image-intensified fluoroscopy, gastrointestinal motility was evaluated. Contractions of the crop were seen, and boluses of contrast medium passing through the esophagus toward the proventriculus were easily identified. Proventricular contractions were rarely noted, but ventriculus motility was present and clearly defined. The ventriculus had a mean of 3.7 contraction cycles/min. In the duodenum and small intestine, rapid antegrade and retrograde peristaltic movements in combination with segmental contractions were seen. In the colon, occasionally very slow peristaltic activity, mainly of segmental nature, was present. During the examinations, no defeacation was recorded. Confinement in a small perspex cage provides an adequate and handy radiological set-up for evaluation of gastrointestinal passage and motility in birds, minimizing the influences of stress and anesthesia.  相似文献   
55.
The results of radiographic examination of clinically affected elbow joints in 14 young, large-breed dogs, including standard and oblique projections and linear tomography, were compared with the findings of medial arthrotomy. Radiographs revealed arthrosis (13 dogs), osteochondrosis of the medial humeral condyle (2 dogs), fragmentation of the medial coronoid process (5 dogs), and a combination of osteochondrosis of the medial humeral condyle and fragmentation of the medial coronoid process (2 dogs). In one dog fissures in the medial coronoid process and in another dog a linear radiopacity along the articular surface of the medial coronoid process were found. In three dogs both medial humeral condyle and medial coronoid process appeared normal. The radiographic findings were confirmed during surgery in 11 dogs. Cartilage erosion of the medial humeral condyle in two dogs and of the medial coronoid process in one dog had not resulted in radiographically visible abnormalities. Radiographic examination of the elbow joints in young, large-breed dogs should include standard mediolateral and craniocaudal projections, a mediolateral projection with the joint maximally extended and the leg supinated 15°, and a craniolateral-to-caudomedial projection.  相似文献   
56.
When external beam radiation therapy is administered to the pelvis, normal tissues irradiated may include the colon, small intestine, urethra, bladder, bone, and spinal cord. The objectives of this retrospective study were to determine the incidence and severity of late radiation effects following pelvic irradiation in dogs and to identify factors that increase the risk of these effects. Medical records of all dogs treated with curative intent external beam radiation therapy to the pelvic region between 1993 and 1999 were reviewed. Patients with follow-up longer than 9 months or any patient that developed late complications earlier than 9 months were evaluated. Sixteen dogs met criteria for inclusion in this study. All dogs were treated with a 6-MV linear accelerator with bilaterally opposed beams. Diseases treated included transitional cell carcinoma of the bladder, transitional cell carcinoma of the prostate, and anal sac apocrine gland adenocarcinoma. Four dose/fractionation schemes were used: 49.5 Gy in 3.3 Gy fractions, 54 Gy in 3.0 Gy fractions, 54 Gy in 2.7 Gy fractions, and 18 Gy intraoperative radiation therapy followed by 43 Gy external beam radiation therapy in 2.9 Gy fractions. Implantable chemotherapy in the form of an OPLA-Pt sponge was used in six dogs as a radiation potentiator. Colitis was the major late effect following pelvic irradiation, occurring in nine dogs (56%). Colitis was characterized as mild in three dogs, moderate in one dog, and severe in five dogs. Three of the dogs with severe effects suffered gastrointestinal perforation. All dogs with severe late effects received 3 or 3.3 Gy per fraction, and 80% received radiation potentiators. In the seven dogs that received 2.7 Gy or 2.9 Gy per fraction, late effects were classified as none (n = 5), mild colitis (n = 1), and moderate colitis (n = 1). Radiation therapy can be administered to the pelvic region with a minimal risk of late effects to the colon by giving smaller doses per fraction and avoiding systemic radiation potentiators.  相似文献   
57.
Congenital hyperplastic goiter and cretinism were documented in a 16 month-old male North American black bear (Ursus americanus). The cub was captured at approximately 8 months of age and maintained for an additional 8 months in captivity. Clinical signs included growth retardation, clumsiness, and facial dysmorphism. Hypothyroidism was documented by determining serum triiodothyronine (T3) and thyroxine (T4) levels. Lysosomal storage disease was ruled out by measuring various lysosomal enzyme activities. Serologic, radiographic, computed tomographic, necropsy, and histopathologic findings were consistent with congenital hypothyroidism and cretinism.  相似文献   
58.
59.
Nasal cavity radiographs and CT images from 31 dogs with nasal cavity cancer were compared. All dogs had abnormal clinical signs relating to -nasal cancer and histologic confirmation of malignant nasal cavity neoplasia. No dog had cyto reductive surgery prior to imaging. All radiographic and CT examinations were abnormal. CT was more accurate than radiographs in identifying unilateral versus bilateral nasal cavity disease and tumor extension into adjacent structures such as the cranial cavity, hard palate, and pterygopala-tine fossa. The improved accuracy of CT in these respects was not of benefit in the confirmation of nasal cavity disease because radiographs were abnormal in every instance. However, CT may be useful for more accurate tumor staging, predicting possible treatment-related complications, and planning of surgery and radiation therapy. It was also determined that one dorsally located radiation therapy portal bounded laterally by the medial ocular canthi, as described in previous reports, would not have been adequate for encompassing all abnormal tissue in 28 of the 31 dogs evaluated.  相似文献   
60.
ULTRASONOGRAPHIC ANATOMY OF THE CANINE BRAIN   总被引:1,自引:0,他引:1  
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