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991.
Jason T. Crawford DVM Paul A. Manley DVM William M. Adams DVM 《Veterinary radiology & ultrasound》2003,44(6):619-628
Thirteen dogs with fractures requiring surgical repair were evaluated by standard two-view (i.e., lateral and ventrodorsal) radiography, tangential view (ventro 20 degrees cranial-dorsocaudal [inlet] and ventro 20 degrees caudal-dorsocranial [outlet]) radiography, and computed tomography (CT). Radiographic and CT examinations were reviewed independently by the three authors, and specific anatomic sites were graded for the presence or possibility of lesions. The results of radiographic interpretations were compared to CT scan interpretations. Eighty-one percent of skeletal lesions detected by CT scans were diagnosed definitively radiographically. Differences between the interpretation of CT and radiographic examinations included abnormalities associated with soft-tissue structures (P < 0.0001), the sacroiliac joints (P = 0.02), and the acetabula (P = 0.04). Interpretation of the lateral/ventrodorsal and inlet/outlet radiographic series were not statistically different, although inlet views may be complimentary to the standard radiographic examination. Its use deserves further study. Reader variation was less on evaluation of CT examinations than radiographic examinations. CT multiplaner reformations and three-dimensional reconstructions were useful for surgical planning in seven dogs. CT scanning is superior to survey radiography in assessing skeletal and soft-tissue injuries in dogs with pelvic trauma, although all clinically significant surgical lesions were described accurately radiographically. Based on this small series, the routine CT examination of dogs with pelvic trauma may not be justifiable for diagnosis but may be advantageous for surgical planning, especially if acetabular fractures are suspected on radiographs. 相似文献
992.
Erik R. Wisner D V M Dominique Penninck DVM David S. Biller DVM Edward C. Feldman DVM Christiana Drake PhD Thomas G. Nyland DVM 《Veterinary radiology & ultrasound》1997,38(6):462-466
The purpose of this study was to assess the diagnostic utility of parathyroid ultrasonography to differentiate causes of hypercalcemia in dogs. We analyzed qualitative and quantitative ultrasound imaging findings and clinical pathology data from 33 dogs that underwent parathyroid ultrasound examination as part of the diagnostic evaluation for hypercalcemia. Diagnoses of the diseases causing hypercalcemia included parathyroid carcinoma (n = S), parathyroid adenoma (n = 15), parathyroid adenomatous hyperplasia (n = 6), chronic renal insufficiency (n = 3), and hypercalcemia of malignancy (n = 4). All parathyroid lesions were round or oval and hypoechoic compared with surrounding thyroid parenchyma. Adenomatous and adenocarcinomatous glands were 4 mm or larger in longest linear measurement on US examination and were statistically significantly larger than hyperplastic glands. (p < 0.001) Linear measurements of parathyroid glands acquired at the time of ultrasound examination correlated well with direct siz determination after surgical excision. (r2 = 0.9, p < 0.0001) Parathyroid lesions <4 mm are highly suspicious for parathyroid adenoma or carcinoma, while US lesions <4 mm most likely represent primary adenomatous hyperplasia or secondary parathyroid hyperplasia. Parathyroid size estimation from ultrasound examination is an accurate predictor of true size. 相似文献
993.
A. Anastasiou MSc E. Skioldebrand DVM S. Ekman DVM PHD L.D. Hall PHD 《Veterinary radiology & ultrasound》2003,44(5):501-512
The distal row of carpal bones (C2, C3, and C4) from eight left intercarpal joints--four from Standardbred Trotters and four from Swedish Warmblood horses--were used to assess the potential of magnetic resonance (MR) imaging to detect cartilage and bone lesions. The joints used in the study were classified by macroscopic and radiographic examinations as having normal, mild, moderate, or severe articular cartilage lesions and bone sclerosis. Those classifications correlated well with the appearance of the MR images. Bone sclerosis in the MR images was observed as regions of decreased signal intensity. Upon quantitative analysis of the MR images there was a significant difference (p < 0.0001) in the MR signal intensity from areas where radiographic bone sclerosis was observed compared to areas of radiographic nonsclerotic bone. In addition, the MR images were used to pilot the location of histology slices through areas of interest that were then examined microscopically; hence, the lesions found from the MR imaging examination were verified microscopically. It was concluded that cartilage lesions and cartilage loss are related to the sclerotic state of the underlying bone. The MR protocols developed in this study were applied on five intact cadaveric carpal joints, and it was concluded that MR imaging could successfully be used in the intact joint to detect minor cartilage and bone lesions not visualized by either radiography or macroscopic examination. Hence, MR imaging can be used to delineate interactions between articular cartilage and subchondral bone over time and in vivo. 相似文献
994.
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996.
Faith E. Hughes DVM H. David Moll DVM MS Diplomate ACVS Donnie E. Slone DVM MS Diplomate ACVS 《Journal of Equine Veterinary Science》1996,16(4):172-175
Meconium impactions are only rarely refractory to medical therapy. The purpose of this paper is to examine the outcome of 8 foals that required an exploratory celiotomy to correct a meconium impaction. Between 1984 and 1992, 24 foals were referred with a primary diagnosis of meconium impaction. All foals were treated medically prior to and following referral. Of the 24 foals, 8 had impactions requiring surgical intervention. Exploratory celiotomies were performed, and the impaction was reduced manually or by enterotomy. Follow up information was available on 7 foals. All survived surgery and were discharged. Four of the 8 foals matured and raced. Two foals were euthanatized due to extensive serosal adhesions and one foal was euthanatized due to an unrelated orthopedic condition. Our results support the decision for an exploratory surgery only after aggressive medical therapy has failed. Several treatment options have been developed in recent years that have reduced the number of foals that may require surgery. 相似文献
997.
John T. Hathcock DVM MS D. G. Pugh DVM MS Robert E. Cartee DVM MS Linda Hammond DVM 《Veterinary radiology & ultrasound》1995,36(4):290-296
Computed tomography was performed on the head of 6 normal adult llamas. The animals were under general anesthesia and positioned in dorsal recumbency on the scanning table. The area scanned was from the external occipital protuberance to the rostral portion of the nasal passage, and the images are presented in both a bone window and a soft tissue window to allow evaluation and identification of the anatomy of the head. Computed tomography of the llama head can be accomplished by most computed tomography scanners utilizing a technique similar to that used in small animals with minor modification of the scanning table. 相似文献
998.
Computed tomography of the lumbosacral spine was performed on 22 purpose-bred, medium-sized hound dogs between 1 and 6 years of age. Images were evaluated to determine the degree of disc bulge. All dogs were neurologically normal. Dogs were imaged in dorsal recumbency with the pelvic limbs variably extended. Sagittal reconstructions were made from transverse images. The mean (+/-SD) width of the mid-portion of the L7-S1 intervertebral disc was 0.5 +/- 0.07 cm (range 0.33-0.62 cm). All L7-S1 intervertebral discs were dorsally convex, with the mean bulge measuring 0.25 +/- 0.07 cm (range 0.17-0.50 cm). The height of the vertebral canal at L7-S1 was 0.91 +/- 0.11 cm (range 0.68-1.15 cm). The mean percentage of the vertebral canal occupied by the bulge was 26.89 +/- 5.05% (range 20.74-43.08%). Mild bulging of the L7-S1 intervertebral disc can be present without associated neuropathy in medium-sized dogs. 相似文献
999.
David R. Proulx DVM David M. Ruslander DVM Richard K. Dodge MS Marlene L. Hauck DVM PHD Laurel E. Williams DVM Birgitte Horn BVSc G. Sylvester Price DVM PHD Donald E. Thrall DVM PHD 《Veterinary radiology & ultrasound》2003,44(3):352-359
Despite the early notion that canine oral malignant melanoma is radioresistant, recent data suggest that external beam radiotherapy is effective in local tumor control. However, optimal fractionation schedules have not been established. The high rate of regional and distant metastasis is another problem that has hindered long-term control. The role of chemotherapy in the management of canine oral melanoma has also not been determined. In this study, data from 140 dogs irradiated at North Carolina State University were evaluated with the following objectives: (1) to compare the efficacy of three radiation therapy protocols (36 Gy, 9 Gy x 4 fractions; 30 Gy, 10 Gy x 3 fractions; or >45 Gy, 2-4 Gy x 12-19 fractions) for the treatment of dogs with oral malignant melanoma, (2) to identify any host or tumor factors influencing prognosis, and (3) to determine the impact of systemic chemotherapy on treatment outcome. Information regarding response to therapy, disease progression, and survival were determined from the medical records or from information obtained by telephone or mail survey. Relationships between host, tumor, and treatment variables and outcome measures (response, time to first event, and survival) were evaluated using Fisher's exact test (response) and the Cox regression model (time to first event and survival). The median time to first event for the 140 dogs was 5.0 months (95% C.I., 4-6 months) and the median survival was 7.0 months (95% C.I., 6-9 months). In the univariate analysis, the following variables were associated with increased time to first event and survival: (1) rostral tumor sublocation; (2) lack of bone lysis observed on skull imaging, and (3) microscopic tumor burden. In a multivariate analysis of 111 dogs with complete data for these variables, tumor sublocation, bone lysis, and tumor volume were identified as joint predictors of time to first event (p < .001, p < .001, and p = .04, respectively) and survival (p < .001, p < .001, and p = .05, respectively). There were no differences in response, time to first event and survival between the three radiation therapy protocols used. Systemic chemotherapy had no impact on the development of metastatic disease, time to first event, or survival, although the dosages used in this study were suboptimal. External beam radiation therapy is effective in local disease control of canine oral malignant melanoma; however, the optimal fractionation scheme has yet to be determined. The high metastatic rate observed with this disease and the inefficacy of systemic chemotherapy indicate that further investigation into novel therapies is warranted. 相似文献
1000.