Search Results

You are looking at 1 - 10 of 12 items for

  • Author or Editor: Phillip F Steyn x
  • Refine by Access: All Content x
Clear All Modify Search

Summary:

In this study, we found that the rate at which radiographically diagnosed simultaneous pleural and peritoneal effusions (double effusions [de]) developed was highest in dogs and cats with infectious causes of pleuritis and/or peritonitis and in those with pancreatitis. However, de were observed more frequently in dogs and cats with neoplastic and cardiovascular diseases. Nonneoplastic liver disease was also documented as a cause of de in the population of this study. Frequency of de was increased in males and in animals > 6 years old. The finding of simultaneous pleural and peritoneal effusions can be considered an indicator of disease severity, and warrants a poor to grave prognosis.

Free access
in Journal of the American Veterinary Medical Association

Summary

The biological half-life (TB) of aerosolized 99mTc-diethylenetriaminepentaacetate was determined in 14 lung regions of 18 clinically normal Beagles. Three groups of lung regions or volumes were identified on the basis of significantly (P < 0.05) different TB. Group A (mean ± SD TB, 82 ± 21 minutes) included the transversely oriented cranial and caudal nonperihilar regions. Group B (mean ± SD, 61 ± 15 minutes) represented all sagittally oriented lung regions and the entire lung field. Group C (mean ± SD, 49 ± 11 minutes) included the transversely oriented cranial and caudal perihilar regions. Clearance of 99mTc-diethylenetriaminepentaacetate is considered a function of transepithelial transport into the blood, as well as bronchial transport via the mucociliary transport mechanism.

Free access
in American Journal of Veterinary Research

Abstract

Objective—To determine the effect of a static magnetic field on relative blood flow to the metacarpus of horses.

Design—Randomized controlled clinical trial.

Animals—6 healthy adult horses.

Procedure—Red blood cells were radiolabeled in vivo by administration of technetium Tc 99m (pyro- and trimeta-) phosphates, and scintigraphic images were obtained 30 minutes later. A magnetic wrap that emitted a static magnetic field was applied to 1 metacarpus and a control wrap was applied to the contralateral metacarpus. Forty-eight hours later, the wraps were removed, and scintigraphy was repeated. Relative perfusion ratios were calculated by dividing mean count per pixel for the portion of the metacarpus under the wrap by mean count per pixel for a portion of the distal aspect of the antebrachium that was not in the magnetic field.

Results—The difference between the relative perfusion ratio prior to application of the wrap and the ratio after application of the wrap for limbs that received the magnetic wrap was not significantly different from the difference in ratio for limbs that received the control wrap.

Conclusions and Clinical Relevance—Results suggest that in horses, the static magnetic field associated with application of commercially available magnetic wraps for 48 hours does not increase blood flow to the portion of the metacarpus underneath the wrap.(J Am Vet Med Assoc 2000;217:874–877)

Full access
in Journal of the American Veterinary Medical Association

  • Colonic adenocarcinoma is a rare tumor of glandular crypt epithelium in middle-aged and older horses; the tumor may metastasize to the mesenteric lymph nodes, liver, and lungs, but it has not been reported to metastasize to bone and muscle.

  • Clinical signs of abdominal neoplasia may be vague and nonspecific; extensive diagnostic testing of these animals often is required.

  • Radionucleotide imaging, using technetium Tc 99m hydroxymethylene diphosphate in conjunction with technetium Tc 99m hexamethylpropylenamine oxime, can be a sensitive noninvasive tool to identify the nature of a disseminated disease when radiography is not sensitive enough to detect early osteoblastic changes that precede morphologic changes.

Free access
in Journal of the American Veterinary Medical Association

Abstract

Objective—To evaluate use of technetium Tc 99m disodium hydroxymethylene diphosphonate (99m-Tc- HDP) for assessing fracture healing and 99m-Tc-HDP and technetium Tc 99m ciprofloxacin (99m-Tc-CIPRO) for early diagnosis of osteomyelitis in rabbits.

Animals—32 skeletally mature New Zealand White rabbits.

Procedure—A femoral fracture defect stabilized with bone plates and cortical screws was used. Scintigraphy was performed 4, 8, 12, and 16 weeks after surgery. The 99m-Tc-CIPRO scan was performed 48 hours after the 99m-Tc-HDP scan. The uptake ratio of the experimental limb to the normal limb was calculated by use of multiple regions of interest. Results of radiography performed to determine external callus and lysis grade and percentage defect ossification at 16 weeks were compared with scintigraphy results.

Results—Infected fractures had a higher uptake ratio for 99m-Tc-HDP and 99m-Tc-CIPRO than noninfected fractures. Infected fractures could be differentiated from noninfected fractures late in healing by use of 99m-Tc-HDP. Although 99m-Tc-CIPRO was better than 99m-Tc-HDP for identifying infection, there was a high incidence of false positive and negative results with 99m-Tc-CIPRO. There was an association between 99m-Tc-HDP uptake ratio and callus formation and a good correlation between 99m-Tc-HDP uptake ratio and defect ossification after 4 weeks.

Conclusions and Clinical Relevance—99m-Tc-HDP and 99m-Tc-CIPRO may be useful for diagnosing osteomyelitis late in fracture healing; however, false positive and false negative results occur. Technetium Tc 99m disodium hydroxymethylene diphosphonate may be useful for evaluating fracture healing. ( Am J Vet Res 2003;64:736–745)

Full access
in American Journal of Veterinary Research

Objective

To compare iridocorneal angle grading systems on the basis of gonioscopy and ultrasound biomicroscopy (UBM).

Design

Original cross-sectional observational study.

Animals

22 dogs.

Procedure

Gonioscopy, goniophotography, and UBM were performed on 38 eyes from dogs without clinical evidence of glaucoma in the eyes examined.

Results

Predominant gonioscopic grades derived from goniophotographs were considered normal (n = 26) and mild (12). Ultrasound biomicroscopy angle measurements ranged from 16 to 38° (mean ± SD, 26.2 ± 4.5°). Ciliary clefts depicted on UBM images were graded as open (n = 4), compact/narrow (23), and closed (11). Significant differences were not found between UBM-derived ciliary cleft grades and goniophotography-derived dysgenesis grades, nor between UBM-derived ciliary cleft grades and subjective gonioscopic grades.

Clinical Implications

Because gonioscopy allows evaluation of the anterior face of the ciliary cleft, whereas UBM provides cross-sectional information of the iridocorneal filtration angle, UBM may yield more information regarding pathogenesis and prognosis of, and preferred management approaches to, glaucoma. Ultrasound biomicroscopy may also be useful as a predictor of glaucoma or to diagnose early stages of glaucoma. (J Am Vet Med Assoc 1998;213:635-638)

Free access
in Journal of the American Veterinary Medical Association

Summary

Thirty cubital joints from 16 dogs suspected of having a fragmented medial coronoid process were examined. Four breeds accounted for 87.5% of the cases: German Shepherd Dog (25%), Labrador Retriever (25%), Rottweiler (18.75%), and Golden Retriever (18.75%). Seventy-five percent of the dogs were male. Mean age of affected dogs was 13.6 months. Plain-film radiography, xeroradiography, linear tomography, arthrography, and computed tomography were performed on each cubital joint prior to surgical exploration of the joint. Three reviewers evaluated each diagnostic study and independently determined whether a fragment from the medial coronoid process could be seen. The consensus opinion was compared with the finding at surgery. Abnormalities of the medial coronoid process were detected in 25 of 30 joints at surgery. Fragmented coronoid process was found in 17 of 30 joints, and wear lesions were observed in 8 of 30 joints. Computed tomography had the highest accuracy (86.7%), sensitivity (88.2%), and negative-predictive value (84.6%) of the 5 imaging modalities evaluated (P < 0.05). Specificity and positive-predictive value of all imaging techniques were high. There was no significant difference between the diagnostic ability of plain-film radiography, xeroradiography, or linear tomography of the cubital joint. The combination of plain-film radiography and linear tomography provided an improvement in accuracy, approaching that of computed tomography.

Free access
in Journal of the American Veterinary Medical Association

Summary

A technique for arthrography of the cubital joint in clinically normal large-breed dogs was developed with the objective of improving visualization of the articular margin of the medial coronoid process. A lateral approach to the cubital joint for injection of contrast medium was selected. Arthrography of 24 cubital joints was performed by using 14 dogs. Twelve combinations of iodinated contrast medium, consisting of various concentrations (3) and volumes (4), were used. Two sets of arthrograms for each of the 12 combinations of contrast medium were obtained. Five radiographic views were used for each set.

All arthrograms were examined by 3 evaluators, and each articular surface received a numerical rating for how well it could be seen in each view. Results of the evaluation indicated that low volumes of contrast medium were preferable to high volumes, with 2 ml providing the best visualization. Concentration of iodine seemed less important than did volume.

The numerical ratings also indicated that the articular margin of the coronoid process was clearly observed a maximum of only 24% of the time on a slightly supinated mediolateral projection. The articular margins of the head of the radius, trochlea humeri, and trochlear notch were well visualized > 90% of the time.

Arthrography of the cubital joint was technically easy to perform, and complications were not encountered, but arthrographic anatomy of the cubital joint is complex. Potential uses for arthrography of the cubital joint include diagnosis of osteochondrosis, intraarticular fragments, and joint capsule ruptures.

Free access
in Journal of the American Veterinary Medical Association