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in Journal of the American Veterinary Medical Association
in Journal of the American Veterinary Medical Association
in Journal of the American Veterinary Medical Association
in Journal of the American Veterinary Medical Association
in Journal of the American Veterinary Medical Association

Abstract

Objective—To investigate contrast-enhanced ultrasonography as a minimally invasive method for the subjective and quantitative assessment of pancreatic and duodenal perfusion in healthy adult dogs, with reference to perfusion in adjacent liver tissue.

Animals—8 clinically normal adult dogs.

Procedures—Contrast-enhanced ultrasonograms of the right pancreatic limb, proximal portion of the descending duodenum, and adjacent liver were acquired after IV administration of a microbubble contrast medium. Following subjective evaluation, quantitative time-intensity curves were generated from regions of interest in the pancreas, duodenum, and liver. Five contrast medium characteristics representing perfusion parameters were determined for each organ and used for statistical analysis: interval to arrival, inflow rate, peak intensity (PI), time of peak intensity (TPI), and outflow rate.

Results—Significant associations between pancreatic and duodenal values were found for interval to contrast medium arrival, PI, TPI, and outflow rate. Pancreatic and duodenal inflow rates were not correlated. Inflow and outflow rates were significantly faster and TPI significantly shorter for the pancreas and duodenum, compared with values for the liver. There was no significant difference among all 3 organs for interval to arrival and PI of contrast medium. Subjective evaluation findings corresponded to quantitative analysis results.

Conclusions and Clinical Relevance—Results suggested that contrast-enhanced ultrasonography may be a useful, minimally invasive method for evaluating pancreatic and duodenal perfusion in dogs. The data from healthy dogs reported here could aid in the assessment of pancreatic and duodenal conditions and their response to medical treatment.

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in American Journal of Veterinary Research

Abstract

Objective—To determine the ultrasonographic appearance and detectability of edema induced by SC injection of mild silver protein suspension in the mammary gland attachments of dairy cows.

Design—Prospective study.

Animals—6 lactating cows.

Procedure—In each cow, the number of quarters that received injections was randomly assigned. A mild silver protein susoension was injected SC into cranial and caudal mammary gland attachment sites. The number of injections and volume injected were determined on the basis of the appearance of the mammary gland and the desired subjective visual effect. Seventeen sites were chosen for injection and 7 sites did not receive injections. Ultrasonographic images were obtained 1 day prior and 6 days after injections were started. Cows received injections 1, 3, and 5 days after initial sonography. The sonographer was unaware of which sites received injections.

Results—Ultrasonography revealed alternating hypoechoic and hyperechoic bands at injection sites. Certain injections caused the intimal surface of the subcutaneous abdominal vein to develop a corrugated appearance. All injection sites were correctly identified ultrasonographically (100% sensitivity, 100% specificity) with a positive and negative predictive value of 1.0.

Conclusions and Clinical Relevance—Results suggest that mild silver protein suspension injected SC to enhance the appearance of the mammary glands of dairy cows can be readily detected by ultrasonography. Detection of injection sites should be made on the basis of the distribution and ultrasonographic appearance of edema. (J Am Vet Med Assoc 2002;221:408–410)

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in Journal of the American Veterinary Medical Association

Objective

To determine whether exogenous isobutane gas infused into the udders of dairy cattle could be detected ultrasonographically, and if so, what effects volume of gas infused and infusion pressure had on how long after infusion exogenous isobutane gas could be detected.

Design

Randomized block design.

Animals

8 Holstein cows 28 to 32 days after parturition.

Procedure

In each cow, 1 mammary gland was not treated and the other 3 received 1 of 3 treatments by means of intramammary infusion: low volume-high pressure, low volume-low pressure, and high volume-high pressure infusion of isobutane gas. Mammary glands were examined ultrasonographically 1 hour before and 1,3, 12, 24, 36, 48, 72, and 96 hours after treatment.

Results

After intramammary infusion of isobutane gas, bright echoes and associated acoustic shadows were seen ultrasonographically; echoes were no longer seen 72 hours after gas infusion. Percentages of mammary glands in which bright echoes were detected were not significantly different among the 3 treatment groups at any time during the study.

Conclusions and Clinical Relevance

Results suggest that exogenous isobutane gas infused into the mammary glands to enhance the appearance of the udder of show dairy cattle can be readily detected by ultrasonography. (J Am Vet Med Assoc 1999;215:366–368)

Free access
in Journal of the American Veterinary Medical Association

Abstract

Objective

To determine the usefulness of a new method of measuring acoustic backscatter and attenuation in the liver of dogs with experimental steroid-induced hepatopathy.

Animals

10 clinically normal dogs.

Procedure

Steroid hepatopathy was induced by daily injections of prednisone (2 mg/kg of body weight, IM). Dogs were evaluated histologically and were sonographically imaged on days 0, 3, 7, 10, and 14. Acoustic backscatter and attenuation were measured from in vivo images of dogs, using a video signal method, and compared with results obtained from analysis of the unprocessed radio frequency signal.

Results

Histologic evaluation revealed midzonal, predominantly water-filled vacuoles in hepatocytes by day 7, which persisted for the remainder of the study and significantly (P = 0.0001) increased liver weight on day 14. Attenuation and backscatter increased during the experimental period. Mean effective attenuation difference was higher (P = 0.015) in the liver imaged through a left paraxyphoid window in experimental dogs by day 3. Significantly (P < 0.05) greater attenuation persisted in the liver of experimental dogs throughout the experimental period. Mean backscatter ratio was significantly increased (P = 0.02) by day 10. Uncorrected pixel intensity of the liver in 2 experimental dogs was approximately equal to that of the spleen on day 10 and greater than that of the spleen on day 14.

Conclusion

Administration of prednisone to dogs results in increased acoustic backscatter and attenuation in the liver.

Clinical Relevance

The video signal method is a sensitive technique for detecting subtle acoustic changes in the liver of dogs. (Am J Vet Res 1996;57:1690–1694)

Free access
in American Journal of Veterinary Research

Abstract

Objective—To evaluate perfusion of abdominal organs in healthy cats by use of contrastenhanced ultrasonography.

Animals—10 young healthy anesthetized cats.

Procedures—Contrast-enhanced ultrasonography of the liver, left kidney, pancreas, small intestine, and mesenteric lymph nodes was performed on anesthetized cats.

Results—Typical perfusion patterns were found for each of the studied organs. Differences in perfusion among organs were associated with specific physiologic features. The liver was enhanced gradually and had a more heterogeneous perfusion pattern because of its dual blood supply and close proximity to the diaphragm, compared with other organs. An obvious and significant difference in perfusion was detected between the renal cortex and medulla. No significant differences in perfusion were detected among the pancreas, small intestine, and mesenteric lymph nodes.

Conclusions and Clinical Relevance—Results indicated that contrast-enhanced ultrasonography can be used in cats to estimate organ perfusion as in other species. Observed differences in perfusion variables can be mostly explained by physiologic differences in vascularity. (Am J Vet Res 2010;71:1305–1311)

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in American Journal of Veterinary Research