AAFP Abstracts

Abstract 1:
Vet Radiol Ultrasound. 2005 May-Jun;46(3):243-50.

Contrast-enhanced ultrasonography in normal canine liver. Evaluation of imaging and safety parameters.

Nyman HT, Kristensen AT, Kjelgaard-Hansen M, McEvoy FJ.

Department of Small Animal Clinical Sciences, The Royal Veterinary and Agricultural University, Copenhagen, Denmark. hny@kvl.dk

Contrast-enhanced ultrasonography, a new imaging modality in veterinary medicine, can provide data on tissue perfusion. The objective of this study was to use the ultrasonographic contrast agent SonoVue to evaluate various transit time indices in the normal canine liver, to examine the effect of anesthesia on these parameters, and to evaluate the safety of this agent in dogs. The liver of 11 healthy dogs was studied by ultrasound during an intravenous bolus injection of SonoVue. Each dog underwent the examination twice, first with and later without the use of anesthesia. A time-intensity curve was generated from a selected region of interest within the liver from each scanning session. Ratios derived from peak enhancement, time to peak enhancement, up-slope and full-width half-maximum (FWHM) of the curve were calculated from the time-intensity curves, and are reported. There were no statistically significant differences (P > 0.05) in peak enhancement, up-slope and FWHM between dogs that were anesthetized and dogs that were not. Time to peak enhancement, however, was significantly shorter when the dogs were anesthetized than when they were nonanesthetized (P < 0.05). There were no biologically significant changes in clinical laboratory findings. This study indicates that contrast-enhanced ultrasound using SonoVue gives reproducible liver perfusion data, and appears to be a safe and well-tolerated agent for use in dogs. When considering normal values, the use of anesthetic drugs has to be considered.

Abstract 2:
Veterinary Radiology & Ultrasound
Volume 46 Issue 5 Page 411 - September 2005

CHARACTERIZATION OF LYMPHOMATOUS LYMPH NODES IN DOGS USING CONTRAST HARMONIC AND POWER DOPPLER ULTRASOUND
Rochelle M. Salwei1, Robert T. O'Brien1, Jodi S. Matheson1

Doppler ultrasound has been used in humans to determine angioarchitecture of lymph nodes as the criterion for the determination of malignancy. We hypothesized that the vascular and perfusion patterns of a canine malignant lymph node could be characterized with intravenous microbubble ultrasound contrast media and that contrast harmonic ultrasound could provide better conspicuity of the angioarchitecture when compared with Power Doppler ultrasound. In this study, 11 peripheral lymph nodes in dogs with histologically verified malignant lymphoma were imaged with fundamental ultrasound, Power Doppler ultrasound, and three contrast harmonic pulse sequences to characterize the vascular pattern and perfusion. Vascular imaging was greatly enhanced in these nodes with 2.13 times more vessels seen with contrast harmonic ultrasound compared with Power Doppler ultrasound (P<0.01). The angioarchitecture of lymphomatous lymph nodes of dogs in this study were similar to those previously described in malignant superficial lymph nodes in human patients; 45.5% of the nodes had displacement of the central hilar vessel, 45.5% had aberrant vessels, 63.6% had pericapsular vessels, 36.4% had subcapsular vessels, and 81.8% had loss of the central hyperechoic band in fundamental sonography. Poor perfusion, indicated by a lower mean pixel intensity increase between pre- and postcontrast administration images, was seen in 36.4% of the lymph nodes while 63.6% had fair to good perfusion. The perfusion patterns in nine of the 11 lymph nodes were homogenous and two showed focal hypoperfused regions. We conclude that Power Doppler and contrast harmonic ultrasound are beneficial in accurately depicting angioarchitechture and can provide additional information in determining the presence of malignant vascular characteristics within lymphomatous nodes in dogs.

Abstract 3:
Veterinary Radiology & Ultrasound
Volume 46 Issue 5 Page 404 - September 2005

CHARACTERIZATION OF NORMAL AND ABNORMAL CANINE SUPERFICIAL LYMPH NODES USING GRAY-SCALE B-MODE, COLOR FLOW MAPPING, POWER, AND SPECTRAL DOPPLER ULTRASONOGRAPHY: A MULTIVARIATE STUDY
Helena T. Nyman1, Annemarie T. Kristensen1, Ib M. Skovgaard2 and Fintan J. McEvoy1

The objective of this study was to characterize the ultrasonographic patterns of normal superficial lymph nodes and to evaluate whether ultrasonography can help discriminate between different lymphadenopathies (reactive, lymphoma, and metastases) in dogs. Three hundred and eighteen superficial lymph nodes in 142 dogs were studied by B-mode, color flow mapping, power, and spectral Doppler ultrasonography. Size, echogenicity, nodal border definition, presence of a nodal hilus, acoustic enhancement and distribution of vascular flow, as well as perfusion indices were measured. Multivariate statistics using discriminant analysis was used to determine which parameters can be used to predict the diagnosis of the lymph node. The size of the lymph node, distribution of vascular flow within the lymph node, and pulsatility index (PI) in combination gave a classification error of 23% for the four groups of lymph nodes. This was improved to 11% if the nodes were divided into two groups: benign and malignant. There was a significant difference in resistive index (RI) and PI between benign and malignant nodes. Cut-off values were determined using receiver operator curves, 0.68 RI and 1.49 PI.

COMPARISON OF GLOMERULAR NUMBER AND SPECIMEN LENGTH OBTAINED FROM 100 DOGS VIA PERCUTANEOUS ECHO-ASSISTED RENAL BIOPSY USING TWO DIFFERENT NEEDLES
Andrea Zatelli1, Paola D'Ippolito1 and Eric Zini2

Our objective was to evaluate possible differences in the number of glomeruli and length of renal biopsies collected in canine subjects by two different types of biopsy needles: a semiautomatic 18-gauge Trucut and an automated 18-gauge Jamshidi modified (Biopince). One hundred biopsy samples obtained from dogs of different ages and gender affected by different nephropathies were evaluated retrospectively. All animals were biopsied using one of the two different needles. Biopsies were performed under ultrasound guidance and evaluated by a single pathologist. Statistical analysis was performed to evaluate possible differences in the number of glomeruli and length of renal biopsies collected comparisons were determined between subgroups of dogs with or without the identification of renal interstitial infiltrates and/or fibrosis. Neither the mean difference of the number of glomeruli nor the length of tissue sample collected with the different needles was significantly different. Likewise, the average biopsy length did not differ in dogs with or without renal interstitial infiltrate in animals biopsied with either biopsy needle. Both the Biopince and the Trucut devices provide diagnostically adequate biopsy renal specimens using ultrasound-guidance.

Veterinary Radiology & Ultrasound
Volume 46 Issue 3 Page 238 - May 2005

AGE-RELATED CHANGES IN THE ULTRASOUND APPEARANCE OF THE NORMAL FELINE PANCREAS
Martha Moon Larson1, David L. Panciera1, Daniel L. Ward2, Jörg M. Steiner3, David A. Williams3

In humans, pancreatic hyperechogenicity and duct dilation are reported as normal aging changes. Similar changes have been reported with pancreatitis in the cat. We attempted to determine if aging changes occur in the ultrasound appearance of the normal feline pancreas. The pancreas of 84 normal (based on history, physical exam, biochemical profile, and feline trypsin-like immunoreactivity and pancreatic lipase immunoreactivity concentrations) cats of varying ages was scanned. Pancreatic width at the left limb and body, pancreatic duct diameter at left limb and body, and pancreatic echogenicity compared with liver and surrounding fat were noted and compared with age and body weight. Lower and upper limits of the 95% reference intervals for pancreatic left limb width were 2.6 and 9.5 mm, and 3.5 and 8.5 mm for the pancreatic body width. There was no significant difference in pancreatic width between the left limb and body. Lower and upper limits of the 95% reference interval for the diameter of the pancreatic duct at the left limb and body were similar, and were 0.65 and 2.5 mm. There was a weak but significant linear correlation between pancreatic duct diameter and age, with increasing pancreatic duct diameter with increasing age. There was no correlation of pancreatic width with age, and no correlation of pancreatic echogenicity with age or body weight. Based on this study, feline pancreatic size and echogenicity do not change with age. Pancreatic duct diameter increases slightly with age and should not be used as a sole indicator of pancreatitis in the geriatric cat.

News

Meeting:
See you in Jackson Hole, WY for the 2012 Annual Meeting, October 9-13, 2012.
Meeting information and early registration are available now!

Certificate:
Drs. Bossung, Lindquist and Miller have successfully completed the IVUSS Ultrasound Certificate Program, which includes didactic training, case submission, practical exam and a written final examination.

Congratulations Amy, Eric and Chris!