Objective—To describe the pulsed-wave Doppler
tracing of the equine lateral palmar digital artery and
its modification in relation to standardized changes in
Animals—17 healthy Saddlebred horses.
Procedure—Pulsed-wave Doppler examinations of
left and right lateral palmar digital arteries of the horses
were performed. The baseline examination was
performed on each forelimb while horses were standing
squarely with the body weight equally distributed
among the 4 limbs (BED position). For each forelimb,
the examination was repeated during 3 standardized
modifications of the horse's posture (non–weightbearing
[NWB] position, full weight-bearing [FWB]
position, and a position involving hyperextension of
the distal interphalangeal joint [HE position]). In each
position, mean values of systolic peak velocity, first
and second diastolic peak velocity, end-diastolic
velocity, mean velocity, and resistive index were calculated.
Data obtained in each different posture were
Results—No significant differences in blood flow variables
were detected between the left and right forelimbs.
However, significant differences were detected
in values of first diastolic velocity, second diastolic
velocity, mean velocity, and resistive index between
the NWB position and FWB position. Also, end-diastolic
velocity in the NWB position was significantly different
from that recorded in the HE position.
Conclusions and Clinical Relevance—The pulsedwave
Doppler tracing of the equine lateral palmar digital
artery was modified considerably with changes in
posture. This suggests that the use of a precisely standardized
posture for horses is required to obtain repeatable
data. (Am J Vet Res 2004;65:1211–1215)
Objective—To assess the applicability of high-frequency
diagnostic ultrasonography for evaluation and
accurate measurement of the skin thickness of clinically
Animals—26 healthy dogs (12 sexually intact males,
13 sexually intact females, and 1 spayed female) of
various breeds and ages.
Procedure—Ultrasonographic examination of the
skin and histomorphometric analysis of skin biopsy
specimens obtained from the same site were performed.
A 13-MHz linear-array transducer was used to
obtain a series of ultrasonographic images of the skin
in the flank region; images were analyzed and measured
by use of imaging software. Cutaneous biopsy
specimens were placed in fixative and then stained
with H&E and Masson trichrome stains.
Histomorphometric analysis was performed by use of
an image analyzer. Thickness of the epidermis and
dermis of each specimen was evaluated by use of a
semiautomatic procedure of quantification. Data
obtained from ultrasonographic and histologic measurements
were compared by use of the Pearson correlation
Results—The ultrasonographic pattern of canine skin
was consistently characterized by 3 distinct, defined
echogenic layers corresponding to the epidermal
entry echo, epidermis and dermis, and subcutaneous
tissues. A positive correlation was found between
ultrasonographic and histologic measurements of
Conclusions and Clinical Relevance—Comparison
between ultrasonographic and histologic appearance
of the skin revealed that layering of canine skin (ie,
epidermis and dermis) and the subcutaneous tissues
may be recognized and measured by use of high-frequency
ultrasonography. Thus, diagnostic ultrasonography
may be a useful tool for the noninvasive evaluation
of cutaneous disorders in dogs. (Am J Vet Res
Objective—To assess the feasibility and reproducibility of longitudinal tissue Doppler ultrasonographic imaging with regard to determination of velocity, strain, and strain rate (SR) of the left atrium (LA) and use those data to characterize LA synchrony (LAS) for a group of healthy dogs.
Animals—15 healthy dogs.
Procedures—For each dog, apical 4- and 2-chamber echocardiographic views were obtained. Peak velocity, strain, and SR and time to peak value during systole, early diastole, and late diastole were measured for each of the 4 LA walls. To characterize LAS, mean and SD maximal late diastolic time difference (LAD) among the 4 walls were calculated on the basis of time to peak for velocity, strain, and SR; for each, the 95% confidence interval (mean ± 2SD) was calculated. Within-day and between-day intraobserver variability was calculated.
Results—For all dogs, tissue velocity and SR had peak positive values during systole and 2 negative peaks during early and late diastole. Atrial strain had a peak positive value during systole, positive values during early diastole, and a negative peak value during late diastole. Reproducibility was acceptable for most variables. Diastolic strain and SR had the highest variability, but times to peak values were always reproducible. For velocity, strain, and SR, the 95% confidence interval for the maximal LAD was < 50 milliseconds and that for the SD of the LAD was < 23 milliseconds.
Conclusions and Clinical Relevance—Longitudinal tissue Doppler imaging of LA deformation was feasible in healthy dogs, and its application may be useful for understanding atrial pathophysiologic changes associated with various cardiac diseases in dogs.
Procedures—Nonsedated cats were positioned in dorsal and left lateral recumbency to obtain ultrasonographic measurements of the gallbladder via the subcostal and right intercostal acoustic windows, respectively. Gallbladder volume was calculated from linear measurements by use of an ellipsoid formula (volume [mL] = length [mm] × height [mm] × width [mm] × 0.52). Measurements were recorded after food was withheld for 12 hours (0 minutes) and at 5, 15, 30, 45, 60, and 120 minutes after cats were fed 50 g of a standard commercial diet (protein, 44.3%; fat, 30.3%; and carbohydrate, 15.6% [dry matter percentage]).
Results—Agreement between gallbladder linear measurements or GBV obtained from the subcostal and right intercostal windows was good. Feeding resulted in linear decreases in gallbladder linear measurements and GBV. Via the subcostal and intercostal windows, mean ± SD GBV was 2.47 ± 1.16 mL and 2.36 ± 0.96 mL, respectively, at 0 minutes and 0.88 ± 0.13 mL and 0.94 ± 0.25 mL, respectively, at 120 minutes. Gallbladder width most closely reflected postprandial modification of GBV.
Conclusions and Clinical Relevance—Results indicated that ultrasonographic assessment (via the subcostal or right intercostal acoustic window) of postprandial changes in GBV can be used to evaluate gallbladder contractility in cats. These data may help identify cats with abnormal gallbladder emptying.
Objective—To evaluate the diagnostic accuracy of radiographically derived measurements of vertebral heart score (VHS) and sphericity index (SI) in the detection of pericardial effusion (PE) in dogs.
Design—Retrospective case-control study.
Animals—51 dogs with PE associated with various cardiac disorders, 50 dogs with left- or right-sided cardiac disorders without PE, 50 dogs with bilateral cardiac disorders without PE, and 50 healthy dogs.
Procedures—Measurements of VHS on lateral (lateral VHS) and ventrodorsal (ventrodorsal VHS) radiographs, SI on lateral (lateral SI) and ventrodorsal (ventrodorsal SI) radiographs, and global SI (mean of lateral SI and ventrodorsal SI) were obtained. Receiver operating characteristic curves were calculated to evaluate the diagnostic accuracy of the radiographic indexes at differentiating dogs with PE from those with other cardiac disorders without PE.
Results—Measurements of lateral and ventrodorsal VHS were significantly higher in dogs with PE, compared with values for all dogs without PE. Measurements of lateral, ventrodorsal, and global SI were significantly lower in dogs with PE, compared with values for all dogs without PE. Cutoff values of > 11.9, > 12.3, and ≤ 1.17 for lateral VHS, ventrodorsal VHS, and global SI, respectively, were the most accurate radiographic indexes for identifying dogs with PE.
Conclusions and Clinical Relevance—Cardiac silhouettes of dogs with PE were larger and more rounded, compared with those of dogs with other cardiac disorders without PE. Objective radiographic indexes of cardiac size and roundness were only moderately accurate at distinguishing dogs with PE from dogs with other cardiac disorders without PE.
Objective—To assess the usefulness of high-frequency diagnostic ultrasonography for evaluation of changes of skin thickness in relation to hydration status and fluid distribution at various cutaneous sites in dogs.
Animals—10 clinically normal adult dogs (6 males and 4 females) of various breeds.
Procedures—Ultrasonographic examination of the skin was performed before and after hydration via IV administration of an isotonic crystalloid solution (30 mL/kg/h for 30 minutes). A 13-MHz linear-array transducer was used to obtain series of ultrasonographic images at 4 different cutaneous sites (the frontal, sacral, flank, and metatarsal regions). Weight and various clinicopathologic variables (PCV; serum osmolality; and serum total protein, albumin, and sodium concentrations) were determined before and after the infusion. These variables and ultrasonographic measurements of skin thickness before and after hydration were compared.
Results—Among the 10 dogs, mean preinfusion skin thickness ranged from 2,211 μm (metatarsal region) to 3,249 μm (sacral region). Compared with preinfusion values, weight was significantly increased, whereas PCV; serum osmolality; and serum total protein, albumin, and sodium concentrations were significantly decreased after infusion. After infusion, dermal echogenicity decreased and skin thickness increased significantly by 21%, 14%, 15%, and 13% in the frontal, sacral, flank, and metatarsal regions, respectively.
Conclusions and Clinical Relevance—Cutaneous site and hydration were correlated with cutaneous characteristics and skin thickness determined by use of high-frequency ultrasonography in dogs. Thus, diagnostic ultrasonography may be a useful tool for the noninvasive evaluation of skin hydration in healthy dogs and in dogs with skin edema.
Objective—To evaluate radiographic distribution of pulmonary edema (PE) in dogs with mitral regurgitation (MR) and investigate the association between location of radiographic findings and direction of the mitral regurgitant jet (MRJ).
Design—Retrospective case series.
Animals—61 dogs with cardiogenic PE and MR resulting from mitral valve disease (MVD; 51 dogs), dilated cardiomyopathy (9), and hypertrophic cardiomyopathy (1).
Procedures—Thoracic radiographs of dogs with Doppler echocardiographic evidence of MR were reviewed for location (diffuse, perihilar, or focal) of PE. Also, direction (central or eccentric) of the MRJ, as evaluated by Doppler color flow mapping (DCFM), and distribution (symmetric or asymmetric) of radiographic findings were evaluated.
Results—Diffuse, perihilar, and focal increases in pulmonary opacity were observed in 11 (18.0%), 7 (11.5%), and 43 (70.5%) of 61 dogs, respectively. Radiographic evidence of asymmetric PE in a single lung lobe or 2 ipsilateral lobes was found in 21 dogs, with involvement of only the right caudal lung lobe in 17 dogs. Doppler color flow mapping of the MRJ was available for 46 dogs. Of 31 dogs with a central MRJ, 28 had radiographic findings indicative of symmetric PE. Of 15 dogs with eccentric MRJ, 11 had radiographic evidence of asymmetric PE, and all of these dogs had MVD.
Conclusions and Clinical Relevance—In dogs with cardiogenic PE, a symmetric radiographic distribution of increased pulmonary opacity was predominantly associated with a central MRJ, whereas an asymmetric radiographic distribution was usually associated with eccentric MRJ, especially in dogs with MVD.
OBJECTIVE To determine the sensitivity, specificity, and interobserver variability of survey thoracic radiography (STR) for the detection of heart base masses (HBMs) in dogs.
DESIGN Retrospective case-control study.
ANIMALS 30 dogs with an HBM and 120 breed-matched control dogs (60 healthy dogs and 60 dogs with heart disease and no HBM).
PROCEDURES In a blinded manner, 2 observers (designated as A and B) evaluated STR views from each dog for a mass-like opacity cranial to the heart, tracheal deviation, cardiomegaly, findings suggestive of pericardial effusion or right-sided congestive heart failure, and soft tissue opacities suggestive of pulmonary metastases. Investigators subsequently provided a final interpretation of each dog's HBM status (definitely affected, equivocal, or definitely not affected).
RESULTS Considering equivocal interpretation as negative or positive for an HBM, the sensitivity of STR for diagnosis of an HBM was 40.0% (95% confidence interval [CI], 22.5% to 57.5%) and 56.7% (95% CI, 38.9% to 74.4%), respectively, for observer A and 63% (95% CI, 46.1% to 80.6%) and 80.0% (95% CI, 65.7% to 94.3%), respectively, for observer B. The corresponding specificity was 96.7% (95% CI, 93.5% to 99.9%) and 92.5% (95% CI, 87.8% to 97.2%), respectively, for observer A and 99.2% (95% CI, 97.5% to 100%) and 92.5% (95% CI, 87.8% to 97.2%), respectively, for observer B. The presence of a mass-like opacity cranial to the heart or tracheal deviation, or both, was significantly associated with a true diagnosis of HBM.
CONCLUSIONS AND CLINICAL RELEVANCE Results indicated that STR is a highly specific but not a highly sensitive predictor of HBM in dogs.