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 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 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.
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)
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.