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1.
Contrast-enhanced ultrasound is one of method for evaluating renal perfusion. The purpose of this project was to assess perfusion patterns and dynamics in normal micropig kidney using ultrasonographic contrast media. Eight young healthy micropigs were included in this study. Micropigs were anesthetized with propofol and received an intravenous bolus of microbubble contrast media through an ear vein. Time/mean pixel value (MPV) curves were generated for selected regions in the right renal cortex and medulla. The parenchyma was enhanced in two phases. The cortex was first enhanced followed by a more gradual enhancement of the medulla. A significant difference in perfusion was detected between the cortex and medulla. Following the bolus injection, the average upslope was 0.68 ± 0.27 MPV/sec, downslope was -0.27 ± 0.13 MPV/sec, baseline was 73.9 ± 16.5 MPV, peak was 84.6 ± 17.2 MPV, and time-to-peak (from injection) was 17.5 ± 6.6 sec for the cortex. For the medulla, the average upslope was 0.50 ± 0.24 MPV/sec, downslope was -0.12 ± 0.06 MPV/sec, baseline was 52.7 ± 7.0 MPV, peak was 65.2 ± 9.3 MPV, and time-to-peak (from injection) was 27.5 ± 5.0 sec. These data can be used as normal reference values for studying young micropigs.  相似文献   

2.
Eight adult dogs with no evidence of liver disease, weighing between 8 and 25 kg were imaged after injection of a microbubble contrast medium using harmonic ultrasound imaging. All dogs received three separate bolus contrast injections, and six dogs also received three separate constant rate infusions each. Time/Mean Pixel Value curves were generated for selected regions of the liver. Upslope, downslope, baseline, peak, change, and time to peak were calculated. For bolus injection (averaging all subjects), upslope was 3.85 +/- 1.50 Mean Pixel Values/s, downslope was -0.71 +/- 0.30 Mean Pixel Values/s, baseline was 72.38 +/- 17.82 Mean Pixel Values, peak was 120.26 +/- 17.44 Mean Pixel Value, change from baseline to peak was 47.88 +/- 6.92 Mean Pixel Values, time to peak (from injection) was 22.88 +/- 6.79 s, and time to peak (from first upslope) was 13.88 +/- 1.55 s. Data acquisition and analysis from constant rate infusions was more cumbersome than for bolus, and results were less repeatable. There were significant differences (p < .005) in upslope, downslope, peak values, and time to peak between the two methods. These baseline data may prove useful in the evaluation of dogs with diffuse hepatic disease.  相似文献   

3.
Contrast enhanced ultrasound (CEUS) is useful to evaluate tissue perfusion in the kidney. In veterinary medicine, sedation or anesthesia may be required in uncooperative or panting patients. The aim of this study was to evaluate and compare the normal kidney perfusion patterns in conscious and anesthetized dogs using CEUS. Eight healthy beagles were used in this study. Scanning was performed in conscious dogs using manual restraint (conscious group), or under general anesthesia using tiletamine-zolazepam and medetomidine (TZM group) or medetomidine (M group). The contrast agent (Sonovue®) was administered as an IV bolus. The peak intensity (PI), time to peak enhancement from injection (TTP0) and the time to peak enhancement from the initial rise (TTPup), upslope, downslope and area under the curve (AUC) were analyzed. Compared to the cortical values in the conscious group, TTP0 was significantly delayed in the TZM group, and upslope, TTP0 and TTPup were significantly different in the M group. The AUCs in the TZM and M groups were not different from those in the conscious group. The upslope of renal medullary perfusion was significantly decreased in the TZM and M groups. TTP0 and TTPup were also significantly delayed in these groups. The AUC of the medulla was significantly decreased in the M group. Therefore, TZM is useful as an anesthetic protocol when performing CEUS, and the obtained data may serve as reference values in the evaluation of renal perfusion using CEUS in dogs under anesthesia.  相似文献   

4.
Contrast‐enhanced ultrasonography is useful in differentiating adrenal gland adenomas from nonadenomatous lesions in human patients. The purposes of this study were to evaluate the feasibility and to describe contrast‐enhanced ultrasonography of the normal canine adrenal gland. Six healthy female Beagles were injected with an intravenous bolus of a lipid‐shelled contrast agent (SonoVue®). The aorta enhanced immediately followed by the renal artery and then the adrenal gland. Adrenal gland enhancement was uniform, centrifugal, and rapid from the medulla to the cortex. When maximum enhancement was reached, a gradual homogeneous decrease in echogenicity of the adrenal gland began and simultaneously enhancement of the phrenicoabdominal vessels was observed. While enhancement kept decreasing in the adrenal parenchyma, the renal vein, caudal vena cava, and phrenicoabdominal vein were characterized by persistent enhancement until the end of the study. A second contrast enhancement was observed, corresponding to the refilling time. Objective measurements were performed storing the images for off‐line image analysis using Image J (ImageJ©). The shape of the time–intensity curve reflecting adrenal perfusion was similar in all dogs. Ratios of the values of the cortex and the medulla to the values of the renal artery were characterized by significant differences from initial upslope to the peak allowing differentiation between the cortex and the medulla for both adrenal glands only in this time period. Contrast‐enhanced ultrasonography of the adrenal glands is feasible in dogs and the optimal time for adrenal imaging is between 5 and 90 s after injection.  相似文献   

5.
[目的]探讨建立犬药物性急性肾损伤模型。[方法]16只健康成年比格犬每8 h皮下注射20 mg/kg庆大霉素,注射前血肌酐浓度(SCr)作为基线,注射后每6 h采集血液检测SCr浓度,于SCr无明显升高、SCr升高临近正常值上限及SCr升高到基线1.5倍时观察肾组织病理形态学改变,确定犬药物性急性肾损伤模型。[结果]SCr在注射庆大霉素后78 h显著升高(P<0.05),实验犬SCr均在120～132 h达到基线的1.5倍;肾组织在SCr升高到基线1.5倍时肾皮质大面积的肾小管变性、坏死,管腔有较多的细胞碎片和颗粒管型,基底膜裸露明显,髓质损伤较轻;与健康对照组相比,注射后肾损伤评分差异有统计学意义(P<0.05),且肾损伤随用药时间延长评分逐渐增加。[结论]庆大霉素每8 h皮下注射20 mg/kg直至SCr浓度升高到基线1.5倍的方法可成功建立犬药物性急性肾损伤模型。  相似文献   

6.
Contrast‐enhanced ultrasound may be helpful for detecting early renal microvascular damage and dysfunction in dogs. However, before this noninvasive imaging method can be tested as an early‐stage screening tool in clinical patients, an improved understanding of long‐term variation in healthy animals is needed. In this prospective, secondary, longitudinal, serial measurements study, variability of contrast‐enhanced ultrasound renal perfusion parameters was described for eight healthy dogs, using seven time points and a period of 83 weeks. Dogs were sedated with butorphanol (0.4 mg/kg), and contrast‐enhanced ultrasound of each kidney was performed after an intravenous bolus injection of a microbubble contrast agent (0.04 mL/kg). Time‐intensity curves were created from regions‐of‐interest drawn in the renal cortex and medulla. Intensity‐related parameters representing blood volume and time‐related parameters representing blood velocity were determined. A random‐effects model using restricted maximum likelihood was used to estimate variance components. Within‐dog coefficient of variation was defined as the ratio of the standard deviation over the mean. Time‐related parameters such as time‐to‐peak, rise and fall time had lowest within‐dog variability. Intensity‐related parameters such as peak enhancement, wash‐in and wash‐out area under the curve, total area under the curve, and wash‐in and washout rates had high within‐dog variability (coefficient of variation > 45%). Authors therefore recommend the use of time‐related parameters for future studies of renal perfusion. Within‐dog variability for bilateral kidney measurements was extremely low, therefore contrast‐enhanced ultrasound may be particularly useful for detecting unilateral changes in renal perfusion. Future studies are needed to compare contrast‐enhanced ultrasound findings in healthy dogs versus dogs with renal disease.  相似文献   

7.
Contrast‐enhanced ultrasonography provides a more functional diagnostic image than conventional ultrasonography. This prospective exploratory study compared the novel contrast agent, Visphere?, with commercial contrast agents in five healthy Beagle dogs. Visphere? has the smallest diameter and highest concentration compared with Sonazoid® and SonoVue®. Each dog received an intravenous injection of Visphere?, Sonazoid®, or SonoVue®. Images were recorded for 300, 600, and 60 s in the heart, liver, and left kidney, respectively. The mean pixel values of the regions of interest for each organ were expressed as time intensity curves (TIC). The agents all improved the visualization of left ventricular endocardial border delineation in the heart, and had similar TICs and clinical useful durations. In contrast, Visphere? expressed the highest mean pixel value in the liver parenchyma at an early observation time and maintained the intensity until 600 s, like Sonazoid®. The renal evaluation results indicated there were no statistically significant differences in time‐to‐peak for the renal cortex or medulla among the agents. Compared with the other two agents, SonoVue® had the lowest peak enhancement for the renal cortex and medulla. No dogs had any adverse reactions during or after the study. All three agents provided adequate results for left ventricular endocardial border delineation, and Visphere? may have the same potential as Sonazoid® to detect and characterize hepatic lesions. Visphere? and Sonazoid® may offer better visualization quality to evaluate renal function. In conclusion, the novel contrast agent, Visphere?, is comparable with commercial agents and could be applied in different major organs in dogs.  相似文献   

8.
Contrast‐enhanced ultrasound offers a noninvasive means of subjectively and quantitatively evaluating renal perfusion in cats with renal disease, or in renal transplant patients. In this study, we characterized the pattern of ultrasonographic contrast enhancement in 16 normal feline kidneys in eight cats using contrast‐enhanced power Doppler and contrast‐enhanced harmonic ultrasound techniques. Mean time to peak contrast enhancement for the whole kidney was longer using contrast‐enhanced harmonic ultrasound (16.8s, SD 4.7s) than contrast‐enhanced power Doppler ultrasound (12.2s, SD 1.8s). The time to peak enhancement for the cortex alone in contrast‐enhanced harmonic ultrasound was 13s (SD 3.2s), and for the renal medulla was 25.5s (SD 8.7s). The half time for washout of contrast agent was 39s (SD 14.5s) for contrast‐enhanced harmonic ultrasound. The pattern of contrast enhancement in these normal feline kidneys can be used as normal reference values for the evaluation of clinical patients. Contrast‐enhanced harmonic ultrasound may allow the differentiation between cortical and medullary perfusion patterns.  相似文献   

9.
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10.
This study was conducted to measure the concentrations of strontium (Sr), barium (Ba), cadmium (Cd), copper (Cu), zinc (Zn), manganese (Mn), chromium (Cr), antimony (Sb), selenium (Se), and lead (Pb) in canine liver, renal cortex, and renal medulla, and the association of these concentrations with age, gender, and occurrence of chronic kidney disease (CKD). Tissues from 50 dogs were analyzed using inductively coupled plasma mass spectrometry. Cu, Zn, and Mn levels were highest in the liver followed by the renal cortex and renal medulla. The highest Sr, Cd, and Se concentrations were measured in the renal cortex while lower levels were found in the renal medulla and liver. Female dogs had higher tissue concentrations of Sr (liver and renal medulla), Cd (liver), Zn (liver and renal cortex), Cr (liver, renal cortex, and renal medulla), and Pb (liver) than male animals. Except for Mn and Sb, age-dependent variations were observed for all element concentrations in the canine tissues. Hepatic Cd and Cr concentrations were higher in dogs with CKD. In conclusion, the present results provide new knowledge about the storage of specific elements in canine liver and kidneys, and can be considered important reference data for diagnostic methods and further investigations.  相似文献   

11.
To determine the position, dimensions, and structure of the right kidney in cattle by use of ultrasonography, the right kidney of 11 healthy Brown Swiss cows was examined 10 times within 2 weeks. A 3.5- and 5.0-MHz linear and convex transducer was placed on the right side of the cow in the lumbar region, in the paralumbar fossa, and in the last intercostal space. The echogenicity of various renal structures differed. The lobulation of the kidney in cattle could be visualized ultrasonographically; however, the cortex and medulla could not be differentiated. The distance between body surface and the right kidney was almost 3 times larger (5.3 +/- 1.71 cm, mean +/- SD) in the lumbar region than in the paralumbar fossa (1.8 +/- 0.52 cm). The vertical diameter of the kidney was remarkably smaller (5.1 +/- 0.47 cm) than the horizontal diameter (9.4 +/- 0.98 cm). In 7 cows, the thickness of the renal cortex and medulla was between 1.9 and 2.1 cm. The medullary pyramids could be visualized when the transducer was placed in the paralumbar fossa. Fourteen of 19 variables measured had a coefficient of variation between 8 and 14%. It was concluded that the ultrasonographic values determined in this study can be used as references for the diagnosis of morphologic changes in the right kidney of domestic dairy cattle.  相似文献   

12.
The purpose of this study was to describe normal feline hypophyseal mensuration and contrast enhancement characteristics using dynamic computed tomography (CT) imaging. An intravenous bolus of an ionic iodinated contrast medium was administered to eight cats using a pressure injector while dynamic CT images were obtained every 5 s for five cats and every 7 s for three cats for a total imaging time of 5 min. Each pituitary was measured at its maximum height and width on the peak contrast medium enhancement image. A hand-drawn region of interest was placed around each hypophysis cerebri and time attenuation curves were generated. The specific enhancement pattern of the hypophysis cerebri for each cat was recorded. The mean width and height of the hypophysis cerebri was 5.2 +/- 0.4 (average +/- SD) mm and 3.1 +/- 0.3 mm, respectively. The mean time to maximum contrast enhancement was 28.6 +/- 14.8 s (range 14-50 s) from the onset of contrast medium injection. Four cats had initial dorsal and peripheral contrast enhancement patterns of the hypophysis cerebri, while four cats had an initial central contrast medium enhancement pattern. The hypophysis cerebri had a homogenous appearance in all cats, 28-50 s after contrast medium injection. The average (+/- SD) clearance half-time was 292 (+/- 87) s. Normal hypophysis cerebri mensuration and contrast medium enhancement characteristics will help in clinical evaluation of the feline hypophysis cerebri.  相似文献   

13.
OBJECTIVE: To determine clinical status and renal and hematopoietic function after kidney donation and identify risks associated with kidney donation in dogs. DESIGN: Prospective study. ANIMALS: 14 dogs that underwent unilateral nephrectomy for kidney donation. PROCEDURES: Records were reviewed retrospectively to collect data regarding prenephrectomy clinicopathologic variables. Dogs were reexamined prospectively at various times after nephrectomy, and pre- and postnephrectomy CBC, serum biochemical analyses, urinalysis, and urine protein-to-urine creatinine ratio were compared. Six dogs had postnephrectomy renal volume determined ultrasonographically, and 4 of those dogs also underwent scintigraphic determination of glomerular filtration rate and renal biopsy. RESULTS: All dogs were clinically normal at the time of reevaluation. There were no significant differences between prenephrectomy and postnephrectomy values for BUN concentration or urine specific gravity. Mean postnephrectomy serum creatinine concentration was significantly greater than prenephrectomy concentration. Mean serum phosphorus concentration was significantly decreased after nephrectomy, and mean Hct, corpuscular volume, and corpuscular hemoglobin concentration were significantly increased after nephrectomy. Postnephrectomy renal volume was greatest in dogs < 12 months old at the time of surgery. Mean postnephrectomy glomerular filtration rate was 2.82 +/- 1.12 mL/kg/ min (1.28 +/- 0.51 mL/lb/min). Renal biopsy specimens obtained during and after nephrectomy were histologically normal. CONCLUSIONS AND CLINICAL RELEVANCE: Renal and hematopoietic variables were within reference ranges in dogs examined up to 2.5 years after unilateral nephrectomy. Compensatory renal hypertrophy was greatest in dogs < 1 year of age at donation. Donor age, along with histocompatability, may be an important factor in selecting dogs for kidney donation.  相似文献   

14.
Ultrasonography is important in the clinical examination of the foal. The ultrasonographic appearance and size of the neonatal kidneys were defined and an imaging protocol established in 6 normal Thoroughbred foals (mean age +/- s.d. 5.0 +/- 3.2 days). Characteristically, in both the heart-shaped right kidney and bean-shaped left kidney, the renal cortex was more echogenic than the medulla. The terminal recesses, renal crest and pelvis were identified, as was the ureter, which contained anechoic urine in its lumen. The renal, interlobar and arcuate vessels were seen. For the right kidney, the ultrasonographic probe was placed at the 14-17th intercostal spaces and paralumbar fossa. For the left kidney, the probe was at the 16th or 17th intercostal spaces and paralumbar fossa. Perirenal structures, including the caudate lobe of the liver, the dorsal extremity of the spleen, the adrenals, the aorta and caudal vena cava were also identified. An understanding of the ultrasonographic appearance of the normal neonatal kidney, accompanied by a routine imaging protocol to ensure that all regions of each kidney are examined, permit a more informed interpretation of renal images in the first few days postpartum.  相似文献   

15.
Our goal was to investigate the effect of contrast medium injection duration on pulmonary artery peak enhancement and time to peak enhancement. Fourteen dogs were allocated into one of seven predefined weight categories, each category contained two dogs. Dogs in each weight category were assigned to group A or B. Animals in each group received a different contrast medium injection protocol. In group A, a fixed injection rate of 5 ml/s was used. In group B, the contrast injection rate was calculated as follows: flow rate=contrast volume/scan duration+10 s. Time to peak enhancement and peak enhancement of the main left and right pulmonary arteries were measured on single‐level, dynamic CT images for a fixed time of 30 s. Rank correlation (Spearman's) coefficients between injection duration and time to peak enhancement and between body weight and peak enhancement were calculated. For group A, there was a significant negative correlation between peak enhancement and weight (r=?0.94; P=0.005), while for group B, there was no significant correlation (r=?0.64 and P=0.18). There was a significant correlation between time to peak enhancement and injection duration in both groups (group A: r=0.99; P=0.006 and group B: r=0.85; P=0.02). In conclusion, injection duration is a key feature in a CT angiography injection protocol. A protocol with an injection duration adjusted to the scan duration seems to be particularly suitable for veterinary applications where a population with great weight variability is studied.  相似文献   

16.
本试验旨在确定犬肝多期增强扫描造影剂使用剂量、注射速率及最佳延迟时间。选取不同的碘海醇剂量（500、575、650 mg·kg-1,以I含量计）及速率（2、3 mL·s-1）对犬进行造影,动态扫描,计算造影前后主动脉、门静脉、肝实质CT增强值,确定最佳造影剂剂量及注射速率。然后采用最佳造影剂剂量和注射速率对不同体型的犬进行造影,动态扫描后绘制时间-密度曲线,统计主动脉、门静脉、肝实质的达峰时间,计算达峰时间和注射时间的差值（ΔtAO/ΔtSP/ΔtL）,确定各期最佳扫描延迟时间。研究结果显示,当采用575 mg·kg-1、3 mL·s-1的造影剂剂量和注射速率时得到的主动脉、门静脉、肝实质CT增强值较高,可获得较好的增强效果。通过时间-密度曲线分别计算小、中、大3种体型犬的ΔtAO分别为7、9、4 s,ΔtSP分别为21、23、17 s,ΔtL分别为41、44、34 s,各期最佳扫描延迟时间可用公式“注射时间+ΔtROI-1/2扫描时间”计算得到。通过临床病例验证,本试验使用的造影剂剂量（575 mg·kg-1）、注射速率（3 mL·s-1）及延迟时间（“注射时间+ΔtAO/ΔtSP/ΔtL-1/2扫描时间”）临床效果较好,可应用于犬肝疾病的CT造影检查。  相似文献   

17.
Gentamicin was administered IM to 6 healthy, mature, lactating cows at a dosage of 3.5 or 5 mg/kg of body weight every 8 hours for 10 consecutive days (total, 30 doses). Endometrial biopsies were done at 72, 136 or 144, and 216 hours after the first dose was administered. On the 10th day, just before the last dose of gentamicin was administered, blood samples (designated 10th-day base-line samples) were obtained, and serial blood samples were obtained for 144 hours after the last injection was given. The cows were catheterized on the 10th day, and urine was obtained for 10 to 18 consecutive hours. Milk samples were also obtained. The cows were slaughtered at different times after the last dose was given, and samples were taken from 22 tissues and organs. Serum, milk, urine, and tissue gentamicin concentrations were determined by radioimmunoassay. Serum gentamicin concentrations were best fitted to a 2-compartment open model. The mean half-lives for absorption, distribution, and elimination were 0.16 +/- 0.14, 2.59 +/- 0.53, and 44.91 +/- 9.38 hours, respectively. Total body clearance and renal clearance were 1.65 +/- 0.69 and 1.32 +/- 0.25 ml/min/kg, respectively. The percentage of the dose excreted unchanged in the urine at 8 hours after the last dose was given was 98 +/- 15. As expected, of the tissues examined, the gentamicin concentrations in the kidney cortex and medulla were 1,500 times greater than those in serum. Renal function remained within the baseline range during the 10 days of gentamicin treatment.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

18.
Differentiating hepatocellular disease versus biliary obstruction can be challenging in dogs presented for icterus. The purpose of this prospective study was to determine the feasibility of percutaneous contrast ultrasound‐guided cholecystography in dogs. Ten normal dogs weighing 7.6–13.0 kg (median 9.8 kg) were recruited. All dogs were considered normal based on complete blood count, serum chemistry profile, ultrasound examination, and percutaneous radiographic cholecystography. Percutaneous contrast ultrasound‐guided cholecystography was performed using 0.5 ml of commercially available contrast agent and two conventional ultrasound machines for simultaneous scanning at two different locations. Two observers independently evaluated the time to initial detection of contrast in the proximal duodenum and duration of contrast enhancement via visual monitoring. Dynamic contrast enhancement was calculated using time‐intensity curves. Mean (±SD) and median (range) of time to initial detection were 8.60 s (± 3.35) and 8.0 s (2.0–11.0), respectively, and mean and median duration were 50.45 s (±23.24) and 53.0 s (20.0 – 70.0), respectively. Mean, median, and range of peak intensity were 114.1 mean pixel value (MPV) (SD ± 30.7), 109.2 MPV, and 79.7–166.7, respectively, and mean, median, and range of time to peak intensity were 26.1 s (SD ± 7.1 s), 24.0 s, and 19.0–41.0 s, respectively. Findings indicated that percutaneous contrast ultrasound‐guided cholecystography is a feasible technique for detecting and quantifying patency of the bile duct in normal dogs. Future studies are needed to assess the diagnostic utility of this technique for dogs with biliary obstruction.  相似文献   

19.
Radiographic and ultrasonic examinations were performed in 12 normal dogs. Initial ultrasound examinations were performed in normally hydrated dogs. The ultrasonic appearance of the diuresed kidney was evaluated after excretory urography and intramuscular administration of furosemide. The dogs were euthanized for anatomic correlation with the sonographic appearance of the kidneys. Renal cortex, medulla, pelvic diverticula, intrarenal vessels, renal pelvis, and renal sinus fat were identified sonographically. Kidney enlargement during diuresis was due to increase renal medullary size. Veterinary Radiology, Vol. 25, No. 4, 1984; pp 173–178.  相似文献   

20.
Helical abdominal computed tomography (CT) was performed in nine normal beagle-mix dogs. Following cephalic vein injection of ionic iodinated contrast medium via power injector (rate 5 ml/s) dual-phase CT was performed in all dogs. A delayed scan was performed in five dogs between 5 and 13 min after the contrast medium injection. The median time of appearance of contrast medium in the aorta and gastroduodenal artery was 6.3 and 7 s, post start injection and 12 and 12.2 s in the gastroduodenal and portal vein, resulting in a purely arterial pancreatic time window of 5-6s. Pancreatic veins and parenchyma remained enhanced until the end of the dynamic scan (40s). The pancreatic parenchyma showed heterogeneous arterial and homogenous venous contrast enhancement which was slightly hypoattenuating compared to the liver. Delayed scans provided best delineation of the pancreas from the liver. The common bile duct could be identified ventral and to the right of the portal vein joining the dorsomedial aspect of proximal duodenum. Because of the very short time window and variable onset of pure arterial enhancement careful planning of dual-phase studies with previous dynamic CT is recommended. Dual-phase CT angiography enables assessment of the arterial supply, parenchymal perfusion and venous drainage of the canine pancreas.  相似文献   

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