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1.
OBJECTIVE: We compared color Doppler velocity sonography and color Doppler energy sonography for the diagnosis of spermatic cord torsion in a canine model and determined the degree of torsion necessary to acutely halt testicular blood flow. MATERIALS AND METHODS: Spermatic cord torsion was created in five dogs by exposing and rotating the ipsilateral testis 0 degree, 180 degrees, 270 degrees, 360 degrees, 450 degrees, and 540 degrees. Detorsion followed. The testicles were scanned at each torsion stop using both color Doppler velocity sonography and color Doppler energy sonography. Doppler parameters were optimized (by phantom and test scans) and maintained at a tolerable noise level throughout the experiment. Readers who were unaware of the degree of torsion compared flow in the rotated and contralateral control testes. RESULTS: Flow became undetectable by color Doppler velocity sonography and color Doppler energy sonography at 450 degrees in four of five cases and at 540 degrees in one of five cases. We found no significant difference between the velocity and the energy techniques for detecting this absence of flow (p > .05, Wilcoxon test). We found a significant difference in degree of flow for both techniques when comparing controls and all degrees of torsion combined (p < .006, Mann-Whitney test), but significance was achieved at lesser degrees of torsion with the velocity technique than with the energy technique (180 degrees and 360 degrees, respectively, Wilcoxon test). CONCLUSION: Color Doppler energy sonography was not significantly more sensitive than color Doppler velocity sonography for the diagnosis of spermatic cord torsion in this model. Complete occlusion of arterial inflow occurred at 450-540 degrees of torsion.  相似文献   

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In this clinical case we report the use of the superficial femoral vein as an autologous venous interposition graft for the reconstruction of the iliofemoral vein in a 21-year-old female who presented with an asymptomatic primary aneurysm of the left iliofemoral vein. The choice of surgical technique used is discussed.  相似文献   

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BACKGROUND: Aberrant gastric venous drainage (AGVD) into the posterior edge of the medial segment of the liver (segment IV) is the main cause of pseudolesion on computed tomography (CT) during arterial portography. We estimated the prevalence of AGVD into the medial segment of the liver with color and power Doppler ultrasound (US). METHODS: Screening gray-scale and color Doppler and power Doppler US were performed in 100 consecutive patients. AGVD was defined as a venous structure that ascended parallel to the main portal vein and drained independently into segment IV. RESULTS: AGVDs were observed in eight of 100 patients (8%) with color and power Doppler US. Power Doppler US depicted these veins more clearly than did color Doppler US. Gray-scale US did not show any AGVDs. Two of eight patients with AGVDs detected by color Doppler US underwent celiac arteriography and CT during arterial portography (CTAP). In these two patients, celiac arteriography directly demonstrated AGVDs draining into segment IV, which revealed nontumorous perfusion defects (pseudolesions) on CTAP. CONCLUSION: Color and power Doppler US are useful imaging methods for demonstrating AGVDs.  相似文献   

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OBJECTIVES: Prostatic evaluation in men who have undergone prior abdominoperineal resection pose an unusual challenge for the urologist. Neither digital rectal examination nor transrectal ultrasound (TRUS) can be performed. Transperineal ultrasound (TPUS) has been suggested as an alternative means of imaging. This imaging modality was compared directly with the standard TRUS method. METHODS: TPUS was performed with a 4-MHz abdominal probe or biplane multiple frequency probe at a frequency of 5 to 7 MHz followed by TRUS at 7 MHz in 50 consecutive men referred for prostate ultrasound and biopsy who had not undergone prior abdominoperineal resection. Dimensions of the prostate and ultrasound findings such as hypoechoic, anechoic, or hyperechoic areas were noted for each sonographic approach. Volume calculation was performed by the prolate spheroid method. RESULTS: There was good TPUS visualization of the prostate in the transverse plane in 48 (96%) of 50 patients and in the sagittal plane in 45 (90%) of 50 patients. Prostate volume calculation by TPUS correlated well with the volume calculated by TRUS (r=0.876). Twenty-nine patients (58%) were found to have suspicious hypoechoic lesions by TRUS; none were seen by TPUS. Prostatic calcifications were present in 12 patients and were visualized by both TPUS and TRUS in all 12 patients. Six prostate glands demonstrated cystic lesions on TRUS imaging; three of these cystic lesions were also seen with TPUS imaging. CONCLUSIONS: TPUS allows visualization of the prostate with volume determination that is comparable to the volume determination by TRUS. Some intraprostatic findings such as calcifications and cysts can be identified; however, suspicious hypoechoic lesions were not identified by TPUS imaging of the prostate.  相似文献   

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BACKGROUND AND PURPOSE: Power Doppler imaging (PDI) is a new sonographic technique that has recently been introduced for vascular application. Since the technical principles of PDI may provide increased sensitivity to visualize the continuity of blood flow in arterial stenoses, we investigated the diagnostic significance of PDI and the intermethod relationship for the measurement and classification of internal carotid artery (ICA) stenosis in comparison with both color Doppler flow imaging (CDFI) and angiography. METHODS: One hundred patients with a total of 128 ICA stenoses (50% to 69%, n = 37; 70% to 79%, n = 27; 80% to 99%, n = 64) and 12 ICA occlusions were consecutively investigated by means of PDI, CDFI, and intra-arterial angiography (n = 48). Reduction of the intrastenotic lumen was measured on longitudinal and transverse views of PDI and CDFI for the calculation of the degree of diameter and area stenosis, respectively. Angiographic stenosis was determined with the use of the North American Symptomatic Carotid Endarterectomy Trial (NASCET), European Carotid Surgery Trial (ECST), and common carotid (CC) methods. RESULTS: PDI provided significantly more excellent or good (92% versus 79%; P < .01) displays of the intrastenotic lumen than CDFI, particularly in complicated high-grade stenosis. While linear regression analysis demonstrated a high overall correlation between PDI and CDFI for diameter (r = .88; P < .001) and area stenosis (r = .79; P < .001), categorization of ICA stenosis revealed best agreement for 80% to 99% area stenoses. Since angiography frequently either underclassified (NASCET method) or overclassified (ECST, CC methods) the degree of ICA stenosis in comparison to both PDI and CDFI, the sonographic-angiographic correlation was only moderate (regression coefficients ranged from .62 to .70; P < .001). CONCLUSIONS: PDI further improves the assessment of ICA stenosis by providing better visualization of the stenotic vascular lumen than CDFI. Sonographic imaging of the stenotic plaque on both PDI and CDFI provided a direct measurement of the local degree of stenosis, while the angiographic grade of stenosis essentially depended on the method used for evaluation.  相似文献   

7.
Fasciola hepatica miracidia were experimentally introduced into five sites colonized by Lymnaea palustris over a period of 4 or 6 years. In the first four ponds, a progressive increase in the prevalence of the spring-generation juvenile snails was observed (from 0.4 to 18.1%), with a corresponding increase in the shell height of infected snails (from 3.6 to 7.8 mm). In the fifth habitat, the pond dried in 1990 causing the prevalence to drop as compared with the initial values and to subsequently increase in 1991-1992.  相似文献   

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Efficient high-resolution detection of DNA for flow cytometric sorting of X and Y chromosome-bearing sperm is dependent on effectively orientating the sperm head to the laser beam in orthogonally configured flow systems. Normally, a beveled needle is required to enlarge the fraction of properly orientated sperm (flat side facing the laser beam). In this report, a modification to a standard jet-in-air nozzle for improved sperm orientation is presented. Inside the modified nozzle (novel nozzle), orientation forces are applied lower in the nozzle than in the current beveled injection needle system. The nozzle was tested with sperm heads from several species. This study shows that use of the nozzle to orientate cattle, swine, rabbit, mouse, and human sperm effectively improves the percentage of sperm that are properly oriented. The percentage of sperm heads oriented by use of the former system (beveled needle) ranges around 30% for most species. With the newly designed nozzle, that percentage ranges around 60%. At least a twofold increase in analysis is achieved. It was found that, unlike results with the beveled needle, the percentage of properly oriented sperm was independent of the sample rate. The introduced nozzle is a significant improvement over the beveled needle system for the analysis and sorting of sperm on the basis of DNA content. In addition to the improvement in sorted sperm production brought about by the novel nozzle when fitted to standard-speed cell sorters, it clearly also has significant potential for improving the efficiency of the Beltsville Sperm Sexing Technology for separating X and Y chromosome-bearing sperm when adapted to high-speed cell-sorting systems.  相似文献   

10.
Caroli's disease is a rare congenital disorder with multiple cystic dilatations of the intrahepatic bile ducts. In addition to the nonobstructive localized dilatation of the bile ducts, intraluminar bulbar protrusions of the wall and bridge formation across dilated lumina have been demonstrated on sonography and computed tomography. We present a case in which color Doppler sonography clearly showed a blood flow signal toward the periphery of the liver in the protrusion of the dilated intrahepatic bile ducts. Color Doppler sonography is a useful noninvasive method for evaluating the malformation of Caroli's disease.  相似文献   

11.
In two similar cases of irreducible intussusception with wall necrosis and perforation, symptoms had begun 24 h before admission and the plain radiographs showed signs of small-bowel obstruction. The sonographic (US) appearances, however, were different: color Doppler (CD) US showed vascular flow in the intussuscepted bowel in one case and no flow in the other. After radio-clinical assessment, both children underwent surgery and an intestinal resection had to be performed, manual reduction being impossible. The reliability of the US findings and the prognostic value of CD and power Doppler US in determining the viability of the intussuscepted bowel are discussed with a review of the literature.  相似文献   

12.
In an earlier paper, we reported our scoring system for the diagnosis of adenomyosis by gray scale transvaginal sonography. In this study we evaluated 44 benign uterine masses (adenomyosis and myomas) and seven uterine malignancies. We used transvaginal color and pulsed Doppler imaging to determine whether this technique is useful to differentiate adenomyosis from uterine malignancies. The peak systolic velocity and the resistive index of intratumoral vessels were studied. The differences in these parameters for adenomyosis and uterine malignancies were statistically significant. Our results suggest that this technique is useful to differentiate adenomyosis from uterine malignancies.  相似文献   

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This study reports the experience achieved with duplex and color Doppler ultrasonography in 120 impotent patients. The following morphodynamic parameters of the cavernosal arteries were studies before and after intracorporal injection of a mixture of vasoactive drugs: arterial diameter, wall pulsatility, morphology of the spectral waveform, peak systolic velocity, end diastolic velocity and flow volume. The veno-occlusive mechanism of the corpora cavernosa was studied directly by determination of flow along the deep dorsal vein of the penis and indirectly by serial evaluation of the diastolic flow of the cavernous arteries.  相似文献   

16.
RATIONALE AND OBJECTIVES: This study sought to evaluate prospectively the diagnostic potential of unenhanced and enhanced color Doppler and power Doppler for the differentiation of tumors and tumorlike lesions of the breast. METHODS: Ninety-two patients with 110 tumors or tumorlike lesions of the breast were investigated by unenhanced and enhanced color and power Doppler ultrasound. The sonomorphologic aspects of vascularization were analyzed. In addition, maximal systolic frequency shift, resistance, and pulsatility indices were determined. RESULTS: In 15 (24%) of 63 primary carcinomas, 15 (68%) of 22 fibroadenomas, and all (100%) of 14 postoperative lesions, the sonomorphologic analysis for the differential diagnosis of breast tumors was improved after contrast enhancement in color Doppler mode. In comparing unenhanced color Doppler to power Doppler, the latter was found to be slightly superior (sensitivity, 60% vs. 67%; specificity, 39% vs. 45%, respectively); after enhancement, both modes were equivalent (sensitivity, 100% vs. 100%; specificity, 95% vs. 95%, respectively). Signal enhancement resulted in a significant improvement in sensitivity and specificity (P < 0.01). Typical signs of malignancy were irregular vessel calibers, serpiginous courses, penetration of the tumor's margin, and irregular reticular vascularization. The quantitative parameters proved not to be helpful for the differential diagnosis of breast tumors. CONCLUSIONS: By improved analysis of the vascularization pattern, d-galactose-enhanced color Doppler sonography was found to provide more reliable differential diagnostic information than unenhanced Doppler ultrasound in tumors and tumorlike lesions of the breast.  相似文献   

17.
The effect of various anionic surfactants on the initial rate of 5-aminosalicylic acid peroxidation with horseradish peroxidase was studied. With increasing surfactant concentration, this rate first decreased, then increased, and again decreased. We conclude that these changes were due to an inhibition of the enzyme, a subsequent change in the enzyme conformation accompanied by the enhanced accessibility of its active site to the substrate, and the final protein denaturation, respectively.  相似文献   

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The purpose of this study was to evaluate the short-term reproducibility, the long-term reproducibility, and the reproducibility of the measurements made between two different examiners of blood-flow velocity in extraocular vessels using color Doppler imaging (CDI). In a group of 10 healthy volunteers, measurements of the peak-systolic velocity (PSV), end-diastolic velocity (EDV), and resistivity index (RI) in the ophthalmic artery and the central retinal artery as well as one lateral and one medial short posterior ciliary artery were performed. The best intraindividual reproducibility, expressed as the relative error, was found for the PSV and RI measured in the ophthalmic artery (OA; PSV 5.9%, RI 3.1%) and the central retinal artery (CRA; PSV 7.7%, RI 4.7%). The PSV and RI determined in the posterior ciliary arteries were less reproducible but as much so as the EDV measured in the OA (11.8%) and CRA (19.9%). No systematic trend could be found between the first and second measurements. However, the long-term fluctuation was considerable high. Measurements of PSVs showed good concurrence between the two observers in all four vessels measured. The EDVs and RIs differed statistically significantly between the two observers. This difference was most pronounced in the posterior ciliary arteries.  相似文献   

20.
Because of various contradictory reports in the literature and an increasingly urgent need for preoperative evaluation of adnexal masses before laparoscopic surgery, our aim was to disclose if examination by means of color Doppler ultrasound is useful in distinguishing benign from malignant adnexal tumors in our population. Prior to surgery, pulsed color Doppler velocimetry of the adnexal blood supply was performed in a prospective study in 80 patients with benign and 40 with malignant adnexal tumors. Vascularization was equally frequent in both groups of tumors. Blood vessels of benign tumors had a diffuse, intraseptal or intraproliferative location significantly more often and malignant tumor vessels more often exhibited a diffuse, intraseptal or intraproliferative location (p < 0.01). The mean value of RI+/-SD was 0.56+/-0.14 in benign and 0.33+/-0.13 in malignant tumors. The differences in RI between benign and malignant tumors are statistically significant (p < 0.01). In detecting malignant adnexal tumors, the sensitivity of RI < or = 0.40 is 82%, its specificity 97%, positive predictive value 94%, negative predictive value 92% and its accuracy 92%. The analysis of vascularization presence seems not to have any value in predicting the nature of adnexal tumors, and blood vessels arrangement, as well as measured RI < or = 0.40, allows us to predict the presence of malignancy with limited reliability.  相似文献   

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