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1.
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   

2.
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   

3.
OBJECTIVE: To compare resistance index (RI) and pulsatility index (PI) values of blood flow in arteries of uteroplacental circulation in normal and threatened abortion first trimester pregnancies. STUDY DESIGN: We have analysed 36 pregnant woman between 5th and 12th weeks of pregnancy--17 patients with threatened abortion as a test group and 19 patients with normal intrauterine pregnancy taken as controls. In all patients transvaginal ultrasonography with pulse color Doppler was performed. The RI and PI values were calculated for blood flow velocity waveforms obtained from uterine artery and its branches--arcuate, radial and spiral arteries. RESULTS: In the test group we have analysed 17 flow velocity waveforms from uterine artery (mean RI 0.852; SD 0.080, mean PI 2.324; SD 0.693), 16 from arcuate artery (mean RI 0.638; SD 0.049, mean PI 1.315; SD 0.064,), 17 from radial artery (mean RI 0.638; SD 0.049, mean PI 1.009; SD 0.177) and 15 from spiral artery (mean RI 0.548; SD 0.068, mean PI 0.804; SD 0.160); in controls we have analysed 16 flow velocity waveforms from uterine artery (mean RI 0.866; SD 0.066, mean PI 2.469; SD 0.618), 17 from arcuate artery (mean RI 0.728; SD 0.123, mean PI 1.352; SD 0.362), 19 from radial artery (mean RI 0.630; SD 0.092, mean PI 1.017; SD 0.261) and 16 from spiral artery (mean RI 0.511; SD 0.100, mean PI 0.760; SD 0.202). CONCLUSION: There was no significant difference in mean RI and PI values between normal and abnormal pregnancies. A gradual statistically significant decrease of RI and PI values during time of pregnancy we have observed only in radial arteries in both groups. For other vessels in the control group the RI and PI values tended to decrease during the time of pregnancy while in the test group some even rose up.  相似文献   

4.
Idiopathic intrarenal varices are a rare disease, and only a few cases have been reported. We encountered a patient with intrarenal varices in whom color Doppler sonography was useful for diagnosing and demonstrating this disease, especially with 3D reconstruction of blood flow, which we began using recently.  相似文献   

5.
BACKGROUND: Aim of this work is to evaluate the morphological changes of the waveforms found in the parenchyma of the renal transplant rejection, establishing the prognostic significance. METHODS: 46 patients with symptomatic renal allograft underwent color Doppler ultrasound examination. The ultrasound characteristics were evaluated. The Resistive Index (RI), the morphological waveforms (divided into two groups: group A with regular waveforms, group B with irregular waveforms). Color Doppler pattern (R.I. and waveforms) were compared to histological and cytological specimens and to mean values of creatinine before and after therapy. RESULTS: In group A, the creatinine values varied between the start of rejection symptoms and after some days, giving a significant statistic result. Group B didn't show any important variations. The RI mean value was higher in group B. Significant results concerning correlation between Doppler parameters and histological specimens were not observed. CONCLUSIONS: The conclusion is drawn that in renal transplant rejection it is important to keep in mind also the variation of the waveforms to establish the clinical prognosis.  相似文献   

6.
Remarkable hemodynamics changes that occur in the maternal circulation, the continuous growth and development of the feto-placental circulation is now studied by transvaginal Doppler. This seems to give more light in understanding of the early pregnancy pathophysiology. For the first time, it seems that ultrasound might be able to distinguish different forms of gestational trophoblastic disease. Due to its non-invasiveness and relatively simple and easily performed technique, transvaginal color Doppler might be of considerable clinical value. The other important point is that study results are available immediately for clinical judgement. From our study, we can conclude that transvaginal ultrasound with color and pulsed Doppler is potentially valuable diagnostic tool to differentiate forms of the gestational trophoblastic diseases. On the basis of Doppler findings, the complete mole can be reliably distinguish from the invasive mole or choriocarcinoma. The degree of myometrial invasion can be also assessed. This can be an objective foundation for therapeutical approach. There is no doubt that studies of maternal-fetal circulation in early pregnancy may help for better understanding of physiological and pathophysiological hemodynamic changes. Investigation of maternal (main uterine, arcuate, radial and spiral) arteries; placental (umbilical, chorionic arterioles) vessels and fetal (aorta and intracranial circulation) arteries flow patterns may help in order to diagnose abnormal implantation. More studies are necessary in order the Doppler technique to be used for clinical judgment in early pregnancy. Safety aspects should also be considered. However, potentials of these technique are more then obvious.  相似文献   

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8.
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   

9.
Real time echocardiography associated with pulsed Doppler (duplex) and color (triplex) provide a non invasive technique to determine the vascular morphology of a lesion. The duplex and triplex signal of 35 liver tumors, 23 hepatocarcinomas and 12 angiomas found in the first high frequency signals greater than 1.81 kHz and traced with pulsatile or mixed morphology (pulsed and continuous) were analyzed. The second signals were of low frequency, less than 1 kHz and continuous tracing. It may be concluded than echo-Doppler is a complementary technique to conventional echography and is useful in the diagnosis of hepatocellular carcinoma.  相似文献   

10.
11.
OBJECTIVE: This study proposed to evaluate the efficacy of color Doppler sonography in detecting possible differences in blood flow patterns between malignant and benign cervical lymph nodes. SUBJECTS AND METHODS: During a period of 12 months, the palpable cervical lymph nodes of 48 untreated patients were prospectively evaluated with color Doppler sonography and Doppler flow wave analysis. Histopathologic diagnoses were obtained by sonographically guided fine-needle aspiration biopsy and/or excisional biopsy. RESULTS: We found 16 benign lymph nodes (four were tuberculous lymphadenitis, four were reactive hyperplasia, and eight were unspecified) and 32 malignant lymph nodes (13 were squamous cell carcinomas, nine were adenocarcinomas, four were small-cell carcinomas, three were lymphomas, and three were miscellaneous). Color Doppler flow patterns were seen in six (38%) of the 16 benign lymph nodes and in 29 (91%) of the 32 malignant lymph nodes. Twenty-six (81%) of the 32 malignant lymph nodes had abnormal flow patterns, with resistance indexes less than 0.6. However, three (19%) of the 16 benign lymph nodes also had abnormal flow patterns, and only seven (54%) of 13 squamous cell carcinomas had abnormal flow patterns. CONCLUSION: Color Doppler sonography has limited clinical value in differentiating malignant from benign cervical lymph nodes and in obviating biopsy.  相似文献   

12.
Craniofacial osteomas are benign tumors of the skull base, often involving the paranasal sinuses. The frontal sinus is the most common site of involvement, followed by the ethmoid, maxillary, and sphenoid sinuses, respectively. The growth rate is very slow, and it may take many years for osteomas to become clinically apparent. The origin of these tumors has been ascribed to embryologic tissue maldevelopment, trauma, or infection. The tumors are hard and lobulated with an ivory-like appearance, often mixed with a coarse granular component. The bone is compact or cancellous, with vascular or connective tissue components. The complications of osteoma growth are obstruction of sinus ostia, extension into adjacent bones and the intracranial cavity, and displacement of anatomic structures. Management of uncomplicated sinus osteomas is controversial, since surgery involves serious potential risks. When surgery is performed, these tumors can be successfully managed via endoscopic, open, or combined techniques. This article reviews the clinical findings, diagnostic studies, and treatment of 16 patients with paranasal osteomas. The indications for surgical intervention are discussed.  相似文献   

13.
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   

14.
15.
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   

16.
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   

17.
OBJECTIVE: A hypoechoic rim around a focal liver lesion as revealed by conventional sonography may be present in malignant liver lesions as well as in benign liver lesions. This study evaluated the potential of color Doppler sonography in differentiating various focal liver lesions with a hypoechoic rim. CONCLUSION: Color Doppler sonography may be helpful in distinguishing focal nodular hyperplasia (FNH) from other focal liver lesions. The characteristic finding of blood flow within the hypoechoic rim of FNH is most likely caused by small vessel abnormalities that have previously been described for FNH.  相似文献   

18.
In this study, the reproducibility of color Doppler duplex sonography for repeated measurements of renal blood flow was evaluated in 14 healthy subjects. We examined the reproducibility for different examiners and different time intervals between the examinations. Doppler frequency sonograms were analyzed with several parameters, and statistical evaluation was performed by calculating both the correlation coefficient (r) and coefficient of variation (CV). Peak systolic velocity (S), early diastolic velocity (D1) and mean velocity (MV) showed good reproducibility (r = 0.902-0.992, CV = 2.15-8.16%). On the other hand, end-diastolic velocity (D2), acceleration time (AT) and acceleration index (AI) showed poor reproducibility. We conclude that the reproducibility of this method is acceptable for repeated measurements of renal blood velocity, using suitable parameters S, D1 and MV.  相似文献   

19.
AIM: Acute mesenteric ischemia is difficult to diagnose and is combined with a high mortality. In a retrospective analysis it was investigated how to improve the poor prognosis of the disease. PATIENTS AND METHODS: Between January 1988 through December 1994 a total of 46 patients were operated on for acute mesenteric ischemia. Mesenteric artery occlusion was present in three quarters of the cases (n = 35). These were analysed according to symptoms, diagnosis, mechanism of occlusion, operative procedure and prognosis. Distribution of gender was almost balanced (19 women, 16 men) with a median age of 70.5 years. RESULTS: Embolic arterial occlusion was predominant (n = 22). Most frequently, the superior mesenteric artery was exclusively concerned (n = 22). Serum levels of lactate and leucocytes were preoperatively elevated in over 90% (median values: lactate 53 U/l, leucocytes 15050/ml). In 16 patients diagnosis was made on the ground of clinical parameters and/or angiography, but 19 patients were not diagnosed until operation. 19 patients were operated within 6 hours, 12 patients within 24 hours after admission (> 24 hours: n = 4). Vascular reconstructive procedures only, such as thrombectomy and/or aortomesenteric bypass were performed in 9 cases, in a further 7 cases combined with bowel resection. Bowel resection alone was done in 7 patients, 12 patients had only diagnostic laparotomy. 13 patients survived, 10 of them had been treated with vascular reconstruction. CONCLUSION: Acute mesenteric ischemia ought to be suspected in every patient with uncertain abdominal pain, because only early diagnosis can improve prognosis. Measurement of serum lactate is diagnostically helpful, although not proving. In case of elevated lactate levels and uncertain abdominal symptoms angiography of the mesenteric vessels should be performed early. At operation, blood flow in the mesenteric arteries should be restored whenever possible.  相似文献   

20.
Pure cultures of Chryseomonas luteola and Sphingomonas paucimobilis isolated from Manitoban soils were able to utilize diclofop-methyl (methyl-2-[4-(2,4-dichlorophenoxy)phenoxy] propanoate) as the sole source of carbon and energy. An actively growing culture of C. luteola completely degraded 1.5 micrograms diclofop-methyl.mL-1 to diclofop acid and 4-(2,4-dichlorophenoxy)phenol within 71 h, as determined by gas chromatographic analysis. The accumulation of these metabolites in the growth medium resulted in the cessation of growth, indicating the organism's inability to degrade phenoxyphenol in the presence of diclofop acid. Sphingomonas paucimobilis mineralized 1.5 micrograms diclofop-methyl.mL-1 to diclofop acid within 54 h. A biphasic growth pattern indicated that this organism was capable of degrading diclofop acid to 4-(2,4-dichlorophenoxy)phenol and 2,4-dichlorophenol and (or) phenol. Neither of the organisms was able to utilize 2,4-dichlorophenol as the sole source of carbon and energy.  相似文献   

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