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Doppler Ultrasound (doppler + ultrasound)
Kinds of Doppler Ultrasound Terms modified by Doppler Ultrasound Selected AbstractsGuidelines for the Evaluation of Prosthetic Valves with Echocardiography and Doppler Ultrasound: Value and LimitationsECHOCARDIOGRAPHY, Issue 1 2010Fadi G. Hage M.D. No abstract is available for this article. [source] Doppler Ultrasound in MiceECHOCARDIOGRAPHY, Issue 1 2007Jörg Stypmann Color, power, spectral, and tissue Doppler have been applied to mice. Due to the noninvasive nature of the technique, serial intraindividual Doppler measurements of cardiovascular function are feasible in wild-type and genetically altered mice before and after microsurgical procedures or to follow age-related changes. Fifty-megahertz ultrasound biomicroscopy allows to record the first beats of the embryonic mouse heart at somite stage 5, and the first Doppler-flow signals can be recorded after the onset of intrauterine cardiovascular function at somite stage 7. Using 10- to 20-MHz ultrasound transducers in the mouse embryo, cardiac, and circulatory function can be studied as early as 7.5 days after postcoital mucous plug. Postnatal Doppler ultrasound examinations in mice are possible from birth to senescent age. Several strain-, age-, and gender-related differences of Doppler ultrasound findings have been reported in mice. Results of Doppler examinations are influenced by the experimental settings as stress testing or different forms of anesthesia. This review summarizes the present status of Doppler ultrasound examinations in mice and animal handling in the framework of a comprehensive phenotype characterization of cardiac contractile and circulatory function. [source] Imaging of the lymphatic system: new horizons,CONTRAST MEDIA & MOLECULAR IMAGING, Issue 6 2006Tristan Barrett Abstract The lymphatic system is a complex network of lymph vessels, lymphatic organs and lymph nodes. Traditionally, imaging of the lymphatic system has been based on conventional imaging methods like computed tomography (CT) and magnetic resonance imaging (MRI), whereby enlargement of lymph nodes is considered the primary diagnostic criterion for disease. This is particularly true in oncology, where nodal enlargement can be indicative of nodal metastases or lymphoma. CT and MRI on their own are, however, anatomical imaging methods. Newer imaging methods such as positron emission tomography (PET), dynamic contrast-enhanced MRI (DCE-MRI) and color Doppler ultrasound (CDUS) provide a functional assessment of node status. None of these techniques is capable of detecting flow within the lymphatics and, thus, several intra-lymphatic imaging methods have been developed. Direct lymphangiography is an all-but-extinct method of visualizing the lymphatic drainage from an extremity using oil-based iodine contrast agents. More recently, interstitially injected intra-lymphatic imaging, such as lymphoscintigraphy, has been used for lymphedema assessment and sentinel node detection. Nevertheless, radionuclide-based imaging has the disadvantage of poor resolution. This has lead to the development of novel systemic and interstitial imaging techniques which are minimally invasive and have the potential to provide both structural and functional information; this is a particular advantage for cancer imaging, where anatomical depiction alone often provides insufficient information. At present the respective role each modality plays remains to be determined. Indeed, multi-modal imaging may be more appropriate for certain lymphatic disorders. The field of lymphatic imaging is ever evolving, and technological advances, combined with the development of new contrast agents, continue to improve diagnostic accuracy. Published in 2006 by John Wiley & Sons, Ltd. [source] Cerebral oxygenation decreases during exercise in humans with beta-adrenergic blockadeACTA PHYSIOLOGICA, Issue 3 2009T. Seifert Abstract Aim:, Beta-blockers reduce exercise capacity by attenuated increase in cardiac output, but it remains unknown whether performance also relates to attenuated cerebral oxygenation. Methods:, Acting as their own controls, eight healthy subjects performed a continuous incremental cycle test to exhaustion with or without administration of the non-selective beta-blocker propranolol. Changes in cerebral blood flow velocity were measured with transcranial Doppler ultrasound and those in cerebral oxygenation were evaluated using near-infrared spectroscopy and the calculated cerebral mitochondrial oxygen tension derived from arterial to internal jugular venous concentration differences. Results:, Arterial lactate and cardiac output increased to 15.3 ± 4.2 mm and 20.8 ± 1.5 L min,1 respectively (mean ± SD). Frontal lobe oxygenation remained unaffected but the calculated cerebral mitochondrial oxygen tension decreased by 29 ± 7 mmHg (P < 0.05). Propranolol reduced resting heart rate (58 ± 6 vs. 69 ± 8 beats min,1) and at exercise exhaustion, cardiac output (16.6 ± 3.6 L min,1) and arterial lactate (9.4 ± 3.7 mm) were attenuated with a reduction in exercise capacity from 239 ± 42 to 209 ± 31 W (all P < 0.05). Propranolol also attenuated the increase in cerebral blood flow velocity and frontal lobe oxygenation (P < 0.05) whereas the cerebral mitochondrial oxygen tension decreased to a similar degree as during control exercise (delta 28 ± 10 mmHg; P < 0.05). Conclusion:, Propranolol attenuated the increase in cardiac output of consequence for cerebral perfusion and oxygenation. We suggest that a decrease in cerebral oxygenation limits exercise capacity. [source] Utility of Intralesional Sclerotherapy with 3% Sodium Tetradecyl Sulphate in Cutaneous Vascular MalformationsDERMATOLOGIC SURGERY, Issue 3 2010MNAMS, SUJAY KHANDPUR MBBS BACKGROUND Vascular malformations have devastating cosmetic effects in addition to being associated with pain and bleeding. Sclerotherapy has been successfully used in treating complicated hemangiomas and vascular malformations. OBJECTIVES To assess the efficacy of sclerotherapy with 3% sodium tetradecyl sulphate (STS) in venous and lymphatic malformations. MATERIALS AND METHOD We performed sclerotherapy with 3% STS in 13 patients with venous malformations and microcystic lymphatic malformation, all low-flow malformations and with extent predominantly to the subcutis, confirmed using Doppler ultrasound. Lesions were located on the face, lower lip, flanks, buttocks, and extremities. Patients presented for cosmetic reasons, pain, or bleeding. Sclerotherapy was undertaken as an office procedure without any radiological guidance and therapy repeated every 3 weeks. Therapeutic efficacy was assessed subjectively clinically and photographically. RESULTS The lesions regressed by 90% to 100% in 11 cases after a mean of four injections, with no improvement in two cases (one each of venous malformation and lymphatic malformation). Complications included cutaneous blister formation, erosions, and crusting at injection site in seven cases and atrophic scarring in four patients. CONCLUSIONS Sclerotherapy with 3% STS is a simple, safe, and effective modality for venous malformations and can be undertaken as an office procedure in lesions limited to the subcutis. The authors have indicated no significant interest with commercial supporters. [source] TBI or not TBI: that is the question.DIABETIC MEDICINE, Issue 7 2001Is it better to measure toe pressure than ankle pressure in diabetic patients? Abstract Aims Measurement of ankle blood pressure is a simple method of assessing lower limb arterial blood supply. However, its use in diabetes has been questioned due to the presence of medial artery calcification. Measurement of toe blood pressure has been advocated as an alternative but it is technically more difficult. The aim of this study was to obtain information to guide clinicians as to when pressure measurements should be taken at the toe. Methods Ankle brachial index (ABI) and toe brachial index (TBI) were measured by Doppler ultrasound, or photoplethysmography on 174 subjects with diabetes and 53 control subjects. The Bland and Altman method, and the Cohen's method of measuring agreement between two tests were used to compare ABI with TBI. Results The mean differences between ABI and TBI in control and diabetic subjects are 0.40 ± 0.13 and 0.37 ± 0.15, respectively. Nearly all diabetic patients with an ABI <,1.3 have an ABI,TBI gradient falling within the normal range established from the non-diabetic cohort. In contrast, the majority of diabetic subjects with an ABI ,,1.3 have ABI,TBI differences outside this range. When patients are categorized according to ABI and TBI, there is also good agreement between the tests when ABI is low or normal (84% and 78% agreement, respectively), but not when ABI is elevated. Conclusion In the majority of patients with diabetes, assessment of TBI conveys no advantage over ABI in determining perfusion pressure of the lower limbs. Only in those patients with overt calcification, which gives an ABI ,,1.3, are toe pressure measurements superior. This guideline should simplify assessment and treatment of diabetic patients with disease of the lower limbs. Diabet. Med. 18, 528,532 (2001) [source] Fine-needle aspiration cytology in the follow-up of Hodgkin lymphomaDIAGNOSTIC CYTOPATHOLOGY, Issue 7 2008Pio Zeppa M.D. Abstract Hodgkin lymphoma (HL) is characterized by long survival and risk of relapse and second neoplasm. The aim of this study is to evaluate the possibility of improving the accuracy of fine-needle cytology (FNC) in HL follow-up using Power Doppler ultrasound (US) assistance and immediate microscopic evaluation (ICE). The study was performed in two consecutive groups of 200 FNC in HL patients. In the first group FNC of palpable lymph-nodes or extra lymph-nodal masses were performed without US assistance except for impalpable and/or deep located masses (nonassisted group); In the second group, all the FNC were performed under Power Doppler US assistance with ICE and immediately repeated in inadequate cases (assisted group). Cytological diagnoses were controlled by histology (61) or clinical follow-up (69); sensitivity and specificity were calculated in the two groups and to evaluate the effect of Power Doppler alone, adequate cases were compared with the total number of FNC in each of the two groups. FNC identified 90 negative cases, 3 false negatives, 70 HL relapse, 16 inadequate and 14 suspicious; second neoplasia were diagnosed in 12 cases and all histologically confirmed. Sensitivity and specificity were 64 and 84% in the nonassisted group and 86 and 94% in the assisted group and there were significant differences between the number of adequate cases v.s. the total number of FNC in each of the two groups. Sensitivity and specificity in assisted FNC are higher than in nonassisted ones. The main advantage of assisted FNC in the follow-up of HL is to produce accurate diagnoses avoiding invasive biopsies. Diagn. Cytopathol. 2008;36:467,472. © 2008 Wiley-Liss, Inc. [source] The Effect of Angiotensin II Type-1 Receptor Gene Polymorphisms on Doppler Blood Flow Parameters of Carotid and Brachial Arteries in Patients with Myocardial InfarctionECHOCARDIOGRAPHY, Issue 7 2006Onder Ozturk M.D. Background: Genetic influence on Doppler blood flow parameters of carotid and brachial arteries (BA) is uncertain. We investigated the relationship between the angiotensin II type-1 receptor (AT1R) gene polymorphism and the blood flow characteristics of common carotid arteries (CCA) and BA by color Doppler ultrasound (CDUS) in patients with a first anterior acute myocardial infarction (AMI). Methods and Results: Sixty-seven patients (15 women and 52 men), aged 25,77 years, with anterior AMI were studied. The AT1R genotypes were established. Based on the polymorphism of the AT1R, they were classified into three groups: AT1R AA genotype (Group1, n = 42 patients), AT1R AC genotype (Group 2, n = 17 patients), and AT1R CC genotype (Group 3, n = 8 patients). Peak-systolic velocity (PSV) and end-diastolic velocity (EDV) of right and left CCA, PSV of right BA, and intimal-medial thickness (IMT) of both CCA were measured by CDUS. All results evaluated statistically. The AT1R genotypes were distributed as follows: 63% AA, 25% AC, and 12% CC. PSV of BA and both CCA were higher in patients with CC and AC than AA (P < 0.05). Also, IMT of both CCA were also higher in the same groups (P < 0.05). Conclusions: Our results suggest that AT1R gene polymorphism influences Doppler blood flow parameters of both BA and CCA, and IMT of CCA. Although further studies are required. [source] First-trimester fetal heart rate in mothers with opioid addictionADDICTION, Issue 7 2010Maximilian Schmid ABSTRACT Aim To investigate the difference in fetal heart rate of opioid-dependent mothers compared to non-dependent mothers in the first trimester of pregnancy. Design The data of 74 consecutive singleton pregnancies of mothers enrolled in a maintenance programme for opioid-dependent women was matched to 74 non-exposed singleton pregnancies by maternal age, crown,rump length, smoking status, ethnic background and mode of conception. Measurement Fetal heart rate measured as part of first-trimester screening by Doppler ultrasound between 11+0 and 13+6 gestational weeks was compared retrospectively. Findings The mean fetal heart rate in opioid-dependent mothers was 156.0 beats per minute (standard deviation 7.3) compared to 159.6 (6.5) in controls. The difference in fetal heart rate was significant (P = 0.02). There was a significant difference in mean maternal body mass index (P = 0.01) but not in mean nuchal translucency (P = 0.3), gestational age (0.5), fetal gender (P = 0.3) and parity (P = 0.3) between both groups. Fifty-five per cent (41 of 74) of cases were taking methadone, 30% (22 of 74) buprenorphine and 15% (11 of 74) were taking slow-release morphines throughout the pregnancy. Conclusions In fetuses of opioid-dependent mothers a decreased fetal heart rate can already be observed between 11+0 and 13+6 gestational weeks. The effect of opioid intake needs to be taken into consideration when interpreting fetal heart rate in opioid-dependent mothers at first-trimester screening. [source] Modelflow estimates of cardiac output compared with Doppler ultrasound during acute changes in vascular resistance in womenEXPERIMENTAL PHYSIOLOGY, Issue 4 2010Kenneth S. Dyson We compared Modelflow (MF) estimates of cardiac stroke volume (SV) from the finger pressure-pulse waveform (Finometer®) with pulsed Doppler ultrasound (DU) of the ascending aorta during acute changes in total peripheral resistance (TPR) in the supine and head-up-tilt (HUT) postures. Twenty-four women were tested during intravenous infusion of 0.005 or 0.01 ,g kg,1 min,1 isoprenaline, 10 or 50 ng kg,1 min,1 noradrenaline and 0.3 mg sublingual nitroglycerine. Responses to static hand-grip exercise (SHG), graded lower body negative pressure (LBNP, from ,20 to ,45 mmHg) and 45 deg HUT were evaluated on separate days. Bland,Altman analysis indicated that SVMF yielded lower estimates than SVDU during infusion of 0.01 ,g kg,1 min,1 isoprenaline (SVMF 92.7 ± 15.5 versus SVDU 104.3 ± 22.9 ml, P= 0.03) and SHG (SVMF 78.8 ± 12.0 versus SVDU 106.1 ± 28.5 ml, P < 0.01), while larger estimates were recorded with SVMF during ,45 mmHg LBNP (SVMF 52.6 ± 10.7 versus SVDU 46.2 ± 14.5 ml, P= 0.04) and HUT (SVMF 59.3 ± 13.6 versus SVDU 45.2 ± 11.3 ml, P < 0.01). Linear regression analysis revealed a relationship (r2= 0.41, P < 0.01) between the change in TPR from baseline and the between-methods discrepancy in SV measurements. This relationship held up under all of the experimental protocols (regression for fixed effects, P= 0.46). These results revealed a discrepancy in MF estimates of SV, in comparison with those measured by DU, during acute changes in TPR. [source] The effect of hypoxia on pulmonary O2 uptake, leg blood flow and muscle deoxygenation during single-leg knee-extension exerciseEXPERIMENTAL PHYSIOLOGY, Issue 3 2004Darren S. DeLorey The effect of hypoxic breathing on pulmonary O2 uptake (VO2p), leg blood flow (LBF) and O2 delivery and deoxygenation of the vastus lateralis muscle was examined during constant-load single-leg knee-extension exercise. Seven subjects (24 ± 4 years; mean ±s.d.) performed two transitions from unloaded to moderate-intensity exercise (21 W) under normoxic and hypoxic (PETO2= 60 mmHg) conditions. Breath-by-breath VO2p and beat-by-beat femoral artery mean blood velocity (MBV) were measured by mass spectrometer and volume turbine and Doppler ultrasound (VingMed, CFM 750), respectively. Deoxy-(HHb), oxy-, and total haemoglobin/myoglobin were measured continuously by near-infrared spectroscopy (NIRS; Hamamatsu NIRO-300). VO2p data were filtered and averaged to 5 s bins at 20, 40, 60, 120, 180 and 300 s. MBV data were filtered and averaged to 2 s bins (1 contraction cycle). LBF was calculated for each contraction cycle and averaged to 5 s bins at 20, 40, 60, 120, 180 and 300 s. VO2p was significantly lower in hypoxia throughout the period of 20, 40, 60 and 120 s of the exercise on-transient. LBF (l min,1) was approximately 35% higher (P > 0.05) in hypoxia during the on-transient and steady-state of KE exercise, resulting in a similar leg O2 delivery in hypoxia and normoxia. Local muscle deoxygenation (HHb) was similar in hypoxia and normoxia. These results suggest that factors other than O2 delivery, possibly the diffusion of O2, were responsible for the lower O2 uptake during the exercise on-transient in hypoxia. [source] Changes in Cerebral Blood Flow During and After 48 H of Both Isocapnic and Poikilocapnic Hypoxia in HumansEXPERIMENTAL PHYSIOLOGY, Issue 5 2002Marc J. Poulin During acclimatization to the hypoxia of altitude, the cerebral circulation is exposed to arterial hypoxia and hypocapnia, two stimuli with opposing influences on cerebral blood flow (CBF). In order to understand the resultant changes in CBF, this study examined the responses of CBF during a period of constant mild hypoxia both with and without concomitant regulation of arterial PCO2. Nine subjects were each exposed to two protocols in a purpose-built chamber: (1) 48 h of isocapnic hypoxia (Protocol I), where end-tidal PO2 (PET,O2) was held at 60 Torr and end-tidal PCO2 (PET,CO2) at the subject's resting value prior to experimentation; and (2) 48 h of poikilocapnic hypoxia (Protocol P), where PET,O2 was held at 60 Torr and PET,CO2 was uncontrolled. Transcranial Doppler ultrasound was used to assess CBF. At 24 h intervals during and after the hypoxic exposure CBF was measured and the sensitivity of CBF to acute variations in PO2 and PCO2 was determined. During Protocol P, PET,CO2 decreased by 13% (P < 0.001) and CBF decreased by 6% (P < 0.05), whereas during Protocol I, PET,CO2 and CBF remained unchanged. The sensitivity of CBF to acute variations in PO2 and PCO2 increased by 103% (P < 0.001) and 28% (P < 0.01), respectively, over the 48 h period of hypoxia. These changes did not differ between protocols. In conclusion, CBF decreases during mild poikilocapnic hypoxia, indicating that there is a predominant effect on CBF of the associated arterial hypocapnia. This fall occurs despite increases in the sensitivity of CBF to acute variations in PO2/PCO2 arising directly from the hypoxic exposure. [source] Paraoxonase-1 (PON1) activity as a risk factor for atherosclerosis in chronic renal failure patientsHEMODIALYSIS INTERNATIONAL, Issue 4 2008Saeed Abdelwhab SAEED Abstract Paraoxonase is a high-density lipoprotein-associated enzyme and has been shown to reduce the susceptibility to low-density lipoprotein peroxidation. This study aimed to investigate the activity of serum paraoxonase in uremic patients on hemodialysis (HD) and in the predialysis period, and to evaluate the correlations of vascular disease with paraoxonase activity. Thirty patients with chronic renal failure (CRF) undergoing HD (group 1), 30 patients with CRF under conservative treatment (group 2), and 30 healthy controls (group 3) were included. Basal, salt-stimulated, and arylesterase activity were tested by UV spectrophotometry. Serum lipid parameters were determined. B-Mode Doppler ultrasound was used to assess common carotid intima-media thickness (IMT). Basal paraoxonase, salt-stimulated, and arylesterase activity showed no significant difference between group 1 and group 2. However, it was significantly lower in group 1 and in group 2 than controls. Carotid IMT was significantly higher in group 1 than group 2 and both were significantly higher than controls. Basal paraoxonase-1 (PON1), salt-stimulated PON1, and arylesterase activity correlate with BUN, but only basal PON1 and salt-stimulated PON1 correlate with serum albumin. Linear regression showed that the most significant determinant of carotid IMT was PON1 arylesterase activity in group 1 and arylesterase activity and basal PON1 activity in group 2. Patients with CRF, whether under HD or conservative treatment, have reduced basal and stimulated paraoxonase activities, and this could be an important factor causing increased vascular disease in those patients. Modifying this factor can be of great value to protect against this common complication. [source] Diagnosis of pancreatic cancerHPB, Issue 5 2006Fumihiko Miura Abstract The ability to diagnose pancreatic carcinoma has been rapidly improving with the recent advances in diagnostic techniques such as contrast-enhanced Doppler ultrasound (US), helical computed tomography (CT), enhanced magnetic resonance imaging (MRI), and endoscopic US (EUS). Each technique has advantages and limitations, making the selection of the proper diagnostic technique, in terms of purpose and characteristics, especially important. Abdominal US is the modality often used first to identify a cause of abdominal pain or jaundice, while the accuracy of conventional US for diagnosing pancreatic tumors is only 50,70%. CT is the most widely used imaging examination for the detection and staging of pancreatic carcinoma. Pancreatic adenocarcinoma is generally depicted as a hypoattenuating area on contrast-enhanced CT. The reported sensitivity of helical CT in revealing pancreatic carcinoma is high, ranging between 89% and 97%. Multi-detector-row (MD) CT may offer an improvement in the early detection and accurate staging of pancreatic carcinoma. It should be taken into consideration that some pancreatic adenocarcinomas are depicted as isoattenuating and that pancreatitis accompanied by pancreatic adenocarcinoma might occasionally result in the overestimation of staging. T1-weighted spin-echo images with fat suppression and dynamic gradient-echo MR images enhanced with gadolinium have been reported to be superior to helical CT for detecting small lesions. However, chronic pancreatitis and pancreatic carcinoma are not distinguished on the basis of degree and time of enhancement on dynamic gadolinium-enhanced MRI. EUS is superior to spiral CT and MRI in the detection of small tumors, and can also localize lymph node metastases or vascular tumor infiltration with high sensitivity. EUS-guided fine-needle aspiration biopsy is a safe and highly accurate method for tissue diagnosis of patients with suspected pancreatic carcinoma. 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET) has been suggested as a promising modality for noninvasive differentiation between benign and malignant lesions. Previous studies reported the sensitivity and specificity of FDG-PET for detecting malignant pancreatic tumors as being 71,100% and 64,90%, respectively. FDG-PET does not replace, but is complementary to morphologic imaging, and therefore, in doubtful cases, the method must be combined with other imaging modalities. [source] Penile pharmacotesting in diagnosing male erectile dysfunction: evidence for lack of accuracy and specificityINTERNATIONAL JOURNAL OF ANDROLOGY, Issue 1 2002Antonio Aversa Penile pharmacotesting (PPT) with alprostadil (PGE1) represents the most common diagnostic approach to male erectile dysfunction (ED). A positive response , i.e. normal erectile rigidity of sustained duration , is presumed to exclude venous or arterial pathology with enough accuracy. To test this assumption we compared PPT vs. flowmetric results obtained by colour-duplex Doppler ultrasound (CDDU) in patients (pts) undergoing diagnostic evaluation for ED under conditions of maximal cavernous relaxation. A total of 195 non-consecutive impotent pts were diagnosed after dynamic CDDU as non-vasculogenic (NOR), or having arteriogenic (AR), veno-occlusive (VO) or mixed (MX) ED. Maximal erection obtained after PPT was scored as: type-1 (full tumescence , no sustained rigidity, angle on the abdominal plane >90°), type-2 (sustained partial erection, valid for intromission, angle=90°) and type-3 (sustained full erection, angle <90°). Comparing PPT with flowmetric results, we found that a type-3 response had 20% false negative diagnosis of NOR (17% of AR- and 3% of VO- and MX-ED, respectively), while a type-2 response had 63% false negative diagnosis (20% of AR, 37% of VO- and 6% MX-ED, respectively). Type-1 response was associated with the presence of VO dysfunction in 99% of cases. These data suggest that a positive response to PPT (type-2 and type-3) assessed by the visual rating of erection is associated with both arterial (up to 20%) and/or VO (up to 43%) ED, as detected by CDDU. We conclude that PPT alone is a misleading diagnostic test to exclude vascular ED and that dynamic CDDU should be offered to pts investigated for male ED. [source] Tumoricidal activity of high-dose tumor necrosis factor-, is mediated by macrophage-derived nitric oxide burst and permanent blood flow shutdownINTERNATIONAL JOURNAL OF CANCER, Issue 2 2008Chandrakala Menon Abstract This study investigates the role of tumor nitric oxide (NO) and vascular regulation in tumor ulceration following high-dose tumor necrosis factor-, (TNF) treatment. Using TNF-responsive (MethA) and nonresponsive (LL2) mouse tumors, tumor NO concentration was measured with an electrochemical sensor and tumor blood flow by Doppler ultrasound. Mice were also pretreated with a selective inducible nitric oxide synthase (iNOS) inhibitor, 1400 W. Tumors harvested from TNF-treated mice were cryosectioned and immunostained for murine macrophages, or/and iNOS. MethA tumor-bearing mice were depleted of macrophages. Pre- and post-TNF tumor NO levels were measured continuously, and mice were followed for gross tumor response. In MethA tumors, TNF caused a 96% response rate, and tumor NO concentration doubled. Tumor blood flow decreased to 3% of baseline by 4 hr and was sustained at 24 hr and 10 days post-TNF. Selective NO inhibition with 1400 W blocked NO rise and decreased response rate to 38%. MethA tumors showed tumor infiltration by macrophages post-TNF and the pattern of macrophage immunostaining overlapped with iNOS immunostaining. Depletion of macrophages inhibited tumor NO increase and response to TNF. LL2 tumors had a 0% response rate to TNF and exhibited no change in NO concentration. Blood flow decreased to 2% of baseline by 4 hr, recovered to 56% by 24 hr and increased to 232% by 10 days. LL2 tumors showed no infiltration by macrophages post-TNF. We conclude that TNF causes tumor infiltrating, macrophage-derived iNOS-mediated tumor NO rise and sustained tumor blood flow shutdown, resulting in tumor ulceration in the responsive tumor. © 2008 Wiley-Liss, Inc. [source] The value of Doppler ultrasound in diagnosis in 25 cases of furunculoid myiasisINTERNATIONAL JOURNAL OF DERMATOLOGY, Issue 1 2005Marco R. Quintanilla-Cedillo MD Background, The larvae of the botfly Dermatobia hominis cause furunculoid myiasis in endemic areas. Lack of knowledge of this condition outside these areas leads to confusion in diagnosis and delays appropriate treatment. Objective, To describe the clinical findings of furunculoid myiasis encountered in Quintana Roo, in the south-east of Mexico. Materials and methods, We performed an observational study on 25 cases diagnosed over a period of 4 years. Results, Diagnosis of furunculoid myiasis was made in 14 males and 11 females with an average age of 24.5 years. Most of our patients were students, farmers, or housewives. The number of lesions varied from one to four. In 20% of cases, more than one parasite was present in each lesion. The scalp was the most commonly affected region (40%), followed by the trunk and the extremities. Doppler ultrasound study (DUSG) of the furuncle-like lesions confirmed the clinical diagnosis in all cases. Conclusions, Furunculoid myiasis is frequent in the state of Quintana Roo, Mexico. We found no association with occupation, gender, social background or age. DUSG can be used to evaluate the number of parasites per furunculoid lesion avoiding misdiagnoses and treatment delays. [source] Ejaculatory dysfunction caused by the new ,1 -blocker silodosin: A preliminary study to analyze human ejaculation using color Doppler ultrasonographyINTERNATIONAL JOURNAL OF UROLOGY, Issue 10 2008Atsushi Nagai Objectives: In order to clinically investigate the mechanism of ejaculatory dysfunction attributable to the ,1 -blocker silodosin, a real-time observation of ejaculation by healthy males was performed. Methods: Following intake of silodosin, a newly developed selective ,1 -blocker for benign prostatic hypertrophy, ejaculation was dynamically observed using color Doppler ultrasound in three healthy males. Normal ejaculation was also investigated in the same manner. Results: With silodosin intake, no antegrade ejaculation was observed in cases 1 or 2. In case 1, seminal fluid slowly but continuously flowed out from the seminal vesicles into the bladder. In case 2, only a small amount of seminal fluid flowed into the bladder during the ejaculatory sensation. In case 3, ejection of a small amount of semen from the external urethral orifice was observed and inflow of a small amount of seminal fluid into the bladder was also captured. Without silodosin intake, all three subjects exhibited antegrade ejaculation. Conclusions: The mechanism of ejaculatory dysfunction is intricately related to retrograde ejaculation (retrograde inflow of seminal fluid), insufficient contraction of the seminal vesicles, and insufficient rhythmic contraction of the muscles of the pelvic floor. [source] Assessment of renal function with color Doppler ultrasound in autosomal dominant polycystic kidney diseaseINTERNATIONAL JOURNAL OF UROLOGY, Issue 3 2001Akira Kondo Abstract Background: Measurement of renal blood flow by color Doppler ultrasound is useful for assessment of renal function in a variety of renal disorders. In autosomal dominant polycystic kidney disease (ADPKD), however, it might be difficult to visualize interlobar arteries because of deformity of renal structure. To evaluate the usefulness of color Doppler in ADPKD, parameters determined by blood flow examination were compared with the results of ordinal renal function tests. Methods: Twenty-one patients with ADPKD were examined by color Doppler ultrasound measurement. In each patient, 10 interlobar arteries in both kidneys were investigated. Minimum blood flow velocity (Vmin), maximum blood flow velocity (Vmax), mean blood flow velocity (Vmean), acceleration, resistive index and pulsatility index were measured in relation to the results of creatinine clearance, serum creatinine, blood urea nitrogen and 15 and 120 min values of the phenolsulfonphthalein test. Results: In all patients, interlobar arteries were able to be visualized and blood-flow profile was measured. Although variations of Vmin, Vmax, Vmean and acceleration were relatively large, the resistive index and pulsatility index varied little in each kidney. Mean values of Vmin (P < 0.005), Vmean (P < 0.05), resistive index (P < 0.005) and pulsatility index (P < 0.005) were well correlated to creatinine clearance with statistical significance. Conclusions: In ADPKD, color Doppler ultrasound measurement is a useful method for assessment of renal function and could be used for monitoring the dynamic state of renal blood flow as a non-invasive technique. [source] Mild Cognitive Impairment Subtypes and Vascular Dementia in Community-Dwelling Elderly People: A 3-Year Follow-Up StudyJOURNAL OF AMERICAN GERIATRICS SOCIETY, Issue 4 2006Mariella Zanetti MD OBJECTIVES: To investigate whether mild cognitive impairment (MCI) with multiple impaired cognitive domains (mcd-MCI) is a prodromal manifestation of vascular dementia (VaD). DESIGN: Prospective cohort study. SETTING: Geriatric unit of the Ospedale Maggiore Istituto di Ricovero e Cura a Carattere Scientifico, Milan, Italy. PARTICIPANTS: Four hundred community-dwelling subjects aged 65 and older who came freely to the geriatric unit as part of a comprehensive geriatric assessment program were evaluated for memory impairment or other cognitive disorders. Subjects with MCI were kept under observation for 3 years. MEASUREMENTS: Subjects with MCI were studied by applying a standardized clinical evaluation and a conducting a computed tomography brain scan. Cognitive performance was assessed using the Mini-Mental State Examination, the Clock Drawing Test, and a comprehensive battery of neuropsychological tests. Cardiovascular comorbidity was assessed on the basis of medical history and using electrocardiography, echocardiography, and carotid color Doppler ultrasound. RESULTS: MCI was found in 65 of the 400 community-dwelling subjects; 31 were classified with amnestic MCI (a-MCI) and 34 with mcd-MCI. A dysexecutive syndrome characterized people with mcd-MCI, who had significantly more vascular comorbidity and signs of vascular disease on brain imaging as well as a higher prevalence of extra pyramidal features, mood disorders, and behavioral symptoms than people with a-MCI. Twenty of the 65 subjects with MCI (31%) progressed to dementia within 3 years of follow-up: 11 subjects with Alzheimer's disease (AD) and nine with VaD. All patients who evolved to AD had been classified with a-MCI at baseline, whereas all patients who evolved to subcortical VaD had been classified with mcd-MCI at baseline. CONCLUSION: All subjects who converted to subcortical VaD had been classified with mcd-MCI, suggesting that mcd-MCI might be an early stage of subcortical VaD. [source] Comparison study of Doppler ultrasound surveillance of expanded polytetrafluoroethylene-covered stent versus bare stent in transjugular intrahepatic portosystemic shuntJOURNAL OF CLINICAL ULTRASOUND, Issue 7 2010Qian Huang MD Abstract Objective. This prospectively randomized controlled study aimed to assess with Doppler ultrasound (US) the shunt function of expanded polytetrafluoroethylene (ePTFE)-covered transjugular intrahepatic portosystemic shunt (TIPS) stent versus bare stent and to evaluate the usefulness of routine TIPS follow-up of ePTFE-covered stents. Methods. Sixty consecutive patients were randomized for bare or covered transjugular TIPS stenting in our institution between April 2007 and April 2009. Data of follow-up Doppler US, angiography, and portosystemic pressure gradient measurements were collected and analyzed. Results. The follow-up period was 8.34 ± 4.42 months in the bare-stent group and 6.16 ± 3.89 months in the covered-stent group. Baseline clinical characteristics were similar in both groups. Two hundred three US studies were performed in 60 patients, with a mean of 3.4 per patient, and demonstrated abnormalities in 28 patients (21 bare stents, 7 ePTFE-covered stents), 19 of them (13 in bare-stent group, 6 in covered-stent group) showing no clinical evidence of recurrence. Ten of 13 patients in the bare-stent group underwent balloon angioplasty or additional stent placement, whereas only one of six patients in the covered-stent group needed reintervention for intimal hyperplasia. The average peak velocity in the midshunt of ePTFE-covered stent was 139 ± 26 cm/s after TIPS creation and 125 ± 20 cm/s during follow-up, which was significantly higher than the bare-stent group (p < 0.05). The main portal vein and hepatic artery showed higher flow velocities in the ePTFE-covered stent group than in the bare-stent group. ePTFE-covered stents maintained lower portosystemic pressure gradient than bare stents (9.5 ± 2.9 versus 13.2 ± 1.5 mmHg, p < 0.05). Conclusions. ePTFE-covered stents resulted in higher patency rates and better hemodynamics than bare stents. Routine US surveillance may not be necessary in patients with ePTFE-covered TIPS stent. © 2010 Wiley Periodicals, Inc. J Clin Ultrasound 38:353-360, 2010 [source] MR-based visualization and quantification of three-dimensional flow characteristics in the portal venous systemJOURNAL OF MAGNETIC RESONANCE IMAGING, Issue 2 2010Zoran Stankovic MD Abstract Purpose: To evaluate the feasibility of time-resolved flow-sensitive MRI for the three-dimensional (3D) visualization and quantification of normal and pathological portal venous (PV) hemodynamics. Materials and Methods: Portal venous hemodynamics were evaluated in 18 healthy volunteers and 5 patients with liver cirrhosis. ECG- and adaptive respiratory navigator gated flow-sensitive 4D MRI (time-resolved 3D MRI with three-directional velocity encoding) was performed on a 3 Tesla MR system (TRIO, Siemens, Germany). Qualitative flow analysis was achieved using 3D streamlines and time-resolved particle traces originating from seven emitter planes precisely placed at anatomical landmarks in the PV system. Quantitative analysis included retrospective extraction of regional peak and mean velocities and vessel area. Results were compared with standard 2D flow-sensitive MRI and to the reference standard Doppler ultrasound. Results: Qualitative flow analysis was successfully used in the entire PV system. Venous hemodynamics in all major branches in 17 of 18 volunteers and 3 of 5 patients were reliably depicted with good interobserver agreement (kappa = 0.62). Quantitative analysis revealed no significant differences and moderate agreement for peak velocities between 3D MR and 2D MRI (r = 0.46) and Doppler ultrasound (US) (r = 0.35) and for mean velocities between 3D and 2D MRI (r = 0.41). The PV area was significantly (P < 0.01) higher in 3D and 2D MRI compared with US. Conclusion: We successfully applied 3D MR velocity mapping in the PV system, providing a detailed qualitative and quantitative analysis of normal and pathological hemodynamics. J. Magn. Reson. Imaging 2010;32:466,475. © 2010 Wiley-Liss, Inc. [source] Real-time Fourier velocity encoding: An in vivo evaluationJOURNAL OF MAGNETIC RESONANCE IMAGING, Issue 3 2005Christopher K. Macgowan PhD Abstract Purpose To compare in vivo real-time Fourier velocity encoding (FVE), spectral-Doppler ultrasound, and phase-contrast (PC) magnetic-resonance (MR) imaging. Materials and Methods In vivo velocity spectra were measured in the suprarenal and infrarenal aorta and the hepatic segment of the inferior vena cava of eight normal volunteers using FVE, and compared to similar measurements using Doppler ultrasound and gated PC MR imaging. In vivo waveforms were compared qualitatively according to flow pattern appearance (number, shape, and position of velocity peaks) and quantitatively according to peak velocity. Results Good agreement was obtained between peak velocities measured in vitro using FVE and PC MR imaging (R2 = 0.99, P = 2.10,6, slope = 0.97 ± 0.05). Qualitatively, the FVE and ultrasound measurements agreed closely in the majority of in vivo cases (excellent or good in 21/24 cases) while the PC MR method resolved fewer velocity peaks due to the inherent temporal averaging of cardiac-gated studies (excellent or good agreement with FVE in 13/24 cases). Quantitatively, the FVE measurement of peak velocity correlated strongly with both ultrasound (R2 = 0.71, P = 2.10,7, slope = 0.81 ± 0.08) and PC MR (R2 = 0.85, P = 2.10,10, slope = 1.04 ± 0.08). Conclusion Real-time MR assessment of blood-flow velocity correlated well with spectral Doppler ultrasound. Such new methods may allow hemodynamic information to be acquired in vessels inaccessible to ultrasound or in patients for whom respiratory compensation is not possible. J. Magn. Reson. Imaging 2005;21:297,304. © 2005 Wiley-Liss, Inc. [source] Who Should Be Screened for Asymptomatic Carotid Artery Stenosis?JOURNAL OF NEUROIMAGING, Issue 2 2001Experience From the Western New York Stroke Screening Program ABSTRACT Objective. Identification of significant asymptomatic carotid artery stenosis (ACAS) is important because of the stroke-risk reduction observed with carotid endarterectomy. The authors developed and validated a simple scoring system based on routinely available information to identify persons at high risk for ACAS using data collected during a community health screening program at various sites in western New York. A total of 1331 unselected volunteers without previous stroke, transient ischemic attack, or carotid artery surgery were evaluated by personal interview and duplex ultrasound. The main outcome measure was carotid artery stenosis >60% by duplex ultrasound. In the derivation set (n= 887), 4 variables were significantly associated with ACAS >60%: age >65 years (odds ratio [OR] = 4.1, 95% confidence interval [CI] = 2.6,6.7), current smoking (OR = 2.0, 95% CI = 1.2,3.5), coronary artery disease (OR = 2.4, 95% CI = 1.5,3.9), and hypercholesterolemia (OR = 1.9, 95% CI = 1.2,2.9). Three risk groups (low, intermediate, and high) were defined on the basis of total risk score assigned on the basis of the strength of association. The scheme effectively stratified the validation set (n= 444); the likelihood ratio and posttest probability for ACAS in the high-risk group were 3.0 and 35%, respectively, and in the intermediate and low-risk groups were 1.4 and 20% and 0.4 and 7%, respectively. Routinely available information can be used to identify persons in the community at high risk for ACAS. Doppler ultrasound screening in this subgroup may prove to be cost-effective and have an effect on stroke-free survival. [source] Pregnancy outcome and fibrinolytic, endothelial and coagulation markers in women undergoing uterine artery Doppler screening at 23 weeksJOURNAL OF THROMBOSIS AND HAEMOSTASIS, Issue 6 2009B. J. HUNT Summary.,Background:,Pre-eclampsia (PET) and/or fetal growth restriction (FGR) remain a major cause of maternal and fetal morbidity and mortality. In pregnancy, fibrinolysis is controlled by the maternal endothelium and placenta, both of which are central to the pathogenesis of PET/FGR. Clinically, uterine artery Doppler screening at 23 weeks is used to predict PET/FGR. An abnormal uterine artery Doppler finding is defined as early diastolic bilateral uterine artery notching (BN) in the waveform. However, about 50% of mothers with BN do not develop PET/FGR. Objectives:,We investigated fibrinolytic changes and uterine artery Doppler findings in the second trimester, and related them to pregnancy outcome; in particular assessing whether fibrinolytic markers could discriminate between normal and abnormal outcome in mothers with BN. Patients/methods:,Plasma levels of tissue-type plasminogen activator (t-PA), plasminogen activator inhibitor-1 (PAI-1), plasminogen activator inhibitor-2 (PAI-2), plasmin-,2 antiplasmin (PAP), D-dimers and markers of endothelial dysfunction were measured with Doppler ultrasound at 23 weeks. Results:,Those with BN had decreased PAP and D-dimer levels, and raised PAI-1 and thrombomodulin levels. Mothers with BN and PET/FGR had significantly increased t-PA levels and reduced PAI-2 levels. Conclusions:,BN at 23 weeks of gestation is associated with increased PAI-1 levels. Within the BN group, mothers who developed PET/FGR had increased t-PA levels and decreased PAI-2 levels, although there was no net change in fibrinolysis as measured by D-dimer levels. No single fibrinolytic marker is helpful in determining pregnancy outcome in those with BN, but t-PA and PAI-2 are worthy of study in a multifactorial algorithm. [source] Transesophageal monitoring of aortic blood flow during nonemergent canine surgeriesJOURNAL OF VETERINARY EMERGENCY AND CRITICAL CARE, Issue 1 2002Piper L. Wall Abstract Objective: To establish baseline values for descending thoracic aortic blood flow parameters as determined with a transesophageal combined M-mode and pulsed Doppler ultrasound-based monitoring method. Design: Preliminary observational study. Setting: University small animal teaching hospital. Animals: The study population consisted of anesthetized canine patients undergoing nonemergent surgeries. Prospectively set criteria for inclusion were adequate body size for placement of the esophageal probe and a nonemergent reason for surgery. The criterion for exclusion was recent trauma. Interventions: Placement of the transesophageal probe. Measurements and main results: Data was collected during 15 surgeries. Data from three dogs was excluded from data analysis (two recently hit by motor vehicles, one recently having undergone a total hip replacement). Each parameter was stable across time within each individual dog. The ranges of the descending thoracic aortic parameters across the 12 nonemergent cases were as follows: blood flow, 0.038,0.085 L min,1 kg,1; blood flow per beat, 0.31,0.84 mL kg,1; blood acceleration, 6,29 m s2,1; blood peak velocity, 38,105 m s,1; left ventricular ejection time interval 331,492 ms; and diameter, 0.30,0.93 mm kg,1. Conclusions: The range of descending thoracic aortic blood flow parameters encountered in this small group of dogs during nonemergent surgeries was broad; however, each parameter was quite stable across time with little change occurring in any dog during monitoring. [source] Performance of Doppler ultrasound in the prediction of severe portal hypertension in hepatitis C virus-related chronic liver diseaseLIVER INTERNATIONAL, Issue 10 2007Francesco Vizzutti Abstract Purpose: To evaluate the correlation between hepatic vein pressure gradient measurement and Doppler ultrasonography (DUS) in patients with chronic liver disease (CLD). Patients and methods: Sixty-six patients with fibrotic to cirrhotic hepatitis C virus-related CLD, were consecutively included upon referral to our haemodynamic laboratory. Superior mesenteric artery pulsatility index (SMA-PI), right interlobar renal and intraparenchymal splenic artery resistance indices, were determined, followed by hepatic venous pressure gradient (HVPG) measurement. Results: A correlation was found between HVPG and intraparenchymal splenic artery resistance index (SA-RI) (r=0.50, P<0.0001), SMA-PI (r=,0,48, P<0.0001), right interlobar renal artery resistance index (RRA-RI) (r=0.51, P<0.0001) in the whole patient population. However, dividing patients according to the presence/absence of severe portal hypertension (i.e. HVPG ,12 mmHg), a correlation between HVPG and intraparenchymal SA-RI (r=0.70, P<0.0001), SMA-PI (r=,0.49, P=0.02), RRA-RI (r=0.66, P=0.0002) was observed only for HVPG values <12 mmHg. HVPG but not DUS correlated with the presence of esophageal varices (P<0.0001). Conclusions: Superior mesenteric artery pulsatility index, intraparenchymal splenic and right interlobar renal artery resistance indices do not adequately predict severe portal hypertension. [source] Octreotide in liver cirrhosis: a salvage for variceal bleeding can be a gunshot for kidneysLIVER INTERNATIONAL, Issue 3 2005Deniz Güney Duman Abstract Background: The renal effects of octreotide, used for bleeding esophageal varices in cirrhosis, are controversial. Methods: Fourteen cirrhotic patients (Child,Pugh; A/B/C: 1/12/1) were enrolled. Plasma nitrite and endothelin (ET) levels, urinary nitrite output, free water clearance (FWC) and fractional excretion of filtered sodium (FENa) were measured and renal Doppler ultrasound was carried out. Octreotide was infused at a rate of 0.75 ,g/kg/h for 3 h after a bolus of 0.75 ,g/kg body weight. All the parameters were reevaluated during octreotide administration while the patients acted as their own controls. Results: Octreotide induced significant reductions in urinary nitrite, FENa and FWC. Plasma ET levels increased (baseline: 6.7 pg/ml, octreotide: 8.4 pg/ml), whereas the plasma nitrite level did not change significantly after octreotide infusion. Overall, no significant change in renal resistive index (RRI) could be demonstrated on Doppler after octreotide administration. However, patients with elevated baseline RRI values had significantly more deterioration in FWC and FENa compared with patients with normal RRI in response to octreotide. Conclusion: A marked decrease in FENa, FWC and urinary nitrite output, together with a significant increase in plasma ET level in response to octreotide, may indicate renal dysfunction in cirrhotic patients. This deleterious renal effect of octreotide may be more enhanced in patients with elevated baseline RRI. [source] Balloon dilatation vs. balloon dilatation plus bile duct endoprostheses for treatment of anastomotic biliary strictures after liver transplantationLIVER TRANSPLANTATION, Issue 1 2006Thomas Zoepf Biliary strictures after liver transplantation are a therapeutic challenge for endoscopy. Anastomotic strictures occur in 10% of patients after liver transplantation, leading untreated to mortality and ultimately to graft failure. Despite of successful reports, to date, there is no defined endoscopic therapy regimen for these cases. Therefore the aim of this study was to determine the most suitable concept for endoscopic treatment of post-liver transplant anastomotic strictures (PTAS). A total of 72 patients post-liver transplantation, who received endoscopic retrograde cholangiography (ERC) as a consequence of suspected biliary complications were retrospectively screened for the presence of PTAS. In all patients graft rejection or bile duct ischemia were excluded prior to ERC by liver biopsy or Doppler ultrasound respectively. We compared either balloon dilatation (BD) alone or dilatation plus placement of an increasing number of bile duct endoprostheses (BD + endoprostheses) in a retrospective analysis. A total of 25 of 75 patients showed PTAS. Overall, endoscopic therapy was successful in 22 of 25 patients (88%). BD was initially successful in 89% but showed recurrence in 62%. BD + endoprostheses was initially successful in 87%, and recurrence was observed only in 31%. All recurrences were successfully retreated by BD + endoprostheses. During 22 of 109 (20%) treatment sessions stone extraction was necessary. Complication rate was low with bacterial cholangitis in 8 of 109 (7.3%) sessions, mild pancreatitis in 10 of 109 (9%) sessions and minor bleeding in 2 of 25 (8%) sphincterotomies. Median follow-up after conclusion of endoscopic therapy is 6 months (range 1,43). In conclusion, our data confirm that endoscopic therapy of PTAS is highly effective and safe. As primarily successful BD shows a high rate of recurrence, we recommend a combination of BD followed by an increasing number and diameter of endoprostheses. Therapy sessions are effective at short intervals of every 2,3 months. Liver Transpl 12:88,94, 2006. © 2005 AASLD. [source] Rapid quantitation of cardiovascular flow using slice-selective fourier velocity encoding with spiral readoutsMAGNETIC RESONANCE IN MEDICINE, Issue 4 2007Joao L. A. Carvalho Abstract Accurate flow visualization and quantitation is important for the assessment of many cardiovascular conditions such as valvular stenosis and regurgitation. Phase contrast based methods experience partial volume artifacts when flow is highly localized, complex and/or turbulent. Fourier velocity encoding (FVE) avoids such problems by resolving the full velocity distribution within each voxel. This work proposes the use of slice selective FVE with spiral readouts to acquire fully localized velocity distributions in a short breath-hold. Scan-plane prescription is performed using classic protocols, and an automatic algorithm is used for in-plane localization of the flow. Time and spatially-resolved aortic valve velocity distributions with 26-msec temporal resolution and 25 cm/sec velocity resolution over a 600 cm/sec field-of-view were acquired in a 12-heartbeat breath-hold. In carotid studies, scan time was extended to achieve higher spatial resolution. The method was demonstrated in healthy volunteers and patients, and the results compared qualitatively well with Doppler ultrasound. Acquisition time could be reduced to 7 heartbeats (a 42% reduction) using partial Fourier reconstruction along the velocity dimension. Magn Reson Med 57:639,646, 2007. © 2007 Wiley-Liss, Inc. [source] | |||||||||||||||||||||||||||||||||||||