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Selected AbstractsEvaluation of the hepatic artery anastomosis by intraoperative sonography with high-frequency transducer in right-lobe graft living donor liver transplantationJOURNAL OF CLINICAL ULTRASOUND, Issue 1 2010Han Song Mun MD Abstract Objective To describe the usefulness of intraoperative ultrasonography (IOUS) with high-frequency transducer in living donor liver transplantation (LDLT) using right-lobe graft (RLG). Method This retrospective study was approved by our institutional review board. We performed IOUS in 22 patients (17 men and 5 women, aged 51 ± 9.0 years) during LDLT with RLG using a Sequoia 512 scanner with an 8,12-MHz linear transducer. Hepatic artery (HA) anastomosis was identified on gray-scale US, and the diameter and percentage of stenosis of the anastomosis were measured. The HA was evaluated to detect thrombus or dissection in the region of anastomosis. Doppler study of the graft HA was also performed. Patients were divided into those with and without abnormalities, including thrombosis, dissection, and abnormal Doppler parameters (peak systolic velocity < 30 cm/s or > 2 m/s, resistance index < 0.5, and systolic acceleration time > 80 msec). Result On gray-scale and Doppler IOUS study, abnormalities were found in 10 of 22 patients. Diagnoses were anastomotic stenosis (n = 2), celiac stenosis (n = 1), compromise of HA inflow due to systemic hypotension (n = 1), HA thrombosis (n = 2), and HA dissection (n = 4). Re-anastomoses were done in 3 case (2 stenoses and 1 thrombosis). Uneventful postoperative recovery occurred in the other 7 patients without re-anastomosis. Conclusion IOUS with high-frequency transducer is a useful method to make an early diagnosis of HA complications of LDLT with RLG. © 2009 Wiley Periodicals, Inc. J Clin Ultrasound, 2010 [source] Routine intraoperative Doppler sonography in the evaluation of complications after living-related donor liver transplantationJOURNAL OF CLINICAL ULTRASOUND, Issue 9 2007Jin-Young Choi MD Abstract Purpose To determine whether quantitative and qualitative analysis of intraoperative Doppler sonography data are predictive of vascular complications after living-related donor liver transplantation. Methods Intraoperative sonograms of 81 transplanted livers (right lobe in 61 patients, left lobe in 20 patients) were analyzed for the presence of blood flow, resistance index, systolic acceleration time (SAT), peak systolic velocity, and morphologic characteristics of spectral waveform of the hepatic artery. Peak velocity and spectral waveforms of portal and hepatic veins were also analyzed. Intraoperative sonography results were compared with information obtained with multidetector-row CT (MDCT) angiography or conventional angiography. The time interval between operation and angiography ranged from 1 to 23 days (mean, 8.5 days). Results Hepatic artery stenosis (HAS) was identified in 20 patients via MDCT angiography, conventional angiography, or both. The Doppler parameters found helpful for predicting HAS were tardus-parvus pattern and delayed SAT. The sensitivity, specificity, and negative predictive value (NPV) were 60.0%, 73.7%, and 84.9%, respectively, for tardus-parvus pattern and 40.0%, 83.6%, and 80.9%, respectively, for delayed SAT. Peak velocities of the portal and hepatic veins were not reliable indicators of vascular complication. Loss of triphasity of the hepatic vein had a 98.4% NPV for venous obstruction. Conclusions Delayed SAT of the hepatic artery and loss of triphasity of the hepatic vein had a >80% for specificity for predicting vascular complications. Tardus-parvus pattern, delayed SAT of the hepatic artery, and loss of triphasity of the hepatic vein showed an acceptable NPV for identifying vascular complications. © 2007 Wiley Periodicals, Inc. J Clin Ultrasound, 2007 [source] Duplex Doppler sonography of transplant renal artery stenosisJOURNAL OF CLINICAL ULTRASOUND, Issue 3 2003Ruth Helena de Morais MD Abstract Purpose The aim of this study was to evaluate the accuracy of duplex Doppler sonography in diagnosing transplant renal artery stenosis (TRAS) and to determine which parameter is the most reliable for making that diagnosis. Methods Over a 3-year period, we sonographically evaluated patients who were referred for investigation of possible TRAS. We investigated the following parameters: peak systolic velocity (PSV) in the external iliac and renal arteries, acceleration time and acceleration in the intrarenal arteries, acceleration time in the renal artery, resistance index, and the ratio of the PSVs in the renal and external iliac arteries. We also used MR angiography and digital subtraction arteriography to verify the degree of stenosis. After the evaluations, the patients were classified into 2 groups, 1 with and the other without significant stenosis (> 50% narrowing of the lumen) on digital subtraction arteriography. We also included a control group of patients who had undergone renal transplantation at least 6 months before, had had a good course after transplantation, had a diastolic blood pressure of 90 mm Hg or less, and were taking a maximum of 1 antihypertensive drug. Results Our study population consisted of 22 patients suspected to have TRAS (10 without and 12 with confirmed significant stenosis) and 19 control patients. We found statistically significant differences between the mean values of these 3 groups except for the PSV in the iliac artery and the resistance index in the intrarenal arteries. The most accurate parameters to use in diagnosing TRAS were an acceleration time of 0.1 second or higher in the renal and intrarenal arteries, a PSV of greater than 200 cm/second in the renal artery, and a ratio of PSVs in the renal and external iliac arteries of greater than 1.8. Conclusions Duplex Doppler sonography is an excellent method for screening patients suspected to have TRAS and can help select which of those patients should undergo digital subtraction arteriography. © 2003 Wiley Periodicals, Inc. J Clin Ultrasound 31:135,141, 2003 [source] Observer experience improves reproducibility of color doppler sonography of orbital blood vesselsJOURNAL OF CLINICAL ULTRASOUND, Issue 6 2002János Németh MD Abstract Purpose. The study investigated the reproducibility of orbital blood flow measurements with color Doppler imaging (CDI) at different stages of observer experience. Methods. The subjects were 31 healthy volunteers and 2 sequential groups of 25 glaucoma patients each. Repeated blood flow measurements (usually 3 sets) in orbital vessels (ophthalmic artery, short posterior ciliary arteries, central retinal artery, and central retinal vein) were performed by the same observer in a single session in each subject. Results. The parameters with the best reproducibility were the resistance index (mean coefficient of variation [COV], 3.3,8.8%), the peak systolic velocity (mean COV, 6.9,13.7%), the time-averaged velocity (mean COV, 7.2,16.0%), and the systolic acceleration time (mean COV, 8.8,12.3%). The mean COV was greater (9.9,20.3%) for the other arterial flow parameters (end-diastolic velocity and systolic acceleration) and for the venous flow velocities (maximum and minimum). The COVs of the parameters were improved by 20,40% as the observer became more experienced in ophthalmic CDI. Conclusions. We confirm the general reliability of CDI measurements in orbital vessels and show that observer experience improves reproducibility. It appears, however, that observer performance in these measurements is vessel specific. © 2002 Wiley Periodicals, Inc. J Clin Ultrasound 30:332,335, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI: 10.1002/jcu.10079 [source] Doppler velocimetry of maternal renal circulation in pregnancy-induced hypertensionJOURNAL OF CLINICAL ULTRASOUND, Issue 8 2001Hidehiko Miyake MD Abstract Purpose The purpose of this study was to evaluate whether the Doppler waveforms of the maternal main renal, segmental, and interlobar arteries are altered in women with pregnancy-induced hypertension (PIH) compared with healthy pregnant women. Methods Flow waveforms of the maternal main renal, segmental, and interlobar arteries were obtained from 42 healthy pregnant women between 24 and 41 weeks of gestation and 21 women with PIH between 28 and 40 weeks of gestation using pulsed Doppler sonography. We used spectral analysis to measure the peak systolic and end-diastolic velocities and the acceleration time. The presence or absence of the normal early systolic compliance peak-reflective-wave complex (ESP) was assessed in only the main renal artery. Results The acceleration times of the segmental and interlobar arteries were significantly prolonged in the PIH group compared with those in the healthy pregnant women. Of the 21 women with PIH, 3 showed loss of the ESP in the renal artery, but these changes were not significant. Conclusions Decreased systolic acceleration and the absence of ESP, the hemodynamic indicators for significant proximal stenosis, suggest that severe stenosis or continuous vasospasm in the proximal arteries, such as the main renal or segmental artery, may be implicated in the pathogenesis of PIH. © 2001 John Wiley & Sons, Inc. J Clin Ultrasound 29:449,455, 2001. [source] Assessment of right ventricular diastolic filling parameters by Doppler echocardiographyPEDIATRICS INTERNATIONAL, Issue 3 2003Ayten Pamukcu Uyan AbstractBackground: Right ventricular diastolic function has been evaluated in various diseases by the pulsed Doppler technique. Right ventricular diastolic filling parameters show changes with age, heart rate and respiration. Evidences of diastolic left and right ventricular dysfunctions have been reported by echocardiographic studies in asthmatic patients. In the present study, before and after treatment of asthma the right ventricular diastolic filling parameters were compared in children with moderate asthma by Doppler echocardiography (a non-invasive technique). Methods: The study group consisted of 20 children (eight girls, 12 boys) with asthma. During the present study these patients were treated with inhaled steroid and beta-2 agonist daily. Before treatment all patients were evaluated by Doppler echocardiography. At 4,6 weeks after treatment 15 patients that had shown improvement in their symptoms according to the symptom score were also evaluated by Doppler echocardiography. Results: The mean age was 8.6 ± 2.69 years and mean period of symptoms were 56.4 ± 35.8 months. When compared with results of echocardiography before and after treatment, the right ventricular diastolic filling parameters (acceleration time: P < 0.01, deceleration time: P < 0.01 and isovolumetric relaxation time: P < 0.05) were found to be significantly different. Conclusions: We observed significant improvement of right ventricular diastolic filling parameters by Doppler echocardiography after treatment in children with asthma. [source] | ||||||||||