Sensitivity Of Doppler Ultrasound Research Articles

Role of doppler ultrasound in detecting vascular complications in recipients of living donor liver transplant (LDLT).

To determine the role of Doppler ultrasound in the detection of vascular complications in recipients of living donor liver transplant, keeping contrast-enhanced computerised tomography of abdomen as the gold standard. The retrospective study was conducted from February 16 to April 1, 2022, at the Pakistan Kidney and Liver Institute and Research Centre, Lahore, Pakistan, and comprised data of living donor liver transplant recipients who had undergone contrast-enhanced computerised tomography of abdomen within 24 hours of Doppler ultrasound between January 2021 and January 2022. For the diagnosis of hepatic vascular complications, the diagnostic values of Doppler ultrasound parameters were derived by correlating Doppler ultrasound findings with contrast-enhanced computerised tomography results. Data was analysed using SPSS 20. Of the 35 patients, 24(68.6%) were men and 11(31.4%) were women. The overall mean age was 45.86±13.8 years. For hepatic artery thrombosis, the use of Doppler ultrasound criteria yielded a sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of 100%, 96.6%, 83.3%, 100%, and 97.1% respectively. For hepatic artery stenosis, overall sensitivity, specificity, positive predictive value, negative predictive value and accuracy of Doppler ultrasound was 100%, 96.8%, 75%, 100% and 97.1% respectively. Doppler ultrasound parameters resulted in a sensitivity, specificity, positive predictive value, negative predictive value and accuracy of 100% each in detecting portal vein and hepatic venous outflow tract thrombosis. Overall, Doppler ultrasound sensitivity, specificity, positive predictive value, negative predictive value and diagnostic accuracy was found to be 100%, 88.8%, 89.4%, 100% and 94.2% respectively. Doppler ultrasound was adequate to document vascular complications after living donor liver transplant in majority of the cases with high accuracy and sensitivity.

Sensitivity and Specificity of Color Duplex Ultrasound Measurement in the Estimation of Internal Carotid Artery Stenosis

Background: Stroke is that the world's leading reason for death and major incapacity. Arterial sclerosis is answerable for over half-hour of all ischemic strokes. Plaque morphology has recently been discovered to assist within the prediction of arterial sclerosis clinical behavior and stroke risk. Purpose: The goal of this study was to gauge the frequency and diagnostic exactitude of artery Doppler imaging to detect arterial blood vessel pathology. Methods: This cross-sectional study was conducted in Combined Military Hospital, Peshawar from1st August 2019 to 31st March 2020. A total of 120 patients were randomly selected. The inclusion criteria was having ischemic cerebrovascular stroke. Doppler ultrasound was performed in every patient by a consultant radiologist. Doppler ultrasound findings were compared with Carotid artery stenosis reports. Results: Mean age in this study was 63.07±3.76 years. Mean duration of disease was 1 year ±3.32 months. Overall sensitivity, specificity, positive predictive value, negative predictive value and diagnostic accuracy of Doppler Ultrasound were 89.5, 76.20, 45.5, 93.88 and 76.9% respectively. The areas under the ROC curves ranged between 0.89 and 0.90 for the laboratory A device and between 0.90 and 0.92 for the laboratory B device. In laboratories A and B, the areas under the ROC curves for ICA PSV were 0.90 and 0.92, respectively. Similar effects were observed when occlusion-affected patients were omitted (0.89 to 0.91, laboratory A; 0.90 to 0.93, laboratory B). Despite the fact that the diagnostic accuracy of the two devices was equivalent, two points on the ROC curves corresponding to the same cut point were infrequently near. Practical implication: The study compared the techniques of Doppler ultrasound for the diagnosis of carotid artery stenosis in patients and measured the best predicted percent angiographic stenosis differed between two vascular laboratories and paved the way for clinicians to focus of the diagnosis of carotid artery stenosis by DU. Conclusion: With the advancement in technology, the accuracy of carotid artery stenosis diagnosis has significantly improved over the decades. From measuring the narrowing carotid artery diameter to evaluating the increased velocity field near the obstruction/lesion site, the identification of additional parameters to characterize plaque vulnerability has become more important in the carotid artery. Keywords: Angiography; Carotid artery stenosis; Cerebrovascular ischemia; Doppler ultrasound sensitivity.

Validity of Carotid Doppler Ultrasound for Detection of Carotid Artery Plaque Keeping Computed Tomography Sensitivity as Reference Standard

Objective: To determine the prevalence and specificity of arterial Doppler imaging pathology identification of artery blood vascular disease Study Design: Cross-sectional Place and Duration: In the department of Radiology, Peshawar Institute of Cardiology MTI, Peshawar for the duration from January 2022 to May 2022. Methods: Total 95 patients of both genders were presented. All the patients were suffering from ischemic cerebrovascular illness. Informed written consent of all the patients were taken for detailed demographics. Doppler ultrasound was performed in every patient by a consultant radiologist. Doppler ultrasound findings were compared with Carotid artery stenosis reports. SPSS 20.0 was used to analyze all data. Results: The mean age of the patients was 52.11±8.40 years and had mean BMI 24.1±13.25 kg/m2. The mean duration of disease was 1.7±6.34 years. 52 (54.7%) were males and 43 (45.3%) were females. There were 56 (58.9%) cases were smokers. Comorbidities were diabetes mellitus, ischemic heart disease, hypertension, ischemic stroke and dyslipidemia. Doppler ultrasound has a 91% overall sensitivity, 77% specificity, 47.3% positive predictive value, 92.5% negative predictive value, and 80% diagnostic accuracy. Conclusion: The accuracy of diagnosing Carotid artery stenosis has greatly increased over time because to technological innovation. The finding of additional measures to describe plaque susceptibility in the carotid artery has grown in importance, from monitoring the carotid artery's shrinking diameter to assessing the enhanced velocity field close to the obstruction/lesion site. The sensitivity, precision, and reliability of Artery stenosis diagnosis have improved because to computer-aided programmes used in a variety of imaging modalities. Keywords: Specificity, Carotid artery stenosis, Doppler ultrasound Sensitivity

Validity of Carotid Doppler Ultrasound for Detection of Caroted Stenosis keeping Computed Tomography Sensitivity as Gold Standard

Background: Stroke is that the world's leading reason for death and major incapacity. Arterial sclerosis is answerable for over half of all ischemic strokes. Plaque morphology has recently been discovered to assist within the prediction of arterial sclerosis, Clinical behaviour and stroke risk.Objective: To guage the frequency and diagnostic exactitude of artery Doppler imaging pathology detection to arterial blood vessel pathology.Material and Methods: Study was conducted in Combined Military Hospital, Peshawar from1st August 2019 to 31st March 2020. A total of 120 patients were consecutively selected. The inclusion criteria were all the patients having ischemic cerebrovascular disease. Doppler ultrasound was performed in every patient by a consultant radiologist. Doppler ultrasound findings were compared with Carotid artery stenosis reports.Results: Age range in this study was from 30-80 years with mean age of 63.07±3.76 years. Mean duration of disease was 1 Years ±3.32 months. Overall sensitivity, specificity, positive predictive value, negative predictive value and diagnostic accuracy of Doppler Ultrasoundis 89.5%, 76.20%, 45.5%, 93.88% and 76.9% respectively.Conclusion: With the advancement in technology, the accuracy of Carotid artery stenosis diagnosis has significantly improved over the decades. From measuring the narrowing carotid artery diameter to evaluating the increased velocity field near the obstruction/lesion site, the identification of additional parameters to characterize plaque vulnerability has become more important in the carotid artery. Via various imaging modalities, the use of computer-aided programmes has increased the sensitivity, precision, and accuracy of Carotid artery stenosis diagnosis.Key Words: Carotid artery stenosis, Doppler ultrasound Sensitivity, Specificity

Aspectos clínicos e ultra-sonográficos de pacientes com câncer e suspeita de trombose venosa profunda

To evaluate Doppler Ultrasound (DUS) in oncology patients suspected of having Deep Venous Thrombosis (DVT) and correlate findings with their clinical characteristics and outcome. A study was made with 96 consecutive oncology patients submitted to DUS suspected to have DVT between May 2001 and April 2002. The same radiologist examined 73 women and 23 men, with a median age of 58 years, using DUS equipment, with high frequency linear and convex probes (logic500--GE and HDI5000--Philips). In 42 (43.8%) patients the DUS was considered normal, in 33 (34.4%) DVT was diagnosed and 21 of them had superficial or previous deep venous thrombosis or non conclusive studies. Considering clinical evaluation (and death by PE as caused by DVT) as the gold standard, DUS sensitivity was of 95.9%. There was a statistically significant correlation between DVT and tumor stage at the time of initial diagnosis and patient's survival rate (p<0.05). There was no correlation between DVT and gender, age, type of malignancy, stage of disease at the time of DVT diagnosis and different treatment regimens. It was concluded that in cancer patients DUS has a high sensitivity for diagnosis of DVT and that DVT diagnosis in these patients correlates with a shorter overall survival. Since there are no reliable clinical predictors to identify cancer patients with DVT, DUS should be performed whenever DVT is suspected.

Amplitude Doppler US: slow blood flow detection tested with a flow phantom.

To evaluate the in vitro sensitivity for the detection of slow blood flow in tiny tubes with an amplitude Doppler ultrasound (US) technique at different angles and pulse repetition frequencies. Human blood treated with heparin was pumped through silicone tubes (flow phantoms made by the author) with lumina of 3.00 mm, 0.30 mm, and 0.05 mm. Slow flow was imaged by using amplitude and color Doppler US techniques with two US devices at different pulse repetition frequencies and angles and in different sound propagation media. Under ideal conditions, the lowest detectable velocity was 0.04-0.06 cm/sec in the 3.00-mm tube. Detection was about three to four times less sensitive in the 0.30-mm and 0.05-mm tubes. Amplitude Doppler US sensitivity is only slightly dependent on the angle of incidence and propagation medium. The fractional volume flow determined the sensitivity of the amplitude Doppler technique for detecting low flow. Amplitude Doppler US is nearly angle independent; thus, it is superior to color Doppler US. Amplitude Doppler US is three to four times more sensitive when tube have very tiny lumina and when probes of a lower frequency are used.

Cost-effectiveness of screening for asymptomatic carotid atherosclerotic disease.

The value of screening for asymptomatic carotid stenosis has become an important issue with the recently reported beneficial effect of endarterectomy. The purpose of this study is to evaluate the cost-effectiveness of using Doppler ultrasound as a screening tool to select subjects for arteriography and subsequent surgery. A computer model was developed to simulate the cost-effectiveness of screening a cohort of 1000 men during a 20-year period. The primary outcome measure was incremental present-value dollar expenditures for screening and treatment per incremental present-value quality-adjusted life-year (QALY) saved. Estimates of disease prevalence and arteriographic and surgical complication rates were obtained from the literature. Probabilities of stroke and death with surgical and medical treatment were obtained from published clinical trials. Doppler ultrasound sensitivity and specificity were obtained through review of local experience. Estimates of costs were obtained from local Medicare reimbursement data. A one-time screening program of a population with a high prevalence (20%) of > or = 60% stenosis cost $35130 per incremental QALY gained. Decreased surgical benefit or increased annual discount rate was detrimental, resulting in lost QALYs. Annual screening cost $457773 per incremental QALY gained. In a low-prevalence (4%) population, one-time screening cost $52588 per QALY gained, while annual screening was detrimental. The cost-effectiveness of a one-time screening program for an asymptomatic population with a high prevalence of carotid stenosis may be cost-effective. Annual screening is detrimental. The most sensitive variables in this simulation model were long-term stroke risk reduction after surgery and annual discount rate for accumulated costs and QALYs.

Renal Transplant Rejection

Over a two-year period, 275 duplex Doppler ultrasound (US) examinations were performed on 75 renal allograft recipients. Retrospective visual analysis of the Doppler tracings was compared to concurrent clinical findings and to biopsy results. One hundred eight of the 176 Doppler examinations (61%) that showed acute rejection clinically or histologically were interpreted as rejection, while 80 of 99 examinations (81%) in clinically normal patients were interpreted as normal. Two hundred thirty-four examinations had resistive index (RI) calculations. Seventy-two of 141 examinations (51%) with RI less than 0.70 had clinical or biopsy evidence of rejection. Studies compared with only concurrent biopsies revealed that 35 of 39 US examinations interpreted as rejection were confirmed histologically, but only one of 32 examinations that appeared normal sonographically was histologically normal. The low sensitivity of Doppler US, whether by waveform analysis or RI calculation, makes it a poor screening test for acute rejection. The findings support the conclusion that Doppler sonography cannot replace biopsy in the evaluation of renal transplant dysfunction, particularly when the waveform analysis is normal and the RI less than 0.70.