Doppler Sonography In Detection Research Articles

Sickle Cell Disease in Children: Accuracy of Imaging Transcranial Doppler Ultrasonography in Detection of Intracranial Arterial Stenosis

This study aimed to determine the accuracy of imaging transcranial Doppler sonography in detection of intracranial arterial stenosis in children with sickle cell disease using three-dimensional MR angiography as a reference standard. Sixty-one children (mean age 102±39 months, 30 males), who had no history of overt stroke, and were classified as at lowest risk of stroke by mean flow velocity criterion <170 cm/s, underwent conventional and imaging transcranial Doppler ultrasonographic examinations. We employed the area under the receiver operating characteristic curve (AUC) to determine the accuracy of flow velocity measurements obtained with imaging ultrasonography with and without correction for the angle of insonation as well as with conventional ultrasonography. We also established the most efficacious velocity thresholds for detection of the stenosis. We found ten intracranial stenoses in six patients on MR angiography, but we calculated AUC only for detection of stenosis (n=6) of the left intracranial internal carotid artery. The accuracy of flow velocity with angle correction was lower than the accuracy of velocity without angle correction (AUC=0.73, 95% CI, 0.53-0.93 versus AUC=0.87, 95% CI, 0.74-1.00; p=0.017). The accuracy of flow velocity obtained with conventional ultrasonography (AUC=0.82, 95% CI, 0.67-0.97) was not different from the accuracy of flow velocities obtained with imaging ultrasonography. We found that the threshold of 165 cm/s of mean velocity without angle correction is associated with highest efficiency for imaging (92%) and conventional ultrasonography (90%). Velocity measurements without angle-correction provide good accuracy in detection of stenosis of the terminal internal carotid artery, whereas angle-corrected velocities have lower accuracy.

Serum and Urinary Nitrites and Nitrates and Doppler Sonography in Detection of Early Diabetic Complications

Objective: to evaluate serum and urinary nitrite and nitrate concentrations as an index of nitric oxide (NO) production in type1diabetes mellitus (T1DM) and to investigate the possible alteration and correlation with intra renal Doppler resistive indexes (RIs). Design: The study included 90 children and adolescent with T1DM divided into 2 groups: Group 1: included 45 prepubertal type1 diabetics who were defined as Tanner stage1. Their age ranged between 8-14 years. Group 2: included 45 pubertal type diabetics who were defined as Tanner stages 2-5. Their ages ranged between 15-19 years. They were compared to 45 age and sex matched healthy controls. Clinical examination was done. Laboratory investigations included; post-prandial blood glucose (PPBG), glycosylated heamoglobin (HbA1C), Fundus examination, urinary microalbumin and measurement of serum and urinary nitrite and nitrate levels. Doppler ultrasonographic registration of intrarenal RIs were performed. Results: Compared to controls, both diabetic groups had significantly increased concentrations of serum (P=0.001) and urinary NO (P=0.008).Doppler RIs values were significantly elevated in both diabetic groups compared to controls (P<0.001).A significant positive correlation was found between serum and urinary NO levels (P<0.001). Serum NO was positively correlated with Doppler RIs (P=0.002), HbA1c (P=0.012), PPBG (P=0.000) and diabetes duration (P=0.004). Doppler RIs were positively correlated with mean HbA1c (P=0.025), PPBG (P=0.001) and diabetes duration (P=0.000). Conclusion: In type 1 diabetes chronic hyperglycemia may act through a mechanism that involves increased NO production or action and contributes to generating intrarenal hemodynamic abnormalities which could be detectable by Doppler ultrasonography even before overt clinical nephropathy. Further follow up studies are needed to document the usefulness of Doppler ultrasound in detection of preclinical nephropathy.

Power Doppler sonography for detection of intraarticular vascularization in knee joints of patients with rheumatoid arthritis

A series of 47 knee joints in 24 patients with rheumatoid arthritis were examined for intraarticular vascularization by power Doppler sonography. The intensity of vascularization was compared with the synovial effusion and proliferation evaluated by gray-scale sonography and the clinical findings in the patients. Vascularization was graded from 0 to 3 by counting the number of color-flow signals: grade 0, no signals; grade one, 1–4 signals; grade two, 5–8 signals; grade three, 9 or more signals. The grade of vascularization correlated with the grade of synovial effusion (P ≪ 0.01), the grade of synovial proliferation (P ≪ 0.05), and the serum levels of C-reactive protein (P ≪ 0.05). It correlated inversely with disease duration (P ≪ 0.01). Consistent with improvement of articular inflammation, a decrease in the number of color-flow signals was observed in two patients. Power Doppler sonography is suitable for evaluating the intensity of synovitis and for monitoring the clinical activity of rheumatoid patients.

Investigation of vesicoureteral reflux with colour Doppler sonography in adult patients with spinal cord injury

The aim of the study was to evaluate prospectively the performances of colour Doppler sonography for detection of vesicoureteral reflux in adult patients with neurogenic bladder due to spinal cord injury. One hundred eighty-seven adult patients who had developed neurogenic bladder due to spinal cord injury underwent retrograde cystography and sonographic evaluation by B-mode and colour flow Doppler sonography (CFDS). Results of both examinations were analyzed independently by two radiologists. Representative images of the sonographic evaluations were recorded on videotape and CD-Rom. CFDS detected reflux in 20 ureters while retrograde cystography revealed vesicoureteral reflux (VUR) in 25 ureters of a total of 374 ureters, which were examined by both methods. Sonography detected all cases of grades IV and V of reflux, 7 of 8 (87.5%) of grade III, 5 of 6 (83.3%) of grade II, and 4 of 7 (57.14%) of grade I. There were 6 false-positive and 5 false-negative findings with Doppler examination compared with retrograde cystography. Therefore, sensitivity and specificity of sonographic examination were 80 and 98.28%, respectively, with a positive predictive value of 76.92%. Colour flow Doppler sonography can play an important role in detection of VUR in spinally injured adult patients with neurogenic bladder and can be an effective imaging tool for follow-up.

Use of color Doppler sonography for detection of thyroid nodules.

Use of color Doppler sonography for detection of thyroid nodules.

Validity of continuous-wave Doppler sonography of the vertebrobasilar system.

To assess the value of continuous-wave Doppler sonography for detection and exclusion of lesions in the vertebrobasilar system, the ultrasonic and angiographic findings were compared in a prospective study. Altogether, 200 vertebral arteries in 176 patients were evaluated by both methods. Insonation of the vertebral arteries was performed at the mastoid slope and at the origin of the vessel. Of 62 angiographically proven lesions, 45 were detected by ultrasound. Of 138 normal vertebral arteries, 129 were correctly diagnosed. Sensitivity for all lesions was 72.5%, and for hemodynamically relevant lesions it was 91%. Overall specificity was 93.5%. A positive predictive value of 83.3% and a negative predictive value of 88.4% for all lesions shown by angiography demonstrate the high reliability and accuracy of doppler ultrasound of the vertebrobasilar system.