ABSTRACT
An 80-year-old female patient with arterial hypertension and slowly progressive deterioration of renal function was referred to our department for investigation of the renal arteries. Imaging of the renal arteries with ultrasound was inconclusive, due to obesity. Subsequently, imaging was performed with balanced turbo field echo which is a newly developed technique in our department. This new technique for the moment is still combined with contrast-enhanced magnetic resonance angiography. A therapeutic digital subtraction angiography was performed for stent placement.
Subject(s)
Hypertension, Renal/diagnosis , Magnetic Resonance Angiography/methods , Renal Artery/pathology , Aged , Aged, 80 and over , Angiography, Digital Subtraction , Contrast Media , Female , Humans , Hypertension, Renal/therapy , Obesity/complications , Renal Artery Obstruction/diagnosis , Renal Artery Obstruction/therapy , StentsABSTRACT
To evaluate the reproducibility of measurements of left ventricular (LV) dimensions, function, and myocardial mass, segmented k-space gradient-recalled-echo (GRE) magnetic resonance (MR) imaging was performed on two occasions on 12 healthy volunteers. To compare the MR data, all volunteers underwent a two-dimensional echocardiography with determination of LV dimensions and function. The left ventricle was imaged during breath-hold by consecutive, contiguous short-axis views at end-diastole and end-systole. An average of eight short-axis views was needed to encompass the whole left ventricle. This fast MR sequence limited the total acquisition time to 12 min. LV volumes and masses were calculated after manual delineation of epicardial and endocardial surfaces by two observers in a blinded fashion. Interstudy variability varied between 4.1% and 10.3% for LV end-diastolic volume and end-systolic volume, respectively. Differences in interobserver variability were smaller and varied between 3.6% and 7.3% for LV ejection fraction and end-diastolic volume, respectively. Intraobserver variabilities ranged between 2.0% and 7.0% for LV ejection fraction and end-systolic volume, respectively. These variability percentages agree very well with other studies in literature using other MR sequences. No significant differences in LV dimensions or function were found between MR imaging and echocardiography. In conclusion, this MR sequence allows fast and reproducible LV quantification.
Subject(s)
Echocardiography/methods , Magnetic Resonance Imaging/methods , Ventricular Function, Left , Adult , Cardiac Output , Diastole , Humans , Male , Probability , Reference Values , Reproducibility of Results , Stroke Volume , SystoleABSTRACT
Left ventricular volume was determined in 12 healthy volunteers using a newly developed two-dimensional echocardiographic delineation method. The results were compared with those of magnetic resonance imaging, which served as the method of reference. Left ventricular end-diastolic volume was 123 +/- 12 ml, echocardiographically defined, and 121 +/- 12 ml calculated with magnetic resonance imaging. End-systolic volume was 41 +/- 7 ml on echocardiography and 37 +/- 6 ml on magnetic resonance imaging. Left ventricular ejection fraction was 67 +/- 4%, echocardiographically defined, and 70 +/- 5%, calculated with magnetic resonance imaging. There was no statistical difference for any of the measured parameters. Interstudy and inter-observer variability was minimal. In conclusion, in healthy volunteers left ventricular volume was accurately defined, using this newly developed two-dimensional echocardiographic delineation method. During endocardial delineation a dynamic display is continuously available on a second window, allowing precise visual edge-detection. Moreover, corrections can be made easily and quickly. These two advantages enhance the accuracy of the method, even in cases of poor echogenicity.
