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C Nolte-Ernsting

Publications and source records attributed to C Nolte-Ernsting.

At least 19 recordsLinked to original sources
PubMed2006

Detection of small pulmonary nodules in high-field MR at 3 T: evaluation of different pulse sequences using porcine lung explants.

To evaluate two MR imaging sequences for the detection of artificial pulmonary nodules inside porcine lung explants. 67 agarose nodules ranging 3-20 mm were injected into ten porcine lungs within a dedicated chest phantom. The signal on T1-weighted images and radiopacity were adjusted by adding 0.125 mmol/l Gd-DTPA and 1.5 g/l of iodine. A T1-weighted three-dimensional gradient-echo (T1-3D-GRE; TR/TE:3.3/1.1 ms, slice:8 mm, flip-angle:10 degrees ) and a T2-weighted half-Fourier fast-spin echo sequence (T2-HF-FSE; TR/TE:2000/66 ms, slice:7 mm, flip-angle:90 degrees ) were applied in axial orientation using a 3-T system (Intera, Philips Medical Systems, Best, The Netherlands), followed by CT (16x0.5 mm) as reference. Nodule sizes and locations were assessed by three blinded observers. In nodules of >10 mm, sensitivity was 100% using 3D-GRE-MRI and 94% using the HF-FSE sequence. For nodules 6-10 mm, the sensitivity of MRI was lower than with CT (3D-GRE:92%; T2-HF-FSE:83%). In lesions smaller than 5 mm, the sensitivity declined to 80% (3D-GRE) and 53% (HF-FSE). Small lesion diameters were overestimated with both sequences, particularly with HF-FSE. This study confirms the feasibility of 3 T-MRI for lung nodule detection. In lesions greater than 5 mm, the sensitivity of the 3D-GRE sequence approximated CT (>90%), while sensitivity and PPV with the HF-FSE sequence were slightly inferior.

Animals↗
PubMed2006

[Multislice CT urography (MSCTU): evaluation of a modified scan protocol for optimized opacification of the collecting system].

PURPOSE: To retrospectively quantify opacification of the urinary tract using a MSCTU protocol based on furosemide and individual adaptation of urographic acquisition delay. MATERIALS AND METHODS: MSCTU examinations obtained from 4-row and 16-row CT scanners in 53 patients (35 men, 18 women, average age 59) were independently reviewed by two radiologists. MSCTUs were performed using a low-dose injection of furosemide. No fixed scan delay for urographic image acquisition was applied. The urographic timing was individually adapted by performing low-dose test images of the distal ureters to display their current opacification. Image analysis included grading of the opacification of the segmented collecting system. The average urographic delay was calculated. Stratified comparisons of mean scores were assessed using the Friedman and Wilcoxon tests. The inter-observer kappa value was calculated. RESULTS: The calculated median scan delay for patients with normal serum-creatinine levels (n = 51) was 418 sec (mean 447 sec; SD, 118 sec). The median number of acquired test images was 2 (range 1 - 6 images). The opacification analysis demonstrated that 98 % of the ICS, 90 % of the proximal, 86 % of the middle, and 83 % of the distal ureteral segments showed opacification greater than 90 %. 9.5 % of the distal ureteral segments could not be visualized. Statistics did not show significant opacification differences between proximal, middle, and distal ureteral segments (p > 0.05). The two observers were largely in agreement (kappa coefficient r = 0.81). CONCLUSION: The analyzed MSCTU technique based on furosemide and scan delay timing by means of test images reliably lead to a homogenous opacification of the entire upper urinary tract. It features the individual adaptation of MSCTU to the excretory rate of the kidneys.

Adolescent↗
PubMed2006

[Economic evaluation of angiographic interventions including a whole-radiology in- and outpatient care].

PURPOSE: To determine the economic efficiency of a whole-radiology in- and outpatient treatment with angiographic interventions performed as the main or sole therapy. MATERIALS AND METHODS: The calculations represent the data of a university radiology department, including the following angiographic interventions (neuroradiology not considered): Vascular intervention (PTA, stent implantation) of kidneys and extremities, recanalization of hemodialysis access, chemoembolization, diagnostic arterioportal liver CT, port implantation, varicocele embolization, PTCD, percutaneous implantation of biliary stent. First, the different angiographic interventions are categorized with reference to the German DRG system 2005. Considering the example of a university hospital, the individual cost of each intervention is calculated and correlated with reimbursements by G-DRG2005 and so-called "ambulant operation" (EBM200plus). With these data, profits and losses are calculated for both in- and outpatient care. RESULTS: Radiologic interventions of inpatients yield a profit in the majority of cases. With a base rate of 2900 euros, the profits in our university hospital range between - 872 euros and + 3411 euros (mean: + 1348 euros). On the other hand, those angiographic interventions suitable for "ambulant operation" generate average profits of + 372 euros, if only direct costs are considered. The data of outpatient radiological interventions average between 381 euros up to 1612 euros lower than compared with profits obtained from in patient care. CONCLUSION: Once an angiographic intervention represents the major or sole therapy, German radiologists are advised to operate out- and inpatient care by themselves. In Germany, the G-DRG-system and EBM enable radiology departments to generate considerable proceeds for their hospitals and, secondly, to yield a valuable add-on profit for their own department budget, which then is partly detached from the inflexible conventional reimbursement of radiological services.

Angiography↗
PubMed2006

[16-Row multidetector CT of the pelvis after iliosacrally inserted osteosynthetic screws: experimental study of dose adjustment on preserved human cadaver specimens].

PURPOSE: The study was performed to assess the necessity of dose adjustment (kV or mAs (eff.)) in 16-slice CT (MDCT) in postoperative controls of iliosacrally inserted osteosynthetic screws (OS) on preserved human cadaver specimens. The minimal tube settings for diagnostic imaging of the pelvic bone were analyzed and the effective doses and important organ doses were calculated. MATERIALS AND METHODS: 16 preserved human cadaver specimens with transiliac osteosynthetic screws were scanned on a 16-slice CT (collimation 16 x 0.75 mm, pitch 0.7) with 10 different tube settings (35, 50, 75, 100, 150 mAs (eff.) and 120 and 140 kV). 32 datasets (blinded for name and scan parameters) with and without OS were independently evaluated by four observers. The 10 series were sorted by subjective image quality (image noise, contours, artifacts), and the series with the lowest but still diagnostic quality was selected. The statistical analysis included multi-rater-kappa-test and Wilcoxon test for paired samples. RESULTS: The multi-reader agreements for sorting the series were fair (kappa = 0.38). The agreements in comparing the lowest diagnostic image qualities were slight to fair (kappa = 0.08-0.23). The paired sample test comparing the lowest diagnostic image quality with and without OS showed no statistical significance (p = 0.29). 87.5 % of the readouts (n = 64 [16 examinations, 4 readers]) with OS and 78.1 % of those without OS could be adequately diagnosed using the three series with the lowest effective doses (0.9-1.4 mSv for men, 1.4-2.0 mSv for women; 120 kV-35 mAs (eff.), 120-50, 140-35). CONCLUSION: MSCT scans of the pelvic bone can be performed with very low effective doses. It is not necessary to adjust tube settings when imaging bones with osteosynthetic screws. If the concept for the control of the pelvic osteosynthetic screw position includes more than 2 conventional films (for example anterioposterior view with additional inlet and outlet views), a low dose CT is preferable to conventional radiography.

Animals↗
PubMed2006

[Modern diagnostic assessment of the upper urinary tract using multislice CT urography].

The advent of Multislice Computed Tomography (MSCT) has made evaluation of the entire urinary tract with high-resolution sections during a single breath-hold a reality. Acquisition of multiple thin overlapping slices provides excellent two-dimensional (2D) and three-dimensional (3D) reformations of the urinary tract. The concept of "Multislice CT Urography (MSCTU)" has emerged from this technical improvement. As a result, a wide range of pathologies inside and outside the urinary tract can be identified. During the last several years, MSCTU has challenged intravenous urography (IVU) in the evaluation of urinary tract abnormalities. Compared with IVU, MSCT(U) is more sensitive and specific in the detection and characterization of a variety of urinary tract disorders, including renal masses and urolithiasis. The main advantage of IVU has been its ability to offer excellent delineation of pelvicalyceal and ureteral anatomy and to depict subtle uroepithelial abnormalities. MSCTU has already shown promising results for overcoming this challenge. Optimal opacification and distension appear to be an essential requirement for a thorough evaluation of the collecting system. Dedicated preparation strategies have been developed to meet these technical difficulties. The biggest disadvantage of MSCTU is the significant radiation exposure. For broad routine clinical application, there is still a need for dose reduction protocols despite the ongoing technical developments in MSCTU. In this article, we outline the different concepts of technical processing for MSCTU and summarize the current role of MSCTU in the evaluation of the upper urinary tract.

Carcinoma, Transitional Cell↗
PubMed2005

Evaluation of spatial and temporal resolution for ECG-gated 16-row multidetector CT using a dynamic cardiac phantom.

Measurements of spatial and temporal resolution for ECG-gated scanning of a stationary and moving heart phantom with a 16-row MDCT were performed. A resolution phantom with cylindrical holes from 0.4 to 3.0 mm diameter was mounted to a cardiac phantom, which simulates the motion of a beating heart. Data acquisition was performed with 16x0.75 mm at various heart rates (HR, 60-120 bpm), pitches (0.15-0.30) and scanner rotation times (RT, 0.42 and 0.50 s). Raw data were reconstructed using a multi-cycle real cone-beam reconstruction algorithm at multiple phases of the RR interval. Multi-planar reformations (MPR) were generated and analyzed. Temporal resolution and cardiac cycles used for image reconstruction were calculated. In 97.2% (243/250) of data obtained with the stationary phantom, the complete row of holes with 0.6 mm was visible. These results were independent of heart rate, pitch, scanner rotation time and phase point of reconstruction. For the dynamic phantom, spatial resolution was determined during phases of minimal motion (116/250). In 40.5% (47/116), the resolution was 0.6 mm and in 37.1% (43/116) 0.7 mm. Temporal resolution varied between 63 and 205 ms, using 1.5-4.37 cardiac cycles for image reconstruction.

Electrocardiography↗
PubMed2005

[Multislice CT urography Aspects for technical management and clinical application].

The introduction of multislice computed tomography with its well-known advantages has made it possible to visualize the entire urinary tract with thin collimation during a breath-holding phase. CT data acquisition during urographic contrast enhancement for contiguous imaging of the entire upper urinary tract is termed "multislice CT urography" (MSCTU). Multiplanar reconstructions, maximum intensity projections, and average intensity projections can be rendered from the volume datasets to view the urogenital tract. MSCTU will play an important role in the future of modern uroradiology. This article describes the technical aspects involved in the course of the MSCTU examination and identifies additional potential indications for clinical application.

Anatomy, Cross-Sectional↗
PubMed2005

[Labeling of mesenchymal stem cells with different superparamagnetic particles of iron oxide and detectability with MRI at 3T].

PURPOSE: In vitro evaluation of labeling efficiency of human mesenchymal stem cells (hMSCs) with different types of superparamagnetic iron oxide nanoparticles as well as detection and quantification by MRI at 3T. MATERIAL AND METHODS: hMSCs were incubated for 24 hours with 5 ultrasmall superparamagnetic particles of iron oxide (USPIO) contrast agents (1 : 30 - 1 : 30,000) of different size, coating and core compound: Endorem, Resovist, citric acid coated magnetite cores of 3 nm (CMF3), 7 nm (CMF7) and 12 nm (CoF, core: cobalt ferrite). Iron uptake, intracellular retention, detection and quantification were evaluated with MRI up to 5 weeks after incubation by cytological analysis (Prussian blue), atomic absorption spectrometry and MR relaxometry measurements. RESULTS: An effective labeling of hMSCs was achieved using Resovist, CMF3 and CMF7 with mean iron concentrations of 5.1/1.8, 1.9/1.4 and 1.5/1.0 pg/cell (dilutions 1:30 [933, 2100, 2800 microg Fe/ml]/1 : 300 [93, 210, 280 microg Fe/ml]) compared with 0.58/0.34 and 0.43/0.30 pg/cell (Endorem, CoF, dilution 1 : 30 [400, 4200 microg Fe/ml]/1 : 300 [40, 420 microg Fe/ml] unlabelled control cells: 0.01 pg/cell). Particle uptake correlated with the concentration of USPIO in the incubation medium. Detection of 5 x 10 (4) labelled cells/ml with MRI was possible up to 5 weeks after incubation (Resovist, CMF7 and CMF3). MR relaxometry measurements showed a strong correlation between cellular iron load and R2* (1/T2*), r > 0.78. No changes in cell viability or toxic effects were found. CONCLUSION: Efficiency of labeling hMSCs with USPIOs depends on coating, size and core compound of used particles. Carboxydextran-coated, clinically approved SPIO (Resovist, 50 nm) or ultrasmall citrate-coated particles (< 10 nm) result in an improved cellular uptake. In principle, the long intracellular retention of particles offers the possibility of cell tracking and migration monitoring in MRI.

Cells, Cultured↗
PubMed2004

MR elastography of the prostate: initial in-vivo application.

PURPOSE: To analyze the initial assessment of the technical feasibility of in-vivo MR elastography (MRE) of the prostate gland in healthy volunteers. MATERIALS AND METHODS: Dynamic sinusoidal MR elastography was performed in 7 healthy volunteers in prone position. The mechanical wave was induced via an external oscillator attached to the pubic bone. A 1.5 Tesla MR system (Philips Medical Systems, Netherland) was used with 4 combined surface coils for signal reception. MRE data acquisition was performed with a motion-sensitive spin-echo MR sequence that was phase-locked to the mechanical oscillation. Subsequently, these images were used to reconstruct the local distribution of elasticity inside the prostate gland. The applied reconstruction algorithm was tested by means of phantom measurements. RESULTS: Sufficient penetration of the mechanical wave into the prostate gland was achieved in all volunteers, allowing the acquisition of utilizable image data sets. The reconstructed distribution of elasticity (shear-modulus) inside the healthy prostate gland correlated with the zonal anatomy of the gland. The elasticity of the central portion (2.2 +/- 0.3 kPa) appeared to be lower than the peripheral prostatic portion (3.3 +/- 0.5 kPa). CONCLUSION: In-vivo MRE of the prostate gland is technically feasible. The proposed experimental set-up allows the efficient insertion of the mechanical wave into the prostate gland and provides a successful MR data acquisition.

Adult↗
PubMed2004

[Image quality of thin- and thick-slice MSCT reconstructions in low-contrast objects (liver lesions) with equal doses].

PURPOSE: To evaluate the image quality of thin-section MSCT examinations of low-contrast objects such as liver lesions, and to find out whether a thin slice technique requires an increase in radiation dose. MATERIALS AND METHODS: MSCT examinations of the liver were performed in the portal venous phase on a Volume Zoom Scanner (Siemens, Erlangen) with a collimation of 4 x 2.5 mm, 120 kV, 125 mAs and table speed of 12.5 mm. Forty small hypodense liver lesions with a mean size of 3 mm (1 to 8 mm) were reconstructed using a slice thickness of 3, 5, 7, and 10 mm. All lesions were evaluated for each slice thickness by 3 independent radiologists using a 5-point scale (excellent to poor) for the following 7 criteria: contrast, demarcation and contour of the lesion, image noise and quality, demarcation of liver veins and liver contour. The mean values of the reviewers' scores were calculated. The correlation of the three observers in the evaluation of the criteria was determined using the Kendall's Tau coefficient. RESULTS: The 3-mm thin sections were excellent in the evaluation of lesion detection, lesion contrast and lesion contour with a mean score of 1.4 compared to 4.1 for 10-mm sections. Concerning the criteria image quality and liver contour, thin sections achieved the best results in our series. Image noise was pronounced in thin sections but did not affect negatively the image analysis. Interrater agreement was 0.53 for the criterium image noise. CONCLUSION: Thin sections in MSCT examinations of low contrast objects such as liver lesions do not require an increase in radiation dose because the increase in image noise is compensated by improved lesion contrast.

Contrast Media↗
PubMed2004

Evaluation of balanced steady-state free precession (TrueFISP) and K-space segmented gradient echo sequences for 3D coronary MR angiography with navigator gating at 3 Tesla.

PURPOSE: To test the feasibility of k-space segmented gradient-echo pulse sequences for free-breathing coronary magnetic resonance angiography (cMRA) on a clinical 3T system. MATERIALS AND METHODS: T2-prepared, fat-suppressed turbo field echo (TFE, turboFLASH, SFPGR) as well as balanced TFE (b-TFE, trueFISP, FIESTA, segmented SSFP) sequences with navigator gating for prospective motion correction were applied on a 3T system equipped with a six-element phased-array cardiac coil. In 15 healthy volunteers, the right coronary artery (RCA) was examined with TFE and b-TFE sequences. Due to examination time limitations, the left coronary artery (LM/LAD) was examined exclusively with the TFE sequence in ten volunteers. Image quality was graded on a five point scale (0 = not visualized to 4 = excellent). The length, diameter and sharpness of the vessels and the contrast-to-noise ratios (CNR) were measured. RESULTS: 98 % of all major segments (proximal/middle/distal) of the RCA could be seen with the TFE sequence and 82 % with the b-TFE sequence. The image quality for the three segments was graded higher for the TFE sequence (2.7/2.7/1.5) than for the b-TFE sequence (1.9/1.6/0.9) with P: (< or = 0.001/< or = 0.004/< or = 0.056). The kappa of the interobserver variability was 0.75 for the TFE sequence and 0.8 for the b-TFE sequence. The measured vessel lengths were longer for the TFE sequence (95 +/- 22 mm) than for the b-TFE sequence (80 +/- 40 mm; P < or = 0.115). No significant changes (P < or = 0.074, P < or = 0.145) in diameter and vessel sharpness of the RCAs were observed between the TFE (2.4 +/- 0.3 mm, 60 % +/- 5) and b-TFE sequences (2.4 +/- 0.3 mm, 62 % +/- 6). The CNR was higher for the TFE sequence (10.1 +/- 3.4) than for the b-TFE sequence (6.6 +/- 2.1; P < or = 0.014). All ten main and proximal segments of the LM/LAD, which were examined exclusively with the TFE sequence, were visible with grade 2.5 and 2.1. The middle segment was visible in seven cases with grade 1.3. In three cases, the distal segment was visible with grade 0.5. The vessel length was 78 +/- 27 mm and the CNR 11.9 +/- 2.4. CONCLUSION: The conventional TFE technique has demonstrated good feasibility for cMRA at 3T. In its operational availability at 3T, the b-TFE sequence is inferior to the TFE sequence.

Adult↗
PubMed2004

[Multislice CT of the pelvis: dose reduction with regard to image quality].

PURPOSE: To optimize the examination protocols of multislice CT (MSCT) of the pelvis for dose reduction with regard to image quality. MATERIALS AND METHODS: MSCT of the pelvis was performed on 5 cadaver specimens with stepwise reduction of the tube current at 140 kV (250, 200, 150, 100, 75, 50, 35, 25 mAs) and 120 kV (50, 27 mAs). The remaining scan parameters like collimation (4 x 1 mm) and table speed of 4 mm per rotation remained unchanged. Axial sections and coronal reconstructions were used to evaluate cortex, trabecular structures, subjective image quality, image noise and detail detectability (pelvis and SI joint), with evaluation performed independently by four blinded experienced radiologists on a 5-point scale. Kappa coefficient, accuracy of the observers to sort the films with regard to dose reduction and mean scores of image evaluation were determined for statistical analysis. RESULTS: The deterioration of the image quality was most pronounced for all criteria between 75 mAs and 50 mAs at 140 kV. Good results with adequate image quality were obtained for detail detectability at 50 mAs and 140 kV (effective dose [E]: 3.3 mSv) and for the remaining four criteria at 75 mAs (E: 4.9 mSv). There was a moderate agreement between the four observers (kappa coefficient: 0.27). All observers were excellent in arranging the images according to the increasing dose reduction. CONCLUSIONS: Image quality of MSCT of the pelvis appears to be acceptable at 75 mAs and 140 kV with the dose reduced to 46% of the average value of the nation-wide survey of the German Roentgen Society in 1999 for this type of examination.

Acetabulum↗
PubMed2003

[MR-urography and CT-urography: principles, examination techniques, applications].

MR-urography (MRU) and CT-urography (CTU) provide refined imaging of the upper urinary tract not achievable with conventional intravenous urography (IVU). The traditional MR-urographic technique utilizes unenhanced, heavily T2 -weighted turbo spin-echo sequences for obtaining static fluid images of the urinary tract independent of the excretory renal function. T2 -weighted MR-urograms have proved to be excellent in visualizing the dilated urinary tract, even in non-excreting kidneys. In contrast, T1 -weighted MRU reflects the excretory renal function and displays the urine flow through the upper tract after renal excretion of an intravenously administered gadolinium chelate. The gadolinium-enhanced urine is visualized with fast T1 -weighted 3D-gradient-echo sequences. The combination of gadolinium and low-dose furosemide (5 - 10 mg) is the key for achieving a uniform distribution of gadolinium in the collecting system and for avoiding susceptibility artifacts (T2*-effects) in the urine. T1 -weighted excretory MRU provides impressive urograms of both non-dilated and obstructed collecting systems in patients with normal or moderately impaired renal function. Multislice-CT-urography (MS-CTU) is also an excretory urography like T1 -weighted MRU. Furthermore, MS-CTU can be combined with low-dose furosemide for accelerated passage of excreted contrast material obviating the need for abdominal compression. CT-urography is limited by its radiation burden and the nephrotoxicity of radiographic contrast media. Combining MRU or MS-CTU with conventional MRI or CT offers several applications, e.g., diagnosis of intrinsic and extrinsic tumors. Meanwhile, MRU has replaced IVU in pediatric uroradiology and is also recommended for the assessment of renal transplants. MS-CTU may provide valuable information in chronic urolithiasis, especially if associated with a distorted urinary tract anatomy. Both MRU and MS-CTU will play an important role in modern uroradiology.

Adolescent↗
PubMed2002

[Percutaneous sclerotherapy of a varicocele with atypical retrograde flow using a double-balloon occlusion technique].

OBJECTIVE: To perform a double-balloon occlusion for selective sclerosis of the internal spermatic vein in a varicocele with atypical retrograde flow. METHOD: In a 19-year-old man with a primary varicocele, phlebography demonstrated an 8-mm-wide internal spermatic vein with parallel collaterals and marked reflux of the contrast agent in the supine position. A single balloon occlusion could not prevent rapid wash-out of contrast material via collateral veins. Subsequently, two 8-mm balloon-catheters were sequentially inserted into the internal spermatic vein. After inflation of both balloons, the sclerosing agent was administered through the proximal catheter into the balloon-occluded venous segment. RESULT: Percutaneous sclerotherapy using the double-balloon technique achieved complete stasis inside the ectatic and retrograde perfused spermatic vein including its major parallel collaterals. CONCLUSION: In primary varicocele with strong spontaneous reflux and complicated flow pattern of the collateral veins, the double-balloon occlusion technique can achieve high local concentration of the sclerosing agent at optimal position and without wash-out effects.

Adult↗
PubMed2000

[Nuclear magnetic resonance tomography imaging and functional diagnosis of the eustachian auditory tube].

PURPOSE: To develop and evaluate a protocol for the anatomic depiction and functional testing of the auditory tube with the use of MR imaging. METHODS: Eleven volunteers were included into this study. For the morphological assessment, the imaging protocol included axial and coronal T2-weighted turbo-spin echo sequences (TR/TE = 3194/100 ms) and a T1-weighted gradient echo sequence (TR/TE = 42/4.6 ms). For the functional test a dynamic turbo-gradient echo sequence (TFE) with spectral fat suppression (TR/TE = 15/6.2 ms; 4 sec) was obtained using the single slice technique before and during the Valsalva manoeuvre. RESULTS: With multi-slice sequences, the osseous part of the auditory tube, the tubal cartilage (middle and lateral lamina), the ciliated epithelium, Ostmann's adipose body and the levator and tensor veli palatini muscles were delineated in all cases. During the Valsalva test, opening of the auditory tube was demonstrated in 20 of the 22 investigated sides using the dynamic TFE single slice sequence. CONCLUSIONS: The introduced MRI protocol allow visualization of the opening of the auditory tube and provides detailed anatomical information of the nasopharynx. Comprehensive morphological and functional evaluation of the auditory tube becomes possible within a single examination'.

Adult↗
PubMed2000

Transesophageal 3-dimensional echocardiography: in vivo determination of left ventricular mass in comparison with magnetic resonance imaging.

The objective of this study was to assess the accuracy and reproducibility of transesophageal 3-dimensional echocardiography (3DE) in comparison with magnetic resonance imaging (MRI) for the in vivo calculation of left ventricular mass (LVM). In addition, mass values obtained by M-mode echocardiography were compared with those calculated by MRI. Three-dimensional reconstruction of the left ventricle was performed from a transesophageal and transgastric transducer position with a multiplane transducer in 20 patients. Left ventricular mass was calculated from both transducer positions by using slices of various thicknesses, ranging from 5 to 20 mm. Reproducibility was determined by 5 repeated measurements of mass in each of 5 randomly selected left ventricles. M-mode echocardiography was performed according to the method described by Devereux. For MRI, multiple short-axis views with 10-mm slice thickness were acquired in inspiration hold. Correlation was high for mass determined by 3DE and MRI (for 10-mm slice thickness: r = 0.99; y = 0.99 x - 0.7 g; standard error of estimate = 8.5 g; P <.001). There was no statistical bias, and the limits of agreement ranged from +/-16.4 g to +/-27.2 g, depending on the slice thickness. Variability was lowest for a slice thickness of 10 mm (SD +/- 8.2 g). The reproducibility of mass determination was excellent (mean width of the 95% CI 12.8 g). Left ventricular mass values calculated from the transgastric and transesophageal transducer position were not different from each other (mean bias 0.6 +/- 9.1 g; P = ns). M-mode-based LVM calculations showed systematic overestimation and large measurement variability (bias 23.7 g; 95% CI +/- 92.8 g). Compared with MRI, transesophageal 3DE is an accurate and reproducible method for the determination of LVM and clearly superior to M-mode echocardiography.

Adult↗