Biomedical subjects

Marc van Cauteren

Publications and source records attributed to Marc van Cauteren.

2 recordsLinked to original sources

PubMed2004

Centrically reordered inversion recovery half-Fourier single-shot turbo spin-echo sequence: improvement of the image quality of oxygen-enhanced MRI.

PURPOSE: The purpose of the study presented here was to determine the improvement in image quality of oxygen-enhanced magnetic resonance (MR) subtraction imaging obtained with a centrically reordered inversion recovery half-Fourier single-shot turbo spin-echo (c-IR-HASTE) sequence compared with that obtained with a conventional sequentially reordered inversion recovery single-shot HASTE (s-IR-HASTE) sequence for pulmonary imaging. MATERIALS AND METHODS: Oxygen-enhanced MR imaging using a 1.5 T whole body scanner was performed on 12 healthy, non-smoking volunteers. Oxygen-enhanced MR images were obtained with the coronal two-dimensional (2D) c-IR-HASTE sequence and 2D s-IR-HASTE sequence combined with respiratory triggering. For a 256x256 matrix, 132 phase-encoding steps were acquired including four steps for phase correction. Inter-echo spacing for each sequence was 4.0 ms. The effective echo time (TE) for c-IR-HASTE was 4.0 ms, and 16 ms for s-IR-HASTE. The inversion time (TI) was 900 ms. To determine the improvement in oxygen-enhanced MR subtraction imaging by c-IR-HASTE, CNRs of subtraction image, overall image quality, and image degradation of the c-IR-HASTE and s-IR-HASTE techniques were statistically compared. RESULTS: CNR, overall image quality, and image degradation of c-IR-HASTE images showed significant improvement compared to those s-IR-HASTE images (P<0.05). CONCLUSION: Centrically reordered inversion recovery half-Fourier single-shot turbo spin-echo (c-IR-HASTE) sequence enhanced the signal from the lung and improved the image quality of oxygen-enhanced MR subtraction imaging.

Adult↗

PubMed2003

Time-resolved contrast-enhanced pulmonary MR angiography using sensitivity encoding (SENSE).

PURPOSE: To evaluate the relationship between gadolinium concentration and signal-to-noise ratio (SNR) on sensitivity encoding (SENSE) images, and determine the appropriate bolus injection protocol for visualizing pulmonary circulation. MATERIALS AND METHODS: Eighteen different gadolinium concentration phantoms (0, 0.01, 0.05, 0.1, 0.2, 0.4, 0.6, 0.8, 1.0, 1.2, 1.5, 2.0, 5.0, 10.0, 20.0, 30.0, 50.0, and 100.0 mmol/L) were analyzed to determine the relationship between gadolinium concentration and SNR on SENSE images in a phantom study. In an in vivo study, 3 mL (protocol A) or 6 mL (protocol B) of Gd-DTPA BMA at 3 mL/second, and 5 mL of Gd-DTPA BMA at 5 mL/second (protocol C) were administered to eight normal volunteers for contrast-enhanced (CE) pulmonary MR angiography (MRA) with SENSE. The peak SNRs of pulmonary parenchyma and the difference in SNR between pulmonary artery (PA) and pulmonary vein (PV) at peak SNR in the PA were statistically evaluated. RESULTS: For each flip angle at each gadolinium concentration, the SNRs and contrast-to-noise ratios (CNRs) of the SENSE images were significantly lower than those acquired with a nonparallel imaging technique (P < 0.05). The peak SNR of the pulmonary parenchyma, and differences in SNR between the PA and PV at the peak SNR of the PA obtained with a 5-mL/second bolus injection protocol were found to be significantly higher than those obtained with other protocols (P < 0.05). CONCLUSION: 3D-CE-MRA using SENSE demonstrated linearity between gadolinium concentration and SNR, and resulted in MRA with high spatial and temporal resolution with the aid of a sharp bolus injection protocol.

Adult↗