Single breath-hold diffusion-weighted MRI of the liver with parallel imaging: initial experience

AimTo evaluate prospectively the improvement in the signal:noise ratio (SNR), with the use of parallel technique in single breath-hold diffusion-weighted imaging (DWI) of the liver and its affect on apparent diffusion coefficient (ADC) measurements.Materials and methodsThis study was approved by our institutional review board. Written informed consent was obtained from all participants. Fifteen patients underwent single breath-hold DWI of the liver with and without parallel imaging technique. SNR and ADC values were measured over a lesion-free right hepatic lobe by two radiologists in both series. When a focal hepatic lesion was present the contrast:noise ratio (CNR) and ADC were also measured. Paired Student's t-tests were used for statistical analysis.ResultsMean SNR values of the liver were 20.82 ± 7.54 and 15.83 ± 5.95 for DWI with and without parallel imaging, respectively. SNR values measured in DWI using parallel imaging were found to be significantly higher (p < 0.01). Mean ADC of the liver were 1.61 ± 0.45 × 10−3 mm2/s and 1.56 ± 0.28 × 10−3 mm2/s for DWI with and without parallel imaging, respectively. No significant difference was found between the two sequences for hepatic ADC measurement (p > 0.05). Overall lesion CNR was found to be higher in DWI with parallel imaging.ConclusionParallel imaging is useful in improving SNR of single breath-hold DWI of the liver without compromising ADC measurements.