The assessment of mild encephalopathy with a reversible splenial lesion (MERS) using high b-value DWI

INTRODUCTION: Mild encephalitis/encephalopathy with a reversible splenial lesion (MERS) was shown to have a transient reduction in diffusion. Such changes would be used as an early detection to reduce excessive treatments and promote recovery without sequelae. The current research evaluated the high b-value (b = 3000 s/mm(2)) diffusion-weighted imaging (DWI) assessment in MERS. METHODS: Sixteen pediatric patients showed MERS used DWI (b = 1000 and 3000 s/mm(2)). To record number of lesions, the signal intensities, signal-to-noise ratios (SNRs), contrast-to-noise ratios (CNRs), contrast ratios (CRs), the apparent diffusion coefficients (ADCs) were measured in the normal parenchyma and lesions. RESULTS: Lesions were more apparent with high b-value. The ADC values and CNR in the lesions and surrounding normal brain parenchyma were relatively low at a high compared to standard b-value DWI (SNR: 144.67 ± 33.03, 85.72 ± 31.50; CNR: 20.82 ± 17.64, 49.62 ± 33.06; for b = 1000 and 3000 s/mm(2)). The CR was significantly higher at a high compared to low b-value DWI (CR: 0.06 ± 0.07 versus 0.40 ± 0.14). CONCLUSION: High b-value DWI could detect more lesions and could obviously improve the detection of lesions in pediatric patients with MERS.