Comparison of Silent and Conventional MR Imaging for the Evaluation of Myelination in Children.

PURPOSE

Silent magnetic resonance imaging (MRI) scans produce reduced acoustic noise and are considered more gentle for sedated children. The aim of this study was to compare the validity of T- (TW) and T-weighted (TW) silent sequences for myelination assessment in children with conventional spin-echo sequences.

MATERIALS AND METHODS

A total of 30 children (21 boys, 9 girls; age range: 1-83 months, mean age: 35.5 months, median age: 28.5 months) were examined using both silent and spin-echo sequences. Acoustic noise levels were analyzed and compared. The degree of myelination was qualitatively assessed via consensus, and TW and TW signal intensities were quantitatively measured by percent contrast.

RESULTS

Acoustic noise levels were significantly lower during silent sequences than during conventional sequences (P < 0.0001 for both TW and TW). Inter-method comparison indicated overall good to excellent agreement (TW and TW images, κ = 0.76 and 0.80, respectively); however, agreement was poor for cerebellar myelination on TW images (κ = 0.14). The percent contrast of silent and conventional MRI sequences had a strong correlation (TW, correlation coefficient [CC] = 0.76; TW excluding the middle cerebellar peduncle, CC = 0.82; TW, CC = 0.91).

CONCLUSIONS

For brain MRI, silent sequences significantly reduced acoustic noise and provided diagnostic image quality for myelination evaluations; however, the two methods differed with respect to cerebellar delineation on TW sequences.