Visual Assessment of Age-Related White Matter Hyperintensities Using FLAIR Images at 3 T: Inter- and Intra-Rater Agreement.

BACKGROUND

Age-related white matter hyperintensities are frequent incidental findings on T2-weighted brain MRI, and they are evaluated in clinical practice using a visual rating scale.

OBJECTIVE

To evaluate inter- and intra-rater agreement in MRI visual evaluations of age-related white matter hyperintensities made by two radiologists with different levels of experience using a visual rating scale.

METHODS

Two radiologists of two different levels of experience separately rated age-related white matter hyperintensities in 40 consecutive 3-tesla brain MRI scans using the Fazekas and Schmidt visual rating scale. Ratings were made on axial FLAIR (fluid-attenuated inversion recovery) sequences. Two readings were made by each radiologist. Intra- and inter-rater agreement was statistically determined by using Cohen's weighted kappa analysis.

RESULTS

Forty patients (21 females, 19 males; mean age = 57 ± 18.43 years) were included between September and October 2011. Mean values ± SD for visual scores were as follows: periventricular hyperintensities, between 1.175 ± 0.9 and 1.375 ± 0.89; number of deep white matter hyperintensity lesions, between 1.325 ± 1.18 and 1.575 ± 1.15, and extent of deep white matter hyperintensity lesions, between 0.925 ± 0.78 and 1.1 ± 0.74. Intra- and inter-rater agreement was very good (x03BA; values, 0.85-0.91 and 0.80-0.97, respectively) for each of the three visual scale criteria, with significant correlations between ratings (r = 0.95; p < 0.0001) and readings (r = 0.91; p < 0.0001).

CONCLUSION

Visual assessment of age-related white matter hyperintensities by radiologists using a visual scale on FLAIR sequence is reproducible. Differences in experience level do not influence readings. Visual scale use is thus justified in common practice.