New MRI visual rating scales

Six visual rating scales, three alreary described: medial temporal, posterior, anterior temporal and three new/addapted: orbito-frontal, anterior cingulate and fronto-insula) were assessed in this study

Time to perform visual rating
Mean time to perform and record all six visual rating scales based on three raters assessing the subset study population ( n = 80) was 2.9 ± 1.3 min. Individual rater means and standard deviations were 2.7 ± 1.1, 2.4 ± 1.0 and 3.6 ± 1.6 min.

Inter-rater reliability of visual rating scores
Single measure and average measure ICC results for each scale are shown in Supplementary Table 1 . For the single measures ICC values, representing the reliability of each scale at the level of the individual rater, the MTA scale performed best overall, with very similar results achieved with two raters assessing all 257 scans, and four raters scoring 80 scans [ICC(2,1) ≥ 0.79]. The PA, OF and FI scales also demonstrated good reliability [ICC(2,1) ≥0.71] based on two raters assessing the total study population; reliability was slightly reduced when performed by four raters in the subset population [ICC(2,1) ≥ 0.58]. The reliability of the AC scale was lowest overall [ICC(2,1) range = 0.49–0.62]. As expected, the reliability based on mean rater scores was consistently greater for all scales [ICC(2,k) ≥ 0.73]. There were no material differences in reliability based on the larger or smaller population samples for any scale with the exception of the AT and AC scales, which were less reliable in the larger population sample.

Correlation of grey matter volume with visual rating scores
Voxel-based morphometry analysis revealed a negative partial correlation of higher visual rating score with lower grey matter density for all visual rating scales. 

Reference:
Lorna Harper, Giorgio G. Fumagalli, Frederik Barkhof, Philip Scheltens, John T. O’Brien, Femke Bouwman, Emma J. Burton, Jonathan D. Rohrer, Nick C. Fox, Gerard R. Ridgway, Jonathan M. Schott; MRI visual rating scales in the diagnosis of dementia: evaluation in 184 post-mortem confirmed cases. Brain 2016; 139 (4): 1211-1225. doi: 10.1093/brain/aww005https://academic.oup.com/brain/article-lookup/doi/10.1093/brain/aww005

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