Hemispheric thickness as covariate

While attempting asymmetry analysis, I am planning to use hemisphere cortical mantle thickness as global covariate – but how to arrive at this measure? The aparc algorithm does not give this value. Is there any code/script that I could use?

Thanks in advance
LKP
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Lena Palaniyappan
Division of Psychiatry ( University of Nottingham)
South Block 'A' floor| Queens Medical Centre | Nottingham | NG7 2UH

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