ATXN3 and Machado-Joseph disease: Moreover, correlation analysis of the SCA3/MJD patients group revealed that the total ICARS score and disease duration were inversely correlated to the gray matter volume of cerebellar culmen, pons, and midbrain (p < 0.005), and the number of CAG repeats in expanded alleles was inversely correlated to the gray matter volume of cerebellar culmen (p < 0.01) (Table 3).