Table 2.

Comparison of mean diffusivity (MD) and fractional anisotropy (FA) in the genu of the corpus callosum in patients and control subjects

	CN	PD	PDD
GCC				CN > PD	CN > PDD	PD > PDD
FA	0.52 ± 0.03a	0.52 ± 0.03	0.49 ± 0.04	NS	P < 0.005c	P < 0.005c
				CN < PD	CN < PDD	PD < PDD
MDb	1.01 ± 0.07	1.04 ± 0.08	1.13 ± 0.10	NS	P < 0.00014c	P < 0.0013c

GCC genu of the corpus callosum, PD Parkinson’s disease, PDD Parkinson’s disease with dementia, CN control subjects

^aValues are means ± standard deviation

^bDiffusivity values are expressed as 10⁻³ mm²/s

^cStatistical significance (P < 0.05)