Table 2:

MR Measurement of the AC and SI thicknesses*

	FTLD (n = 7)	AD (n = 20)	Control (n = 16)	P
AC area (mm²), AC thickness^† (mm)	5.45 ± 1.80, 2.23 ± 0.42	8.97 ± 1.84, 2.97 ± 0.50	12.47 ± 1.42, 3.67 ± 0.48	<.001^†, <.001
Average SI thickness (mm)	2.31 ± 0.17	2.17 ± 0.50	2.45 ± 0.33	.147
Right SI thickness (mm)	2.35 ± 0.19	2.11 ± 0.53	2.50 ± 0.36	.041^‡
Left SI thickness (mm)	2.28 ± 0.19	2.25 ± 0.56	2.45 ± 0.37	.419

Note:—AC indicates anterior commissure; SI, substantia innominata; FTLD, frontotemporal lobe degeneration; AD, Alzheimer disease.
* Values are mean ± SD.
† P < .01 between FTLD versus AD, FTLD versus control, and AD versus control.
‡ P < .05 between AD versus control.