Table 3.

Breast tissue bulk optical properties ($\text{mean}\pm \mathrm{std}$) measured at four optical wavelengths of entire population and different races (total $n=285$, black $n=45$, Asian and Hispanic $n=46$, white $n=137$).

Background properties	Race	Chest wall depth (cm)	Wavelength
			740 nm	780 nm	808 nm	830 nm
${\mu }_{\mathrm{a}}$ (${\mathrm{cm}}^{-1}$)	All patients	$2.57\pm 0.66$	$0.033\pm 0.020$	$0.032\pm 0.022$	$0.034\pm 0.023$	$0.039\pm 0.023$
	Black	$2.58\pm 0.68$	$0.034\pm 0.022$	$0.033\pm 0.022$	$0.034\pm 0.023$	$0.039\pm 0.025$
	Asian and Hispanic	$2.49\pm 0.70$	$0.035\pm 0.020$	$0.036\pm 0.025$	$0.039\pm 0.027$	$0.042\pm 0.027$
	White	$2.53\pm 0.62$	$0.033\pm 0.020$	$0.032\pm 0.022$	$0.034\pm 0.022$	$0.039\pm 0.022$
${\mu }_{\mathrm{s}}^{\prime }$ (${\mathrm{cm}}^{-1}$)	All patients	$2.57\pm 0.66$	$4.5\pm 1.3$	$4.1\pm 1.2$	$3.7\pm 1.1$	$4.6\pm 1.1$
	Black	$2.58\pm 0.68$	$4.7\pm 1.6$	$4.4\pm 1.4$	$4.0\pm 1.3$	$4.2\pm 1.3$
	Asian and Hispanic	$2.49\pm 0.70$	$4.6\pm 1.3$	$4.1\pm 1.2$	$3.8\pm 1.1$	$4.1\pm 1.1$
	White	$2.53\pm 0.62$	$4.5\pm 1.2$	$4.0\pm 1.2$	$3.7\pm 1.1$	$4.1\pm 1.1$