Table 5.

Literature values for mechanical, ultrasonic and NMR properties of normal and abnormal breast tissue

		Ultrasound		NMR
Tissue type	Storage modulus	Propagation speed (m/s)	Atten. coeff. + freq. at 7 MHz (dB/cm/MHz)	T1 (ms)	T2 (ms)
Fibroadenoma	-	1584 ± 27b	-	1160 ± 336d	60 ± 11d,h
Cancer	93 ± 33a	1550 ± 35b	1.0 ± 0.2c	900 ± 225d	94 ± 48d
Glandular	33 ± 11a	1553 ± 35b	2.0 ± 0.7c	305e	49 ± 16d
Fat	19 ± 7a	1479 ± 32b	0.6 ± 0.1c	209 ± 17f 266 ± 45g	135 ± 16f 57 ± 3g

Values shown are means ± standard deviations, except for the case of T₁ for the glandular parenchyma where no standard deviation was given. Unless otherwise stated, values result from measurements in vitro at 37°C or in vivo. Typical values of the storage modulus and attenuation coefficient for fibroadenomas were not found in the literature.

^a= Krouskop et al. (1998) at 1 Hz and at room temperature;

^b= Scherzinger et al. (1989) in vivo;

^c= D’Astous and Foster (1986);

^d= Bottomley et al. (1987), Table 16, p 25. Values at 60 MHz, but temperature is not known;

^e= Koenig and Brown (1984), 50 MHz;

^f= Just and Thelen (1988), 12 MHz;

^g= Nyman et al. (1986), 15 MHz;

^h= Small number of samples (5).