Table 3.

Changes in dielectric properties and location errors at 2.5 GHz in the differential imaging of a 1.0-cm-diameter malignant spherical inclusion in realistic heterogeneous phantoms using microbubble and carbon nanotube contrast agents.

Phantom		Exact Change (%)		Est. Change (%)		||r̂ − r*|| (mm)
Class	Agent	εrel	σeff	εrel	σeff	εrel	σeff
1	μ-bubble	−30	−30	−1.8	−1.2	4.5	2.8
	nanotube	+22	+60	+0.9	+0.8	6.0	3.5
2	μ-bubble	−30	−30	−6.6	−5.6	8.2	7.2
	nanotube	+22	+60	+4.1	+4.8	12	11
3	μ-bubble	−30	−30	−9.1	−8.5	4.5	4.5
	nanotube	+22	+60	+4.6	+6.8	8.2	4.5
4	μ-bubble	−30	−30	−6.6	−4.5	8.5	7.5
	nanotube	+22	+60	+4.6	+3.9	8.9	6.3