Submicron contrast agents for the detection and localization of at risk lymph nodes

Ultrasound contrast agents can be readily administered to facilitate detection and localization of lymph nodes at risk for regional metastasis. The agent under observation is a sub-micron, gas-filled, double-walled microsphere that ruptures when exposed to ultrasound energy at megaHertz frequencies. Optically, we observe expansion of these microbubbles over an order of magnitude in radius. These results are supported with simulations from a modified Rayleigh-Plesset model.