Method, compounds and preparations for the identification of sentinel lymph nodes

1. Method for the identification of a sentinel lymph node in a subject comprising

a) administering to said subject a composition comprising microbubbles comprising a shell and a gas or gas precursor, said microbubbles having a mean particle size of about 0.25-15 μm in diameter and a pressure stability of at least 50% at a pressure of 120 mm Hg, and wherein the shell comprises negatively charged phospholipids in an amount of from 50-100%,

b) allowing said microbubbles to accumulate in said sentinel lymph node,

c) detecting said microbubbles in said sentinel lymph node using ultrasound, and

d) characterizing said sentinel lymph node as being benign or malignant according to the pattern of contrast enhancement within the lymph node.

2. Method according to claim 1 wherein the composition is percutaneously administered.

3. Method according to claim 1 , wherein the microbubbles are stable for pressure variations associated with ultrasound imaging of a mechanical index of at least 0.2.

4. Method according to claim 1 , wherein the composition further comprises a macrophage stimulating compound.

5. Method according to claim 1 , wherein the composition is interstitially administered.

6. Method according to claim 1 , further comprising applying image processing methods to enhance the difference in pattern of contrast enhancement between benign and malignant lymph nodes.

7. Method according to claim 1 , wherein the benign sentinel lymph nodes appear uniformly echogenic while malignant sentinel lymph nodes demonstrate a heterogenic enhancement pattern with both areas of increased echogenity and areas that do not enhance.