Solid hydrogel coupling for ultrasound imaging and therapy

A hydrogel coupling adapted to be disposed between an ultrasound transducer and at least one of a target and a physical boundary associated with a target, to acoustically couple the ultrasound transducer with at least one of a target and a physical boundary associated with a target, said hydrogel coupling comprising:

• a dimensionally stable hydrogel mass having:
• (a) a proximal surface configured to be disposed adjacent to an ultrasound transducer;
• and
• (b) a distal surface configured to acoustically couple with at least one of a target and a physical boundary associated with a target, wherein the dimensionally stable hydrogel mass has a melting point that is sufficiently high, and an acoustical absorbance that is sufficiently low to enable the dimensionally stable hydrogel mass to maintain its structural integrity when coupled with the ultrasound transducer, when:
• (i) said distal surface of said dimensionally stable hydrogel mass is disposed proximate a focal region of the ultrasound transducer;
• (ii) the ultrasound transducer is energized for a period ranging from about 1 second to about 100 seconds;
• and
• (iii) an intensity of an acoustical beam generated by the ultrasound transducer ranges from about 100 W/cm2 to about 10,000 W/cm2.

A kit for acoustically coupling an ultrasound transducer with a target, wherein such an ultrasound transducer is configured to apply high intensity focused ultrasound (HIFU) to a target, the kit comprising:

• (a) a dimensionally stable hydrogel mass having:
• (i) a proximal surface configured to be disposed adjacent to an ultrasound transducer used to apply HIFU to the target;
• and
• (ii) a distal surface configured to acoustically couple with at least one of the target and a boundary associated with the target, where the boundary is disposed between the ultrasound transducer and the target;
• and
• (b) a sealed package configured to maintain said dimensionally stable hydrogel mass in a hydrated condition until said dimensionally stable hydrogel mass is removed from said sealed package in preparation for use.

A method for using a dimensionally stable hydrogel mass to acoustically couple an ultrasound transducer with at least one of a target and a physical boundary associated with the target, wherein the ultrasound transducer is configured to apply high intensity focused ultrasound (HIFU) to a target, the method comprising the steps of:

• (a) selecting an input power level and a duration to be used to energize the ultrasound transducer;
• (b) providing a dimensionally stable hydrogel mass capable of maintaining its structural integrity when coupled to the ultrasound transducer used at the input power level and for the duration selected;
• (c) coupling a proximal surface of the dimensionally stable hydrogel mass to an outer surface of the ultrasound transducer;
• (d) coupling an outer extent of a distal surface of the dimensionally stable hydrogel mass to at least one of the target and a physical boundary separating the target from the distal surface of the dimensionally stable hydrogel mass;
• and
• (e) energizing the ultrasound transducer according at the input power level and for the duration selected.

A method for making a dimensionally stable hydrogel mass to acoustically couple an ultrasound transducer configured to apply a high intensity focused ultrasound (HIFU) to a target, wherein the dimensionally stable hydrogel mass includes a proximal surface configured to removably couple with the ultrasound transducer and a distal surface having an outer extent configured to couple with at least one of a target and a physical boundary separating the target from the ultrasound transducer, the method comprising the steps of:

• (a) mixing appropriate quantities of at least one monomer capable of forming a dimensionally stable hydrogel mass and a quantity of water sufficient to hydrate the at least one monomer that will be polymerized, to form a mixture;
• (b) introducing the mixture into a mold;
• (c) enabling the mixture in the mold to polymerize, forming the dimensionally stable hydrogel mass;
• and
• (d) removing the dimensionally stable hydrogel mass from the mold.