Devices and methods for acoustic shielding

Abstract

Acoustic shielding system and method for protecting and shielding non-targeted regions or tissues that are not intended to be treated by ultrasonic procedures from acoustic energy using a shield. In some embodiments, the shield comprises multiple layers made of one or more materials with one or more acoustic impedances. In some embodiments a multilayered shield includes materials with relatively different acoustic impedance levels. In some embodiments, the shield includes active components such as energy diversion devices, heating, cooling, monitoring, and/or sensing. In some embodiments, the shield is configured to protect an eye, mouth, nose or ear while allowing the ultrasound to treat the surrounding tissue. One embodiment of an eye shield is configured to fit under at least one eyelid and over a portion of the eye.

1 . An eye shield configured for selectively protecting an eye from acoustic energy applied to surrounding tissue, the eye shield comprising:
 a first layer comprising a first material with a first acoustic impedance;   a second layer in contact with and adjacent to the first layer, the second layer comprising a second material with a second acoustic impedance, the first acoustic impedance being at least ten times the second acoustic impedance; and   a third layer comprising a third material in contact with and adjacent to the second layer, the third material having a third acoustic impedance, the third acoustic impedance being at least ten times the second acoustic impedance.   
     
     
         2 . The shield of  claim 1 , wherein the first layer, the second layer and the third layer are configured to reduce acoustic transmission to the eye. 
     
     
         3 . The shield of  claim 1 , further an energy diversion device configured to remove or dissipate energy absorbed by the shield, the energy diversion device comprising at least one of the group consisting of a heat conduit, a coolant channel, a heat exchanger, a fluid circuit, and an electrical circuit. 
     
     
         4 . The shield of  claim 1 , further comprising a surface finish selected from the group consisting of a reflective surface, a smooth surface, a pitted surface, a sandblasted surface, a patterned surface, a surface with pockets, a surface with concave features, and a surface with convex features. 
     
     
         5 . A biocompatible shield configured for selectively protecting tissue from at least two energy sources, comprising:
 a first layer,   wherein the first layer comprises a first material with a first impedance; and   a second layer in contact with and adjacent to the first layer,   wherein the second layer comprises a second material with a second impedance,   wherein the first impedance is at least ten thousand times greater than the second impedance,   wherein the first layer and the second layer are configured to reduce transmission to a non-target region in a body of a subject, and   wherein at least one of the first layer and the second layer is configured to at least one of the at least two energy sources.   
     
     
         6 . The shield of  claim 5 , wherein the at least two energy sources comprise an ultrasound energy source and a photon-based energy source. 
     
     
         7 . The shield of  claim 5 , wherein at least one of the first layer and the second layer is configured to block a photon-based energy. 
     
     
         8 . The shield of  claim 5 , wherein one of the first layer and the second layer is opaque to a photon-based energy. 
     
     
         9 . The shield of  claim 5 , further an energy diversion device configured to remove or dissipate energy absorbed by the shield, the energy diversion device comprising at least one of the group consisting of a heat conduit, a coolant channel, a heat exchanger, a fluid circuit, and an electrical circuit. 
     
     
         10 . The shield of  claim 5 , further comprising a surface finish selected from the group consisting of a reflective surface, a smooth surface, a pitted surface, a sandblasted surface, a patterned surface, a surface with pockets, a surface with concave features, and a surface with convex features. 
     
     
         11 . A method of shielding a non-targeted region of a body from an emission of energy, the method comprising:
 positioning a shield between a non-targeted region of the body a source of emission of energy, the shield comprising at least two adjacent layers having a difference in acoustic impedance of a factor of at least 10,000;   emitting the energy into target tissue proximate to the non-targeted region of the body; and   blocking the energy transmission from the non-targeted region of the body   
     
     
         12 . The method of  claim 11 , wherein the at least two adjacent layers comprise:
 a first layer comprising a first acoustic impedance; and   a second layer in contact with the first layer, and comprising a second acoustic impedance being at least ten thousand times less than the first acoustic impedance.   
     
     
         13 . The method of  claim 11 , wherein the shield comprises:
 a first layer comprising a first acoustic impedance;   a second layer in contact with the first layer, and comprising a second acoustic impedance being at least ten thousand times less than the first acoustic impedance; and   a third layer comprising a third material in contact with the second layer and comprising third acoustic impedance being at least ten thousand times greater than the second acoustic impedance.   
     
     
         14 . The method of  claim 11 , further comprising cosmetically enhancing a portion of the target tissue. 
     
     
         15 . The method of  claim 11 , wherein the energy comprises ultrasonic energy and a second energy. 
     
     
         16 . The method of  claim 15 , wherein said at least one other energy comprises a photon-based energy. 
     
     
         17 . The method of  claim 15 , wherein a source of the second energy is a laser. 
     
     
         18 . The method of  claim 11 , further comprising applying energy from an ultrasonic transducer to target tissue proximate the upper eyelid and the lower eyelid. 
     
     
         19 . The method of  claim 11 , further comprising applying energy from an ultrasonic transducer for blepharoplasty. 
     
     
         20 . The shield of  claim 11 , further comprising dissipating energy from the shield wan an energy diversion device comprising at least one of the group consisting of a heat conduit, a coolant channel, a heat exchanger, a fluid circuit, and an electrical circuit.