Device and method for preventing magnetic-resonance imaging induced damage
An electromagnetic shield has a first patterned or apertured layer having non-conductive materials and conductive material and a second patterned or apertured layer having non-conductive materials and conductive material. The conductive material may be a metal, a carbon composite, or a polymer composite. The non-conductive materials in the first patterned or apertured layer may be randomly located or located in a predetermined segmented pattern such that the non-conductive materials in the first patterned or apertured layer are located in a predetermined segmented pattern with respect to locations of the non-conductive materials in the second patterned or apertured layer.
1 . A medical assist system, comprising:
a primary device housing;
said primary device housing having a control circuit therein;
a lead system to provide an electrical path between a tissue region and said primary device housing;
a shielding formed around said lead system to shield said lead system from electromagnetic interference; and
a filter, connected to said lead system, to attenuate any induced RF signal and passing a desired electrical physiological signal;
said filter including,
a shield enclosing said filter, and
a low pass filter connected to said lead system;
said shielding being patterned with non-conductive materials and conductive materials.
2 . The medical assist system as claimed in claim 1 , wherein said conductive material is a metal to shield said lead system from electromagnetic interference.
3 . The medical assist system as claimed in claim 1 , wherein said conductive material includes metal-coated carbon filaments to shield said lead system from electromagnetic interference.
4 . The medical assist system as claimed in claim 1 , wherein said conductive material is a polymer composite to shield said lead system from electromagnetic interference.
5 . The medical assist system as claimed in claim 1 , further comprising a non-permeable diffusion resistant biocompatible material covering said shielding.
6 . The medical assist system as claimed in claim 1 , wherein said shielding is formed around said primary housing to shield said primary housing from electromagnetic interference.
7 . The medical assist system as claimed in claim 6 , wherein said conductive material is a metal to shield said lead system and said primary housing from electromagnetic interference.
8 . The medical assist system as claimed in claim 6 , wherein said conductive material includes metal-coated carbon filaments to shield said lead system and said primary housing from electromagnetic interference.
9 . The medical assist system as claimed in claim 6 , wherein said conductive material is a polymer composite to shield said lead system and said primary housing from electromagnetic interference.
10 . The medical assist system as claimed in claim 1 , wherein said shielding is constructed of two patterned sheaths, each patterned sheath having non-conductive materials and conductive materials.
11 . The medical assist system as claimed in claim 10 , wherein said conductive materials in one of said two patterned sheaths are randomly located.
12 . The medical assist system as claimed in claim 10 , wherein said conductive materials in said two patterned sheaths are located in a predetermined segmented pattern.
13 . The medical assist system as claimed in claim 10 , wherein said conductive materials in said two patterned sheaths are located in a predetermined segmented pattern with respect to a direction substantially parallel with an axis of said lead system.
14 . The medical assist system as claimed in claim 10 , wherein said conductive materials in said two patterned sheaths are located in a predetermined segmented pattern with respect to a direction substantially perpendicular with an axis of said lead system.
15 . The medical assist system as claimed in claim 13 , wherein said conductive materials in said two patterned sheaths are located in a predetermined segmented pattern with respect to a direction substantially perpendicular with an axis of said lead system.
16 . The medical assist device as claimed in claim 1 , wherein said filter includes a common reference line coupled to said shield, said low pass filter being connected to said common reference line.
17 . The medical assist device as claimed in claim 1 , wherein said shield enclosing said filter is patterned with non-conductive materials and conductive materials.
18 . The medical assist device as claimed in claim 17 , wherein said conductive material of said shield is a metal.
19 . The medical assist device as claimed in claim 17 , wherein said conductive material of said shield includes metal-coated carbon filaments.
20 . The medical assist device as claimed in claim 17 , wherein said conductive material of said shield is a polymer composite.
21 . The medical assist device as claimed in claim 17 , wherein said shield is constructed of two patterned sheaths, each patterned sheath having non-conductive materials and conductive materials.
22 . The medical assist device as claimed in claim 21 , wherein said conductive materials in one of said two patterned sheaths are randomly located.
23 . The medical assist device as claimed in claim 21 , wherein said conductive materials in said two patterned sheaths are located in a predetermined segmented pattern.
24 . A medical assist system, comprising:
a primary device housing;
said primary device housing having a control circuit therein;
a lead system to provide an electrical path between a tissue region and said primary device housing;
a shielding formed around said lead system to shield said lead system from electromagnetic interference; and
a filter, connected to said lead system, to attenuate any induced RF signal and passing a desired electrical physiological signal;
said filter including,
a shield enclosing said filter, and
a low pass filter connected to said lead system;
said shielding being an apertured conductive material having a maximum aperture dimension of 0.01 millimeters to 10 millimeters.
25 . The medical assist system as claimed in claim 24 , wherein said conductive material is a metal to shield said lead system from electromagnetic interference.
26 . The medical assist system as claimed in claim 24 , wherein said conductive material includes metal-coated carbon filaments to shield said lead system from electromagnetic interference.
27 . The medical assist system as claimed in claim 24 , wherein said conductive material is a polymer composite to shield said lead system from electromagnetic interference.
28 . The medical assist system as claimed in claim 24 , further comprising a non-permeable diffusion resistant biocompatible material covering said shielding.
29 . The medical assist system as claimed in claim 24 , wherein said shielding is formed around said primary housing to shield said primary housing from electromagnetic interference.
30 . The medical assist system as claimed in claim 29 , wherein said conductive material is a metal to shield said lead system and said primary housing from electromagnetic interference.
31 . The medical assist system as claimed in claim 29 , wherein said conductive material includes metal-coated carbon filaments to shield said lead system and said primary housing from electromagnetic interference.
32 . The medical assist system as claimed in claim 29 , wherein said conductive material is a polymer composite to shield said lead system and said primary housing from electromagnetic interference.