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 magnetic-resonance imaging process, comprising:
(a) imaging a tissue region according to an image acquisition sequence;
(b) adjusting the image acquisition sequence, in response to a predetermined parameter, to allow for cooling of the imaged tissue region; and
(c) shielding components of a medical assist device with a shield patterned with non-conductive materials and conductive material.
2 . The magnetic-resonance imaging process as claimed in claim 1 , wherein the predetermined parameter is a relative temperature change of the tissue region being imaged.
3 . The magnetic-resonance imaging process as claimed in claim 1 , wherein the predetermined parameter is a specific absorption ratio at the tissue region being imaged.
4 . The magnetic-resonance imaging process as claimed in claim 1 , further comprising:
(d) measuring a temperature change of the tissue region being imaged; and
(e) determining if the measured temperature change is above a predetermined threshold;
the image acquisition sequence being automatically adjusted in response to the measured temperature change being determined to be above the predetermined threshold.
5 . The magnetic-resonance imaging process as claimed in claim 1 , further comprising:
(d) measuring a temperature change of the tissue region being imaged; and
(e) displaying the measured temperature change;
the image acquisition sequence being manually adjusted in response to the displayed measured temperature change being above a predetermined threshold.
6 . The magnetic-resonance imaging process as claimed in claim 1 , further comprising:
(d) measuring a temperature change of the tissue region being imaged; and
(e) determining if the measured temperature change is above a predetermined threshold;
the image acquisition sequence being automatically halted in response to the measured temperature change being determined to be above the predetermined threshold until the measured temperature change falls below the predetermined threshold.
7 . The magnetic-resonance imaging process as claimed in claim 1 , further comprising:
(d) measuring a temperature change of the tissue region being imaged; and
(e) displaying the measured temperature change;
the image acquisition sequence being manually halted in response to the measured temperature change being determined to be above the predetermined threshold until the measured temperature change falls below the predetermined threshold.
8 . The magnetic-resonance imaging process as claimed in claim 1 , further comprising:
(d) measuring a specific absorption ratio of the tissue region being imaged; and
(e) determining if the measured specific absorption ratio is above a predetermined threshold;
the image acquisition sequence being automatically adjusted in response to the measured specific absorption ratio being determined to be above the predetermined threshold.
9 . The magnetic-resonance imaging process as claimed in claim 1 , further comprising:
(d) measuring a specific absorption ratio of the tissue region being imaged; and
(e) displaying the measured specific absorption ratio;
the image acquisition sequence being manually adjusted in response to the displayed measured specific absorption ratio being above a predetermined threshold.
10 . The magnetic-resonance imaging process as claimed in claim 1 , wherein the shield includes a first patterned layer having non-conductive materials and conductive materials and a second patterned layer having non-conductive materials and conductive materials.
11 . The magnetic-resonance imaging process as claimed in claim 10 , wherein the conductive material is a metal.
12 . The magnetic-resonance imaging process as claimed in claim 10 , wherein the conductive material includes metal-coated carbon filaments.
13 . The magnetic-resonance imaging process as claimed in claim 10 , wherein the conductive material is a polymer composite.
14 . The magnetic-resonance imaging process as claimed in claim 10 , wherein the conductive materials in the first patterned layer are randomly located.
15 . The magnetic-resonance imaging process as claimed in claim 10 , wherein the conductive materials in the first and second patterned layers are located in a predetermined segmented pattern.
16 . The magnetic-resonance imaging process as claimed in claim 10 , wherein the conductive materials in the first patterned layer are located in a predetermined segmented pattern with respect to locations of the conductive materials in the second patterned layer.
17 . The magnetic-resonance imaging process as claimed in claim 10 , wherein the shield further includes a non-conductive layer between the first and second patterned layers.
18 . The magnetic-resonance imaging process as claimed in claim 17 , wherein the conductive materials in the first patterned layer overlap the conductive materials in the second patterned layer with respect to a direction substantially perpendicular to a planar surface of the second patterned layer.
19 . The magnetic-resonance imaging process as claimed in claim 10 , wherein the shield further includes a first non-conductive layer between the first and second patterned layers, a second non-conductive layer positioned such that the first patterned layer is between the first and second non-conductive layers, and a third non-conductive layer positioned such that the second patterned layer is between the first and third non-conductive layers.
20 . The magnetic-resonance imaging process as claimed in claim 10 , wherein the shield further includes a third patterned layer having non-conductive materials and conductive materials.
21 . The magnetic-resonance imaging process as claimed in claim 20 , wherein the conductive materials in the third patterned layer are located in a predetermined segmented pattern.
22 . The magnetic-resonance imaging process as claimed in claim 20 , wherein the conductive materials in the third patterned layer are located in a predetermined segmented pattern with respect to locations of said conductive materials in said first and second patterned layers.
23 . The magnetic-resonance imaging process as claimed in claim 20 , wherein a portion of the conductive materials in the third patterned layer overlap the conductive materials in the first patterned layer with respect to a direction substantially perpendicular to a planar surface of the first patterned layer.
24 . The magnetic-resonance imaging process as claimed in claim 10 , wherein the conductive material is carbon nanotubes.
25 . A magnetic-resonance imaging process, comprising:
(a) imaging a tissue region according to an image acquisition sequence;
(b) adjusting the image acquisition sequence, in response to a predetermined parameter, to allow for cooling of the imaged tissue region; and
(c) shielding components of a medical assist device with a shield being an apertured conductive material and having a maximum aperture dimension of 0.01 millimeters to 10 millimeters.
26 . The magnetic-resonance imaging process as claimed in claim 25 , wherein the predetermined parameter is a relative temperature change of the tissue region being imaged.
27 . The magnetic-resonance imaging process as claimed in claim 25 , wherein the predetermined parameter is a specific absorption ratio at the tissue region being imaged.
28 . The magnetic-resonance imaging process as claimed in claim 25 , further comprising:
(d) measuring a temperature change of the tissue region being imaged; and
(e) determining if the measured temperature change is above a predetermined threshold;
the image acquisition sequence being automatically adjusted in response to the measured temperature change being determined to be above the predetermined threshold.
29 . The magnetic-resonance imaging process as claimed in claim 25 , further comprising:
(d) measuring a temperature change of the tissue region being imaged; and
(e) displaying the measured temperature change,
the image acquisition sequence being manually adjusted in response to the displayed measured temperature change being above a predetermined threshold.
30 . The magnetic-resonance imaging process as claimed in claim 25 , further comprising:
(d) measuring a temperature change of the tissue region being imaged; and
(e) determining if the measured temperature change is above a predetermined threshold;
the image acquisition sequence being automatically halted in response to the measured temperature change being determined to be above the predetermined threshold until the measured temperature change falls below the predetermined threshold.
31 . The magnetic-resonance imaging process as claimed in claim 25 , further comprising:
(d) measuring a temperature change of the tissue region being imaged; and
(e) displaying the measured temperature change;
the image acquisition sequence being manually halted in response to the measured temperature change being determined to be above the predetermined threshold until the measured temperature change falls below the predetermined threshold.
32 . The magnetic-resonance imaging process as claimed in claim 25 , further comprising:
(d) measuring a specific absorption ratio of the tissue region being imaged; and
(e) determining if the measured specific absorption ratio is above a predetermined threshold;
the image acquisition sequence being automatically adjusted in response to the measured specific absorption ratio being determined to be above the predetermined threshold.
33 . The magnetic-resonance imaging process as claimed in claim 25 , further comprising:
(d) measuring a specific absorption ratio of the tissue region being imaged; and
(e) displaying the measured specific absorption ratio;
the image acquisition sequence being manually adjusted in response to the displayed measured specific absorption ratio being above a predetermined threshold.