AUDIO APPARATUS AND METHOD FOR USE IN PROXIMITY TO A MAGNETIC RESONANCE IMAGING SYSTEM

• US 20080118077A1
• Filed: 11/22/2006
• Published: 05/22/2008
• Est. Priority Date: 11/22/2006
• Status: Active Grant

• Current Assignee: Nordicneurolab As
• Original Assignee: Nordicneurolab As
• Inventors: RASMUSSEN, SVEIN REIDAR
• Granted Patent: US 8,085,942 B2
• Time in Patent Office: Days
• US Class Current: 381/71.3
• CPC Class Codes: A61B 5/055 involving electronic [EMR] or nuclear [NMR] magnetic resonance, e.g. magnetic resonance imaging
• CPC Class Codes: A61F 11/145 electric, e.g. for active noise reduction
• CPC Class Codes: G01R 33/283 Intercom or optical viewing arrangements, structurally associated with NMR apparatus
• CPC Class Codes: G10K 11/178 by electro-acoustically regenerating the original acoustic waves in anti-phase
• CPC Class Codes: G10K 11/17857 Geometric disposition, e.g. placement of microphones
• CPC Class Codes: G10K 11/17881 the reference signal being an acoustic signal, e.g. recorded with a microphone
• CPC Class Codes: G10K 11/17885 additionally using a desired external signal, e.g. pass-through audio such as music or speech
• CPC Class Codes: G10K 2210/1161 NMR or MRI

Abstract

An apparatus and method for presenting high-quality auditory stimuli, receiving patient communication and providing noise cancellation within the environment of magnetic resonance imaging (“MRI”) equipment. A microphone is positioned in a noise attenuated channel for recording of the patient'"'"'s voice. A microphone is disposed outside of a noise attenuated channel to directly record the sounds of MRI equipment during its operation. The signals generated by the microphones are employed to reduce the output of noise generated by MRI equipment.

Claims

1. A sound system for use within the fields associated with magnetic resonance equipment, comprising:

a rigid housing and molded pliable material shaped such that said material forms a channel when placed in contact with the human ear;

a microphone positioned within the channel;

a speaker positioned within the channel; and

an audio control circuit wherein a signal from the microphone is processed by subtracting a signal used to power the speaker such that the sound from the speaker is partially removed.

2. The device of claim 1 further comprising:

a second microphone positioned outside of the channel.

3. The device of claim 2 further comprising:

a second audio control circuit electrically connected to said second microphone and said speaker operable to subtract a signal received from said second microphone from an input signal for said speaker to result in a modified input signal to said speaker that reduces the sound outside of said channel presented to the human ear.

4. The device of claim 3 further comprising:

a third audio control circuit electrically connected to said microphone positioned within the channel, the input signal for said speaker, and the second microphone to compare the signal received from said second microphone with the signal from said microphone positioned within the channel to determine whether the noise presented to the human ear was substantially reduced.

5. The device of claim 4, wherein said molded pliable material is formed to provide a first region associated with said speaker and a second region associated with said microphone within the channel.

6. A noise cancellation system for use within the fields associated with magnetic resonance equipment, comprising:

a control unit for processing acoustic signals between a patient and an operator;

an attenuator to provide a degree of acoustic insulation that is formed to create a channel with the ear of a patient;

a first microphone connected as input to said control unit positioned outside of said attenuator;

a speaker connected as output to said control unit positioned inside of said attenuator; and

,

a second microphone that is connected as input to said control unit and positioned inside of said attenuator for sensing sound made by the patient.

7. The system of claim 6, wherein the control unit creates a modified input speaker signal by combining a signal from said second microphone with the electrical signal received to drive the speaker such that the perceptible noise of the environment is reduced.

8. The system of claim 6, wherein the control unit subtracts the modified input speaker signal from a signal from the microphone positioned within said attenuator for output to the operator.

9. The system of claim 6, wherein said attenuator is formed to provide a first region associated with said speaker and a second region associated with said second microphone inside of said attenuator.

10. A method of performing error correction of auditory signals presented to a patient located within the fields associated with MRI equipment, comprising:

receiving an output signal intended for presentation to the patient through a speaker;

creating a first input signal by sensing sound made by the MRI equipment;

combining the input signal to the output signal such that the output signal substantially cancels the sound made by the MRI equipment;

creating a second input signal by sensing the sound made by the speaker;

comparing the second input signal to the first input signal to adjust the combining to further cancel the sound made by the MRI equipment.