National Research Development Corporation

Other

British Technology Group Limited

Peter Mansfield

Roger J Ordidge

Barry L Chapman

Ronald J Coxon

David N Guilfoyle

Paul Martin Glover

Robert Turner

Allen N Garroway

Roger M Bowley

Alistair Howseman

Barry Leonard Chapman

Richard William Bowtell

Peter Kevin Grannell

Terence Baines

A novel approach to the design of gradient coils for MRI is introduced which takes into account from the start the effects of induced E-fields and hence currents in a patient subjected to time dependent magnetic field gradients. The approach has led to conceptually novel designs of gradient coils which comprise distributions of electrodes or tessellae placed around the basic coil structure. When properly energised the electrode arrays are able, in the simplest case, to reduce the maximum E-field experienced by the patient by approximately a factor of three over that experienced with a standard fingerprint or distributed transverse gradient coil, the comparison being done for the same gradient strength, same coil diameter and same ROI.

MRI gradient coils with reduced neural stimulation

A method of producing an acoustically quiet coil design comprising first inner and outer surface conductor portions on a first block of material and second inner and outer surface conductor portions on a second block of material and including forming said portions of said each of said inner and outer surface conductor portions to be substantially completely rigid and connecting said inner surface conductor portion of said first block to said inner surface conductor portion of said second block and said outer surface conductor portion of said first block to said outer surface conductor portion of said second block by columns, struts or ties to form a substantially rigid structure.

Active acoustic control with flexible joints in gradient coil design for MRI

An acoustically controlled magnetic coil system is provided in which suitable non-magnetic transducers are embedded in a block of acoustic material in which the coil is also embedded, the transducers being energised to oppose the vibratory noise generated by the coil when energised.

Active control of acoustic output in gradient coils

Active acoustic control in quiet gradient coil design for MRI

Method and apparatus for eliminating mutual inductance effects in

Acoustic screen

A sample mount for NMR microscopy and NMR spectroscopy which enables a specimen to be accurately placed within an NMR apparatus and if required in a preferred embodiment for the specimen to be examined under an optical microscope to enable the images to be accurately compared.

Sample mount for NMR microscopy

Echo-volumar imaging using 180 degree RF pulses

A magnetic resonant image of an object is produced by subjecting the object to an initial slice selection to provide an active region and by subjecting the active region to a plurality of 180.degree. RF pulses and appropriate amplitude modulated x and y gradients.

Echo planar imaging using 180 degrees pulses

Coil circuits

A resonant array for NMR for use at high frequencies, the array comprising two identical end structures and a plurality of continuous rods joining the identical end structures to comprise a plurality of or electrical circuit sections, the continuous rods being of electrically conductive material; the continuous rods thereby supporting the end structures a predetermined distance apart.

Resonant cavities for NMR

Zonal magnification of a selected area of an image produced by Echo Planar Imaging is acheived by taking images of a defined area in the presence of a selective 180.degree. R.F. control pulse so that subsequent processing produces a magnified image of the selected area with enhanced resolution.

Echo planar imaging systems

A nuclear magnetic resonance (NMR) method of producing a series of three or four dimensional spin parameter maps of a defined region, which spin parameter maps are displayable as a set of contiguous planar spin parameter maps with arbitrary orientation.

NMR imaging

A surface electrical coil structure for use as a signal receiver and/or transmitter with the desired magnetic field characteristics and which comprises a plurality of small coils positioned over or around a specified volume each coil being singly or severally electrically connected such that the flow of electrical current within each coil produces the desired signal response or magnetic field.

Surface electrical coil structures

The screen is provided by surrounding the coil producing the magnetic field with a set of electrical conductors the currents within the conductors being controlled in such a manner that the field is neutrailized in a specific region of space, the current distribution within the conductors being determined by calculating the current within a hypothetical superconductive shield which would have the effect of neutrailizing the field, the current through the conductors thereby being a substitute for the superconductive shield.

Growing community of inventors

Nottingham, United Kingdom

Peter Mansfield