Magnetic Resonance Imaging Analysis

NMR Homepage > NMR Laboratory Capabilities > NMR MRI Magnetic Resonance Imaging

Magnetic Resonance Imaging - MRI

Nuclear Magnetic Resonance Analysis Resources and Capabilities

MRI is one of the most recent and exciting developments in NMR and is a logical extension of the basic principles of magnetic resonance. The MR scanner provides a non-invasive method of imaging sensitive to subtle differences in water distribution, structural integrity, local flow and other measurements. Intertek laboratories offer expertise in MRI/NMR, including multi-slice, multi-echo and 3D resconctruction capabilities.

Materials characterisation applications include a range of polymeric materials such as plastics, rubbers and composites. Formulations applications include solid dosage form pharmaceuticals such as pills and tablets, and semi solids such as gels and pastes. Contact Intertek for more information.

Intertek NMR MRI expertise includes:

3D Reconstruction
Multi-echo
Multi-slice

NMR MRI principles:

According to the Larmor relationship, protons in a strong magnetic field precess faster than those in a weak field. If the magnetic field across an object, e.g. two H2O capillaries, is varied by means of a field gradient applied on top of the main magnetic field, The resonant frequency of the protons in the two sites will be different. Instead of a single NMR peak, two peaks are produced and the image is spatially localised.

Application of gradients in orthogonal directions can lead to the reconstruction of 2-D and 3D images using 2-D FT techniques. If the applied field gradient is linear, the frequency spectrum obtained after FT becomes a 1-D profile of proton (water) concentration versus distance in the chosen direction. This is known as 1-D mapping.