Susceptibility

Where two materials with very different susceptibilities are closely adjacent, there may be severe distortion of the magnetic field, causing artefactual loss or exaggeration of the magnetic resonance signal. This is clearly seen in an image acquired with a metallic clip placed close to the scalp ( Plate.7). Ferromagnetic (highly paramagnetic) materials that may cause artefacts include metallic dental fillings and plates, hairgrips, ear or nose rings, and even some cosmetics. A less obvious form of susceptibility artefact arises if more (diamagnetic) tissue is situated at one end of the image field of view than the other. A field gradient is set up across the image resulting in signal loss. This is termed bulk susceptibility artefact and is often seen in images of both the head and neck ( Plate. . .. 7).

Funny Wiring Autism

Funny Wiring Autism

Autism is a developmental disorder that manifests itself in early childhood and affects the functioning of the brain, primarily in the areas of social interaction and communication. Children with autism look like other children but do not play or behave like other children. They must struggle daily to cope and connect with the world around them.

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