This PET scan came from a tomograph capable of imaging a 6.75 mm thickness of tissue per plane. Click on image above to view full-size image. Another type of artifact is caused by normalization errors. By their geometry, direct planes have higher sensitivity than do cross planes. Click on image above to view full-size image.
Bone causes higher attenuation than does soft tissue.
Attenuation correction compensates for this weakening of the signal. Click on image above to view full-size image. Another type of artifact is related to the placement of the patient in the scanner. To decide whether the head was tilted in the gantry, first locate the petrous ridges or bones. Normal bone has no FDG metabolism.