MRI take home point (10)

• Image SNR increases linearly with pixel size.
• When two similarly acquired images are added or subtracted, the resulting image has a noise level that is square root of 2 higher than that in either image.
• The larger the lesion area or contrast, and the lower the noise, the easier the lesion is to detect.
• The rose model describes the relationship between lesion area, contrast, and noise for lesion detection; the larger the lesion area or contrast, and the lower the noise, the easier the lesion is to detect.
• Artifacts can be caused by imperfection of hardware including B0, B1, gradients, shielding, RF coils.
• Cross-talking in multi-slice MRI. Partial-volume artifacts.