TABLE I.

Example scoring criteria to evaluate methods.

Score	Overall Image Quality	Signal-to-Noise Ratio	Sharpness
1	Nondiagnostic	All structures appear to be too noisy.	Some structures are not sharp on most images.
2	Limited	Most structures appear to be too noisy.	Most structures are sharp on some images.
3	Diagnostic	Few structures appear to be too noisy on most images.	Most structures are sharp on most images.
4	Good	Few structures appear to be too noisy on a few images.	All structures are sharp on most images.
5	Excellent	There is no noticeable noise on any of the images.	All structures are sharp on all images.