Spatial Resolution in Radiography

These flashcards cover key terms related to spatial resolution in radiography, their definitions, and relevant concepts to assist in studying for the exam.

Spatial Resolution

The degree of geometric sharpness or accuracy of the structural lines recorded in an image.

Alias

A misrepresentation of signal frequencies caused by inadequate sampling.

Point Spread Function (PSF)

Measures blur and is used to quantify digital system spatial resolution.

Line Spread Function (LSF)

Expresses the boundaries of an image and is determined by imaging a narrow line.

Edge Spread Function (ESF)

Reflects the sharpness of borders in an image.

Nyquist Criterion

A principle stating that a signal must be sampled at least twice per cycle to accurately capture its details.

Modulation Transfer Function (MTF)

Measures the accuracy of an image compared to the original object on a scale of 0 to 1.

Unsharpness

The lack of definition or clarity in the image.

Temporal Resolution (TR)

The relationship between the duration of data acquisition and the motion of structures under study.

Low-Contrast Resolution

The ability to visualize subtle energy differences, particularly in soft tissues.

Penumbra

The imperfect, unsharp shadow surrounding a distinctly sharp area of a shadow (umbra).

Signal-to-Noise Ratio (SNR)

A measure of signal strength relative to total noise in an imaging system.

Contrast-to-Noise Ratio (CNR)

The ratio of the difference of signal intensities of two regions of interest to the imaging noise.