Outline and Guide for Learning

Blur, Visibility of Detail, and Resolution

Resources and References
The Physical Principles of Medical Imaging
Online Textbook
Visuals for Discussion

Mind Map Showing Factors Related to Medical Image Blurring

Introduction and Overview

Appearance of blur in everyday images (human vision, photography, etc)
Images of blur (point-spread and line-spread functions)
Blur shapes
Equivalent blur values

Effects of blur
Reduces visibility of detail and small objects
Produces image unsharpness
Reduces spatial resolution


Relationship of visibility of detail to blur
Significance of object size
Clinical significance of blurring

Spatial Resolution
Relationship to visibility of detail
Measurement of resolution

Modulation Transfer Function (MTF)

MTF curves
MTF curves comparing imaging systems with different amounts of blurring
Composite MTF curve for a system containing several sources of blurring

Relationship of MTF to visibility of detail
Calculation of MTF from blur values, how it is done

Blurring and visibility of detail in the different imaging modalities
Each imaging modality has specific sources of blurring
Comparison of blurring and visibility of detail for the modalities

NOTE: The sources of blurring with the different imaging modalities and how it is controlled is considered later in the units dedicated to the specific modalities.