This document discusses the basics of radiographic interpretation. It explains that radiographs create images based on the differential absorption of x-rays as they pass through various tissues, with metal and bone appearing white and gas appearing black. The document outlines the typical radiographic appearance of different tissues like bone, soft tissue, fat, and gas. It emphasizes that interpretation involves correlating radiographic findings with clinical history and evaluating images for abnormalities defined by characteristics like number, size, and location. The goal is to integrate radiographic and clinical information to make an accurate diagnosis.

1. DIAGNOSTIC IMAGING
VM 352
RADIOGRAPHIC
INTERPRETATION
Dr. M. Makungu
Department of Veterinary
Surgery and Theriogenology
2022

2. X-rays and radiograph
• A radiograph is an image of the number and
distribution of X-rays that pass through the patient
and strike the film
• Areas struck by a large number of X-rays appear
black (radiolucent)
• Areas struck by few X-rays appear white
(radiopaque)
• Between these two extremes is a range of gray film
tones

4. • X-rays are not absorbed homogenous
by the body- differential absorption
• Factors affecting absorption
- Physical density
- Atomic number
- Thickness

5. Physical density:

6. Thickness:

7. Basic radiographic opacities
• The basic radiographic opacities are a spectrum
from radiopaque (white) to radiolucent (black)
• The order of most radiopaque to most radiolucent
is:
Metal, bone, soft tissue/fluid, fat and gas
• E.g. fat is more radiolucent than soft tissue and
bone, but more radiopaque than gas
Metal Bone Soft tissue/
Fluid
Fat Gas

8. Bone opacity:
• Bone is assessed radiographically as being more
or less radiopaque than normal
- Normal bone
- Sclerotic bone: more radiopaque than normal
- Porotic bone: less radiopaque than normal
Porotic
Sclerotic
Normal

9. Soft tissue opacity:
• Includes the radiographic opacities of normal
soft tissue such as muscle, solid and fluid
filled organs
• Variation in volume
and thickness create
a spectrum of varying
opacities on the
radiograph
VD

10. Fat opacity:
• Fat is more radiolucent than bone and soft
tissue, but more radiopaque than gas/air
• Produces radiographic contrast for
differentiation
and visualization
of the edges of
organs and
structures

11. Gas opacity:
• Gas or air is the most radiolucent within
the body

12. Metal opacity:

13. Interpretation
• Correlate the patient information and radiograph
being evaluated
• At least 2 projections/views perpendicular to
each other
• Evaluate the positioning and technical factors
• Systematically evaluation:
- From outside to inside
- Inside (body systems e.g. respiratory, digestive)

15. • Describe radiographic
abnormalities based on
“Roentgen signs”
- Number
- Size
- Opacity
- Position/Location
- Margin/Contour
- Shape

17. • Integrate radiographic findings and clinical
data
• Diagnosis