Reporting Radiographs Flashcards
X ray photons interact with the tissues and can be:
– Absorbed (not reaching image receptor)
- Scattered (reach image receptor but information not helpful)
–Pass through and reach image receptor giving useful information
Why are radiographic images made of varying shades of grey?
due to the different absorption of x-rays by the tissues
What structures appear white?
Dense structures absorb more x-rays
• E.g. enamel, cortical bone, metal
What structures appear dark grey?
Soft tissues
What structures appear black?
Air absorbs no photons so appears black
How should we view a radiograph film ?
– Darkened room
– A light box providing a homogeneous light source, with an optional focal spot of bright light
– Magnifier.
How should we view a digital radiograph
– Darkened room
– Minimal direct and reflected light
– Diagnostic monitor with tested standards of resolution and contrast display
– Monitor positioned at eye level
What is SMPTE
A test pattern for monitors to ensure adequate image display for diagnosis
in SMPTE what do high and low contracts line pair to
Test resolution
Which contrast squares are central?
5% and 95%
What is a radiographic report?
description of any disease detected and a recording in the notes that the image has been clinically evaluated
Which radiographic images should have a radiograph report?
All of them- legal requirement
According to the IR(ME)R19, Who’s role is it to report a radiograph?
Operator role
According to the IR(ME)R19, what must the legal person provide?
procedures to ensure that a clinical evaluation of the outcome of each exposure is carried out and recorded.
When will the expose be unjustified and must not take place
If it is known prior to the exposure taking place that no clinical evaluation will occur
What should the contents of a radiographic report be?
• The report should demonstrate that each radiograph has been evaluated
• Record pathological findings and/or key negative findings
• A description of pathological findings to allow someone to visualise the image, even if they cannot see it
• Should include sufficient information so that it can be subject to later audit
When interpreting the images, you will be looking at one of these:
– of patients who are symptom free but you are checking for occult disease, for example caries on bitewings
– of patients with specific symptoms which direct you to a certain technique and pathology
What may help you see an incidental finding?
Look at the image methodically
What is the procedure for reporting a radiograph?
• View under optimum conditions
• Identify it is the correct patient
• Ensure the film is dated
• Correctright/leftorientation
• Identify film faults which may render diagnosis impossible
• Examine full radiograph with a systematic approach.
• Describe radiographic features of pathology
• Form a differential diagnosis
• Compare with previous imaging
– Assess for stability, progression or resolution.
What is the systematic approach for viewing radiographs
• Identify any artefacts which might be mistaken for pathology
• Identify normal anatomical features and variants of normal
• Teeth, apical tissues and periodontal tissues – URQ → ULQ → LLQ → LRQ
• Assess other structures
– Body/ramus of mandible on OPT – Antral floor
– Nasal cavity
Describe radiolucency
– Black on image
– Caused by area of decreased density
– More x-rays passing through to interact with receptor, e.g. air, less bone
Describe radiopacity/ radiodensity
– Whiter on image
– Fewer x-rays reaching receptor as resorbed by denser tissue e.g. bone
What dental diseases causes relative radiolucency?
Caries: loss of mineral in enamel and dentine
Periodontal disease: loss of bone at the alveolar crest
Some pathologies/anomalies can result in an increase in tissue volume or density, making it appear more..
Radiopaque
E.g supernumerary tooth
What is a lesion?
A lesion is a region in an organ or tissue which has suffered damage through injury or disease, such as a wound, ulcer, abscess, or tumour.
What do lesions look like in radiographic images?
Lesions have different characteristics, producing different radiographic appearances.
What do we look at when reporting a lesion?
• Location
• Size
• Density
– Radiolucent/ radiopaque/mixed density
• Shape
• Margins
• Effects on surrounding structures
What can we say about the location of a lesion?
• Maxilla/mandible/soft tissues
• Relation to teeth
– Which teeth
– Which part of tooth • Apex
• Root
• Crown
• Position above or below the ID canal
What can we say about the size of a lesion?
• Direct measurement
– Remember to give units e.g. cm, mm
– Some radiographs have inherent magnification (e.g. 1.2-1.7 x magnification in panoramics) so measurements may not be precise
• In the jaws we can describe size relative to adjacent structures.
What can we say about the density of a lesion?
• Homogeneous (uniform, smooth) – Radiolucent (dark)
– Radiopaque (light)
• Heterogeneous
– Mixed density
– Mix of radiolucent and radiopaque areas
What can we say about the shape of a lesion?
• Circular
• Lobulated
• Sausageshaped
• Expansile
• Unilocular
• Multilocular
• Pseudolocular
What can we say about the margins of a lesion?
• Smooth
• Lobular
• Irregular/ regular, smooth
• Corticated
• Partially corticated
• Well-defined
• Ill-defined/diffuse
Effect of lesions on bone cortices
– May be eroded
– Lesion may be expansile, ‘pushing’ and thinning the bony cortices as the bone is expanded.
Effect of lesions on teeth?
– Displaced
– Resorbed
• Inferiordentalcanal • Maxillaryantrum
Limitations of radiographs
• Remember a radiograph is a 2D representation of 3D structure
• Always consider need for another view at a different angle (Parallax technique/SLOB rule)
• This is especially important to – Localise a radiodensity
– Assess a fracture
What do the cortical margins of benign and slower growing lesions tend to look like?
Well defined cortical margins
What do the cortical margins of malignant, more rapidly growing lesions tend to look like?
More irregular, poorly defined margins
- related to speed of bone destruction
What do margins on infected lesions look like?
Ill-defined margins and can appear more sinister
What is a differential diagnosis?
is a list of possible conditions fitting the clinical scenario
What is a clinical differential diagnosis based on
clinical signs and symptoms
What is a radiological differential diagnosis based on
key features observed in imaging
radiological differential diagnosis can support or inform the clinical differential diagnosis.
Interpreting radiographs requires application of knowledge of what 4 things
– Optimal viewing conditions for looking at imaging
– Normal anatomy
– Radiographic artefacts
– Features of pathological lesions
