Principles of radiographic interpretation

Islam Kassem Consultant oral & maxillofacial surgeon

ikassem@dr.com

Definition

Interpretation of radiographs can be regarded as

an unraveling process — uncovering all the information contained within the black, white and grey radiographic images.

ikassem@dr.com

Interpretation of radiographs can be regarded as an unraveling process — uncovering all the information contained within the black, white and grey radiographic images.

ikassem@dr.com

II-Essential requirements for interpretation

1- Optimum viewing conditions 2- Understanding the nature and limitations of the black,

white and grey radiographic image 3- Knowledge of what the radiographs used in dentistry

should look like, so a critical assessment of individual film quality can be made

4-Detailed knowledge of the range of radiographic appearances of normal anatomical structures

5- Detailed knowledge of the radiographic appearances of the pathological conditions affecting the head and neck

6- A systematic approach to viewing the entire radiograph and to viewing and describing specific lesions

7- Access to previous films for comparison.

ikassem@dr.com

1- Optimum viewing conditions

• An even, uniform, bright light viewing screen (preferably of variable intensity to allow viewing

of films of different densities) • A quiet, darkened viewing room • The area around the radiograph should be masked by a dark surround so that light passes only through the film • Use of a magnifying glass to allow fine detail to be

seen more clearly on intraoral films • The radiographs should be dry.

ikassem@dr.com

The nature and limitations of the radiographic image

ikassem@dr.com

2- Understanding the nature and limitations of the black, white and grey radiographic image

ikassem@dr.com

3- Knowledge of what the radiographs used in dentistry should look like, so a critical assessment of individual film quality can be

made

ikassem@dr.com

4-Detailed knowledge of the range of radiographic appearances of normal

anatomical structures

ikassem@dr.com

5- Detailed knowledge of the radiographic appearances of the

pathological conditions affecting the head and neck

ikassem@dr.com

6- A systematic approach to viewing the entire radiograph and to viewing

and describing specific lesions

ikassem@dr.com

7- Access to previous films for comparison.

ikassem@dr.com

Principles of Radiographic Interpretation

Imaging as an Examination Tool

Clinical examination

Signs

Symptoms

Ordering the right type of imaging examination

Ordering the right number of imaging examination

Necessary vs. unnecessary examinations

Benefit to the patient

Viewing condition

View box Monitor Prints Ambient light reduced Quiet room Intraoral films mounted on a opaque holder Equal intensity of light on the view box Monitors: calibration Magnification Software limitations

Systematic Approach

Intraoral images

Teeth, periodontium, bone, adjacent structures

Tooth #1 to #16, and then #17 to #32

Extraoral images;

Panoramic, other extraoral plain radiographs

Cross sectional images

CT, MRI

Localize the abnormality

How many lesions?

Where is the lesion?

Localized vs generalized

Single arch or both the arches

Inside the bone or outside

Relation to the crown

Relation to the root

Superior to the mandibular canal

Periphery

Well defined or ill defined?

Sharp margins

Corticated margins

Sclerotic margins

Radiolucent band

Blends into adjacent area

Irregular margins

Shape

Circular

Oval

Scalloped

Multilocular

Internal structures

Radiolucent

Mixed

Radiopaque

Trabeculation

Septa

Calcifications

Tooth or similar entities

Adjacent structures

Teeth

Lamina dura

Crestal bone

Periodontal spaces

Alveolar bone

Nerve canals

Maxillary sinuses

Cortical bones

Radiographic findings

Abnormal

Developmental Acquired

Cysts Tumors

(benign/malig) Inflammatory Bone dysplasia Vascular Metabolic Trauma

Normal

Vindicate your D/D

Vascular Infection Neoplasm Drugs Idiopathic/inflammatory Congenital Autoimmune Trauma Endocrine/metabolic

Irrelevant words!

Sun-ray appearance

Ground glass

Cotton wool

Onion skin

Driven snow

Etc, etc

When not to order imaging

You have not clinically / radiographically evaluated the patient

No benefit to the patient

Additional images may not provide extra information

No ‘routine’ radiograph

What goes on the report

Patient, doctor, clinic identification

Date, type and number of examination

Reasons for the examination

Clinical information

Relevant observation

Radiographic Impressions

Any further tests, examinations

ikassem@dr.com

Thank you