Principles of Radiographic Interpretation

Juan F. Yepes DDS, MD, MPHAssistant Professor

Division of Oral Diagnosis, Oral Medicine and Oral RadiologyUniversity of Kentucky, College of Dentistry

Spring 2009

What is that radiologist saying? Well defined andCorticated…..

The objective of this lecture is to provide step-by-step- analytic processthat can be applied to the interpretation of diagnostic images.

Proficiency comes with PRACTICE!!!

- Radiographic interpretation of caries

- Radiographic interpretation of periodontal disease

- Radiographic interpretation of benign conditions

- Radiographic interpretation of malignant conditions

General Objective

Some definitions….

Radiopaque

This refers to the item that is being imaged, i.e. in our case a part of the patient, and means that it blocks the transmission of x rays.

Radiolucent

This refers to the item that is being imaged, i.e. in our case a part of the patient, and means that it permits the transmission of x rays.

Dense (Density)

In radiology this usually refers to the film, and refers to the ability of the film to block the transmission of light (i.e. blackness)

Well localized

The item being reported is limited to a specific area, and does not extend beyond that locality.

Well localized

Poorly localized

The item being reported is not limited to a specific area, and extends into surrounding anatomical sites.

Poorly localized

Well defined

The edges of the item being reported are reasonably sharp and clearly define the extent of the lesion.

Well defined

Poorly defined

The edges of the item being reported are not sharp. The actual borders and thus the exact extent of the lesion are not clearly defined.

Poorly defined

The lesion may thus be well localized and well defined

or well localized, but poorly defined

or poorly localized and poorly defined

but generally not poorly localized and well defined

Corticated

The entity being reported is not only well defined, but has a cortex, i.e. an osseous border, seen as a thin white line.

Corticated

Multilocular

The entity being reported is usually well defined and has a cortex, i.e. an osseous border, seen as a thin white line, but is partially or totally subdivided into several loculi.

Multilocular

Loculus, loculi: the diminutive of locus.

Locus, loci: a place or position

Multilocular

Thus, multilocular implies several small places. As we use it, they are joined places.

Multilocular

Osteitis vs Osteomyelitis

Both terms mean that there is inflammation of bone.

Osteitis

inflammation of bone, involving the haversian spaces, canals, and their branches, and generally the medullary cavity, and marked by enlargement of the bone, tenderness, and a dull aching pain.

Dorland’s Illustrated Medical Dictionary 29th ed.

Osteomyelitis

inflammation of bone caused by infection, usually by a pyogenic organism, although any infectious agent may be involved. It may remain localized or may spread through the bone to involve the marrow, cortex, cancellous tissue, and periosteum.

Dorland’s Illustrated Medical Dictionary 29th ed.

Osteitis

inflammation of bone that remains localized, and may be more of a painful inconvenience

Osteitis

Osteomyelitis

Osteitis

Rarefying Osteitis

Sclerosing Osteitis

Rarefying Osteitis(Periapical lesion U. of K.)

Inflammation of bone that results in the removal of bone. The term is not a diagnosis, but a radiologic interpretation that includes abscess, cyst and granuloma.

Rarefying Osteitis (periapical lesion at UK)

Sclerosing Osteitis

I use the term sclerosing osteitis, i.e. inflammation of bone (osteitis) that causes sclerosis.

Sclerosing (or condensing) Osteitis

Sclerosing Osteitis

Periosteal Reaction

Any involvement of the periosteum by a pathological process that results in the deposition of periosteal new bone.

Inflammation of the Jaws and Periosteal Reactions Osteomyelitis

Periostitis

Healing

Anemia

Sessile

Sarcoma

Sarcoma

Orthogonal

Periapical Radiolucency

This is merely a description of a finding, and should better be stated as a periapical radiolucent area or line. It does not denote disease. e.g. the maxillary sinus could be a periapical radiolucent area, as could the mental foramen.

What is that radiologist really saying?

Well defined andCorticated

Well localized

Well localized

The radiologist infers that the appearance is consistent with a slow non-invasive growth, and thus that this is benign.

Poorly localized

Poorly localized

The radiologist infers that the appearance is consistent with a faster and invasive growth, and thus that this is malignant, or a spreading infectious/inflammatory lesion.

Well defined

Well defined

The radiologist infers that the appearance is consistent with a slow non-invasive growth, and thus that this is benign.

Poorly defined

Poorly defined

The radiologist infers that the appearance is consistent with invasive growth, and thus that this is malignant, or infectious/ inflammatory lesion.

Corticated

Corticated

The radiologist infers that the appearance is consistent with a slow non-invasive growth, and thus that this is benign.

Multilocular

Multilocular

The radiologist infers that the appearance is consistent with a slow non-invasive growth, is not fluid-filled, and that this is a benign, non-cystic growth, i.e. a benign neoplasm.

Clinical Examination

• Radiographs are prescribed when the dentist thinks that they are likely to offer useful diagnostic information that will influenced the TREATMENT plan.

• Clinical information should be used first to select the type of radiographs and later to aid in their interpretation.

ADQUIRING APPROPRIATE DIAGNOSTIC IMAGES

Quality of the Diagnostic Image

• Is the image distorted?• Are the contrast and density adequate?

Clinical Examination

ADQUIRING APPROPRIATE DIAGNOSTIC IMAGES

Quality of the Diagnostic Image

Number and Type of Available Images

• Initially the clinical examination indicates the number and types of films required. The interpretation of these films in turn may suggest additional imaging.

• Advanced techniques available (CBCT, MRI, ultrasound, CT, etc)

Clinical Examination

ADQUIRING APPROPRIATE DIAGNOSTIC IMAGES

Quality of the Diagnostic Image

Number and Type of Available Images

Viewing Conditions

• Ambient light in the viewing room should be reduced.• Intraoral radiographs should be mounted in a film holder.• Light from the viewbox should be of equal intensity across viewing surface• Use of magnifier

Image Analysis

• Systematic Radiographic Examination

- Profound knowledge of normal anatomy and normal variations.- Best learning method Indentify NORMAL anatomy in every film- Do not limit your attention to only one particular are on the film

• Intraoral Images

- Periapical films before bitewings- Same sequence- Bone first, bone of the alveolar process second, dentition last

• Extraoral radiography Panoramic films (lateral skull projections)

Bone

Alveolar Bone

Dentition

Analysis of the Intraosseous Lesions

The preferred method of radiographic interpretation is STEP by STEP

This procedure helps ensure recognition and collection of all theinformation contained in the image and in turn improves theaccuracy of the interpretation.

1. Localize the abnormality

- Localized or Generalized- Position in the jaws- Single or multifocal- Size and shape

Analysis of the Intraosseous Lesions

1. Localize the abnormality

- Localized or Generalized- Position in the jaws- Single or multifocal- Size

2. Assess the periphery and shape

- Well defined ?- Corticated ?- Borders- Shape

Analysis of the Intraosseous Lesions

Step 2 Assess the periphery and shape

Corticated

Well defined

Analysis of the Intraosseous Lesions

Step 2 Assess the periphery and shape

Non - Corticated

Well defined

Analysis of the Intraosseous Lesions

Step 2 Assess the periphery and shape

Step 3: Analyze the internal structure

- Totally radiolucent- Totally radiopaque- Mixed density

Analysis of the Intraosseous Lesions

Step 3: Analyze the internal structure

- Totally radiolucent- Totally radiopaque- Mixed density

Analysis of the Intraosseous Lesions

Step 3: Analyze the internal structure

- Totally radiolucent- Totally radiopaque- Mixed density

Analysis of the Intraosseous Lesions

Step 3: Analyze the internal structure

- Totally radiolucent- Totally radiopaque- Mixed density

Analysis of the Intraosseous Lesions

Step 4: Analyze the effects of the lesion on surround structures

- Teeth, lamina dura, and periodontal ligament space- Surrounding bone density and trabecular bone pattern- Inferior alveolar canal and mental foramen- outer cortical bone and periostial reactions

Analysis of the Intraosseous Lesions

Step 4: Analyze the effects of the lesion on surround structures

- Teeth, lamina dura, and periodontal ligament space- Surrounding bone density and trabecular bone pattern- Inferior alveolar canal and mental foramen- outer cortical bone and periostial reactions

Analysis of the Intraosseous Lesions

Step 4: Analyze the effects of the lesion on surround structures

- Teeth, lamina dura, and periodontal ligament space- Surrounding bone density and trabecular bone pattern- Inferior alveolar canal and mental foramen- outer cortical bone and periostial reactions

Analysis of the Intraosseous Lesions

Step 4: Analyze the effects of the lesion on surround structures

- Teeth, lamina dura, and periodontal ligament space- Surrounding bone density and trabecular bone pattern- Inferior alveolar canal and mental foramen- outer cortical bone and periostial reactions

Analysis of the Intraosseous Lesions

Step 4: Analyze the effects of the lesion on surround structures

- Teeth, lamina dura, and periodontal ligament space- Surrounding bone density and trabecular bone pattern- Inferior alveolar canal and mental foramen- outer cortical bone and periostial reactions

Analysis of the Intraosseous Lesions

Step 5: Formulate a radiographic interpretation

Decision 1 Normal Abnormal

Decision 2 Developmental Acquired

Decision 3 Classification: Cyst, benign tumor, malignant tumor, etc..

Decision 4 Ways to proceed: Further imaging, treatment, biopsy, or observation

RADIOLOGY REPORT