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RADIOGRAPHIC PATHOLOGY OF THE
HEAD AND NECKDr. Parish P. SedghizadehDiplomate, American Board of Oral & Maxillofacial PathologyAssistant Professor, University of Southern California –School of Dentistry and Center for Craniofacial Molecular BiologyDivision of Diagnostic Sciences; Orofacial Pain & Oral Medicine Center
Looking for abnormalities: Requires knowledge of normal anatomy first, what constitutes a good film or image, and why the imaging study is being done clinically.
Radiolucency , Opacity, or mixed…
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Differential Diagnostic process: Based on normal anatomy, then identifying abnormality as possibly an Odontogenic Cyst/Tumor, Neurovascular lesion, Non-Odontogenic Cyst/Tumor, or other condition…depending on the epicenter relationship to anatomic structures like the IA Canal.
Neurovascular Lesion• Benign:
– Neurofibroma– Neuroma
– Hemangioma
• Malignant:– Neurofibrosarcoma
– Neurogenic Sarcoma– Angiosarcoma
Differential Diagnosis:Mandibular Radiolucencies
Within the IA Canal
Differential Diagnosis:Mandibular Radiolucencies
Above the IA Canal (excludes infections• Odontogenic Cysts causing apical lesion)
– Dentigerous Cyst (often contains crown of impacted tooth)– Odontogenic Keratocyst (OKC)– Lateral Periodontal Cyst– Periapical Cyst– Calcifying Odontogenic Cyst (COC)
• Odontogenic Tumors– Ameloblastoma– Adenomatoid Odontogenic Tumor – Calcifying Epithelial Odontogenic Tumor (mixed lucency-
opacity)– Odontoma (central opacification with peripheral lucency)– Odontogenic Myxoma (multi-locular lucency)
Dentigerous (Developmental) Cyst
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Dentigerous (Developmental) Cyst
Dentigerous (Developmental) Cyst
Odontogenic Myxoma
Lateral Periodontal Cyst Odontogenic Keratocyst
Residual Cyst Calcifying Odontogenic Cyst
Odontomas (compound)
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Odontoma (complex)
Periapical Cemento-Osseous Dysplasia
Differential Diagnosis:Mandibular Radiolucencies
Below the IA Canal• Bone Tumors
– Metastatic Carcinoma– Osteosarcoma
• Bone Cysts– Stafne bone defect (not a true cyst, but actually a salivary gland
depression in the bone – no Tx, follow)– Traumatic Bone Cyst– Aneurysmal Bone Cyst (ABC)
• Bone Reactive / Inflammatory– Osteomyelitis– Giant Cell Reaction
* Except for the Stafne defect, most of the lesions above often appear above the IA canal also, highlighting the fact that most lesions in the lower jaw occur above the IA canal.
Size Difference?
Size Difference?
Stafne Defect
NO! CT scan or periodic radiographic evaluation
Some small but important opacities…
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Idiopathic Osteosclerosis
(formerly Condensing Osteitis )
Sialolith
Calcified (mineralized) Lymph Nodes (tuberculosis)Calcified (mineralized) Atherosclerotic Plaques of Carotid Artery
THE ROLE OF ADVANCED IMAGING
IN DIFFERENTIATING BONE PATHOSES WITH OSTEOGENIC POTENTIAL,
such as in cases demonstrating new periosteal bone formation
PERIOSTEAL REACTIONS IN THE FORM OF NEW BONE
FORMATION- Osteomyelitis
- (proliferative periostitis)
- Osteosarcoma- Metastatic Carcinoma- Langerhans Cell Disease
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Periosteal Reactions• Varying etiopathogenesis
– Ranging from reactive to neoplastic
• Result is varying osteoblastic (forming) and osteoclastic (resorbing) activity physiologically/molecularly that is evident histopathologically also
• Demonstrates radiographic appearance likened to an “onion-skin” or “hair-on-end”pattern
Periosteal Reactions• Varying etiopathogenesis
– Ranging from reactive to neoplastic
• Result is varying osteoblastic (forming) and osteoclastic (resorbing) activity physiologically/molecularly that is evident histopathologically also
• Demonstrates radiographic appearance likened to an “onion-skin” or “hair-on-end”pattern
• Clinically may demonstrate cortical osseous expansion, with or without tenderness depending on factors such as etiology and patients’ pain perceptions
• Definitive diagnosis may require clinical, radiographic, and histologic/ immunohistochemical correlation in many cases
Periosteal Reactions Conditions in which new periosteal bone formation
may be a feature• Osteomyelitis
- Proliferative Periostitis (Garrè’s)
• Osteosarcoma
• Metastatic Carcinoma
• Langerhans Cell Disease
Osteomyelitis –Proliferative Periostitis
• Hypothesized that acute osteomyelitis, or inflammation of medullary bone, which is mainly lytic in nature, (from infection, trauma, etc…) spreads to the periosteum
• Inflammatory cytokines then stimulate cortical resorption, while inflammatory exudate also lifts the periosteum and induces new bone formation which occurs parallel/lamellar to cortex, accounting for unique presentation
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Osteosarcoma
• Periosteal, Parosteal, and Gnathic in H&N• Rare cases associated with Paget’s
disease and Cemento-Osseous dysplasia • Radiolucent, radiopaque, or mixed
radiographic appearance• Lytic, loss of lamina dura, widening of
PDL, destruction of adjacent structures, and ragged and ill-defined margins may be seen classically
• Disrupted and disorganized periosteum may appear “hair-on-end” or “sunburst”
• Intact periosteum, more rarely, may show an “onion-skin” pattern, presumably mediated by molecular and chemical factors released from tumor cells and immune cells
• Bone Morphogenic Protein, Alkaline Phosphatase, Osteocalcin, Endothelin, and various growth factors
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Metastatic Carcinoma• Variable radiographic appearance, with
polymorphous shape and irregular, ill-defined margins usually
• However, similar to previous conditions, metastatic carcinoma can also produce a periosteal reaction in the form of new bone formation, particularly prostate and breast cancers
• In vitro cell culture studies have shown prostatic acid phosphatase and its substrate α-glycerophosphate stimulate calcification and osteogenesis in prostatic cases
Langerhans Cell Disease• Growing evidence indicates this is a
neoplastic process, and many investigators favor malignancy of Langerhans cells as opposed to histiocytes (CD1a vs.CD68)
• Intraosseous lesions may result in radiographic appearance of teeth with unsupported bone, often termed “teeth floating in space”
• New periosteal bone formation similar to aforementioned inflammatory (cytokine) neoperiostosis may be a feature
• Mainly children and young adults affected
•
CD1a stain
Langerhans cell diseaseCopyright © 2003, Elsevier Science (USA). All rights reserved.
THE ROLE OF ADVANCED IMAGING IN
DIFFERENTIATING BETWEEN BONE PATHOSES
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