Osteoradionekrose der Mandibula

Mandibular osteoradionecrosis (ORN) is more common after radiation therapy for head and neck malignancies due to the superficial position of the mandible, which exposes it to high radiation. The maxilla can also be involved, but this is less frequent.

Epidemiology

Mandibular ORN may occur in ~20% (5-37%) of patients .

Pathology

Mandibular ORN typically occurs in a patient who has received a dose of >60 Gy . Osteoradionecrosis changes may occur within a year of therapy.

Radiographic features

Features include :

• cortical destruction that is ill-defined resulting in a mixed sclerotic-lucent pattern
• sequestration, especially of the buccal bone
• an absence of soft tissue mass is an important feature to differentiate it from neoplastic recurrence but the presence of soft tissue does not exclude ORN

Treatment and prognosis

Conservative treatment is initially medication only (e.g. pentoxifylline, vitamin E) but more severe cases may require hyperbaric oxygen therapy and/or debridement. Some patients will require resection and reconstruction of the mandible .

Complications

• pathological fractures
• infection 
• radiation-induced neoplasia

Differential diagnosis

• medication-related osteonecrosis of the jaw (MRONJ)
• chronic osteomyelitis
• malignancy

Siehe auch:

• Tumoren der Mandibula
• lytische Läsionen der Mandibula