Osteoradionecrosis of the temporal bone: a case series

Abstract

Objective: To study osteoradionecrosis (ORN) of the temporal bone.

Study design: Retrospective case review.

Setting: Academic medical center.

Patients: Patients were included who had previously undergone radiation to the head and neck and then developed exposed necrotic bone within the ear canal that persisted at least 3 months.

Interventions: Patients were treated with a variety of modalities, including conservative therapy with antibiotic ear drops and in-office debridements, hyperbaric oxygen therapy, and surgery.

Main outcome measures: To describe the presentation and management of patients with temporal bone osteoradionecrosis.

Results: Thirty-three patients with temporal bone osteoradionecrosis were included. The most common site of primary tumor was the parotid gland (n = 11), followed by the nasopharynx (n = 7). The time to development of ORN varied between 1 and 22 years, with mean of 7.9 years. The mean radiation dose was 62.6 Gy to the primary tumor, 53.1 Gy to the affected temporal bone, and 65.2 Gy to the affected tympanic bone. The most common symptoms of ORN were otorrhea (n = 15), hearing loss (n = 13), and otalgia (n = 12). Fifteen patients had bacterial superinfection, most commonly Staphylococcus aureus (n = 9). Conservative therapy was successful at managing symptoms but not in eradicating exposed bone in most patients. Surgery was used for recalcitrant pain, infection, cholesteatoma, cranial neuropathies, and intracranial complications.

Conclusion: Osteoradionecrosis is a rare complication of radiation to the temporal bone. Management should be aimed at relief of symptoms, eradication of superinfection, and treatment of other commonly present radiation effects like cholesteatoma and hearing loss.

Figure 1

Lag Years (years from radiation until diagnosis of ORN) plotted against XRT dose. Higher doses of XRT are not associated with quicker development of ORN.

Figure 2

Arrows point to necrotic brown bone inferiorly in the EAC. Changes to the epithelium of the EAC can be seen including thinning and increased superficial vascularity.

Figure 3

More extensive exposed bone within the EAC. Squamous debris and thickening of the TM make it difficult to see any middle ear landmarks. The arrow points to a fistula to the TMJ.

Figure 4

Bubbles are seen in the EAC with jaw opening. CT shows a bony defect of the anterior wall of the EAC leading to the glenoid fossa.

Figure 5

Coronal CT scan from the same patient as Figure 1, showing bone loss inferiorly in the EAC.

Figure 6

Axial T2 MRI showing fluid throughout the right middle ear and mastoid cavity in association with ORN.

Figure 7

Audiometric data comparing pure tone average (PTA), speech recognition threshold (SRT), and word recognition score (WRS) in the ear with ORN versus the contralateral ear. The height of the bar is the mean, and the error bars show the standard deviation.

Figure 8

H&E stain, 600x magnification, showing necrotic bone and inflammation with neutrophils. Note the absence of osteocytes in osteocyte lacunae.

Figure 9

Proposed treatment algorithm for osteoradionecrosis