Osteoradionecrosis of the hyoid bone after intra-arterial chemoradiotherapy for oropharyngeal cancer: MR imaging findings

Abstract

BackgroundOsteoradionecrosis (ORN) of the hyoid bone sometimes induces severe front neck infection and can cause laryngeal stenosis and carotid rupture. Although ORN of the hyoid bone is known to be a complication of chemoradiotherapy for head and neck cancer, there has been no basis for its evaluation. Our purpose is to present the clinical and MR imaging features of ORN of the hyoid bone.MethodsThe study group comprised patients with advanced oropharyngeal cancer treated with targeted intra-arterial cisplatin infusion with concomitant radiotherapy. ORN of the hyoid bone was identified on the basis of decreased signal intensity of the bone marrow on T1WI images. Signal intensity on T2WI images was used to distinguish between inflammation and fibrosis.ResultsA total of 39 pre-treatment MR images and follow-up MR images were reviewed. ORN of the hyoid bone were detected in 30% of patients after treatment, with 23% of them showing inflammation and 7.7% fibrosis. Two patients developed severe neck infection and received antibiotics and underwent surgical intervention by tracheostomy and resection of the hyoid bone.ConclusionOur MR imaging study showed that ORN of the hyoid bone is not particularly rare in patients with oropharyngeal cancer treated with chemoradiotherapy. Clinicians should evaluate images carefully to prevent the development of severe complication due to infection associated with ORN of the hyoid bone.

Microstructure of the hyoid bone based on micro-computed tomography findings

“…Notably, in patients with head and neck cancer after radiotherapy and chemotherapy, there are changes in the trabecular bone of the hyoid bone, suggesting that radiotherapy and chemotherapy might lead to issues such as hyoid bone complications. [ 24 ]…”

Tc-99m hydroxymethylene diphosphonate scintigraphy, computed tomography, and magnetic resonance imaging of osteonecrosis in the mandible: Osteoradionecrosis versus medication-related osteonecrosis of the jaw

“…Imaging findings are unclear both in the early stages of ORN and when the disease is advanced 111213. Although the radiological findings are nonspecific, they do appear to play a role in the management of MRONJ 17.…”

“…MR imaging is useful for the diagnosis of bone marrow disease, and necrosis is usually detected as areas of decreased signal on T1WI 13. Krishnan et al2 reported that the earliest MR imaging finding of MRONJ was the loss of the normal T1 hyperintensity of fatty marrow in the mandible.…”

“…Regarding the reasons underlying the different imaging characteristics of MRONJ and ORN, we propose that periosteal bone proliferation on CT in association with ORN is rare because ORN is caused by radiation arteritis 111213…”

“…ORN is a pernicious complication of radiotherapy for head and neck carcinomas 10. The most common cause of ORN is radiation arteritis,111213 which leads to the onset of a hypocellular, hypovascular, and hypoxic environment. Jaws with MRONJ or ORN must be evaluated before any medical procedure is performed 9…”