Radiation Necrosis of the Lateral Skull Base and Temporal Bone

Radiation therapy plays a critical role in the treatment of malignancies involving the head and neck. Although the therapeutic effects of ionizing radiation are achieved, normal tissues are also susceptible to injury and significant long-term sequelae. Osteoradionecrosis of the temporal bone (ORNTB) is among the many complications that can arise after therapy. ORNTB is a debilitating and potentially lethal condition that continues to challenge patients and treating physicians. Herein, we review the pathophysiology, presentation, work-up, and management of ORNTB.

Osteoradionecrosis of the Temporal Bone: An Evidence-Based Approach

OBJECTIVES

To perform a systematic review evaluating etiologies, associated complications, and management of osteoradionecrosis of the temporal bone (ORNTB).

METHODS

The authors searched the PubMed, Embase, and Cochrane Library databases for relevant literature. Patient demographics, etiologies, treatments, and other clinical characteristics were obtained. Treatment success was defined as resolution of symptoms at last follow-up. Results were reported using the preferred reporting systems for systematic reviews and meta-analysis (PRISMA) guidelines.

RESULTS

Thirty-eight studies encompassing 364 patients with ORNTB were identified. The most common etiologies necessitating radiotherapy included: nasopharyngeal carcinoma (n = 133 [36.8%]), parotid tumors (n = 73 [20.2%]), and external auditory canal pathology (n = 59 [16.3%]). The mean dose of radiation was 58.0 Gy. The mean lag time between radiotherapy and osteoradionecrosis (ORN) symptoms was 7.9 years. The most common presenting symptoms were purulent otorrhea (33.3%), hearing loss (29.1%), and otalgia (17%). ORNTB complications included tympanic membrane perforation (n = 102 [63.8%]) and chronic otitis media (n = 16 [10%]). Treatments included lateral temporal bone resection (n = 99 [28.3%]), conservative treatment (n = 92 [26.3%]), and mastoidectomy (n = 82 [23.5%]) with 90.9, 89.13, and 59.76% considered successful, respectively.

CONCLUSIONS

ORNTB is a rare complication of radiotherapy that may present years after initial radiation exposure. Management should be aimed at relief of presenting symptoms and treatment of ORNTB associated complications. Both conservative and surgical measures may adequately control the disease process and symptomatology; however, randomized controlled studies comparing treatments would serve to further corroborate these findings.

Endoscopic transpterygoidal repair of a large cranial defect with cerebrospinal fluid leak in a patient with extensive osteoradionecrosis of the skull base: case report and technical note

BACKGROUND

Endoscopic endonasal techniques have recently become the method of choice in dealing with cerebrospinal fluid leak involving the anterior cranial fossa. However, most surgeons prefer an intracranial approach when leaks involve the middle cranial fossa. This case report illustrates the possibilities of using endoscopic techniques for cerebrospinal fluid leaks involving the middle fossa.

CASE REPORT

A 37-year-old male patient presented with multiple areas of cranial defect with cerebrospinal fluid leak due to osteoradionecrosis following radiation for nasopharyngeal carcinoma 4 years earlier. Clinical examination showed involvement of all cranial nerves except the IInd and XIth nerves on the left side. A prior attempt to repair the cerebrospinal fluid leak with craniotomy was not successful.

CONCLUSION

This case demonstrates the successful endoscopic repair of a large cranial defect with cerebrospinal fluid leak.

[Osteoradionecrosis of the temporal bone]

INTRODUCTION

Radiotherapy is an effective, modern method of treating malignant neoplasms of head and neck and also intracranial tumours. Technological development and computerization of equipment used in radiotherapy enabled introduction of modern methods of treatment allowing decrease the risk of postradiation complications but not eliminating them completely. Postradiant necrosis of temporal bone that is osteoradionecrosis (ORN) is a quite well known complication of radiotherapy of head and neck tumours. Secretory otitis media, conductive deafness, excretion of sequesters through external auditory canal, inflammation and atresia of external auditory canal are common findings during examination. Cases of disseminated osteoradionecrosis need to be qualified for operation due to potential intratemporal and intracranial complications. Radical excision of necrotic tissue gives possibility of parallel cochlear implantation among patients with total bilateral deafness, which is a consequence of radiotherapy.

AIMS

Aim of this study was clinical and epidemiological analysis of consequences and complications inside temporal bone which occurred after radiotherapy in the head and neck area. Conservative and surgical treatment possibilities according to progression of postradiant changes and severity of ailments were analyzed. Circumstances of conducting lateral petrosectomy with parallel cochlear implantation in case of osteoradionecrosis proceeding with total bilateral deafness were highlighted.

MATERIAL AND METHODS

Retrospective analysis of 12 patients treated in the Department of Otolaryngology at the Medical University of Warsaw in 2000-2010 for postradiant consequences and complications inside the temporal bone was performed. The diagnosis of osteoradionecrosis was based on clinical ENT examination including meticulous microscopic examination, audiologic evaluation and CT scans of temporal bone.

RESULTS

The group consisted of 5 men and 7 women. In 8 patients changes were unilateral and in 4 - bilateral. In total, 16 cases (ears) of osteoradionecrosis in the area of temporal bone were analyzed. Patients were mainly complaining about hearing loss or deafness, tinnitus, otalgia, otorhoea, feeling of fullness and distension in the ear. Presence of effusion in the middle ear was an indication for ventilation tube insertion. Cases of ORN potentially endangered by further complications needed surgical treatment, therein lateral petrosectomy. Case of osteoradionecrosis proceeding with total bilateral deafness needed a concurrent cochlear implantation. Only the patients with diffuse osteoradionecrosis confirmed by CT scans ere qualified for surgery.

CONCLUSIONS

Radiotherapy of head and neck tumours is charged with risk of complications, both early and appearing later after therapy. Osteoradionecrosis is found many years after radiation and the course of illness is repeatedly tricky and potentially life-threatening. In the face of complications resulting from the essence of illness surgical treatment, therein lateral petrosectomy is necessary. Complications of radiotherapy cannot eliminate it as a method of independent treatment nor combined with other methods.

CSF Otorrhea Resulting from Osteoradionecrosis of the Temporal Bone in a Patient with Recurrent Meningioma

Osteoradionecrosis of the temporal bone is a very rare but potentially lethal complication of radiotherapy for head and neck or skull base tumors. Only two cases of osteoradionecrosis of the temporal bone complicating cerebrospinal fluid (CSF) otorrhea have been reported in the literature. This report describes a case of CSF otorrhea and osteoradionecrosis of the temporal bone in a patient with meningioma who was treated with tympanomastoid surgery and autologous fat obliteration in the mastoid.

Surgical treatment of osteoradionecrosis of the temporal bone in patients with nasopharyngeal carcinoma

Objective:

To investigate methods of treating diffuse osteoradionecrosis of the temporal bone in cases of nasopharyngeal carcinoma, following radiotherapy.

Study design:

Retrospective.

Methods:

Fourteen post-irradiation nasopharyngeal carcinoma patients (n = 14 ears) with diffuse osteoradionecrosis received surgical treatment from March 1994 to May 2005. The patients underwent radical mastoidectomy (five ears), extensive radical mastoidectomy (one ear), or radical mastoidectomy and obliteration with local vascularised fascia flaps (eight ears).

Results:

Six ears fully recovered; two ears were still infectious but sequestrum had not re-formed; five ears (50 per cent) still had repeated suppuration and did not epithelialise; and one ear had local re-formation of sequestrum requiring periodic dressing changes.

Conclusion:

Diffuse osteoradionecrosis of the temporal bone following radiotherapy for nasopharyngeal carcinoma is difficult to treat surgically. The main objective of surgery is to facilitate drainage and to prevent complications. Radical mastoidectomy and obliteration with local vascularised flaps is an effective method.