[A case of chondroblastoma arising from the temporal bone].

A 33-year-old male sustained hearing disturbance in the left ear that exacerbated over a period of three years. The patient was referred to the department of otorhynolaryngology for severe stenosis of the left external auditory canal, where neuroimaging study revealed a huge tumor in the left temporal fossa. On first examination, he showed a significant facial nerve paresis and conductive hearing loss. CT scans identified a 4.5×4.5×4.5 cm mass with intralesional calcification and extensive bony destruction in the squamous and petrous parts of the temporal bone and middle cranial fossa floor. MR imaging demonstrated the tumor of heterogenous intensity on T1-and hypointensity on T2-weighted image. The patient underwent gross total resection of the lesion via frontotemporal craniotomy. The bony and ligamentous structures around the temporomandibular joint appeared mostly intact and did not need any reconstructive surgery after tumor resection. Postoperatively the patient's facial nerve paresis showed a transient exacerbation which resolved gradually, while hearing disturbance did not improve. Histological findings of the tumor were consistent with the qualities of chondroblastoma. We should assume chondroblastoma as differential diagnosis when we encounter a temporal bone tumor that is curable by surgical resection.