抄録
A case of an isolated bone fragment in the ethmoid sinus was reported. A 37-year-old male visited our clinic complaining of nasal obstruction and nasal discharge. An X-rayexamination revealed the thickening of the mucous membrane of the maxillary sinus, cloudinessof the ethmoid sinus, and a small round shadow in the right ethmoid sinus. Under the diagnosis of chronic paranasal sinusitis, the surgical operation was performed and an isolated bone fragment, located adjacent to the lamina papyracea was found. Because of the extremely rare occurance of an isolated bone fragment in the ethmoid sinus, the origin and formation of this fragment was discussed.
