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[Clinical analysis of petrous bone cholesteatoma: characteristics, diagnosis and treatment].

OBJECTIVE
To explore the clinical characteristics, diagnosis and surgical management of petrous bone cholesteatoma.


METHOD
The data of 12 patients who underwent surgery for petrous bone cholesteatoma(PBC) were retrospectively analyzed with respects to the clinical characteristics, diagnosis and management.


RESULT
Seven cases were characterized by a long otitis media history, severe hearing loss, and facial paralysis. In contrast, 5 cases were characterized with the symptoms of facial paralysis, hearing loss and vertigo attack and the absence of early otorrhea history. Trans labyrinth approach was chosen for 2 cases,while trans labyrinth-cochlear approach for 10. Cochlea was involved in 10 cases, while internal auditory canal in 9 and semicircular canal in 11. Otoscope was used in 1 case. Four patients were treated by partial resection of petrous apex and ear canal closure with good results. After years of follow-up, three recurrence cases were operated for a second time. Simultaneous facial nerve anastomosis or decompression was performed. The function of facial nerve recovered from V-VI to Ill-IV (House and Brackmann grading) in 6 anastomosis cases and from IV-V to II- IlI in 3 cases of decompression.


CONCLUSION
Petrous bone cholesteatoma was characterized by severe hearing loss, and facial paralysis. Surgical approaches are decided according to the extent of lesion and hearing status. Our study indicated that otoscope would help to ensure a radical removal of the pathology in cases with deep involvement and restricted vision. Partial resection of petrous bone and ear canal closure could be effective solution for challenging cerebrospinal fluid otorrhea with large dural defects and protecting vital neurovascular structures.