[The characteristics of CT scan and MRI images of middle ear adenomas].

Objective: To analyze characteristics of CT scan and MRI images of middle ear adenomas,and provide pre-operation diagnosis and differential diagnosis combined with clinical manifestation. Method: Retrospective analysis of 8 cases of middle ear adenomas which were diagnosed and treated with surgery in Beijing Tongren Hospital between 2004 and 2014, patients' complain, clinical manifestation, physical examination, pure tone analysis, CT scan and MRI images were collected. Result: A total of 8 cases were included in this study with 5 females and 3 males. Age of onset ranged from 21 to 51 years old, with an average age of 37.5 years old, and middle age of 37 years old. All patients suffered from single side middle ear adenomas, 5 of left side and 3 of right side. All 8 patients suffered from hearing loss with tinnitus or stuffy feelings, 2 cases with otalgia, 1 with facial nerve paralysis. Physical examination showed 5 cases of bulging of tympanic membrane, 2 cases of out growth of mass into the external ear canal, and 1 with normal tympanic membrane. CT scan of 7 patients showed mass in tympanum and mastoid, with packaged ossicular chain and with no significant bone damage. 2 cases showed out growth of mass into the external ear canal, and 1 case showed limited mass in middle tympanum. MRI images of 5 cases showed equal T1 and T2 signals with intensifying in tympanum. Long T1 or equal T1 and long T2 signal in mastoid showed obstructive inflammation. Conclusion: Characters of middle ear adenomas includes mass in tympanum without bone damage in CT scan, and equal T1 and T2 signal with significant intensifying in tympanum in MRI images. Combined with clinical manifestation, this radiological information may provide benefit for pre-operation diagnosis.