Bilateral spontaneous cerebrospinal fluid otorrhea.

We present a rare case of bilateral cerebrospinal fluid (CSF) otorrhea via multiple bony defects in the left tegmen and a single defect with the herniated brain tissue on the right side. Initially, the patient complained of left hearing loss and fullness and was diagnosed with serous otitis media. After myringotomy, the pulsating watery discharge suggested CSF otorrhea. Five months after surgical repair of the left side, right-side CSF leakage occurred. The right side was repaired surgically, and the patient recovered without incident. From our findings and a review of the literature, we postulate that bilateral CSF otorrhea resulted mainly from the thinness of the tegmen because of well-pneumatized mastoid air cells and the weakness of the dura after chronic inflammatory changes. In case of spontaneous CSF otorrhea, the roof of tegmen should be assessed bilaterally with care using radiologic examinations so as not to overlook a subclinical condition on the contralateral side.