Spontaneous middle fossa encephalocele

ABSTRACT

@#A 48-year old man presented with a unilateral right hearing loss of four months’ duration. A right middle ear effusion was noted on physical examination. Endoscopic examination of the nasopharynx was unremarkable. Due to the duration of the symptoms, myringotomy with ventilation tube insertion was offered as a treatment option. Upon myringotomy, clear pulsatile liquid flowed out of the incision. More than 5 cc of liquid was collected which continued to flow out despite active suctioning. Due to the realization that the liquid most likely represented cerebrospinal fluid, insertion of a ventilation tube was not performed. The ear canal was packed with sterile cotton, and the patient was given a short course of acetazolamide to decrease CSF production. Upon further questioning, the patient did not have any prior head trauma. The patient then underwent both computerized tomographic (CT) imaging and magnetic resonance imaging (MRI) of the temporal bone to look specifically for evidence of a dehiscence in the middle fossa plate (tegmen) or posterior fossa plate, as well as the presence of a meningoencephalocele.