Oval window perilymph fistula in child with recurrent meningitis and unilateral hearing loss

Abstract

A 2-year-old boy presented to Ears, Nose and Throat (ENT) surgeons with unilateral hearing loss. Following a prodrome of upper respiratory tract infection (URTI), he developed two episodes of pneumococcal meningitis in quick succession. This case demonstrates an unusual cause of perilymph fistula diagnosed on imaging and confirmed surgically. He had failed the Newborn Hearing Screening Programme and was therefore referred to audiology, who confirmed profound sensorineural hearing loss in the right ear. MRI showed incomplete partitioning (type 1) of the right cochlea, suggesting cerebrospinal fluid (CSF) leak from the region of the stapes. Exploratory tympanotomy confirmed this, and proceeded to CSF leak repair, obliteration of the Eustachian tube, subtotal petrosectomy, abdominal fat grafting and blind sac closure. Although middle ear effusions are common; particularly in children with recent URTI, the possibility of otogenic CSF leak needs to be considered, especially in cases of recurrent meningitis.

Keywords: congenital disorders; ear, nose and throat/otolaryngology; radiology.

Figure 1

Axial 3D T2 WI (Fast Imaging Employing Steady-state Acquisition (FIESTA) sequence) shows malformed right labyrinth with cystic appearance of the vestibule and the cochlea in keeping with common cavity (white arrow). The stapes is surrounded by fluid and is connected with a markedly enlarged oval window (arrowhead). There was fluid filling the tympanic cavity, mastoid and along the course of a patent Eustachian tube (double arrow). Note normal inner ear anatomy on the left.

Figure 2

High resolution petrous bone CT confirm enlargement of the oval window (arrow in A), malformed labyrinth and fluid filling the tympanic cavity and mastoid cells (arrow in B).

Figure 3

Clearance of adhesions from the oval window resulted in the stapes being mobilised and removed to allow packing of the defect.