Diffusion tensor imaging and auditory tractography to evaluate cochlear implant candidacy: a pilot study.

BACKGROUND: Conventional radiological evaluation does not evaluate the functional status of the auditory pathway in patients scheduled for cochlear implantation (CI). OBJECTIVES: Determine the value of diffusion tensor imaging [DTI] in the preoperative evaluation of some patients scheduled for CI. MATERIAL AND METHODS: Patients with profound SNHL and inner ear and/or cochlear nerve anomalies or long standing SNHL were selected. They underwent conventional MRI images of the brain in three orthogonal planes, MR arterial spin labelling (ASL), perfusion, and DTI auditory tractography to determine functional status of the auditory pathways. RESULTS: Ten patients were included. Seven with bilateral SNHL, one with fluctuating hearing loss and one with long standing single sided deafness. In 8 patients the auditory pathway could be traced and functional maps could determine the side of possible better function. In the patient with progressive hearing loss DTI revealed major central pathway problems and CI was discouraged. In the patient with SSD, DTI revealed a robust intact pathway and CI was advised. CONCLUSIONS: DTI and auditory tractography can help in outlining the functional integrity of the 33auditory pathway and assist in decision making before CI.

In Patients with Unexplained Non-Epidemic Recurrent Meningitis a Direct Communication between the Subarachnoid Space and the Outside Must Be Sough.

Cerebrospinal fluid (CSF) rhinorrhea is not an uncommon condition, and it may lead to recurrent attacks of meningitis. The detection of the leakage site is an essential part of the investigations performed for the patient. In some cases, an anterior skull base site cannot be detected despite continuous leakage. In these cases, a more distal site must be sought. Furthermore, in some cases, the leakage occurs in the temporal bone. In such patients, a history of hearing loss or previous ear complaints indicates a hidden CSF otorhinorrhea. We present two adult cases of congenital hearing loss due to unilateral inner ear anomalies who presented later in life with repeated meningitis attacks and CSF otorhinorrhea.