Hear me out – tiny steroid implants for fighting meningitis-induced deafness
Reviewed by Thomas William Binnersley

Sensorineural hearing loss is the most common neurological complication of pneumococcal meningitis. Bacterial infiltration into the inner ear triggers inflammation, leading to cochlear fibrosis and sclerosis – damage that, in over a third of cases, affects both ears. Current Infectious Diseases Society guidelines recommend adjunct dexamethasone to mitigate this inflammatory process and, in turn, reduce rates of hearing loss. But what is the optimal way to deliver this steroid, I hear you ask? Eravcı and colleagues have repurposed an FDA-approved implant, originally designed for controlled-release dexamethasone administration in diabetic macular oedema, adapting it for cochlear application. In their study, they implanted this device into the right round window of 10 rats inoculated with intracisternal Streptococcus pneumonia, alongside a three-day course of intravenous ceftriaxone. A control group of six rats received a saline injection into their right round window plus antibiotics. The left cochleae in all rats remained untouched. Three months later, all rats were euthanised and their cochleae harvested for histological analysis. Their results showed a reduction in post-infective ossification in the basal turns, and reduced fibrosis in all turns, of the implanted cochleae. These suggest a reduced inflammatory response required for successful cochlear implant insertion in post-meningitic auditory rehabilitation. However, there was no apparent prevention of spiral ganglion damage, a factor that could ultimately limit cochlear implant effectiveness. Of course, key questions remain and we do not know whether these histological results translate to functional hearing improvements in humans. Additionally, no comparative data are presented for systemic or intratympanic steroid therapy in pneumococcal meningitis. Nevertheless, this study demonstrates the feasibility of cochlear-implanted dexamethasone devices and their potential to reduce meningitis-induced inflammation. Future researchers must now refine dosing strategies and establish whether this method offers superior outcomes over existing treatments.

Preventive Effect of Controlled-Release Dexamethasone on Cochlear Ossification in Meningitis Mode.
Eravcı FC, Kaplan Ö, Kılınç F, et al.
ANN OTOL RHINOL LARYNGOL
2025 [ePub ahead of print].