The Potential Significance of Reversed Stapes Reflex in Clinical Practice in Idiopathic Intracranial Hypertension

BACKGROUND: Stapes reflex test is a method of evaluating the involuntary muscle contraction of the stapedius muscle in response to a high-intensity sound stimulus. The formation of this reflex involves the intact function of the 7(th) nerve, brain stem, 8(th) nerve, and middle ear. Due to ease of administration and information yielded, the stapedial reflex is considered one of the most powerful differential diagnostic audiological procedures. Numerous studies have remarked on the fluid communication between the intracochlear and intracranial spaces through the cochlear aqueduct. Currently, the potential significance of a noninvasive audiological technique in the discrimination of raised intracranial pressure constitutes a crucial topic of interest. METHODS: We have performed the pre-LP and post-LP detailed otorhinolaryngological investigations, including the detailed inspection, audiometric testing, tympanometry, and stapedial reflex in a total of four consecutive patients with IIH. RESULTS: We found that the stapedial reflex was bilateral absent initially in two of the patients. However, the second stapedial reflex investigations after LP showed reversal of the reflex responses in both of the patients. CONCLUSIONS: We suggest some hypotheses and propose some clinical applications. Future studies focusing on the potential utility of this reflex in the monitorization of IIH may provide crucial perspectives.