[Stapedial reflex in nontumor retrocochlear pathology]

Area of Science:

• Audiology
• Neurotology
• Diagnostic Imaging

Background:

• The stapedius reflex is a diagnostic tool used in audiology.
• Retrocochlear disorders, including acoustic neuromas and endocochlear diseases, require accurate diagnosis.
• Electrophysiologic and neuroradiologic methods are crucial for assessing these conditions.

Purpose of the Study:

• To evaluate the diagnostic parameters of the stapedius reflex in patients with retrocochlear and non-tumoral conditions.
• To compare stapedius reflex results with those from acoustic neuromas and endocochlear diseases.
• To determine the sensitivity and specificity of the stapedius reflex for retrocochlear pathologies.

Main Methods:

• Studied 55 patients with retrocochlear and non-tumoral diagnoses.
• Utilized electrophysiologic tests: Brainstem Auditory Evoked Response (BERA) and Electrocochleography.
• Employed neuroradiologic explorations: Computed Axial Tomography (TAC), Meato-cisternography, and Nuclear Magnetic Resonance (NMR).

Main Results:

• The stapedius reflex test demonstrated moderate sensitivity and low specificity for retrocochlear disorders.
• A high rate of false negatives (30%) was observed.
• The test was positive in 95% of acoustic neuroma cases and 74% of endocochlear disease cases.

Conclusions:

• The stapedius reflex has limited utility as a standalone diagnostic test for retrocochlear pathologies due to its low specificity and high false-negative rate.
• While showing high positivity in acoustic neuromas, its effectiveness is diminished in other retrocochlear conditions.
• Further investigation with complementary electrophysiologic and neuroradiologic methods is essential for accurate diagnosis.