In Meniere's disease, the electrocochleography (EcochG) finding that supports endolymphatic hydrops is:
- A Absence of summating potential
- B Prolonged wave V latency on ABR
- C Elevated SP/AP ratio greater than 0.4 ✓
- D Type B tympanogram
Correct answer: C. Elevated SP/AP ratio greater than 0.4
Explanation
Electrocochleography (EcochG) in Meniere's disease shows an elevated summating potential to action potential (SP/AP) ratio greater than 0.4 (or 40%), indicating endolymphatic hydrops. The summating potential is generated by the hair cells and is abnormally enlarged when the basilar membrane is displaced by hydrops, reflecting the increased pressure within the endolymphatic space. ABR wave V latency and tympanograms are not diagnostic of Meniere's.
Reference: Dhingra Diseases of Ear, Nose and Throat, 7th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.