electrocochleogram

Cochlear electrograms use the characteristics of the cochlear action potential (AP) response threshold close to the hearing threshold to objectively evaluate the hearing threshold of difficult partners. It is the most accurate method to identify the location of deafness (conduction, cochlear or worm). Under the stimulation of sound, the sound waves are transmitted from the vestibular window to the cochlea, causing the movement of the basement membrane, causing the cilia of the outer hair cells to be bent due to the scissor movement, forming a local current change at the top of the hair cells, and converting the mechanical energy into electrical energy. Basic Information Specialist classification: otolaryngology examination classification: neuroelectrophysiology Applicable gender: whether men and women apply fasting: not fasting Tips: Do not tamper with the inspection to prevent the machine from being in poor contact and the correct potential is not displayed. Normal value SP does not increase, SP/AP ratio <0.4. Clinical significance Abnormal result 1. The diagnosis of Meniere's disease "-SP" is increased, so that the ratio of -SP/AP is greater than the upper limit of the normal range (≥0.4 or =0.45), the SP-AP complex is broadened, and the polarity of SP and AP is opposite. AP is negative and SP is positive. 2. Sensory hearing loss SP is not easy to identify, and the CM threshold is obviously improved or the maximum stimulation intensity is still not revealed. The disappearance of CM is an important feature of sensorineural hearing loss. 3. Neurological hearing loss AP can disappear, but CM is normal or roughly normal. 4. The advantage of auditory neuropathy-SP (SP/AP>0.4), -SP is multi-peak, SP-AP complex waveform is widened, AP amplitude is reduced or disappeared. (SP is the sum potential and AP is the auditory nerve complex potential) Abnormal results: patients with hearing impairment. Precautions Taboo before inspection: Wash your ears. Taboo when checking: 1. Must be carried out in the laboratory to choose a quiet environment. 2. Do not tamper during inspection to prevent poor contact of the machine and show no correct potential. Inspection process Under the stimulation of sound, the sound waves are transmitted from the vestibular window to the cochlea, causing the movement of the basement membrane, causing the cilia of the outer hair cells to be bent due to the scissors movement, forming a local current change at the top of the hair cells, and converting the mechanical energy into electrical energy. Three electrical responses were generated: the ear socket micropotential CM), and the potential (SP) and the auditory nerve integrated action potential (AP), which were stimulated and analyzed. Not suitable for the crowd Unsuitable for people: patients with hearing loss between 1000 and 4000 Hz of 40-50 dB are not suitable for cochlear electrograms. Adverse reactions and risks Nothing.