electrical audiometry

It is a method of recording potential changes induced by the auditory system due to sound stimulation using modern electronic techniques. Due to the development of modern auditory electrophysiology and electronic computer technology, the induced weak electrical response can be clearly displayed to objectively evaluate the functional state of the auditory system. It is suitable for the detection of hearing threshold, the functional paralysis and the identification of organic sputum, the identification of cochlear and posterior sinus lesions, the diagnosis of acoustic neuroma and some central lesions in infants and young adults. Basic Information Specialist classification: otolaryngology examination classification: neuroelectrophysiology Applicable gender: whether men and women apply fasting: not fasting Tips: Keep a normal mindset. Normal value normal. Clinical significance Due to the development of modern auditory electrophysiology and electronic computer technology, the induced weak electrical response can be clearly displayed to objectively evaluate the functional state of the auditory system. It is suitable for the detection of hearing threshold, the functional paralysis and the identification of organic sputum, the identification of cochlear and posterior sinus lesions, the diagnosis of acoustic neuroma and some central lesions in infants and young adults. Precautions In addition to the same requirements for pure-tone audiometry, the electrical response audiometry requires the inspection of the electrical shielding of the environment to minimize the interference of environmental electrical noise on the potential recording. Inspection process (1) Cochlear electrogram: The characteristics of the cochlear action potential (AP) response threshold close to the hearing threshold can be used to objectively evaluate the hearing threshold of difficult partners, and combined with other audiological examination methods to identify the deafness lesions (conduction, cochlear or cochlear) . (2) Auditory brainstem response (ABR): It is a short latency potential and is usually tested with short sound. Can be combined with other audiological examinations to identify the nature of hearing loss; most commonly used to check for post-cochlear lesions: such as prolonged latency of each wave, prolonged inter-wavelength interval, significant inter-earth latency or inter-wave phase difference, and waveform differentiation Poorness suggests the possibility of post-cochlear lesions. ABR main differential diagnosis: 1 transmission deafness: V wave response threshold is increased but the threshold latency is in the normal range. The sonic latency-intensity function curve shifts to the right. 2 Meniere's disease: The deafness of the deafness is increased by the threshold of the V wave, but the acoustic period is less than 20 dB above the threshold, and the latency is shortened and reaches the normal value; 3 acoustic neuroma: I-V interval is prolonged or V The wave disappears, but if the patient's I wave is not clearly affirmed, the false positive rate is very high. At this time, combined with the cochlear electrogram comprehensive analysis, the diagnostic accuracy can be improved. The IV interval difference between the two ears is greater than 0.4ms, or the IV interval is greater than 4.6ms (should consider age and gender factors), suggesting post-cochlear lesions; 4 Diagnosing brain stem lesions: multiple sclerosis, brain stem vascular disease and brain stem Tumors and the like can also cause the amplitude of the evoked potential to decrease, the latency to be prolonged, or the waveform to disappear. It should be identified in combination with the medical history and related examinations. Functional paralysis and false sputum: The hearing threshold can be objectively assessed, but it should be noted that short latency potentials and short-sound examinations tend to underestimate residual hearing in the low-frequency domain. (3) Mid-latency potential (MLR) is mainly used to measure lesions in the auditory pathway above the brainstem, such as multiple sclerosis including the midbrain to the primary auditory cortex (demyelinating, vascular, inflammation). Sex and tumor); for infants and other difficult partners can be used to identify residual hearing and visitor observation, supplemented by low-frequency regional hearing that ABR is not easily assessed. It is recommended to provide stimulation at a rate of 40 times/s for clinical use, producing a 40 Hz auditory response-related potential (40 Hz AERP), which is closer to the subjective hearing threshold than the conventional MLR, and the response is easily identifiable. Not suitable for the crowd Generally there are no people who are not suitable. Adverse reactions and risks Generally no adverse reactions.