Hearing loss refers to impaired auditory function resulting from pathological changes in the auditory system's sound transmission, sensory perception, auditory nerve pathways, or central nervous system centers, leading to varying degrees of hearing impairment. Generally, an average speech frequency hearing threshold exceeding 26 dB is classified as hearing loss or hearing impairment.Depending on severity, it is also termed deafness, hearing impairment, hearing loss, or diminished hearing.
The causes of deafness are complex, involving both congenital and acquired factors. Among these, suppurative otitis media is the primary cause of conductive deafness. In recent years, secretory otitis media has become the leading cause of hearing loss in children.
Based on the location and nature of the lesion, deafness can be classified into four types: conductive deafness, sensorineural deafness, mixed deafness, and central deafness.A thorough medical history should be obtained; the external auditory canal and tympanic membrane should be examined; tuning fork testing and pure-tone audiometry should be performed to determine the nature and degree of hearing loss. For children and uncooperative adults, subjective behavioral audiometry and objective audiometry tests such as impedance audiometry, auditory brainstem response (ABR) testing, and electrocochleography (ECoG) may also be conducted. Diagnosis is then made in conjunction with clinical presentation.
Traditional Chinese medicine classifies deafness into the following patterns: Liver-Kidney Yin Deficiency, Heart-Spleen Deficiency, Qi and Blood Deficiency, Phlegm-Dampness Obstructing the Middle, and Liver-Gallbladder Damp-Heat.
Deafness arises from numerous causes, including genetics, infections, improper medication use, immune disorders, physiological degeneration, and poisoning by certain chemicals.Early detection, diagnosis, and treatment are crucial for hearing loss. For conductive and mixed hearing loss, identifying the root cause and implementing comprehensive treatment to improve the middle ear environment and sound transmission function can maximize hearing recovery.