How is the hearing degree of deafness graded?

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It is generally believed that the average hearing threshold of language frequencies (0.5, 1, 2, 4KHz) is above 26dB, that is, hearing impairment. Those with hearing loss within 70dB are called hard of hearing, and those with hearing loss above 70dB are deaf. Clinically, it is commonly referred to as deafness. .


How is the hearing degree of deafness graded?

Classification of deafness:
According to the WHO 1980 deafness classification standard, the average speech frequency pure tone hearing threshold is divided into 5 levels.
Mild deafness: There is no difficulty in listening to general conversations at close range. The audiometer checks that the pure tone and speech hearing thresholds are 26 to 40dB.
Moderate deafness: It is difficult to hear words at close range, the hearing threshold is 41-55dB
Moderate and severe deafness: It is difficult to hear loud speech at close range, the hearing threshold is 56-70dB.
Severe deafness: You can only hear when you shout loudly in the ear, the hearing threshold is 71-91dB.
Total deafness: unable to hear loud shouting in the ear, pure tone hearing threshold exceeds 91dB.

Generally speaking, if the hearing loss in both ears reaches above the hearing threshold of 40dB (above moderate in the old version of the hearing classification), it will cause difficulties in communication in daily life. After clinical evaluation, fitting may be recommended Hearing Aids.


Types of deafness:
1. Conductive deafness: Deafness is caused by lesions in the outer and middle ears that impede the sound conduction process. . Common causes of deafness include external auditory canal obstruction, foreign bodies, inflammation, congenital ear canal atresia, acute and chronic suppurative otitis media, acute and chronic non-suppurative otitis media, congenital malformations, tumors, bullous myringitis, early otosclerosis, etc.
2. Sensorineural deafness, neurosensory deafness: refers to the inability of cochlear spiral organ disease to transmit soundThe wave becomes nerve excitement or the nerves and their central pathways are blocked and cannot transmit nerve excitement; or the cerebral cortex center lesions cannot distinguish language, collectively referred to as sensorineural deafness. Clinically, deafness is caused by ear complications of various acute and chronic infectious diseases, drug or chemical substance poisoning, labyrinthitis, membrane labyrinth hydrops, temporal bone fracture, acoustic neuroma, craniocerebral trauma, cerebrovascular accident, cerebrovascular sclerosis or spasm, etc. and presbycusis can be summarized in sensorineural deafness.
3. Mixed deafness: There are lesions in both the sound-transmitting and sound-sensing mechanisms. Such as long-term chronic suppurative otitis media, advanced otosclerosis, blast deafness, etc.


Deafness will bring serious troubles to our lives and may also cause psychological problems to patients, so we must do a good job in deafness prevention Preventive work, don’t let deafness happen and let us live in a silent time. Deafness refers to the lesions of the auditory nerves and centers at all levels in the auditory system’s sound transmission, sensory and auditory conduction pathways, causing hearing dysfunction to varying degrees. Hearing loss is collectively called deafness. Depending on the degree of hearing loss, it is also called hard of hearing, hearing impairment, hearing loss, hearing loss, etc.