Around the world, 700 million people suffer from hearing loss. That’s a lot of people – 10% of the global population. But are they all suffering from the same type of hearing loss?
Of course, hearing loss happens gradually and progressively over time, meaning there’s a spectrum of different hearing losses, from mild to profound. There are also two different broad types of hearing loss, sensorineural and conductive.
What are they and why does it matter to you? Read on to find out.
Sensorineural hearing loss
Also known as SNHL, sensorineural hearing loss is the most common form of hearing loss, accounting for around 90% of cases. Sensorineural hearing loss can be managed, but not cured.
Sensorineural hearing loss is an umbrella term for a group of inner ear and neurological symptoms and conditions. Split the word ‘sensorineural’ in two and you get an idea of what they are: the ‘sensory’ part includes damage to the cochlea hair cells that absorb sound vibration, while ‘neural’ refers to problems with the vestibulocochlear nerve, which transmits sound and balance information to the brain.
The symptoms of SNHL include: Difficulty picking out speech against noisy backgrounds. Difficulty understanding speech on the telephone. Certain sounds are too loud. Trouble hearing certain speech sounds, especially fricatives and sibilant fricatives (including ‘f’, ‘th’, ‘s’, and ‘ch’ sounds). Difficulty detecting the source or direction of a sound.
What are the specific conditions that fall into the sensorineural category?
Presbycusis – also known as age-related hearing loss, this the most common cause of hearing loss. The hair cells within the inner naturally degrade over time, typically from the age of 40 onwards; 40% of over-50s experience some hearing loss. By 80, many people face significant hearing loss.
Noise-induced hearing loss (NIHL) – the hair cells inside your ears are delicate, and long-term exposure to loud noises can damage them irrevocably.
Head injuries or viral infections (such as mumps, measles or rubella) – can damage either the vestibulocochlear nerve or the cochlea, causing permanent or temporary hearing loss.
Diseases such as meningitis and encephalitis – causing damage to the cochlea.
Conductive hearing loss
Conductive hearing loss covers a range of conditions that block or partially obstruct sound waves from entering the middle ear, eardrum or outer ear. In many cases, conductive hearing loss can be treated, although some conditions can be permanent.
The symptoms can vary from mild hearing loss to pain in the ear:
Sounds seem faint or muffled. Low, bassy frequencies are harder to discern. Young children may have difficulty understanding speech or responding to prompts. Some conductive hearing loss conditions, like otitis media, can be painful.
Conductive hearing loss includes a range of conditions, including:
Excessive cerumen – too much earwax in your ear. An object trapped in the ear. A perforated eardrum. Exostoses – a bone growth inside the ear canal. Otosclerosis – calcification of the middle ear bones. Otitis externa – infection or irritation of the outer ear. Otitis media – inflammation of the middle ear, sometimes accompanied by ‘glue ear’. Stenosis or atresia – a narrowing or blockage of the ear canal. Swelling or dysfunction of the eustachian tube (which maintains the balance of pressure in the ear).