A man goes to the doctor, concerned about his wife’s hearing. The doctor says, “Stand behind her and say something and tell me how close you are when she hears you.” The man goes home, sees his wife in the kitchen, cutting vegetables. About 15 feet away he says, “Hi, what’s for dinner?” Nothing. He gets halfway to her and repeats the same question. Nothing. Very concerned, he gets right behind her and asks again “What’s for dinner?” She turns around and says “For the third time, Veg Pulao!”
Though it is a joke, sometimes we do not know that our hearing ability have gone down, until and unless when we are being told. That takes me to the subject of hearing disability. This blog is about” Otosclerosis”. Gradual hearing loss is the most frequent symptom of otosclerosis. They cannot hear low-pitched sounds or whispers. Other symptoms of the disorder can include dizziness, balance problems, or a sensation of ringing, roaring, buzzing, or hissing in the ears or head.
Otosclerosis
Otosclerosis is derived from the Greek words for “hard” [scler-o] and “ear” [oto]. It describes a condition of abnormal growth in the tiny bones of the middle ear, which leads to a fixation of the stapes bone. The stapes bone must move freely for the ear to work properly and hear well.
Otosclerosis is a hereditary condition in the middle ear affecting 1 in 200 person resulting in conductive hearing loss. Otosclerosis was first described by Antonio Maria Valsalva, an Italian anatomist. A skilled anatomist, he conducted many autopsies on deceased patients during the 17th century, during the times where there were lacking chemical tests and knowledge of disease transmission mechanisms. Most cases of otosclerosis are asymptomatic and only diagnosed as incidental findings in temporal bone autopsies. Women are more likely to develop otosclerosis than men.
Ear functions
In a normal ear, sound vibrations are funneled by the outer ear into the ear canal where they hit the eardrum. These vibrations cause movement of the eardrum that transfers to the three small bones of the middle ear, the malleus, incus, and stapes. When the stapes bone moves, it sets the inner ear fluids in motion, which, in turn, start the process to stimulate the auditory [hearing] nerve. The hearing nerve then carries sound energy to the brain, resulting in hearing of sound. When any part of this process is compromised, hearing is impaired. The hallmark symptom of otosclerosis, slowly progressing hearing loss, can begin anytime between the ages of 15 and 45, but it usually starts in the early 20’s.
Causes
Genes can be read like words in a book. If there is a spelling change in the gene, or word, it does not work properly. Sameway a specific change in a gene, which changes the instructions for the function of hearing. Those who inherit this genetic change are likely to develop some degree of otosclerosis, which is a change in the size and hardness of bone in the ear.
We typically inherit two copies of each gene, one copy from our mother, and one copy from our father. The trait is expressed if one inherited copy of the gene is not working properly. A child in this family has a 50% chance of inheriting a non-working copy of the gene and a 50% chance of inheriting the working copy.
Other cause may be due to Measles infection in childhood.
Diagnosis is by ENT examination.
Treatment
If the bony growth is present mainly in the middle ear, surgery can be very effective in restoring most hearing. If surgery is not possible, hearing aids can be beneficial. Severe hearing loss may be treated through cochlear implantation.
Prevention and future
Considered a complex disease, little is known about its pathogenesis. Researchers in Canadian University have identified the genes that are responsible for this abnormal growth of the ear bone. This discovery will definitely provide new insights into genes and pathways involved in Otosclerosis and renewed hope for options for otosclerosis are now within striking distance.
Gregor Mendel, father of modern genetics should get a rebirth in this world to further unravel the mysteries in genetics and that would help humankind to a greater extent.
Note-The images given for representation in this blog are taken from Google / Unsplash Images. Many thanks for Google & Unsplash.