Hearing loss is of two types:
- Congenital – This is when the child is born with a hearing impairment which is largely due to inherited genetic factors or problems in the prenatal environment or at the time of birth.
- Acquired – This is when the child develops hearing loss in either one ear or both ears after birth.
Causes of Congenital Hearing Loss
- Genetics – Heredity usually plays a big role in the case of congenital hearing loss. Children of parents who have hearing loss (even if it is one parent with hearing loss) are more likely to be genetically vulnerable. Obviously, the probability is more if both parents are carrying dominant genes for hearing loss or even if grandparents on one side suffer from hearing loss. Parents who are able to hear properly can also be carrying recessive genes which can get passed onto the children.
- Infections – During pregnancy, if the woman is suffering from German Measles, toxoplasmosis, cytomegalovirus, herpes virus or syphilis, the intrauterine infections can result in hearing loss for the infant.
- Birth injuries – Sometimes, there can be complications in the birth process such as lack of oxygen or a requirement for blood transfusion or head trauma that can cause injuries which result in hearing loss.
Causes of Acquired Hearing Loss
- Otitis Media – This is the most common cause for hearing loss for kids. Otitis media is caused by the accumulation of fluid behind the eardrum of the infant or child. This can be due to an allergy or even a respiratory infection, both of which are very common among small children. The fluid accumulates and causes earache and swelling. It prevents the bones of the middle ear from vibrating, thereby making sound transmission difficult. This hence results in difficulty in hearing for the child. Most of these infections are usually detected early and treated. But if they are left untreated and the fluid remains in the ear, the infection may recur or worsen. In extreme cases, the eardrum can rupture leading to permanent hearing loss.
- Eardrum perforation – Tiny rips or tears in the eardrum are called perforations. They are mostly minor and can heal by themselves. But larger tears can cause risk of infection as the eardrum acts as a barrier to keep pollutants out of the middle ear. A blow to the head can cause a bigger tear, thereby leading to hearing loss.
- Environmental noise – Frequent exposure to loud noise from the surroundings such as horns, trains, loud music or traffic can significantly lower hearing abilities in children.
Symptoms of Hearing Loss
Parents are usually the first to notice signs of hearing loss in children. It is important for parents to monitor the hearing of their children especially between birth till four years of age as this is a crucial formative period in milestone development. Hearing loss can occur at any time however and the beginning signs may not be immediately obvious. The following signs can alert parents to the probability of hearing loss in the child:
- Difficulty in learning to speak – Children learn to speak by listening to speech and language around them. If this milestone is delayed as compared to other children or the child is making frequent mistakes in speech or in picking up language, a doctor must be consulted to find out if it is just a delayed milestone or symptomatic of hearing loss.
- Responses may be slow to come, delayed or incorrect. The child may seem confused about who is addressing them or may not respond when called.
- Responses may be soft in sound or even inaudible.
- The child may be facing difficulties in school with academics or even disciplinary problems. The teachers may alert the parents about certain behavior such as missing roll call or not being able to respond when the teacher calls them. This is mostly seen in acquired hearing loss as the child grows older.
- The child may frequently attempt to sit closer to the TV or radio. They may increase the volume up to a level that is louder than what they were previously accustomed to.
- They do not get startled by sudden, loud noises such as a thunder clap or a door slamming. This happens because the auditory receptors in the ears are not able to pick up this information.
- They cannot localize sound which means they may have difficulties locating the source of the sound.
- They complain frequently about headaches, earaches and ear pain.
- The child may frequently ask “What?” as an attempt to get a repetition of what was said.
- The child may prefer their good ear by moving it forward when someone talks.
In most cases, treatment may not be required as the condition may heal by itself. In the case of infections or perforations that are more severe, antibiotics may be needed. If the perforation does not heal by itself, the doctor can perform a minor surgery called tympanoplasty to restore hearing.
Cochlear Implant Surgery can be carried out by implanting an electric device that stimulates the auditory nerve with electric signals. This allows the sound information to reach the brain and sound can be interpreted here, thereby allowing the individual to hear. Children as young as a year in age can opt for this implant if they suffer from profound hearing loss or display little progress in auditory development.
In this surgery, an incision is made in the cochlea and the electrode is inserted and secured. Though largely successful, individuals have different responses to the perception of sound post the surgery. The younger the child is when the implant is inserted, the better it is for the child to develop acoustically. Surgery options in India are affordable and accessible. The entire process of consultation, assessment, diagnosis, treatment and rehabilitation may take between 3-6 weeks. You can find cost-effective centers for cochlear implant surgery in India here.