Medical Q&As

Grommets - what are they?

My 5-year-old grandnephew is due to have his adenoids removed and grommets inserted to help his hearing. Can you let me have information on what grommets are and how they will affect him?

A grommet is a small dumbbell-shaped plastic device with a narrow opening passing through it. It is mainly used in the treatment of a condition known as glue ear. Glue ear is a very common problem in young children and can cause deafness. The glue or fluid accumulates in the middle ear and clogs up the hearing mechanism. It also physically blocks the efficient transmission of the sound wave as it passes from the outer ear, through the middle ear and on to the inner ear. The glue accumulates due to blockage of the Eustachian tube, which connects the back of the throat and the middle ear. This tube aerates the middle ear and allows a little puff of air to travel up to the middle ear every time we chew, swallow or yawn. In the case of glue ear this aeration no longer takes place due to the blockage of the Eustachian tube and this in turn results in increasing pressure in the middle ear due to the increasing levels of fluid or glue. It is customary to remove the adenoids when grommets are being inserted. An incision is then made in the eardrum and a small suction tube is passed through the eardrum and the fluid in the middle ear is withdrawn by gentle suction. The grommet is then inserted through the small incision and is left in the eardrum with one end of the “dumbbell” inside the middle ear and the other end sitting in the outer ear. I t might help to visualise it if you think of an old-fashioned collar stud sitting in the child’s eardrum. The grommet is then left in that position and helps to aerate the middle ear. If the grommet were not inserted the incision in the eardrum would simply heal after a few days and the fluid would re-accumulate within a very short space of time. The grommets are eventually extruded from the eardrum after some months. It is permissible for children to swim and bathe while using grommets because the hole in the grommet is very small and would not permit water to enter the middle ear. However, it is not advisable for a child to dive or put its head under water because the increased pressure underwater could drive water through the hole in the grommet. Air travel is not a problem for a child with grommets because the hole in the device allows equalisation of air pressures on either side of the eardrum.