Placing small ventilation tubes through the eardrum (tympanic membrane) is not an unusual practice to help interrupt the cycle of repetitive middle ear infections. The tubes allow the middle ear to dry out until the draining function of the eustachian tubes returns to normal. Swelling and inflammation from the infection process in the eustachian tubes prevents fluid from draining properly. The insertion of the tubes through a small incision (myringotomy) in the tympanic membrane usually corrects this situation.
The tubes are not meant to be permanent implants and usually fall out on their own or are removed by the physician. The small incision usually heals shortly after the tubes are removed. In rare cases a small hole may remain after the tubes are left in for a long period. This situation can be tested for and is best addressed by your son's physician. It is unlikely that the tubes are still in place after six years, but you should have your son's ears checked by his physician.
Diving is not recommended while the tubes are in site, as they will allow water to enter the middle ear, risking vertigo and infection. However, after removal or extrusion, adequate time for healing must be allowed, at least six weeks, and middle ear and eustachian tube function must be confirmed as normal before diving is considered.
A bigger problem may be scarring to the eustachian tubes from the chronic ear infections. This can make ear clearing difficult for the young diver. There is no surgical procedure to date that can correct a eustachian tube that is partially occluded. Loss of eustachian tube function can be big trouble for divers. Children and adults alike need immediate attention for symptoms of middle ear infection and barotrauma. Symptoms may include but are not limited to pain, ringing or roaring in the ears, a sensation of partial loss, decreased or muffled hearing and drainage from the ear canal.