Scuba diving is fun but it can damage the ears. I worked for a month as a dive doctor on an island in the Caribbean for a research and training team. I found that 50% of the divers coming to my clinic had ear problems. Infection was the commonest by far. Perforated eardrum is the other common problem. The high pressure of the water and the prolonged immersion cause the issues. When the pressure changes during ascent and descent the ear drum may rupture. This happens if the pressure on either side of the drum isn't equalised by the Eustachian Tube.
The Eustachian Tube is a narrow canal connecting the space in the middle ear with the nasal cavity. This communicates with the outside world via the nose. This means it is always the same pressure as the ambient surroundings. The problem arises when the diver has Eustachian Tube Dysfunction. This can be caused by a cold or other problem stopping air flowing down the tube.
Local inflammation causes swelling and narrowing of the tubes. Mucus also builds up which causes blockage. When the pressure changes it does not equalise across the drum and a gradient builds up. This can reach the point where the drum can tear and a perforation occurs. This was a big deal for the divers as they had taken time out for trip and it was important to them. I found people were often upset about having to stay out of the water until the hole healed. This could take six weeks or more.
Some holes never heal and need to be repaired by a surgeon. A tiny paper patch is taped over the hole.
Ear infections are common amongst keen divers who dive in warm waters like the Carribean. They are often frequent and severe. I was working in the Caribbean where the waters are warm. The divers spent 10 hours or more in the sea every day resulting in severe infection. I remember divers visiting me with pus running down their faces from their ears. These waters are high in bacteria. This is because they multiply much more quickly at high temperatures.
When severe the infection may need antibiotics by mouth as well as drops. Washing the ears with clean water or surgical alcohol can prevent the problem.
In shallow waters antibacterial ear plugs like ZenPlugs are useful for preventing ear infections. Unfortunately they are not recommended for use at depth. This is because they create a pocket of air. The pressure cannot be equalized with the outside world. This makes them unsuitable for preventing ear infections in this situation.
Divers with severe infection need to stay out of the water. They also need to use their antibiotics until the problem settles.
Dr Toby Bateson