A powerful wave striking the ear of a swimmer can also perforate the drum. Infections of the middle ear can spawn a buildup of pus. That buildup puts pressure on the drum. If the pressure is not relieved, it punctures the eardrum, and pus drains out. Eardrum perforations taking up less than 50 percent of the entire area of the drum usually heal by themselves, and often they completely heal in a matter of weeks.
Patients can supply their own grafts.
You must, regardless of the perforation's size, go on a water alert. Don't take showers. Water can pass through the perforation into the middle ear. If you can't avoid taking a shower, wear a swimming cap that covers the ears. Four years ago I had a heart attack.