The ears can be cleared by various methods, some of which pose a distinct risk of
barotrauma including perforation of the eardrum: •
Yawning which helps to open the eustachian tubes; •
Swallowing which helps to open the eustachian tubes; • The "
Frenzel maneuver": Using the rear part of the tongue and throat muscles, close the nostrils, and close the back of the throat as if straining to lift a weight. Then make the sound of the letter "K." This pushes the back of the tongue upward, compressing air into the openings of the eustachian tubes. • "
Politzerization": a medical procedure that involves inflating the middle ear by blowing air up the nose during the act of swallowing; • The "Toynbee maneuver": pinching the nose and swallowing. Swallowing pulls open the eustachian tubes while the movement of the tongue, with the nose closed, compresses air which passes through the tubes to the middle ear. • The "
Valsalva maneuver": pinching the nose and closing the mouth and trying to breathe out through the nose. If the hand cannot reach the nose, it is possible to learn to pinch the nose shut by the action of two small face muscles called
compressor naris. This is the first technique normally taught, but needs to be performed gently to lessen side-effects. • The "Lowry technique", a combination of Valsalva and Toynbee: pinching the nose to close the nostrils, and blow and swallow at the same time. The nose can be closed without using a hand, using the
compressor naris muscles; it can be described as "wrinkling the nose as if there was a bad smell". A hand cannot access the nose if using a
full facemask. Therefore, many eyes-and-nose
diving masks have two small pockets in their underside, or, like
goggles, have the soft edge extended downwards over the nose, to let two fingers reach the nose and pinch it. • The "Edmonds technique": while tensing the soft palate (the soft tissue at the back of the roof of the mouth) and throat muscles and pushing the jaw forward and down, do a Valsalva maneuver. • The "BTV method" ('''', voluntary opening of the tubes): Tense the muscles of the soft palate and the throat while pushing the jaw forward and down as if starting to yawn. This may require some
training. No single method is considered safest or most successful in equalization of the middle ear pressure. Using alternative techniques may improve the success individually when a technique fails. ==Precautions==