Eustachian Tube (ET) is a canal that connects the middle ear to the nasopharynx. ET performs gas transfer and pressure equalisation; clearance of mucus from the middle ear; and prevention of sound or fluid reflux from the nasopharynx. ETF is the test to identify opening and closing of Eustachian Tube.
ETF can be performed whether the tympanic membrane is intact or perforated. ETF test is a series of three tympanograms on Resting middle ear pressure, Valsalva & Toynbee. ETF test is interpreted based on the shift between the peaks. Shift of 15 – 20 decapascals (daPa) between tympanograms suggests Normal Eustachian Tube Function.