Recovery (healing) phase of acute secretory otitis media, showing the presence of bubbles. Minor tympanosclerosis, the presence of white, chalky plaques on the eardrum, the tympanic membrane, is also apparent. Otitis media occurs as a sequel to bacterial or viral infections in the upper respiratory tract, which spreads up via the eustachian tube. Fluid & pus accumulate due to a blocked, inflamed tube; the pressure increase may perforate the eardrum & damage the tiny bones within. The resulting degree of deafness ranges from slight transient to total.