Ventilation tubes are inserted to cure recurrent / frequent bouts of acute otitis media / chronic otitis media with effusion. Grommet insertion is particularly useful to treat patients with chronic mucoid otitis media.
Delay in insertion of ventilation tubes in these patients can cause chronic otitis media / chronic mastoiditis in these patients. Ventilation tubes measuring about 1.1 mm are known to last for atleast a year before being extruded. In patients with prolonged eustachean tube dysfunction these tubes help in prevention of atelectasis. If tubes measuring 1.5 mm are used they could stay in situ for prolonged duration thereby allowing adequate time for the middle ear healing process.
Studies have demonstrated that proper placement of these ventilation tubes can be helpful in delaying the process of extrusion.
Ventilation tubes should not be inserted in the postero superior quadrant because of the impending risk of incus dislocation. Similary placement in the postero inferior quadrant is also discouraged because of the risk of damage to round window. In this location there is also the added risk of damaging a high jugular bulb which could be an anatomical variant.
Classically the antero inferior quadrant is perferred because of the proximity to eustachean tube. Insertion in this area has one important flip side, i.e. Early extrusion of the ventilation tube.
Insertion of ventilation tune i.e. In the antero superior quadrant adjacent ot the handle of malleus and half way between the umbo and short process of malleus will serve the purpose of ventilation of middle ear adequately. Ventilation tubes placed in this quadrant have been known to stay in place for more than a year serving the important ventilatory function of middle ear cavity.
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