Tympanostomy tube, also known as a grommet, myringotomy tube, ventilation tube, or pressure equalizing tube, is a small tube inserted into the eardrum via a surgical procedure called myringotomy to keep the middle ear aerated for a prolonged period of time, typically to prevent accumulation of fluid in the middle ear.

The tube itself is made in a variety of designs, most often shaped like a grommet for short-term use, or with long flanges and sometimes resembling a T-shape for long-term use. Materials used to manufacture the tubes are often made from fluoroplastic or silicone, which have largely replaced the use of metal tubes made from stainless steel, titanium, or gold. Tympanostomy tubes are typically placed in one or both eardrums to help children suffering from recurrent acute otitis media (ear infection) or persistent otitis media with effusion (sometimes called "glue ear").

Tympanostomy tubes work by improving drainage, allowing air to circulate in the middle ear, and offering a direct route for antibiotics to enter the middle ear. Tube placement has been shown to increase hearing in children with persistent otitis media with effusion and may lead to fewer ear infections for children with frequent ear infections.

  • Chronic otitis media with persistent effusion for six months (one ear) or three months (both ears).

While tympanostomy tubes are commonly used in children, they are seldom used in adults. Options for use in adults include:

  • Persistent eustachian tube dysfunction. Saline washouts and antibiotic drops at the time of surgery are effective measures to reduce rates of otorrhea, which is why antibiotic ear drops are not routinely prescribed.
  • Blockage of the tympanostomy tube (7-10%)

Surgical intervention may be required in cases of persistent perforation or retained tympanostomy tubes. Persistent perforations are corrected via tympanoplasty with an 80-90% success rate.

Procedure

Myringotomy with insertion of tympanostomy tubes is performed by an ENT doctor (otolaryngologist) and is one of the most common pediatric surgical procedures, accounting for more than 20% of all ambulatory pediatric surgeries in 2006.

During the procedure, a small incision is made to the eardrum using either a myringotomy knife or a CO<sub>2</sub> laser. The middle ear is then usually washed out thoroughly with saline before the tympanostomy tubes are placed. Antibiotic drops are commonly used during surgery once tubes are placed but are not routinely prescribed for use following surgery unless recommended by a doctor for individual reasons. It is approximated that a child would need to wear ear plugs for 2.8 years to prevent one additional ear infection. For nearly two hundred years, scientists would study and debate the potential benefits of myringotomy before German scientists Martell Frank and Gustav Lincke had the first documented use of tympanostomy tubes in 1845. These scientists used an approximately 6mm long gold tube in an attempt to prevent the eardrum from closing after myringotomy.

From 1845 to 1875, seven different types of tympanostomy tubes were manufactured and made of materials including rubber, silver, aluminum, and gold. These tubes were not widely used or accepted due to complications including falling into the middle ear, falling out of the ear, and the tubes getting plugged.