Tympanostomy tubes: a review of recent studies

Ear, Nose & Throat Journal, Sept, 2004 by Thomas Deitmer

I would like to review the results of some interesting recent studies that have been performed on children who have received tympanostomy tubes.

Timing of tube placement

Should tympanostomy tubes be placed immediately in infants with otitis media with effusion (OME) to prevent speech, language, cognitive, and psychosocial impairments? To investigate the timing of tube placement, Paradise et al conducted a study of 6,350 healthy infants, aged 2 to 61 days. (1) Of this group, 429 children had developed OME before they had reached the age of 3 years. These patients were randomized to undergo tympanostomy tube placement either immediately or as long as 9 months later if OME persisted. At study's end, data were available on 235 patients--169 in the early-treatment group and 66 in the late-treatment group. The authors found no significant differences between the two groups with respect to speech, language, cognitive, and psychosocial development. They concluded that prompt insertion of tubes does not measurably improve outcomes in infants.

The lesson we can take from this is that watchful waiting or conservative treatment for a period of some months is a reasonable option. We should not be in a hurry to place tubes in these patients unless relapsing acute otitis media makes surgical steps mandatory.

Adjuvant adenoidectomy or adenotonsillectomy

Coyte et al conducted a retrospective chart review of 37,316 patients (age: [less than or equal to] 19 yr) who had undergone tube placement as their initial surgical treatment for OME. (2) They found that patients who had undergone concomitant adenoidectomy with or without tonsillectomy had a lower incidence of tube reinsertion and hospital readmission for OME-related causes than did patients who underwent tube placement alone. In fact, the adenotonsillectomy group fared even better than the adenoidectomy group.

Although the reasons for the mechanisms of benefit associated with adenoidectomy and adenotonsillectomy are not proven, we can conclude that the grommet alone does not cure the disease.

Hearing aids

Ahmmed et al conducted a mail survey of consultant otolaryngologists in the United Kingdom with respect to their use of grommet reinsertion or hearing aid placement in children with persistent OME following tube extrusion. (3) Among the 319 otolaryngologists who responded, 158 (49.5%) said they either never or rarely recommended a hearing aid, 146 (45.8%) said they sometimes did, and 15 (4.7%) said they routinely did.

The authors concluded that a randomized, controlled comparison of hearing aids and tube reinsertion in these cases would be helpful. For now, I believe that hearing aids should be used only in patients with recurrent OME who have severe inflammatory problems with their ventilation tubes. In these cases, I would try mastoidectomy to cure a draining ear before recommending a hearing aid.

Tube coatings

In an in vitro study, Kinnari et al tested the ability of tubes coated with human serum albumin to prevent occlusion by fibronectin, which they used as a representative exudate. (4) The tubes were made of various materials. The authors found that, depending on the tube material used, the albumin-coated tubes were 59 to 85% more effective in preventing fibronectin binding than were uncoated tubes.

Bacterial biofilms have been implicated in the development of persistent posttympanostomy tube otorrhea and irreversible tube contamination. Berry et al compared the incidence of biofilm development on three different types of fluoroplastic tube--a phosphorylcholine-coated tube, a silver-oxide-impregnated tube, and an uncoated tube--after they had been incubated with Staphylococcus aureus or Pseudomonas aeruginosa. (5) No biofilms were found on the phosphorylcholine-coated tubes, whereas both bacteria appeared on the silver-oxide-impregnated tubes, and P aeruginosa was isolated on the untreated tubes.

Plugging

Westine et al performed two studies on tube blockage. In the first, they endeavored to identify the composition of tube plugs. (6) They examined the luminal contents of 105 plugged tubes by liquid chromatography. They found that the composition of the plugs was more similar to mucoid effusion than to blood or cerumen.

In the second study, they attempted to determine the most effective solvents for dissolving dried mucoid effusions. (7) They obtained 260 plugged plastic tubes and tested 12 solvents, including ototopical antibiotics and water. They found that the most effective solvents were diluted vinegar and hyaluronidase solutions. Of the two, they preferred the vinegar because of its documented safety in the ear.

Sequelae

Finally, Kay et al performed a meta-analysis of studies on the incidence of tympanostomy tube sequelae. (8) Their findings:

Otorrhea: transient postoperative otorrhea, 16%; delayed otorrhea, 26%; recurrent otorrhea, 7.4%; and chronic otorrhea, 3.8%

Indwelling tubes: obstruction, 7%; granulation tissue, 5%; extrusion, 3.9%; and medial displacement, 0.5%

Postextrusion: tympanosclerosis, 32%; focal atrophy, 25%; perforation, 16.6% with long-term tubes and 2.2% with short-term tubes; retraction pocket, 3.1%; and cholesteatoma, 0.7%