Tags

Type your tag names separated by a space and hit enter

Prevention of otitis media with effusion by repeated air inflation in a monkey model.
Arch Otolaryngol Head Neck Surg. 2000 May; 126(5):609-14.AO

Abstract

OBJECTIVES

To test the following hypotheses that (1) middle ear (ME) air inflation prevents the development of otitis media with effusion in a monkey model of functional eustachian tube obstruction, and (2) ME inflation treatment of otitis media with effusion can cause artifactual clinical improvements due to fluid displacement from the tympanum to the adjacent airspaces.

DESIGN

Randomized controlled trial.

SUBJECTS

Twelve cynomolgus monkeys.

INTERVENTIONS

Eustachian tube dysfunction was induced by botulinum paralysis of the right tensor veli palatini muscle in all monkeys. Before and on study days 9, 15, and 21 after paralysis, the presence or absence, and distribution of ME effusion were documented using magnetic resonance imaging (MRI). Right and left ears were examined twice daily for 21 days using tympanometry, and right ME air inflation (n = 6 ears) or sham inflation (n = 6 ears) was done immediately after those examinations if the ME pressure was -100 mm H2O or less. On 10 of the scheduled MRI evaluations, the MRI was repeated immediately after an inflation to document the possible redistribution of fluid within the ME caused by the maneuver.

RESULTS

Middle ear pressure remained within normal limits for the follow-up period in 11 of the 12 nonparalyzed left ears, in none of the 6 sham-inflated right ears, and in 3 of the 6 air-inflated right ears. Three air-inflated right ears developed flat tympanograms (ie, days 14 through 16). Magnetic resonance imaging documented inflammation and fluid in 1 of the 11 nonparalyzed left ears and in all sham-inflated right ears. Lesser degrees of inflammation and effusion based on MRI evaluations were noted for the 3 air-inflated right ears that retained near-ambient pressures when compared with the right 3 ears that developed a flat tympanogram. The MRI measure of effusion quantity within the tympanum was decreased acutely after inflation, but was simultaneously increased in the adjacent airspaces of the temporal bone.

CONCLUSIONS

Repeated air inflation prevented the development of otitis media with effusion in 50% of the ears with functional eustachian tube obstruction. Postinflation MRI documented the displacement of fluid by inflation from the tympanum to the mastoid and petrous air cells. Using standard clinical evaluations such as tympanometry and otoscopy, this fluid redistribution can cause a false diagnosis of improvement.

Authors+Show Affiliations

Department of Pediatric Otolaryngology, Children's Hospital of Pittsburgh, PA 15213, USA.No affiliation info availableNo affiliation info available

Pub Type(s)

Journal Article
Research Support, U.S. Gov't, P.H.S.

Language

eng

PubMed ID

10807328

Citation

Alper, C M., et al. "Prevention of Otitis Media With Effusion By Repeated Air Inflation in a Monkey Model." Archives of Otolaryngology--head & Neck Surgery, vol. 126, no. 5, 2000, pp. 609-14.
Alper CM, Swarts JD, Doyle WJ. Prevention of otitis media with effusion by repeated air inflation in a monkey model. Arch Otolaryngol Head Neck Surg. 2000;126(5):609-14.
Alper, C. M., Swarts, J. D., & Doyle, W. J. (2000). Prevention of otitis media with effusion by repeated air inflation in a monkey model. Archives of Otolaryngology--head & Neck Surgery, 126(5), 609-14.
Alper CM, Swarts JD, Doyle WJ. Prevention of Otitis Media With Effusion By Repeated Air Inflation in a Monkey Model. Arch Otolaryngol Head Neck Surg. 2000;126(5):609-14. PubMed PMID: 10807328.
* Article titles in AMA citation format should be in sentence-case
TY - JOUR T1 - Prevention of otitis media with effusion by repeated air inflation in a monkey model. AU - Alper,C M, AU - Swarts,J D, AU - Doyle,W J, PY - 2000/5/12/pubmed PY - 2000/5/20/medline PY - 2000/5/12/entrez SP - 609 EP - 14 JF - Archives of otolaryngology--head & neck surgery JO - Arch Otolaryngol Head Neck Surg VL - 126 IS - 5 N2 - OBJECTIVES: To test the following hypotheses that (1) middle ear (ME) air inflation prevents the development of otitis media with effusion in a monkey model of functional eustachian tube obstruction, and (2) ME inflation treatment of otitis media with effusion can cause artifactual clinical improvements due to fluid displacement from the tympanum to the adjacent airspaces. DESIGN: Randomized controlled trial. SUBJECTS: Twelve cynomolgus monkeys. INTERVENTIONS: Eustachian tube dysfunction was induced by botulinum paralysis of the right tensor veli palatini muscle in all monkeys. Before and on study days 9, 15, and 21 after paralysis, the presence or absence, and distribution of ME effusion were documented using magnetic resonance imaging (MRI). Right and left ears were examined twice daily for 21 days using tympanometry, and right ME air inflation (n = 6 ears) or sham inflation (n = 6 ears) was done immediately after those examinations if the ME pressure was -100 mm H2O or less. On 10 of the scheduled MRI evaluations, the MRI was repeated immediately after an inflation to document the possible redistribution of fluid within the ME caused by the maneuver. RESULTS: Middle ear pressure remained within normal limits for the follow-up period in 11 of the 12 nonparalyzed left ears, in none of the 6 sham-inflated right ears, and in 3 of the 6 air-inflated right ears. Three air-inflated right ears developed flat tympanograms (ie, days 14 through 16). Magnetic resonance imaging documented inflammation and fluid in 1 of the 11 nonparalyzed left ears and in all sham-inflated right ears. Lesser degrees of inflammation and effusion based on MRI evaluations were noted for the 3 air-inflated right ears that retained near-ambient pressures when compared with the right 3 ears that developed a flat tympanogram. The MRI measure of effusion quantity within the tympanum was decreased acutely after inflation, but was simultaneously increased in the adjacent airspaces of the temporal bone. CONCLUSIONS: Repeated air inflation prevented the development of otitis media with effusion in 50% of the ears with functional eustachian tube obstruction. Postinflation MRI documented the displacement of fluid by inflation from the tympanum to the mastoid and petrous air cells. Using standard clinical evaluations such as tympanometry and otoscopy, this fluid redistribution can cause a false diagnosis of improvement. SN - 0886-4470 UR - https://www.unboundmedicine.com/medline/citation/10807328/Prevention_of_otitis_media_with_effusion_by_repeated_air_inflation_in_a_monkey_model_ L2 - https://jamanetwork.com/journals/jamaotolaryngology/fullarticle/vol/126/pg/609 DB - PRIME DP - Unbound Medicine ER -