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Updated: Jun 27, 2026

Discovering Middle Ear Anatomy by Transcanal Endoscopic Ear Surgery: A Dissection Manual
Published on: January 11, 2018
Is the healthy middle ear a normally sterile site?
Brian D Westerberg1, Frederick K Kozak, Eva E Thomas
1Division of Otolaryngology, Centre for Health Evaluation and Outcome Sciences (CHEOS), St. Paul's Rotary Hearing Clinic, Providence, Vancouver, Canada. BWesterberg@providencehealth.bc.ca
Objective:
To systematically evaluate the presumption that the healthy middle ear becomes colonized with organisms via the patent eustachian tube using modern microbiologic techniques.
Study Design:
Sterile saline washings were obtained from the middle ear of patients in a prospective fashion.
Setting:
Tertiary/quaternary referral centers.
Patients:
Pediatric and adult patients undergoing cochlear implantation surgery.
Intervention(S):
Standard bacterial and viral cultures, and nucleic acid amplification techniques.
Main Outcome Measure(S):
Identification of organisms.
Results:
Specimens were obtained from 13 children and 9 adults. No organisms were identified in any of the specimens, either through standard culture or PCR testing.
Conclusion:
The presumption that the healthy middle ear is colonized by bacteria from the nasopharynx is unsubstantiated.
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