Repeated Atmospheric Pressure Alteration Effect on the Cochlea in Rats: Experimental Animal Study.

Area of Science:

• Otolaryngology
• Aerospace Medicine
• Occupational Health

Background:

• Repeated exposure to atmospheric pressure alterations is common for flight crew.
• The effects of these pressure changes on inner ear structures are not fully understood.
• Understanding these effects can inform occupational health strategies for aviation personnel.

Purpose of the Study:

• To evaluate the impact of repeated pressure alterations on rat cochlear structures.
• To indirectly assess the inner ear status of individuals exposed to frequent pressure changes, such as flight crew.

Main Methods:

• 12 Wistar albino rats were divided into control and study groups.
• The study group experienced repeated pressure changes in a pressure cabin for 12 weeks.
• Auditory brainstem response (ABR) testing and scanning electron microscopy (SEM) of cochleas were performed.

Main Results:

• The study group exhibited hearing decreases at various frequencies (2, 4, 8, and 32 kHz).
• SEM revealed irregularities, collapse, adhesions in the basal cochlea, and partial stereocilia loss in the study group.
• Control group cochleas showed normal outer hair cells (OHC) and stereocilia.

Conclusions:

• Repeated atmospheric pressure alterations can cause inner ear damage and hearing loss.
• Flight crew and frequent flyers may be at risk for occupationally-induced inner ear damage.
• This risk warrants consideration as a significant occupational health concern.