Περίληψη:
Objective: To investigate whether transient-evoked and
distortion-product (DP) otoacoustic emissions (OAEs) are more sensitive
than pure-tone audiometry (PTA) in revealing gentamicin-induced
ototoxicity in children with cystic fibrosis (CF).
Design: Prospective case-control study.
Setting: Tertiary referral audiologic center in conjunction with an
academic pediatric CF unit.
Participants: The study group consisted of a consecutive sample of 12
audiologically normal children with CF and a history of gentamicin
exposure (CF-gentamicin group). The control groups consisted of 8
age-matched children with CF and 11 age-matched healthy volunteers. No
member of the control groups had a history of aminoglycoside exposure.
Intervention: Members of the CF-gentamicin study group received 4 mg/kg
of gentamicin per day for a mean of 14.2 days (range, 11-29 days).
Outcome Measures: The PTA thresholds (250-8000 Hz) were the criterion
standard. Transient-evoked OAEs’ reproducibility at 5 frequency bands
(800, 1600, 2400, 3200, and 4000 Hz) and total emission level were
measured, as were DP-audiogram (DP-gram) amplitude (1001-6299 Hz),
input-output function dynamic range, and detection thresholds at 4004,
6006, and 7996 Hz. Baseline measurements were compared between groups
examining the effect of CF and previous gentamicin exposure (2-way
analysis of variance). For the CF-gentamicin group, baseline
measurements were compared with those at the end of the last gentamicin
treatment (paired t test).
Results: The PTA findings were normal for all groups at baseline and
remained normal in the CF-gentamicin group after treatment. The
CF-gentamicin group had significantly lower transient-evoked OAEs total
emission level, DP-gram amplitude at 5042 Hz, and input-output dynamic
ranges with higher detection thresholds in all frequencies compared with
both control groups, which was attributed completely to previous
gentamicin exposure (P<.05). After treatment, further decreases in total
emission levels, DP-gram amplitudes (>3000 Hz), and dynamic ranges were
noted, with increased detection thresholds (P<.05).
Conclusions: Otoacoustic emissions measurement (especially of DP OAEs)
proved more sensitive than PTA in revealing minor cochlear dysfunction
after gentamicin exposure. They should be used for monitoring patients
receiving ototoxic factors such as aminoglycosidcs.
Συγγραφείς:
Stavroulaki, P
Vossinakis, IC
Dinopoulou, D
Doudounakis, S
and Adamopoulos, G
Apostolopoulos, N
