Related Experiment Video
Updated: Jun 3, 2026
Auditory Brainstem Response and Outer Hair Cell Whole-cell Patch Clamp Recording in Postnatal Rats
Published on: May 24, 2018
Cochlear function in 1-year-old term infants born with hypoxia-ischaemia or low Apgar scores
Ze D Jiang1, Zeng Zang, Andrew R Wilkinson
1Children's Hospital, Fudan University, Shanghai, China. zedong.jiang@paediatrics.ox.ac.uk
Insights
Infants born with perinatal hypoxia-ischaemia (HI) or low Apgar scores show reduced distortion product otoacoustic emissions (DPOAEs) at one year, indicating potential cochlear dysfunction. Postnatal changes in DPOAEs were minimal in these high-risk infants.
Area of Science:
- Neonatal care
- Auditory neuroscience
- Pediatric audiology
Background:
- Perinatal hypoxia-ischaemia (HI) and low Apgar scores are critical indicators of neonatal distress.
- Auditory function, particularly cochlear health, can be affected by adverse perinatal events.
- Distortion product otoacoustic emissions (DPOAEs) are a non-invasive measure of outer hair cell function in the cochlea.
Purpose of the Study:
- To investigate the impact of perinatal hypoxia-ischaemia (HI) or low Apgar scores on distortion product otoacoustic emissions (DPOAEs) in infants at one year of age.
- To assess for any postnatal changes in DPOAEs in these infants.
- To correlate perinatal factors with cochlear function at one year.
Main Methods:
- Eighty-eight term infants with perinatal HI or low Apgar scores were evaluated at one year.
- Distortion product otoacoustic emissions (DPOAEs) were measured at ten frequencies (0.5 kHz to 10 kHz) in ears with normal tympanometry.
- Infants were assessed for DPOAE pass rates across different frequencies.
Main Results:
- DPOAE pass rates were significantly decreased at frequencies from 1 kHz to 10 kHz, especially at 1 kHz and 2 kHz, in infants with HI and low Apgar scores.
- Overall DPOAE pass rates were lower in both study groups compared to normative data.
- Slight increases in DPOAE pass rates were observed at one year in infants with HI compared to earlier assessments, while minimal changes were noted in infants with low Apgar scores.
Conclusions:
- Decreased DPOAE pass rates at one year, particularly at 1 kHz and 2 kHz, suggest impaired cochlear function in infants with perinatal HI and low Apgar scores.
- These findings highlight a potential risk for hearing acuity deficits in this population.
- Further research is warranted to fully ascertain the hearing acuity and long-term auditory outcomes.
Aim:
To examine the influence of perinatal hypoxia-ischaemia (HI) or low Apgar scores on distortion product otoacoustic emissions (DPOAEs) in infants at 1 year and detect any postnatal changes.
Methods:
Eighty-eight term infants born with perinatal HI or low Apgar scores alone were recruited at 1 year of age. The ears with type A tympanogram (normal) were studied with DPOAEs at 10 frequencies between 0.5 kHz and 10 kHz.
Results:
DPOAE pass rates were decreased at all frequencies 1-10 kHz, particularly 1 and 2 kHz in both infants born with HI and those with low Apgar scores (χ(2) = 3.80-15.09, P < 0.05-0.01). Overall pass rates in the two groups were also decreased (X(2) = 10.78 and 12.12, P < 0.01 and 0.01). No marked differences were found between infants born with HI and those with low Apgar score. Compared with those recorded at 1 and 6 months, DPOAE pass rates at 1 year were increased slightly in infants born with HI, but showed no marked changes in those born with low Apgar scores.
Conclusions:
DPOAE pass rates, mainly at 1 and 2 kHz, were decreased at 1 year in infants born with perinatal HI and low Apgar scores, suggesting a relative poor cochlear function. Further studies are needed to ascertain the hearing acuity.
