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Published on: February 18, 2012
Bell's phenomenon in newborns and premature babies
1Department of Ophthalmology, Beilinson Medical Center, Petah Tikva, Israel.
Insights
Bell
Area of Science:
- Neonatal neuro-ophthalmology
- Developmental pediatrics
Background:
- Bell's phenomenon (BP) is a protective reflex.
- Understanding its development in neonates is crucial for assessing neuro-ophthalmic maturation.
Purpose of the Study:
- To evaluate the development and course of Bell's phenomenon (BP).
- To compare BP development in premature versus full-term neonates.
Main Methods:
- Studied 27 preterm and 42 full-term infants.
- Assessed BP reflex grading longitudinally.
- Recorded birth weight, gestational age, and head circumference.
Main Results:
- No preterm infants showed BP in the first week; 29.6% had a reflex by 8 weeks.
- 35.7% of full-term neonates had a mature reflex by 3 days, and 97.3% by 16 weeks.
- BP correlated with sex, birth weight, and gestational age in preterm infants.
Conclusions:
- Bell's phenomenon exhibits a longitudinal developmental course.
- BP serves as a key clinical marker for neuro-ophthalmic maturation in neonates.
Aims:
To evaluate the development and course of Bell's phenomenon (BP) in premature and normal neonates.
Methods:
Twenty seven preterm infants and 42 healthy full term infants were studied. Mean birth weight, gestational age, and head circumference were recorded. BP was graded from no response to full response. The premature group was examined in the first week of life, and then at 4 and 8 weeks after birth. The full term group was initially examined at the age of 3 days until a full response was observed.
Results:
No preterm infants exhibited BP during the first week of life, while 8/28 (29.6%) exhibited a weak to full reflex at 8 weeks of age. In the full term group 15/42 neonates (35.7%) demonstrated a mature reflex at age of 3 days and 36/37 (97.3%) at age 16 weeks. A significant correlation was observed between BP, sex, and birth weight, as well as gestational age in the premature group. No such correlation was found in the full term infants.
Conclusion:
BP has a longitudinal course. It is an important clinical marker for evaluation and follow up of neuro-ophthalmic maturation in neonates.
