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Bell's phenomenon during screening examination for retinopathy of prematurity
Ji Eun Lee1, Jun Mo Park, Hee Young Choi
1Department of Ophthalmology, Medical Research Institute, Pusan National University School of Medicine, Busan, Korea.
Insights
Bell
Area of Science:
- Ophthalmology
- Neonatology
- Pediatric Neurology
Background:
- Bell's phenomenon (BP) is infrequently observed in premature infants.
- Examination stress may influence BP expression during retinopathy of prematurity (ROP) screening.
Purpose of the Study:
- To evaluate the frequency and influencing factors of Bell's phenomenon during ROP examinations.
- To assess the relationship between BP expression and gestational age in premature infants undergoing ROP screening.
Main Methods:
- 102 eyes of 51 premature infants were studied.
- BP was assessed after speculum insertion, indirect ophthalmoscope illumination, and scleral depression.
- Correlation between BP and gestational age was analyzed at each examination step.
Main Results:
- BP frequency was high (77%-92%) in infants ≤32 weeks, decreasing significantly (16%-57%) in infants ≥42 weeks (p < 0.005).
- BP after scleral depression showed no significant gestational age association.
- BP frequency significantly increased with examination progression (p < 0.01).
Conclusions:
- Bell's phenomenon is frequent in premature infants during ROP examinations, even with neurological immaturity.
- Examiners should consider the high occurrence of BP, particularly in younger premature infants.
Purpose:
Bell's phenomenon (BP), which may disturb screening examinations for retinopathy of prematurity (ROP), is known to present infrequently in premature babies. Stress associated with the examinations can influence expression of BP. The authors of the present study evaluated BP during examinations for ROP.
Methods:
The present study included 102 eyes of 51 premature babies. Expression of BP was assessed at 3 steps of the examination in the following order: after insertion of a speculum, after illumination of an indirect ophthalmoscope and after scleral depression. The relationship between the expression of BP and the gestational age at the examination was analyzed in each step of the examination.
Results:
The frequency of BP after the speculum insertion and the illumination was 77% to 92% in infants 32 weeks of age or younger, and decreased significantly to 16% to 57% in infants 42 weeks of age or older (p < 0.005). BP after the scleral depression had no significant association with the gestational age. Frequency of BP increased significantly as the steps of the examination proceeded (p < 0.01).
Conclusions:
BP was frequent in premature infants during ROP examination in spite of neurological immaturity. The examiner should take BP into consideration, which frequently occurs in younger infants.
