Korean J Ophthalmol.  2012 Jun;26(3):189-194. 10.3341/kjo.2012.26.3.189.

Bell's Phenomenon during Screening Examination for Retinopathy of Prematurity

• Lee JE
• Park JM
• Choi HY
• Oum BS

• KMID: 1376124
• DOI: http://doi.org/10.3341/kjo.2012.26.3.189

Abstract

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.

Keyword

Bell's phenomenon; Retinopathy of prematurity

MeSH Terms

Gestational Age
Humans
Incidence
Infant, Newborn
*Infant, Premature
Korea/epidemiology
Mass Screening/adverse effects/*methods/psychology
Ophthalmoscopy/*psychology
Retinopathy of Prematurity/*diagnosis/epidemiology
Retrospective Studies
Risk Factors
Stress, Psychological/*epidemiology/etiology
Vision Screening/adverse effects/*psychology

Figure

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  Fig. 1 Grading of Bell's phenomenon: (A) grade 0, no response; (B) grade 1, minimal response, or the center of cornea is seen; (C) grade 2, full response or the center of the cornea is not seen.

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  Fig. 2 Frequency and grade of Bell's phenomenon after insertion of speculum decrease significantly according to gestational age at examination for retinopathy of prematurity of (A) right eyes (p < 0.001) and (B) left eyes (p = 0.005).

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  Fig. 3 Frequency and grade of Bell's phenomenon after illumination of indirect ophthalmoscope decrease significantly according to gestational age at examination for retinopathy of prematurity of (A) right eyes (p < 0.001) and (B) left eyes (p = 0.001).

• 

  Fig. 4 Frequency and grade of Bell's phenomenon after scleral depression do not show a difference according to gestational age at examination for retinopathy of prematurity of (A) right eyes (p = 0.080) and (B) left eyes (p = 0.075).

• 

  Fig. 5 Frequency and grade of Bell's phenomenon increase significantly according to progression of the examination in premature infants with a gestational age of 36 to 38 weeks at examination for retinopathy of prematurity (ROP) of (A) right eyes (p < 0.001) and (B) left eyes (p < 0.001). No difference was found between the right and the left eyes.

• 

  Fig. 6 Frequency and grade of Bell's phenomenon increase significantly according to progression of the examination in premature infants with a gestational age of 36 to 38 weeks at examination for retinopathy of prematurity (ROP) of (A) preceding eyes (p < 0.001) and (B) following eyes (p < 0.001). No difference was found between the preceding and the following eyes.

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