Binocular fixation pattern
R. F. Zipf
The binocular fixation pattern (BFP) is a convenient clinical test that may
be used to diagnose strabismic amblyopia in children who are too young to
cooperate with conventional testing of visual acuity. A retrospective
analysis of amblyopic and nonamblyopic patients with esotropia and
exotropia demonstrates the effectiveness of the BFP in detecting strabismic
amblyopia in children under 4 years of age. Amblyopic patients with either
esotropia or exotropia reliably demonstrate strong grades of preference.
Nonamblyopic patients with esotropia or exotropia usually demonstrate weak
grades of fixation preference, with the important exception that most
patients with small angles of esotropia have strong fixation preference
even in the absence of amblyopia.
