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Horizontal and vertical angle kappa
1Department of Ophthalmology and Vision Sciences, The Hospital for Sick Children and the University of Toronto, Canada. veit.sturm@usz.ch
Background:
The aim of this study is to report the geometric range of angle kappa formation in patients with and without strabismus.
Patients And Methods:
This is a retrospective study of three patients with angle kappa in different planes. Routine eye examinations, including visual acuity, slit-lamp examination, and ophthalmoscopy, were performed. A thorough orthoptic examination revealed a notable difference between the prism and alternate-cover test and the Hirschberg measurements.
Results:
The first patient exhibited a bilateral vertical angle kappa into opposite directions due to retinochoroidal scars. Two other patients presented with horizontal angle kappa deviations. In one patient a true accommodative esotropia was exaggerated by a right negative angle kappa. The other patient had a pseudoexotropia due to bilateral positive angle kappa. Macular ectopia was noted in all cases.
Conclusions:
The patients herein reported demonstrate a marked variability of angle kappa occurrence in the horizontal and vertical plane. The angle kappa can exaggerate or conceal the size of the true heterotropia.
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