Measurement of objective cyclodeviation using Cyclocheck® software

Purpose
To present a new, free web-based software (www.cyclocheck.com) designed for the measurement of objective cyclodeviation and to assess its usefulness in diagnosing congenital and acquired superior oblique palsy.

Material and methods
15 patients with unilateral superior oblique palsy were enrolled in the study group. Patients were classified according to aetiology as to the group of congenital or acquired palsy. Subjective cyclodeviation was assessed by Harms tangent screen. Objective torsion was measured by means of fundus photography with determination of the disc-foveal angle using Cyclocheck® application.

Results
Excyclotropia was discovered in 6 patients with congenital palsy (33%) and 9 individuals with acquired palsy using the Harms tangent screen (89%). Fundus photography revealed excyclotropia in all patients from the study group. The difference between the mean disc-foveal angle in congenital and acquired group was non-significant (p = .316). The objective excyclotropia to vertical deviation and subjective excyclotropia to objective excyclotropia ratios were significantly larger in the acquired group, p = .029 and p = .006 respectively.

Conclusions
Measurement of objective ocular torsion by means of Cyclocheck® application is a valuable diagnostic tool in detecting cyclodeviation in patients with superior oblique palsy, especially of congenital aetiology. Presence of excyclotropia on the eye fundus without subjective cyclodeviation measured by the Harms tangent screen indicates congenital aetiology. Results of both tests should be considered taking into account the ocular dominance.