Measurement of subjective and objective cyclodeviation in oblique eye muscle disorders

Surgically induced changes of eye torsion often show a subjective over-effect which resolves later on. Hence the authors initiated a prospective study with the purpose of analyzing motoric and sensoric elements in postoperative rotational changes by comparing subjective and objective cycloduction. Fundus cyclometry, a new method for measurement of objective cycloduction, is introduced. An image of the posterior pole is obtained by an infrared Scanning Laser Ophthalmoscope without pupil dilatation and is transferred to a computer system by which nature and amount of objective cycloduction is calculated. Four patients who underwent surgery for oblique eye muscle disorders are presented. Objective torsional changes were slightly higher than subjective changes. Postoperative reduction of torsional changes was noted subjectively and objectively in all cases. For statistical reasons further investigations on a great number of patients are needed to interpret the postoperative changes in terms of motoric and sensoric cyclofusion.