[Advantages of Krats's laser pointer associated with the Weiss coordimeter in the study of cyclofusion]

The cyclofusional abilities of some patients can lead to an underevaluation of their deviation. This study proposes an original and specific analysis of cyclofusion and discusses its practical applications.

We followed 19 consecutive patients, 14-69 years of age (mean, 43.7 years), presenting slight excyclotorsion (measured by the striated Maddox glasses), never exceeding 4 degrees and often at 0 degrees (63%) even in down gaze. A positive Bielschowsky head tilt test was assessed in all cases but was moderate in 75%. Objective excyclotorsion was observed in 12 out of the 14 documented cases. Diplopia was present (essentially in lateral gaze) in 68%, despite a small vertical deviation in primary position and in lateral gaze. Krats's linear pointer was associated with the Weiss coordimeter (fusional and nonfusional forms) to study the topographic measurements of the torsion in relation to fusion. All cases presented an unilateral form of symptomatology.

In all cases but one, our method was more specific than the Maddox glasses in demonstrating the presence and the variation of the excyclotorsion. We completed this analysis by comparing the two coordimetric forms for a successful prescription of vertical prisms in four cases. Torsional surgery was proposed to two patients and successfully conducted in 13 other cases.

This methodology provided improved specificity of the topographic measurement of the cyclodeviation, for a better comprehension and treatment of this underevaluated symptomatology.