The Subjective Angle as a Basis for the Surgery of the Anatomical Deviation

Summary

Esotropia is dissociated into its two components: the anatomical deviation (minimal deviation in principle) and the dynamic deviation (functional esotropia). The value of the Subjective Angle (Striated glasses test) is compared with the value of the minimal objective deviation (and not as it is usually done with a global deviation) before and after surgery. The surgical suppression of the spasm allows an interesting control of the diagnosis of anomalous correspondence.

When an angle of anomaly is found its average value is always 6 diopters in small and in large deviation. In many cases, the surgical suppression of the spasm causes an immediate disappearance of the angle of anomaly even if orthophoria is not established. In these cases of ‘false’ A.R.C., the angle of anomaly is thus part of the spasm embodied in the measure of the minimal deviation. The ‘angle of anomaly’ in true A.R.C. is still 6 diopters (before and after surgery). It could be the same part of the spasm (unable to carry on a proper localization) totally fixed.

Practically, the value of the subjective deviation always has to be taken into account in our surgery since it is the closest to the anatomical deviation. In adults a surgery of relocation based on the value of the subjective angle, plus a Fadenoperation for the value of the angle of anomaly, gives in many cases an orthophoria with binocularity, suggesting those closed relations existing between the angle of anomaly and the spasm.