A new device to assess static ocular torsion.

Inclinicalsettings,staticoculartorsionisassessedbytakingafundusphotographandmeasuringtheanglebetweena horizontallineandthelineconnectingthefoveatotheheadoftheopticnerve(centro-cecalaxisrotation;CCAR).We developed and tested a system specifically aimed at CCAR measurements, based on low-cost commercial hardware, and that implements an adaptive research algorithm that selects and presents bright dots on a monitor to outline thebordersoftheblindspot,locateitscenter,andmeasureCCAR.Weexamined10healthysubjectswhounderwent four CCAR measurements to evaluate the reliability of the system and compared our results with those of fundus photographic examination. Our data showed an excyclophoria, with mean ocular torsion of 6.4◦ in the right and 6.7◦ in the left eye. These values are in keeping with those in the literature. Moreover, the values of the intraclass correlation coefficients suggest excellent reliability of the technique.