‘Astigmatism management during eye surgery is a complex issue. For many decades it has been known that marks must be placed upon the eye with the patient in an upright position for references once the patient is in the supine, surgical orientation since cyclotorsion can be significant. It can often be slight rotation (5 degrees or less) but quite often 10 degrees can occur. Mastel has personally been in surgery where cyclorotation or torsion have occurred at a range of 20 degrees. Our new Zero Parallax Visual Axis Glasses solve the patient/surgeon common light pathway along the mutual visual axes of both the patient and surgeon.
Alignment simply means ‘along a common line’; this must occur to place accurate and reproducible astigmatism premarks for toric lenses or AK. We accomplish this with a patented solution whereby the surgeon has a blinking red light placed over their dominant eye. With clever optical engineering, we allow the patient to look directly at the surgeon’s eye and fixation line while the surgeon objectively visualizes around the visual axis by the corneal light reflexes of the unique lighting system to ensure true alignment while eliminating guessing games. The fact that the device eliminates parallax issues while maintaining stereopsis for the surgeon yet eclipsing optically the light reflexes in the non-dominant eye of the surgeon avoids the risk of cross-fixation of the Purkinjie-Sanson images.’