A new device for performing the Jackson Cross Cylinder test for astigmatism is compared against the traditional flip cylinder, or "J.C.C. ", technique. The device, a component of the 1-TRAC 8000 Refractor from R.H. Burton Company, uses an electronically controlled, microprocessor based, rotating cross cylinder. The instrument also features a digital display that reads out axis to single degree accuracy. As claimed by the manufacturer, this combination should a! low for easier, faster determination of cylinder power and axis, with greater accuracy. This study compares subjective refraction results determined with a conventional flip cross-cylinder, as mounted on a Reichert Ultramatic Rx Master Phoroptor, against the subjective refraction determined with the rotating cross-cylinder found on the Burton ITRAC Refractor. Refractions were performed on 40 volunteer subjects ranging in age from 21 to 56 and excluded individuals exhibiting any ocular pathology or binocular difficulties. The cylinder power findings from the paired refractions showed a relatively poor correlation (R = .846) when compared to the very high correlations found between the spherical rated their overall reaction to the new instrument as positive.
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