The photokeratoscope view displays the image of placido rings ... Detecting Irregular Astigmatism or Other Abnormalities. Corneal topography, especially photokeratoscope view and tangential ...

Astigmatism ... shows a "bow tie" on corneal topography. The power of each meridian is successive as the meridians travel 180 degrees. Astigmatism that does not show symmetry or otherwise conform ...

The increasing power of corneal ... astigmatism; the in-situ topography map over the contact lens should appear relatively spherical; and when residual astigmatism is present, the map should show ...

“If you have any asymmetry, which is the hallmark of any ectatic disease, you can look at the topography to find that,” he said. Corneal topography is important to assess image quality in ...

This study showed that corneal topography performed ... shift in the 17 cases that did not show a change was 7.47±5.74°. Changes in the amount of astigmatism at 30–40 min and 4–6 weeks ...