CORNEAL TOPOGRAPHY USING THE HOLLADAY DIAGNOSTIC SUMMARY

Purpose: To describe new software developments in videokeratography an d illustrate their application in patients with corneal disease or pat ients who have had keratorefractive surgery. Methods: The Holladay Dia gnostic Summary provides 4 maps and 15 corneal parameters for the clin ician. The maps include 2 refractive power maps on standard and auto s cales, a profile difference map for determining the corneal shape rela tive to normal asphericity, and a distortion map to display the optica l quality of the cornea. The 15 corneal parameters provide quantitativ e information about the cornea for a 3.0 mm pupil; e.g., effective ref ractive power, regular astigmatism, asphericity, and predicted corneal acuity. The maps and parameters are used to analyze a calibration bal l and five clinical examples. Results: Patients with diseases such as keratoconus or patients who have had keratorefractive surgery have cha racteristic changes in the 4 maps and the 15 corneal parameters. Concl usion: When true refractive power maps, a profile difference map, a di stortion map, and 15 corneal parameters are analyzed, characteristic c hanges are found that can help clinicians recognize and monitor cornea l disease and refractive surgery and correlate these changes with pati ents' visual symptoms.