Table 3.

Evaluation of Parameters Used to Determine Progression of Ectatic Disease

Variables	Post-Operation
	Δ12-Months	Δ24-Months
	N = 18	N = 9
	N (%)	N (%)
Kmax + 1 (D)a	4 (22.2)	1 (11.1)
Astg + 1 (D)b	1 (5.6)	1 (11.1)
PachyMin (µm) - 2%c	5 (27.8)	3 (33.3)
D-index + 0.42d	8 (44.4)	2 (22.2)

Notes: ^a Increase of at least 1 D in Kmax. ^b Increase of at least 1 D in astigmatism (K2-K1). ^c Decrease of at least 2% in PachyMin. ^d Increase of at least 0.42 in D-index.

Abbreviations: µm, micrometre; Astg, astigmatism; D, dioptre; K1, flat keratometry; K2, steep keratometry; Kmax, maximum keratometry; PachyMin, minimum pachymetry.