Effect of 1.8-mm steep-axis clear corneal incision on the posterior corneal astigmatism in candidates for toric IOL implantation

Table 2 Preoperative and postoperative corneal astigmatism

variance		Mean ± SD	95%CI	minimum	maximum
Anterior corneal	Astigmatism (D)	1.58 ± 0.61	1.42,1.73	0.70	3.70
	K₁ (D)	43.36 ± 1.67	42.92,43.79	39.20	46.60
	K₂, (D)	44.96 ± 1.64	44.54,45.38	41.40	48.60
	Astigmatism (D)	1.26 ± 0.68*	1.08,1.44	0.30	3.30
	K₁, (D)	43.32 ± 1.74	42.87,43.77	39.20	46.90
	K₂, (D)	44.61 ± 1.68	44.18,45.05	40.50	48.00
Posterior corneal	Astigmatism (D)	0.28 ± 0.22	0.22,0.33	0.00	0.80
	K₁ (D)	−6.28 ± 0.25	−6.35, −6.22	−6.80	−5.80
	K₂, (D)	−6.55 ± 0.27	−6.62, − 6.48	−7.20	−6.00
	Astigmatism (D)	0.41 ± 0.26*	0.35,0.48	0.00	1.10
	K₁, (D)	−6.33 ± 0.28*	−6.41, − 6.26	−5.80	−6.90
	K₂, (D)	−6.75 ± 0.37*	−6.85, − 6.66	−6.10	−7.70

The shaded part represents preoperative corneal astigmatism; and the non-shaded parts represent postoperative corneal astigmatism. Asterisk* represents a significant difference (P < 0 .05) compared with the preoperative astigmatism. SD standard deviation, CI confidence interval, D diopters, K₁ keratometric value at the flattest corneal meridian, K₂ keratometric value at the steepest corneal meridian

ISSN: 1471-2415