AIM:To investigate the clinical effect of wearing rigid gas permeable contact lens(RGPCL)to correct the irregularity of anterior corneal surface after deep anterior lamellar keratoplasty(DALK).

METHODS: A prospective case-control study. 28 patients accepted RGPCL or frame glassed after DALK surgery during 2017-07/2019-01 in the General Hospital of Northern Theater Command were selected. We divided them into 2 groups according to the principle of non-random voluntariness. 18 patients(18 eyes)accepted RGPCL while 10 patients(10 eyes)accepted frame glasses were selected. Data were collected preoperative, 3mo, 6mo and 1a later, including uncorrected distant visual acuity(UCVA), corrected distant visual acuity(CDVA)and refractive diopter. Furthermore, the Oculus Pentacam Three-dimensional Anterior eye Analyzer was used to examine the corneal morphology. We calculated corneal anterior surface smooth curvature(K1), steep curvature(K2), maximum curvature(Kmax), anterior corneal surface astigmatism, Index of Surface Variance(ISV), Index of Height Asymmetry(IHA), Index of Vertical Asymmetry(IVA)and Index of Height Decentration(IHD).

RESULTS: We found no statistically significant differences between the two groups in UCVA, SE, K2, Kmax, anterior corneal surface astigmatism, IVA and IHD(P>0.05), but we found significant differences in CDVA, K1, ISV and IHA(P<0.05). In terms of CDVA, the data at 3mo was(0.38±0.16, 45.40±3.19D, 35.48±18.46, 27.91±17.19), 6mo was(0.37±0.16, 43.73±3.39D, 30.48±16.28, 25.18±16.66)and 1a was(0.34±0.21, 43.64±3.30D, 25.97±15.23, 23.46±15.24)in the RGPCL group. The data at 3mo was(0.65±0.16, 45.82±3.52D, 49.39±15.73, 28.45±16.96), 6mo was(0.60±0.15, 45.11±3.06D, 48.18±15.13, 25.95±15.93)and 1a was(0.58±0.16, 45.61±3.30D, 46.67±15.45, 25.48±15.51)(P<0.05).

CONCLUSION: RGPCL is safe and effective to improve CDVA and correct the regularity of anterior corneal surface after DALK and has advantage over frame glasses.