Objective: To search for the characteristics of MFS in corneal morphology and thickness.
Methods: Twenty-four patients (48 eyes) with MFS and 24 healthy age- and gender-matched volunteers (48 eyes) were recruited in this clinical prospective, and comparative series study. Firstly, biomicroscopic examination and Type-A ultrasonometry was conducted to search for ectopia lentis and axis length. Secondly, the corneal morphologic parameter [including the height of anterior and posterior surface, the centre corneal curvature, the mean astigmatism in the 3.0-mm central zone (Mean A), the mean simulated astigmatism (Sim A), the mean keratometry in the 3.0-mm central zone (Mean K), the mean simulated keratometry (Sim K), the 3.0-mm zone irregularity (3.0ZI), the 5.0-mm zone irregularity (5.0ZI), corneal thickness index (CTI)] and thickness (at the central location and at eight midperipheral locations) were obtained by the the autorefractometer and the Orbscan II Z corneal topography. Last, the statistics method including Crosstabs, One-way ANOVA, student-t test and discriminant analysis were applied and the correlations were established.
Results: There is no statistically significance between MFS group and control group in ages (38 ± 7) and (37 ± 8) years, gender (8/16) and (9/15), and axis length (23.12 ± 1.06) mm and (24.26 ± 2.96) mm (age χ(2) = 0.091, P = 0.763;gender t = 0.324, axis length t = 1.976, P > 0.05). Flat cornea ratio (66.7% and 12.5%) and topography of the oval (25.0% and 16.7%), irregular bow-shaped (41.7% and 37.5%) and irregular-shaped (12.5% and 8.3%) were increased significantly in patients with MFS. The corneal topography (MFS/control) showed that there are statistically significance in the thinnest thickness of cornea (489.8 ± 42.9)µm and (544.8 ± 25.7)µm, Mean K (40.60 ± 1.30) D and (42.80 ± 1.40) D, Sim K (40.50 ± 1.30) D and (42.80 ± 1.20) D, Sim A (1.08 ± 0.86)D and (0.91 ± 0.46) D, CTI 1.57 ± 0.24 and 1.21 ± 0.14, 3.0ZI (1.76 ± 0.96) D and (1.54 ± 0.82) D, and 5.0ZI (1.91 ± 1.26) D and (0.92 ± 0.68) D (thinnest thickness t = 6.996, Mean K t = 2.554, Sim K t = 3.326, Sim A t = 2.324, CTI t = 3.116, 3.0ZI t = 2.686, 5.0ZI t = 3.768, P < 0.05), while no statistically significance in the Mean A between the MFS (1.11 ± 0.89) D and control group (0.99 ± 0.49) D (Mean A t = 1.898, P = 0.08); except for temple inferior, the significant decrease of pachymetry (including the center and the seven midperipheral locations) appeared in the MFS group compared with the control group.
Conclusion: The characteristic of MFS in corneal topography is that corneal axial refractive power descends and corneal thickness decreases.