配戴角膜塑型镜片后角膜上皮铁线的临床观察

Clinical observation of iron deposition in the corneal epithelium after wearing Orthokeratology lenses

目的观察青少年近视眼患者配戴角膜塑型镜片（Orthokeratology，Ortho-K）后角膜形态的改变情况。方法选择配戴Ortho-K镜1年以上近视眼患者85例，165眼；观察时间为24-33月，在裂隙灯下仔细检查配戴Ortho-K镜患者的角膜（有时需采用后照明法），可观察到角膜上皮铁线。结果在配戴Ortho-K镜的165眼中，有140眼可观察到角膜上皮铁线，占观察眼数的84．8％，其中视力达到1．0的有115眼（占82．14％）；无上皮铁线的患者中，视力达到1．0的有15眼（占57．41％）。配戴Ortho-K镜后，患者角膜铁线形状为水平下半环形，多呈月牙状，其环形直径约为4-5mm，宽约为0．6-1mm。铁线位于角膜上皮细胞层。其颜色为棕色或淡棕色。结论近视眼患者配戴Ortho-K镜1年后，大部分患者有特异性角膜上皮铁线形成。该铁线位置恰与Ortho-K镜反转弧（RC弧）对应，位于瞳孔视区之外，未见其影响视力。而且有铁线形成的患者多是镜片居中、镜片稳定性好、视力佳的病例。

Objective To observe changes in the cornea of adolescent myopia patients after wearing Orthokeratology （Ortho-K） lenses. Mathods One hundred sixty-five eyes of 85 cases of patients who wore Ortho-K lenses for more than one year were enrolled in the study. Of these 85 cases, 24 were males and 61 were females, with ages ranging from 11 to 19 years. The mean age was （15.5 ± 2.6）years. Their uncorrected visual acuity （UCVA） ranged from 0.05 to 0.5, with a mean uncorrected visual acuity of 0.20 ± 0.10 ; refractive error ranged from - 1.50 D to - 6.00 D, with a mean refractive error of （ - 4.02± 1.78）D; the follow-up period for visits was 24 to 33 months, with a mean observation wriod of （28.25 ± 3.74）months. After wearing Ortho-K lenses, the patient＇ corneas were carefully examined with a slit lamp and sometimes with retro illumination as well so iron deposition in the corneal epithelium could be specifically identified. Results Iron deposition in the corneal epithelium was found in 140 of 165 eyes after wearing Ortho-K lense, accounting for 84.8% of the patients＇ eyes. Of those with iron deposition in the corneal epithelium, 115 eyes （82.14%） had a 1.0 visual acuity; of those without iron deposition, 15 eyes （57.41%） had a visual acuity of 1.0. The iron depesition was located in a semicircular pattern in the lower half of the cornea. The diameter of the circle was 4 to 5 millimeters and the width was 0.6 to 1 millimeter. Iron deposition within the basal corneal epithelium was brown or light-brown in color. Conclusion Iron deposition was found in meat of the adolescent myopia patients who had worn Ortho-K lenses for over one year. The position of the iron deposition coincided exactly with the FC of the Ortho-K lens （RC）, located outside of the optical area of the pupil, and vision was not affected. Also, in most of the cases where the lens wes centrally located, stabilization and vision were good when iron deposition was found.