Clinical Observation Of Phakic Posterior Chamber Intraocular Lens Implantation For High Myopia Correction

Purpose To survey the clinical efficacy,safety and stability of Phakic Posterior Chamber Intraocular lens Implantation for High Myopia and to explore the impact of Nd∶YAG laser iridotomy to vision quality.Methods A Staar implantable contact lens(ICL)was implanted in 14patients(28 eyes)with high myopia.All patients were followed for six months.Comparing the uncorrected visual acuity,best corrected visual acurity,spherical equivalent,contrast sensitivity,optical aberration and before and after the iridectomy with Nd:-YAG laser and before and after implantation of the ICL.Reasults 1.Vision: UCVA and BCVA without changing after the ridectomy ( P>0.01). At One week,1-month after the Implantation of ICL the UCVA results showed a statistically significant difference:78.6%eyes≥5.0 vs 82.1%eyes≥5.0.At 1 month,28 (100%)eyes UCVA is beter than preoperative BCVA. Six months after surgery ,each period ,the SE 100% eyes were within±1.00D. 2.Contrast sensitivity: After the ridectomy with Nd:-YAG laser Contrast sensitivity got depressed when the spatial frequencies were at 3.0 c/deg, 6.0 c/deg,12 c/deg and mode of light,night,light glare,night glare.After the implantation of ICL Contrast sensitivity values among 1-month,3-month and 6-month had no statistically significant difference (P > 0.01). At 1-month spatial frequencies at 3.0 c/deg, 6.0 c/deg,12 c/deg, mode of light,night,light glare,night glare contrast sensitivity got rised.There was statistically significant difference (P < 0.01). 3.Wavefront aberration: The Zernike functional valus(T.Total,I.Total )of the eyes after the ridectomy with Nd:-YAG laser rised zhan that of before(P < 0.01).The Zernike functional valus of T.Total and I.Total in 6mm pupil size area of the postoperative eyes at 1-months,3-months,6-months of ICL implanted were found significantly statistical lower(P < 0.01) than those of the preoperative eyes,then T.High,T.Coma,T.Trefoil,I.High,I.Coma were found higer than that of before. Among 1-months,3-months,6-months after the implantation of ICL, the Zernike functional valus had no statistically significant difference.(P>0.01)Conclusion 1.Shot-term observation shows that implanting intraocular lens in posterior chamber to correct high myopia is effective, safe and stable. 2. ICL im-plantation improves the visual function of high myopia eyes.Total aberrations co-uld be decreased by implantable contact lens implantation in high myopia eyes, high-order aberrations such as T.Coma,T.Trefoil,I.Coma are increased. The po-stoperative contrast sensitivity values were found higher zhan those of the preop-erative eyes. 3.Holes (1-1.2mm) witch was made 2 weeks before the implanta-tion of ICL by iridectomy with Nd:-YAG laser, at 1 points and 11 o 'clock posi-tion can Cause some changes in visual quality.