| Background and PurposeSurgical treatment for refractive error has concentrated the interest of Ophthalmologist. Currently wide using of excimer laser in corneal refractive surgery has demonstrated good efficiency and prediction such as PRK and Lasik. But some complications during and post operative has not resolved well. More the refractive error is, less efficacy and prediction or more complications when comeal procedure used. Clear lens extraction faces the problem of loss of accommodation and complication such as retinal detachment.Posterior chamber phakic intraocular lens is a new technique for refractive error correction. Implantable contact lens (ICL) has the best biocompatibility which was researched clinically abroad. This series using ICL implantation to correct high myopia was to investigate the technique and technology. Through compare with Lasik group the efficacy and safety of posterior chamber intraocular lens were evaluated.Material and methodsPatient including criteriaThe patients with high myopia more than -10.0D were included. The age of patients should be ranged 1 8 to 45 years. Myopia development was less than -2.0D in recent 2 years. Patients with eye surgical history and inflammation were excluded. Systemic disorder was not selected in this series. All potential complications were mentioned during preoperative introduction. All patients were asked for agreement for procedure given. According to patients two groups were separated. Preoperative examinationPreoperative examination for all of the patients including ICL and Lasik group4included uncorrected visual acuity, best corrected visual acuity with manifest and cycloplegic refraction, slit-lamp biomicroscopy, comeal topography (EyeSys), cornea! thickness pachymatry, specular microscopy (Topcon SP 2000P), anterior chamber depth, tonometry, and dilated fundscopy. Systemic history was reviewed. Phakic Intraocular Lens selectionWe used STAAR?Implantable Contact Lens manufactured with a porcine collagen/HEMA copolymer. It is designed as single peace with plate haptic. It is a foldable lens mat may be implanted through a 3.0mm comeal incision. The central thickness of minus optic zone is 60um. The central concave/convex optic comes in sizes ranging from 4.5mm to 5.5mm in diameter, depending on the lens power.The lenth between two ends of haptic is 11 -13mm, to accommodate different eye sizes. Available lens powers are for myopic lenses, -3 to -23 diopters and for hyperopic lenses, +3 to +20 diopters. The main factors of the lens for the patient are diopters and length. Surgical TechniqueIn order to decrease the incidence of postoperative papillary block two superior iridoomiest positioned 90?apart were done at two weeks before implantation. Pupil was dilated well before surgery. Anesthesia was acived with topical lidocaine or peribulbar injection. A side paracentesis and 3.0mm temporal clear comeal incision were made with diamond knife. Sodium hyaluronate (Occucoat) was injected into anterior chamber. Then ICL was injected into anterior chamber, anterior to the iris plane. Four comers of ICL haptic were placed beneath iris with a intraocular hook. Acetylcholine was injected into anterior chamber to constrict pupil. Remaining viscoelastic was removed with gentle irrigation and aspiration with Staar Phacoemulsification system or replaced by BSS injection. All of corneal incision were no leakage. Follow-upRoutine postoperative examination were scheduled at 1 day, 1 week, 1 month, 3 months, 6 months, 1 year, 2 years. All follow-up examination included UCVA, BCVA with refraction, low-contrast vision and glare vision, slitlamp biomicroscopy, and for ICL group specular microscopy, flare of anterior chamber, position of ICL, crystalline lens clarity were particularly observed. For lasik group the particular examination included the healing of comeal flap, changes under flap, comeal topography. Analysis MethodsComparison of efficacy, safety index, low contrast and glare vision between two5groups was performe...
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