Clinical Investigation and Development of Multifocal Posterior Chamber Lens

ABSTRACT

Since March 1990, we had tried to develop domestic-made multjfocal posterior chamber lens (PCL) in cooperation with Universal Optic Co. And then on April. 1992, we developed 3-zone multifocal intraocular lens after evaluation of lens design and its refractive power. Form June to July in 1992, we implanted this multifocal intraocular lens in 8 cataract patients(8 eyes) after obtaining informed consent and evaluated its clinical efficacy. Scanning electron microscopy revealed well manufactured, fine optic and haptic portion and smooth treatment of 3-zone optic surface for near vision. At 6 months after operation, 4 patients achieved naked distance visual acuity of 0.8 to 1.2 and 4 patients showed visual acuity of 0.5 to 0.7. Naked near vision was improved to J1(1 patient), J2(1 patient) and J3(2 patients), 4 patients obtained raked near vision below J3, 6 patients showed final refractive state within +/-1.0D and 2 patients noted hyperopic shift(+1.25 ~ +2.0D). On slit lamp examination, all PCLs were well centered in-the-bag after mydriasis and other complications related to PCL insertion were not occurred. The most common subjective symptom was halo at night(6 patients). Three patients also complained a ring shadow around the objects. Contrast sensitivity was decreased especially at night in all patients. From these results, this domestic-made multifocal PCL was effective to restore near and distance vision in cataract patients but side effects such as halo, ring shadow were resulted from the its unique 3-zone optic portion. Therefore, further investigation and study will be necessory to develop ideal type of multifocal PCL.