The Clinical Outcomes of Lens Exchange in Patients with Opacified Posterior Chamber Lens

PURPOSE: To evaluate the outcomes of posterior chamber lens (PCL) exchange in patients with opacified foldable PCLs. METHODS: This study consisted of 31 patients (35 eyes) who had received phacoemulsification and implantation of foldable intraocular lenses in the bag or sulcus and developed late opacification of the PCL. All patients reported a reduction of visual acuity and deterioration in vision. The PCLs were explanted and replaced with new PMMA lenses. The perioperative complications and the best corrected visual acuities (BCVAs) before and after surgery were evaluated. RESULTS: The mean visual acuities (logMAR value) before and after IOL exchange were 0.59+/-0.80 and 0.21+/-0.27, respectively. The difference was statistically significant (p=0.005, paired t-test). Intraoperative complications included posterior capsule rupture in six patients, zonular dehiscence in three patients, and both in one patient. Postoperative complications included intraocular pressure elevation in five patients and cystoid macular edema in two patients. One patient showed hypopyon at 6 days postoperatively, which lasted for 3 months, but she showed good visual acuity. CONCLUSIONS: Intraocular lens exchange was a safe and effective treatment for patients whose PCLs were opacified.

Effect of Cataract Surgery through Clear Corneal Incision in Glaucomatous Eyes with Filtering Blebs

The small-incision cataract surgery by phacoemulsification with foldable posterior chamber lens implantation have recently permitted new options for combined trabeculectomy with cataract extraction. In the present study, we performed phacoemulsification and foldable intraocular lens implantation using small clear corneal incision in 20 patients with 22 glaucomatous eyes who had previously undergone trabeculectomy and determined its effects on visual acuity, intraocular pressure, the number of medications applied, and status of the filtering blebs. The mean follow-up period was 10.1 months and the mean time interval between the two surgeries was 14.7 months. The mean best corrected visual acuity was 0.19 preoperatively and 0.60 postoperatively and the postoperative visual acuity had improved in 19 eyes(86.4%). The mean(+/-standard deviation, SD) preoperative IOP was 16.7+/-5.88 mmHg and the mean(+/-SD) postoperative IOP at final visit was 15.5+/-4.07 mmHg. Postoperatively, the IOPs remained well controlled in 20 eyes(90.9%) without additional ocular hypotensives and required additional medications for control in 2 eyes(9.09%). And the funictioning bleb failures occurred in 5 eyes(22.7%). We found the procedure to be effective in restoring vision while controlling intraoperative pressure and preserving the filtering blebs.

Clinical Investigation and Development of Multifocal Posterior Chamber Lens

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.

Clinical Investigation and Development of Multifocal Posterior Chamber Lens

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.

Clinical Result of Iris Claw Lens and Trans-scleral Fixation Technique of Posterior Chamber Lens

Recently, with the development of ophthalmic surgical technique, many of aphakic patients want secondary implantation of intraocular lens. In aphakic eye without posterior capsule, implantation of posterior chamber lens can be performed by sulcus fixation of lens with prolene suture. But sulcus fixation technique has some complications as iP~rmanent fistula, rotation or tilting of the optics, hyphema, endophthalmitis and so on. In this study, 24 aphakic eyes, 22 patients implanted withl itis claw lens were compared with 13 aphakic eyes, 13 patients implanted with sulcus fixated posterior chamber IOLs. In 24 eyes implanted with iris claw lens, 18 eyes (75%) had a postoperative visual acuity of 20/40 or better and cystoid macular edema, intraocular lens dislocation were observed on each 2 eyes (8.3%) and iridodialysis on 1 eye (4.1 %). In 13 eyes implanted with sulcus fixed PCLs, 12 eyes (92%) had a postoperative visual acuity of 20/40 or better, and cystoid macular edema, vitreous hemorrhage, acute iridocyclitis and glaucoma were observed in each 1 case (7.7%). In aphakic eyes without posterior capsular support, iris claw lens will be a alternative method of intraocular lens implantation.

Results of Penetrating Keratoplasty with Scleral-Fixated Posterior Chamber Lens for Aphakic Bullous Keratopathy

Penetrating keratoplasty with or without intraocular lens implantation is necessary to restore a vision of an eye with aphakic bullous keratopathy. We analyzed surgical outcomes in eleven aphakic bullous keratopathy patients(11, eyes) who received penetrat-ing keratoplasty with scleral-fixated posterior chamber lens(PCL)at Kangnam St.Mary's hospital from January, 1989 to December 1991 and followed up more than 1 year Eight of eleven eyes showed the postoperative corrected VlSlOn of 0.3 to 0.8 at postoperative one year. The cuases of poor vision below 0.3 were age-related macular degeneration(1 eye), graft failure(I eye) and diabetic retinopathy(1 eye). At one year after surgery, mean spherical equivalent was-1.12, mean astigmatism was 4.21D and percent loss of corneal endothelium was 35.5%. Graft rejection(3 eyes) and secondary glaucoma(1 eye) were occured during the postoplasty with scleral-fixated PCL can be an excellent surgical technique to get visual rehabilitaion of patients with an aphakic bullous keratopathy.

Posterior Chamber Lens Implantation in High Myopia

We have clinically evaluated 40 cases of high myopia(47 catarctous eyes) with an axial length of over 26 mm which were treated with ECCE and posterior chamber intraocular lens implantation from January 1987 to June 1990 at the 51. Mary's Hospital in the Department of Ophthalmology of Catholic University Medical College. The results were as follows: 1. Most common axial length was from 26.00 mm to 26.50 mm in 24 eyes(51.5%)and most common anterior chamber depth was from 2.51 mm to 3.00 mm in 22 eyes(48.6%). 2. The most common associated diseaes was vitreous opacity(19 eyes: 40.4%). 3. Posterior chamber lens power ranged from +10.00D to +14.00D, and the most frequently implanted posterior chamber lens power was +10.50D. 4. Postoperative corrected visual acuity was the same as preoperative corrected visual acuity in 46 eyes(97.9%) and improved up to 0.5 or more in 31 eyes(66.0%).

Implantation of Posterior Chamber Lens in the Absenee of Posterior Capsular Support

In the implantation of intraocular lens, anterior chamber lenses are usually avoided in glaucoma patients. And because of its close anatomic proximity to the cornea, iris and outflow structures, anterior chamber lense may give rise to more complications as compared with posterior chamber lenses. Thus, the dramatic trend toward clear decrease in the number of anterior chamber lens implantations continues. But despite these complications, the anterior chamber lenses are most often implanted secondarily in the aphakic patients, who, after having had intracapsular cataract extraction or a complicated extracapsular cataract extraction, have lost posterior capsular support. To avoid the many potential complications associated with anterior chamber lenses, attention has shifted toward posterior chamber lens insertion in these cases and particularly in glaucoma patients. From January 1989 to June 1989, we performed newly developed surgical techniques for the implantation of posterior chamber lenses in 7 eyes, including 5 eyes with glaucoma, without posterior capsular support, This was done by securing both haptics of the posterior chamber lens to the sclera at the ciliary sulcus with 10-0 nylon suture. The patients have been followed from 3 to 8 months, all have achieved visual acuity of 20/30 or better without any serious complications, and the postoperative intraocular pressure was well controlled in all 5 eyes with glaucoma.

Clinical Evaluation of Posterior Chamber Intraocular lens Implantation in thee Eye Without Poosterior Capsular Support

The use of a secondary intraocular lens is the best method for the management of spectacle-and contact lenses-intolerant aphakic eye. Because of the high incidence and the great variety of complications associated with anterior chamber lenses, a sulcus-fixed posterior chamber lens is more desirable than an anterior chamber lens. Therefore we have performed newly developed surgical techniques using 25-gauge needle for implanting a posterior chamber lens in the eye without posterior capsular support by securing haptic of the posterior chamber lens to the sclera at the ciliary sulcus with 9~0 prolene suture. These techniques have been sucessfully performed and have produced considerable visual improvement in thirteen aphakic eyes, two patients who had dislocated lens, and two pseudophakic patients who had sun-set syndrome. Eighty-eight percent of the 17 eyes had a postoperative visual acuity of 20/30 or better. The complications in three eyes were transient hyphema, transient vitreitis and exudate in lens surface, and pupillary capture. We have not yet experienced in our series any serious complication, such as lens dislocation, cystoid macular edema, retinal detachment, 2ndary glaucoma, endophthalmitis, and corneal decompensation, but long term follow up and more experience are necessary to establish the safety.

The Effect of Depo-Medrol(R) on Fibrinous Membrane Formation after Posterior Charmber Lens Implantation

I analyzed the incidence of fibrinous membrane formation in the eyes that received extracapsular cataract extraction and posterior chamber lens implantation. There was statistically significant difference between the incidence of fibrinous membrane formation in the eyes that received sub-Tenon's injection of Depo-Medrol(R) at the end of surgery(7.9%) and that in the eyes that did not receive it(34.8%)(p<0.025).

Clinical Results of 125 Eyes of Posterior Chamber Lens Implantation

From February 1986 to October 1988, 125 cases of planned ECCE with posterior chamber lens implantation were performed in Chosun University Hospital, and they had been followed up for more than 6 months. The results were as follows: 1. In the 125 cases of posterior chamber lens implantation, the number of patients were 87 male and 38 female. The most prevalent age groups were age 50s to 60s for both men and women. 2. Posterior chamber lens power ranged from +17.0D to +22.5D and the most frequently used posterior chamber lens power was from +19.0D to +20.0D(83 eyes, 66.4% of 125 cases) in both male and female. 3. Postoperative corrected vision with posterior chamber lens was improved up to 0.6 or better in 87.5%. 4. The mean spherical equivalent o final postoperative refractive state was observed in - 0.75 +/- 1.54D. 5. Postoperative complications were pupil distortion(12.8%), increased intraocular pressure(4.0%), tilted chamber lens(4.0%), cystoid macular edema(2.4%) and after-cataract(1.6%).

Clinical Evaluation of Recent 4 years' Posterior-Chamber Lens Implantation

From October, 1984 to December, 1988, 1177 cases of posterior chamber lens were implanted. Clinical study was done on 1030 cases which could be followed up for more than 2 months. The results were as follows: 1. The best corrected visual acuity of 0.5 or better was in 981 cases(95.2%) and 1.0 or better was in 676 cases(65.6%). 2. the best corrected visual acuity was achieved with the correction of average -1.07 +/- 1.28D by spherical equivalent. 3. The postoperative astigmatism was average 1.57 +/- 1.70D. 4. The difference between the calculated prediction of postoperative refraction and the actual postoperative refraction was less than 1.00D in 64.1% and calculated prediction tended to be biased toward hypermetropia with mean error of 0.37 +/- 1.21D.

Intraocular pressure after extracapsular cataract extraction with implantation of posterior chamber lenses

The intraocular pressure (IOP) in 115 cases of extracapsular cataract extraction (ECCE) and ciliary sulcus fixation of posterior chamber lens implantation was measured more than 2 months postoperatively. These results were compared to the unoperated fellow eyes, as well as to a group of 14 patients who had ECCE and implantation of an anterior chamber lens. The posterior chamber lens implanted eyes demonstrated a significant IOP reduction after surgery compared to the unoperated fellow eyes and the anterior chamber lens implanted eyes. In the posterior chamber lens implanted eyes, there was a significant IOP reduction after surgery in all age groups and there was a significant IOP reduction in the eyes with a 2 to 6 months and a 7 to 12 months follow-up after surgery, but no IOP change in the eyes with more than 1 year follow-up after surgery. We concluded that in the case of ECCE and ciliary sulcus fixation of posterior chamber lens implantation, IOP was initially reduced after surgery, but approarhed the preoperative level over a period of time.