The Incidence of after-cataract in Eyes with Silicone and Hydrophilic Acryl-soft IOLs

PURPOSE: To determine the incidence of after cataract. following inserting foldable IOL (silicone or hydrophilic acryl IOL) after phacoemulsification. METHODS: Patients who were diagnosed with senile cataract and had undergone phacoemulsification and foldable IOL (silicone or hydrophilic acryl IOL) insertion were included. Among the respective 80 and 82 subjects, we conducted a prospective study on 51 subjects with silicone IOL and 52 with hydrophilic acryl IOL without complications such as operative posterior capsular rupture, postoperative macular edema and endophthalmitis. We measured the best corrected visual acuity and the development of posterior capsular opacity in 1day, 1month, 3months, 6months, 1year after surgery. RESULTS: The incidence of after catatract was 19.5% (10eyes) in silicone-IOL group and 3.8% (2eyes) in hydrophilic acryl IOL group. Values in two groups showed statistically significant difference. CONCLUSIONS: The incidence of after cataract was lower in hydrophilic acryl IOL group than in silicone IOL group.

A clinical comparison of SI40NB and MA60BM IOLs: One year result

PURPOSE: To evaluate and compare the clinical results of implantation of foldable silicone(SI40NB, PhacoFlexIITM, AMO) intraocular lenses(IOLs) and acrylic(MA60BM, AcrySofTM, Alcon) IOLs. METHODS: Seventy eyes of 35 healthy senile cataract patients who had uneventfully implanted silicone IOL in one eye and acrylic IOL in the other eye were observed on their best corrected visual acuities(BCVA) and postoperative complications such as posterior capsule opacification(PCO) with its incidence and site. RESULTS: Mean postoperative follow-up period was 17.6month +/-2.08(S.D.)(range 13 to 20 months). Postoperative BCVA, with the measurement of above 0.8 was 29% in SI40NB-IOL implanted group(S group) and 37% in MA60BM-IOL implanted group(M group), above 0.5 was 88.4% in S group and 100% in M group. PCO was 19 eyes(54.3%) in S group and 5 eyes(14%) in M group. Anterior capsular contracture was 3 eyes(8.6%) in S group and 1 eye(2.9%) in M group. Two eyes(5.7%) of capsular capture and 3 eyes(8.6%) of decentration(1<1.5 mm) were only in S group. Eight eyes(22.9%) of microvacuole were only in M group. A eye of S group with severe PCO had taken Nd:YAG posterior capsulotomy. To evaluate the PCO character, posterior capsule was imaginary divided into central part and peripheral part at IOL's optic edge. In M group, among 5 eyes(14.3%) of peripheral part opacification, a eye(2.9%) was progressed into central part. In S group, among 19 eyes(54.3%) of peripheral part opacification, 11 eyes(31.4%) were progressed into central part. There was 20% central progression rate in M group and 57.9% in S group. CONCLUSIONS: MA60BM-IOL showed good visual outcome and fewer postoperative complication than SI40NB-IOL, especially in central PCO which is closely related visual outcome.

The Changes in the Area of the Anterior Capsulotomy Size

PURPOSE: To investigate whether there was any difference in anterior capsular opening area between the use of silicone intraocular lens(IOL) and acrylic IOL after continuous curvilinear capsulorhexis(CCC). METHODS: In 42 eyes, acrylic IOL(Acrysof(R), Alcon, U.S.A.) were inserted into the capsular bag during phacoemulsification, and in 36 eyes silicone IOL(Chiroflex II(R) , Chiron, U.S.A.) were inserted. The reduction rate of anterior capsular opening area at first, second, third and sixth postoperative month were compared between the two groups. RESULTS: On the whole, the reduction in anterior capsular opening area was larger by 0.574 mm 2 when silicone IOL was used, but the different was not statistically significant(P= .061). The result was the same at 1 month(P= .149), 2 months(P= .144), 3 months(P= .223), 6 months(P= .163) after surgery. CONCLUSIONS: We concluded that there was little difference in the changes of anterior capsular opening area after CCC between the use of silicone IOL and acylic IOL, and other factors should be considered.

The Apparent Accommodation after Implantation of Posterior Chamber Intraocular Lenses: Acrylic and Silicone

PURPOSE: We compared the apparent accommodative power of acrylic intraocular lens(IOL) with silicone IOL after implantation of IOL into the bag. METHODS: In 36 senile catatact patients(40 eyes)visited St. Mary's hospital from July 1999 to June 2000, the IOL was inserted into the capsular bag after continuous curvilinear capsulorhexis. All of them were over 60 years old. We checked corrected visual acuity, pupil diameter and apparent accommodative power by accommodometer(AA2000, Nidek, Japan) preoperatively and 1 day, 1 month, 2 months after surgery. The used IOLs were two groups, ones are Acrysof (Alcon, U.S.A.) in 20 eyes and the others are Soflex (Chiron vision, U.S.A.) in 20 eyes. RESULTS: The investgation revealed that the apparent accommodative power reached its peak at 1 month after surgery. There was no stastically significant difference(p>0.05) between acrylic IOL and silicone IOL in apparent accommodative power at 2 months after surgery. CONCLUSIONS: The analysis revealed that the pupil size had significant negative correlations with apparent accommodative power at each other group, whereas corrected visual acuity and refraction error showed no relationship with apparent accommodative power.

Three-year follow-up of Clinical Results after SI-30NB Intraocular Lens Implantation Through Temporal Clear Corneal Incision

We examined the clinical results of silicone IOL[SI-30NB]for 3 years or more. A total of 50 eyes underwent phacoemulsification and foldable silicone posterior chamber lens implantation through 3.2 millimeter temporal clear corneal incision. Preoperative and post-operative intraocular pressure, visual acuity, corneal astigmatism and complications were evaluated. More than 94%of all cases showed best corrected visual acuity better than 20/40 and intraocular pressure was decreased for 2 months. At 1 day after operation, mean surgically induced astigmatism was minimal[0.64 +/-1.42]and recovered fast. Posterior capsular opacity was found in 26%;however, Nd-YAG laser capsulotomy was performed in 18%. In conclusion, foldable silicone lens implantation through 3.2 millimetertemporal clear corneal incision revealed a low incidence of complication, minimally induced astigmatism, and rapid visual rehabilitation.

Clinical Comparison between Glaucoma Triple Procedure and Small Incision Cataract Surgery using Foldable silicone IOL

The purpose of this study was to evaluate the postoperative outcomes between the glaucoma triple procedure and the small incision cataract surgery using foldable silicone intraocular lens(IOL). This prospective randomized study comprised of 42 eyes which had the glaucoma triple procedure and 41 eyes which underwent small incision cataract surgery at chonnam University Hospital from May, 1994 to December, 1996. At least 3 months follow-up period was needed. Corrected visual acuity of 0.5 of better was obtained in 50% of triple procedure group and 88% of small incision cataract surgery group with the average lines of improved visual acuity of 5.6 and 7.2 respectively. There was no significant change in the refractive cylinder during the early postoperative period in both group. In the glaucoma triple procedure group, posterior capsular opacification(PCO) developed in significantly low incidence in the Mitomycin C using group and the incidence of PCO in eyes with IOL decentration was greater than in those without IOL decentration. In conclusion, patients who underwent glaucoma triple procedure using foldable silicone IOL showed excellent postoperative IOP control with success rate of 81%, rapid visual rehabilitation and refractive stability. We also found that glaucoma triple procedure with Mitomycin C was associated with lower incidence of PCO.

One-Year Follow-up of 1000 Cases of Silicone Intraocular Lens Implantation

Implantation of silicone intraocular lens(IOL), which is inserted through a small incision, has as its advantages reduced postoperative astigmatism and early visual rehabilitation. It, however, has such disadvantages as unknown long-term biocompatibility, relatively more Nd:YAG laser-induced damage, and unstable fixation. Another difficulty is the possibility of damage to IOL and intraocular tissue during the process of folding and unfolding of the silicone IOL. One thousand cases of the silicone IOL implantation from Sept. 1993 to Mar. 1996 had been followed-up over 1 tear for intraoperative and postoperative complications. Postoperative conditions such as naked visual acuity, and intraocular pressure were also measured. Postoperative naked visual acuity showed fast recovery, with measurements above 20/50 in 71.8% and 85.1% atk postoperative Day 1 and Day 3, respectively. Intraoperative complication was observed in a single case in which an incomplete continuous curvilinear capsulorhexis resulted in cases(7.8%) of posterior capsule opacification requiring Nd:YAG laser posterior capsulotomy. None of the above 57 cases requiring Nd:YAG laser capsulotomy, however, resulted in reduced visual acuity. Other brane(0.4%), pupillary capture of the optic(0.4%), decentration of the IOL(0.3%) and elevated intraocular pressure(0.3%). The silicone IOL implantation showed early visual rehabilitation without severe intraoperative and postoperative complications.

A Clinical Cmparison Silicone and Acrysof IOLs

To evaluate and compare the clinical results of implantation of the Silicone and Acrysof IOLs in early postoperative period(to 3 months), we retrospectively analyzed 30 patients who had taken clear cornea incision and been implanted with Silicone IOL in one eye and Acrysof IOL in the other eye. There were no statistically significant difference in postoperative corrected visual acuity, corneal edema and postoperative astigmatic changes between silicone and acrysof IOLs. But, the rates of postoperative capsular fibrosis and contracture of Silicone IOL was higher than those of Acrysof IOL. In conclusion, in the degree and rate of after-cataract, Acrysof IOLs are more useful than silicone IOLs; therefore, more excellent in longterm visual prognosis. Further studies will be needed for the evaluation of clinical safety and efficacy.

Development of After-cataract in Pseudophakic Eyes with Silicone or PMMA Intraocular Lens

Foldable intraocular lenses(IOLs) arebeing used and wide spread with some advantages such asn little surgically induced astigmatism and rapid visual rehabilitation, but the effect of foldable IOLs on long-term safety and the formation of after-cataract was not understood clearly yet. 48 patients(54 eyes) which underwent Nd-YAG capsulotomy from 1995 to 1997 at the Kangnam St. Mary`s Hostpital were studied. All the cases had been operated by one operator(Joo) with the same technique except for incision method. The average interval from cataract surgery to Nd-YAG capsulotomy was 31 months in PMMA group and 15 months in silicone group. This difference between the two groups was statistically significant(P=0.0002). The ratio of Elschnig pearl type to fibrosis type in after-c attract was 16:6 in PMMA group and 13:18 in silicone group. The average of the total energy used in Nd-YAG laser capsulotomy was 256mJ in PMMA group and 309mJ in silicone group. However, damages caused by YAG laser were severer and more common on the silicone IOLs than on the PMMA IOLs. Silicone IOL induces after-cataract faster than PMMA IOL and the major type of after-cataract in pseudophakia with silicone IOL is fibrosis.

Postsurgical Inflammation Measured with Laser Flare Meter after Silicone or PMMA Intraocular Lens Implantation

It has been reported that silicone intraocular lens(IOL) induces severer and longer intraocular inflammation than polymethylmethacrylate(PMMA) IOL after extracapsular cataract extraction and IOL implantation. In order to evaluate the effect of IOL type on intraocular inflammation the authors measured the aqueous flare intensity by using the laser flare meter(FM 500 Kowa company) from postoperative one day to six months in 100 eyes with phacoemulsification followed by silicone IOL implantation (silicone group) and 100 eyes with phacoemulsification followed by PMMA IOL implantation(PMMA group). Every subject had a simple cataractous lens without systemic disease like diabetes or hypertension. There were no statistically significant differences between two groups in postsurgical aqueous flare intensity during the followed up period(p>0.05). The changes of aqueous flare intensity was spiking on the postoperative one day, declining rapidly in the first week and then keeping a steady state in both groups. Conclusively, we considered that surgically induced inflammation was not influenced by IOL type of PMMA or silicone in cataract operation without complication.

Clinical Results of Silicone Foldable IOL Implanted Through Small Incision

Small incision cataract surgery has many advantages such as less induced corneal astigmatism, fast visual recovery, and fast rehabilitation. We had implatned the newly developed Staar AA-4203 foldable silicone IOL in the ag of 100 cataractous eye and followed for at least 3 months (3-0 months, mean 6 months). Silicone IOLs were implanted using a specific injector through 4mm scleral pocket incision after continuous circular capsulorhexis and bimanual phacoemulsification. The lenses were centered well in 99% of eyes. Tear of anterior capsule occurred in one eye (1%), and tear of both anterior and posterior cassule occurred in another one eye (1%) during IOL implatation. The IOL was displaced into the vitreous in the latter eye, which was reoperated. The preoperative and postoperative cornedal astigmatism at 1 day, 1 month, 2 month and 3 month was -O.14 +/- 0.83 D of with the rule astigmatism (WTR), -0.55 +/- 1.06 D of WTR, -0.28 +/- 0.91 D of WTR, -0.07 +/- 0.81 D of WTR, and O.01 +/- 0.84 D of against the rule astigmatism respectively. Uncorrected VA of 1.0 was 35% at postoperative 1 day, 52% at 1 month, 48% at 2 month. Corrected VA of 1.0 was 65% at postoperative 1 day, 87% at 1 month, 88% at 2 month. Inflammatory reaction in the anterior chamber and vitreous had subsided within one or two months without any complications in 99% of eyes. Fibrinous membrane on the suface of IOL occurred in 2 eyes (2%), one of which caused grave sequelae. The results, although it showed early postoperative results, reflected that the above silicone foldable IOL fitted to the small incision cataract surgery guaranteed us the safety and fast visual recovery.