Anterior capsule stability in eyes with intraocular lenses made of poly(methyl methacrylate), silicone, and AcrySof

Three-Dimensional Assessments of Intraocular Lens Stability With High-Speed Swept-Source Optical Coherence Tomography

PURPOSE

To evaluate the effect of intraocular lens (IOL) optic overlapping on IOL stability and to determine the relationship between the capsulorhexis and IOL movement with the three-dimensional method of swept-source optical coherence tomography (SS-OCT).

METHODS

This study identified patients with age-related cataracts and divided them into two groups according to their anterior capsule and IOL optic relationship: total anterior capsule overlap (360°) and partial anterior capsule overlap (< 360°). Standard SS-OCT radial scanning was performed in all eyes at 1 day, 1 week, 1 month, and 3 months after cataract surgery, respectively. The obtained photographs were used for the postoperative position measurements of capsulorhexis and IOL after three-dimensional reconstruction.

RESULTS

This study included 46 eyes of 34 patients: total overlap group (n = 29) and partial overlap group (n = 17). The postoperative aqueous depth significantly decreased in the first week after surgery (P < .001). The IOL tilt was greater in the partial overlap group than that in the total overlap group (P = .014). The IOL moved significantly in the first week postoperatively (both P < .001). IOL decentration in the x-axis was greater in the partial overlap group than that in the total overlap group (P = .024). The IOL and capsulorhexis both moved sharply in the first week (both P < .05). The IOL moved consistently with the capsulorhexis in the 3 months after surgery (all P > .05).

CONCLUSIONS

The total overlap group showed better IOL centrality and stability. IOL movement may be driven by capsular bag contraction and fibrosis. Thus, it was demonstrated that postoperative IOL position and IOL performance were closely linked with proper size of central continuous curvilinear capsulorhexis. [J Refract Surg. 2020;36(6):388-394.].

Unilateral implantation of a new non-diffractive extended range-of-vision IOL in a young patient with Curschmann-Steinert myotonic dystrophy

Purpose

We present the case of a 36-year old Curschmann-Steinert myotonic dystrophy patient with posterior subcapsular cataract that we treated with unilateral implantation of an extended depth of focus intraocular lens to address his wish for spectacle independence at far and intermediate distance.

Observations

The patient underwent phacoemulsification with subsequent implantation of the AcrySof IQ Vivity IOL (Alcon, Fort Worth, TX, USA) in his left eye. Uncorrected distance visual acuity (UDVA) on the left eye increased from +0.40 logMAR preoperatively to −0.12 logMAR at 3 months postoperatively. At the three months follow-up distance corrected intermediate visual acuity (DCIVA) at 80 cm distance was −0.08 logMAR and DCIVA at 66 cm distance was 0.14 logMAR for the left eye. The defocus curve showed a functional defocus of 2.0 diopters at 0.2 logMAR or better, corresponding to the extended depth of focus. Dysphotopsia evaluation with a Halo & Glare simulator (Eyeland-Design Network GmbH, Vreden, Germany) revealed a very low level of photic phenomena.

Conclusions and Importance

Unilateral implantation of a new generation, non-diffractive extended depth of focus IOL was well tolerated and provided good functional results for far and intermediate distances. The patient reported a very low level of photic phenomena.

Changes in Opacification of Hydrophobic Acrylic Intraocular Lenses According to Temperature and Hydration

Purpose

To investigate optic opacification of hydrophobic acrylic intraocular lens (IOL) depending on hydration and temperature conditions.

Methods

IOL (Acrysof^® MA60BM Alcon, Fort Worth, Texas, USA) extracted from a 55-year-old male who underwent binocular cataract 11 years ago were used for the analysis. On slit lamp examination, the binocular IOL optics showed homogenous opacification. After extraction of the IOLs, the IOL opacification disappeared during dry storage at 4°C. To investigate the changes in IOL opacification according to temperature and hydration, an extracted IOL was stored in either dry conditions or normal saline at 4°C, room temperature, or 37°C for 24 hours, and then the degree of haziness was examined. To investigate the impact of an opaque optic on visual function, light transmission was performed using an ultraviolet-visible spectrophotometer (U-3000, Hitachi High-Technologies Corp., Tokyo, Japan).

Results

The extracted IOL optics at 4°C, room temperature, and 37°C were transparent at dry conditions. When the dried IOL was immersed in normal saline at room temperature and 37°C, opacification appeared. However, when the dried IOL was immersed in normal saline at 4°C, opacification of the IOL did not appear. When compared with the control, light transmission of the extracted IOLs from the right and left eyes stored in 37°C normal saline decreased by 4.7% at 453 nm and by 5.1% at 482 nm, respectively.

Conclusion

In acrylic hydrophobic IOLs, optic opacification can occur depending on temperature and hydration conditions.

Effect of capsular tension ring on refractive results in cases with pseudoexfoliation syndrome

PURPOSE

To investigate the effect of capsular tension rings (CTRs) on postoperative refractive results in patients with pseudoexfoliation (PSX) syndrome.

MATERIALS AND METHODS

Sixty-nine patients with PSX syndrome who had uncomplicated cataract surgery between March 2016 and February 2019 were reviewed retrospectively. The patients were divided into two groups. The 35 patients in Group 1 received CTRs prior to intraocular lens implantation during cataract surgery, and the 34 patients in Group 2 had cataract surgery without CTRs. Significant zonular weakness, uncontrolled glaucoma, and ocular pathologies causing low visual acuity were excluded. The preoperative and postoperative keratometry and autorefraction measurements, preoperative expected refractive values, and absolute refractive error were recorded.

RESULTS

The mean ages of patients were 73.54 ± 9.78 years in Group 1 and 72.23 ± 6.72 years in Group 2 (p = 0.521). There was no statistically significant difference between Group 1 and Group 2 in terms of expected preoperative refraction values (-0.52 ± 0.12,-0.56 ± 0.08, respectively, p = 0.118). There was a statistically significant difference in postoperative spherical equivalent values between Group 1 and Group 2 (-0.05 ± 0.97 and -0.92 ± 0.57, respectively, p < 0.01). A statistically significant difference was found between the two groups in terms of absolute refractive error (0.46 ± 0.74 in Group 1 and -0.34 ± 0.59 in Group 2 p < 0.01).

CONCLUSION

CTR implantation causes hyperopic shift, which should be taken into consideration when calculating the lens power of intraocular lens in patients with PSX syndrome.

Measurement of Force Required for Anterior Displacement of Intraocular Lenses and Its Defining Parameters

Intraocular stability during or after cataract and glaucoma filtration surgeries and vitreous surgery with a gas/silicone oil tamponade might differ among intraocular lenses (IOLs). We used six different one-piece IOL models and measured the force that displaced the IOLs from the vitreous cavity to anterior chamber as a measure of stability against the pressure gradient between the anterior and posterior IOL surfaces. We measured IOL hardness, haptics junction area, and posterior IOL bulge to identify what determines the IOL displacement force. The KOWA YP2.2 IOL (1.231 mN) required significantly greater force than the HOYA XY1 (0.416 mN, p = 0.0004), HOYA 255 (0.409 mN, p = 0.0003), Alcon SN60WF (0.507 mN, p = 0.0010), and Nidek NS60YG (0.778 mN, p = 0.0186) IOLs; J&J ZCB00V IOL (1.029 mN) required greater force than the HOYA XY1 (p = 0.0032) and HOYA 255 (p = 0.0029) IOLs; the Nidek NS60YG IOL required greater force than the HOYA 255 (p = 0.0468) IOL. The haptics junction area was correlated positively with the IOL displacement force (r = 0.8536, p = 0.0306); the correlations of the other parameters were non-significant. After adjusting for any confounding effects, the haptics junction area was correlated significantly with the IOL displacement force (p = 0.0394); the IOL hardness (p = 0.0573) and posterior IOL bulge (p = 0.0938) were not. The forces that displace IOLs anteriorly differed among one-piece soft-acrylic IOLs, and the optics/haptics junction area was the major force determinant.

Misdiagnosed opacification of a hydrophobic acrylic intraocular lens

A 75-year-old woman was referred for decreased visual acuity resulting from "opacification of the IOL" in the immediate period after uneventful bilateral cataract surgery with single-piece AcrySof IQ intraocular lens (IOL) implantation. A neodymium:YAG laser capsulotomy had been performed in both eyes to treat the complication. Anterior segment optical coherence tomography performed at presentation showed an opaque membrane enveloping the IOL. The membrane was peeled from the anterior IOL surface, and all adherences between the IOL and capsular bag were freed. One year later, the eyes remained stable; the uncorrected distance visual acuity was 20/20, the IOL was clear, and there was no evidence of recurrence of the membrane. Appropriate imaging for the diagnosis and surgical peeling with freeing of the adhesions between the IOL and the capsular bag were essential to the success in this case.

Comparison of Anterior Capsule Stability Following Implantation of Three Single Piece Acrylic Intraocular Lenses with Different Haptic Design

Purpose

To compare the anterior capsule contraction and intraocular lens (IOL) decentration among three types of IOL to determine the influence of haptic design on anterior capsule stability.

Methods

One hundred fifty patients were enrolled in this prospective, randomized study and 260 eyes underwent implantation of one of the following IOLs: modified L-haptic IOL (n = 74), modified C-haptic IOL (n = 97), or a plate-haptic IOL (n = 89). The area of the anterior capsule opening, IOL decentration, and capsule overlap were measured using retroillumination photospot 1 day and 2 months after cataract surgery.

Results

The area of capsule opening at postoperative day 1 was significantly different between the three IOLs (p < 0.01). All IOLs showed reduction of the anterior capsule opening from 1 day to 2 months after surgery, and greater reduction was shown in the modified C-haptic IOL (p < 0.001). At postoperative month 2, IOL decentration was significantly different between the IOLs and showed a positive correlation with the mean area reduction during month 2.

Conclusions

The degree of anterior capsule contraction and IOL decentration in modified L-haptic IOLs were less than those in modified C-haptic IOLs and comparable to those in plate-haptic IOLs.

Histologic Evaluation of in vivo Femtosecond Laser–Generated Capsulotomies Reveals a Potential Cause for Radial Capsular Tears

Purpose

To compare histologically the size and appearance of capsule disks after femtosecond laser–assisted cataract surgery and conventional cataract surgery.

Methods

In 100 eyes of 100 patients with visually significant cataracts, a femtosecond laser capsulotomy or a capsulorhexis with an aimed diameter of 5.0 mm was performed by one experienced surgeon. The diameter, area, circularity, and cut quality was histologically examined with light microscopy and scanning electron microscopy.

Results

The mean diameter of the manual and the femtosecond laser capsule disk group were not statistically significantly different (manual 4.91 ± 0.34; femtosecond: 4.93 ± 0.03; p = 0.58). The mean area of the capsule disks was 18.85 ± 2.69 mm2 in the manual and 19.03 ± 0.26 mm2 in the femtosecond group (p = 0.64). The capsules of the femtosecond group (0.95 ± 0.02) were significantly more circular than the ones of the manual group (0.81 ± 0.07; p<0.0001). The femtosecond laser capsule disks displayed a more saw blade–like structure created through the single laser spots. The histologic examination combined with prospective video analysis revealed respiratory movement of the eye during the capsulotomy as a potential risk factor for redial tears.

Conclusions

Femtosecond laser can perform a capsulotomy with high reliability. In comparison to a highly experienced cataract surgeon, the achieved results in size are similar. In terms of circularity, the femtosecond laser was superior the manual procedure. Better refractive outcomes based on a 360°-degree optic overlap seem to be possible, especially for less experienced surgeons.

Bimanual anterior segment revision surgery for anterior capsule contraction syndrome associated with anterior flexion of intraocular lens haptics

PURPOSE

To report the incidence of anterior capsule contraction syndrome (ACCS) and to present a novel minimally invasive bimanual technique for anterior segment revision surgery associated with ACCS with anterior flexion of the intraocular lens haptics.

METHODS

A consecutive cohort of 268 eyes of 161 patients undergoing phacoemulsification and implantation of the same type of hydrophilic acrylic aspheric intraocular lens cohort were analysed and a novel technique of minimally invasive bimanual technique for anterior segment revision surgery is described.

RESULTS

We identified four eyes (1.5%) of three patients with advanced ACCS. Successful restoration of a clear visual axis with minimal induction of astigmatism and rapid visual rehabilitation was achieved in all four cases.

CONCLUSION

This technique is a safe and minimally invasive alternative to laser or vitrector-cut capsulotomy to restore a clear visual axis. In cases of advanced ACCS, it offers the option for haptic reposition or amputation.

Effect of haptic material and number of intraocular lens on anterior capsule contraction after cataract surgery

Purpose

To evaluate changes over time of the anterior capsule opening size after phacoemulsification, based on haptic number and composition of three acrylic intraocular lenses (IOLs).

Methods

Fifty-five patients (70 eyes) were included. All underwent phacoemulsification followed by implantation of either an acrylic IOL with two-haptic (one-piece, 26 eyes; three-piece, 22 eyes), or four-haptic (one-piece, 22 eyes). The area of the anterior capsule opening size was measured one week postoperatively (baseline) and at three months.

Results

There was a significant reduction in the area of the anterior capsule opening from one week as compared to three months postoperatively in all groups (p < 0.001). However, there was no significant difference in the reduction in the anterior capsule opening between the IOLs (p = 0.36).

Conclusions

The number and material of the haptic of the three acrylic IOLs did not influence the degree of anterior capsule opening shrinkage.

Anterior capsule relaxing incisions with neodymium:YAG laser for patients at high-risk for anterior capsule contraction

PURPOSE

To examine the effect of anterior capsule relaxing incisions created with a neodymium:YAG (Nd:YAG) laser on prevention of anterior capsule contraction after cataract surgery in high-risk patients.

SETTING

Hayashi Eye Hospital, Fukuoka, Japan.

DESIGN

Randomized masked clinical trials.

METHODS

Patients at high risk for anterior capsule contraction had anterior capsule relaxing incisions in either eye 3 days postoperatively. The anterior capsule opening was measured using a Scheimpflug videophotography system (EAS-1000) immediately and 1, 3, and 6 months after capsulotomy, and the percentage reduction in area was calculated. The degree of intraocular lens (IOL) decentration and tilt, posterior capsule opacification (PCO), and other complications were also assessed.

RESULTS

Of the 84 patients included, 30 had primary angle closure, 28 had pseudoexfoliation, and 26 had diabetic retinopathy. There was no significant difference in the mean opening area between fellow eyes at baseline. In patients with primary angle closure, the area was significantly greater and the percentage reduction in area was significantly less in the capsulotomy group than in the no-capsulotomy group (P≤.0428). In patients with pseudoexfoliation or diabetic retinopathy, the percentage reduction was significantly less in the capsulotomy group than in the no-capsulotomy group (P≤.0493), although there was no significant difference in area. No significant difference was found in IOL decentration or tilt, PCO, or incidence of other complications.

CONCLUSION

Neodymium:YAG laser anterior capsule relaxing incisions in the early period after cataract surgery were effective in preventing anterior capsule contraction in high-risk patients and had no adverse effects.

FINANCIAL DISCLOSURE

No author has a financial or proprietary interest in any material or method mentioned.

Analysis of surface whitening of extracted hydrophobic acrylic intraocular lenses

PURPOSE

To identify the cause of light scattering on the surface (ie, whitening) of extracted AcrySof intraocular lenses (IOLs).

SETTING

Department of Ophthalmology, Dokkyo Medical University, Tochigi, Japan.

METHODS

Dislocated IOLs extracted from 3 patients were stored and the IOL surfaces examined under light microscopy. The effect of whitening on visual function was evaluated by measuring light transmission with a spectrophotometer. To determine the cause of opacification, the IOLs were examined for calcium phosphate deposits using an electron probe X-ray microanalyzer. The IOL surface, including the presence of organic deposits and evidence of hydrolysis, was also examined by Fourier-transform infrared spectrophotometry. The IOLs were then dried, immersed again in physiological saline, and serially examined for changes in opacification.

RESULTS

The optic surfaces of all IOLs had opacification due to whitening. Light transmission in the visible range of 360 to 800 nm was 4% less than that of unused IOLs. The X-ray microanalysis showed no calcium phosphate deposits. Fourier-transform infrared spectrophotometry of the IOL optic material showed no evidence of hydrolysis. Opacification disappeared after the IOLs were dried and then reappeared over time when the IOL was immersed again in physiologic saline.

CONCLUSIONS

The findings strongly suggest that whitening of the hydrophobic acrylic IOL was due to trace water molecules that infiltrate the optic. Within the 3-dimensional network of the polymeric lens material, the molecules are too small to form observable voids but can form water aggregates of sufficient size to scatter visible light, causing opacification (ie, whitening).

Capsular phimosis with complete occlusion of the anterior capsular opening after intact continuous curvilinear capsulorrhexis

Shrinkage and whitening of the anterior capsule opening - capsular contraction syndrome - is a well-known complication after continuous curvilinear capsulorrhexis. A 72-year-old women underwent continuous curvilinear capsulorrhexis, phacoemulsification, and implantation of posterior chamber intraocular lens with polymethylmethacrylate haptics. Four months postoperatively, the patient reported deterioration in visual acuity that was resulted due to complete occlusion of anterior capsular opening by fibrotic tissue. The fibrous membrane was excised surgically in capsulorrhexis fashion.

Prevention of anterior capsule contraction by anterior capsule relaxing incisions with neodymium:yttrium-aluminum-garnet laser

PURPOSE

To examine the effect of two or three neodymium:yttrium-aluminum-garnet (Nd:YAG) laser relaxing incisions made in the anterior capsular rim on prevention of anterior capsule contraction after cataract surgery.

DESIGN

Randomized clinical trials.

METHODS

One hundred patients scheduled for bilateral cataract surgery were randomized to one of two groups: two or three relaxing incisions in the left eye and no incisions in the right eye, and relaxing incisions in the right eye and no incisions in the left eye. The anterior capsule opening area was measured using Scheimpflug photography immediately after capsulotomy and at one, three, and six months after capsulotomy, and the percentage reduction was calculated. The degree of intraocular lens (IOL) decentration and tilt and of posterior capsule opacification (PCO) also were examined.

RESULTS

There was no significant difference in the anterior capsule opening area between fellow eyes at baseline (P > or = .1770). In patients who underwent two incisions, no significant difference was found between fellow eyes in the opening area (P > or = .4098) or in the percentage of reduction (P > or = .8730) throughout follow-up. In patients who underwent three incisions, the opening area in eyes with capsulotomy was significantly greater than that in eyes without capsulotomy (P < or = .0154), and the percentage reduction was significantly smaller in eyes with capsulotomy than in eyes without capsulotomy (P < or = .0016). No significant differences were found in the IOL decentration and tilt, or in PCO.

CONCLUSIONS

Three relaxing incisions made in the anterior capsule decrease the anterior capsule contraction, whereas two incisions do not.

Anterior capsule cover and axial movement of intraocular lens

PURPOSE

To measure optic shift (OS) of a single piece monofocal intraocular lens (IOL) with varying relationships between anterior capsule cover and IOL optic.

METHODS

This is a prospective randomized masked study of 150 eyes undergoing phacoemulsification. Eyes received either option: 360 degrees total capsule cover (group I); partial cover (group II); or no cover (group III). OS was calculated as difference in anterior chamber depth after administration of cyclopentolate 1% and pilocarpine 2% on IOLMaster at separate visits at 6 months follow-up. Subsequently, using retro-illumination photographs, percentage area of capsule cover was calculated. OS within and between groups I and II was analyzed. The impact of one quartile change in area of capsule cover on percentage change in OS was measured for both groups. Unpaired t-test, correlation, and regression were applied.

RESULTS

In groups I, II, and III, mean age of patients was 56.68+/-6.38, 57.09+/-7.34, 59.15+/-6.35 years, respectively; mean OS (mm) was 1.25+/-0.28, 1.20+/-0.24; 0.95+/-0.26 (P=0.013), respectively; and percentage area of capsule cover (%) was 47.35+/-10.48, 33.83+/-10.11, 0.16+/-0.13 (P=0.001), respectively. Mean percentage area of capsule cover in group I vsgroup II was significant (P=0.001). OS was 1.22+/-0.26 mm in groups I and II (combined) vs0.95+/-0.26 mm in group III (P=0.004, (0.06, 0.33)). OS in group I vsgroup II was not significant (P=0.46). Correlation coefficient was r=0.38 (P<0.001). With every increment on quartile (a quartile is any of the three values which divide the sorted data set into four equal parts, so that each part represents one-fourth of the sample or population) class of area of capsule cover the OS increased by 0.12 mm.

CONCLUSION

The OS differed significantly between total and partial cover groups combined vsno cover group.

Capsulorhexis contraction after cataract surgery: Comparison of sharp anterior edge and modified anterior edge acrylic intraocular lenses

PURPOSE

To evaluate the reduction in the anterior capsule opening after phacoemulsification, continuous curvilinear capsulorhexis, and implantation of 1 of 2 acrylic intraocular lenses (IOLs).

SETTING

Department of Ophthalmology, Vejle Hospital, Vejle, Denmark.

METHODS

Eighty-four patients (84 eyes) were included in a prospective randomized study. All had phacoemulsification followed by implantation of an IOL with a modified anterior edge (38 eyes) or a sharp anterior edge (46 eyes). One day (baseline) and 3 months postoperatively, the area of the anterior capsule opening was measured using retroillumination photographs.

RESULTS

There was a significant reduction in the area of the anterior capsule opening from 1 day to 3 months postoperatively in both groups (P<.001). There was no significant difference in the reduction in the anterior capsule opening between the modified-edge IOL and the sharp-edged IOL (P = .313). The shrinkage was independent of the area of the anterior capsule opening at baseline.

CONCLUSIONS

There was a reduction in the area of the anterior capsule opening in all patients. The design of the anterior edge of the 2 IOLs did not influence the degree of anterior capsule opening shrinkage. The shrinkage was independent of the size of the area 1 day postoperatively.

Effect of lens epithelial cell aspiration on postoperative capsulorhexis contraction with the use of the AcrySof intraocular lens

PURPOSE

To determine whether aspiration of lens epithelial cells (LECs) from under the anterior capsule reduces postoperative contraction of the capsulorhexis aperture.

SETTING

Stoke Mandeville Hospital, Aylesbury, Buckinghamshire, United Kingdom.

METHODS

This prospective randomized observer-masked study comprised 100 patients who had routine phacoemulsification by the same surgeon at a district general hospital in the United Kingdom. The postoperative changes in capsulorhexis apertures and anterior capsule opacification (ACO) between Group A (aspiration of LECs) and Group B (control) were compared. Digital retroillumination images of the capsulorhexis aperture were taken 1 week and 3 months postoperatively. The area of capsulorhexis aperture was determined with computer software, and capsule opacification was graded subjectively.

RESULTS

Three months postoperatively, the mean decrease in capsulorhexis aperture was 1.9% in Group A and 5.6% in Group B (P = .02). The ACO at 3 months was grade 2 in 44% of eyes in Group A and in 61% in Group B (P = .13).

CONCLUSION

Aspiration of LECs from the anterior capsule was a safe procedure that reduced capsulorhexis aperture contraction 3 months after cataract surgery.

The effectiveness of Nd:YAG laser capsulotomy for the treatment of posterior capsule opacification in children with acrylic intraocular lenses

INTRODUCTION

Acrylic intraolcular lenses (IOLs) may result in lower rates of posterior capsular opacification (PCO) than poly(methyl methacrylate) lenses in children. Nonetheless, PCO frequently occurs eventually, especially in younger children. Here, we evaluated the success of neodymium-doped yttrium-aluminum-garnet (Nd:YAG) laser capsulotomy for the management of PCO after acrylic IOL implantation without primary capsulectomy.

METHODS

We reviewed 73 eyes in 57 children (age 23 months to 12 years; median, 6.4 years) who underwent Nd:YAG laser capsulotomy after AcrySof IOL implantation and who had at least 3 months follow-up (range, 3-92 months; median, 25 months). The effectiveness of laser treatment was evaluated in terms of the need for repeat laser procedures or intraocular surgery to clear the visual axis.

RESULTS

Fifty-one eyes (70%) maintained a clear visual axis after a single Nd:YAG procedure, 10 eyes (84% cumulative) after 2 Nd:YAG procedures, and another 3 eyes (88% cumulative) after 3 Nd:YAG procedures. Six eyes (8%) required pars plana membrane removal to clear the visual axis, whereas 3 eyes (4%) continue to need treatment. Life table analysis showed that the probability of continuing success after 24 months with a single Nd:YAG procedure is 68% (95% confidence interval 53-83%). In younger children (age<4 years), this rate probability was lower than in older children (35% vs. 74%; P=0.022). Two eyes developed mild transient elevated intraocular pressure. In 1 eye, the IOL was dislocated and replaced.

DISCUSSION

Nd:YAG laser capsulotomy is an acceptable option for the management of PCO after AcrySof IOL implantation in children and produces complications infrequently.

Tilt and decentration of three-piece foldable high-refractive silicone and hydrophobic acrylic intraocular lenses with 6-mm optics in an intraindividual comparison

PURPOSE

Intraindividual comparison of tilt and decentration of three-piece foldable intraocular lenses (IOLs) with 6-mm optics and different edge design and material.

DESIGN

Prospective randomized study.

METHODS

Twenty-five patients with senile cataract (group I) received a foldable silicone, sharp optic edge IOL in one eye and a silicone, rounded optic edge IOL in the other eye. Group II (n = 28) received the foldable silicone, sharp optic edge IOL in one eye and an acrylate, sharp optic edge IOL in the other eye. Scheimpflug photography was performed after the procedure with an anterior eye segment analysis system. Tilt and decentration of the IOL optic were measured 1 week, 6 months, and 12 months after the procedure.

RESULTS

In group I, the foldable silicone, sharp optic edge IOL showed a mean optic tilt of 3.03 +/- 1.79 degrees and an optic decentration of 0.24 +/- 0.13 mm; the silicone, rounded optic edge IOL showed a tilt of 3.26 +/- 1.69 degrees and a decentration of 0.23 +/- 0.13 mm. In group II, the foldable silicone, sharp optic edge IOL showed an average tilt of 2.34 +/- 1.81 degrees and a decentration of 0.29 +/- 0.21 mm after 12 months; the acrylate, sharp optic edge IOL had a tilt of 2.32 +/- 1.41 degrees and a decentration of 0.24 +/- 0.10 mm. There were no significant differences in either group.

CONCLUSION

The examined IOLs showed a stable position regarding tilt and decentration in the first 12 postoperative months, independent of material and edge design. Slight deviations from the optical axis might affect the outcome in aspheric or multifocal IOLs.

Surgical Repositioning of Dislocated Capsular Tension Rings

PURPOSE

To present techniques and results of surgical repositioning of subluxed and dislocated capsular tension rings (CTRs).

DESIGN

Retrospective interventional case series.

PARTICIPANTS

Eleven patients with a previously implanted CTR in-the-bag for zonular weakness who presented with CTR-intraocular lens (IOL)-capsular bag decentration who underwent surgical repositioning.

METHODS

Data from 11 patients who underwent surgical repositioning were evaluated retrospectively for underlying diagnosis, interval between initial surgery and decentration, surgical technique, clinical results, and complications.

MAIN OUTCOME MEASURES

Capsular tension ring-IOL-capsular bag centration, final best-corrected visual acuity (BCVA), and surgical complications.

RESULTS

Of the 11 patients with CTR decentration, 3 had it early in the postoperative period, and 8 had it late. Mean (+/- standard deviation) durations from cataract extraction and CTR implantation to surgical repositioning were 6.1+/-7.9 months for those with decentration early and 49.6+/-15.3 months for late decentrations (overall range, 0.7-74.7). Of the 11 patients, 7 had pseudoexfoliation, and 4 of the 7 had associated glaucoma. Nine patients had subluxation of the CTR-IOL-capsular bag complex, which was managed by an anterior segment approach. A pars plana vitrectomy and levitation of the CTR was required in 2 patients due to complete dislocation of the CTR into the posterior vitreous. Surgical techniques for repositioning included single, double, or 3-point scleral suture loop fixation of the CTR through the capsular bag complex (8 eyes); use of the capsular tension segment (CTS) placed within the capsular bag for scleral suture fixation (2); or iris suture fixation of the IOL haptics (1). All patients achieved successful anatomical repositioning of the CTR-IOL-capsular bag complex. Mean preoperative BCVA improved from 20/100 to 20/40 postoperatively. After repositioning surgery, BCVA improved in 7 patients, was maintained in 2, and worsened in 2 (due to advanced glaucoma).

CONCLUSION

Postoperative CTR subluxation or dislocation is a risk for patients with severe or progressive zonulopathy. Decentrations may be effectively managed with scleral suture fixation of the CTR through the capsular bag or the use of the CTS.

Removal of lens epithelial cells and the effect on capsulorhexis size

PURPOSE

To assess the long-term effects of lens epithelial cell (LEC) removal on capsulorhexis opening size.

SETTING

Dorset County Hospital, Dorchester, United Kingdom.

METHODS

This prospective randomized control study included 39 eyes of 38 patients. Twenty eyes were selected randomly for removal of LECs from the anterior capsule as part of routine cataract operation comprising phacoemulsification with intraocular lens (IOL) implantation. The other 19 eyes were used as controls in which the LECs were not removed. All surgeries were performed by 1 surgeon (A.T.). All patients had silicone IOL (Allergan SI-40) implantation. The capsulorhexis opening size was determined immediately after surgery and 2 weeks and 6 months after surgery. Data on treatment outcome of the cataract surgery were analyzed statistically.

RESULTS

Six months postoperatively, the size of the capsulorhexis had statistically significant increased in the study group that had LECs removed (mean increase 1.07 +/- 1.70 mm(2); paired Student t test P=.01), whereas the capsulorhexis size had statistically significant decreased in the control group (mean decrease -3.38 +/- 2.37 mm(2); paired Student t test, P<.0001). The difference in changes in the capsulorhexis areas between the 2 groups was also highly statistically significant (independent-sample Student t test, P<.0001).

CONCLUSION

Removal of anterior subcapsular LECs by aspiration helped maintain the size of the capsulorhexis opening and thus can help prevent capsule contraction syndrome.

Analyse der optisch wirksamen Parameter nach Kataraktoperation mit Faltlinsenimplantation

PURPOSE

Within the first few weeks after cataract surgery, changes of refraction can occur in patients with "clear cornea" surgery and implantation of foldable lenses. The possible reasons were analyzed.

METHOD

In 71 consecutive patients we determined axial length, anterior chamber depth, corneal refraction, and corneal thickness prior to cataract surgery, on the 1st postoperative day, and at a follow-up control after obtaining stable refraction. We divided the patients into three groups: patients with no change of refraction between the 1st postoperative day and the follow-up (group A), patients with hyperopic shift of refraction (group B), and patients with myopic shift of refraction (group C).

RESULTS

In all three groups we measured no significant postoperative change of the axial length. Central corneal thickness increased by approximately 37 microm on the 1st postoperative day and had normalized at the time of control. Anterior chamber depth decreased in all groups by approximately 0.44 mm between the 1st postoperative day and the follow-up. Central corneal refraction showed an decrease in groups B and C and an increase in group A. The standard deviation was very high in all groups.

CONCLUSIONS

The postoperative change of refraction depends on multiple factors among which changes of the anterior chamber depths, the corneal refraction, the swelling of the cornea, and the axial length can play a role.

Change in IOL position and capsular bag size with an angulated intraocular lens early after cataract surgery

PURPOSE

To investigate the axial movement in the first postoperative week and the influence of capsular bag size with an angulated, 3-piece, open-loop, acrylic intraocular lens (IOL).

SETTING

Department of Ophthalmology, Medical University of Vienna, Vienna, Austria.

METHODS

Twenty-nine eyes of 29 patients with age-related cataract were included in this study. In study 1, an open-loop, 3-piece IOL (AR40e, AMO) was implanted in a standardized fashion in 15 eyes of 15 patients. In study 2, before IOL implantation, a capsular tension ring (CTR) was inserted (14 eyes of 14 patients). Anterior chamber depth (ACD) was assessed with partial coherence interferometry 2 hours; 1, 3, and 5 days; 1 week; and 1 month postoperatively. The capsular bag diameter (CBD) was assessed using gonioscopic measurement of the eyelets of the CTR 1 day, 1 week, and 1 month postoperatively.

RESULTS

In the first postoperative week, there was a significant mean forward movement of -196 microm +/- 117 (SD) (P < .005) in study 1 and -139 +/- 97 microm in study 2 (P < .005). These movements correspond to refractive changes of -0.31 diopter (D) and -0.20 D, respectively. The movement was linear in the first 5 days after surgery. Different patterns of early postoperative movement were seen, illustrating interindividual variability. A significant correlation of 0.67 (P < .05) was found between the change in ACD and CBD.

CONCLUSIONS

A linear forward movement of the IOL during the first postoperative week was followed by a relatively stable IOL position. Loss of haptic memory seemed to be the most likely cause. Myopic eyes with large capsular bags showed less IOL shift in the early postoperative period than hyperopic eyes with smaller capsular bags.

Intraocular lens factors that may affect anterior capsule contraction

PURPOSE

To examine the various factors comprising intraocular lenses (IOLs) that may affect the degree of anterior capsule contraction after cataract surgery.

DESIGN

Randomized controlled clinical trials.

PARTICIPANTS

Three hundred thirty-one patients scheduled for bilateral cataract surgery were studied to compare the degree of anterior capsule contraction in fellow eyes that received different IOLs with regard to the following factors: (1) optic material-acrylic optic versus silicone optic; (2) optic design-round-edge optic versus sharp-edge optic; (3) haptic material-polymethyl methacrylate (PMMA) loop versus polyvinylidene fluoride loop; and (4) haptic material and design-single-piece acrylic haptic versus 3-piece PMMA haptic. The 2 IOLs implanted in the fellow eyes of each patient had almost the same material and design, except for the specific factor being compared.

METHODS

All patients underwent phacoemulsification surgery with implantation of different IOLs in fellow eyes.

MAIN OUTCOME MEASURES

The area of the anterior capsule opening was measured using the Scheimpflug videophotography system at 3 days or 1 week (baseline) and at 1, 3, and 6 months after surgery. The percent reduction in the anterior capsule opening area from baseline was determined at 1, 3, and 6 months after surgery.

RESULTS

The mean percent reduction of the anterior capsule opening area was significantly greater in eyes with a silicone optic IOL than in eyes with an acrylic optic IOL. However, no significant difference was observed in the percent reduction between round-edge and sharp-edge optic IOLs, between PMMA and polyvinylidene fluoride loop IOLs, and between single-piece acrylic and 3-piece PMMA haptic IOLs. Strong associations were found in the percentage between round-edge and sharp-edge optic IOLs, between PMMA and polyvinylidene fluoride loop IOLs, and between single-piece acrylic and 3-piece PMMA haptic IOLs, whereas there was a relatively weak association between silicone and acrylic optic IOLs.

CONCLUSIONS

Among the IOL factors examined, optic material affects most significantly the degree of anterior capsule contraction, whereas optic design and haptic material and design are not strongly related to anterior capsule contraction.

Comparison of the Long-term Clinical Results of Hydrophilic and Hydrophobic Acrylic Intraocular Lenses

This study was performed to compare the incidence of posterior capsular opacity (PCO) and refractive errors between hydrophilic (ACR6D, Corneal) and hydrophobic (MA60BM, AcrySof) acrylic intraocular lenses (IOLs) over a 3-year follow-up after phacoemulsification surgery. The patients with AcrySof implanted in one eye and Corneal in the other eye were categorized as Group 1 (n=28), while those with one or both eyes implanted with IOLs of the same kind were categorized as Group 2 (AcrySof, n=90; Corneal, n=95). Refractive errors were evaluated at 3 months and 3 years postoperatively. The incidence of visually significant PCO was investigated 3 years postoperatively. Postoperative refractive values at 3 months were not significantly different between the two groups. However, refractive values at 3 years were significantly different between two IOLs in both groups [AcrySof -0.37+/-0.43D, Corneal -0.62+/-0.58D in Group 1 (p=0.04); AcrySof -0.38+/-0.52, Corneal -0.68+/-0.54 in Group 2 (p<0.01)]. The incidence of visually significant PCO was 14% and 32% in Group 1, and 13% and 28% in Group 2, for the AcrySof and Corneal implants, respectively. The incidence of visually significant PCO of hydrophilic acrylic IOLs was higher than that of hydrophobic acrylic IOLs in the 3-year follow-up. The postoperative 3-year refractive value of Corneal showed myopic shift.

Clinical Case Notes. Recurrent posterior capsular opacification and capsulorhexis contracture after cataract surgery in myotonic dystrophy

Cataracts are well known to be associated with myotonic dystrophy. Less well known are the phenomena of recurrent posterior capsule opacification and capsulorhexis contracture post cataract surgery. Two cases are described herein of postoperative capsular complications requiring multiple capsulotomies in patients with myotonic dystrophy. It is proposed that a common aetiology may underlie both posterior capsule opacification and capsulorhexis contracture in myotonic dystrophy cases.

Capsular peeling in anterior capsule contraction syndrome: surgical approach and histopathological aspects

We present 4 cases of anterior capsule contraction syndrome in which progressive shrinkage of the anterior capsulorhexis developed after uneventful phacoemulsification. Three eyes were pseudophakic, and 1 eye remained aphakic. The newly formed membrane was surgically peeled from the anterior capsule, restoring the capsular bag.

Use of AcrySof acrylic foldable intraocular lens for secondary implantation in children

PURPOSE

Secondary intraocular lens (IOL) implantation is an increasingly viable option in the management of pediatric aphakia. We report our experience of secondary IOL implantation in pediatric patients using the AcrySof (Alcon Surgical, Fort Worth, Texas) 3-piece foldable lenses through a small incision.

METHODS

We reviewed the records of all our patients < 18 years undergoing secondary IOL implantation of the AcrySof lens from 1997 to 2001. All patients with a minimum of 6 months follow-up were included. Records were analyzed for age at surgery, postoperative acuity change, postoperative refractive error and anisometropia, surgical complications, and length of follow-up.

RESULTS

Fifty-five eyes of 36 patients were included in the review. Mean age at surgery was 7.4 years (1.1 to 15.4), and mean follow-up was 28 months (6.3 months to 5 years). Vision decrease > 2 lines was noted in 3 eyes (5.8%) during the follow-up period. Complications included IOL decentration in 3 eyes (5%), wound leak in 3 eyes (5%), secondary membrane formation in 5 eyes (9%), pupillary block glaucoma in 1 eye (2%), and ptosis in 1 eye (2%). Four eyes (7%) required reoperation for complications. Mean postoperative refractive error was -0.1 +/- 3.2 diopters (D), and mean anisometropia was 2.01 +/- 1.44 D. Glaucoma subsequently developed in 6 eyes (11%), 2 of which required surgical correction.

CONCLUSIONS

Secondary placement of the AcrySof IOL in the ciliary sulcus is a safe and effective method to correct aphakia in pediatric patients with adequate capsular support. The incidence of complications requiring reoperation is low.

Effect of optic edge design and haptic angulation on postoperative intraocular lens position change

PURPOSE

To assess the effect of optic edge design and optic-haptic angulation of open-loop intraocular lenses (IOLs) on postoperative axial movement and the final position of the optic by measuring the anterior chamber depth (ACD) during the first postoperative year using partial coherence interferometry (PCI).

SETTING

Department of Ophthalmology, Vienna General Hospital, Institute of Medical Physics, University of Vienna, Vienna, Austria.

METHODS

In study 1, a 3-piece silicone IOL with nonangulated modified C-loop haptics (MicroSil, Dr. Schmidt) was implanted in 78 eyes of 39 patients; patients were randomized to receive a round-edged optic IOL in 1 eye and a sharp-edged optic IOL in the other eye. The ACD was measured by PCI 1 day, 1 week, 3 months, and 1 year after surgery. In study 2, a foldable, 3-piece acrylic IOL with modified 10-degree angulated J-loop haptics (AcrySof MA60BM, Alcon) was implanted in 32 eyes of 32 patients. The ACD was measured by PCI 1 day, 1 week, and 3 months after surgery.

RESULTS

In eyes with a nonangulated silicone IOL, there was a significant postoperative change in ACD with both sharp-edged and round-edged designs (P<.01). There was forward movement of both IOL designs in the first week, with no significant difference between the 2 models. From 1 week to 3 months, there was backward movement of IOLs of both designs, with the sharp-edged IOL moving a significantly greater amount (P<.001). From 3 months to 1 year, IOLs with both optic edge designs moved slightly backward. Sixty-six percent of angulated IOLs showed continuous but variable forward movement and 34%, backward movement.

CONCLUSIONS

Optic edge design influenced postoperative axial optic movement and thus had an impact on the development of postoperative refraction (refractive shift, deviation from target refraction). The influence of optic-haptic angulation proved to be significantly greater and more variable than edge design.

Effect of haptic design on change in axial lens position after cataract surgery

PURPOSE

To compare the postoperative changes in anterior chamber depth (ACD) between single-piece and multipiece AcrySof intraocular lenses (IOLs) (Alcon Laboratories, Inc.) and their effect on the postoperative refractive shift.

SETTING

Department of Ophthalmology, University of Vienna, Vienna, Austria.

METHODS

This prospective randomized bilateral study with intraindividual comparison comprised 104 eyes of 52 consecutive patients with age-related cataract. All patients had standardized cataract surgery with a temporal self-sealing incision, phacoemulsification, and IOL implantation in the capsular bag. The first 30 patients received a single-piece, 5.5 mm optic IOL (AcrySof SA30) in 1 eye and a multipiece IOL (AcrySof MA30) in the other eye. Another 22 patients received the corresponding 6.0 mm optic models (AcrySof SA60 and AcrySof MA60, respectively). Anterior chamber depth measurements and evaluation of the change in ACD during the first 6 postoperative months were performed using partial coherence laser interferometry. The amount of change in capsulorhexis size during the first 6 postoperative months was assessed using standardized retroillumination photographs.

RESULTS

Single-piece IOLs shifted significantly less postoperatively than multipiece IOLs. The multipiece IOLs shifted forward, especially from 1 day to 1 month. The change in the capsulorhexis area was similar between IOL types.

CONCLUSIONS

Single-piece AcrySof IOLs shifted minimally after the first postoperative day; therefore, the prescription for spectacles in eyes with this IOL can be obtained soon after surgery.

Capsule measuring ring to predict capsular bag diameter and follow its course after foldable intraocular lens implantation

PURPOSE

To evaluate the extent of capsular bag shrinkage after cataract surgery with intraocular lens (IOL) implantation and develop a regression formula to predict postoperative capsular bag size.

SETTING

Eye Hospital, Johannes Gutenberg-University, Mainz, Germany.

METHODS

The axial length (AL), anterior chamber depth, and corneal radius in 58 eyes were measured preoperatively. Cataract surgery was by phacoemulsification followed by implantation of a 3-piece, acrylic, posterior chamber IOL. The capsular bag diameter and anterior capsulorhexis were measured intraoperatively and 1 day and 1, 3, and 6 months postoperatively using a Koch capsule measuring ring (HumanOptics).

RESULTS

The mean capsular bag size was 10.53 mm intraoperatively, 10.31 mm at 1 day, 9.62 mm at 1 month, 9.07 mm at 3 months, and 9.01 mm at 6 months. The mean capsular bag shrinkage over the entire postoperative period was 14.8% (P<.001). Of the parameters studied, only AL had a positive correlation with capsule shrinkage. The correlation was moderate but statistically significant (P =.001).

CONCLUSIONS

A correlation was found between capsular bag shrinkage and AL. Using preoperative biometric data, a regression formula of moderate validity was determined to predict capsular bag shrinkage.

Lens epithelial cell reaction after implantation of different intraocular lens materials

PURPOSE

To determine the influence of intraocular lens (IOL) material on anterior capsular opacification and membrane growth over the anterior IOL surface in patients who have undergone standardized small-incision cataract surgery and foldable IOL implantation in the capsular bag.

DESIGN

Randomized controlled trial.

PARTICIPANTS

Eighty-eight cataract patients (88 eyes).

METHODS

Patients were randomly assigned to receive one of four different foldable IOLs after phacoemulsification: Storz Hydroview H60M, Corneal ACR6D, AMO SI40NB, and Alcon AcrySof MA60BM. Examinations on days 7, 30, 90, 180, 360, and 720 after surgery included ophthalmologic examination, slit-lamp biomicroscopy, and photography using red reflex and focal illumination of the anterior IOL surface.

MAIN OUTCOME MEASURES

Best-corrected visual acuity was measured at each examination. In addition, the anterior capsule opacification and the membrane growth on the anterior IOL surface were graded according to a subjective method by the same researcher.

RESULTS

The fibrosis of the anterior capsule was more frequently observed in the group using Corneal ACR6D and AMO SI40NB. The Hydroview and ACR6D groups showed a higher percentage of cases with membrane growth from the rhexis edge on the anterior IOL surface. AcrySof showed the lowest presence of fibrosis of the anterior capsule, and no membrane growth was noted.

CONCLUSIONS

Anterior capsule opacification is an index of IOL biocompatibility. The natural location of lens epithelial cells (LECs) precludes the possibility of the IOL's design influencing the anterior capsule behavior. The local response of LECs varies according to the IOL studied. This may be related to the chemical and physical properties of the materials used in the different IOLs.

Postoperative change in effective lens position of a 3-piece acrylic intraocular lens

PURPOSE

To study the change in postoperative position of an angulated, 3-piece, foldable acrylic intraocular lenses (IOLs) and evaluate the effect of a sharp posterior optic edge compared with that of a round optic edge on the change in postoperative anterior chamber depth (ACD).

SETTING

Department of Ophthalmology, University of Vienna, Vienna, Austria.

METHODS

This randomized intraindividual-comparison study comprised 104 eyes of 52 patients with age-related cataract. Patient received a sharp-edged Sensar OptiEdge AR40e IOL (Allergan Surgical) in 1 eye and a round-edged Sensar AR40 IOL in the other eye. Postoperative follow-up included ACD measurement by partial coherence interferometry and evaluation of the capsulorhexis area by standardized retroillumination photography at 1 day, 1 week, and 1 and 6 months.

RESULTS

A decrease in ACD during the first postoperative week was followed by a small increase in ACD during the first 6 months. There was no significant difference between the sharp-edged group and the round-edged group.

CONCLUSIONS

The angulated 3-piece acrylic IOLs showed significant forward movement over the first postoperative 6 months. Although the change in refraction was small, there was variability among patients. The sharp posterior optic edge design did not affect the IOL's movement in the capsular bag.

Biocompatibility of intraocular lenses

PURPOSE

The choice of intraocular lens (IOL) implanted by cataract surgeons has significant implications for the effectiveness of the operation and the subsequent need for capsulotomy.

METHODS

Comparison of pertinent peer-reviewed literature published from 1996 through 2001 obtained from a MEDLINE literature search on biocompatibility indicators and IOLs. This review pertains to routine, uncomplicated cataract surgery, and thus, the findings may not be relative to complicated surgeries. Currently available IOLs were not included in this review if no published data on the IOL were available. However, representative lenses from all the major biomaterial classes were included.

RESULTS

Overall results of a comparison of published accounts of posterior capsular opacification, Nd:YAG capsulotomies, anterior capsular opacification, aqueous flare, cellular reaction, capsular adhesion, and capsular stability show a polyacrylic elastomer to be the most highly biointegrated IOLs by the human eye.

CONCLUSIONS

Most evidence published in peer-reviewed journals suggests a clear IOL choice for cataract surgeons. In the field of implantable medical devices, one device in a category does not usually provide consistently superior performance of its intended function. The ability of the biomaterial to maintain a clear optical axis not only by suppressing the proliferation of lens epithelial cells, and thus inhibiting posterior capsular opacification formation and obviating the need for an Nd:YAG capsulotomy, but also by adhering to and stabilizing the capsular bag is, to date, unmatched by any other IOL available.

Surface scattering in implanted hydrophobic intraocular lenses

PURPOSE

To describe surface scattering, a new phenomenon in polyacrylic intraocular lenses (IOLs), and discuss the possible cause of this finding.

SETTING

Showa University, Fujigaoka Hospital, Yokohama, Kanagawa, Japan.

METHODS

This observational case series involved 40 patients who received the AcrySof(R) IOL (Alcon Laboratories, Inc.) as part of a clinical trial in 1991. Four patients (5 eyes) were evaluated. Thirty-three patients had the same surgery in 1999, and the findings in these patients were compared with those in the earlier patients. Lens surface scattering was evaluated by area densitometry using Scheimpflug photography. No statistical analysis was done because of the small sample size.

RESULTS

The 5 IOLs implanted in 1991 showed various degrees of surface scattering. The degree of scattering was greater than that in the 1999 group. There was no degradation in visual performance and no manifestation of intraocular inflammation or other adverse effect from the IOLs in either group. Attempts to remove foreign material on the IOL using the neodymium:YAG (Nd:YAG) laser were unsuccessful.

CONCLUSIONS

The surface scattering did not appear to be due to deposition of foreign material on the IOL surface. Densitometry and the results of Nd:YAG laser treatment suggest that the changes occurred in the near-surface layer. Phase separation of water near the IOL surface in the inherently hydrophobic material may explain the phenomenon. Newer AcrySof IOLs appear to have less surface scattering.

Morphological and functional results of AcrySof intraocular lens implantation in children: prospective randomized study of age-related surgical management

PURPOSE

To evaluate the prevalence and severity of posterior capsule opacification (PCO) in pediatric eyes with a foldable acrylic AcrySof (Alcon) intraocular lens (IOL) and age-related surgical methods.

SETTING

Department of Ophthalmology, University of Vienna, Medical School, Vienna, Austria.

METHODS

This prospective randomized study comprised 50 eyes of 34 children aged between 2 and 16 years. Eyes of children between 2 and 5.9 years were consecutively randomized to Group 1a (primary posterior capsulotomy and anterior vitrectomy) or Group 1b (optic capture in addition). Eyes of children between 6 and 16 years were consecutively randomized to Group 2a (primary posterior capsulotomy without anterior vitrectomy), Group 2b (optic capture in addition), or Group 2c (in-the-bag IOL implantation without opening the posterior capsule). Main outcome parameters were the incidence and severity of PCO formation, early postoperative complications, pigmented cell deposits on the IOL surface, and cataract morphology.

RESULTS

The visual axis was clear at the last follow-up in all eyes in Groups 1a, 1b, 2a, and 2b except in 1 eye in Group 1a. Sixty-percent of eyes in Group 2c had PCO. The incidence of early postoperative complications was significantly higher in eyes that developed PCO than in those that maintained a clear visual axis. There was no evidence that cataract morphology influenced PCO rates.

CONCLUSIONS

The AcrySof IOL was well tolerated in pediatric eyes. Optic capture was not necessary to ensure a clear visual axis. Primary posterior capsulotomy should be performed in preschool and uncooperative children and in eyes expected to have relatively high postoperative inflammation. Implanting the AcrySof in the bag and leaving the posterior capsule intact is acceptable for school children and juveniles with isolated developmental cataract.