Comparison of the stability of 1-piece and 3-piece acrylic intraocular lenses in the lens capsule

IOL decentration sensitivity according to spatial frequencies

BACKGROUND/AIMS

Investigation of the decentration sensitivity of monofocal intraocular implants with a focus on different aberration corrections depending on different spatial frequencies.

METHODS

Using an optical bench, the decentration sensitivities of an intraocular lens (IOL) with a high spherical aberration correction of -0.27 µm (ZCB00 Johnson & Johnson), an IOL with an aberration correction of -0.20 µm (Primus HD OphthalmoPro) and an IOL with an aberration neutral design (CT Asphina 409MP Carl Zeiss Meditec) were evaluated for Strehl ratio values and for 25, 50 and 100 lp/mm. Two different corneas with +0.13 µm and +0.28 µm were used. The lenses were tested in the best centration and up to a decentration of 0.5 mm.

RESULTS

Decentration sensitivity affects high spatial frequencies more than lower ones. The possible decentration sensitivity is determined by the amount of spherical aberration of the cornea. The effective decentration sensitivity is determined by the extent to which these spherical aberrations are compensated. If these are not compensated, there is hardly any decentration sensitivity.

CONCLUSION

High spatial frequencies are more affected by decentration sensitivity. The decentration sensitivity of an IOL is determined by the extent to which the spherical aberration of the cornea is corrected.

Influence of Nd:YAG laser capsulotomy on toric intraocular lens rotation and change in cylinder power

PURPOSE

To investigate toric monofocal intraocular lens (TIOL) rotation and associated changes in cylinder power caused by Nd:YAG laser capsulotomy performed due to posterior capsule opacification (PCO).

SETTING

Ekol Eye Hospital, Izmir, Turkey.

DESIGN

Prospective case series.

METHODS

41 eyes of 20 women and 21 men were included in the study. Before and 1 month after Nd:YAG laser capsulotomy, TIOL tilt and decentration were determined with Scheimpflug camera, and TIOL axial rotation and the change in cylinder power induced by this rotation were measured by ray tracing aberrometry. The time interval between cataract surgery and Nd:YAG laser capsulotomy was noted.

RESULTS

Rotational misalignment of the TIOL was measured as 4.65 ± 2.75 degrees (range 0 to 11 degrees) before vs 6.97 ± 2.92 degrees (range 0 to 13 degrees) after capsulotomy, and absolute rotation was 2.75 ± 1.94 degrees (range 0 to 7 degrees, P = .028). Before and after Nd:YAG laser capsulotomy, cylinder power was 0.24 ± 0.70 diopter (D) (range 0.00 to 0.63 D) vs 0.56 ± 0.77 D (range 0.02 to 0.91 D), respectively, with an absolute change in cylinder power of 0.34 ± 0.22 D (range 0.01 to 0.90 D, P = .001). After capsulotomy, there was a significant decrease in IOL tilt in the horizontal and vertical planes and an increase in decentration ( P < .05). Time interval (33.02 ± 12.9 months) and IOL horizontal decentration were independent factors affecting IOL rotation after capsulotomy ( P < .05).

CONCLUSIONS

Nd:YAG laser capsulotomy may cause TIOL rotation as well as tilt and decentration, resulting in a change in the TIOL's corrective effect on corneal astigmatism. Although this change was clinically insignificant, it may be beneficial to consider that TIOL rotational misalignment may occur in patients undergoing early capsulotomy.

Postoperative intraocular lens stability following cataract surgery with or without primary posterior continuous curvilinear capsulorrhexis: an intra-individual randomized controlled trial

PURPOSE

To evaluate the effect of primary posterior continuous curvilinear capsulorrhexis (PPCCC) on the positional stability of IOLs.

METHODS

This study is a prospective intra-individual comparative randomized controlled trial including 31 patients (62 eyes). Eyes of the same patient were randomly assigned to the PPCCC group (18 right eyes and 13 left eyes) or group without PPCCC (NPCCC group). Eyes in both groups were implanted with a one-piece foldable hydrophobic acrylic IOL via routine cataract surgery. Patients in the PPCCC group underwent additional manual PPCCC before IOL implantation. Examinations were performed 1 day, 1 week, 1 month and 3 months postoperatively. IOL tilt (x, y), decentration (x, y), anterior chamber depth (z) and refractive prediction error data were collected and analyzed with Pentacam.

RESULTS

Postoperatively, the range of IOL position change over 3 months in PPCCC group was comparable to NPCCC group, which indicated smaller value in every tilt and decentration index. PPCCC eyes showed comparable tilt and decentration with NPCCC eyes in this study endpoint: mean tilt (x, y), decentration (x, y) and anterior chamber depth (ACD) were 1.04 ± 0.56°, 0.90 ± 0.64°, 0.239 ± 0.140 mm, 0.233 ± 0.133 mm and 4.01 ± 0.32 mm, respectively, in the PPCCC group vs. 1.09 ± 0.76°, 1.10 ± 0.82°, 0.252 ± 0.153 mm, 0.244 ± 0.155 mm and 4.01 ± 0.38 mm, respectively, in the NPCCC group. Refractive prediction error in the PPCCC group demonstrated a mild hyperopic shift vs. the NPCCC group (0.13 ± 0.50 vs. 0.05 ± 0.39; p = 0.208), and corrected distance visual acuity (CDVA) did not differ between the two groups (0.027 ± 0.014 vs. 0.059 ± 0.185; p = 0.377).

CONCLUSIONS

Comparable IOL tilt, decentration, ACD and refractive prediction error were observed in PPCCC eyes with that underwent routine cataract surgery. Little IOL position fluctuation and good visual acuity were shown in PPCCC group over time.

TRAIL REGISTRATION

The study was registered at the Chinese Clinical Trial Register Center on May 27th, 2020 (protocol code ChiCTR2000033304, 27/05/2020).

Long-term Clinical Outcomes After Trifocal Intraocular Lens Implantation: A Retrospective Observational Study

PURPOSE

To evaluate the long-term stability of the AcrySof IQ PanOptix TFNT00 intraocular lens (IOL) (Alcon Laboratories, Inc).

METHODS

This was a retrospective review of 1,065 eyes (745 patients) who underwent implantation of a PanOptix IOL. A total of 296 eyes (mean age: 58.62 ± 5.63 years and preoperative refractive error: -0.68 ± 3.01 diopters [D]) met inclusion criteria for this study. The objective refraction, uncorrected distance and near visual acuity (UDVA and UNVA), and corrected distance visual acuity (CDVA) were evaluated at postoperative months 1, 2, 6, 12, 24, and 36.

RESULTS

The refractive error was -0.20 ± 0.36 D at 1 month, -0.20 ± 0.35 D at 2 months (P = .503), -0.10 ± 0.37 D at 6 months (P < .001), -0.02 ± 0.38 D at 12 months (P < .001), 0.00 ± 0.38 D at 24 months (P < .001), and 0.03 ± 0.39 D at 36 months (P < .001). Multivariate analysis showed long-term, independent associations for young age (beta = -0.122; P = .029) and changes in mean keratometry (beta = -0.413; P < .001). A greater refractive change was associated with a greater change in UNVA (r = 0.134; P = .026) but not with UDVA (r = -0.029; P = .631) or CDVA (r = -0.010; P = .875).

CONCLUSIONS

Implantation of the PanOptix IOL yields stable clinical outcomes for visual acuity and refractive error for the first 3 years. A slight hyperopic shift, causing decreased near visual acuity, is anticipated for younger patients. [J Refract Surg. 2023;39(4):236-241.].

Effects of intraocular lens anterior edge design on anterior capsule morphology changes following femtosecond laser-assisted capsulotomy

PURPOSE

To compare morphological changes in the anterior capsule of two intraocular lenses (IOLs) with different anterior edge designs 6 months after femtosecond laser-assisted capsulotomy surgery (FLACs).

METHODS

This study included 168 eyes from168 patients undergoing FLACs. Group A included 74 eyes from 74 patients who had an Acrysof IQ Restor SN6AD3 IOL implantation with a flat anterior edge and Group B included 94 eyes of 94 patients with a TECNIS Multifocal ZMB00 IOL implantation and a "peak-like" anterior edge. All patients were followed up for 6 months. We assessed anterior capsule morphological changes including variation of anterior opening diameters and lens epithelial cell (LEC) proliferation in four directions, variation of anterior opening area, and the level of anterior capsule opacification (ACO).

RESULTS

Variation of anterior opening diameters in 4 directions were significantly lower in Group B (P < 0.05). Obvious shrinkage ratio of anterior opening diameters and contraction of anterior opening area (P < 0.05) appeared in Group A. LEC proliferation was along the "peak" in Group B, while it spread to the edge of anterior capsule in Group A. ACO grades 6 months after operation in Groups A and B were as follows: grade I in 28.38% and 82.98% of eyes, grade II in 51.35% and 17.02% of eyes, and grade III in 20.27% and 0% of eyes, respectively.

CONCLUSIONS

These findings suggest that a "peak-like" IOL anterior edge design played an important role in maintaining the morphology of anterior capsule in the early postoperative stage.

Predicting Residual Astigmatism in Cataract Surgery

The purpose of this review is to evaluate the prediction of postoperative residual astigmatism and to determine the best prediction method for astigmatism correction. In recent findings for residual astigmatism in non-toric monofocal intraocular lens (IOL) implanted eyes, vector analysis can be used to correctly evaluate residual astigmatism by decomposing it. In predicting residual astigmatism, the with-the-rule (WTR) and against-the-rule (ATR) astigmatism components can now be almost predicted. This may be due to advances in inspection equipment and surgical technique. However, there are still issues with the oblique astigmatism component. In addition, corneal astigmatism is the most important predictor of postoperative residual astigmatism, and other predictors, such as refractive astigmatism, age, and lens thickness, have also been mentioned. However, all but corneal astigmatism are questionable because of the possibility of confounding variables. Total corneal astigmatism is more accurate in predicting residual astigmatism than anterior corneal astigmatism. Several predictions of residual astigmatism have been reported, but complete prediction has not been possible. Further research is needed, especially in predicting oblique astigmatism. However, I emphasize that the accuracy of predicting WTR and ATR astigmatism has improved considerably and can be predicted using regression equations with total corneal astigmatism.

Comparison of two one-piece acrylic foldable intraocular lenses: Short-term change in axial movement after cataract surgery and its effect on refraction

Purpose

To compare the change in intraocular lens (IOL) axial movement, corneal power, and postoperative refraction of eyes implanted with two different single-piece, open loop, acrylic foldable IOLs with planar-haptic design: one IOL with hinges vs. one IOL without hinges. The role of IOL axial movement on short-term refractive shift after cataract surgery was also evaluated.

Methods

This retrospective comparative study enrolled consecutive patients who had phacoemulsification with aspheric IOL implantation. The IOL depth (the distance from corneal endothelium to IOL surface) and corneal power were measured via anterior-segment optical coherence tomography at 4 days and 1 month postoperatively. The changes in axial movement of the IOL, corneal power, and manifest refractive spherical equivalent (MRSE) were compared among groups, and the correlations between each lens were evaluated.

Results

IOL with hinges was implanted in 42 eyes of 42 patients and IOL without hinges was implanted in 42 eyes of 42 patients. The change in axial movement between 4 days and 1 month was significantly smaller in the IOL with hinges group than in the IOL without hinges group (p < 0.001). The axial movement of IOL with hinges did not correlate with the MRSE change; however, the forward shift of IOL without hinges correlated with the myopic refractive change (Pearson r = 0.62, p < 0.001).

Conclusion

The postoperative axial movement of IOL was more stable in the IOL with hinges group than the IOL without hinges group between 4 days and 1 month after cataract surgery. Even though the two study IOLs with planar-haptic design are made of similar acrylic materials, other characteristics such as hinge structure may affect IOL stability in the bag.

Refractive error induced by intraocular lens tilt after intrascleral intraocular lens fixation

PURPOSE

To investigate the spherical shift of intraocular lens (IOL) tilt after intrascleral fixation.

METHODS

We retrospectively reviewed the medical records of patients who underwent flanged intrascleral IOL fixation with transconjunctival 25- or 27-gauge pars plana vitrectomy at the Department of Ophthalmology of the Jikei University Hospital. The minimum follow-up duration was 3 months. Second-generation anterior segment optical coherence tomography (CASIA2; TOMEY) was used to obtain the values of tilt and decentration of the intrasclerally fixated IOL and postoperative anterior chamber depth. We investigated the relationship between refractive error and various parameters, such as IOL tilt and decentration, axial length, and keratometry. In addition to our clinical investigation, we conducted optical simulations using Zemax to evaluate the spherical shift of the IOL tilt by means of the through-focus response and change in spherical equivalent power.

RESULTS

The study involved 72 eyes of 67 patients. The degree of IOL tilt was correlated with the amount of refractive error (Spearman's rank correlation coefficient [CC] = - 0.32; P = 0.006). In particular, a tilt angle greater than 10° strongly affected the refractive error. The postoperative anterior chamber depth also correlated with the refractive error (CC = 0.50; P < 0.001), as opposed to decentration (CC = - 0.17; P = 0.15), axial length (CC = - 0.08; P = 0.49), and keratometry (CC = - 0.06; P = 0.64). Optical simulations also revealed a myopic shift that exponentially increased as the tilt became greater.

CONCLUSION

IOL tilts that are greater than 10° induce refractive error.

Clinical Results of Cataract Surgery Using the ARTIS ® PL E Intraocular Lens

Purpose: To compare the clinical outcomes of cataract surgery using the ARTIS ® PL E (Cristalens Industrie, Lannion, France) intraocular lens (IOL) and conventional Tecnis ® ZCB00 (Johnson & Johnson Vision, Santa Ana, CA, USA) IOL.Methods: This retrospective study examined patients who underwent in-the-bag implantation of either an ARTIS ® PL E (33 eyes, group A) or Tecnis ® ZCB00 (45 eyes, group B) IOL after phacoemulsification performed by a single surgeon. Best-corrected visual acuity (BCVA), spherical equivalent, and higher-order aberrations (HOA) were measured 1 and 3 months after cataract surgery.Results: Preoperative BCVA did not differ significantly in groups A and B. Postoperative BCVA at 1 and 3 months improved significantly (p < 0.001) in both groups compared to preoperative baseline BCVA. At 1 and 3 months postoperatively, total HOA, spherical aberration, and coma were significantly lower compared to the preoperative baseline HOA (p < 0.05) in both groups. However, there were no significant differences in the trefoil values 1 and 3 months postoperatively compared to the preoperative baseline in both groups. The absolute refractive error 3 months postoperatively was 0.27 ± 0.20 (group A) and 0.28 ± 0.20 (group B), both within ± 0.50 diopters of the targeted goal diopter; there were no significant differences in the accuracy or predictability of the IOL power calculation in both groups (p = 0.390, p = 0.959). The absolute refractive error 1 and 3 months postoperatively did not differ significantly; there were no significant differences in the stability of both IOLs (p = 0.482, p = 0.372).Conclusions: Conventional cataract surgery using the ARTIS ® PL E IOL significantly increased the BCVA, while obtaining comparable clinical results to the verified Tecnis ® ZCB00 IOL in postoperative visual acuity and HOA.

Comparison Study of Anterior Capsule Contraction of Hydrophilic and Hydrophobic Intraocular Lenses Under the Same Size Capsulotomy

Purpose

To compare anterior capsule contraction of two kinds of hydrophilic and hydrophobic acrylic intraocular lenses (IOLs) under the same size capsulotomy with femtosecond laser-assisted cataract surgery (FLACS).

Methods

A total of 320 eyes in 320 patients who underwent FLACS were included. The patients were scheduled to have hydrophilic acrylic IOLs (MI60, 509M) and hydrophobic acrylic IOLs (iSert250, ZCB00) implanted. Visual acuity and anterior segment photography using a slit lamp microscope were performed at postoperative one week, one month, three months, and one year.

Results

The contraction of the anterior capsule opening area (mm²) and circumference (mm) in the hydrophilic group were larger than that of the hydrophobic group from postoperative one week to one year (P < 0.001, P < 0.001, respectively). The postoperative contraction of the capsule opening area in MI60 was larger than in 509M (P < 0.001) and larger in 509M than in iSert250 and ZCB00 (P = 0.008, P = 0.019, respectively), but no difference was observed between iSert250 and ZCB00 (P = 0.867). During postoperative one to three months, all groups had the maximum capsule contraction (P < 0.001).

Conclusions

Under the same size capsulotomy with FLACS, the postoperative anterior capsule contraction induced by hydrophobic IOLs was less than that induced by hydrophilic IOLs. Among the four IOLs, the capsule contraction was largest in MI60, followed by 509M, and least in iSert250 and ZCB00, which was time-dependent.

Translational Relevance

Our findings implied that patients with a high risk of ACC should choose hydrophobic IOLs, as well as nonsteroidal anti-inflammatory drugs may be used for a longer period in patients with high risk of capsule contraction syndrome.

Anterior chamber depth variability between 2 hydrophobic acrylic 1-piece intraocular lenses: randomized trial

PURPOSE

To analyze the difference in anterior chamber depth (ACD) after uneventful cataract surgery between 2 hydrophobic acrylic 1-piece intraocular lenses (IOLs) with different material properties.

SETTING

Hanusch Hospital, Vienna, Austria.

DESIGN

Single-center, bilateral randomized paired-eye controlled study.

METHODS

Patients scheduled for bilateral cataract surgery were randomized to receive the Clareon IOL in 1 eye and the AcrySof IQ IOL (both Alcon Laboratories, Inc.) in the contralateral eye. Preoperatively, a slitlamp examination, optical biometry (IOLMaster 700, Carl Zeiss Meditec AG), refraction, and visual acuity measurements were performed. ACD was assessed 1 hour and 1 week postoperatively and with additional measurement of uncorrected (UDVA) and corrected distance visual acuity (CDVA) 6 months postoperatively.

RESULTS

80 eyes of 40 patients were analyzed in this study. ACD at the 6-month follow-up was 3.94 ± 0.30 mm for the Clareon IOL and 3.91 ± 0.32 mm for the AcrySof IQ IOL (P = .08). Statistically significant differences in the ACD shift between both IOLs were detected between 1 week and 6 months (P = .04) and 1 hour and 6 months (P = .04). There were no statistically significant differences between both IOLs in UDVA (P = .78), CDVA (P = .59), and spherical equivalent (SE, P = .39) at the 6-month visit. The mean absolute error between the measured and the aimed SE was not significant (P = .97).

CONCLUSIONS

There was no clinically relevant difference in ACD between the Clareon IOL and the AcrySof IQ IOL in patients after uneventful cataract surgery. Both IOLs yielded good refraction and visual acuity outcomes.

Relationship Between Postoperative Intraocular Lens Shift and Postoperative Refraction Change in Cataract Surgery Using Three Different Types of Intraocular Lenses

Introduction

Understanding the relationship between postoperative intraocular lens (IOL) shift and refractive change is crucial for the accuracy of predicted postoperative refraction (PPR). We assessed the relationships between different IOL fixation methods, haptic designs, and several metrics.

Methods

Single-center, open-label study which included 69 eyes. We preoperatively measured the anterior chamber depth (ACD), lens thickness (LT), axial length (AL), and PPR. AcrySof IQ (n = 27) and FineVision (n = 24) were fixed in the bag, and FEMTIS (n = 18) was fixed in capsulorhexis. At 1 day, 1 week, and 1 month postoperatively, we checked the IOL position and refraction and compared the IOL shift, refraction change, and the margin of error of the predicted PPR (PR-PPR difference). We also analyzed the correlation between postoperative and preoperative variables.

Results

FEMTIS showed the highest stability in terms of IOL shift and refraction. The in-the-bag-fixated IOLs showed a significant forward shift between 1 day and 1 week postoperatively. There were significant differences in the PR-PPR difference between the IOLs. ACD and AL showed significant positive correlations, and LT showed a significant negative correlation with IOL shift and change in PR between 1 day and 1 week, but not between 1 week and 1 month postoperatively.

Conclusion

The relationship between postoperative IOL shift and refraction change varied according to IOLs with different haptic types. Capsulorhexis fixation may be more stable than in-the-bag fixation. Furthermore, preoperative ACD, LT, and AL may be useful factors to predict IOL shift, change in PR, and to a lesser extent the degree of the margin of error in clinical practice. Our findings may improve the accuracy of PPR and refractive outcomes.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40123-021-00390-x.

Long-Term Changes in Manifest Refraction Subsequent to Cataract Surgery

PURPOSE

To examine the long-term refractive changes after stabilization of surgically induced changes (SICs) subsequent to cataract surgery.

SETTING

Private hospital.

DESIGN

Case-control study.

METHODS

Manifest refraction of 300 eyes of 300 patients that underwent phacoemulsification and 300 eyes of 300 age- and sex-matched patients without surgery was examined the day on which SICs stabilized (baseline) and ≥7 years postbaseline using an autorefractometer. Refraction was divided into 3 components: spherical power (M), vertical/horizontal astigmatism (J0), and oblique astigmatism (J45) using power vector analysis, and the components were compared between the 2 time-points and between groups.

RESULTS

In the surgery group, the mean M and J45 did not change significantly between baseline and ≥7 years postbaseline, but the J0 significantly decreased between the 2 time-points (P < .001), indicating an against-the-rule (ATR) shift. In the non-surgery group, the mean M significantly increased and J0 significantly decreased between the time-points (P < .001), whereas J45 did not change significantly. The mean change in M between the 2 time-points was significantly smaller in the surgery group (P < .001), whereas the changes in J0 and J45 did not differ significantly between the time-points.

CONCLUSION

Spherical power did not change and refractive astigmatism significantly changed toward ATR astigmatism during the more than 7-year follow-up after stabilization of SICs in pseudophakic eyes, while hyperopic and ATR shifts occurred in phakic eyes, and the astigmatic changes were comparable between pseudophakic and phakic eyes.

Comparison of decentration, tilt and lenticular astigmatism of ıntraocular lens between sutured and sutureless scleral fixation techniques

PURPOSE

To evaluate at six months the intraocular lens (IOL) decentration, tilt and lenticular astigmatism between foldable sutured and sutureless scleral fixation IOLs compared to conventional phacoemulsification surgery.

METHODS

We retrospectively reviewed records for 22 eyes with sutureless scleral fixation, 16 eyes with sutured scleral fixation and 23 eyes with conventional phacoemulsification. IOL decentration and angle of IOL tilt were compared on Scheimpflug images 6 months after surgery. Lenticular astigmatism is described as the difference between refractive and net corneal astigmatism.

RESULTS

The angle of tilt in both meridians was significantly lower in the sutureless group than in the sutured group (P=0.008 horizontally and P=0.002 vertically). IOL decentration did not show a significant difference between the three groups in either horizontal or vertical meridians (P˃0.05). Lenticular astigmatism was significantly lower in the sutureless and control groups than in the sutured group (P=0.003 and P<0.001).

CONCLUSION

In addition to being relatively quick and easy to perform, the sutureless scleral fixation technique showed superior results in terms of IOL tilt and lenticular astigmatism at the six-month follow-up compared to the sutured technique.

Risk Factor for Transient Hyperopic Refractive Outcome at Acute Postoperative Period After Panoptix Intraocular Lens Implantation

Purpose

To evaluate transient hyperopic refractive outcomes after Acrysof IQ Panoptix TFNT intraocular lens (IOL) implantation and risk factors for transient hyperopia.

Methods

This was a retrospective case review conducted from July 5, 2019, to February 28, 2020, of 203 eyes from 203 patients. The spherical equivalent (SE) on postoperative day 1, week 1, month 1, month 2, and month 6 was evaluated, and the difference between SE (dSE) on postoperative day 1 and month 6 was calculated. Ocular parameters that were associated with a high dSE were evaluated.

Results

This study evaluated 203 eyes from 203 patients (mean age ± SD, 59.14 ± 5.78 years; 129 women [63.5%]). The dSE ± SD was 0.07 ± 0.30 D, 0.14 ± 0.34 D, 0.12 ± 0.35 D, and 0.08 ± 0.35 D for postoperative week 1, month 1, month 2, and month 6, respectively. Univariate analysis revealed that the anterior chamber depth and white-to-white (WTW) corneal diameter were associated with a larger dSE (P = 0.048 and P = 0.03, respectively). Multivariate analysis showed that the WTW diameter was independently associated with the large amount of dSE at 6 months (r = -0.162; P = 0.03).

Conclusion

The results of this study suggest that a smaller WTW corneal diameter was associated with a large dSE between postoperative day 1 and postoperative month 6.

Stability of Various Types of Aspheric Intraocular Lenses After Implantation: A One-Year Retrospective Study

Objective

The aim of the present study was to evaluate the stability of four different types of aspheric intraocular lenses (IOLs) after implantation.

Methods

This retrospective study included 124 eyes implanted with four different types of aspheric IOLs including a one-piece four-loop fixed hydrophilic acrylic IOL, a one-piece flat fixed acrylic IOL, a one-piece two-loop fixed acrylic IOL, and a three-piece two-loop fixed silicone IOL. IOL decentration, tilt, and ocular coma-like aberration (coma) at one-week, one-month, three-month, and one-year time points were evaluated postoperatively.

Results

IOL decentration, tilt, and coma in the AO, 36A, IQ, and KS-AiN implantation groups were statistically significantly different one week and one year postoperatively (p < 0.01). There were significant differences between each of the pairs of groups (p < 0.01), except for coma between the AO and 36A implantation groups one week postoperatively (p > 0.05). When comparing the different time points (ie, one week, one month, three months, and one year postoperatively), IOL decentration, tilt, and coma were significantly different in each group (p < 0.05). IOL decentration, tilt, and coma in each group increased over the period from one week to one year postoperatively. A positive linear correlation was observed between IOL decentration or tilt and coma one year postoperatively (p < 0.01).

Conclusion

One-piece multi-point fixed acrylic IOLs demonstrate better stability when compared with three-piece two-point fixed silicone IOLs. IOL decentration, tilt, and coma increase gradually over time. Ocular coma-like aberrations are influenced by the stability of IOLs.

Temporary changes of visual outcomes and anterior chamber parameters after phacoemulsification and low-add-power segmented intraocular lens implantation for primary angle closure disease

PURPOSE

To evaluate the temporary changes in visual outcomes and anterior segment parameters after cataract surgery plus low-add bifocal intraocular lens (IOL) implantation for primary angle closure disease (PACD).

METHODS

This retrospective comparative case-control study included two groups: low-add-power segmented IOL and monofocal IOL. Postoperative examination involved evaluation of uncorrected distance visual acuity (UDVA), uncorrected near visual acuity (UNVA), uncorrected intermediate visual acuity (UIVA), and spherical equivalent (SE). Anterior segment examination was performed using anterior segment optical coherence tomography.

RESULTS

This study included 19 eyes of 11 consecutive patients who underwent cataract surgery. The low-add group had better UDVA than the monofocal group at 3 months postoperatively, better UIVA at 1 month postoperatively, better UNVA at 1 week postoperatively. In the low-add group, SE increased at 1 and 3 months postoperatively compared with 1 week postoperatively. In the monofocal group, objective SE decreased at 1 and 3 months postoperatively compared with 1 week postoperatively. In the low-add group, the anterior chamber depth (ACD) became significantly deep gradually at 1 and 3 months compared with at 1 week postoperatively. In the monofocal group, the ACD became significantly shallow gradually at 1 and 3 months than at 1 week postoperatively.

CONCLUSION

The low-add-power segmented IOL achieved better far and intermediate distance visual acuity after cataract surgery in PACD patients than did the monofocal IOL. The ACD became deeper and SE showed a hyperopic shift with the low-add-power segmented IOL at 1 and 3 months after cataract surgery compared with at 1 week after cataract surgery.

Secondary Piggyback Intraocular Lens for Management of Residual Ametropia after Cataract Surgery

Purpose

To investigate the indications, clinical outcomes, and complications of secondary piggyback intraocular lens (IOL) implantation for correcting residual refractive error after cataract surgery.

Methods

In this prospective interventional case series, patients who had residual refractive error after cataract surgery and were candidates for secondary piggyback IOL implantation between June 2015 and September 2018 were included. All eyes underwent secondary IOL implantation with the piggyback technique in the ciliary sulcus. The types of IOLs included Sulcoflex and three-piece foldable acrylic lenses. Patients were followed-up for at least one year.

Results

Eleven patients were included. Seven patients had hyperopic ametropia, and four patients had residual myopia after cataract surgery. The preoperative mean of absolute residual refractive error was 7.20 ± 7.92, which reached 0.42 ± 1.26 postoperatively (P< 0.001). The postoperative spherical equivalent was within ±1 diopter of target refraction in all patients. The average preoperative uncorrected distance visual acuity was 1.13 ± 0.35 LogMAR, which significantly improved to 0.41 ± 0.24 LogMAR postoperatively (P = 0.008). There were no intra- or postoperative complications during the 22.4 ± 9.5 months of follow-up.

Conclusion

Secondary piggyback IOL implantation is an effective and safe technique for the correction of residual ametropia following cataract surgery. Three-piece IOLs can be safely placed as secondary piggyback IOLs in situations where specifically designed IOLs are not available.

A Review of Complicated Cataract in Retinitis Pigmentosa: Pathogenesis and Cataract Surgery

Retinitis pigmentosa (RP) is a set of inherited retinal degenerative diseases that affect photoreceptor and retinal pigment epithelial cells (RPEs), possibly associated with some ocular complications, including cataract. The complicated cataract formation is most likely the result of RP-related inflammation response, and the most common morphology category is posterior subcapsular cataract (PSC). Despite the absence of curative pharmacologic treatment, phacoemulsification with intraocular lens implantation to deal with opacification in the lens is preferred due to the considerable visual outcomes. However, the incidence of intraocular and postoperative complications is higher in RP patients than those without, including intraoperative phototoxic retinal damage, posterior capsular opacification (PCO), capsular contraction syndrome (CCS), pseudophakic cystoid macular edema (PCME), increased postoperative intraocular pressure (IOP), and intraocular lens (IOL) dislocation. Hence, it needs much attention to surgery progress and close follow-up. In this review, we discuss the current understanding of RP patients with complicated cataracts from morphology to potential pathogenesis to cataract surgical procedure and provide a concise description and the recommended management of related surgery complications to broaden the knowledge and lower the latent risks to yield better clinical outcomes.

Short-Term Changes in Prediction Error after Cataract Surgery in Eyes Receiving 1 of 3 Types of Single-Piece Acrylic Intraocular Lenses

PURPOSE

To compare short-term changes in refractive prediction error (PE) after phacoemulsification among eyes receiving different types of single-piece acrylic intraocular lenses (IOLs).

DESIGN

Randomized clinical trial.

METHODS

A total of 195 eyes of 195 patients scheduled for implantation of a single-piece acrylic IOL were randomly assigned to receive 1 of 3 IOLs: 1) an Alcon model SN60WF, 2) a Hoya model XY-1, or 3) an AMO model ZCB00V. Manifest spherical equivalent (MRSE) value, PE, and changes in PE were examined at 1 day and at 1 and 2 months postoperatively and were compared among groups.

RESULTS

The mean MRSE and PE significantly changed toward myopia between 1 day and 2 months postoperatively in all groups (P < .0001). The MRSE and PE did not differ significantly among groups at 1 day and 1 month postoperatively and were significantly smaller in the SN60WF group than in the XY-1 and ZCB00V groups at 2 months (P ≤ .0006). The PE change between 1 day and 2 months postoperatively was significantly smaller in the SN60WF group than in the other groups (P = .0062). IOL type and changes in anterior chamber depth and corneal curvature independently correlated with PE changes.

CONCLUSIONS

The MRSE and PE showed a significant myopic change for 2 months postoperatively in eyes implanted with 1 of 3 types of single-piece acrylic IOLs and were significantly smaller in the SN60WF than in the XY-1 and ZCB00V groups. Changes in PE during the 2 postoperative months were smaller in the SN60WF IOLs than in the other IOLs, suggesting that postoperative refractive stability differs among single-piece acrylic IOLs.

The Aravind Pseudoexfoliation Study: 5-Year Postoperative Results. The Effect of Intraocular Lens Choice and Capsular Tension Rings

PURPOSE

We compared rates of intraocular lens (IOL) decentration, neodymium-doped yttrium aluminum garnet capsulotomy for posterior capsule opacification (PCO), and visual acuity (VA) in eyes with and without pseudoexfoliation (PEX) 5 years after undergoing cataract surgery.

DESIGN

Prospective comparative interventional study.

METHODS

This multicenter study population included 1 eye of both 930 cataract patients with and 470 cataract patients without uncomplicated PEX (no small pupils or phacodonesis) all undergoing phacoemulsification by experienced Aravind Eye Care System surgeons. Eyes were randomized to either 1- or 3-piece intraocular lenses (IOLs). PEX eyes were also randomized to either receive or not receive a capsule tension ring. The main outcome measures included IOL decentration and PCO. Secondary outcomes included postoperative best-corrected VA.

RESULTS

Follow-up was 86.2% in the PEX group and 86.7% in the control group at 5 years. The PEX group was older (P < .001) and had more men (P = .01). IOL decentration at 5 years was equally prevalent in PEX and control eyes (1.0% vs 1.1%, respectively, P = .8). Neodymium-doped yttrium aluminum garnet posterior capsulotomy rates for PCO were similar in the PEX group when compared with control subejcts (5.3% compared with 3.2%, respectively, P = .07). Best corrected VA was better at baseline and years 2 and 3 in the control group (P = .0001, P = .0005, and P = .02); however, there was no difference in BCVA at years 1, 4, and 5 between the PEX and control groups (P = .09, P = .29, and P = .5).

CONCLUSION

In a large-scale, long-term, prospective comparative study of cataract surgery in eyes with uncomplicated PEX, the risks of IOL decentration and PCO were low and comparable to that in control subjects. When approaching cataract surgery in eyes with relatively uncomplicated PEX, neither IOL choice (1- vs 3-piece acrylic IOL) nor the presence/absence of a capsule tension ring affects outcomes at 5 years.

Intraocular lens tilt and decentration after Nd:YAG laser posterior capsulotomy: Femtosecond laser capsulorhexis versus manual capsulorhexis

PURPOSE

To compare intraocular lens (IOL) tilt and decentration after Nd:YAG laser posterior capsulotomy in eyes that had femtosecond laser-assisted capsulotomy versus manual capsulorhexis.

SETTING

Ekol Eye Hospital, Izmir, Turkey.

DESIGN

Retrospective case series.

METHODS

Intraocular lens decentration and angle of tilt were measured using a Scheimpflug camera before and 1 month after Nd:YAG capsulotomy.

RESULTS

Eighteen eyes had a femtosecond laser-assisted capsulotomy and 25 eyes a manual capsulorhexis. The mean age was 58.2 years ± 10.2 (SD) (range 44 to 69 years) and 60.6 ± 8.3 years (range 45 to 70 years), respectively. Before capsulotomy, the angle of tilt and decentration at both meridians did not differ significantly between the 2 groups (P > .05). After capsulotomy, the angle of tilt was significantly decreased in both groups (femtosecond: vertical 1.5 degrees and horizontal 1.2 degrees; manual: vertical 1.1 degrees and horizontal) and decentration was significantly increased (femtosecond: vertical 0.085 mm and horizontal 0.096 mm; manual: vertical 0.2 mm and horizontal 0.2 mm) at both meridians (P < .05). After capsulotomy, all tilt and decentration parameters were significantly different between the 2 groups (P < .05) except decentration on the horizontal meridian (P = .669).

CONCLUSIONS

Nd:YAG posterior capsulotomy performed after femtosecond laser-assisted capsulotomy resulted in better mechanical stability of the IOL. This suggests that a femtosecond laser-created capsulotomy better maintains a proper IOL position. Although the differences were statistically significant, the tilt and decentration values were small and might not be clinically significant.

Refractive stability of a new single-piece hydrophobic acrylic intraocular lens and corneal wound repair after implantation using a new automated intraocular lens delivery system

PURPOSE

To investigate refractive stability and characterize corneal incision repair up to 3 months after implantation of a new hydrophobic acrylic intraocular lens (IOL) with hydroxyethylmethacrylate using a new automated IOL delivery system.

METHODS

This prospective case series included 50 eyes of 50 patients undergoing phacoemulsification and implantation of the Clareon® CNA0T0 IOL using the AutonoMe® automated delivery system in the Department of Ophthalmology, Keio University School of Medicine. The clinical data were collected from 46 eyes of 46 patients preoperatively and 1 day, 1 week, and 1 and 3 months postoperatively. Endothelial-side incision gaping, posterior incision retraction, and Descemet's membrane detachment were recorded as present or absent using anterior-segment optical coherence tomography postoperatively.

RESULTS

The uncorrected distance and corrected distance visual acuities improved and stabilized 1 week postoperatively. The anterior chamber depth was stable from 1 week postoperatively. The subjective refraction was stable from 1 day postoperatively. Descemet's membrane detachments and endothelial-side wound gaping were seen in 19 (41.3%) eyes and 34 (73.9%) eyes 1 day postoperatively and decreased gradually. Posterior incision retraction was seen in eight eyes (17.4%) on day 1 and increased to 19 eyes (41.3%) 3 months postoperatively.

CONCLUSIONS

The Clareon IOL had excellent refractive stability from day 1 postoperatively. The AutonoMe automated delivery system enables safe IOL implantation through a 2.4-mm corneal incision, although the wound required longer than 1 month to heal postoperatively.

Effect of manual capsulorhexis size and position on intraocular lens tilt, centration, and axial position

PURPOSE

To evaluate the influence of a manual capsulorhexis size, shape, and position on postoperative axial position, tilt, and centration of intraocular lenses (IOLs).

SETTING

Hanusch Hospital, Vienna, Austria.

DESIGN

Prospective cases series.

METHODS

Patients had cataract surgery and had follow-ups 1 hour and 3 months after surgery. Postoperatively, patients were divided into 3 groups according to the capsulorhexis shape and size as follows: control, symmetrical capsulorhexis between 4.5 mm and 5.5 mm; small group, capsulorhexis smaller than 4.5 mm; and eccentric, all other capsulorhexes. At both follow-ups, a retroillumination image, partial coherence interferometry measurements, and Purkinje meter measurements were performed.

RESULTS

This study comprised 255 eyes. The mean postoperative absolute anterior chamber depth shift in the control, eccentric capsulorhexis, and small capsulorhexis groups was 0.31 mm ± 0.27 (SD), 0.36 ± 0.24 mm, and 0.26 ± 0.24 mm, respectively (P = .419). The mean tilt in the control, eccentric capsulorhexis, and small capsulorhexis groups was 4.08 ± 2.13 degrees, 3.66 ± 2.04 degrees, and 2.82 ± 1.67 degrees, respectively (P = .370), and the mean decentration was 0.38 ± 0.23 mm, 0.40 ± 0.21 mm, and 0.17 ± 0.08 mm, respectively (P = .027).

CONCLUSIONS

Capsulorhexis size and shape had little effect on the capsular bag performance of modern IOLs. Only eyes with a severely malformed capsulorhexis had a slightly decentered IOL.

Comparison of refractive and keratometric astigmatism after microincision cataract surgery

PURPOSE

To measure the correlation between refractive and keratometric astigmatism after microincision cataract surgery (MICS).

SETTING

Takayanagi Clinic, Kushiro, Hokkaido, Japan.

DESIGN

Retrospective case series.

METHODS

This study evaluated patients having phacoemulsification and intraocular lens implantation through a 2.0 mm temporal clear corneal incision. Refractive astigmatism and keratometric astigmatism were described by Jackson cross-cylinder with-the-rule (J0) and oblique (J45) components and compared using linear regression analysis.

RESULTS

The study comprised 90 eyes of 54 patients. The mean postoperative refractive J0 was -0.29 diopter (D) ± 0.46 (SD), and the mean postoperative refractive J45 was -0.09 ± 0.24 D. The multivariate model for the J0 component was postoperative J0 = 0.75 × keratometric J0 + 0.21 × preoperative J0 - 0.23 (R² = 0.85, P < .001). The coefficient of determination of the multivariate model was higher than that of the univariate model (R² = 0.82). The regression equation for the J45 component was postoperative J45 = 0.85 × keratometric J45 - 0.03 (R² = 0.70, P < .001).

CONCLUSION

Refractive astigmatism and keratometric astigmatism after MICS were strongly correlated.

Systematic Study on the Biomechanical Stability of C-Loop Intraocular Lenses: Approach to an Optimal Design of the Haptics

To study the main design parameters that affect the mechanical stability of C-loop intraocular lenses, leading to an optimal design that minimizes the axial displacement, tilt and rotation. A total of 144 geometrical variations were studied on a 1-piece, non-angulated, C-loop hydrophobic acrylate intraocular lens. The study was performed in a finite element modeling simulation. The suitable set of variations was determined using a mixed-factorial analysis, allowing to analyse the impact of the different designs on the mechanical stability of the lens (compression force, axial displacement, tilt and rotation). The design parameters under study were: the length, width, thickness and opening angle of the haptic, the haptic-optic junction and the start of the haptic curvature. The compression (or reaction) force is affected by the haptic width, the haptic-optic junction, and the interaction between both. The axial displacement is mainly affected by the width and thickness of the haptic, and the size of the haptic-optic junction as well. The tilt is affected by the haptic thickness and the interaction between the haptic curvature and the haptic-optic junction. The rotation is affected by the start of the haptic curvature, the haptic-optic junction and the haptic width. The haptic-optic juntion is one of the most influential parameters affecting the four responses studied of the C-Loop IOL. The smaller the haptic-optic juntion, the better biomechanical stability.

Anterior chamber depth - a predictor of refractive outcomes after age-related cataract surgery

Background

Anterior chamber depth (ACD) is becoming a hot topic and plays an important role in correcting the refractive errors (REs) after cataract surgery. The aim of this study was to assess the ACD changes and their relationship with the REs after phacoemulsification and intraocular lens (IOL) implantation in patients with age-related cataracts.

Methods

One hundred forty-five eyes of 125 age-related cataract patients from the Department of Ophthalmology, Tangdu Hospital, China, were recruited. IOL Master was used for axial length (AL) and the IOL power calculation measurements, and the Pentacam HR device was used for the ACD and lens thickness (LT) measurements. Every patient underwent uncomplicated phacoemulsification by a single surgeon using a single technique. Postoperative refraction results were obtained at 1 month. The appropriate formula used for the IOL power calculation was chosen depending on the AL, specifically the Hoffer Q (AL < 22.0 mm), SRK/T (22.0 mm ≤ AL ≤ 30.0 mm), and Haigis (AL > 30.0 mm) formulas.

Results

The postoperative ACD was deepened and tended to stabilize gradually after 2 weeks. A concurrent hyperopic shift (0.57 ± 0.47 D) was observed when the change in the ACD was less than 1.65 mm, whereas a myopic shift (− 0.18 ± 0.62 D) occurred contrarily, and the difference between the two groups was statistically significant (P < 0.0001). The change in ACD was significantly larger in the shallow anterior chamber (1.92 ± 0.40 mm) than in the deep chamber (1.33 ± 0.42 mm) (P < 0.0001). Similarly, the change in ACD was larger in the short AL (2.12 ± 0.37 mm) than in the long AL (1.32 ± 0.49 mm). The postoperative ACD and refractive changes were correlated with the preoperative ACD and AL (P < 0.0001), respectively. Two regression formulas were proposed: postoperative ACD = 3.524 + 0.294 × preoperative ACD and postoperative ACD = 3.361 + 0.228× (preoperative ACD + 1/2 LT).

Conclusions

The results of this study showed that the ACD deepened and was associated with a concurrent RE after cataract surgery. Postoperative changes in the ACD were related to the preoperative ACD and AL, which determined the refraction status and visual quality. The regression formula of the postoperative ACD could provide a theoretical basis for predicting refractive errors in the clinic.

Effects of decentration and tilt on the optical performance of 6 aspheric intraocular lens designs in a model eye

PURPOSE

To compare the effect of decentration and tilt on the optical performance of 6 aspheric intraocular lens (IOL) designs in a model eye.

SETTING

Department of Ophthalmology, Graduate School of Medicine, Dokkyo Medical University, Tochigi, Japan.

DESIGN

Experimental study.

METHODS

In theoretical simulations, the amount of spherical aberration in the IOL was varied to produce residual ocular spherical aberration (range -0.15 to 0.30 μm) at a 6.0 mm entrance pupil. Wavefront aberration analyses were performed with the ZEMAX optical design program (version August 20, 2014) to obtain the ocular root-mean-square values of astigmatism, coma, trefoil, and higher-order aberrations (HOAs) when the IOL was centered on the insertion position and misaligned at a 4.0 mm entrance pupil. The retinal visual images were calculated using the same conditions. Six 20.0 diopter (D) aspheric IOLs and one 20.0 D spherical IOL were used for the experimental studies. Each IOL was inserted in the model eye. The actual alignments were measured using a Scheimpflug camera (EAS-1000). The wavefront aberrations and visual images were gauged using a wavefront analyzer (KR-1W) at several IOL alignments.

RESULTS

Intraocular lens decentration and tilt increased wavefront aberrations and degraded optical performance. Astigmatism, coma, and HOAs generated by misaligned IOLs were related to the amount of spherical aberration correction of the IOLs. The extent of spherical aberration remained unchanged by the amount of misalignment. Experimental model eye results showed trends similar to theoretical results.

CONCLUSIONS

The spherical aberration correction amount in the aspheric IOL design was critical for the astigmatism, coma, and HOAs generated by the IOL misalignment. Additional spherical aberration corrections led to a more sensitive optical performance degradation resulting from IOL misalignment.

Intraocular lens power formula accuracy: Comparison of 7 formulas

PURPOSE

To assess the accuracy of 7 intraocular lens (IOL) power formulas (Barrett Universal II, Haigis, Hoffer Q, Holladay 1, Holladay 2, SRK/T, and T2) using IOLMaster biometry and optimized lens constants.

SETTING

Public hospital ophthalmology department.

DESIGN

Retrospective case series.

METHODS

Data from patients having uneventful cataract surgery with Acrysof IQ SN60WF IOL implantation over 5 years were obtained from the biometry and patient charts. Optimized lens constants were calculated for each formula and used to determine the predicted refractive outcome for each patient. This was compared with the actual refractive outcome to give the prediction error. Eyes were separated into subgroups based on axial length (AL) as follows: short (≤22.0 mm), medium (>22.0 to <24.5 mm), medium long (≥24.5 to <26.0 mm), and long (≥26.0 mm).

RESULTS

The study included 3241 patients. The Barrett Universal II formula had the lowest mean absolute prediction error over the entire AL range (P < .001, all formulas) as well as in the medium (P < .001, all formulas), medium-long (P < .001, except Holladay 1 and T2), and long AL (P < .001, except T2) subgroups. No statistically significant difference was seen between formulas in the short AL subgroup. Overall, the Barrett Universal II formula resulted in the highest percentage of eyes with prediction errors between ±0.25 diopter D, ±0.50 D, and ±1.00 D.

CONCLUSION

In eyes with an AL longer than 22.0 mm, the Barrett Universal II formula was a more accurate predictor of actual postoperative refraction than the other formulas.

FINANCIAL DISCLOSURE

None of the authors has a financial or proprietary interest in any material or method mentioned.

Evaluation of anterior capsular contraction syndrome after cataract surgery with commonly used intraocular lenses

Purpose

The purpose of this study was to compare the incidence of anterior capsular contraction syndrome (ACCS) in cataract patients after implantation with one of two most commonly used hydrophobic acrylic lenses.

Setting

This study included patients from Loma Linda University, Loma Linda, CA, USA.

Design

This study is a retrospective chart review.

Methods

In this study, 1,047 eyes of 811 patients with and without known ACCS risk factors who underwent successful phacoemulsification and intraocular lens (IOL) implantation were included. Eyes that sustained intraoperative capsular tears and patients with a postoperative follow-up of <1 month were excluded. Each patient underwent surgery by the same surgeon receiving either the SN60WF IOL or the ZCB00 IOL. The duration of postoperative follow-up along with the presence of ACCS and the dimensions of the anterior capsule opening in these cases were recorded. The incidence of ACCS between the two lenses was compared.

Results

ACCS was significantly (P=0.045) less frequent in those patients who received the ZCB00 lens compared to those who received the SN60WF lens, despite a significantly greater (P<0.0001) number of patients with ACCS risk factors in the ZCB00 cohort.

Conclusion

In a direct comparison of the ZCB00 and SN60WF IOLs, a lower incidence of ACCS was found with ZCB00 IOL.

Short-term Dynamics after Single- and Three-piece Acrylic Intraocular Lens Implantation: A Swept-source Anterior Segment Optical Coherence Tomography Study

Accurate alignment of an intraocular lens (IOL) is indispensable for achieving accurate postoperative refractive outcomes. Thus, we evaluated decentration and tilt of single- and three-piece IOLs, as well as anterior chamber depth (ACD), at 3 hours, 24 hours, 2 weeks, and 4 weeks after cataract surgery, using swept-source anterior segment optical coherence tomography. There was no significant difference in postoperative visual acuity between eyes with single- or three-piece IOLs. Absolute values of IOL decentration at 24 hours and 2 weeks after surgery were significantly larger (P = 0.008 and 0.046, respectively) in eyes with the single-piece IOL than in those with the three-piece IOL. Both single- and three-piece IOLs tended to tilt toward the inferotemporal direction; however, there was no significant difference in the absolute values of IOL tilt at any postoperative time point. ACD at 24 hours after surgery was significantly deeper (P = 0.009) in eyes with the three-piece IOL, compared with eyes with the single-piece IOL. Therefore, although both single- and three-piece IOL locations varied transiently after surgery, IOL locations were similar between both IOLs at 4 weeks after surgery and were not associated with any statistical difference in visual function.

Effect of number and position of intraocular lens haptics on anterior capsule contraction: a randomized, prospective trial

BACKGROUND

The present study aimed to evaluate the degree of anterior capsule contraction (capsulorhexis contraction) with three different single-piece, hydrophilic acrylic intraocular lenses (IOLs).

METHODS

Patients were prospectively randomized to be implanted with one of three types of IOLs during cataract surgery: the Ophtec Precizon (IOL A), the Lucid Korea Microflex (IOL B), and the Carl Zeiss Asphina (IOL C). One week, 2 weeks, and 6 months after surgery, the area of the anterior capsule opening was measured using digital retro-illumination images after dilation of the pupil. The data were then evaluated using POCOman software.

RESULTS

The study included 236 eyes of 202 patients. The area of the anterior capsule opening reduced by 3.53 ± 3.31 mm (17.06% ± 15.99%) between 1 week and 2 months post-operatively in the IOL A group, by 0.62 ± 1.32 mm (2.87% ± 6.03%) in the IOL B group, and by 1.09 ± 1.53 mm (4.72% ± 6.10%) in the IOL C group. The IOL B group showed minimal anterior capsule contraction 2 months after surgery (p < 0.001).

CONCLUSIONS

IOLs with a four-plate haptic design (IOL B) showed more anterior capsular stability than those with a two-loop plate haptic (IOL A) or two-plate haptic (IOL C) design. The number and position of haptics in a capsular bag may affect anterior capsule contraction. We assume that supporting the zonules evenly may play a role in anterior capsular stability.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN76566080 , Retrospectively registered (Date of registration: 14 Feb 2018).

INTRAOCULAR LENS POSITION IN COMBINED PHACOEMULSIFICATION AND VITREORETINAL SURGERY

PURPOSE

To assess the decentration and angle of tilt of the intraocular lens (IOL) according to the intravitreal tamponade types used in combined phacoemulsification and vitreoretinal surgery.

METHODS

This prospective and randomized clinical study involved 73 eyes of 69 patients who underwent combined vitreoretinal surgery. Eyes with intravitreal tamponades formed the study group and eyes without intravitreal tamponades formed the control group. The study group was further divided into silicone oil and gas tamponade subgroups. Cross-sectional IOL images were captured using a Pentacam HR (Oculus, Germany) and tilt and decentration were calculated with Adobe Photoshop software (Adobe, San Jose, CA).

RESULTS

The mean angle of tilt and decentration at the vertical meridian were significantly higher in both tamponade groups than in the control group (P < 0.05 for all). No significant difference was observed among the groups regarding IOL position parameters at the horizontal meridian (P > 0.05). When comparing the silicone oil and gas tamponade subgroups, no significant differences were noted on the position of IOL at both meridians (P > 0.05 for all).

CONCLUSION

Intravitreal tamponades have an important effect on the position of IOL in combined vitreoretinal surgery. Silicone oil and gas tamponades may induce postoperative tilt and decentration of one-piece acrylic IOLs.

Effects of optical diameter of intraocular lenses with intrascleral fixation on higher-order aberrations

Background

Intrascleral fixation of an intraocular lens (IOL) is used in eyes that lack capsular support. The aim of the study is to determine whether a larger optical diameter IOL will decrease the higher-order aberrations (HOAs) when the haptics are extended for intrascleral fixation than a smaller diameter IOL.

Methods

Three-piece acrylic IOLs with 6.0 mm optics (X-60, VA-60BBR) and 7.0 mm optics (X-70, VA-70 AD) were fixed at lengths of 13, 14, 15, 16, or 17 mm. A wavefront analyzer was used to measure the HOAs within the central 3.0 and 5.2 mm optic diameter.

Results

The astigmatic aberration within the central 5.2 mm was greater than that within the central 3.0 mm for all IOLs. The HOAs increased significantly with an extension of the IOLs with both optical diameters (P < 0.001). The coma aberration within the central 5.2 mm was greater than that within the central 3.0 mm but it did not increase with an extension of the haptics. The astigmatic aberration of the X-60 IOL was significantly greater than that of the X-70 only at an extension of 17 mm. The astigmatic aberration of the VA-70 AD was not significantly different from that of the VA-60BBR. The cylindrical power changed from 0.047 D in the X-60 to 0.118 D in the VA-70 AD when the IOLs were extended from 13 to 17 mm.

Conclusion

When three-piece IOLs are highly extended for intrascleral fixation, the astigmatic aberration increases significantly. However, IOLs with 7 mm optics do not have less astigmatic and coma aberrations than IOLs with 6 mm optics.

Comparison of Intraocular Lens Position Change Following Two Different Implantation Techniques

PURPOSE

To assess the decentration and tilt of one-piece foldable acrylic intraocular lens following two different intraocular lens implantation techniques.

METHODS

This prospective, randomized clinical study conducted on 102 eyes of 91 patients who underwent cataract surgery between September 2015 and May 2016 at Ulucanlar Eye Training and Research Hospital, Ankara, Turkey. Intraocular lens implantations were performed with the help of an ophthalmic viscosurgical device or a hydroimplantation technique during surgery. The main outcomes, which were evaluated one day and one month after surgery, were corrected distant visual acuity, intraocular lens tilt, and decentration at the vertical and horizontal meridians. All outcomes were compared between and within implantation technique groups.

RESULTS

Angle of tilt and decentration of intraocular lens at the vertical and horizontal meridians showed no significant change within the ophthalmic viscosurgical device and hydroimplantation groups during follow-up (p > 0.05 for all). However, intraocular lens at both meridians were significantly lower in the hydroimplantation group (Vertical: p = 0.004, Horizontal: p = 0.015), and intraocular lens decentration tilt at both meridians were significantly lower in the hydroimplantation group than in the ophthalmic viscosurgical device group (Vertical: p = 0.004, Horizontal: p = 0.039). Postoperative corrected distant visual acuity outcomes showed no difference between and within the groups during follow-up (p > 0.05 for all).

CONCLUSIONS

The intraocular lens implantation technique had an important effect on intraocular lens position. The hydroimplantation technique induces central placement of one-piece foldable acrylic intraocular lenses postoperatively by reducing decentration and the angle of tilt.

Posterior Vault Distance of Ciliary Sulcus-Implanted Three-piece Intraocular Lenses According to Ciliary Sulcus Diameter

PURPOSE

To investigate the correlation among preoperative biometry data, postoperative ciliary sulcus diameter, posterior vault distance, and effective lens position of ciliary sulcus-implanted intraocular lenses (IOLs).

DESIGN

Retrospective interventional case series.

METHODS

Twenty-six eyes of 26 patients underwent phacoemulsification with implantation of a ZA9003 IOL (Abbott Medical Optics Inc, Santa Ana, California, USA) in the ciliary sulcus. We analyzed correlations among preoperative biometry data and ultrasound biomicroscopy measurements, ciliary sulcus diameter, posterior vault distance, and effective lens position. Regression analyses were performed to identify which combination of preoperative biometry data, average corneal power (keratometry [K]), anterior chamber depth (ACD), and axial length (AL) was best for predicting effective lens position.

RESULTS

The sulcus diameter was shorter in eyes that had a steep cornea and shorter AL. The posterior vault distance was negatively correlated with sulcus diameter in subjects who had shorter postoperative time intervals (≤24 months) (R² = 0.336 and P = .038). The posterior vault distance decreased with each passing postoperative month (R² = 0.158 and P = .045). The R² value for predicting the effective lens positions of sulcus-implanted IOLs based on the entire average K, ACD, and AL was higher than those based on parts of these values.

CONCLUSIONS

The effective lens position of sulcus-implanted IOLs can be affected by sulcus diameter, and lens position can change, especially in the early postoperative period. We recommend using the entire average K, ACD, and AL to predict the effective position of sulcus-implanted IOLs.

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.

Comparison of refractive error in phacovitrectomy for epiretinal membrane using ultrasound and partial coherence interferometry

PURPOSE

To compare the postoperative refractive error (RE) using A-scan ultrasound (US) and partial coherence interferometry (PCI) after phacovitrectomy for idiopathic epiretinal membrane (iERM) and cataract.

METHODS

Eighty-eight participants (88 eyes) with iERM and cataracts underwent phacovitrectomies with internal limiting membrane removal. Postoperative RE was the main outcome measured, calculated by subtracting intended spherical equivalent (SE) from 6-month postoperative SE. Secondary outcomes included axial length (AL) measured by 2 methods, change in best-corrected visual acuity (BCVA), and change in central subfield thickness (CSFT).

RESULTS

Mean postoperative RE using US showed greater myopic shift compared with that using PCI (-0.569 ± 0.571 D vs -0.169 ± 0.415 D, respectively, p&lt;0.001). The 6-month postoperative RE was within ±0.50 D in 43.2% (38/88) using US vs 84.1% (74/88) using PCI and within ±1.00 D in 84.1% (74/88) using US vs 96.6% (85/88) using PCI. Mean AL measured by US was shorter than that measured by PCI (23.50 ± 1.27 mm vs 23.58 ± 1.30 mm, respectively, p&lt;0.001). Postsurgery, BCVA improved from 0.374 ± 0.264 logMAR to 0.144 ± 0.124 logMAR (p&lt;0.001), and CSFT decreased from 449.2 ± 78.5 µm to 378.2 ± 47.0 µm (p&lt;0.001). The BCVA improvement significantly correlated with decreased CSFT (R = 0.268, p = 0.011).

CONCLUSIONS

Estimation of intraocular lens power for phacovitrectomies for iERM and cataracts is more accurate when assessed by PCI than by US.

Comparison of Ocular Aberrations in Two Hydrophobic and Hydrophilic Intraocular Lenses

OBJECTIVE

To compare differences in higher-order aberrations (HOAs) between two standard spherical monofocal intraocular lenses (IOLs), the hydrophobic acrylic Alcon SA60AT (Bausch & Lomb), and hydrophilic acrylic Rayner Superflex (620H) (Rayner).

METHODS

In this case series, sixty-eight eyes of 68 patients who underwent phacoemulsification cataract surgery were studied. In group 1 (n=39), the hydrophobic Alcon SA60AT IOL, and in group 2 (n=29), the hydrophilic Rayner Superflex (620H) IOL, were implanted. Distant best-corrected visual acuity was 20/20. Aberrometry was performed by the OPD Scan III (Nidek) on the undilated pupil and under mesopic conditions at the first and third months after surgery.

RESULTS

There were no differences between the two groups in the mean total coma, total trefoil, total spherical aberration, and total HOAs in the two follow-up sessions (P>0.5, Independent t test). According to the repeated measure analysis of variance test results, total coma, total trefoil, total spherical aberration, and total HOAs significantly increased over time (P=0.033, P=0.017, P=0.005, P=0.004, respectively), although these changes were not significant between the two groups.

CONCLUSION

It seems that IOL optically behaves differently in vivo versus in vitro conditions and environmental factors can affect the increase or decrease in HOAs by an IOL. Therefore, we should consider these factors and the effect of IOL material and design. Also, the implantation of the Alcon SA60AT and Rayner Superflex IOL does not induce higher HOAs in pseudophakic versus phakic eyes.

Modified Haigis Formula Effective Lens Position Equation for Ciliary Sulcus-Implanted Intraocular Lenses

PURPOSE

To investigate the effect of a modified Haigis formula effective lens position equation on improving refractive outcomes in eyes with ciliary sulcus-implanted intraocular lenses (IOLs).

DESIGN

Retrospective cross-sectional study.

METHODS

One hundred thirty-two eyes of 132 consecutive patients who underwent phacoemulsification with implantation of a ZA9003 (Abbott Medical Optics Inc, Santa Ana, California, USA; 69 eyes) or AR40e (Abbott Medical Optics Inc; 63 eyes) IOL in the ciliary sulcus were enrolled. The modified effective lens position (ELP) equation based on the corneal radius (CR) (ELP - β0 - β1 × CR, where β0 and β1 are parameters in the linear regression analysis) was obtained using linear regression analysis in each IOL group, and was applied to the other IOL group in order to evaluate its effect on refractive outcomes in an independent data set. The median absolute error (MedAE) was predicted using the modified effective lens position equation and was compared with that predicted using the adjusted IOL power.

RESULTS

The modified effective lens position equation was ELP + 11.662 - 1.6225 × CR in the ZA9003 group and ELP + 10.606 - 1.4817 × CR in the AR40e group. The MedAE that was predicted using the modified effective lens position equation (0.34 diopter [D] in the ZA9003 group and 0.42 D in the AR40e group) was significantly smaller than that predicted using the adjusted IOL power (0.47 D in the ZA9003 group and 0.66 D in the AR40e group) (P < .001 and P = .005, respectively).

CONCLUSIONS

IOL power calculation using the modified Haigis formula effective lens position equation improved refractive outcomes in eyes with sulcus-implanted IOLs.

Prospective Comparison of One-Piece and Three-Piece Tecnis Aspheric Intraocular Lenses: 1-year Stability and its Effect on Visual Function

PURPOSE

To compare the stability and visual function of one-piece hydrophobic intraocular lens (IOL) (ZCB00, Abbot Medical Optics) and a three-piece hydrophobic IOL (ZA9003, Abbot Medical Optics) after cataract surgery.

MATERIALS AND METHODS

Eighteen eyes of 18 patients with the one-piece IOL and 20 eyes of 20 patients with the three-piece IOL who underwent cataract surgery were evaluated prospectively on best corrected distance visual acuity, postoperative refractive error, IOL decentration and tilt, anterior chamber depth (ACD), spherical aberration and contrast sensitivity. Measurements were performed 1 week and 1, 3, 6 and 12 months postoperatively. The postoperative outcomes were compared between the two groups.

RESULTS

In the one-piece group, a hyperopic refractive error (p < 0.002) and deeper ACDs during 1-year post-operatively were observed compared with the three-piece group. There were no significant differences in BCVA, IOL tilt, spherical aberration or contrast sensitivity.

CONCLUSIONS

The stability of the one-piece IOL was greater than that of the three-piece IOL. The postoperative ACD and refractive error demonstrated that an anteriorly offset haptic in the one-piece IOL allowed incremental fixation to the posterior capsule.

Misalignment of a novel single-piece acrylic intraocular lens in the first three months after surgery

PURPOSE

To evaluate the misalignment of a new single-piece microincisional hydrophobic acrylic intraocular lens (IOL) in emmetropic, myopic and hyperopic eyes within the first 3 months after surgery.

SETTING

Vienna Institute for Research in Ocular Surgery, Karl Landsteiner Institute, Hanusch Hospital, Department of Ophthalmology, Vienna, Austria.

METHODS

Patients with age-related cataract were included in this prospective study. Each patient received a single-piece microincisional hydrophobic acrylic IOL (AF-1 NY-60, Hoya) in the study eye. Subgroups of emmetropic, myopic and hyperopic eyes were defined according to IOL power calculation. Anterior chamber depth (ACD) measurements were performed with an AC-Master. Tilt and decentration of the IOL were measured with a Purkinje meter. Follow-up assessments were performed 1 h, 3 weeks and 3 months after surgery.

RESULTS

Forty-two eyes of 42 patients (21 emmetropic, 10 myopic and 11 hyperopic eyes) were included. The mean ACD 1 h, 3 weeks and 3 months after surgery was 4.597 ± 0.533, 4.483 ± 0.347 and 4.438 ± 0.398 mm, respectively. Differences in ACD between follow-ups and between subgroups were not statistically significant (both p > 0.05). On average, 3 months after surgery IOLs were tilted 0.81 ± 2.86° nasally and 0.70 ± 3.13° inferiorly and decentered 0.06 ± 0.24 mm nasally and 0.15 ± 0.29 mm superiorly. Differences in tilt and decentration were not statistically significant (both p > 0.05). We observed 1 case of severe capsular fibrosis.

CONCLUSIONS

The single-piece microincisional hydrophobic acrylic IOL showed good axial stability and only little, clinically not relevant tilt and decentration in the first 3 months after surgery.

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.

Intraocular lens position following in-the-bag implantation of single-piece versus three-piece acrylic intraocular lenses

BACKGROUND AND OBJECTIVE

To report the position of the single-piece and three-piece intraocular lenses (IOLs) following in-the-bag implantation.

PATIENTS AND METHODS

Forty patients with bilateral age-related cataracts were recruited from both tertiary hospital and private practice in Montréal, Canada. Patients received the single-piece IOL in one eye and the three-piece IOL contralaterally. Postoperative anterior chamber depth (ACD) and iris-to-IOL distance were evaluated using a Scheimpflug imaging system.

RESULTS

Mean ACD was 4.21 ± 0.32 mm for the single-piece IOL and 3.94 ± 0.34 mm for the three-piece IOL. Mean iris-to-IOL distance was 0.70 ± 0.19 mm for the single-piece IOL and 0.44 ± 0.21 mm for the three-piece IOL. The difference between paired eyes was 0.26 ± 0.20 mm (P = .002) for ACD and 0.25 ± 0.21 mm (P < .001) for iris-to-IOL distance.

CONCLUSION

The single-piece IOL was positioned more posteriorly to the iris and allowed for a greater ACD than the three-piece IOL.