Rotational Stability of Intraocular Lenses: A Standardized Method for More Accurate Measurements in Future Studies.

PURPOSE: To assess the reliability and reproducibility of a new semiautomated evaluation method, "Rotix," for intraocular lens (IOL) rotation and to define a standardized evaluation method for future toric IOL studies. DESIGN: Reliability and reproducibility study. METHODS: Setting: Department of Ophthalmology, Medical University of Vienna. PATIENT POPULATION: A dataset of 25 patients with 2 consecutive follow-up visits was created to test the intra- and interrater reliability. A data test set of 10 patients including 30 pictures taken 5 minutes apart was created to test the short-term reproducibility. INTERVENTION: Evaluation of IOL rotational stability using nontoric implants in 25 × 2 consecutive follow-up visits. Two experienced graders performed axis evaluation 3 times in a randomized order. One experienced grader performed axis evaluation for the short-term reproducibility study. Reference landmarks at the end of operation were used to assess the IOL axis. MAIN OUTCOME MEASURES: Intra- and interrater reliability and short-term reproducibility of axis measurements. RESULTS: Mean standard deviation for intrarater reliability was 0.16 degrees. The intraclass correlation coefficients were 0.97 for grader 1 and 0.96 for grader 2. A very high interrater correlation of 0.95 was found. The mean individual difference between grader 1 and grader 2 was 0.061 ± 0.28 degrees. Short-term reproducibility showed a mean standard deviation of 0.22 ± 0.14 degrees. CONCLUSION: The novel semiautomated evaluation method showed an accurate inter- and intrarater reliability. Short-term reproducibility was below 0.25 degrees. The method of using nonmovable reference landmarks showed reliable results and should be used as a standard in future toric IOL studies.

Comparison of Long-Term Rotational Stability of Three Commonly Implanted Intraocular Lenses.

PURPOSE: To compare rotational stability and its influencing factors in 3 different widely used hydrophobic acrylic intraocular lenses (IOLs) from the end of surgery (EoS) to 4-7 months (6 months) in over 380 eyes. DESIGN: Prospective interventional comparative clinical study. METHODS: Setting: Department of Ophthalmology, Medical University of Vienna. PATIENT POPULATION: A total of 381 eyes of 199 patients with age-related cataract received an IOL Acrysof SN60WF, Tecnis ZCB00, or Envista MX60 in a consecutive order. INTERVENTION: Implantation of an Acrysof, Tecnis, or Envista IOL randomized to the 0 ± 10, 45 ± 10, 90 ± 10, or 135 ± 10° axis in 1 or both eyes. Baseline measurement was performed with patients supine still on the operating table. Postoperative follow-ups were conducted after 1 hour, 1 week, 1 month, and 6 months. MAIN OUTCOME MEASURES: Difference of absolute rotation from the EoS to 6 months. RESULTS: Absolute rotations from the EoS to 6 months were 1.65 ± 2.1, 2.65 ± 4.1, and 3.18 ± 5.8° for the Acrysof, Tecnis, and Envista group, respectively. Rotational stability was statistically significantly superior in the Acrysof compared with the Envista group (P = .014), but not compared with the Tecnis group (P = .10). No significant difference was found between the Tecnis and Envista groups (P = .761). Maximum values of 15.8, 38.6, and 44.9° were observed for the Acrysof, Tecnis, and Envista group, respectively. CONCLUSION: The Acrysof IOL showed the least amount of absolute rotation compared with the Tecnis and Envista IOLs. Outliers possibly requiring secondary intervention were observed in all groups. The amount of rotation was greatest during the first postoperative hour.

Posterior Capsule Opacification With Two Hydrophobic Acrylic Intraocular Lenses: 3-Year Results of a Randomized Trial.

PURPOSE: To compare the incidence and intensity of posterior capsule opacification (PCO) and neodymium-yttrium-aluminum-garnet (Nd:YAG) capsulotomy rates between 2 similar open-loop single-piece hydrophobic acrylic intraocular lenses (IOLs) that differ in the proprietary material characteristics and design features, over a period of 3 years. DESIGN: Randomized, prospective, patient- and examiner-masked clinical trial with intraindividual comparison. METHODS: Setting: Department of Ophthalmology, Medical University of Vienna, Vienna, Austria. PATIENT POPULATION: Eighty patients (160 eyes) had bilateral cataract surgery and received a Vivinex XY1 IOL in 1 eye and an AcrySof SN60WF IOL in the other eye. OBSERVATION PROCEDURES: Follow-up examinations were performed 3 years after surgery. Digital retroillumination images were taken of each eye. The amount of PCO (score: 0-10) was assessed subjectively at the slit lamp and objectively using automated image analysis software (AQUA). MAIN OUTCOME MEASURE: PCO score (scale, 0-10). RESULTS: The mean objective PCO score of the Vivinex XY1 IOLs was 0.9 ± 0.8 compared to the PCO score of 1.4 ± 1.1 for the AcrySof SN60WF IOLs (P < .001). Three years postoperatively, 11.4% of patients had an Nd:YAG capsulotomy in the Vivinex XY1 eye and 18.6% had a capsulotomy in the AcrySof SN60WF eye (P = .23). CONCLUSION: The new hydrophobic acrylic Vivinex XY1 IOL showed significantly lower PCO rates and lower YAG rates compared to the AcrySof SN60WF IOL. The interaction of various factors such as hydrophobic material, smooth optic surface, and sharp posterior optic edge plays a key role in PCO development.

Posterior capsule opacification and Nd:YAG laser rates with two hydrophobic acrylic single-piece IOLs.

OBJECTIVES: To evaluate the development of posterior capsule opacification (PCO) and Nd:YAG capsulotomy rates following implantation of two hydrophobic acrylic IOLs. METHODS: In a randomized, controlled trial, 80 patients with bilateral senile cataract were implanted with the hydrophobic acrylic single-piece intraocular Lenses (IOLs) EyeCee One in one eye and iMics1 in the other. Outcomes of 39 patients (78 eyes) were evaluated after 3 years. Automated Quantification of After-Cataract (AQUA; for PCO occurrence), visual acuity, anterior fibrosis, capsule-optic edge interaction and distance between anterior and posterior capsule IOL surface were analysed. RESULTS: After a mean follow-up of 38 ± 1.95 months, Nd:YAG capsulotomy occurred at a rate of 15.4% and 46.2% in the EyeCee One and iMics1 groups, respectively (p < 0.01). Respective mean PCO scores measured by AQUA were 1.57 ± 1.63 and 2.45 ± 1.44 (p = 0.019). A distinct gap between the anterior capsule and the IOL optic was present in 89% of eyes implanted with EyeCee One and 13% of iMics1 eyes. A gap between the posterior capsule and the posterior surface of the lens was observed in 76% of EyeCee One eyes and 35% of iMics1 eyes. CONCLUSIONS: Study findings suggest that PCO and Nd:YAG capsulotomy rates are significantly lower in eyes implanted with the EyeCee One IOL compared to the iMics1 IOL. Optic sharpness and lens material seem to be the decisive factors, while the stepped edge beneath the haptic junction appeared to be ineffective.

Impact of primary posterior capsulorhexis on regeneratory after-cataract and YAG laser rates with an acrylic micro-incision intraocular lens with plate haptics: 1-year and 3-year results.

PURPOSE: To evaluate the posterior capsule opacification (PCO) and YAG laser capsulotomy (YAG-LCT) rates with a plate-haptic acrylic micro-incision intraocular lens (IOL) and the impact of primary posterior capsulorhexis. METHODS: A total of 97 patients scheduled for immediate sequential bilateral cataract surgery underwent a randomized, prospective intraindividual comparison with the ZEISS Asphina 409MV plate-haptic acrylic IOL with the eyes receiving an additional primary posterior capsulorhexis (PPCR) or not. YAG-LCT and PCO rates were evaluated at 1 and 3 years. Three-year PCO rates were calculated with a 3-scenario method for eyes that underwent YAG-LCT between 1 and 3 years. RESULTS: A total of 56 patients were seen at 1 year, and 57 at 3 years. For the eyes without and with PPCR, YAG-LCT rates were 14.3% and 0% at 1 year, and 59.7% and 3.5% at 3 years, respectively. Opacification rates at 1 year were 0.55 ± 0.99 and 0.05 ± 0.21 for the central 2-mm optic zone. A total of 42 patients completed both the 1- and 3-year follow-up. Three-year opacification rates for the group without PPCR were 1.99 ± 2.20, 2.26 ± 2.66 and 3.66 ± 3.61 for the central 2-mm zone and 2.57 ± 2.07, 3.13 ± 3.03 and 4.09 ± 3.34 for the 4.5-mm zone for the best, extrapolated and worst-case scenarios, respectively. CONCLUSION: The ZEISS Asphina 409MV plate-haptic acrylic IOL exhibited unusually high YAG-LCT and PCO rates with standard in-the-bag implantation. PPCR was safe and effective in preventing central opacification and the need for YAG laser treatment.

True rotational stability of a single-piece hydrophobic intraocular lens.

BACKGROUND: To evaluate rotation and its influencing factors of an aspheric one-piece hydrophobic acrylic intraocular lens (IOL) Vivinex XY1 during 6 months after operation. METHODS: In this institutional trial, 122 eyes of 66 patients were implanted with a non-toric aspheric IOL Vivinex XY1 (Hoya Corporation, Tokyo, Japan). IOL alignment was assessed at the end of surgery, 1 hour, 1 week, 1 month and 6 months after implantation. Confounding factors such as axial length, presence of anterior fibrosis and randomised implantation in four different intended axes (0°, 45°, 90°, 135°) were evaluated. Decentration and tilt were measured using a Purkinje metre. RESULTS: Assessment of rotational stability was possible for 103 of 122 implanted IOLs 6 months after eye surgery. The median absolute rotation was 1.1° (range: 0°-5°). Rotation was significantly increased within the first hour after operation compared with later time-points (p<0.001). No correlation was found with axial length and rotation (Spearman's r=0.048, p=0.63). No significant difference was observed regarding different implantation axes (p=0.75). Rotation was not influenced by the presence of anterior fibrosis (p=0.98). CONCLUSION: Assessing the true IOL position at the end of surgery is crucial for the evaluation of rotational stability of IOLs. No IOL rotation exceeding 5° could be detected 6 months after surgery.

Comparison of posterior capsule opacification development with 2 single-piece intraocular lens types.

PURPOSE: To evaluate the differences in the incidence of posterior capsule opacification (PCO) and visual and optical performance between 2 hydrophobic acrylic single-piece sharp-edged intraocular lenses (IOLs) over 3 years. SETTING: Department of Ophthalmology, Medical University of Vienna, Vienna, Austria. DESIGN: Prospective randomized case series. METHODS: Patients with bilateral cataract were prospectively randomized to receive an Eyecee One IOL (IOL A) or an Acrysof SN60WF IOL (IOL B) and were followed for 36 months. The corrected distance visual acuity (CDVA) and IOL decentration and tilt were measured. The PCO was quantified by analysis of standardized retroillumination images. RESULTS: The study comprised 160 eyes of 80 patients. The PCO incidence was low for both IOLs at all follow-up visits. Three years postoperatively, the median objective PCO score was 1.4 (range 0 to 5.6) for IOL A and 1.5 (range 0 to 5.0) for IOL B (P = .67). The neodymium:YAG (Nd:YAG) capsulotomy rate 3 years after surgery was 16.4% and 6.0% (P = .06), respectively. Visual acuity and contrast sensitivity outcomes were also comparable at all follow-up visits. CONCLUSIONS: Both IOLs showed good capsular bag performance and low PCO rates 3 years after surgery. Both IOLs also showed comparable results for visual acuity, contrast sensitivity, decentration and tilt, PCO score, slitlamp examination, and Nd:YAG capsulotomy rates.

Posterior capsule opacification and neodymium:YAG laser capsulotomy rates with 2 microincision intraocular lenses: Four-year results.

PURPOSE: To compare the development of posterior capsule opacification (PCO) and neodymium:YAG (Nd:YAG) capsulotomy rates between 2 microincision intraocular lenses (IOLs) 4 years after surgery. SETTING: Department of Ophthalmology, Medical University of Vienna, Vienna, Austria. DESIGN: Prospective randomized clinical trial. METHODS: Patients randomly received a Y-60H 3-piece hydrophobic IOL (hydrophobic group) in 1 eye and an MI60 1-piece hydrophilic IOL (hydrophilic group) in the contralateral eye during simultaneous bilateral cataract surgery. Eyes were examined 1 week, 20 months, and 4 years postoperatively. Digital retroilluminated images of each eye were evaluated using Automated Quantification of After-Cataract software. The Nd:YAG laser capsulotomy rate was recorded. RESULTS: Sixty patients were enrolled. Objective PCO was significantly higher in the hydrophobic group than in the hydrophilic group before capsulotomy 2 years after cataract surgery (mean score 2.1 ± 1.8 (SD) versus 1.2 ± 1.4) (P =.031). At the 4-year follow-up, the hydrophobic group had a statistically significantly higher Nd:YAG rate than the hydrophilic group (77% versus 50%) (P =.012). CONCLUSION: Comparison of 2 microincision IOLs indicated a statistically significant difference in PCO and Nd:YAG capsulotomy rates, with very high Nd:YAG rates 4 years after surgery.

Posterior capsular opacification and Nd:YAG capsulotomy rates with the iMics Y-60H and Micro AY intra-ocular lenses: 3-year results of a randomized clinical trial.

PURPOSE: To compare the incidence and intensity of posterior capsular opacification (PCO) and neodymium:yttrium-aluminium-garnet (Nd:YAG) capsulotomy rates between two microincision intra-ocular lenses (IOLs) 3 years after surgery. METHODS: Sixty-five patients randomly received a Y-60H IOL (HOYA Surgical Optics, Singapore) in one eye and a Micro AY IOL (PhysIOL, Liège, Belgium) in the contralateral eye during same-day bilateral cataract surgery. Eyes were examined 1 week, 20 months and 3 years after surgery. The amount of PCO (score: 0-10) was assessed subjectively at the slit lamp and objectively using automated image analysis software (aqua). Additionally, the Nd:YAG capsulotomy rate was noted. RESULTS: Three years postoperatively, the objective PCO score of Y-60H IOLs was 1.9 ± 1.7 compared to PCO score of 1.7 ± 2.2 for the Micro AY IOLs (p = 0.66). Thirty-four percentage of the Y-60H eyes had undergone Nd:YAG capsulotomy, compared to 49% of the Micro AY eyes (p = 0.04). Significantly, more capsular folds were observed in the Y-60H IOL group (p = 0.001). There was no significant difference in best-corrected visual acuity, rhexis/IOL overlap and anterior capsule opacification 3 years after surgery. CONCLUSION: Both microincision IOLs showed high YAG rates and comparable PCO scores 3 years after surgery. In the light of this unsatisfying PCO performance, the advantage of the present microincision IOLs over conventional IOLs must be questioned.

Impact of low versus high fluidic settings on the efficacy and safety of phacoemulsification.

PURPOSE: To compare intraoperative efficiency and postoperative outcomes of cataract surgery with low and high fluidic settings. METHODS: In this prospective, randomized, single-blinded study, 114 eyes of 57 patients were operated with low fluidic settings for one eye (group I) and high fluidic settings for the other eye (group II). Efficiency was judged as metred surgery time, effective phacoemulsification time (EPT) and the amount of balanced salt solution used. Visual outcome and endothelial cell count were determined 1 week and 18 months postoperatively. RESULTS: The overall effective phacoemulsification energy was statistically significantly lower (p = 0.003) in group II than in group I. Conquest of the nuclei was achieved with about two-thirds of the energy needed in group I, with 6.59 ± 4.79 effective ultrasound energy compared with 3.99 ± 3.18 (p = 0.001). Overall, about 12% more solution was used in group II than in group I. Median visual acuity was 1.0 for both groups 18 months after surgery. The mean endothelial cell loss was 5.0% in eyes in group I compared with 6.3% in eyes in group II (p > 0.5). CONCLUSION: Switching from low fluidic settings with a conventional coaxial 20G phacoemulsification tip to higher fluidic settings with a microcoaxial phaco tip statistically significantly decreases EPT. As only marginally more solution was used with the higher aspiration flow, occlusion must be accomplished more often with high than with low fluidics. Aspiration of the quadrants was therefore more efficient with high fluidic settings. The enhanced pump speed did not result in more tissue damage.

Posterior capsule opacification with the iMics1 NY-60 and AcrySof SN60WF 1-piece hydrophobic acrylic intraocular lenses: 3-year results of a randomized trial.

PURPOSE: To compare the intensity of posterior capsule opacification (PCO) 3 years after implantation of 2 different 1-piece foldable hydrophobic acrylic intraocular lenses (IOLs). DESIGN: Randomized, prospective, patient- and examiner-masked clinical trial with intraindividual comparison. METHODS: One hundred patients with bilateral age-related cataract (200 eyes) had standard cataract surgery with implantation of an iMics1 NY-60 IOL (Hoya Corp) in one eye and an AcrySof SN60WF IOL (Alcon Laboratories) in the other eye. Follow-up examinations were performed at 1 week and 3 years. Digital retroillumination images were obtained of each eye. The main outcome measure was PCO score (scale, 0 to 10) assessed subjectively at the slit lamp and objectively using automated image analysis software (Automated Quantification of After-Cataract) 3 years after surgery. RESULTS: The objective PCO score (mean ± standard deviation) was 3.0 ± 2.0 for the iMics1 NY-60 IOL and 1.9 ± 1.4 for the AcrySof SN60WF IOL (P < .001). Three years after surgery, 35.6% of patients underwent a neodymium:yttrium-aluminum-garnet capsulotomy in the iMics1 NY-60 eye and 13.7% underwent a capsulotomy in the AcrySof SN60WF eye (P = .001). There was no statistically significant difference in best-corrected visual acuity, rhexis-IOL overlap, capsular folds, or anterior capsule opacification. Glistening formations were found in no iMics1 NY-60 IOLs, but in 97% of the AcrySof SN60WF IOLs. CONCLUSIONS: Comparison of 2 sharp-edged single-piece IOLs of similar design and hydrophobic acrylic material indicated a statistically significant difference in PCO and neodymium:yttrium-aluminum-garnet capsulotomy rate 3 years after surgery.

Posterior capsule opacification and neodymium:YAG rates with 2 single-piece hydrophobic acrylic intraocular lenses: three-year results.

PURPOSE: To compare the incidence and intensity of posterior capsule opacification (PCO) between 2 similar 1-piece foldable hydrophobic acrylic intraocular lenses (IOLs) over 3 years. SETTING: Department of Ophthalmology, Medical University Vienna, Vienna, Austria. DESIGN: Randomized prospective patient- and examiner-masked clinical trial with intraindividual comparison. METHODS: Patients with bilateral age-related cataract had cataract surgery and implantation of a Tecnis ZCB00 continuous-optic-edge IOL in 1 eye and an Acrysof SA60AT interrupted-optic-edge IOL in the other eye. Postoperative examinations were performed at 6 months and 3 years. Digital retroillumination images were taken of each eye. The amount of PCO (score 0 to 10) was assessed subjectively at the slitlamp and objectively using automated image-analysis software. RESULTS: The study comprised 54 patients (108 eyes). The mean objective PCO score was 1.3 ± 1.7 (SD) for the continuous-optic-edge IOLs and 0.9 ± 1.3 for the interrupted-optic-edge IOLs (P=.10). Three years postoperatively, a neodymium:YAG (Nd:YAG) capsulotomy was performed in 26.1% of eyes with the continuous-optic-edge IOL and 21.7% with the interrupted-optic-edge IOL (P=.56). There was no significant difference in corrected distance visual acuity, capsulorhexis­IOL overlap, capsule folds, or anterior capsule opacification 3 years after surgery. CONCLUSIONS: Both IOLs had comparable PCO and Nd:YAG rates 3 years postoperatively. The optimized barrier function of the continuous-optic-edge IOL and the material properties of the interrupted-optic-edge IOL seemingly outbalanced the effect on lens epithelial cell migration and proliferation beneath the optic.

Imaging of the parafoveal capillary network and its integrity analysis using fractal dimension.

Using a spectral domain OCT system, equipped with a broadband Ti:sapphire laser, we imaged the human retina with 5 µm x 1.3 µm transverse and axial resolution at acquisition rate of 100 kHz. Such imaging speed significantly reduces motion artifacts. Combined with the ultra-high resolution, this allows observing microscopic retinal details with high axial definition without the help of adaptive optics. In this work we apply our system to image the parafoveal capillary network. We demonstrate how already on the intensity level the parafoveal capillaries can be segmented by a simple structural high pass filtering algorithm. This data is then used to quantitatively characterize the capillary network of healthy and diseased eyes. We propose to use the fractal dimension as index for capillary integrity of pathologic disorders.

Quantification of the therapeutic response of intraretinal, subretinal, and subpigment epithelial compartments in exudative AMD during anti-VEGF therapy.

PURPOSE: To analyze the functional and morphologic effects of different ranibizumab treatment regimens on retinal and subretinal as well as sub-RPE compartments in neovascular age-related macular degeneration (nAMD) using spectral-domain optical coherence tomography (SD-OCT) and manual segmentation software. METHODS: Twenty-seven eyes of 27 patients with nAMD were examined over a 12-month period. Two treatment arms received either monthly or quarterly administered intravitreal ranibizumab. Intraretinal, subretinal, and sub-RPE volume equivalents were delineated using manual segmentation software over a defined series of B-scans obtained by SD-OCT. The mean area in pixels was calculated for each compartment at each time interval. RESULTS: SD-OCT and manual segmentation allowed for exact identification of intraretinal, subretinal and sub-RPE compartments and their responses to different treatment regimens. The loading dose demonstrated a corresponding treatment effect on all anatomic parameters. In contrast to the sub-RPE compartment, intraretinal fluid accumulation and subretinal fluid accumulation (SRFA) demonstrated an immediate response to ranibizumab therapy. The overall plasticity of the morphologic response declined over time. In general, SRFA demonstrated greater sensitivity for therapeutic effects and was more frequently associated with recurrent disease. CONCLUSIONS: An exact quantification of fluid in different anatomic compartments based on SD-OCT imaging, using appropriate segmentation software systems, may be useful to determine optimal treatment and retreatment parameters and explains the lack of correlation of best-corrected visual acuity and conventional OCT values.

Performance of drusen detection by spectral-domain optical coherence tomography.

PURPOSE: To evaluate the performance of automated analyses integrated in three spectral-domain optical coherence tomography (SD-OCT) devices to identify drusen in eyes with early (i.e., nonatrophic and nonneovascular) age-related macular degeneration (AMD). METHODS: Twelve eyes of 12 AMD patients, classified as AREDS 2 and 3 and having a mean count of 113 drusen were examined with three clinical SD-OCT devices (Cirrus [Carl Zeiss Meditec, Dublin CA], 3DOCT-1000 [Topcon, Tokyo, Japan], and Spectralis [Heidelberg Engineering, GmbH, Heidelberg, Germany]) and five different scan patterns. After standard automated segmentation of the RPE was performed, every druse in each B-scan was identified and graded by two independent expert graders. Errors in the segmentation performance were classified as negligible, moderate, or severe. Correlations were based on the diameter and height of the druse and its automated segmentation. The overall drusen pattern identified by experts' detailed delineation was plotted with a custom-made computer program to compare automated to manual identification outcomes. RESULTS: A total of 1356 drusen were analyzed. The automated segmentation of the retinal pigment epithelium (RPE) by Cirrus made significantly fewer errors in detecting drusen than did the 3DOCT-1000 (P < 0.001). The Cirrus 200 × 200 scan pattern detected 30% of the drusen with negligible errors. Spectralis did not offer a true RPE segmentation. The drusen counts by expert graders were significantly higher in the scans than in the standard fundus photographs (P < 0.05). CONCLUSIONS: SD-OCT imaging proved an excellent performance in visualizing drusen-related RPE disease. However, the available automated segmentation algorithms showed distinct limitations to reliable identification of the amount of drusen, particularly smaller drusen, and the actual size.