Miyake-Apple View Research Articles

Unintended placement of intraocular lens haptics in the sulcus and its association with posterior capsular opacification in pseudophakic post-mortem eyes

ObjectiveTo assess the prevalence of unintended placement of intraocular lens (IOL) haptics in the sulcus and its association with posterior capsular opacification (PCO). DesignCross-sectional study. Participants428 post-mortem pseudophakic human eyes. MethodsEyes were obtained from the Lions Gift of Sight and imaged in Miyake-Apple view (MAV). IOL haptic placement (bag–bag, bag–sulcus, sulcus–sulcus) was determined from the MAV images. IOL-capsular bag complexes were extracted and analyzed via Automated Detector Opacification Software to quantify PCO and Soemmering's Ring (SR). SR distribution was categorized as focal, diffuse, or none. Mean differences in PCO and SR between haptic groups were assessed via Welch's t-test. Odds ratios were used to compare the risk of SR distribution patterns between both haptic groups. Sex, clinical history (diabetes, smoking, hypertension, glaucoma, cancer, age-related macular degeneration [AMD], hypercholesterolemia, cardiovascular disease), and IOL model and specifications were collected. Results20 eyes (4.67%) had unintended sulcus placement of haptics. Mean PCO (p = 0.0367) and SR (p = 0.0414) were significantly higher in sulcus eyes. Sulcus eyes were significantly more at risk of focal SR distribution (OR 8.715; p < 0.0001) and significantly less at risk of diffuse SR distribution (OR 0.168; p = .0007). Sulcus eyes had significantly higher frequencies of glaucoma (p < 0.0001) and AMD (p = 0.0023) on clinical history. ConclusionsThis study demonstrates that unintended sulcus placement of IOL haptics may be associated with an increased risk of PCO and SR formation. This study offers clinical signs of sulcus haptic placement that may prompt physicians to seek earlier appropriate intervention.

Objective analysis of capsulorrhexis factors and posterior capsular opacification in 420 postmortem eyes

ObjectiveTo evaluate the capsulorrhexis structure in postmortem eyes and determine factors associated with posterior capsular opacification (PCO). DesignExperimental study. ParticipantsPostmortem pseudophakic human eyes (n = 420). MethodsPostmortem eyes were obtained and examined. Photographs were taken of the eyes in Miyake-Apple view and of the extracted lens-capsule complexes. PCO and Soemmering's ring (SR) were quantified using automated detector opacification software as factors of intensity and area. Miyake-Apple views and ImageJ were used to assess capsulorrhexis diameter, area of anterior capsule-optic overlap, length of the shortest anterior capsular leaflet, and area and angle of capsulorrhexis-optic nonoverlap. Linear regression analysis and Welch's t test were used to determine the relationship of these factors with PCO and SR. All analyses were repeated in sample groups specific to the 5 most common intraocular lens models. ResultsCapsule-optic overlap was positively correlated with PCO (P < 0.0001) and SR (P = 0.0016). Capsulorrhexis diameter was negatively correlated with PCO (P < 0.0001) and SR (P = 0.014). Leaflet length was positively correlated with PCO (P = 0.009). Area and angle of capsulorrhexis-optic nonoverlap were not correlated with PCO or SR. Slopes and coefficients of determination were relatively low for all significant results. ConclusionsThe pathogenesis of PCO development after cataract surgery is multifactorial. This study shows that with modern operating technology, capsulorrhexis factors have at best a modest influence on PCO formation. Factors such as time from surgery to death and intraoperative techniques such as laser capsule polishing, posterior capsule vacuuming, and cortical cleanup are likely to play a more significant role.

Clinical and anatomic correlates of objectively measured zonular dehiscence in 427 postmortem pseudophakic eyes

ObjectifLa présente étude vise à mesurer de manière objective le degré de déhiscence zonulaire dans des yeux de donneurs cadavériques et à évaluer les corrélations cliniques et anatomiques. NatureÉtude transversale. MatérielQuatre cent vingt-sept yeux pseudophaques de donneurs cadavériques humains. MéthodesLes yeux provenaient de la banque d'yeux Lions Gift of Sight. Les photographies des yeux au microscope consistaient en une vue postérieure de segment antérieur (Miyake–Apple view); on a eu recours au logiciel ImageJ pour réaliser l'analyse de la zone visée afin de mesurer l'aire, la circonférence et le diamètre du sac capsulaire, de l'anneau ciliaire et du capsulorhexis. Les paramètres cliniques et anatomiques ont été évalués grâce à une analyse de régression linéaire simple et à une analyse de la variance à un facteur s'accompagnant d'un test de Bonferroni. On s'est servi de 2 paramètres de substitution pour mesurer la déhiscence zonulaire : le rapport de l'aire de la capsule sur l'aire de l'anneau ciliaire (CCR, pour capsule area over ciliary ring area ratio) et la décentration de la capsule par rapport à l'anneau ciliaire (CCD, pour capsule-ciliary ring decentration). Un CCR faible et une CCD élevée correspondent à une déhiscence zonulaire plus prononcée. RésultatsOn a noté une corrélation inverse significative entre le CCR et un capsulorhexis de plus petite taille (p = 0,012), une lentille intraoculaire de plus faible puissance (p < 0,00001), un âge moins avancé lors du décès (p = 0,00002) et un délai plus long entre l'apparition des cataractes et le décès (p = 0,00786). Le CCR était en outre significativement plus faible en présence de glaucome (p = 0,0291). Par ailleurs, la CCD était en corrélation significative avec un délai plus long entre l'apparition des cataractes et le décès (p = 0,000864), une plus grande aire de l'anneau ciliaire (p = 0,001), une opacification plus prononcée de la capsule postérieure (p = 0,0234) et une opacité plus prononcée de l'anneau de Soemmering (p = 0,0003). Enfin, on a enregistré significativement plus de décentration dans les yeux d'hommes que dans les yeux de femmes (p = 0,00852). ConclusionsLe CCR et la CCD constituent de nouvelles façons de mesurer la déhiscence zonulaire dans des yeux de donneurs cadavériques et permettent de mettre au jour de nombreuses corrélations intéressantes. Un élargissement de l'aire de l'anneau ciliaire pourrait être associé à une déhiscence zonulaire dans des yeux pseudophaques et peut vraisemblablement servir de variable de substitution quantifiable in vivo.

New Miyake-Apple View system using a nasal endoscope.

To evaluate images and videos behind the anterior segment of cataract surgery with the porcine eye using a new Miyake-Apple View with a nasal endoscope. Sugiura Eye Clinic, Fuji, Shizuoka, Japan. Laboratory study. A hole was made in a commercially available wooden desk and the nasal endoscope was fixed under the desk. A tunnel for passing the probe of the nasal endoscope was opened on a Styrofoam human-faced base, and the probe was passed through. A 3 mm × 3 mm incision was made behind the globe, and a nasal endoscope probe was inserted to observe the posterior anterior segment of the eye. The posterior part of the anterior segment of the eye could be clearly observed, and each procedure (hydrodissection, phacoemulsification, irrigation and aspiration, and insertion and fixation of intraocular lens [IOL]) in normal cataract surgery could be observed from the posterior. Lighting could be improved. The conventional Miyake-Apple View required a large-scale custom-made device, which was expensive and could not be taken easily, and required to cut the globe and a technique to fix it to the glass plate. However, this method made it easy to prepare for shooting, and the equipment was inexpensive. Furthermore, it had the great advantage of not having to cut the globe. Since the integrity of the globe was maintained, normal cataract surgery could be reproduced and dynamic observation from the back became possible. It was useful for practicing cataract surgery and examining the fixed state of new IOLs.

An Experimental Laboratory Study Using the Miyake-Apple Posterior View Technique to Investigate the Dynamics Between Capsular Bags and Different IOL Models.

To evaluate the dynamics between capsular bags and different intraocular lens (IOL) models in human cadaver eyes using the Miyake-Apple posterior view technique. In an in vitro laboratory study, human cadaver eyes were prepared according to the Miyake-Apple posterior view technique. Five IOLs from each of the six groups (Avansee 1P [Simonvision], Avansee 3P [Simonvision], CT Lucia [Carl Zeiss Meditec], Acrysof [Alcon Laboratories, Inc], RayOne [Rayner], and CT Asphina [Carl Zeiss Meditec]) were implanted into capsular bags with different diameters. The empty capsular bag diameter and capsular bag diameter with an IOL in it were evaluated based on the Miyake-Apple view pictures. Posterior capsule striae were observed and compared between groups. The arc of contact between IOLs and the capsular equator was noted. Correlations between the empty capsular bag diameter and the capsular bag diameter with IOL, as well as between the empty capsular bag diameter and the arc of contact, were examined. With the Avansee 3P as a reference, the area deviation of the haptics of IOL models with looped haptics was compared. The capsular bag diameter with IOL inside and the arc of contact were proportional to the empty capsular bag diameter. The RayOne, Avansee 3P, and CT Lucia showed a longer arc of contact. Posterior capsule striae were observed in the Avansee 1P (1, 20%), Avansee 3P (5, 100%), Acrysof (1, 20%), and RayOne (2, 40%). Areas of deviation were 0.38 mm2 (Avansee 1P), 0.24 mm2 (CT Lucia), 0.34 mm2 (Acrysof), and 0.31 mm2 (RayOne), respectively. Different IOL models showed varied characteristics in terms of capsular bag fitting and arc of contact. Understanding these dynamics is critical to optimizing postoperative outcomes. [J Refract Surg. 2022;38(10):654-660.].

Comparison of a new IOL injector system against 3 standard IOL injector systems with different incision sizes: Miyake-Apple view experimental laboratory study.

To compare 1 new intraocular lens (IOL) injector system against 3 standard injector systems in porcine eyes. David J Apple Center for Vision Research, Department of Ophthalmology, University Hospital Heidelberg, Heidelberg, Germany. In vitro laboratory study. In 70 porcine eyes, +20.0 diopter IOLs were implanted with the following systems: multiSert, UltraSert, iTec, and RayOne, that is, S1.8 (incision size: 1.8 mm), S2.0 (2.0 mm), S2.2P (2.2 mm, push mode), S2.2S (2.2 mm, screw mode), U2.2 (2.2 mm), iT2.2 (2.2 mm), and R2.0 (2.0 mm). Corneal incision sizes were measured before and after implantation with an incision gauge set. Ease of use was evaluated using a Likert scale. IOL delivery time and performance were determined based on Miyake-Apple view videos. Of the 70 eyes studied, the incision enlargements were 0.36 ± 0.08 mm (S1.8), 0.15 ± 0.07 mm (S2.0), 0.17 ± 0.12 mm (S2.2P), 0.28 ± 0.10 mm (S2.2S), 0.32 ± 0.09 mm (U2.2), 0.30 ± 0.08 mm (iT2.2), and 0.35 ± 0.11 mm (R2.0). Total scores of ease of use were 23.00 (S1.8), 25.00 (S2.0), 29.00 (S2.2P), 26.00 (S2.2S), 26.00 (U2.2), 25.00 (iT2.2), and 24.00 (R2.0). As for the mean delivery time, iT2.2 took the longest time (13.20 ± 3.29 seconds), whereas S2.2S took the shortest time (4.50 ± 0.71 seconds). Optic-haptic adhesion was observed in S1.8 (4, 40%), S2.2P (2, 20%), U2.2 (5, 50%), and iT2.2 (5, 50%). Injector S, with the appropriate incision size and implantation method, could achieve better results regarding incision enlargement, ease of use, delivery time, and performance than other injector systems. There was an indirect relationship between incision size and inadvertent events.

Long-term uveal and capsular biocompatibility of a new fluid-filled, modular accommodating intraocular lens.

To evaluate long-term uveal and capsular biocompatibility of a new fluid-filled modular accommodating intraocular lens (IOL) consisting of base and fluid lenses. John A. Moran Eye Center, University of Utah, Salt Lake City, UT, USA. Experimental study. Bilateral phacoemulsification was performed on 8 rabbits; 1 eye received the test IOL (Juvene) and the other a hydrophobic acrylic control IOL (SA60AT). Slitlamp examinations were performed at postoperative weeks 1 and 4, and at months 2, 3, and 6. The rabbits were killed humanely at 6 months. After gross examination from the Miyake-Apple view, IOLs were removed for implant cytology. All globes were then processed for histopathologic examination. Uveal biocompatibility was similar between test and control IOLs up to 6 months postoperatively. Anterior capsule opacification appeared absent in the test group, and posterior capsule opacification (PCO) was significantly less in comparison with the control group throughout the study. At 6 months, central PCO was scored as 0.12 ± 0.23 with test IOLs and as 4.0 ± 0 with control IOLs (P < .0001, 2-tailed t test: paired 2-sample for means). Histopathologic examination confirmed the relative lack of capsular opacification in test eyes in comparison to controls and the absence of toxicity in any eye. Six weeks in the rabbit model corresponds to approximately 2 years in the human eye for PCO. In this model, the Juvene IOL maintained an open and expanded capsular bag, preventing overall capsular bag opacification while retaining excellent uveal and capsular biocompatibility.

Explantation/exchange of the components of a new fluid-filled, modular, accommodating IOL.

To evaluate the ease of replacement and capsular stability of a new fluid-filled, modular, accommodating intraocular lens (IOL) system composed of a monofocal base lens with a fluid lens clipped inside of it. John A. Moran Eye Center, University of Utah, Salt Lake City, Utah, USA. Experimental study. Five New Zealand rabbits underwent bilateral phacoemulsification with implantation of the test lens (Juvene, LensGen, Inc.) in both eyes (4 rabbits), or a control IOL in 1 eye (AcrySof, Alcon Laboratories, Inc.) and the test IOL in the other (1 rabbit). At 2 weeks, the 4 rabbits with bilateral Juvene IOLs had the clipped-in fluid lens exchanged for a new fluid lens in 1 eye, and the base and fluid lenses exchanged for a control lens in the contralateral eye. Slitlamp examinations were performed weekly for 4 weeks. The globes were enucleated and evaluated with ultrasound biomicroscopy, grossly from the posterior Miyake-Apple view, and histopathologically. Explantation/exchange of the fluid lens was considered straightforward by the surgeon. Explantation of the base lens (4) was also safely performed, albeit more demanding, without any signs of damage to the capsular bag under clinical, ultrasound biomicroscopy, and pathological examination in the exchanged eyes. Less capsular bag opacification was observed with the Juvene lens system. Explantation/exchange of the fluid lens component, or both fluid and base lenses, of this new lens system can be safely accomplished if necessary, because of its modular design and the relative lack of postoperative capsular bag opacification associated with it.

Uveal and capsular biocompatibility of a new hydrophobic acrylic microincision intraocular lens

To evaluate uveal biocompatibility and capsular bag opacification of a new hydrophobic acrylic microincision intraocular lens (IOL) in comparison with a commercially available 1-piece hydrophobic acrylic IOL. John A. Moran Eye Center, University of Utah, Salt Lake City, Utah, USA. Experimental study. Eight New Zealand rabbits underwent bilateral phacoemulsification and implantation of the preloaded Nanex multiSert IOL in one eye and a commercially available preloaded lens (AcrySof IQ in UltraSert, model AU00T0) in the contralateral eye. A slitlamp examination was performed weekly for 4 weeks. The rabbits were then killed humanely and their globes enucleated. Capsular bag opacification was assessed from the Miyake-Apple view, and the eyes were subjected to histopathologic evaluation. Postoperative inflammatory reactions were similar between the test and control eyes in the 8 New Zealand rabbits. The mean postmortem central posterior capsule opacification (PCO) was 0.93 ± 0.73 in the test group and 1.19 ± 0.53 in the control group. The mean postmortem peripheral PCO was 1.75 ± 0.92 in the test group and 2.06 ± 0.77 in the control group. Central and peripheral PCO scores were not statistically different between the test and control groups (P = .41 and P = .35, respectively, 2-tailed t test: paired 2-sample for means). A new 1-piece hydrophobic acrylic microincision IOL incorporating an ultraviolet-ozone treatment on the posterior surface performed similarly to a commercially available 1-piece hydrophobic acrylic IOL in terms of uveal and capsular biocompatibility in the rabbit model. To our knowledge, this is the first hydrophobic acrylic microincision IOL to demonstrate similar PCO performance when compared with a conventional, commercially available IOL.

Posterior capsule opacification prevention by an intraocular lens incorporating a micropatterned membrane on the posterior surface.

To evaluate posterior capsule opacification (PCO) with a new hydrophobic acrylic intraocular lens (IOL) featuring a new micropatterned membrane, in comparison with a commercially available 1-piece hydrophobic acrylic IOL. John A. Moran Eye Center, University of Utah, Salt Lake City, Utah, USA. Experimental study. Twelve New Zealand rabbits had bilateral phacoemulsification and implantation of a ClearSight unpatterned IOL (Group 1), a ClearSight Sharklet-patterned IOL (Group 2), or a control, commercially available IOL (Group 3) (8 IOLs in each group). Slit-lamp examination was performed weekly for 4 weeks. The rabbits were then killed humanely, and their globes enucleated. Capsular bag opacification was assessed from the Miyake-Apple view, and the eyes underwent histopathology. The mean postmortem central PCO was 1.87 ± 1.35 in Group 1, 1.06 ± 1.23 in Group 2, and 3.14 ± 0.89 in Group 3. Peripheral PCO was 2.18 ± 1.36 in Group 1, 1.5 ± 1.03 in Group 2, and 3.57 ± 0.53 in Group 3. When comparing central and peripheral PCO between Groups 1 and 3, the difference was not statistically significant, but it was statistically significant between Groups 2 and 3 (P = .003 and P = .0003, t test with Bonferroni correction). Unique discontinuous features comprising the micropattern allow for focal adhesions to be precisely guided and therefore controlling cell migration. The patterned membrane incorporated on the posterior surface of the IOL significantly reduced capsular bag opacification compared with a commercially available control IOL.

Quantification of residual ophthalmic viscosurgical device after irrigation/aspiration in experimental cataract surgery in vitro

To determine the distribution and quantity of ophthalmic viscosurgical device (OVD) retained in the lens capsular bag after irrigation/aspiration (I/A) in experimental cataract surgery. Department of Ophthalmology, Kashiwa Hospital, Jikei University School of Medicine, Japan. Experimental study. Fifteen freshly enucleated porcine eyes were used. Sodium hyaluronate 1.0% (Healon) was mixed with a fixed concentration of silica nanoparticles encapsulating fluorescein isothiocyanate (labeled OVD), and it was injected separately into the capsular bag and injector cartridge for intraocular lens (IOL) insertion. After a 3-piece IOL (YA-60BBR) or a 1-piece IOL (iSert 255) was implanted within the capsular bag, OVD was removed by thorough I/A. Eyes that were injected with the labeled OVD into the capsular bag without IOL insertion were used as controls. The distribution of residual OVD in the capsular bag was observed under ultraviolet irradiation using Miyake-Apple view. Then, the excised capsular bag was dissolved in hydrogen fluoride, and silica concentration was measured quantitatively by elemental analysis. The quantity of residual OVD in the capsular bag was 243.1μg±1.3 (SD) in the 3-piece IOL-implanted group, 383.8±11.1μg in the 1-piece IOL-implanted group, and 99.0±1.3μg in the control group. In the 1-piece IOL-implanted eyes, OVD in the form of clumps tended to remain near the center of the optic on the posterior side, and the quantity of residual OVD was significantly greater than in 3-piece IOL-implanted eyes (P<.05). The quantity of residual OVD after I/A could be determined indirectly using labeled OVD, and the quantity was significantly greater in 1-piece IOL-implanted eyes than in 3-piece IOL-implanted eyes.

Influence of irrigation dynamic pressure-assisted hydrodissection on intraocular pressure and the posterior chamber-anterior hyaloid membrane barrier during cataract surgery.

To evaluate the effects of irrigation dynamic pressure-assisted hydrodissection (irrigation-hydro: iH) on intraocular pressure (IOP) and the posterior chamber-anterior hyaloid membrane (PC-AHM) barrier in porcine eyes. Experimental. In Experiment 1, IOP was recorded while irrigating the anterior chamber (AC), during iH, and during phacoemulsification and aspiration in 20 porcine eyes using bottle heights of 50, 70, and 90cm. Under the same conditions, IOP was recorded during conventional manual cortical cleaving hydrodissection (manual hydro: mH) in 20 porcine eyes. In Experiment 2, after iH, ACs were perfused for 5 seconds with balanced salt solution containing 1.0-μm fluorescein beads in 20 porcine eyes using bottle heights of 70, 118, and 169cm. PC-AHM barrier staining grade was evaluated by the Miyake-Apple view. iH proved successful in all cases. In Experiment 1, IOP during iH was relatively stable and peak IOP was below the baseline bottle height-dependent pressure. No eyes showed a peak IOP > 75mmHg during iH, but 8 eyes showed a peak IOP > 75mmHg during mH. In Experiment 2, neither AHT nor ruptured capsules were observed at any bottle height. Unlike mH, IOP during iH was relatively stable without any high peak IOP. Thus, iH offers a simple technique for reducing peak IOP and avoiding disturbance of the PC-AHM barrier.

In vivo evaluation of a new hydrophobic acrylic intraocular lens in the rabbit model

To evaluate the uveal and capsular biocompatibility as well as positioning stability of a new hydrophobic acrylic intraocular lens (IOL) invivo in the rabbit model and compare it with a commercially available IOL. John A Moran Eye Center, University of Utah, Salt Lake City, Utah, USA. Experimental study. Fifteen New Zealand rabbits had the new test IOL(Clareon CNA0T0) implanted in one eye and a control IOL (Acrysof SN60WF) implanted in the contralateral eye. The testIOL is manufactured from a new hydrophobic acrylic material incorporating ultraviolet blocker and blue light filter. Its design is based on the control IOL's platform. The rabbits were followed up with weekly slitlamp evaluations, which assessed inflammatory reactions as well as capsular bag opacification. Anterior chamber depth was measured at 1 and 4weeks post-implantation (high-frequency ultrasound). After 4weeks, the rabbits were killed humanely and the eyes were enucleated. The anterior segment was evaluated from the posterior or Miyake-Apple view, and was then processed for complete histopathology. There were no statistically significant differences between test and control eyes in terms of postoperative inflammation and capsular biocompatibility, including posterior capsule opacification (P=.34, paired t test), and anterior capsule opacification (P=.53, paired t test), as observed during clinical and pathological evaluation. Invivo axial positioning for the test IOL was comparable to the control IOL and stable over time (P=.531 versus P=.788). The new IOL showed biocompatibility and stability comparable to the control IOL.

Removing Subjective Post-Mortem Grading from Posterior Capsular Opacification: A New Automated Detector Opacification Software, ADOS

ABSTRACTPurpose/aim: Posterior capsular opacification (PCO) is the leading complication following cataract surgery. However, PCO grading methods vary between studies and rely on subjective scoring methods; hence, they are prone to error. Therefore, software that reduces subjectivity and enhances reproducibility is needed. The aim of the study was to evaluate the reproducibility and objectivity of a novel automated custom-designed PCO detection software.Materials and Methods: In total, 165 fixed eyes with intraocular lenses were sectioned to obtain a Miyake Apple view (MAV) image. The capsular bag (CB) with the in situ IOL was removed and imaged using the Olympus DSX110 stereoscope. Central, peripheral, and Soemmering’s ring area (SRA) and intensity (SRI) were graded by two ophthalmologists using a scale of 0–4. Software was developed to detect PCO, and these values were correlated with subjective scoring.Results: Intra-observer agreement for MAV and CB images ranged from poor to moderate, with very good agreement for SRI (k = 0.88, 0.86, respectively). Agreement between graders was fair to good (k = 0.31–0.77). Miyake Apple view and capsular bag images showed good correlation; central PCO showed the least correlation for both evaluators (k = 0.29, 0.72). Subjective average grading versus software correlation demonstrated very good correlation for intensity and good for area (r = 0.85, 0.61). Reproducibility of the methodology resulted in good to very good correlation.Conclusions: Software correlates with previous scoring methods and is a reliable and reproducible system. Moreover, the capsular bag view, as opposed to the Miyake Apple view, allows visualization of the capsular bag directly and avoids overlapping structures (vitreous, cornea) that may interfere with proper PCO quantification.

Further Enhancement of Intraocular Open-Capsule Devices for Prevention of Posterior Capsule Opacification.

PurposeWe improve the intraocular open-capsule devices (IOCD) for the prevention of posterior capsule opacification (PCO).MethodsA total of 45 New Zealand rabbit eyes were divided into six similar groups after crystalline lens evacuation. Each group was implanted with a hydrophilic intraocular lens (IOL) and a hydrophilic IOCD of different designs. In the first experiment (Part A), a square design ring with and without large apertures was compared to a round design ring without apertures. In the second experiment (Part B), a square design ring with large apertures was compared to square design IOCDs with small apertures of high and low density. PCO and Soemmering's ring were evaluated clinically, by the Miyake Apple view, and histologically. The results were compared to a control group of eyes implanted with a hydrophilic IOL only.ResultsAll devices showed significant prevention of PCO and Soemmering's ring compared to the control group. Part A: the square design with apertures had the lowest level of peripheral lens epithelial cells proliferation (protrusions). Part B: modifying the size and density of the apertures had no influence on those protrusions.ConclusionsThe IOCD significantly reduced the rate of PCO and its precursor, Soemmering's ring. The rings with the square edges and apertures produced the best results. The study was underpowered to determine the influence of the apertures design.Translational RelevanceThe IOCD has the potential to prevent up to 80% of the PCO cases; the most common complication after cataract surgery. The design of the ring is important for its success.

Long-term uveal and capsular biocompatibility of a novel modular intraocular lens system.

We evaluated the long-term biocompatibility and safety of a new modular posterior chamber intraocular lens (IOL) system in rabbit eyes. Seven New Zealand rabbits underwent bilateral phacoemulsification with placement of the modular IOL in OD and a control IOL (SA60AT) in OS. Slit-lamp examinations were performed at postoperative weeks 1, 2, 3, 4, 6 and 8 and months 3 and 6. All rabbits were then sacrificed and eyes enucleated. The eyes were examined grossly from the Miyake-Apple view. Selected IOLs were explanted and underwent surface staining for implant cytology. All globes were then sectioned and processed for histopathological examination. The modular IOL remained stable in all seven rabbits through the entire follow-up period. Biocompatibility was better than the control lens at six months postoperatively, on account of less extensive synechiae formation as assessed by slit-lamp examination. At the six-week examination, posterior capsule opacification (PCO) was significantly better in the test group (scored as 1.71±0.8 versus 3.28±0.48 in the control group, p=0.0008). On gross examination with the Miyake-Apple view, Soemmering's ring formation was significantly better in the test group, (5.14±1.57 versus 10.85±1.95 in the control group, p=0.002). Previous studies showed that explantation/exchange of the modular system optic was safer and easier than with a standard IOL. The new modular IOL system has demonstrated better long-term biocompatibility compared to the control lens at six months postoperatively in the rabbit model.

Biocompatibility of intraocular lens power adjustment using a femtosecond laser in a rabbit model

To evaluate the biocompatibility (uveal and capsular) of intraocular lens (IOL) power adjustment by a femtosecond laser obtained through increased hydrophilicity of targeted areas within the optic, creating the ability to build a refractive-index shaping lens within an existing IOL. John A. Moran Eye Center, University of Utah, Salt Lake City, Utah, USA. Experimental study. Six rabbits had phacoemulsification with bilateral implantation of a commercially available hydrophobic acrylic IOL. The postoperative power adjustment was performed 2weeks after implantation in 1 eye of each rabbit. The animalswere followed clinically for an additional 2weeks and then killedhumanely. Their globes were enucleated and bisected coronally just anterior to the equator for gross examination from the Miyake-Apple view to assess capsular bagopacification. After IOL explantation for power measurements, the globes were sectioned and processed for standard histopathology. Slitlamp examinations performed after the laser treatments showed the formation of small gas bubbles behind the lenses that disappeared within a few hours. No postoperative inflammation or toxicity was observed in the treated eyes, and postoperative outcomes and histopathological examination results were similar to those in untreated eyes. The power measurements showed that the change in power obtained was consistent and within ±0.1 diopter of the target. Consistent and precise power changes can be induced in the optic of commercially available IOLs invivo by using a femtosecond laser to create a refractive-index shaping lens. The laser treatment of the IOLs was biocompatible.

Evaluation of long-term biocompatibility and capsular bag opacification with a new silicone–polyimide plate-type intraocular lens in the rabbit model

To evaluate the long-term biocompatibility and safety of the new SC9 intraocular lens (IOL) after implantation in rabbit eyes, in accordance with the requirements of the International Organization for Standardization 11979-5, Annex G:2006(E). John A. Moran Eye Center, University of Utah, Salt Lake City, Utah, USA. Experimental study. Bilateral phacoemulsification was performed on 9 New Zealand white rabbits; 1 eye received the test IOL and the contralateral eye received a commercially available plate-type silicone control IOL (AA4204VL). Two rabbits were humanely killed at 2months and the remaining at 6months. After gross examination of the eyes from the posterior Miyake-Apple view, select IOLs were explanted and had surface staining for implant cytology. All globes were then sectioned and processed for complete histopathologic examination. Overall uveal biocompatibility was similar between the test IOLs and control IOLs throughout the study. The mean posterior capsule opacification at 6months was 0.8±0.27 (SD) in the test group and 4.0±0 in the control group (P=.001, t test: paired 2-sample for means). The mean posterior synechiae formation at 6months was 1.28±1.25 in the test group and 2.71±0.75 in the control group (P=.01). A histopathologic examination confirmed the relative lack of capsule opacification in the study eyes compared with the control eyes and the absence of untoward inflammatory reaction or toxicity in all eyes. The new IOL maintained an open capsular bag secondary to its design, which appeared to prevent overall capsular bag opacification and retain uveal and capsule biocompatibility. None of the authors has a financial or proprietary interest in any material or method mentioned.

Evaluation of stability and capsular bag opacification with a foldable intraocular lens coupled with a protective membrane in the rabbit model

To evaluate the stability and capsular bag opacification of a smooth or a patterned silicone protective membrane implanted in the bag with secondary placement of an intraocular lens (IOL). John A. Moran Eye Center, University of Utah, Salt Lake City, Utah, USA. Experimental study. Twelve New Zealand rabbits had bilateral implantation of a protective membrane and an IOL or an IOL alone. Three groups of 8 eyes each received the IOL and the smooth protective membrane, the IOL and the patterned membrane, or the IOL alone. Slitlamp examination was performed weekly for 4 weeks. The rabbits were then humanely killed and their globes enucleated. Capsular bag opacification was scored based on the Miyake-Apple view, and the eyes underwent histopathology. At 4 weeks, the mean central posterior capsule opacification (PCO) score was 0.28 ± 0.32 (SD) in all eyes with a protective membrane and 2.08 ± 1.28 in eyes with the IOL alone (P < .00001, Student t test). Peripheral PCO and Soemmerring ring formation were also significantly less in eyes with the protective membrane. Histopathologically, the posterior capsules were relatively clear in most IOLs with the protective membrane. The smooth and patterned protective membranes showed a significant difference in overall capsular bag opacification formation compared with the IOLs without the membrane. The circular geometry of the protective membrane led to expansion of the capsular bag and appeared to prevent capsular bag opacification. Further studies are warranted to assess whether the pattern on the device's posterior surface further enhances this effect. No author has a financial or proprietary interest in any material or method mentioned.

Evaluation of stability and capsular bag opacification of a new foldable adjustable intraocular lens.

Incorrect lens power remains one of the most common reasons for intraocular lens explantation/exchange. We evaluated stability and effect on capsular bag opacification of a new foldable modular lens system, with a base component and an optic component in rabbit eyes. Bilateral phacoemulsification was performed on six rabbits; one eye received the test lens (Harmoni Modular Lens, ClarVista Medical), whereas the other received a single-piece hydrophobic acrylic control lens (SA60AT, Alcon). Slit-lamp examinations were performed at postoperative weeks 1, 2, 3, 4 and 6. All rabbits were sacrificed at week 6. After enucleation, the eyes were examined grossly from the Miyake-Apple view. Following, all globes were sectioned and processed for histopathological examination. The modular lens was stable in all six rabbits. Uveal biocompatibility was similar to or better in the test eyes when compared with control eyes up to 6 weeks postoperatively. Overall, capsular bag opacification was found to be significantly lower in the test eyes when compared with control eyes. At the 6-week gross examination, central posterior capsule opacification was scored as 0.58 ± 0.73 in the test group, and as 3.00 ± 1.26 in the control group (paired two samples for means t-test; two-tail P = 0.005). The Harmoni Modular system remains stable within the capsular bag after implantation. Due to the design of the base component featuring long loops, along with peripheral anterior and posterior square edges, the lens appeared to prevent overall capsular bag opacification in the rabbit model.