Blue light-filtering and violet light-filtering hydrophobic acrylic foldable intraocular lenses: Intraindividual comparison

Blue Light Filtration in Intraocular Lenses: Effects on Visual Function and Systemic Health

Blue light-filtering (BLF) intraocular lenses (IOLs) are designed to mimic the healthy natural adult crystalline lens. Studies that evaluated the relative merit of ultraviolet-only IOL design (ie, blocking wavelengths <400 nm) versus BLF IOL design (ie, filtering wavelengths ~400-475 nm in addition to blocking wavelengths <400 nm) on protection and function of the visual system suggest that neither design had a deleterious impact on visual acuity or contrast sensitivity. A BLF design may reduce some aspects of glare, such as veiling and photostress. BLF has been shown in many contexts to improve visual performance under conditions that are stressed by blue light, such as distance vision impaired by short-wave dominant haze. Furthermore, some data (mostly inferential) support the notion that BLF IOLs reduce actinic stress. Biomimetic BLF IOLs represent a conservative approach to IOL design that provides no harm for visual acuity, contrast sensitivity, or color vision while improving vision under certain circumstances (eg, glare).

Visual Outcomes, Quality of Vision, Patient Satisfaction and Spectacle Independence After Bilateral Implantation of the Synergy™ Intraocular Lens

Purpose

To evaluate vision, visual quality, patient satisfaction and spectacle independence after bilateral implantation of the TECNIS Synergy™ intraocular lens.

Setting

Two clinical practices in the USA.

Design

Ambispective unmasked non-randomized clinical trial.

Methods

Patients with a history of uneventful bilateral femtosecond laser assisted cataract surgery with the study IOL implanted, targeted for emmetropia, at least 3 months prior to the study visit were enrolled. Monocular and binocular visual acuity (VA) were measured at distance, intermediate and near, along with binocular mesopic VA. Low contrast binocular VA and reading speed in mesopic and photopic conditions were also measured. Patient satisfaction, spectacle independence, visual symptoms, and functional vision questionnaires were completed.

Results

Results from 52 subjects were available for analysis. Mean binocular unaided visual acuity was ~0.1 logMAR (20/20) from distance to 33 cm, with 81% of subjects having 0.2 logMAR (20/25) vision or better at all test distances and 92% reporting never needing glasses at any distance. Average reading speed at 40 cm was only 10 words/minute slower in dim light (p = 0.03). Mesopic and low contrast acuity appeared good. Halos were the most frequent and bothersome visual disturbances, with the greatest effect on driving at night. Eighty-eight percent of subjects reported being "completely" or "mostly" satisfied with their overall unaided vision.

Conclusion

This hybrid technology IOL provided a range of binocular visual acuity from distance to 33 cm and good functional vision, even in dim light. Patients should be advised of the likelihood of visual disturbances, particularly halos.

Comparison of visual performance between bifocal and extended-depth-of-focus intraocular lenses

We compared the visual performance of a bifocal intraocular lens (IOL) (ZMB00) and an extended-depth-of-focus (EDOF) IOL (ZXR00V) by evaluating postoperative parameters at 10 weeks after the last surgery in cataract patients who underwent bilateral ZMB00 or ZXR00V implantation between 2011 and 2020. The right and left lenses were implanted within 3 months of each other. The study enrolled 1536 eyes of 768 patients; the ZMB00 group comprised 1326 eyes of 663 patients (age: 67.0 ± 7.8 years; female/male, 518/145), and the ZXR00V group comprised 210 eyes of 105 patients (age: 67.8 ± 6.9 years; female/male, 39/66). A linear mixed-effects model using data for both eyes, with strict adjustments for sex, age, subjective refraction spherical equivalent, subjective refraction cylinder, corneal astigmatism, axial length, corneal higher-order aberrations and pupil diameter, ensured statistical validity. Uncorrected near visual acuity, corrected near visual acuity, and near spectacle independence were significantly better in the ZMB00 group (p<0.00068, Wald test) than in the ZXR00V group. Contrast sensitivity (visual angle of the test target: 4.0°/2.5°/1.6°/1.0°/0.7°) and contrast sensitivity with glare (4.0°/2.5°/1.6°/1.0°/0.7°) were significantly better in the ZXR00V group (p<0.00068, Wald test) than in the ZMB00 group. Uncorrected intermediate visual acuity, contrast sensitivity with glare (6.3°), and 25-item National Eye Institute Visual Function Questionnaire (VFQ-25) scores for General Vision were slightly but significantly better in the ZXR00V group than in the ZMB00 group (p<0.05, Wald test). At high-performance levels, the two IOL groups had different characteristics regarding various visual performance parameters.

The Incidence of Optic Cracks or Fractures During a Foldable AcrySof or Acriva BB Acrylic Monofocal Intraocular Lens Implantation via the Manual Monarch Injector System With the Cartridge in Phacoemulsification Surgery

PURPOSE

To evaluate the incidence of optic cracks and/or fractures during foldable acrylic intraocular lens (IOL) implantation via the manual Monarch delivery system with the cartridge and to determine factors that help to avoid such complications.

METHODS

Small-incision phacoemulsification surgery was performed in 702 eyes with visually significant cataract formation. A foldable acrylic soft IOL (AcrySof^â MA60BM/MA30BA, Alcon, Fort Worth, TX, USA) or a single-piece acrylic soft IOL (Acriva BB^â, VSY Biotechnology, Amsterdam, The Netherlands) was inserted in all eyes using a cartridge and viscoelastic agents (sodium hyaluronate, Healon^®, Advanced Medical Optics, Santa Ana, CA, USA).

RESULTS

Postoperative central, paracentral, or peripheral optic cracks or fractures were encountered in a total of six of 702 eyes (0.85%). Four of six lenses (0.57%) had optic cracks within the IOL substance, whereas two of 702 cases (0.28%) had full-thickness IOL fractures in the substance in multiple locations. Three of the four lenses with optic cracks were noted to be handled by tying forceps during the cartridge insertion, and one of them was the complication of holding forceps. Two IOLs with full-thickness optic fractures were encountered during the insertion of the IOLs in the capsular bag as a result of direct trauma to the lens optic by the plunger of the injector system overriding the lens optic during cartridge passage. None of the patients suffered from glare or other visual disturbances postoperatively, and, therefore, none of the six eyes required lens replacement.

CONCLUSION

The unintentional extensive pressure effect of the forceps during the holding process of the IOL or the direct trauma to the lens optic by the plunger of injector systems may cause optic cracks or fractures. Physicians should continue to monitor the eyes postoperatively regularly and must determine the benefits and risks to be derived from lens replacement, if such patients complain of significant glare, image degradation, and visual disturbances. We recommend the use of preloaded lenses, which have their own delivery systems and cartridges, to minimize the risk of such complications.

Visual Performance of a Violet-Filtering Intraocular Lens versus a Blue-Filtering Intraocular Lens of New/Old Manufacturing Processes

This article compares the visual performance of a violet light-filtering colored lens (ZCB00V) and blue light-filtering intraocular lens (IOL; SN60WF) before and after modifying the manufacturing process for glistening suppression. In this retrospective study, conducted at Saneikai Tsukazaki Hospital, Himeji, Japan, a consecutive sample of 8943 eyes of 5119 patients were included and implanted with blue-filtering IOLs before and after modifying the manufacturing process (SN60WF-J (1318 eyes) and SN60WF-Q,A (1418 eyes), respectively), noncolored UV-cut IOLs (ZCB00 (1418 eyes)), and ZCB00V (3717 eyes). For each patient, the corrected distance visual acuity (CDVA) at 3 months postoperative (3MCDVA) and the area under log contrast sensitivity function (AULCSF) were measured. The 3MCDVA was -0.076 ± 0.1, -0.11 ± 0.13, -0.10 ± 0.17, and -0.11 ± 0.13, for SN60WF-J, SN60WF-Q,A, ZCB00, and ZCB00V, respectively. The SN60WF-J group revealed significant differences as compared to the other three groups (all p < 0.05). The mesopic AULCSF was 2.59 ± 0.20, 2.68 ± 0.19, -2.69 ± 0.18, and 2.76 ± 0.19, respectively, whereas the photopic AULSCF was 2.63 ± 0.23, 2.76 ± 0.25, -2.77 ± 0.25, and 2.88 ± 0.25. The SN60WF-J and ZCB00V groups exhibited significant differences as compared to the other three groups, whereas no significant differences were noted between the SN60WF-Q,A and the ZCB00 groups (all p < 0.05). The violet-filtering lens offers higher visual acuity and contrast sensitivity than the clear and blue-filtering lens. It was also found that the above functions were improved by modifying the manufacturing process.

Comparative spectrophotometer analysis of ultraviolet-light filtering, blue light-filtering and violet-light filtering intraocular lenses

Purpose

To compare the light transmittance property of 7 currently used intraocular lens models (IOLs) by spectrophotometer data.

Materials and methods

Light-transmission spectra of 7 IOL models were assessed with a spectrophotometer. The transmittance properties were analyzed in 1 nm units from 350 nm wavelength to 800 nm.

Results

Three UV filtering IOL models (ZCB00, XC1-SP, AT LISA 809M) showed nearly full transmittance of the light from 400 to 500 nm, while steeply attenuating light with shorter wavelengths in various degrees. Three blue-light filtering IOLs (yellow-tinted IOLs; XY1, SN60WF, TNFT00) showed a slow-sloped increase of light transmission between 400 to 500nm. Among the three, XY1 showed different degree of inclination, showing a steeper slope than SN60WF and TNFT00. The violet-light filtering IOL (ZFR00V) showed a rapid increase of the transmission at around 435 nm wavelength, which is similar to UV filtering IOLs.

Conclusions

The seven different IOLs measured showed different characteristics of light transmission depending on the properties of each material and color. Blue-light filtering IOLs tend to blocked a wide range of wavelength up to 500nm, but rather were not effective at the range of 400 to 430nm. Violet-light filtering IOL showed advantages in filtering the high-energy wavelength, around 430nm, having a potential risk to retina and allowing the transmission of useful blue and green wavelength which is necessary for a better scotopic contrast sensitivity.

Intraocular Lenses: Overview of Designs, Materials, and Pathophysiologic Features

This article provides an overview of intraocular lenses (IOLs) currently used in cataract surgery. Aspects presented include design features related to IOL construction and sites of fixation; optic, filter, and haptic materials; as well as pathophysiologic features of uveal biocompatibility, capsular biocompatibility, and postoperative IOL opacification. This overview also includes supplementary (add-on; piggyback) lenses implanted in eyes that are already pseudophakic and considerations on IOLs used in the pediatric population. Different IOLs are made available to surgeons each year, including lenses with increasingly complex design characteristics owing to advancements in manufacturing and surgical techniques.