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Evaluation of Visual Comfort and Mental Effort Under Different Light

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Evaluation of Visual Comfort and Mental Effort Under Different Light Klinische Studie Evaluation of Visual Comfort and Mental Effort Under Different Light Conditions for Ultraviolet-Absorbing and Additional Blue-Filtering Intraocular Lenses for Cataract Surgery Visueller Komfort und mentale Anstrengung bei unterschiedlichem Umgebungslicht nach Kataraktoperation mit ultraviolett- versus zusätzlich blaufiltrierenden Intraokularlinsen Authors Alexandra Steinemann 1, Vivien Bromundt 2, Sarah L. Chellappa 3, Sylvia Frey4, Christina Schmidt 5, Torsten Schlote 6, David Goldblum1,ChristianCajochen4 Affiliations ABSTRACT 1 Augenklinik, Universitätsspital Basel, Basel, Switzerland Patients and Methods Patients with an ultraviolet blocking 2 Chronobiologie, Inselspital Universitätsspital Bern, Bern, lens (UV) (n = 5) or blue filter lens (BB) (n = 8) after intraocular Switzerland lens (IOL) replacement for cataract and age-adjusted controls 3 Division of Sleep Medicine, Harvard Medical School, (AACs) (n = 16) underwent a balanced crossover within-sub- Boston, Massachusetts, United States ject design. After 1.5 h of dark adaptation, they were exposed 4 Chronobiologie, Universitätsspital Basel, Basel, Switzerland to polychromatic light at 6500 K (blue-enriched) and 2500 K 5 GIGA-Research, Cyclotron Research Centre/In Vivo and 3000 K (non-blue-enriched) for 2 hours in the evening. Imaging Unit, Université de Liège Département des Visual comfort and mental effort were repeatedly assessed Sciences de la Vie, Liège, Belgium by the Visual Analogue Scale (0–100) and the Visual Comfort 6 Ophthalmology, Tagesklinik Ambimed, Basel, Switzerland and Mental Effort Rating Scale (0–100) for each light condi- tion. The results were compared using mixed model analysis. Key words Results The mean (± SD) age for AAC and patients with UV or cataract, visual comfort, mental effort, intraocular lens, blue BBwas69.8±6.2y,70.8±4y,and63.6±5.6y,respectively. filter Irrespective of the light condition, patients with UV and BB felt mentally more tired during the experiments compared to Schlüsselwörter AACs (F = 6.15, p = 0.003). However, patients with BB were Katarakt, visual comfort, mental effort, Intraokularlinse, mentally more motivated to perform the exercises compared Blaufilter to patients with UV and AACs (F = 8.1, p < 0.001). Patients Downloaded by: Universität Basel. Copyrighted material. with BB perceived ambient light as less glary (F = 4.71, received 11.10.2018 p = 0.01) than patients with UV. Blue ambient light was felt accepted 27.11.2018 less intensely in patients with BB (F = 2.51, p = 0.042) com- Bibliography pared to those with UV and the AACs. DOI https://doi.org/10.1055/a-0810-0302 Conclusion Lens replacement in older cataract patients may Published online 7.1.2019 | Klin Monatsbl Augenheilkd 2019; increase visual comfort and minimize mental effort. While 236: 398–404 © Georg Thieme Verlag KG Stuttgart · subtle, the magnitude of these effects may depend on the New York | ISSN 0023-2165 type of intraocular lens. BB intraocular lenses may have poten- tial benefits, as ambient light is perceived as having less glare Correspondence and less visual tension. Prof. David Goldblum Universitätsspital Basel, Augenklinik ZUSAMMENFASSUNG Mittlere Strasse 91, 4031 Basel, Switzerland Hintergrund Bei schwierigen Lichtverhältnissen ist der visu- Phone:+41612658686,Fax:+41612658743 elle Komfort beeinträchtigt und die mentale Anstrengung [email protected] beim Sehen erhöht; besonders gilt dies für Kataraktpatienten. Unterschiedliche Intraokularlinsen stehen bei der Katarakt- operation zur Verfügung: die regulären ultraviolettblockie- 398 Steinemann A et al. Evaluation of Visual … Klin Monatsbl Augenheilkd 2019; 236: 398–404 renden (UV) und Intraokularlinsen mit zusätzlichem Blaufilter Ergebnisse Das mittlere Alter von AAC und Patienten mit UV (BB). Die intrinsischen photosensitiven retinalen Zellen sind oder BB war 69,8 ± 6,2, 70,8 ± 4, 63,6 ± 5,6 Jahre. Unabhängig hochsensitiv für blaues Licht. Blaues Licht beeinflusst daher vom Umgebungslicht empfanden Patienten mit UV und BB die visuelle Funktion. Das Ziel der Studie war der Vergleich die Tests als ermüdender im Vergleich zu den Patienten mit des visuellen Komforts und der mentalen Anstrengung bei Pa- AAC (F = 6,15, p = 0,003). Die Patienten mit BB waren moti- tienten mit UV gegenüber solchen mit BB im Vergleich zu vierter, die Tests durchzuführen, bei blau angereichertem einer altersadaptierten Kontrollgruppe (AAC). Umgebungslicht im Vergleich zu den Patienten mit UV und Patienten und Methoden Patienten mit AAC (n = 16) sowie AAC (F = 8,1, p < 0,001). Patienten mit BB haben die Umge- UV (n = 5) und BB (n = 8) nach Kataraktoperation wurden in bungslichter als weniger blendend wahrgenommen als die eine ausgewogene Cross-over-Studie eingeschlossen. Nach Patienten mit UV (F = 4,71, p = 0,01). Blau angereichertes 1,5 h Dunkeladaption erfolgte im Labor die Exposition für 2 h Umgebungslicht wurde als weniger nervös machend wahr- bei blau angereichertem polychromatischem Umgebungs- genommen bei Patienten mit BB (F = 2,51, p = 0,042) vergli- licht bei 6500 K (Kandula), nicht blau angereichertem Licht chen mit Patienten mit UV und AAC. bei 2500 bzw. 3000 K. Für jedes Umgebungslicht wurde bei Schlussfolgerung Obwohl der visuelle Komfort und die jeder Testserie erneut der Fragebogen zum visuellen Komfort mentale Anstrengung zwischen BB und UV in den meisten und der mentalen Anstrengung (Visual Comfort und Mental Aspekten vergleichbar ist, unterscheiden sich die Patienten- Effort Rating Scale) ausgefüllt. Die Antworten wurden jeweils gruppen in ausgewählten Aspekten. BB sind möglicherweise auf einer visuellen Analogskala von 0–100 eingetragen. Die vorteilhaft, da das Umgebungslicht als weniger blendend statische Auswertung erfolgte mittels Mixed-Model-Analyse. empfunden wird und weniger mentale Anspannung für das Sehenerforderlichist. Introduction contrast vision. Although the benefits and side effects of blue filters are ultimately not clarified, it is assumed that blue filters Typically, the transparent crystalline lens develops bilateral hard- compared to UV blocking reduce damage or progression of age- ening and clouding during normal aging. This compromises visual related macular degeneration [9]. On the other side, the blue por- acuity and contrast sensitivity as well as glare sensation. The prev- tion of the visible light spectrum is beneficial for regulating hu- alence of age-related cataract affects approximately 75% of the man sleep-wake cycles and circadian rhythms, particularly in older population above 85 years old [1]. people. Thus, it is not clear whether a BB may negatively impact The common therapy of advanced cataract consists of the re- visual quality, scotopic vision, and circadian sleep-wake regulation moval of the accumulated yellow chromophore lens and implan- in older cataract patients. tation of an artificial intraocular lens (IOL). Different kinds of lens While targeted interventions for restoring optimal spectral replacements exist, such as monofocal, aspheric, or multifocal. transmittance include the implantation of artificial IOLs during Early IOL replacements did not filter a specific light wavelength cataract surgery, it remains to be fully established whether the until Ham et al. postulated retinal damage due to overexposure beneficial effects of cataract IOLs translate to changes in visual of ultraviolet light [2]. Ratnayake et al. investigated the mecha- comfort and mental effort during light exposure. Here, it was in- Downloaded by: Universität Basel. Copyrighted material. nisms of phototoxity and subsequent retinal damage caused by vestigated whether IOL replacement [blue blocking (BB) or UV blue light [3]. It is, however, known that the cornea and the natu- only blocking, (UV)] in older cataract patients improves visual ral lens absorb wavelengths below 300 nm. Wavelengths between comfort and mental effort, as compared to age-matched healthy 300 and 400 nm are absorbed by the iris, but pass the pupillary older adults. aperture and the lens [4]. Thus, to optimize the function of aged lenses, IOL replacements with ultraviolet filtering and additional blue filters were constructed [5]. Patients and Methods The adult crystalline lens blocks ultraviolet radiation about The protocol and questionnaires were approved by the ethical 300–400 nm [6]. The age-related change of the natural crystalline committee of Northwest and Central Switzerland and were in ac- lens leads to a progressive reduction of the transmission in the cordance with the Declaration of Helsinki. All patients gave their blue range of the visible light [7]. The ultraviolet blocking lens informed consent. (UV) reduces the blue-light irradiance by 60% compared to Patients were recruited at the eye clinic of the University Hos- aphakic eyes. The blue filter lens (BB) blocks an additional 17– pital Basel, Switzerland, and the Ambimed Basel Clinic, Switzer- 56% compared to the UV, depending on the type of implanted land. Patients aged between 55–80 years of age, with age-related IOL and the diopter of the IOL [5]. The blue light transmission rate cataracts requiring bilateral cataract surgery and a minimum of was down or below 25% in a 75-year-old and was around 70% in a +18 diopter and a maximum of +26 diopters for the IOL were in- 53-year-old human crystalline lens, which corresponds to the cluded. Further inclusion criteria were a body mass index between transmission rate of the BB [8]. 18 and 28 kg/m2, and stable medication for the past 2 months be- After IOL replacement for a cataract,
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