{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,24]],"date-time":"2025-10-24T08:28:32Z","timestamp":1761294512995,"version":"build-2065373602"},"reference-count":37,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2022,8,26]],"date-time":"2022-08-26T00:00:00Z","timestamp":1661472000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Life"],"abstract":"<jats:p>Continuous wave (CW) and microsecond pulse (MP) laser irradiations were compared regarding cell damage and laser-induced temperature rise at retinal pigment epithelium (RPE). The RPE of porcine RPE-choroid-sclera explants was irradiated with a 577 nm laser in CW or MP mode (5% or 15% duty cycle (DC)) for 20 ms or 200 ms at an average laser power of 20\u201390 mW. Cell viability was investigated with calcein-AM staining. Optoacoustic (OA) technique was employed for temperature measurement during irradiation. For 200 ms irradiation, the dead cell area (DCA) increased linearly (\u22481600 \u00b5m2\/mW) up to the average power of 40 mW for all modes without significant difference. From 50 mW, the increase of DCA of MP-5% significantly dropped to 610 \u00b5m2\/mW (p &lt; 0.05), likely due to the detected microbubble formation. OA temperature measurement showed a monotonic temperature increase in CW mode and a stepwise increase in MP mode, but no significant difference in the average temperature increase at the same average power, consistent with the temperature modeling. In conclusion, there is no difference in the average temperature rise between CW and MP modes at the same average power regardless of DC. At lower DC, however, more caution is required regarding mechanical damage due to microbubble formation.<\/jats:p>","DOI":"10.3390\/life12091313","type":"journal-article","created":{"date-parts":[[2022,8,29]],"date-time":"2022-08-29T03:34:56Z","timestamp":1661744096000},"page":"1313","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":7,"title":["Temperature Increase and Damage Extent at Retinal Pigment Epithelium Compared between Continuous Wave and Micropulse Laser Application"],"prefix":"10.3390","volume":"12","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-1896-7634","authenticated-orcid":false,"given":"Yoko","family":"Miura","sequence":"first","affiliation":[{"name":"Institute of Biomedical Optics, University of L\u00fcbeck, 23562 L\u00fcbeck, Germany"},{"name":"Medical Laser Center L\u00fcbeck, 23562 L\u00fcbeck, Germany"},{"name":"Department of Ophthalmology, University of L\u00fcbeck, 23562 L\u00fcbeck, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Keiji","family":"Inagaki","sequence":"additional","affiliation":[{"name":"Inagaki Eye Clinic, Chiba 279-0011, Japan"},{"name":"Department of Ophthalmology, Faculty of Medicine, Juntendo University, Tokyo 113-8421, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Alessa","family":"Hutfilz","sequence":"additional","affiliation":[{"name":"Medical Laser Center L\u00fcbeck, 23562 L\u00fcbeck, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3496-5751","authenticated-orcid":false,"given":"Eric","family":"Seifert","sequence":"additional","affiliation":[{"name":"Medical Laser Center L\u00fcbeck, 23562 L\u00fcbeck, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Benedikt","family":"Schmarbeck","sequence":"additional","affiliation":[{"name":"Medical Laser Center L\u00fcbeck, 23562 L\u00fcbeck, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0022-2514","authenticated-orcid":false,"given":"Akira","family":"Murakami","sequence":"additional","affiliation":[{"name":"Department of Ophthalmology, Faculty of Medicine, Juntendo University, Tokyo 113-8421, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Kishiko","family":"Ohkoshi","sequence":"additional","affiliation":[{"name":"Department of Ophthalmology, Hiroo Hanezawa Internal Medicine and Ophthalmology Clinic, Tokyo 150-0012, Japan"},{"name":"Department of Ophthalmology, St. Luke\u2019s International Hospital, Tokyo 104-8560, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0445-8102","authenticated-orcid":false,"given":"Ralf","family":"Brinkmann","sequence":"additional","affiliation":[{"name":"Institute of Biomedical Optics, University of L\u00fcbeck, 23562 L\u00fcbeck, Germany"},{"name":"Medical Laser Center L\u00fcbeck, 23562 L\u00fcbeck, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2022,8,26]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"74","DOI":"10.1136\/bjo.2004.051540","article-title":"Subthreshold diode micropulse photocoagulation for the treatment of clinically significant diabetic macular oedema","volume":"89","author":"Luttrull","year":"2005","journal-title":"Br. 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