Investigations into localized re‐treatment of the retina with a 3‐nanosecond laser

Chidlow, Glyn; Plunkett, Malcolm; Casson, Robert J.; Wood, John

doi:10.1002/lsm.22506

Cited by 11 publications

(16 citation statements)

References 43 publications

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“…These new cells retile over the laser region, theoretically rejuvenating the RPE with new ''younger'' RPE cells in these areas. 23,24,29 The results of the current study are consistent with these previous findings. At 5 hours after subthreshold laser, flat mount labeling with phalloidin, a high-affinity F-actin probe that labels RPE cell membranes, showed RPE cells were ablated.…”

Section: Effects Of Nanosecond Laser Treatment On the Rpe And Bruch'ssupporting

confidence: 83%

“…In addition, no evidence of other abnormal vessel labeling within the retina was apparent. This finding is consistent with the work of Chidlow et al 23 who have shown histologically that at 7 days after nanosecond pulsed laser treatment, dark-agouti rats do not have vascular leakage or abnormal choroidal vessels even when a suprathreshold, high-energy treatment is used. We extended on this initial finding, showing that not only at 7 days, but also at 3 months, there is no histologic evidence of CNV in eyes treated with a clinically relevant laser dose (0.065 mJ).…”

Section: The Nanosecond Laser Does Not Induce Angiogenesis In Mice Evsupporting

confidence: 82%

“…22,23,[25][26][27]29 When used at an energy setting similar to that used in the clinical trials for AMD, nanosecond pulsed laser treatment has been found to preserve retinal integrity in humans and mice. [28][29][30] In the present study, using both a clinically equivalent, subthreshold laser dose (0.065 mJ) and an in vivo fundus-OCT imaging method, we showed for the first time, to our knowledge, that retinal structure directly below the sites of laser treatment is normal.…”

Section: Neuronal Integrity Is Preserved Directly Under Sites Treatedmentioning

confidence: 99%

“…Specifically, in vivo studies in mice and rats, and ex vivo studies using human RPE/choroidal explants, suggest that the laser energy is selectively absorbed by the melanin pigment within the RPE, causing localized cell loss. 23,24,29 It has been suggested that within 1 week, the otherwise nonmitotic RPE reenters the cell cycle at the edges of the laser site, dividing to create new cells. These new cells retile over the laser region, theoretically rejuvenating the RPE with new ''younger'' RPE cells in these areas.…”

Section: Effects Of Nanosecond Laser Treatment On the Rpe And Bruch'smentioning

confidence: 99%

“…The 3-ns pulsed laser has similar features to conventional 532-nm CW photocoagulation lasers, but the pulse duration selectively modulates pigmented tissues while minimizing thermal damage to the delicate apposing retinal neurons. 22,23 Previously, the acute effects of the nanosecond pulsed laser have been investigated on human RPE/choroidal explants 24 and in in vivo rat models 22,23,[25][26][27] at an energy setting similar to that used in the clinical trials. The results of these studies show that the nanosecond pulsed laser induced significantly less collateral damage than the CW laser.…”

mentioning

confidence: 99%

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Nanosecond Laser Treatment for Age-Related Macular Degeneration Does Not Induce Focal Vision Loss or New Vessel Growth in the Retina

Vessey

Jobling

et al. 2018

Invest. Ophthalmol. Vis. Sci.

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PURPOSE. Subthreshold, nanosecond pulsed laser treatment shows promise as a treatment for age-related macular degeneration (AMD); however, the safety profile needs to be robustly examined. The aim of this study was to investigate the effects of laser treatment in humans and mice. METHODS.Patients with AMD were treated with nanosecond pulsed laser at subthreshold (no visible retinal effect) energy doses (0.15-0.45 mJ) and retinal sensitivity was assessed with microperimetry. Adult C57BL6J mice were treated at subthreshold (0.065 mJ) and suprathreshold (photoreceptor loss, 0.5 mJ) energy settings. The retinal and vascular responses were analyzed by fundus imaging, histologic assessment, and quantitative PCR.RESULTS. Microperimetry analysis showed laser treatment had no effect on retinal sensitivity under treated areas in patients 6 months to 7 years after treatment. In mice, subthreshold laser treatment induced RPE loss at 5 hours, and by 7 days the RPE had retiled. Fundus imaging showed reduced RPE pigmentation but no change in retinal thickness up to 3 months. Electron microscopy revealed changes in melanosomes in the RPE, but Bruch's membrane was intact across the laser regions. Histologic analysis showed normal vasculature and no neovascularization. Suprathreshold laser treatment did not induce changes in angiogenic genes associated with neovascularization. Instead pigment epithelium-derived factor, an antiangiogenic factor, was upregulated.CONCLUSIONS. In humans, low-energy, nanosecond pulsed laser treatment is not damaging to local retinal sensitivity. In mice, treatment does not damage Bruch's membrane or induce neovascularization, highlighting a reduced side effect profile of this nanosecond laser when used in a subthreshold manner.

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Section: Effects Of Nanosecond Laser Treatment On the Rpe And Bruch'ssupporting

confidence: 83%

Section: The Nanosecond Laser Does Not Induce Angiogenesis In Mice Evsupporting

confidence: 82%

Section: Neuronal Integrity Is Preserved Directly Under Sites Treatedmentioning

confidence: 99%

Section: Effects Of Nanosecond Laser Treatment On the Rpe And Bruch'smentioning

confidence: 99%

mentioning

confidence: 99%

See 3 more Smart Citations

Nanosecond Laser Treatment for Age-Related Macular Degeneration Does Not Induce Focal Vision Loss or New Vessel Growth in the Retina

Vessey

Jobling

et al. 2018

Invest. Ophthalmol. Vis. Sci.

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Association of Long-term Ambient Black Carbon Exposure and Oxidative Stress Allelic Variants With Intraocular Pressure in Older Men

et al. 2019

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IMPORTANCE Elevated intraocular pressure is a major risk factor for glaucoma, a leading cause of irreversible blindness worldwide. Environmental air pollution has been suggested as a potential contributor to elevated intraocular pressure; however, no studies have demonstrated such an association to date. OBJECTIVE To investigate the association of long-term ambient black carbon exposure with intraocular pressure in community-dwelling older adults. DESIGN, SETTING, AND PARTICIPANTS This population-based analysis, conducted from October 18, 2017, through March 22, 2018, used data from the all-male, New England-based Normative Aging Study of the US Department of Veterans Affairs. The analysis included 419 older men with a total of 911 follow-up study visits between January 1, 2000, and December 30, 2011. Intraocular pressure was measured by Goldmann applanation tonometry during the study visits. Validated spatiotemporal models were used to generate 1-year black carbon exposure levels at the addresses of the participants. MAIN OUTCOMES AND MEASURES An independently developed genetic score approach was used to calculate allelic risk scores for 3 pathways associated with black carbon toxicity: endothelial function, oxidative stress, and metal processing. The associations among black carbon exposure, allelic risk scores, and intraocular pressure were explored using linear mixed-effects models. RESULTS All 419 participants were men with a mean (SD) age of 75.3 (6.9) years. The mean (SD) 1-year black carbon exposure was 0.51 (0.18) μg/m 3 , and the mean (SD) intraocular pressure for the left eye was 14.1 (2.8) mm Hg and for the right eye was 14.1 (3.0) mm Hg. Of the 911 visits, 520 (57.1%) had a high endothelial function allelic risk score, 644 (70.7%) had a high metal-processing allelic risk score, and 623 (68.4%) had a high oxidative stress allelic risk score. In fully adjusted linear mixed-effects models, the association of black carbon with intraocular pressure was greater in individuals with a high oxidative stress allelic score (β = 0.36; 95% CI, 0.003-0.73) compared with individuals with a low score (β = −0.35; 95% CI, −0.86 to 0.15). CONCLUSIONS AND RELEVANCE Ambient black carbon exposure may be a risk factor for increased intraocular pressure in individuals susceptible to other biological oxidative stressors. If additional studies confirm these results, monitoring ambient black carbon exposure and physiological oxidative stress may prevent the development and progression of intraocular pressure-related disease.

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Advancements in Imaging and Therapeutic Options for Dry Age-Related Macular Degeneration and Geographic Atrophy

Servillo,

Sacconi,

Oldoni

et al. 2024

Ophthalmol Ther

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Age-related macular degeneration (AMD) is a leading cause of vision loss in the elderly, with dry AMD (d-AMD) leading to geographic atrophy (GA) and significant visual impairment. Multimodal imaging plays a crucial role in d-AMD diagnosis and management, allowing for detailed classification of patient phenotypes and aiding in treatment planning and prognosis determination. Treatment approaches for d-AMD have recently witnessed profound change with the development of specific drugs targeting the complement cascade, with the first anticomplement agents recently approved for GA treatment. Additionally, emerging strategies such as gene therapy and laser treatments may offer potential benefits, though further research is needed to fully establish their efficacy. However, the lack of effective therapies capable of restoring damaged retinal cells remains a major challenge. In the future, genetic treatments aimed at preventing the progression of d-AMD may emerge as a powerful approach. Currently, however, their development is still in the early stages.

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Investigations into localized re‐treatment of the retina with a 3‐nanosecond laser

Cited by 11 publications

References 43 publications

Nanosecond Laser Treatment for Age-Related Macular Degeneration Does Not Induce Focal Vision Loss or New Vessel Growth in the Retina

Nanosecond Laser Treatment for Age-Related Macular Degeneration Does Not Induce Focal Vision Loss or New Vessel Growth in the Retina

Association of Long-term Ambient Black Carbon Exposure and Oxidative Stress Allelic Variants With Intraocular Pressure in Older Men

Advancements in Imaging and Therapeutic Options for Dry Age-Related Macular Degeneration and Geographic Atrophy

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