Effect of subthreshold nanosecond laser on retinal structure and function in intermediate age-related macular degeneration.

BACKGROUND: Subthreshold nanosecond laser (SNL) treatment has been studied as a potential intervention in intermediate age-related macular degeneration (iAMD). This study investigated the effect of 100 SNL treatment spots on retinal structure and function. METHODS: A prospective single-arm interventional pilot study. SNL treatment was delivered as 100 spots around the retinal vascular arcades of the study eye (worst visual acuity) in a single session in subjects with iAMD. Multimodal retinal imaging and dark-adapted chromatic perimetry were performed at baseline and at 0.5, 3, 6 and 12 months post treatment. Post treatment changes in best corrected visual acuity (BCVA), retinal thickness, relative ellipsoid zone reflectivity (rEZR) and rod-mediated functional parameters were compared to baseline. RESULTS: Twenty-one subjects with iAMD were recruited. SNL treatment was associated with an increase in retinal thickness (p = 0.008) and decrease in rEZR (p < 0.001) at 2 weeks post laser. Recovery of retinal thickness and rEZR was observed at the 3-month post laser visit. A gradual improvement in BCVA was observed after laser treatment. The mean change in BCVA between baseline and 12-month visit was +1.9 ± 3.3 letters for the SNL treated eyes, compared to -0.4 ± 3.0 letters for the fellow eyes (p = 0.027). Rod-mediated function improved at 3 months post laser (p < 0.001) and returned to the baseline levels at 12 months post treatment. CONCLUSIONS: A single treatment with 100 SNL spots causes a short-term change in retinal structure and improvement in retinal function that are apparent at 3 months post treatment.

Multi-focal electro-retinogram response following sub-threshold nano-second laser intervention in age-related macular degeneration.

IMPORTANCE: The effect of sub-threshold nano-second laser (SNL) treatment on retinal function remains unknown. BACKGROUND: SNL treatment has been studied as a potential intervention in intermediate age-related macular degeneration (iAMD). This study investigated the longitudinal effect of SNL treatment on retinal function. DESIGN: This was a sub-study of the LEAD trial; a 36-month, multi-centre, randomized and sham-controlled trial. PARTICIPANTS: Subjects with iAMD. METHODS: Eligible participants were assigned randomly to receive SNL or sham treatment to the study eye at 6-monthly visits. Multi-focal electro-retinography (mfERG) was performed at each study visit from a study site. The mfERG responses were grouped into three regions (central, middle and outer rings) and compared between the SNL and sham group. MAIN OUTCOME MEASURES: mfERG P1 response amplitude and implicit time. RESULTS: Data were collected from 50 subjects (26 in the SNL group, 24 in the sham group). At baseline, the P1 amplitudes of both the study eyes and the fellow eyes were similar between the groups at all rings. In the sham group, the P1 amplitude gradually decreased over time (P < .05). In the SNL group, there was an improvement in P1 amplitude which became statistically significant at the 36-month visit, detected in both the treated and fellow eyes at the central (P = .005) and middle ring (P = .007) but not at the outer ring (P = .070). No difference in P1 implicit time detected between the groups (P > .05). CONCLUSIONS AND RELEVANCE: SNL treatment improved electro-physiological function. mfERG could be useful for monitoring AMD progression and evaluating the efficacy of SNL treatment.

Doyne honeycomb retinal dystrophy - functional improvement following subthreshold nanopulse laser treatment: a case report.

BACKGROUND: Based on phenotypic similarities between age-related macular degeneration and the autosomal disorder Doyne honeycomb retinal dystrophy, we report on a single nanolaser treatment of a patient with genotype Doyne honeycomb retinal dystrophy confirmation and evidence of disease progression over 12 months. The case study is the first report of short-term results of subthreshold nanolaser treatment in a patient with Doyne honeycomb retinal dystrophy. CASE PRESENTATION: A 43-year-old Caucasian man with moderate loss of visual acuity in his left eye (20/40) and normal visual acuity in his right eye (20/20), with clinical Doyne honeycomb retinal dystrophy diagnosis and genetic confirmation of the common heterozygous mutation (EFEMP1) by genetic testing, underwent nanopulse subthreshold laser treatment in his left eye. A safety examination, carried out 7 days after treatment, and clinical follow-up, conducted 60 days following laser treatment, showed improvement of visual acuity from baseline by two letters and a subjective improvement of blurring. While no apparent morphological changes were found on fundoscopy, increased autofluorescence in the treated eye was observed on imaging. In addition, 2 months after nanopulse subthreshold laser treatment, rod-mediated and cone-mediated full-field electroretinography b-wave amplitudes showed an increase from baseline in both the treated eye (300%) and untreated eye (50%). At 2 months after nanopulse subthreshold laser treatment, multifocal electroretinograms showed improvement. Acuity and full-field electroretinography improvement persisted at 6-month follow-up. CONCLUSIONS: Sustained improvements in retinal function on electroretinography persisted in both eyes 6 months after treatment, suggesting an enhancement of phototransduction and retinoid recycling induced by nanopulse subthreshold laser treatment. The functional improvement observed in the untreated eye is hypothesized to arise from an increased expression and release of metalloproteinases that circulate systemically.

Modus Operandi of Protective and Anti-icing Mechanisms Underlying the Design of Longstanding Outdoor Icephobic Coatings.

Atmospheric icing has become a global concern due to hazardous consequences of ice accretion on air, land, and sea transport and infrastructure. Icephobic surfaces due to their physicochemical properties facilitate a decrease in ice and snow accumulation under outdoor conditions. However, a serious problem of most superhydrophobic surfaces described in the literature is poor operational durability under harsh corrosive and abrasive loads characteristic of atmospheric operation. Here, we elucidate main surface phenomena determining the anti-icing behavior and show experimentally how different mechanisms contribute to long-term durability. For comprehensive exploitation of those mechanisms, we have applied a recently proposed strategy based on fine-tuning of both laser processing and protocols of deposition of the fluorooxysilanes onto the nanotextured surface. Prolonged outdoor tests evidence that a developed strategy for modification of materials on the nanolevel allows overcoming the main drawbacks of icephobic coatings reported so far and results in resistance to destroying atmospheric impacts.