July 2019

El Rassi E, Adappa ND, Battaglia P, Castelnuovo P, Dallan I, Freitag SK, Gardner PA, Lenzi R, Lubbe D, Metson R, Moe KS, Muscatello L, Mustak H, Nogueira JF, Palmer JN, Prepageran N, Ramakirshnan VR, Sacks R, Snyderman CH, Stefko TS, Turri-Zanoni M, Wang EW, Zhou B, Bleier BS. Development of the international orbital Cavernous Hemangioma Exclusively Endonasal Resection (CHEER) staging system. Int Forum Allergy Rhinol 2019;9(7):804-812.Abstract
BACKGROUND: Orbital cavernous hemangiomas (OCH) are the most common adult orbital tumor and represent an ideal index lesion for endonasal orbital tumor surgery. In order to standardize outcomes reporting, an anatomic-based staging system was developed. METHODS: An international, multidisciplinary panel of 23 experts in orbital tumor surgery was formed. A modified Delphi method was used to develop the cavernous hemangioma exclusively endonasal resection (CHEER) staging system with a total of 2 rounds being completed. RESULTS: Tumors medial to a plane along the long axis of the optic nerve may be considered amenable for an exclusively endonasal resection. In select cases, tumors may extend inferolaterally if the tumor remains below a plane from the contralateral naris through the long axis of the optic nerve (ie, plane of resectability [POR]). This definition reached consensus with 91.3% of panelists in agreement. Five stages were designed based on increasing technical resection difficulty and potential for morbidity. Stages were based on the relationship of the tumor to the extraocular muscles, the inferomedial muscular trunk of the ophthalmic artery (IMT), and orbital foramina. Staging by anatomic location also reached consensus with 87.0% of panelists in agreement. Size was not included in the staging system due to the lack of agreement on the contribution of size to resection difficulty. CONCLUSION: Endoscopic orbital tumor surgery is a nascent field with a growing, yet heterogeneous, body of literature. The CHEER staging system is designed to facilitate international, high-quality, standardized studies establishing the safety, efficacy, and outcomes of endonasal resection of OCH.
Yokomizo H, Maeda Y, Park K, Clermont AC, Hernandez SL, Fickweiler W, Li Q, Wang C-H, Paniagua SM, Simao F, Ishikado A, Sun B, Wu I-H, Katagiri S, Pober DM, Tinsley LJ, Avery RL, Feener EP, Kern TS, Keenan HA, Aiello LP, Sun JK, King GL. Retinol binding protein 3 is increased in the retina of patients with diabetes resistant to diabetic retinopathy. Sci Transl Med 2019;11(499)Abstract
The Joslin Medalist Study characterized people affected with type 1 diabetes for 50 years or longer. More than 35% of these individuals exhibit no to mild diabetic retinopathy (DR), independent of glycemic control, suggesting the presence of endogenous protective factors against DR in a subpopulation of patients. Proteomic analysis of retina and vitreous identified retinol binding protein 3 (RBP3), a retinol transport protein secreted mainly by the photoreceptors, as elevated in Medalist patients protected from advanced DR. Mass spectrometry and protein expression analysis identified an inverse association between vitreous RBP3 concentration and DR severity. Intravitreal injection and photoreceptor-specific overexpression of RBP3 in rodents inhibited the detrimental effects of vascular endothelial growth factor (VEGF). Mechanistically, our results showed that recombinant RBP3 exerted the therapeutic effects by binding and inhibiting VEGF receptor tyrosine phosphorylation. In addition, by binding to glucose transporter 1 (GLUT1) and decreasing glucose uptake, RBP3 blocked the detrimental effects of hyperglycemia in inducing inflammatory cytokines in retinal endothelial and Müller cells. Elevated expression of photoreceptor-secreted RBP3 may have a role in protection against the progression of DR due to hyperglycemia by inhibiting glucose uptake via GLUT1 and decreasing the expression of inflammatory cytokines and VEGF.
Sangaré LO, Yang N, Konstantinou EK, Lu D, Mukhopadhyay D, Young LH, Saeij JPJ. GRA15 Activates the NF-κB Pathway through Interactions with TNF Receptor-Associated Factors. MBio 2019;10(4)Abstract
The protozoan parasite secretes proteins from specialized organelles, the rhoptries, and dense granules, which are involved in the modulation of host cell processes. Dense granule protein GRA15 activates the nuclear factor kappa B (NF-κB) pathway, which plays an important role in cell death, innate immunity, and inflammation. Exactly how GRA15 activates the NF-κB pathway is unknown. Here we show that GRA15 interacts with tumor necrosis factor receptor-associated factors (TRAFs), which are adaptor proteins functioning upstream of the NF-κB transcription factor. We identified several TRAF binding sites in the GRA15 amino acid sequence and showed that these are involved in NF-κB activation. Furthermore, a TRAF2 knockout cell line has impaired GRA15-mediated NF-κB activation. Thus, we determined the mechanism for GRA15-dependent NF-κB activation. The parasite can cause birth defects and severe disease in immunosuppressed patients. Strain differences in pathogenicity exist, and these differences are due to polymorphic effector proteins that secretes into the host cell to coopt host cell functions. The effector protein GRA15 of some strains activates the nuclear factor kappa B (NF-κB) pathway, which plays an important role in cell death, innate immunity, and inflammation. We show that GRA15 interacts with TNF receptor-associated factors (TRAFs), which are adaptor proteins functioning upstream of the NF-κB transcription factor. Deletion of TRAF-binding sites in GRA15 greatly reduces its ability to activate the NF-κB pathway, and TRAF2 knockout cells have impaired GRA15-mediated NF-κB activation. Thus, we determined the mechanism for GRA15-dependent NF-κB activation.
Bulka CM, Dammann O, Santos HP, VanderVeen DK, Smeester L, Fichorova R, O'Shea MT, Fry RC. Placental CpG Methylation of Inflammation, Angiogenic, and Neurotrophic Genes and Retinopathy of Prematurity. Invest Ophthalmol Vis Sci 2019;60(8):2888-2894.Abstract
Purpose: Extremely preterm infants are at increased risk for retinopathy of prematurity (ROP). We previously identified several inflammatory proteins that were expressed early in life and are associated with an increased risk of ROP and several angiogenic and neurotrophic growth factors in the neonatal systemic circulation that are associated with a lower risk of ROP. In this paper, we report the results of a set of analyses designed to test the hypothesis that placental CpG methylation levels of 12 inflammation-, angiogenic-, and neurotrophic-associated genes predict the occurrence of prethreshold ROP in extremely preterm newborns. Methods: We used placental CpG methylation data from 395 newborns from the Extremely Low Gestational Age Newborns study. Results: Multivariable regression models revealed that placental DNA methylation of 16 CpG sites representing 8 genes were associated with prethreshold ROP. Specifically, CpG methylation in the serum amyloid A SAA1 and SAA2, brain-derived neurotrophic factor (BDNF), myeloperoxidase (MPO), C-reactive protein (CRP), angiopoietin 1 (ANGPT1), and tumor necrosis factor receptor superfamily member 1B (TNFRSF1B) genes was associated with a lower risk of prethreshold ROP. Conversely, CpG methylation at three probes within tumor necrosis factor receptor superfamily member 1A (TNFRSF1A) and in two alternative probes within the BDNF and ANGPT1 genes was associated with an increased risk of ROP. Conclusions: CpG methylation may be a useful marker for improving ROP prediction, opening the opportunity for early intervention to lessen disease severity.
Parikh R, Avery RL, Saroj N, Thompson D, Freund BK. Incidence of New Choroidal Neovascularization in Fellow Eyes of Patients With Age-Related Macular Degeneration Treated With Intravitreal Aflibercept or Ranibizumab. JAMA Ophthalmol 2019;Abstract
Importance: Incidence of conversion to neovascular age-related macular degeneration (nAMD) in untreated fellow eyes of patients who are treated for nAMD in 1 eye with anti-vascular endothelial growth factor agents provides important prognostic information to clinically manage patients. Objective: To investigate the association of treatment assignment (intravitreal aflibercept vs ranibizumab) and baseline characteristics with fellow eye conversion to nAMD in the VEGF (Vascular Endothelial Growth Factor) Trap-Eye: Investigation of Efficacy and Safety in Wet AMD (VIEW) studies. Design, Setting, and Participants: This post hoc analysis of the VIEW 1 and VIEW 2 studies (randomized, double-masked, active-controlled, multicenter, 96-week, phase 3 trials comparing the efficacy and safety of intravitreal aflibercept in 2457 patients with treatment-naive eyes with nAMD) analyzed a subgroup of participants treated for nAMD in 1 eye who had untreated fellow eyes without neovascularization at baseline. All participants in the VIEW studies were included in 1 of 4 groups: ranibizumab, 0.5 mg, every 4 weeks; aflibercept, 2 mg, every 4 weeks; aflibercept, 0.5 mg, every 4 weeks; or aflibercept, 2 mg, every 8 weeks after 3 injections at 4-week intervals. Data collection in the VIEW studies occurred from July 2007 to August 2011; the data analysis presented in this report took place from April 2016 to November 2018. Interventions: Patients received no treatment in the fellow eyes unless after conversion to nAMD, when any treatment approved by heath authorities was given per the investigators' discretion. Main Outcomes and Measures: Incidence of conversion to nAMD in patients with untreated fellow eyes that had not had clinical signs of neovascularization at baseline. Results: A total of 1561 participants were included in this analysis. At 96 weeks, 375 patients (24.0%) experienced cases of conversion to neovascular disease in the fellow eye, including 107 of the 399 individuals who received ranibizumab, 0.5 mg, every 4 weeks; 93 of the 387 individuals who received aflibercept, 2 mg, every 4 weeks; 84 of the 387 individuals who received aflibercept, 0.5 mg, every 4 weeks; and 91 of the 388 individuals who received aflibercept, 2 mg, every 8 weeks after 3 doses at 4-week intervals. The rates were 18.1, 16.2, 14.7, and 16.0 per 100 patient-years at risk at week 96, respectively. On multivariate analysis, fellow eye conversion was associated with increasing patient age (per 10 years) at baseline (hazard ratio [HR], 1.20 [95% CI, 1.05-1.36]), female sex (HR, 1.32 [95% CI, 1.06-1.63]), intraretinal fluid in the study eye at baseline (HR, 1.28 [95% CI, 1.02-1.61]), and increasing choroidal neovascularization lesion size (per 10 mm2) in the study eye at baseline (HR, 1.29 [95% CI, 1.06-1.57]). Rates of fellow eye conversion were similar with either of the treatments. Conclusions and Relevance: In this secondary analysis of randomized clinical trial data, patients with active nAMD in 1 eye appeared to have a high risk for fellow eye conversion. Such patients should be monitored closely.
Fine RL, Manfredo Vieira S, Gilmore MS, Kriegel MA. Mechanisms and consequences of gut commensal translocation in chronic diseases. Gut Microbes 2019;:1-14.Abstract
Humans and other mammalian hosts have evolved mechanisms to control the bacteria colonizing their mucosal barriers to prevent invasion. While the breach of barriers by bacteria typically leads to overt infection, increasing evidence supports a role for translocation of commensal bacteria across an impaired gut barrier to extraintestinal sites in the pathogenesis of autoimmune and other chronic, non-infectious diseases. Whether gut commensal translocation is a cause or consequence of the disease is incompletely defined. Here we discuss factors that lead to translocation of live bacteria across the gut barrier. We expand upon our recently published demonstration that translocation of the gut pathobiont can induce autoimmunity in susceptible hosts and postulate on the role of species as instigators of chronic, non-infectious diseases.
Dorr M, Kwon MY, Lesmes LA, Miller A, Kazlas M, Chan K, Hunter DG, Lu Z-L, Bex PJ. Binocular Summation and Suppression of Contrast Sensitivity in Strabismus, Fusion and Amblyopia. Front Hum Neurosci 2019;13:234.Abstract
: Amblyopia and strabismus affect 2%-5% of the population and cause a broad range of visual deficits. The response to treatment is generally assessed using visual acuity, which is an insensitive measure of visual function and may, therefore, underestimate binocular vision gains in these patients. On the other hand, the contrast sensitivity function (CSF) generally takes longer to assess than visual acuity, but it is better correlated with improvement in a range of visual tasks and, notably, with improvements in binocular vision. The present study aims to assess monocular and binocular CSFs in amblyopia and strabismus patients. : Both monocular CSFs and the binocular CSF were assessed for subjects with amblyopia ( = 11), strabismus without amblyopia ( = 20), and normally sighted controls ( = 24) using a tablet-based implementation of the quick CSF, which can assess a full CSF in <3 min. Binocular summation was evaluated against a baseline model of simple probability summation. : The CSF of amblyopic eyes was impaired at mid-to-high spatial frequencies compared to fellow eyes, strabismic eyes without amblyopia, and control eyes. Binocular contrast summation exceeded probability summation in controls, but not in subjects with amblyopia (with or without strabismus) or strabismus without amblyopia who were able to fuse at the test distance. Binocular summation was less than probability summation in strabismic subjects who were unable to fuse. : We conclude that monocular and binocular contrast sensitivity deficits define important characteristics of amblyopia and strabismus that are not captured by visual acuity alone and can be measured efficiently using the quick CSF.
Koulisis N, Moysidis SN, Yonekawa Y, Dai YL, Burkemper B, Wood EH, Lertjirachai I, Todorich B, Khundkar TZ, Chu Z, Wang RK, Williams GA, Drenser KA, Capone A, Trese MT, Nudleman E. Correlating Changes in the Macular Microvasculature and Capillary Network to Peripheral Vascular Pathologic Features in Familial Exudative Vitreoretinopathy. Ophthalmol Retina 2019;3(7):597-606.Abstract
PURPOSE: To evaluate the macular microvasculature in patients with familial exudative vitreoretinopathy (FEVR) using OCT angiography (OCTA) and to assess for peripheral vascular changes using widefield fluorescein angiography (WFA). DESIGN: Multicenter, retrospective, comparative, observational case series. PARTICIPANTS: We identified 411 patients with FEVR, examined between September 2014 and June 2018. Fifty-seven patients with FEVR and 60 healthy controls had OCTA images of sufficient quality for analysis. METHODS: Custom software was used to assess for layer-specific, quantitative changes in vascular density and morphologic features on OCTA by way of vessel density (VD), skeletal density (SD), fractal dimension (FD), vessel diameter index (VDI), and foveal avascular zone (FAZ). Widefield fluorescein angiography images were reviewed for peripheral vascular changes including capillary dropout, late-phase angiographic posterior and peripheral vascular leakage (LAPPEL), vascular dragging, venous-venous shunts, and arteriovenous shunts. MAIN OUTCOME MEASURES: Macular microvascular parameters on OCTA and peripheral angiographic findings on WFA. RESULTS: OCT angiography analysis of 117 patients (187 eyes; 92 FEVR patients and 95 control participants) demonstrated significantly reduced VD, SD, and FD and greater VDI in patients with FEVR compared with controls in the nonsegmented retina, superficial retinal layer (SRL), and deep retinal layer (DRL). The FAZ was larger compared with that in control eyes in the DRL (P < 0.0001), but not the SRL (P = 0.52). Subanalysis by FEVR stage showed the same microvascular changes compared with controls for all parameters. Widefield fluorescein angiography analysis of 95 eyes (53 patients) with FEVR demonstrated capillary nonperfusion in all eyes: 47 eyes (49.5%) showed LAPPEL, 32 eyes (33.7%) showed vascular dragging, 30 eyes (31.6%) had venous-venous shunts, and 33 eyes (34.7%) had arteriovenous shunts. Decreasing macular VD on OCTA correlated with increasing peripheral capillary nonperfusion on WFA. Decreasing fractal dimension on OCTA correlated with increasing LAPPEL severity on WFA. CONCLUSIONS: Patients with FEVR demonstrated abnormalities in the macular microvasculature and capillary network, in addition to the peripheral retina. The macular microvascular parameters on OCTA may serve as biomarkers of changes in the retinal periphery on WFA.
Shukla S, Mittal SK, Foulsham W, Elbasiony E, Singhania D, Sahu SK, Chauhan SK. Therapeutic efficacy of different routes of mesenchymal stem cell administration in corneal injury. Ocul Surf 2019;Abstract
PURPOSE: Corneal injuries are associated with significant impairment in vision. Mesenchymal stem cells (MSCs) have been shown to limit inflammation and promote tissue repair at the ocular surface. Here, we evaluate the efficacies of different modes of MSC delivery (topical, subconjunctival, intraperitoneal [IP] and intravenous [IV]) to promote tissue repair and restore corneal transparency in a murine model of corneal injury. METHODS: MSCs were purified from the bone marrow of C57BL/6 J mice and expanded using plastic adherence in vitro. Corneal injury was created using an Algerbrush, and 0.5 × 10 MSCs/mouse were administered via topical, subconjunctival, IP or IV routes. Qdot-labeled MSCs were employed to determine the effect of route of administration on corneal and conjunctival MSC frequencies. Corneal opacity scores were calculated using ImageJ. Expression of inflammatory cytokines was quantified by qPCR, and infiltration of CD45 cells was evaluated by flow cytometry. RESULTS: Subconjunctival or IV administration results in increased frequencies of MSCs in ocular surface tissues following corneal injury, relative to topical or intraperitoneal delivery. Subconjunctival or IV administration reduces: (i) corneal opacity, (ii) tissue fibrosis as quantified by α-Sma expression, (iii) the expression of inflammatory cytokines (Il-1β and Tnf-α) and (iv) CD45 inflammatory cell infiltration relative to untreated injured control animals. Administration via subconjunctival or IV routes was observed to accelerate corneal repair by restoring tissue architecture and epithelial integrity. CONCLUSIONS: Our data suggest that subconjunctival or IV delivery of MSCs have superior therapeutic efficacy compared to topical or IP delivery following corneal injury.
Uchi S-H, Yanai R, Kobayashi M, Hatano M, Kobayashi Y, Yamashiro C, Nagai T, Tokuda K, Connor KM, Sonoda K-H, Kimura K. Dendritic cells mediate the anti-inflammatory action of omega-3 long-chain polyunsaturated fatty acids in experimental autoimmune uveitis. PLoS One 2019;14(7):e0219405.Abstract
We previously showed that dietary omega (ω)-3 long-chain polyunsaturated fatty acids (LCPUFAs) suppress inflammation in mice with experimental autoimmune uveitis (EAU). We have now investigated the role of antigen presenting cells (APCs) in this action of ω-3 LCPUFAs. C57BL/6 mice were fed a diet supplemented with ω-3 or ω-6 LCPUFAs for 2 weeks, after which splenocytes were isolated from the mice and cocultured with CD4+ T cells isolated from mice with EAU induced by injection of a human interphotoreceptor retinoid-binding protein peptide together with complete Freund's adjuvant. The proliferation of and production of interferon-γ and interleukin-17 by T cells from EAU mice in vitro were attenuated in the presence of splenocytes from ω-3 LCPUFA-fed mice as compared with those from mice fed ω-6 LCPUFAs. Splenocyte fractionation by magnetic-activated cell sorting revealed that, among APCs, dendritic cells (DCs) were the target of ω-3 LCPUFAs. Adoptive transfer of DCs from mice fed ω-3 LCPUFAs attenuated disease progression in EAU mice as well as the production of pro-inflammatory cytokines by T cells isolated from these latter animals. The proliferation of T cells from control Balb/c mice was also attenuated in the presence of DCs from ω-3 LCPUFA-fed mice as compared with those from ω-6 LCPUFA-fed mice. Furthermore, T cell proliferation in such a mixed lymphocyte reaction was inhibited by prior exposure of DCs from mice fed an ω-6 LCPUFA diet to ω-3 LCPUFAs in vitro. Our results thus suggest that DCs mediate the anti-inflammatory action of dietary ω-3 LCPUFAs in EAU.
Papadopoulos Z. Aflibercept: A review of its effect on the treatment of exudative age-related macular degeneration. Eur J Ophthalmol 2019;29(4):368-378.Abstract
Considerable improvement has been achieved in the way in which exudative age-related macular degeneration is conventionally treated and in the associated visual outcomes and prognosis, thanks to the agents with effects against vascular endothelial growth factor (anti-VEGF). By comparison to earlier treatment approaches that involved the use of lasers, the anti-VEGF agents have made it possible to accomplish more positive visual and anatomical outcomes in cases of exudative age-related macular degeneration. Indeed, owing to their positive effects, anti-VEGF agents have quickly come to be considered the gold standard for the treatment of wet age-related macular degeneration. Aflibercept, the most recently approved intravitreally administered anti-VEGF, seems to mark another milestone in the treatment of wet age-related macular degeneration. This anti-VEGF agent presents a series of singular pharmacodynamic and pharmacokinetic attributes that provide it a number of biological benefits in relation to the treatment of choroidal neovascularization compared to other agents. These attributes include high level of affinity for the VEGF-A factor, an intravitreal half-life of great length, as well as the ability to serve as an antagonist for other growth factors besides VEGF. The impact of Aflibercept on the manner in which exudative age-related macular degeneration is managed was demonstrated by thoroughly reviewing the related literature. The present review article highlights the pharmacology, pharmacokinetics, safety and effectiveness of this anti-VEGF agent as well as the landmark clinical studies that have been carried out to establish this drug as a gold standard in the therapy of neovascular age-related macular degeneration. In addition, studies regarding the outcomes and effectiveness of the various dosage regimens, either as monotherapy or in combination with other agents, are also reviewed.
Laíns I, Chung W, Kelly RS, Gil J, Marques M, Barreto P, Murta JN, Kim IK, Vavvas DG, Miller JB, Silva R, Lasky-Su J, Liang L, Miller JW, Husain D. Human Plasma Metabolomics in Age-Related Macular Degeneration: Meta-Analysis of Two Cohorts. Metabolites 2019;9(7)Abstract
The pathogenesis of age-related macular degeneration (AMD), a leading cause of blindness worldwide, remains only partially understood. This has led to the current lack of accessible and reliable biofluid biomarkers for diagnosis and prognosis, and absence of treatments for dry AMD. This study aimed to assess the plasma metabolomic profiles of AMD and its severity stages with the ultimate goal of contributing to addressing these needs. We recruited two cohorts: Boston, United States ( = 196) and Coimbra, Portugal ( = 295). Fasting blood samples were analyzed using ultra-high performance liquid chromatography mass spectrometry. For each cohort, we compared plasma metabolites of AMD patients versus controls (logistic regression), and across disease stages (permutation-based cumulative logistic regression considering both eyes). Meta-analyses were then used to combine results from the two cohorts. Our results revealed that 28 metabolites differed significantly between AMD patients versus controls (false discovery rate (FDR) -value: 4.1 × 10-1.8 × 10), and 67 across disease stages (FDR -value: 4.5 × 10-1.7 × 10). Pathway analysis showed significant enrichment of glycerophospholipid, purine, taurine and hypotaurine, and nitrogen metabolism (-value ≤ 0.04). In conclusion, our findings support that AMD patients present distinct plasma metabolomic profiles, which vary with disease severity. This work contributes to the understanding of AMD pathophysiology, and can be the basis of future biomarkers and precision medicine for this blinding condition.
AbuSamra DB, Mauris J, Argüeso P. Galectin-3 initiates epithelial-stromal paracrine signaling to shape the proteolytic microenvironment during corneal repair. Sci Signal 2019;12(590)Abstract
Paracrine interactions between epithelial cells and stromal fibroblasts occur during tissue repair, development, and cancer. Crucial to these processes is the production of matrix metalloproteinases (MMPs) that modify the microenvironment. Here, we demonstrated that the carbohydrate-binding protein galectin-3 stimulated microenvironment remodeling in the cornea by promoting the paracrine action of secreted interleukin-1β (IL-1β). Through live cell imaging in vitro, we observed rapid activation of the promoter in clusters of cultured human epithelial cells after direct heterotypic contact with single primary human fibroblasts. Soluble recombinant galectin-3 and endogenous galectin-3 of epithelial origin both stimulated MMP9 activity through the induction of IL-1β secretion by fibroblasts. In vivo, mechanical disruption of the basement membrane in wounded corneas prompted an increase in the abundance of IL-1β in the stroma and increased the amount of gelatinase activity in the epithelium. Moreover, corneas of galectin-3-deficient mice failed to stimulate IL-1β after wounding. This mechanism of paracrine control has broad importance for our understanding of how the proteolytic microenvironment is modified in epithelial-stromal interactions.
Sauvage F, Fraire JC, Remaut K, Sebag J, Peynshaert K, Harrington M, Van de Velde FJ, Xiong R, Tassignon M-J, Brans T, Braeckmans K, De Smedt SC. Photoablation of Human Vitreous Opacities by Light-Induced Vapor Nanobubbles. ACS Nano 2019;13(7):8401-8416.Abstract
Myopia, diabetes, and aging are the main causes of progressive vitreous collagen aggregation, resulting in vitreous opacities, which can significantly disturb vision. As vitreous opacities, which induce the visual phenomenon of "floaters", are accessible with nanomaterials and light, we propose a nanotechnology-based approach to locally ablate them with highly reduced light energy compared to the more traditional YAG laser therapy. Our strategy relies on the plasmon properties of gold nanoparticles that generate vapor nanobubbles upon pulsed-laser illumination whose mechanical force can ablate vitreous opacities. We designed gold nanoparticles coated with hyaluronic acid (HA), which have excellent diffusional mobility in human vitreous, an essential requirement to reach the vitreous opacities. In addition, we found that HA-coated gold nanoparticles can accumulate extensively on human vitreous opacities that were obtained by vitrectomy from patients with vision-degrading myodesopsia. When subsequently applying nanosecond laser pulses, the collagen aggregates were efficiently destroyed with ∼1000 times less light energy than typically used in YAG laser therapy. This low-energy "floater-specific destruction", which is due to the accumulation of the small gold nanoparticles on the opacities, is attractive, as it may be safer to the surrounding ocular tissues while at the same time being easier and faster to apply compared to YAG laser therapy, where the opacities need to be ablated piece by piece by a tightly focused laser beam. Gold nanoparticle-assisted photoablation may therefore provide a safer, faster, and more reliable destruction of vitreous opacities in the treatment of ophthalmologic diseases.

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