Photoablation of Human Vitreous Opacities by Light-Induced Vapor Nanobubbles

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 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 which were obtained by vitrectomy from patients with vision degrading myodesopsia. When subsequently applying 2 nanosecond laser pulses, the collagen aggregates were efficiently destroyed with ~1000 times less light energy as 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 photo-ablation may therefore provide a safer, faster and more reliable destruction of vitreous opacities in the treatment of ophthalmologic diseases.

Nanomaterials to avoid and destroy protein aggregates

“…As the eye is easily accessible to both light and advanced materials, our group has an interest in photothermal treatment of ophthalmological diseases. Recently we explored to which extent VNB may be suitable to destroy vitreous opacities (also named 'floaters') [105] ( Figure 8B). Eye floaters are protein aggregates mostly composed of a mixture of different types of collagen that are present in the vitreous [106,107].…”

“…However, in vivo toxicity studies still need to be performed. vitrectomy of a patient treated with 10 nm HA-AuNPs respectively before and after illumination with a nanosecond laser ( 3 pulses of 800 µJ (adapted from [105]).…”

Spontaneous posterior vitreous detachment: A glance at the current literature

“…If symptoms are clinically important and visual acuity levels drop, treatment can be considered. Vitrectomy is the gold-standard surgical treatment for patients with vision-degrading myodesopsia[ 30 ]. Of course, that option is used in a very limited number of cases considering the risks associated with this invasive surgery.…”

“…Of course, that option is used in a very limited number of cases considering the risks associated with this invasive surgery. The other options that are currently being studied involve treatment with Nd:YAG laser vitreolysis[ 31 ] and photoablation[ 30 ]. However, those treatments are still experimental and not often used in routine clinical practice.…”

Synergic Effect of Novel WS2 Carriers Holding Spherical Cobalt Ferrite @cubic Fe3O4 (WS2/s-CoFe2O4@c-Fe3O4) Nanocomposites in Magnetic Resonance Imaging and Photothermal Therapy for Ocular Treatments and Investigation of Corneal Endothelial Cell Migration

“…In this regard, various types of nanoparticles (NPs) are found to assist laser treatments specially for treatment of eye diseases [17,18]. Sauvage et al reported on applying laser to ablate the plasmonic NPs conjugated with the vitreous opacities as feasible treatments for eye diseases [19]. In other research, laser has been used to trigger graphene nanosheets to release the drugs inside the eyes after administrations [20][21][22].…”