Internal-tamponade agents are crucial surgical adjuncts in vitreoretinal surgery. Clinically used endotamponade agents act through buoyancy forces, yet can result in prolonged post-operative positioning, temporary loss of vision, raised intra-ocular pressure, cataract formation or the need for additional removal surgery. Here, we describe a thermogelling polymer that provides an internal tamponade effect through surface tension and swelling counter-forces. We tested the long-term biocompatibility of the polymer endotamponade in rabbit vitrectomy models, and its surgical efficacy and biocompatibility in a non-human primate retinal-detachment model. We also show that, while the thermogel biodegrades during the three months following surgery, it promotes the reformation of a vitreous-like body that mimics the biophysical properties of the natural vitreous. The thermogelling endotamponade might serve as a long-term vitreous substitute.
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The authors declare that all data supporting the results in this study are available within the paper and its Supplementary Information. The MS proteomics data have been deposited to the ProteomeXchange Consortium (http://proteomecentral.proteomexchange.org/) via the PRIDE partner repository, with the dataset identifier PXD009525.
Publisher’s note: Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
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This study was supported by a Biomedical Engineering Programme (BEP) grant, A*STAR, Singapore (2014 POC/1521480032), the NUS Start-up grant NUHSRO/2016/100/SU/01 and IAF-PP (HMBS Domain) H17/01/a0/013 (OrBID): OculaR BIomaterials and Device. We would like to acknowledge the veterinary team at the Translational Pre-Clinical Model Platform (Singapore Eye Research Institute, Singapore) for providing support in NHP surgery preparation and animal follow-up.
Supplementary figures, and video and table captions.
List of proteins identified by MS-based LFQ proteomics analysis.
Gel injection in the rabbit eye.
Dissection of the EPC-filled eye, 3 months post-operation.
Dissection of the native vitreous.
Dissection of the operated control (BSS-filled eye), 3 months post-operation.
SD-OCT volume scan of the retinotomy site of the non-human primate, 12 months post-operation.
SD-OCT volume scan of the macula of the non-human primate, 2 months post-operation.