Technical Standards of a Foldable Capsular Vitreous Body in Terms of Mechanical, Optical, and Biocompatible Properties

Abstract

We previously proposed a new strategy to fabricate a novel foldable capsular vitreous body (FCVB) as a vitreous substitute and found that the FCVB was a very good replacement for closely mimicking the morphology and restoring the physiologic function of the rabbit vitreous body. The aim of this article was to assess the mechanical, optical, and biocompatible properties of a FCVB made from liquid silicone rubber. The mechanical properties show that the shore hardness is 37.80 degrees, the tear strength is 47.14 N/mm, the tensile strength is more than 7.28 MPa, and the elongation ratio is more than 1200%; in addition, the FCVB has 300 nm mili apertures in the capsule. The optical properties reveal that transmittances are 92%, hazes are 5.74%, and spectral transmittance is 97%. The transmittance mission is 2.3% and can sustain a 1500 mW, 0.2 s, 532 nm green laser. The biocompatible properties are shown in the stable extracts experiment, no significant fever, good genetic safety, and no structural abnormality or apoptosis in the cornea, ciliary body, and retina over a 6-month observation period. These results indicate that the FCVB has good mechanical, optical, and biocompatible properties, and the assessment results can be recommended as the FCVB technical standards for industrial manufacturing and inspection.

Evaluation of supporting role of a foldable capsular vitreous body with magnetic resonance imaging in the treatment of severe retinal detachment in human eyes

“…16,17 In previous studies, we proposed a new strategy to replace the natural vitreous body using a novel foldable capsular vitreous body (FCVB). [18][19][20][21] The FCVB consisted of a thin, vitreous-shaped capsule with a tube-valve system created using computer and industrial technology. After foldable installation into the eye, a balanced salt solution (BSS) could be injected into the capsule and inflated to support the retina and control the intraocular pressure through the tube-valve system.…”

“…19 Reports from the Chinese State Food and Drug Administration show that the FCVB has good mechanical, optical, and biocompatible properties. 20 As the FCVB has never been used in eyes worldwide, we conducted an exploratory study of 11 patients implanted by FCVB with BSS in the treatment of severe retinal detachment at Zhongshan Ophthalmic Centre and found it had good flexibility, safety, and efficacy during a 3-month study period. 21 As the FCVB is made of silicone rubber, magnetic resonance imaging (MRI) might provide valuable information on the role of the FCVB in supporting the retina and eye.…”

A Novel Artificial Vitreous Substitute - Foldable Capsular Vitreous Body

“…49 Reports from the State FDA in China show that FCVB has suitably mechanical, optical, and biocompatibility properties. 50 Its optical characteristics indicate that FCVB has high light transmission and laser irradiation stability.…”

“…Figure 1 and Table 2 show the images and parameters of the FCVB, respectively. 50 Silicone rubber elastomer has been used for tissue augmentation for many years, [43][44][45] so it was utilized to manufacture the capsule of FCVB. It showed good oxygen permeability, good mechanical and optical properties (Shore A hardness: 37.4 。 , tensile intensity: >5.86 MPa, elongation ratio: >1200%, tear intensity: 34KN/m, transmittance: 93%, Hazes<1%), 46 and good biocompatibility as shown in stable extracts experiment (no significant fever, good genetic safety, and no structural abnormality or apoptosis in the cornea, ciliary body, and retina over a six-month observation period).…”

“…It showed good oxygen permeability, good mechanical and optical properties (Shore A hardness: 37.4 。 , tensile intensity: >5.86 MPa, elongation ratio: >1200%, tear intensity: 34KN/m, transmittance: 93%, Hazes<1%), 46 and good biocompatibility as shown in stable extracts experiment (no significant fever, good genetic safety, and no structural abnormality or apoptosis in the cornea, ciliary body, and retina over a six-month observation period). 50 After pars plana vitrectomy, the seamlessly connected FCVB was triple-folded and inserted into the vitreous cavity through a 3 mm × 1 mm scleral incision without air fluid exchange. Then an injectable medium, such as balanced salt solution (BSS) or silicone oil, can be injected into the capsule and inflated to support the retina.…”