The antibody bevacizumab (Avastin) has been used clinically to treat intraocular neovascular diseases based on its antivascular endothelial growth factor (VEGF) character. The anti-VEGF strategy for retinal neovascular diseases is limited by the short half-life of bevacizumab and thus requires frequent injections. This Article reports the sustained release of bevacizumab from a biocompatible material that is composed of a triblock copolymer of poly(2-ethyl-2-oxazoline)-b-poly(ε-caprolactone)-b-poly(2-ethyl-2-oxazoline) (PEOz-PCL-PEOz). The amphiphilic PEOz-PCL-PEOz triblock copolymer was synthesized in three steps. First, the PEOz was polymerized by methyl p-toluenesulfonate and 2-ethyl-2-oxazoline (EOz), and the living end was terminated by potassium hydroxide methanolic solution. Subsequently, the hydroxyl-PEOz was used as a macroinitiator for the ring-opening polymerization of ε-caprolactone using a Tin(II) octoate catalyst to synthesize the telechelic hydroxylated PEOz-PCL. Finally, the PEOz-PCL-PEOz triblock copolymer was obtained using the 1,6-hexamethylene diisocyanateas a coupling reagent. The PEOz-PCL-PEOz was chemically and molecularly characterized by GPC, (1)H NMR, and FTIR, and its aqueous solution (ECE hydrogel) showed a reversible sol (room temperature)-gel (physiological temperature) phase transition, which serves as an easy antibody-packing system with extended release. The biodegradability of ECE hydrogel was assessed by the porosity formation at different periods by scanning electron microscopy. The ECE hydrogel had no in vitro cytotoxicity on the human retinal pigment epithelial cell line by flow cytometry. The histomorphology and electrophysiology of the rabbit neuroretina were preserved after 2 months of intravitreal injection. In conclusion, the ECE hydrogel has a temperature-sensitive sol-gel phase transition and is effective in vitro. Its intraocular biocompatibility demonstrated its great potential to be widely used in biomedical applications for extended drug release.

Purpose: To determine the rates and risk factors of recurrent retinopathy of prematurity (ROP) treated by laser photocoagulation, intravitreal bevacizumab (IVB) monotherapy, or intravitreal ranibizumab (IVR) monotherapy. Methods: In this retrospective cohort study, consecutive infants with Type 1 ROP who received laser, IVB, or IVR treatments were followed for at least 75 weeks of postmenstrual age. Data analysis was performed between March 2010 and February 2017 in Chang Gung Memorial Hospital, Linkou, Taiwan. Results: A total of 176 infants (340 eyes) were included in this study. The mean follow-up was 197.3 ± 110 weeks. All of the baseline demographic and ROP characteristics among the laser, IVB, and IVR groups were similar. The overall recurrence rate after treatment was 44 of 340 eyes (12.9%). The IVB group had a recurrence rate of 10.0%, followed by the laser group (18.0%) and the IVR group (20.8%); however, these rates were not significantly different (P = 0.0528). Compared with the laser group, the IVB and IVR groups exhibited recurrence at later ages (43.4 ± 3.5 weeks for the IVB group, 42.3 ± 2.0 weeks for the IVR group, and 39.5 ± 2.8 weeks for the laser group; P = 0.0058). The mean interval of recurrence from initial treatment in the laser group was 3.6 ± 1.4 weeks compared with 8.8 ± 3.9 weeks and 8.3 ± 1.6 weeks in the IVB and IVR groups, respectively (P = 0.0001). Overall, the independent risk factors of recurrence included an early postmenstrual age at initial treatment (P = 0.0160), Zone I (P = 0.0007), low Apgar score (P = 0.0297), and multiple births (P = 0.0285). There was no significant difference in progression to retinal detachment among the three groups (laser: 3/61, 4.9%; IVB: 2/231, 0.9%;and IVR: 1/48, 2.1%; P = 0.2701). Conclusion: Laser, IVR, and IVB are effective for Type 1 ROP. Retinopathy of prematurity recurrence requiring re-treatment was encountered as late as 50 weeks of postmenstrual age after IVB or IVR but earlier after laser. Longer follow-up for infants treated with anti–vascular endothelial growth factor is needed, especially in patients with significant risk factors such as an early postmenstrual age at initial treatment, Zone I ROP, low Apgar score, and multiple births.

BackgroundTo evaluate the surgical technique using autologous retinal graft (ARG) and autologous blood clot (ABC) for the management of refractory macular holes (MHs).MethodsThis study was a retrospective, consecutive, interventional case series. Six eyes of 6 patients who underwent vitrectomy combined with ARG and ABC for the treatment of refractory MH were reviewed. Visual and anatomic outcomes were evaluated.ResultsThe mean age was 59.0 ± 9.9 years. All cases had multiple vitreoretinal procedures including vitrectomy and gas fluid exchange before patient presentation. The average numbers of vitrectomies were 2.3 ± 0.5, and those of gas fluid exchange were 3 ± 1.7. Closure of the macular hole was achieved in four (66.7%) cases at last follow-up. The mean follow-up time was 25.2 ± 15.6 months. The averaged BCVA before and after 12 months of the surgery improved from 20/591 to 20/244.ConclusionsThis surgical technique using ARG and ABC provide an option for the treatment of refractory MHs.Electronic supplementary materialThe online version of this article (10.1186/s12886-018-0898-8) contains supplementary material, which is available to authorized users.

Due to differences in aetiologies, clinical characteristics, required surgical procedure after initial repair, surgical and functional outcomes, paediatric RD with extreme myopia should be addressed differently from paediatric RD with high myopia.