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.

In this study, we aimed to develop a deep learning model for identifying bacterial keratitis (BK) and fungal keratitis (FK) by using slit-lamp images. We retrospectively collected slit-lamp images of patients with culture-proven microbial keratitis between 1 January 2010 and 31 December 2019 from two medical centers in Taiwan. We constructed a deep learning algorithm consisting of a segmentation model for cropping cornea images and a classification model that applies different convolutional neural networks (CNNs) to differentiate between FK and BK. The CNNs included DenseNet121, DenseNet161, DenseNet169, DenseNet201, EfficientNetB3, InceptionV3, ResNet101, and ResNet50. The model performance was evaluated and presented as the area under the curve (AUC) of the receiver operating characteristic curves. A gradient-weighted class activation mapping technique was used to plot the heat map of the model. By using 1330 images from 580 patients, the deep learning algorithm achieved the highest average accuracy of 80.0%. Using different CNNs, the diagnostic accuracy for BK ranged from 79.6% to 95.9%, and that for FK ranged from 26.3% to 65.8%. The CNN of DenseNet161 showed the best model performance, with an AUC of 0.85 for both BK and FK. The heat maps revealed that the model was able to identify the corneal infiltrations. The model showed a better diagnostic accuracy than the previously reported diagnostic performance of both general ophthalmologists and corneal specialists.

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To evaluate the outcome of a novel, modified 23-gauge vitrectomy system in the treatment of stage 4 retinal detachment in retinopathy of prematurity. Methods: Consecutive patients with stage 4 retinopathy of prematurity treated with modified 23-gauge vitrectomy were included in this medical record review. Major novel modifications included the use of a small infusion cannula, a 20-gauge blade for the creation of sclerotomies in the pars plicata, and a 23-gauge endoilluminator and vitreous cutter. Conjunctival dissection and suturing of sclerotomies were performed using this modified 3-port, 23-gauge vitrectomy technique. Anatomic success and surgical complications were analyzed. Results: Twenty-six eyes of 17 patients were included and analyzed. The mean (SD) gestational age was 28.0 (2.5) weeks, and the mean birth weight was 1199 (449) g. Mean postmenstrual age at the time of vitrectomy was 40.5 (3.0) weeks. Overall, 20 eyes (77%) achieved retinal attachment in a single operation, and 23 eyes (88%) achieved retinal attachment after multiple procedures. Postoperative complications included disc dragging (5 eyes [19%]), cataracts (4 [15%]), glaucoma (2 [8%]), persistent vitreous hemorrhage (1 [4%]), and posterior synechia (1 [4%]). Conclusions: This 23-gauge vitrectomy system seems to be a safe and effective approach for treatment of stage 4 retinopathy of prematurity. This modified system combines the benefits of 20-and 23-gauge vitrectomy and offers safer insertion of infusion cannulas in smaller eyes, more working space in pediatric eyes, a cutting port that is closer to the retina, and a faster cutting speed with less vitreous traction during the operation.

Myopia and congenital or developmental disease are the leading etiologies of pediatric rhegmatogenous retinal detachment. Different etiologies are associated with distinctive outcomes, and congenital and developmental diseases are independent prognostic factors of a poor response.