The human sclera accounts for 95% of the surface of the eyeball, providing ample contact area which is suitable for targeted trans-scleral ocular drug delivery. Currently there are several tans-scleral sustained-release strategies, including intra-scleral delivery, episcleral delivery, as well as tans-scleral iontophoresis. Different devices and methods have their own advantages and disadvantages, for example, intra-scleral delivery is somehow invasive, and episcleral delivery device needs to be made thin to prevent erosion of conjunctiva, iontophoresis needs to be frequently repeated as of its short-term effect. With the development of bio-material engineering technology, episcleral microfilm could become an ideal drug delivery route for posterior segment ocular diseases.
ObjectiveTo observe the clinical efficacy of dexamethasone intravitreal implant (DEX) in the treatment of active non-infectious uveitis macular edema (NIU-ME).MethodsA retrospective observational study. From February 2018 to February 2019, 23 patients (26 eyes) were included in the study who were diagnosed with NIU-ME at the Department of Ophthalmology, Central Theater Command General Hospital and received intravitreal DEX treatment. Among 23 patients, there were 8 males (8 eyes) and 15 females (18 eyes); the average age was 46.9 years; the average course of disease was 9.2±2.4 months. All the affected eyes underwent BCVA and intraocular pressure examination; at the same time, OCT was used to measure the central retinal thickness (CMT) of the macula. Snellen visual acuity chart was used for visual inspection. The average BCVA of the affected eye was 0.281±0.191, the average intraocular pressure was 16.2±0.8 mmHg (1 mmHg=0.133 kPa), and the average CMT was 395.4±63.7 μm. Among the 23 patients, 8 patients had middle uveitis and 15 patients had posterior uveitis. Seven patients had received intravenous infusion of methylprednisolone, 5 patients had been treated with methylprednisolone combined with immunosuppressive agents, and 11 patients had not received any treatment. All the affected eyes were treated with DEX intravitreal injection. Patients received repeated visual acuity, intraocular pressure and OCT examination with follow-up after injection. During the follow-up period, patients with recurrence of edema or poor efficacy, systemic methylprednisolone and intravitreal reinjection of DEX, triamcinolone acetonide or methotrexate should be considered based on the patient's own conditions. We observed the changes of BCVA, intraocular pressure and CMT before and after injection in the affected eyes, and analyzed the variance of a single repeated measurement factor. At the same time, we observed the occurrence of ocular adverse reactions and systemic complications.ResultsAfter treatment 1.2±0.4, 3.3±0.3, 6.7±1.1, 9.2±1.1, 12.2±0.6 months, the BCVA of the affected eyes were 0.488±0.296, 0.484±0.266, 0.414± 0.247, 0.411±0.244 and 0.383±0.232; CMT was 280.2±42.7, 271.0±41.4, 292.5±42.9, 276.2±40.5, 268.4±26.6 μm, respectively. Compared with before treatment, the BCVA and CMT of the all eyes increased after treatment, and the difference was statistically significant (F=30.99, 5 196.92; P＜0.000). Among 23 eyes completed a 12-month follow-up, 13 eyes (56.5%) received 2 injections, 3 eyes (13.0%) received 3 injections, and other 7 eyes (30.4%) received only 1 injection. After treatment 1.2±0.4 months, 5 patients (6 eyes) with intraocular pressure＞25 mmHg gradually returned to normal after treatment with two eye drops for lowering intraocular pressure; 1 patient (2 eyes) with intraocular pressure＞40 mmHg, the intraocular pressure gradually returned to normal after 3 kinds of eye drops for lowering intraocular pressure.ConclusionIntravitreal injection of DEX in the treatment of NIU-ME can improve the visual acuity of the affected eye and reduce CMT.