Ocular biocompatibility of polyquaternium 10 gel: functional and morphological results.

This paper deals with the characterization study of topical and intraocular biocompatibility and toxicity of cationic hydroxyethylcellulose Polyquaternium 10 (PQ10). It also evaluates the rheological properties of gels. The cytotoxicity assays were done in two cell lines: HEp-2 and VERO (human larynx epidermoid carcinoma cell and African green monkey kidney cells respectively). For the in vivo study, New Zealand albino rabbits were used. The in vitro cytotoxic activity of PQ10 shows no statistically significant differences in relation to the control of hydroxypropylmethylcellulose (HPMC) in any of the cell lines used in this study. Similarly, the signs of inflammation observed after treatment showed no significant difference between the groups of animals treated with the polymer compared to the control group. Normal histological characteristics were seen in both groups with no histological inflammatory reaction. After 1 month of the intracameral application of 2% PQ10 (treatment group) or 0.3% HPMC (control group), electroretinograms showed similar levels of a- and b-waves latencies and amplitude. In summary, PQ10 gel was well tolerated in these experiments, with proper monitoring, it could stand as a new alternative in the development of ophthalmic viscosurgical devices.

Subconjunctival dexamethasone implant for non-necrotizing scleritis.

BACKGROUND: The purpose of this study is to report the management of non-necrotizing anterior scleritis with a single-dose subconjunctival 0.7 mg dexamethasone implant (Ozurdex®, Allergan, Inc., CA, USA). Six patients with clinical diagnosis of non-necrotizing anterior scleritis (diffuse, sectorial, and nodular) were submitted to subconjunctival injection of dexamethasone implant. The injection was performed under topical anesthesia at the slit lamp. All patients reported only mild discomfort related to the procedure. Five patients had subconjunctival hemorrhage. Follow-up was performed 1, 7, 15, 30, and 45 days, and 2, 3, 4, 5, and 6 months after the procedure. Visual acuity, intraocular pressure, anterior and posterior biomicroscopy, and fundus exams were performed in each visit. RESULTS: In all patients, symptoms disappeared before day 7, and most of them were symptoms-free on day 2. The implant was visible at least up to day 45. One recurrence was noted in the 6-month follow-up in a patient with rheumatoid arthritis and non-necrotizing diffuse scleritis and was treated with oral steroids. No patient developed ocular hypertension or any kind of complications during the follow-up period, except for subconjunctival hemorrhage. CONCLUSION: Dexamethasone implant was safely and effectively used as a local therapy for non-necrotizing scleritis.