Safety and effectiveness of intravitreal dexamethasone implant in patients with ocular toxocariasis

Aims To evaluate the safety and effectiveness of intravitreal dexamethasone (DEX) implant in patients with active uveitis due to ocular toxocariasis (OT). Methods Seventy-eight patients with OT were recruited in this retrospective study, including 51 patients in DEX group treated with intravitreal DEX implant and 27 patients in control group without intervention. The reduction of vitreous haze scores (VHS), the best-corrected visual acuity (BCVA) changes, intraocular pressure (IOP) and cataract progression and formation were recorded at baseline (V0), 1 (V1), 3 (V3) and 6 months (V6) after treatment in DEX group, and V0 and V6 in control group. Results There was no change in VHS and BCVA in control group between V0 and V6. Better VHS (p=0.001) and BCVA (p=0.022) was achieved in DEX group; the rate of VHS=0 was 0%, 67.4%, 42.9% and 44.9% at V0, V1, V3 and V6, respectively (p＜0.001), and the mean BCVA was improved from logMAR 1.5±0.9 to 1.2±0.9 at V1, 1.4±1.0 at V3 and 1.4±1.2 at V6. A favourable BCVA at V1 was associated with older age (p=0.038) and uninvolved macula (p=0.000) in DEX group. No significant difference in IOP elevation ≥10 mm Hg, cataract progression and formation between groups. More eyes needed retinal surgery in control group (p<0.001). Conclusions This was the first study to investigate use of intravitreal DEX implant in OT patients, which can efficiently reduce ocular inflammation and improve BCVA in macular uninvolved patients.