Topical dexamethasone–cyclodextrin microparticle eye drops for uveitic macular oedema

Abstract

Cystoid macular oedema (CME) is the main cause of visual loss in patients with uveitis (Rothova 2007). The mainstay of treatment of uveitic CME is corticosteroids and to be effective, steroid needs to be given periocularly, intravitreally or systemically. Topical steroid generally is of little benefit for the treatment of posterior segment diseases. Dexamethasone eye drops containing γ-cyclodextrin-based nanoparticles, however, have recently been shown to be effectively delivered to the posterior part of the eye to treat diabetic CME (Loftsson & Stefánsson 2002; Loftsson et al. 2007; Tanito et al. 2011). Therefore, it seems tempting to examine the effect of this dexamethasone eye drop formulation for the treatment of uveitis with posterior manifestations. We have treated three patients with uveitic CME with 1.5% dexamethasone–cyclodextrin ophthalmic solution (Oculis ehf., Reykjavik, Iceland) after obtaining informed consent from each patient. A 54-year-old female with bilateral, chronic, idiopathic intermediate uveitis and CME. Left eye was previously vitrectomized. Visual acuity was reduced to 0.4 (in decimals) on both eyes. She had pronounced CME and slight vitritis (+1) in both eyes. The CME and vitritis resolved on treatment with systemic prednisone in high dose and visual acuity increased to 0.63 in both eyes. CME on the left eye, however, recurred 3 months after tapering prednisone (Fig. 1A), and visual acuity dropped down to 0.5. The patient was then treated with 1.5% dexamethasone–cyclodextrin ophthalmic solution four times daily for 1 month in the left eye. Visual acuity increased to 0.63 and the CME resolved (Fig. 1B). As dexamethasone–cyclodextrin eye drops are not available in Denmark, she then continued treatment with commercial dexamethasone eye drops, Maxidex ® (Dexamethasone 0.1%; Alcon Inc, Fort Worth, TX, USA) 4 times daily in the left eye. After 1 month, the CME in the left eye had recurred (Fig. 1C), and she was subsequently treated with periocular triamcinolone acetonide and systemic prednisone in a low dose. A 84-year-old woman with bilateral vitritis and CME. Vitritis resolved after initating systemical treatment with mycophenolate mofetil. CME was persistent in both eyes (foveal thickness 357/332 μm). Visual acuity was 0.5 in both eyes. Right eye was treated with dexamethasone–cyclodextrin eye drops two drops four times daily tapered to one drop three times daily after 3 weeks. Left eye was treated with an intravitreal dexamethasone implant (Ozurdex; Allergan, Inc., Irvine, CA, USA). After 6 weeks of treatment, visual acuity was 0.8 in the right eye and 0.63 in the left eye, and the CME had resolved in both eyes (foveal thickness 315/317 μm). A 47-year-old woman with chronic, bilateral, posterior uveitis and CME. She was treated with Ozurdex in both eyes, but the CME recurred after 3 months. The Ozurdex implantation was repeated on the left eye. The right eye was treated with dexamethasone–cyclodextrin eye drops one drop six times daily for 1 week and then four times daily for 1 week. After 2 weeks of treatment, the CME in the right eye was increased further, and the eye received a new Ozurdex implant. The present cases indicate that topical dexamethasone–cyclodextrin nanoparticle eye drops may be effective for the treatment of uveitic CME in some patients. In the first two cases, the CME was resolved after 1 month of treatment with this topical steroid formulation and recurred 1 month after treatment with conventional steroid eye drops. It therefore seems worth to explore the potential of dexamethasone–cyclodextrin nanoparticle eye drops for the treatment of uveitis with posterior manifestations as an alternative to periocular, intravitreal and systemic treatment with steroid. Periocular and intravitreal steroid carry a potential risk of ocular complications, and treatment with systemic steroid involves a considerable risk of serious systemic side-effects. Moreover, in children, the possibility of topical steroid treatment for uveitis with posterior manifestations would be of great benefit as treatment with periocular and intravitreal steroid in these patients requires a general anaesthetic prior to administration.