L’iridoschisis, une forme particulière d’atrophie irienne

Iridoschisis is a rare degenerative disease characterized by the separation of the anterior iris stroma from the posterior layer. The anterior layer splits into strands, and the free ends float freely in the anterior chamber. We report the case of a 57-year-old man, in whom we incidentally discovered isolated unilateral iris atrophy. The patient had no history of the common causes of atrophy (herpes, pigment dispersion, ocular trauma, etc.). During follow-up, the atrophy gradually worsened, with an increase in the number and bilaterality of the lesions. Ultrasound biomicroscopy (UBM) and optical coherence tomography (OCT) of anterior chamber showed thinning of the anterior iris and cleavage of the iris into two layers, an imaging result which, to our knowledge, has not yet been reported in the literature. Familiarity with iridoschisis is important, due to its frequent association with glaucoma, so that appropriate screening can be carried out at the time of diagnosis and on follow-up. (C) 2012 Elsevier Masson SAS. All rights reserved

Migration en chambre antérieure de l’implant intravitréen de dexaméthasone Ozurdex® chez le pseudophake : à propos de trois cas

Introduction. - Intravitreal implantation of Ozurdex (R) (Allergan Inc., Irvine, CA, USA) is being used widely for the treatment of macular edema secondary to retinal vein occlusion and in the setting of non-infectious posterior uveitis. We describe a complication little reported in the literature until now: migration of the dexamethasone implant into the anterior chamber. Patients and methods. - We report three cases of migration in two pseudophakic patients with iris claw lenses (on the anterior and posterior aspects of the iris) and in one pseudophakic patient with a posterior chamber IOL and zonular rupture. Discussion. - The risk of anterior chamber migration of the Ozurdex (R) implant is increased in cases of prior vitrectomy (three cases), prone positioning and dilation of the pupil (mydriasis). Clinical tolerability of the implant in the anterior chamber is poor in all cases, with diffuse corneal edema. Endothelial cell loss occurs, as demonstrated by specular microscopy performed in two of our patients. Removal or repositioning of the Ozurdex (R) implant into the posterior segment must be performed without delay because of the risk of endothelial toxicity. Conclusion. - Patients without perfect zonular/posterior capsular integrity present a high risk of anterior chamber migration of the Ozurdex (R) implant. In such cases, anti-VEGF therapies should be discussed as an alternative. (C) 2012 Elsevier Masson SAS. All rights reserved