IDENTIFICATION OF ANASTOMOSIS BETWEEN THE CENTRAL RETINAL ARTERY AND THE CENTRAL RETINAL VEIN IN A CASE OF CENTRAL RETINAL VEIN OCCLUSION DUE TO ARTERIOVENOUS MALFORMATION Joe ¨l Hanhart, MD,* Marc Labetoulle, MD, PHD,† Fre ´de ´ric Azan, MD,‡ Jose ´-Alain Sahel, MD,*§ Michel Paques, MD, PHD*§ Purpose: To report the identification of an arteriovenous anastomosis over the optic nerve head in a case of arteriovenous malformation. Case Report: Dynamic scanning laser angiography was performed in a 12 year old girl with a severe arteriovenous malformation complicated by central retinal vein occlusion. Results: The presence of an arteriovenous anastomosis between the central retinal artery and vein was identified. This anastomosis later regressed completely. Conclusions: An arteriovenous anastomosis between central vessels within the optic nerve may be a cause of central retinal vein occlusion. Spontaneous regression of the anastomoses may lead to improvement of fundus features. RETINAL CASES & BRIEF REPORTS 2:322–324, 2008 From the Ophthalmology Departments of the *Fon- dation Ophtalmologique A. de Rothschild, the †Hopi- tal de Bice ˆtre, the ‡Hotel–Dieu, Assistance Publique– Hopitaux de Paris, and §Centre d’ Investigation Clinique 503, INSERM, Paris, France. W e describe a case of central retinal vein occlu- sion (CRVO) associated with an arteriovenous malformation in a 12-year-old girl in whom high- speed videoangiography identified the presence of an arteriovenous anastomosis between the central retinal artery and the central retinal vein. Case Report A 12-year-old girl was referred to us with an 8-month history of CRVO in the left eye. She was otherwise healthy and had no personal or family history of thrombosis. She denied a history of head trauma. She had been treated elsewhere for vitreous hemor- rhage by pars plana vitrectomy, endophotocoagulation, and triam- cinolone acetonide injection. At the time of the first examination in our department, visual acuity was 20/20 in the right eye and finger counting in the left eye. Intraocular pressure was 12 mmHg in both eyes. Fundus examination revealed normal findings for the right eye and evidence of chronic CRVO in the left eye that was associated with disseminated laser scars and central macular fibro- sis. An enlarged central retinal artery, a vascular loop (Fig. 1, left), and multiple vessels directed toward a peripheral arteriovenous anastomosis (Fig. 1, right) led to a presumed diagnosis of arterio- venous malformation. Early-phase frames of high-speed indocya- nine green angiography with a scanning laser ophthalmoscope showed early filling of the vascular loop over the optic nerve head, suggesting it was an arteriovenous anastomosis between the central retinal artery and the central retinal vein (Fig. 2 and video). Doppler pulsed echography did not demonstrate increased flow velocity in the affected optic nerve as compared with the other side. Medical workup, including brain magnetic resonance imaging with angiography, did not reveal any associated lesions. Examination 3 months later showed improvement of fundus features together with disappearance of the arteriovenous anastomosis (Fig. 3). Visual acuity remained counting fingers. The authors have no proprietary interest related to this report. Reprint requests: Michel Paques, MD, PhD, Department of Ophthalmology, Fondation Ophtalmologique A. de Rothschild, 25 rue Manin, 75019 Paris, France; e-mail: michel.paques@laposte.net 322