Received: 22 August 2000 Revised: 7 June 2001 Accepted: 7 June 2001 Published online: 25 August 2001 © Springer-Verlag 2001 Abstract Background: Our aim was to evaluate the effect of an intraoperative single dose of retino- ic acid (RA) or mitomycin C (MMC) in preventing posterior capsule opacification (PCO). Methods: Twenty-seven rabbits were divided randomly into three groups. RA (250 μg/ml) and MMC (0.04 mg/ml) were given 0.1 ml by hydrosection and 0.9 ml into the capsular bag after phacoemulsi- fication. The third group served as a control group. Three months after intervention PCO was graded clinically. Furthermore, proliferation of lens epithelial cells was evaluated histologically. Results: Two eyes developed corne- al edema in the MMC group. On clinical assessment, RA and MMC were significantly effective in pre- venting PCO compared with con- trols (P<0.005). On histological analysis, there was significantly reduced proliferative activity on posterior capsules in the treat- ment groups, in contrast to multi- layer cells in the control group. Conclusion: Intraoperative single- dose administration of RA and MMC significantly prevented the development of PCO in rabbit eyes. The optimal biocompatible dosage must be carefully determined by further investigation. Graefe's Arch Clin Exp Ophthalmol (2001) 239:693–697 DOI 10.1007/s004170100329 LABORATORY INVESTIGATION Ümit Übeyt I ˙ nan Faruk Öztürk Süleyman Kaynak Süleyman Sami I ˙ lker Erdener Özer Cenap Güler Prevention of posterior capsule opacification by retinoic acid and mitomycin Introduction Posterior capsule opacification (PCO) is the most com- monly encountered complication after extracapsular cat- aract extraction (ECCE) and posterior chamber intraocu- lar lens implantation (PC-IOL) [1]. The proliferation and migration of residual lens epithelial cells (LECs) cause this condition [5, 7, 8, 16, 20, 21, 24, 33]. The incidence of PCO 3–5 years after surgery is 8–50% in adults [22, 23, 30,34] but 95% in children [14, 17]. Opacification Presented as a poster at the 12th Congress of the European Society of Ophthalmology (SOE), June 27 to July 1 1999, Stockholm, Sweden No financial and proprietary interests Ü.Ü. I ˙ nan ( ✉ ) Dumlupinar Mah. Turabi Cad., Tütüncü Apt. B Blok 4/7, 03200 Afyon, Turkey e-mail: uuinan@superonline.com Tel.: +90-272-2140600 Fax: +90-272-2172029 or + 90-272-2139404 Ü.Ü. I ˙ nan · F. Öztürk Department of Ophthalmology, School of Medicine, Kocatepe University, Afyon, Turkey S. Kaynak Department of Ophthalmology, School of Medicine, Dokuz Eylül University, Izmir, Turkey S.S. I ˙ lker · C. Güler Department of Ophthalmology, School of Medicine, Celal Bayar University, Manisa, Turkey E. Özer Department of Pathology, School of Medicine, Dokuz Eylül University, Izmir, Turkey