Korean J Ophthalmol Vol.20, No.4, 2006 Fig. 1. Diffuse stromal edema (white shaded area) involving the pupil from the 12 to 4 o’clock position. anterior chamber was irrigated with 100ml of a balanced salt solution (CYTOSOL OPHTHALMICSTM) for one minute. On postoperative day one, the patient complained of blurred vision and foreign body sensations. Severe corneal edema and Descemet’s membrane folds invading the visual axis were seen extending from the 12 to 4 o’clock position (Fig. 1). Inflammatory cells and flares were 3+ in the anterior chamber. Best-corrected visual acuity was 0.2, and intra- ocular pressure was 18 mmHg by noncontact tonometer. Postoperatively, CravitⓇ (levofloxacin 0.5%, Santen, Osaka, Japan), 1% prednisolone, and 5% NaCl were administered every two hours. Oral prednisolone (20 mg) and ofloxacin (300 mg) were used as well. A pressure patch with ofloxacin and dexamethasone ointment was administered during sleep. The corneal edema persisted until postoperative day three, and the best-corrected visual acuity decreased to 0.15. The vision improved to 0.4 after two weeks, but the corneal edema persisted without improvement. The patient continued with the original and medications and dosages. On the third postoperative week, the best-corrected visual acuity stabilized at 0.4, and the corneal edema began to resolve. The visual acuity continued to improve to 0.7, and the corneal edema finally resolved four weeks postoperatively. However, the linear Descemet’s membrane folds persisted up to post- operative week 16 (Fig. 2, 3). At the same site of the Descemet’s membrane fold, corresponding endothelial damage was also observed, manifesting as a definite dark acelluar area on specular microscopy (Fig. 4). The preopera- tive endothelial cell density on specular microscopy was 2717 cells/mm2 and the mean cell size was 368 µm2. At postoperative month three, the mean cell size was 424 µm2 2 and endothelial cell density had decreased to 2358 cells/mm . No other changes were observed after that, and the best-corrected visual acuity improved to 0.8 at postoperative month four. Discussion Almost every ocular drug can be potentially toxic to the corneal endothelium, and the risk of endothelial toxicity is increased when used in the anterior chamber because of its direct contact to the endothelium. Corneal endothelium is vulnerable even to osmotic change or pH change of the irrigating fluid, and is easily damaged by electrolyte imbalance. Moreover, permanent endothelial dysfunction, cystoid macular edema, pupil dilation, and glaucoma due to destruction of Fig. 2. Note the whitish Descemet’s membrane folds (A) and schematic diagram (B). 242