Korean J Ophthalmol Vol.22, No.4, 2008 Case 2: A 61-year-old man with diabetes mellitus, hypertension and NVG (LE) had undergone AGV implantation (LE) 19 months prior to its explantation. At 4 months postoperative, exposure of the AGV tube was noted. Except for mild hyperemia around the exposed tube, no significant inflammatory sign was noted in the anterior chamber or around the tube. IOP stayed under 20 mm Hg. However, the cataract of his left eye worsened enough to preclude a view of the fundus. Nineteen months after the AGV implantation, phacoemulsification, posterior chamber lens (PCL) implantation, AGV explantation and trabeculectomy with an intraoperative application of Mitomycin-C (0.2 mg/ml for 2 minutes) were performed concurrently on his left eye. The AGV was explanted by the method described previously. The IOP ranged from 9 to 23 mmHg during the early postoperative 3 months. At the latest follow-up at postoperative 23 months, the IOP was 13 mm Hg and no fistula-related complication was found (Fig. 3). Case 3: A 56-year-old diabetic man who had undergone pars plana vitrectomy, phacoemulsification, PCL implantation and AGV implantation (LE) complained of ocular pain at postoperative 2 years. Hypopyon and exposure of AGV tube were noted. The patient was immediately treated with a topical fluoroquinolone (ciprofloxacin) hourly for presumed endophthalmitis. The next day the AGV was explanted using the aforementioned method. With topical antibiotics, the anterior chamber reaction resolved completely. No cultures yielded any organisms. However, at the postoperative day one, the IOP went up to the 40s. Diode laser transscleral cyclophotocoagulation was performed to control IOP. At postoperative 12 months, and the IOP was in the late 10s without any complications (Fig. 4). Case 4: A 17-year-old man, who had undergone trabeculotomy, trabeculectomy and AGV implantation (LE) for congenital glaucoma, underwent a second AGV implantation (LE). Two months postoperatively, the tube of the second AGV was noted exposed. Explantation of the second AGV was performed using the pericardial plug in the aforementioned manner. The next day after the surgery, the IOP rose to 28 mmHg. Two hypotensive medications Fig. 3. (A) Slit-lamp photo shows the tube exposed externally through overlying conjunctival erosion. (B) Slit-lamp photo shows the pericardium plugged (black arrow) in the corneal fistula at 12 months after AGV explantation. Fig. 4. (A) Slit-lamp photo shows the tube exposed externally through the overlying conjunctival erosion. Hypopyon is also noted. (B) Slit-lamp photo shows the pericardium plugged (black arrow) in the corneal fistula at 7 months after AGV explantation. 270