Purpose: We conducted 25- gauge (25G) transconjunctival vitrectomy to treat patients with various ocular diseases, and examined the possibility of expanding the indications for this system through combined use with 20G devices when needed. Methods: The records of 167 patients (169 eyes) who underwent vitrectomy in our hospital between April and June 2004 were studied. Vitrectomy had been conducted using the 20G or 25G transconjunctival vitrectomy system. Results: In 7 of the 169 eyes (4% ), the 20G system was initially selected. Vitrectomy could be performed using the 25G system alone in 150 eyes (89% ), while 20G devices were used in combination with the 25G system in 12 (7% ). None of the 25G scleral wounds were sutured, while all the 20G scleral wounds were sutured at the completion of surgery. Low intraocular tension was noted in 15 of 162 eyes (9% ), but all these eyes recovered within 2 to 4 days. In two eyes with macular hole, retinal detachment occurred, but reattachment was achieved after reoperation. No extensive vitreoretinal hemorrhage or postoperative infection was observed. Conclusions: By combining the use of 20G devices, indications for the 25G system can be expanded. However, postoperative low ocular tension must be addressed by carefully considering surgical indications and prevention measures. Methods: We conducted 25-gauge (25G) transconjunctival vitrectomy to treat patients with various ocular diseases, and examined the possibility of expanding the indications for this system through combined use with 20G devices when needed. Methods: The records of 167 patients (169 eyes ) who underwent vitrectomy in our hospital between April and June 2004 were studied. Vitrectomy had been conducted using the 20G or 25G transconjunctival vitrectomy system. Results: In 7 of the 169 eyes (4%), the 20G system was initially selected. Vitrectomy could All of 20G devices were used in combination with the 25G system in 12 (7%). None of the 25G scleral wounds were sutured, while all the 20G scleral wounds were sutured at the completion of surgery. Low intraocular tension was noted in 15 of 162 eyes (9%), but all of these eyes recovered within 2 to 4 days. In two eyes with macular hole, retinal detachment occurred but but reattachment was ac However, postoperative low ocular tension must be addressed by carefully considered surgical indications and prevention measures .