A solution of perfluorohexyloctane and silicone oil with a specific gravity of 1.06 g/cm(3) (Densiron-68) has similar properties as conventional silicone oil (SO) in terms of the shape of the bubble and its ability to act as an internal tamponade agent. We conducted a case-control study to compare the postoperative intraocular pressure (IOP) in patients treated with Densiron-68 with those treated with SO.Seventy-one eyes of 71 patients and 57 eyes of 57 patients who had received Densiron-68 and SO, respectively, were included in our study. Both groups were found to have matched for their preoperative comorbidities (diabetes, glaucoma, phakic status, and refractive errors). IOP at first day, between seventh and fourteenth day, and at 4 week postoperatively was recorded.The mean IOP was higher in patients treated with Densiron-68 at day 1 and between seventh and fourteenth day postoperatively (P=0.05 and 0.01, respectively). By the 4th week, the IOP difference between the two groups was insignificant (P=0.17). The difference in the two groups could still be clinically significant and the raised IOP in Densiron-68 group was more difficult to treat in some cases.On day 1, nine eyes (12.7%) in the Densiron-68 group and two eyes (3.5%) in the SO group had IOP greater than 30 mmHg. At 4 weeks, IOP of more than 30 mmHg was seen in nine eyes (12.7%) in the Densiron-68-treated group and in one eye (1.8%) in the SO group.The use of Densiron-68 was associated with a higher IOP in the early postoperative period when compared with SO.