Background: During the remove of oil from the silicone oil-filled eye after vitrectomy, perfusion fluid is often mistakenly aspirated when mechanical force is used to remove the oil. This leads to a sudden sharp drop in intraocular pressure and collapse of the eyeball, which may cause complications. The aspiration of perfusion fluid can be detected when the oil is removed manually, and the force of the hand and location of the aspiration can be adjusted to remove the silicone oil instead. In this study, we assessed the efficacy and safety of a manual 23-gauge (23G) silicone oil remove method and confirmed that this is a feasible, highly efficient, safe, simple and economical way to remove oil. Methods:We recruited 130 patients (130 affected eyes) 3-6 months after they had undergone vitrectomy and light silicone oil tamponade at our hospital. The patients/eyes were randomly divided into two groups (manual or vitrectomy system), with 65 eyes in each group. All eyes in both groups underwent 23G oil remove by the same physician. The following aspects of the two groups were compared: (I) oil remove duration; (II) average intraocular pressure at 1 day, 1 week and 1 month after the procedure; and (III) postoperative complications, such as retinal redetachment, silicone oil residue, massive suprachoroidal hemorrhage and choroid detachment. Results:The average oil remove durations of the manual group and the vitrectomy system group were 5.92±1.34 and 8.87±1.68 min, respectively (P<0.05); the duration for the manual group was significantly shorter than that for the vitrectomy system group (t=11.07, P=0). The average intraocular pressures at 1 day, 1 week and 1 month after operation of the manual group were 10.2±2.7, 15.2±3.5 and 17.2±3.1 mmHg, respectively, and those of the vitrectomy system group were 9.8±2.4, 15.5±3.1 and 16.8±3.4 mmHg, respectively; the differences between the two groups were not statistically significant at any time point (t=0.892, P=0.374 at 1 day; t=0.517, P=0.606 at 1 week; and t=0.701, P=0.485 at 1 month). The difference in the incidence of postoperative complications, including retinal redetachment, silicone oil residue, massive suprachoroidal hemorrhage and choroid detachment, between the two groups was statistically significant (χ 2 =4.2787, P=0.0386). None of the affected eyes were complicated with transient intraocular hypotension, vitreous hemorrhage or endophthalmitis. Conclusions:The manual 23G silicone oil remove method is highly efficient, safe, simple and economical and can be used conveniently and clinically by the majority of medical institutions.