Influence of the dilution method on the intraocular duration of C₃F₈ in vitrectomy for macular hole: a randomized clinical trial

Purpose: To compare the injection of small amounts of undiluted C3F8 with the traditional gas injection in vitrectomy for macular hole treatment. Methods: This clinical trial included 26 individuals divided into two groups. Group 1 received an intravitreal injection of 0.9-1.0 mL of 100% C3F8 , and Group 2 received 15-20 mL of 20% C3F8 . Results: The median intraocular gas duration was 31 days in Group 1 and 34 in Group 2. The median letter gains in corrected distance visual acuity for the 26th postoperative week were 20 letters in Group 1 and 12.5 in Group 2. The median intraocular pressure was normal in both groups. Primary anatomical success was 11/13 in both groups. Conclusions: The use of C3F8 gas in a small undiluted volume is an alternative that slightly reduces the duration of the gas without negatively affecting the anatomical and visual response.