Comparison of two techniques for the decrease of perfluoropropane gas volume in the management ofretinal detachment in Thammasat hospital
Eye South East Asia
Kittichai Akrapipatkul1, Grobgarn Wichitnark1 1Department of Ophthalmology, Thammasat University, Thailand Purpose: To compare the residual gas volume of perfluoropropane C 3 F 8 after two different methods of air gas exchange procedures, namely fixed-concentration and fixed-volume, used in rhegmatogenous retinal detachment surgery. Methods: A prospective, randomized clinical trial in 56 patients whose eyes were diagnosed as rhegmatogenous retinal detachment and underwent 23-gauge pars plana
... rectomy combined with laser endophotocoagulation and air-perfluoropropane gas exchange. In 28 patients whose eyes were in fixed-concentration group, air-perfluoropropane gas exchange were performed using 20% C 3 F 8 50 cc. replacing air within eye globe and the 28 eyes in fixed-volume group, 0.8 cc. of 100% C 3 F 8 was injected into the eyes. We followed up at 1 day, 1 week, and 1 month postoperatively to measure outcomes including postoperative intraocular gas volume (in percent), anatomical retinal reattachment rate and post-operative complications such as ocular hypertension and endophthalmitis. Results: A total of 56 eyes (56 patients) with 23-gauge pars plana vitrectomy combined with laser endophotocoagulation and air-perfluoropropane gas exchange were performed in this study. The patients consisted of 34 men (60.7%) and 22 women (39.3%). Patient ages were between 33-84 years with a mean of 59.84 ± 10.4 years. The mean postoperative residual intraocular gas volume for the fixed-volume method after 1 day, 1 week, and 1 month were 81.25 ± 8.57%, 62.14 ± 12.87%, and 31.25 ± 11.52% respectively. And the mean postoperative residual intraocular gas volume for the fixed-concentration method after 1 day, 1 week, and 1 month were also 85.36 ± 10.71%, 70.36 ± 17.74% and 38.93 ± 16.18% respectively. There was no significant difference in residual intraocular gas volume between the two groups in 1 day and 1 week postoperatively. After 1 month, there was a difference of mean postoperative residual intraocular gas volume between 2 groups; 31.25 ± 11.52% for the fixed-volume method and 38.93 ± 16.18% for the fixed-concentration method (p<0.05). The anatomical retinal reattachment rates were 85.7% and 89.3% for the fixed-volume method and fixed concentration method respectively. There was no significant difference in the rates of ocular hypertension between two groups, and none of the patients developed postoperative endophthalmitis. Conclusions: Both techniques of air-perfluoropropane gas exchange in 23-gauge pars plana vitrectomy combined with laser endophotocoagulation were comparable when considering the anatomical retinal reattachment rate, though there was a smaller intraocular gas volume in fixed-volume technique when compared to fixed-concentration technique. Conflicts of interest: The authors report no confilcts of interest.