Abstract
Purpose: :
To compare the speed of visual recovery and visual outcome of 25 gauge (25gPPV) versus 20 gauge pars plana vitrectomy (20gPPV) surgery for epiretinal membrane (ERM) removal
Design: :
Retrospective non–randomized comparative study of all ERM surgery performed by single surgeon (JIL) from July 2000 to January 2005.
Methods: :
Surgical logs were reviewed for cases of ERM. Standard 3 port PPV and membrane peel without internal limiting membrane peel and without the use of adjuvant stains was done on all patients, using a combination of bent MVR, microsurgical pic, and micosurgical forceps, using either 20g or 25g instruments, without the use of intraoperative staining adjuvants.
Results: :
A total 31 eyes of 29 patients underwent ERM removal, 10 patients (11 eyes) underwent 20 gauge (35 %), 17 patients (18 eyes) 25 gauge (58%) and 2 patients had 25 gauge with single 20 gauge sclerotomy (1%). Right eye was operative eye in 16, left eye in 13 patients. Their ages ranged from 9–83, mean and median of 62 and 69, respectively. Preoperative visual acuities ranged from HM to 20/50; with a median of 20/200. Best postoperative visual acuity was reached in less than 2 weeks in 3/20 (15%) eyes in 25Gppv versus none of 20gPPV (p=0.17), 5/20 (25%) of 25gPPV in 45 days or less versus 2/11 (18%) 20gPPV(P=0.7). Postoperatively, visual acuity improved in 25/31 eyes (9 eyes after 20gPPV, 16 eyes after 25gPPV), stayed unchanged in 4/31 eyes (13%, 3 eyes after 25gPPV, and 1 eye after 20gPPV), and worsened in 2/31 eyes (both recurrent ERM, 1 eye each 20g –and 25gPPV).
Median postoperative vision was 20/40. Final visual acuity of 20/40 or better was achieved in 5/11 eyes after 20gPPV, and 11/20 eyes after 25gPPV (p=0.6).
Follow–up ranged from 2 months to 51 months (9–51 months for 20G, 1–36 for 25G) with a mean and median of 16 (25 for 20G and 15 months for 25G) and 14 months ( 25 for 20G and 26 months for 20G) respectively.
Conclusions: :
Within the limits of a small retrospective review, we found that surgical removal of ERM can be feasibly and safely performed using 25gPPV. There was a trend for more patients undergoing 20g PPV to require cataract surgery (p=0.26). Although the final visual outcome was comparable, we observed that 15 % of patients undergoing 25gPPV reach their best postoperative visual acuity within 2 weeks or less (p=0.17).
Keywords: macula/fovea • vitreoretinal surgery