comparison of intraoperative retinal break formation during standard 20-gauge and 23-gauge sutureless vitrectomy systems

purpose : the aim of this study was to compare the rate and location of intraoperatively induced retinal breaks between two techniques of standard 20-gauge vitrectomy and transconjunctival 23-gauge using trocar/cannula methods : in this prospective comparative case series patients having attached retina before surgery who were operated for different vitreoretinal or macular conditions by standard 20-gauge trans-pars plana vitrectomy (20g) were compared with another group of patients who were operated by 23-gauge using trocar/cannula system. the peripheral retina was examined before surgery and by the end of surgery using indirect ophthalmoscope and scleral depression. the rate of iatrogenic break formation, number and type of breaks and location of breaks were compared between the two groups. results : a total of 115 vitrectomies were studied. fifty five vitrectomies were done by transconjunctival micro-incision vitrectomy systems (mivs) and 60 were performed by standard 20g system. the overall rate of iatrogenic break formation was two (3.6%) and seven (11.7%) for 23-gauge and 20-gauge system, respectively. eleven breaks in 20g group were either dialysis behind or tears within one clock hour from the sclerotomy site, while the two patients in 23-gauge group had tears away from the sclerotomy site (p<0.05). no patient in the 23-gauge group showed iatrogenic dialysis. conclusion : twenty-three gauge vitrectomy may have the potential benefit of lower complication in terms of sclerotomy related breaks and retinal dialysis formation. this benefit should be weighed against the limitations and other potential complications of this technique. further studies are required to assess their safety and other complications of these systems.     iranian journal of ophthalmology 201224(3):27-32 © 2012 by the iranian society of ophthalmology