Abstract
Purpose: :
To compare the incidence of both sclerotomy-related iatrogenic retinal tears in 20G PPV versus 23G PPV, and the incidence of subsequent retinal detachment in both groups.
Methods: :
A retrospective, non-randomised, observational case review of 924 consecutive patients undergoing 3PPV (both 20-G and 23-G) at a single centre (Manchester Royal Eye Hospital) between August 2008 and June 2010 (23 months) (with a minimum follow-up of three months) was undertaken using an electronic vitreoretinal surgical database. The following information was collected from the electronic database: age, gender, pre-operative diagnosis, grade of surgeon, PPV technique (20-G vs. 23-G), posterior vitreous detachment (PVD) pre-existing or induced intra-operatively, whether cataract surgery was undertaken at the time of the vitrectomy (combined phacovitrectomy), the presence of sclerotomy-related retinal breaks and occurrence of iatrogenic retinal tears in the anterior (pre-equatorial) retina. Patients underwent either standard 20-G PPV or 23-G PPV (Bausch & Lomb Millenium System, Rochester, N.Y.) As routine in the department, all cases underwent an internal search with scleral indentation to identify iatrogenic anterior retinal tears and sclerotomy-associated retinal tears towards the end of the procedure, and these were treated accordingly. All surgical cases were primarily performed either by a Consultant Vitreoretinal Surgeon or a Vitreoretinal Fellow.
Results: :
Between August 2008 and June 2010 (23 month period), there were 296 23-G PPV eyes (290 patients) and 628 20-G PPV eyes (610 patients) who met the entry requirement of the study. Those undergoing 23-G PPV were significantly younger (mean years ± SD) (63 ± 17(23G) vs 67 ± 13(20G), p<0.01), less likely to be performed by a Consultant (47.3% 23G vs 60.2% 20G, P<0.01) and more likely to be a combined Phacovitrectomy (141/296 23G (47.6%) vs 246/628 20G (39.1%), p=0.02). Sclerotomy-related retinal breaks occurred in 50/628 (7.9%) of 20-G PPV and 5/296 (1.7%) of 23-G PPV (p<0.0001). Anterior (non-sclerotomy) retinal breaks occurred in 55/628 (8.7%) of 20G PPV and 18/296 (6.0%) of 23G PPV (p=0.19). In a univariate analysis, PVD induction was the only significant factor in development of an iatrogenic retinal tear, both for 23-G PPV and 20-G PPV. 7/628 20-G had redetachment (1.1%) vs 2/296 (0.67%) 23-G, p=0.73.
Conclusions: :
23-G PPV has a significantly reduced risk of causing iatrogenic sclerotomy-related retinal breaks compared to 20-G PPV, but does not result in a significant reduction in subsequent retinal redetachment.
Keywords: retinal detachment • vitreoretinal surgery