Preoperative Factors for Poor Vision After Vitrectomy in Severe Proliferative Diabetic Retinopathy

Various pre- and postoperative factors associated with a poor visual outcome, including poor preoperative visual acuity (VA), older age, iris neovascularization, a history of lensectomy, the creation of iatrogenic breaks, and elevated intraocular pressure, have been reported in the literature (Thompson et al., Arch Ophthalmol, 105(4): 497–502, https://doi.org/10.1001/archopht.1987.01060040067035 , 1987; Thompson et al., Ophthalmology, 93(3): 290–5, https://doi.org/10.1016/s0161-6420(86)33741-2 , 1986; La Heij et al., Graefes Arch Clin Exp Ophthalmol, 242(3): 210–7. https://doi.org/10.1007/s00417-003-0815-5 , 2004. Newman, Eye (Lond), 24(3): 441–9, https://doi.org/10.1038/eye.2009.325 , 2010. Yorston et al., Br J Ophthalmol, 92(3): 365–8, https://doi.org/10.1136/bjo.2007.124495 , 2008). However, few studies have specifically focused on the preoperative systemic and local factors that may be related to extremely poor visual function despite anatomical success and an uneventful postoperative course. The identification of these factors may be useful for predicting poor functional outcome and avoiding unnecessary surgical intervention. In this chapter, risk factors associated with anatomical success but functional failure after DV will be discussed.