Diabetic Macular Edema with or without Epiretinal Membrane

The standard treatment for diabetic macular edema (DME) is medical treatment. The most widely performed modality is antivascular endothelial growth factor (anti-VEGF) injection alone or in combination with intravitreal or posterior subtenon steroids and/or lasers, either in a grid or focal pattern with regular or micropulse regimens (Schmidt-Erfurth et al., Ophthalmologica 237:185–222, 2017). Vitrectomy with membrane peeling for macular edema associated with a taut posterior hyaloid has been advocated and has become a consensus among retinal surgeons (Lewis et al., Ophthalmology 99:753–759, 1992; Harbor et al., Am J Ophthalmol 121:405–1413, 1996; Pendergast et al., Am J Ophthalmol 130:178–186, 2000; Kimura et al., Retina 25:454–461, 2005). Surgical treatment for intractable DME without visible epiretinal membranes (ERMs) on optical coherence tomography (OCT) has been debated (Kimura et al., Retina 25:454–461, 2005; Rosenblatt et al., Graefes Arch Clin Exp Ophthalmol 243:20–25, 2005; Yamamoto et al., Am J Ophthalmol 135:14–19, 2003; Ghassemi et al., J Curr Ophthalmol 28:199–205, 2016). The pathophysiology of ME caused by the vitreous and the indications and timing of surgery for eyes with DME unresponsive to anti-VEGF or steroids will be briefly discussed in this chapter.