Diabetic%20retinopathy Treatment
Pharmacotherapy
Intravitreal Triamcinolone Acetonide (IVTA)
- Studies showed that IVTA inhibits VEGF-induced breakdown of the blood retinal barrier
- Also, studies have shown that although IVTA resulted in some reduction of macular edema, the long-term (2 yr) effect was not as good as focal laser photocoagulation
- Used in visualization during vitrectomy
- Under investigation for use in DME that persists after focal/grid laser treatment, in cases of extensive macular hard exudate deposition & adjunct to panretinal photocoagulation treatment of PDR
- Complications may include increased intraocular pressure & cataract
Intravitreal Anti-Vascular Endothelial Growth Factor (Anti-VEGF)
- Studies show that it inhibits the increase in retinal vascular permeability mediated in part by protein kinase C
- Under investigation for use in managing PDR, CSME & more advanced retinal disease eg proliferative vascular changes & neovascularization in the cases of retinal ischemia
- Bevacizumab & Ranibizumab are recombinant humanized antibodies
- Studies have shown that these drugs reduce OCT macular thickness, PDR activity & severity, & improve visual acuity (1-2 lines on a Snellen chart)
- Ranibizumab is currently being used in the treatment of DME
- Pegaptanib is an RNA aptamer that specifically binds & inhibits VEGF-165, which is responsible for neovascularization & vascular permeability, & has been shown in studies to reduce OCT macular thickness & visual loss to DME
Intravitreal Ovine Hyaluronidase
- Clinical trials have shown to be safe & modestly effective in the clearing of vitreous hemorrhage in PDR
Intravitreal Plasmin
- Studies have shown that it cleaves the vitreoretinal junction & allows less traumatic removal of the posterior hyaloid
Intravitreal Glucocorticoids
- Eg Fluocinolone
- Studies have shown that they reduce neovascularization & retinal inflammation & may restore the integrity of the blood-retina barrier by increasing tight-junction protein expression
- May cause high risk rates of increased IOP, cataract formation & endophthalmitis
Intravitreal Dexamethasone
- Studies have shown that intravitreal Dexamethasone implant improves vision & vascular leakage from DME in victrectomized patients
Ruboxistaurin
- Has been shown by studies to be associated w/ a reduction in retinal vascular leakage, as measured by vitreous fluorometry, but visual acuity was not affected