Intravitreal v. Sub-tenon Injections of Triamcinolone Acetonide for Macular Edema in Retinal Disorders

INCLUSION CRITERIA: All Participants must: Understand and sign the informed consent. Be at least 18 years of age. Have definite retinal thickening due to macular edema in the study eye, based on the clinical exam. Have retinal thickness greater than or equal to 250 microns in the central subfield on OCT. Have BCVA equal to or worse than 20/40 in the study eye. Have sufficiently clear ocular media to permit good quality retinal photographs and angiography to allow assessment of macular area according to standard clinical practice. Be able to comply with the study requirements. EXCLUSION CRITERIA: All participants must not: Have intraocular pressure greater than 25 or history suggesting glaucoma (e.g., history of the diagnosis of glaucoma, disc/nerve fiber layer defects suggestive of glaucoma) or glaucomatous visual field defects as documented by Goldmann or Humphrey perimetry taken within 6 months to qualification. 2. Be allergic to fluorescein dyes. 3. Have medical conditions that make consistent follow-up over the treatment period unlikely (e.g., stroke, severe MI, end-stage cancer, or history of chronic renal failure requiring dialysis or kidney transplant). 4. Have blood pressure greater than 180/110. 5. Be currently using or be likely to need systemic or ocular medications known to be toxic to the lens, retina, or optic nerve, such as: Deferoxamine Chloroquine/Hydroxychloroquine (Plaquenil) Tamoxifen Phenothiazines Ethambutol 6. Have used experimental therapies for the present disease in the past 3 months. 7. Have any contraindication to performing the necessary diagnostic procedures. 8. Have a history of or current acute ocular or periocular infection (including any history of ocular herpes zoster or simplex). 9. Have had any major intraocular surgical procedure within one month of enrollment. 10. Have used systemic steroids in excess of an average 20 mg daily dose for the past 3 months. 11. Have a known history of untoward complications from corticosteroid therapy, including elevated intraocular pressure in response to topical or periocular corticosteroids.