Drugs causing macular toxicity when given intiavitreally-
Ref:comprehensive ophthalmology AK Khurana 4th edition page no :152 Gentamycin is 4 times more retinotoxic (causes macular infarction) than amikacin. Preferably the aminoglycosides should be avoided. 
Gentamycin
Vancomycin
Dexamethasone
Ceftazidime
Vitreous and retina