A 48-year-old woman with type 1 diabetes mellitus for 15 years presents with sudden onset of floaters and blurred vision in the left eye. She has no pain or photophobia. Her HbA1c is 8.1%. On examination, visual acuity is hand movements in the left eye. Dilated fundoscopy reveals extensive dot-blot and flame-shaped hemorrhages, venous beading, multiple areas of cotton-wool spots, and prominent intraretinal microvascular abnormalities (IRMA). No neovascularization is visible. B-scan ultrasonography shows vitreous hemorrhage. What is the most appropriate next step in management?