Errol Grannum is an Ophthalmologist in Brownsville, Texas. Dr. Grannum has been practicing medicine for over 35 years is highly rated in 1 condition, according to our data. His top areas of expertise are Glaucoma, Cataract, Ocular Hypertension (OHT), and Retinal Vein Occlusion. Dr. Grannum is currently accepting new patients.