Ophthalmology is a branch of medicine and surgery that deals with the diagnosis and treatment of disorders of the eye. An ophthalmologist is a physician who specializes in ophthalmology. The credentials include a degree in medicine, followed by additional four to five years of residency training in ophthalmology. Residency training programs for ophthalmology may require a one-year internship with training in internal medicine, pediatrics, or general surgery. Additional specialty training (or fellowship) may be sought in a particular aspect of eye pathology. Ophthalmologists are allowed to prescribe medications to treat eye diseases, implement laser therapy, and perform surgery when needed. Ophthalmologists may participate in academic research on the diagnosis and treatment for eye disorders.