Dr. Mannarino received his Bachelor of Science magna cum laude from Manhattan College and his Doctor of Medicine from Georgetown Medical School. His ophthalmology residency was at George Washington University where he served as Chief Resident in his final year. He was Chief of Ophthalmology at Lower Bucks Hospital and founding Chief of Ophthalmology at St. Mary Medical Center.

During his career he was Adjunct Professor of Clinical Medicine at Kings College in Wilkes-Barre, PA, Clinical Preceptor for the College of Optometry at Salus University, clinical faculty for the Jefferson Bucks Residency program, clinical faculty for the Lower Bucks Hospital residency programs, former clinical faculty in the Department of Ophthalmology at Temple University School of Medicine, and Clinical Assistant Professor for the Department of Surgery at Philadelphia College of Osteopathic Medicine.

Dr. Mannarino is a Life Fellow of the American Academy of Ophthalmology.