Gregory Haffner, M.D.
Retina Specialist and Vitreoretinal Surgeon

Retina Specialist and Vitreoretinal Surgeon
Vitreoretinal Surgeon and Uveitis Specialist
Retina Specialist and Vitreoretinal Surgeon
Vitreoretinal Surgeon and Retina Specialist
For 30 years, New England Retina Associates has been a trusted referral center for optometrists, ophthalmologists, and patients across Connecticut. With four fellowship-trained vitreoretinal surgeons and four locations across Fairfield and New Haven Counties, NERA provides the full spectrum of medical and surgical retina care. From routine monitoring to complex surgery, every patient receives individualized treatment guided by decades of specialized experience. That singular focus means every member of our team, every piece of equipment, and every clinical decision is centered on one thing: the health of your retina. With more than 2,000 five-star reviews and 30 years of care, patients and referring doctors throughout Connecticut trust NERA for conditions that demand true retinal expertise.
From intravitreal injections to advanced microsurgery, every treatment plan is tailored to your diagnosis and designed to protect your vision long-term.
View All TreatmentsFew retina practices in the region train future specialists. New England Retina Associates does, through a two-year vitreoretinal surgery fellowship program. That distinction reflects the depth of expertise our physicians bring to every patient visit. When a practice is trusted to teach the most advanced retinal procedures, the patients it serves receive that same level of precision and knowledge.

NERA is an active clinical trial site, with physicians serving as investigators in studies for macular degeneration, geographic atrophy, diabetic macular edema, and retinal vein occlusion. For patients who qualify, clinical trials can offer access to new treatment options alongside the highest standard of monitoring and follow-up care.
NERA's fellowship-trained retina specialists treat the full spectrum of retinal and vitreous conditions. Whether you have been referred by your eye doctor or are seeking care on your own, every NERA location is equipped to evaluate and treat the following conditions.
Macular & Degenerative Conditions
Diabetic & Vascular Conditions
Structural & Emergency Conditions
Inflammatory & Other Conditions
NERA provides a comprehensive range of medical and surgical retinal treatments. Every treatment plan is determined by your physician based on your specific diagnosis, the severity of your condition, your treatment history, and your overall health. Results vary by individual; your NERA physician will discuss the most appropriate approach for your situation.
Injection Therapies
Intravitreal (in-the-eye) injections are the most widely used treatment in retina medicine today. Anti-VEGF medications reduce abnormal blood vessel growth and fluid leakage in the retina and are the cornerstone of treatment for wet AMD, diabetic macular edema, and retinal vein occlusions. NERA physicians use all leading anti-VEGF agents, including:
Your doctor will recommend the most appropriate medication based on your condition and how your retina responds over time. In some cases, steroid injections — including intravitreal triamcinolone or sustained-release implants — are used to reduce inflammation and fluid in conditions such as uveitis, macular edema, and certain retinal vein occlusions.
Laser Treatments
Surgical Procedures
An accurate diagnosis is the foundation of effective retinal care. NERA uses advanced imaging technology to detect retinal disease at its earliest stages, monitor changes over time, and guide treatment decisions with precision. Most of these tests are quick, non-invasive, and completed in the office during your visit — no hospital trip required.
New England Retina Associates has provided subspecialty retinal care to Connecticut patients since 1995. The practice is led by four fellowship-trained vitreoretinal surgeons with training backgrounds at Yale, Harvard, and Johns Hopkins — each board-certified by the American Board of Ophthalmology. With more than 2,000 five-star patient reviews across four Connecticut locations, NERA serves as a major referral center for optometrists and ophthalmologists throughout Fairfield County, New Haven County, and neighboring New York. The practice also operates an on-site two-year vitreoretinal surgery fellowship program, reflecting its role as both a clinical and academic institution.
Gregory Haffner, M.D. — Partner, Vitreoretinal Surgeon
Dr. Haffner has been at NERA for more than 20 years and serves as a partner in the practice. He completed his ophthalmology residency at Yale University, where he received the Marvin Sears Award for Excellence in Clinical Ophthalmology, before completing his vitreoretinal surgery fellowship at NERA itself. Dr. Haffner is an active clinical trial investigator in age-related macular degeneration, diabetic retinopathy, and retinal vein occlusions, and has been recognized nationally as one of America's Top Ophthalmologists by the Consumers' Research Council of America.
John Huang, M.D., MBA, C.P.E. — Vitreoretinal Surgeon, Uveitis Specialist
Dr. Huang holds dual fellowship training from Harvard University — where he trained in uveitis and ocular immunology at Massachusetts Eye and Ear Infirmary — and from Johns Hopkins, where he completed his vitreoretinal surgery fellowship at the Wilmer Eye Institute. This combination is held by very few retina specialists in the region. Dr. Huang served on the Yale faculty for seven years as Associate Professor of Ophthalmology, Program Director of the residency, and Director of the Uveitis Service. He is the founder of the Connecticut Uveitis Foundation, a textbook author, and a member of the Committee for Global Burden of Disease at the World Health Organization.
Erol Verter, M.D. — Retina Specialist, Vitreoretinal Surgeon
Dr. Verter's training spans Harvard Medical School (four years of ophthalmology research at Massachusetts General Hospital), Boston University School of Medicine, and Yale-New Haven Hospital, where he completed his ophthalmology residency before returning to NERA for his vitreoretinal surgery fellowship. He serves as a Clinical Instructor of Ophthalmology at Yale School of Medicine and as Chair of Ophthalmology at St. Vincent's Medical Center, and holds hospital appointments at Yale New Haven, Bridgeport, Stamford, Greenwich, and Saint Vincent hospitals. Dr. Verter conducted Yale Diabetes Research Center-funded research on contrast sensitivity as an early detection tool for diabetic retinopathy, and volunteers at the Dana Eye Clinic at Yale New Haven Health, providing care for uninsured patients throughout the community.
John Siano, D.O. — Retina Specialist, Vitreoretinal Surgeon
Dr. Siano completed his ophthalmology residency at Nassau University Medical Center, where he served as Chief Resident, before completing his vitreoretinal surgery fellowship at NERA. His clinical focus includes macular degeneration, geographic atrophy, diabetic retinopathy, diabetic macular edema, retinal vein occlusion, macular hole, retinal detachment, and retinal complications following cataract surgery. Dr. Siano is actively involved in clinical trials for AMD and geographic atrophy, giving eligible patients access to emerging therapies before they are widely available. He is currently accepting new patients at all NERA locations.