John I. Loewenstein, M.D.

Associate Clinical Chief of Ophthalmology



Macular Degeneration

Board Certification

  • Ophthalmology

800 Huntington Ave.
Boston, MA 02115
Phone: 617-573-3202



A practicing ophthalmologist for almost 40 years, Dr. John Loewenstein serves as Associate Clinical Chief and provides clinical care through the Retina Service at Mass. Eye and Ear. After earning his medical degree at the State University of New York at Buffalo School of Medicine, Dr. Loewenstein completed his ophthalmology residency at Boston University and a vitreoretinal disease fellowship through Boston University's affiliated hospitals.

His clinical practice focuses on diseases of the retina and vitreous, especially diabetic retinopathy, macular degeneration, and retinal degenerations. He worked with the Boston Retinal Implant Project to develop the surgical techniques for implantation of an experimental retinal prosthesis and performed the first surgical procedures to place a microfabricated electrode array on the retinal surface.

The recipient of numerous teaching awards, including the 1996, 2001, and 2015 HMS Teacher of the Year awards, Dr. Loewenstein plays a vital role in ophthalmic education. For more than a decade, he served as Residency Program Director, a role in which he led multiple curricular initiatives for the HMS Ophthalmology Residency Training Program. For instance, in collaboration with Carolyn Kloek, MD, he developed and implemented a progressive, step-wise surgical curriculum that improved the learning experience for trainees. He also worked with Demetrios Vavvas, MD, PhD to establish the first national vitrectomy course for first-year vitreoretinal fellows, which fills to capacity each year. Today, Dr. Loewenstein serves as Associate Chief for Ophthalmic Education at Mass. Eye and Ear, as well as Vice Chair for Education in Harvard Ophthalmology. 

Dr. Loewenstein also conducts research in surgical education, leading the development of computer based cognitive simulations to teach cataract surgery and screening for retinopathy of prematurity.

Clinical Interests

Diseases of the retina and vitreous, including diabetic retinopathy, macular degeneration and other macular diseases, retinal degenerations, medical retina

Research Interests

Retina and vitreous disorders, surgical education


For a full publication list, please see his CV.

Evaluation of the virtual mentor cataract training program. Henderson BA, Kim JY, Golnik KC, Oetting TA, Lee AG, Volpe NJ, Aaron M, Uhler TA, Arnold A, Dunn JP, Prajna NV, Lane AM, Loewenstein JI. Ophthalmology. 2010 Feb; 117 (2): 253-8.

High-resolution optical coherence tomography findings in solar maculopathy and the differential diagnosis of outer retinal holes. Comander J, Gardiner M, Loewenstein J. Am J Ophthalmol. 2011 Sep; 152(3): 413-419.e6.

Conversion to aflibercept for chronic refractory or recurrent neovascular age-realted macular degeneration. Yonekawa Y, Andreoli C, Miller JB, Loewenstein JI, Sobrin L, Eliott D, Vavvas DG, Kim IK. Am J Ophthalmol. 2013 Jul;156(1):29-35.

Concordance of antiretinal antibody testing results between laboratories in autoimmune retinopathy. Faez S, Loewenstein J, Sobrin L. JAMA Ophthalmol. 2013 Jan;131(1):113-5.

Diagnostic testing and disease monitoring in birdshot chorioretinopathy. Comander J, Loewenstein J, Sobrin L. Semin Ophthalmol. 2011 Jul-Sep;26(4-5):329-36.

View a list of publications on>>

To learn more about Dr. Loewenstein, read his "Meet a Specialist" profile here.



  • Massachusetts Institute of Technology, BS
  • State University of New York at Buffalo, M.D.


  • Ophthalmology, Boston University


  • Vitreoretinal Disease, Boston University, Affiliated Hospitals