Mark Pennesi M.D., Ph.D.

Photo of Mark Pennesi, M.D., Ph.D.
Faculty profile
  • Division Chief, Ophthalmic Genetics

Associate Professor of Ophthalmology School of Medicine

Accepting new patients

4.8 out of 5 (165 Ratings, 47 Comments)


  • Ophthalmology

Special focus on

  • Retinal Dystrophies Congenital/Genetic Disease


  • B.S., University of Pennsylvania, Philadelphia Pennsylvania 1997
  • Ph.D., Baylor College of Medicine, Houston Texas 2003
  • M.D., Baylor College of Medicine, Houston Texas 2004
  • Residency:

    • Transitional year, Scripps Mercy Hospital, San Diego, California, 2005
  • Fellowship:

    • Ophthalmic genetics fellowship, Casey Eye Institute, Oregon Health & Science University, 2009
  • Certifications:

    • American Board of Ophthalmology, 2010


Dr. Pennesi was born in Mount Kisco, New York, and moved to Dallas, Texas at a young age. For college, he moved to the east coast and attended the University of Pennsylvania for his undergraduate studies. There he graduated summa cum laude with a BS in biomedical engineering and was awarded the Herman P. Schwann award in bioengineering for exemplary scholarship.

Dr. Pennesi's interest in degenerative retinal disorders began shortly after his first year in college, when he spent a summer working at the Retina Foundation of the Southwest. He worked under the supervision of Dr. David Birch and saw patients with retinal degenerations such as retinitis pigmentosa as well as studying animal models of this disease.

After college, Dr. Pennesi completed a combined M.D./Ph.D. at Baylor College of Medicine in Houston, Texas. He performed his graduate Ph.D. work in the Department of Neuroscience in the lab of Dr. Samuel Wu. His thesis work focused on identifying new animal models of retinal degeneration. He received numerous awards while in graduate school, including the John J. Trentin Award for earning the highest GPA in his class and the BRASS scholarship for playing an active role in community service.

For his residency training, Dr. Pennesi spent his internship year in San Diego at Scripps Mercy Hospital, followed by his ophthalmology residency at the University of California, San Francisco. During residency he was awarded the Hogan/Garcia award for the best resident research project. After residency he completed an ophthalmic genetics fellowship under the tutelage of Dr. Richard Weleber.

Dr. Pennesi joined the faculty of Casey Eye Institute and is now an Associate Professor in Ophthalmic Genetics and as the chief of the Ophthalmic Genetics Division.

Both Research to Prevent Blindness and the Foundation Fighting Blindness have recognized Dr. Pennesi with career development awards to support his ambition to conduct transitional research that will bring treatments for diseases such as retinitis pigmentosa from the laboratory to the clinic. Additionally, he is the recipient of the 2011 ARVO/Alcon Early Clinician Scientist, the Alcon Young investigator Award in 2014, and the Casey Eye Institute Resident teach award. His research focuses on developing novel treatments for inherited retinal diseases. He is currently exploring the potential of a new class of drugs to up regulate protective growth factors in the retina.

Read more


  • English

Patient Ratings

4.8 out of 5 (165 Ratings, 47 Comments)

The patient ratings score is an average of all responses to the question "How likely would you be to recommend this provider to your family and friends (on a scale of 0 to 10)" on our nationally-recognized NRC patient surveys.

Patient Comments

  • Nov 28, 2019

    Excellent, knowledgeable, and genuinely interested in what I had to say.

  • Nov 18, 2019

    He reviewed the test results with me in language that I could understand. We made plans for future visits based on my diagnosis.

  • Nov 14, 2019

    My appointment time was honored and I was not kept waiting. I do wish Dr. Penisi had researched my condition more closely and would have been able to have a deeper conversation about it.

  • Nov 12, 2019

    Well organised and extremely professional team

  • Oct 24, 2019

    Dr.Pennesi went above and beyond to make sure i got the best possible care i could receive. Being a patient for more than a decade at casey eye institute i have never had anyone treat me and my family as well as he has.

  • Sep 27, 2019

    He was great and was able to answer my questions.

  • Sep 19, 2019

    Extremely professional and well organised team. Looked after me very well and I genuinly appreciate their help.

  • Aug 22, 2019

    He doubly cared and examed photos carefully.

  • Aug 01, 2019

    He is the best! Always full of information and looking out for the patient!

  • Jul 26, 2019

    You guys are great. Dr Penisi was great. Spent time. Knowable. Supportive. Very pleased

  • Jul 25, 2019

    Always an awesome experience!

  • Jul 05, 2019

    The visit was good

  • Jun 07, 2019

    Dr. Pennesi has always been extremely knowledgeable and responsive to my son's health care needs. I consider him a critical part of [Name] healthcare team.

  • Jun 01, 2019

    Dr P. Is great. Just one of his helpers looks like always in the bad mood. I would recommend him to smile little bit by that patients and family.

  • May 24, 2019

    Thorough and very professional.

  • May 23, 2019

    Dr. Pennesi was warm, funny, personable, and very professional.

  • May 23, 2019

    Overall the best under all aspects.

  • May 17, 2019

    Was able to answer my questions about my particular eye condition and about how it is passed on, as well as who can pass it to off-spring.

  • May 16, 2019

    dR. pennisi, Hardew Mahto and all the support people I deal with are caring, highly competent and dedicated to serving their patients completely.

  • May 11, 2019

    The only thing that I would say is that I would like to know as soon as possible whether or not Dr. Pennesi has placed me with the... my retina tracker and so I can get the very latest on what is... what is going on for my particular gene mutation.

  • Apr 18, 2019

    Very helpful

  • Apr 12, 2019

    Doc Penesi is a great provider and human being. He is such professional and he shares his knowledge with his patients. He would not gives you illusions on care plans and at the same time he would try his best. His team as well, his assistant, the genetic counselor, and all his vision technicians are amazing. We are having the best experience ever , after years being seeing doctors and specialists, in U.S and Europe. We could not be happier and feeling more than blessed for being under their cares, especially when your loved ones have a such high grade diagnosis that sounds scary. Thank you all , for being a such excellent team and taking care of my precious daughter.Sincerely, [Name]

  • Mar 18, 2019

    Very friendly and knowledgeable

  • Mar 17, 2019

    All staff at Casey eye are always caring, kind and Dr’s explain as best they can about tests and future eye issues 

  • Feb 22, 2019

    Dr. Pennesi was awesome! He didn’t seem in a rush and was happy to answer any and all questions we had.

  • Feb 18, 2019

    I appreciate the level of care and considered thinking provided by Dr. Pennesi and also by Dr. Huber. Dr. Pennesi thinks about my situation and evaluates my current vision from the day's test results and decides how much has deteriorated since the last visit. Dr. Pennesi has an easy, upfront way of relating to patients. He discusses some things from a research or scientific view which is nice. He went over preventative measures to preserve my remaining vision, which is a good reminder. We are interested in participating in a clinical trial for my RP. Dr. Pennesi discussed the likelihood of that for my situation, and the different gene therapy methods developing. Dr. Huber asked me good questions before Dr. Pennesi's arrival and discussed gene therapy for the future. I hope I will see Dr. Huber next time as well when I am a patient at Casey Eye Institute.

  • Jan 29, 2019

    I have been seeing Dr. Pennisi now for a few years as well as my older brother. He's an amazing doctor and I am very thankful for him.

  • Jan 20, 2019

    Dr. Pennesi was very very thorough and very very clear in his explanations and everything was on time, which was absolutely wonderful so I couldn't speak more highly of them. Thank you.

  • Jan 06, 2019

    Dr. Pennesi is excellent doctor. We would like to thank him for his care and the we're thanking also his helper Annalise, she's very helpful, so I thank you for them.

  • Jan 05, 2019

    Was very helpful and looked into things further than what I expected to have happen, and we were very pleased, because he was able to find out things that possibly can be helped with my eyes. So, thank you very much. Bye.

  • Dec 24, 2018

    He is obviously extremely knowledgeable but also quite approachable and human in his interactions. He listens to my thoughts and ideas as well as just giving me his opinions.

  • Dec 13, 2018

    Yes, Dr. Pennesi is an extremely good specialist who I get on very very well with very laid back very easy and gives you the state of the nation as far as (INAUDIBLE).

  • Dec 04, 2018

    He was professional, on time and informative

  • Nov 21, 2018


  • Nov 10, 2018

    Everything is working: good organization, good doctors, very nice people, excellent assistance.

  • Nov 05, 2018

    Living with blindness is scary for a teenager. Dr Pennesi has given me hope that if my vision was to get worse there are options to hopefully stop it or make it better.

  • Nov 03, 2018

    Our son was diagnosed with RP, Dr. pennesi has been kind enough to sit with us and answer all our questions and concerns.

  • Nov 03, 2018

    He was very through. Explained everything in detail. Easy to talk to.

  • Sep 27, 2018

    He was absolutely the best eye physian I?ve ever had. He listens to what you are saying and answers to the best of his knowledge and if he?s not sure he will let you know.

  • Sep 27, 2018

    All the questions I had were answered. He gave me encouragement and Ifelt positive about my condition when I left.

  • Sep 19, 2018

    Dr. Pennesi is always pleasant, informative and well qualified for his position.

  • Sep 15, 2018

    This was my first visit with Dr Pannessi. I thought he was very clear and helpful. He listened and was very personable..

  • Aug 30, 2018

    The staff are kind, but logistics are a nightmare. Every time I visit (Casey Eye Institute, specifically), we wait an exorbitant amount of time to be met. Yesterday, my son and I waited nearly an hour and a half in the room before the doc came to see us. In fact, I started walking out and found several staff, including the doc, standing in the hallway talking. I have a job, too, and if I asked any of the doctors to come to a meeting at my office, then made them wait nearly an hour and a half for the meeting to start, they wouldn't stand for it. It's unacceptable in every other part of society, yet happens regularly at Casey.

  • Aug 18, 2018

    Exceptional knowledge of my disease. Always takes time to answer questions and to keep me updated on current research and possible treatments.

  • Aug 17, 2018

    He was compassionate and helpful. He understood my concerns, and had good alternative treatment for the disparity of acuity between my eyes. He gave me a prescription for sunglasses. He was encouraging about the possibility of clinical trials for my RP mutation to one day include females.

  • Aug 03, 2018

    We got the answers to our questions

  • Jul 27, 2018

    The doctor did not tell me if my vision got worse and never told me the numbers of each eye. Basically he did not tell me what I wanted to hear.

Make an Appointment

(503) 494-8386

Refer a Patient

Physician Advice and Referral Service

I see patients at