A History of Caring for Eyes

Welcome to the Shammas Eye Medical center. We have three locations in Southern California, including Lynwood, Downey and Whittier. Dr. H. John Shammas has been in practice in Lynwood since 1977. The practice has been known for pioneering modern cataract surgery, being amongst the first in the area to offer phacoemulsification for removal of the cataract; amongst the first to utilize ultrasound measurements of the eye to calculate the power of the intaocular lens (the implant); and amongst the first to insert these implants into patients’ eyes so they do not have to wear thick lenses in their glasses, often called “coke bottle glasses”.

We, at the Shammas Eye Medical Center, continue that tradition of staying at the forefront of technology. We are equipped with the latest diagnostic instruments, lasers and surgical equipment and devices under the leadership of Dr. H. John Shammas, Dr. Maya Shammas and Dr. Renu Jivrajka. In addition to performing complete eye examinations, we have have full optometric services (prescribing and dispensing glasses) at each of our locations. Our distinguished physicians have been widely recognized for their outstanding skills and expertise in diagnosis and treatment of ocular diseases. They are certified by the American Board of Ophthalmology and are dedicated to serving their respective communities.

Contact us today for more information or to make an appointment. We look forward to seeing you!

H. John Shammas, M.D., is an American Board Certified Ophthalmologist who completed his training at the University of Iowa. He values teaching and maintains his title as Clinical Professor at the University of Southern California (USC). He has earned many awards from the American Academy of Ophthalmology and the American Medical Association.  Dr. Shammas has published approximately 150 original articles in the American and international literature, multiple chapters for medical books, and has written multiple books focused on ultrasound diagnosis of medical eye conditions, instructional books for cataract surgery, and Intraocular Lens Power Calculations. 

Dr. H. John Shammas has led the Shammas Eye Medical Center since the 1980’s, maintaining its high level of excellence. He has extensive experience in laser procedures to correct medical conditions of the eye, especially in diabetic patients and after cataract surgery. He continues to be an active member of the American Academy of Ophthalmology, American Society of Cataract and Refractive Surgeons, and routinely gives courses and lectures around the world. His “Shammas Formula” is routinely used by cataract surgeons worldwide in post-refractive cataract patients. His expertise and experience are integral to how he cares for his patients.

Thao Vu, M.D. is a comprehensive eye surgeon who specializes in the medical and surgical treatment of eye diseases. She graduated from Brown University with a Bachelor of Science in Neuroscience.  She then completed her medical education and ophthalmology residency at the University of California, Irvine.

Dr. Vu specializes in cataract surgery and is experienced in premium intraocular lens implantation as well as minimally invasive glaucoma surgery (MIGS). She is proficient in intravitreal injections and lasers for the treatment of retinal diseases such as diabetic retinopathy and macular degeneration. She is a member of the American Academy of Ophthalmology. As a healthcare professional, Dr. Vu strives to provide compassionate care and enjoys educating patients about their conditions and treatment options.

Maya Shammas, M.D., is an American Board Certified comprehensive eye surgeon who specializes in the medical and surgical treatment of eye diseases. She completed her undergraduate degree Cum Laude with Honors from UCLA.  She then received her Medical Degree from Weill Medical College at Cornell University in New York City. She continued her training in Ophthalmology at Cornell University at New York Presbyterian Hospital of Cornell University. 

Dr. Maya Shammas has a special interest in the medical treatment of the retina for conditions such as macular degeneration and diabetic eye diseases. Her experience in glaucoma treatment includes “Minimally Invasive Glaucoma Surgery” (MIGS). She has expertise in complex cataract surgery with the goal of achieving the best possible vision after surgery. She has co-authored multiple articles on axial length measurement and intraocular lens power calculations; these studies aim to improve vision post-cataract surgery. She is a member of the American Academy of Ophthalmology and the American Society of Cataract and Refractive Surgeons, and has been voted onto the “Southern California Super Doctors” list multiple times. She believes that each patient is unique and treatment should be tailored to the individual.  

Melissa Mayberry Crowley, M.D., is a board-certified ophthalmologist with over 24 years of experience and more than 20,000 successful cataract surgeries performed. She specializes in complex cataract surgery, premium lens implantation, and advanced glaucoma care, while also treating a wide range of retinal and ocular surface conditions.

After earning her undergraduate and medical degrees from the University of Iowa, Dr. Mayberry completed her ophthalmology residency at the USC Doheny Eye Institute, followed by a cataract surgery fellowship with Dr. William De La Peña. She is known throughout Southern California for her surgical expertise, compassionate care, and commitment to exceptional patient outcomes.

Renu Jivrajka, M.D., is an American Board Certified ophthalmologist and glaucoma specialist who specializes in the medical and surgical treatment of eye diseases. As a glaucoma specialist, she is highly skilled in the surgical treatment of glaucoma and combines minimally invasive glaucoma surgery with cataract surgery to help prevent progression of the disease. She is a highly skilled cataract surgeon using the latest innovations in premium intraocular lenses. She is highly proficient in managing medical retinal conditions, including diabetic retinopathy and macular degeneration, with the use of intravitreal medications and laser techniques.

She graduated Cum Laude from the University of California, Berkeley, and went on to receive her medical degree at the University of Southern California (USC). She completed her training in Ophthalmology in Chicago at the Eye and Ear Infirmary and pursued advanced training with a fellowship in glaucoma at Jules Stein Eye Institute at UCLA. Dr. Jivrajka has published research articles on cataract surgery and is an active member of the American Academy of Ophthalmology. Dr. Renu loves developing long-lasting relationships with her patients and helping them keep the best vision possible when faced with chronic vision-threatening illnesses.

Ramie Sahota Shah, O.D. is a comprehensive optometrist who focuses on preventing and managing ocular diseases. She graduated with her Bachelor of Science in Biological Sciences from the University of California, Riverside. She then received her Optometry degree from the University of Missouri, St. Louis. Shortly thereafter, Dr. Sahota Shah completed her ocular disease residency at the University of California, Berkeley School of Optometry.

She is certified to diagnose and treat ocular diseases, including diabetic retinopathy and glaucoma. She uses her professional experience to maximize each patient’s visual potential. She takes pride in providing the best eye care to every patient she encounters. Outside her clinic, she enjoys spending time with loved ones, testing out new recipes, and staying active by attending various workout classes.