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Dr. Timothy Sullivan is a board certified ophthalmologist and glaucoma specialist serving patients in New Hampshire. He brings comprehensive expertise in both the medical and surgical management of eye conditions, with a particular focus on glaucoma care. Dr. Sullivan graduated magna cum laude from Dartmouth College and earned his medical degree from the University of Michigan Medical School. He completed his ophthalmology residency at New York Eye and Ear Infirmary and pursued advanced training through a glaucoma fellowship at Wills Eye Hospital in Philadelphia. Beyond his clinical practice, Dr. Sullivan is actively involved in clinical research, with his articles and findings published in various journals and presented at multiple ophthalmology meetings. He is dedicated to community service and volunteerism within his local communities and maintains memberships in several professional organizations.

Dr. Laura A. Gadzala is an ophthalmologist who focuses on conditions of the eyelids, orbit, and tear drainage system. She enjoys helping patients get back to daily life, and she prioritizes clear explanations so patients and families understand the diagnosis and the options for care. She also values collaboration, encouraging questions and working with patients' support networks when planning treatment. Her clinical interests include eyelid, orbit and tear duct surgery; evaluation and management of orbital tumors and eyelid skin cancer; thyroid eye disease; and specialized procedures such as corneal neurotization. She also uses Botox for appropriate conditions, including blepharospasm and hemifacial spasm. Dr. Gadzala completed medical school at the University of Michigan, ophthalmology residency at Oregon Health Sciences University, and an oculoplastic surgery fellowship at West Virginia University Hospital.

Dr. Purak Parikh is a board-certified ophthalmologist who specializes in cornea, external disease, and refractive surgery. He completed his medical school at Dartmouth/Geisel School of Medicine, where he was recognized with the Arnold P. Gold Humanism in Medicine award. He then completed his ophthalmology residency at the University of Pennsylvania/Scheie Eye Institute, earning the Resident Teaching Award. Dr. Parikh further advanced his expertise through a fellowship in cornea, anterior segment, and refractive surgery at the University of Michigan/Kellogg Eye Institute. In addition to his clinical practice, Dr. Parikh has served as President of the New Hampshire Society of Eye Physicians and Surgeons. He is actively involved in research and education, having authored book chapters and research manuscripts on corneal transplantation and cataract surgery. He frequently lectures and moderates sessions at national conferences on topics such as LASIK, PRK, cataract surgery, and keratoconus. Originally from New Jersey, Dr. Parikh was drawn to New Hampshire by the great outdoors. In his spare time, he enjoys woodworking, tennis, skiing, and hiking in the White Mountains with his wife, Caitlin, and their two children. He is proud to call New Hampshire home and looks forward to providing exceptional eye care to his patients.

Dr. Claudia Bartolini is an ophthalmologist who provides medical and surgical care for glaucoma, cataracts, and external eye disease. Raised in Hampton, New Hampshire, she is excited to serve patients on the Seacoast. She earned her undergraduate degree in chemistry at Dartmouth College and received her medical degree from Tufts University School of Medicine. She completed ophthalmology residency at Tufts New England Eye Center and advanced glaucoma fellowship training with Tufts New England Eye Center and Ophthalmic Consultants of Boston. Dr. Bartolini specializes in the diagnosis and long-term management of glaucoma, including minimally invasive glaucoma surgery (MIGS) and other surgical options when needed. She also performs small-incision cataract surgery, including complex cases, and treats disorders affecting the front surface of the eye. She is board certified in ophthalmology and is active in professional societies. Outside the office, she enjoys time with her family and outdoor activities in New Hampshire.

Dr. Heather Bartels is a board-certified comprehensive ophthalmologist and cataract surgeon who joined The Medical Eye Center in April 2023. She offers advanced intraocular lens implants, including options for astigmatism and presbyopia, to reduce patients' dependence on eyeglasses. She also provides laser treatments and minimally invasive glaucoma surgery (MIGS) for glaucoma management. Originally from Arkansas, Dr. Bartels completed her undergraduate degree at the University of Arkansas and earned her medical degree at the University of Arkansas for Medical Sciences, where she was elected to the Alpha Omega Alpha Honor Society. She then completed a transitional year internship in Virginia and an ophthalmology residency at Texas Tech, during which she received the Outstanding Grand Rounds Award and served as chief resident. She began her career in private practice in Arkansas before relocating to New Hampshire. Dr. Bartels is a member of several professional organizations, including the American Academy of Ophthalmology, the American Board of Ophthalmology, the American Society of Cataract and Refractive Surgery, and Women in Ophthalmology. She is dedicated to building strong doctor-patient relationships to enhance the quality of ophthalmic care through prevention, diagnosis, and treatment. In her free time, she enjoys family activities, travel, and home organization projects, and she looks forward to exploring New England.

Dr. Maxwell Harley is a comprehensive ophthalmologist at Dartmouth Health in the Monadnock Region. He enjoys helping patients regain clarity after cataract surgery and prides himself on building meaningful connections through attentive listening and clear guidance. Dr. Harley earned his MD at the Lewis Katz School of Medicine at Temple University, completed a transitional year at Geisinger Medical Center, and finished ophthalmology residency at New York Medical College. His approach blends meticulous surgical technique with straightforward education so patients understand their diagnosis, risks, and choices. From managing dry eye and diabetes-related eye disease to offering cataract surgery and minimally invasive glaucoma surgery, he focuses on practical solutions that improve daily life and vision.

Dr. Sabrina K. Khalil was drawn to ophthalmology because she loves helping to protect or restore vision. Her goal is to improve the quality of life and functional independence of her patients. By understanding their needs and goals, she can better individualize care. As someone who is very detail-oriented, she also loves the unique intricacies of the eye. In some ways, the eyes really are "windows to the soul" because they often reveal conditions in the body that otherwise may not have manifested. She finds the field of ophthalmology exciting because of the growing technological advancements that allow her to provide care and treatments in ways never before possible. She considers it an absolute privilege to care for patients and treats them just as she would her own family or friends. She looks forward to building deep, meaningful, and long-lasting connections with her patients in the Dartmouth Health and Mt. Ascutney Hospital and Health Center community.

Dr. Mohamed Guenena is a board-certified ophthalmologist who provides comprehensive eye care with special expertise in cornea, cataract, and refractive surgery. He earned his medical education at Cairo University and completed additional training in the United States, including a research cataract and refractive fellowship at the Storm Eye Institute at the Medical University of South Carolina and a two-year cornea fellowship at the University of Texas Southwestern. Dr. Guenena performs corneal transplant surgery and treats medical corneal conditions, including severe dry eye. He also offers advanced cataract surgery with premium lens options and laser vision correction, including LASIK. As a comprehensive ophthalmologist, he manages a broad range of eye conditions such as glaucoma, diabetic eye disease, and retinal disorders. He has authored and presented work at national and international ophthalmology meetings and remains active in clinical research. Dr. Guenena speaks English, Arabic, and Spanish.

Dr. Sivashakthi Maeder is a board-certified ophthalmologist and neuro-ophthalmology specialist who provides comprehensive care for patients with vision and eye-movement disorders linked to the brain, optic nerves, and eye muscles. As the Director of Neuro-Ophthalmology at Dartmouth Hitchcock Medical Center, she evaluates and manages complex conditions such as optic nerve disorders, pseudotumor cerebri, and ocular myasthenia gravis, helping patients cope with symptoms like double vision. Her clinical expertise extends to thyroid eye disease, orbital tumors, and she offers advanced surgical options including micro-incisional cataract surgery and adult strabismus surgery when needed. Dr. Maeder also utilizes Botox for therapeutic purposes in selected cases. She is dedicated to improving patient outcomes through precise diagnosis and tailored treatment plans. In addition to her clinical practice, Dr. Maeder serves as an Assistant Professor of Surgery at the Geisel School of Medicine at Dartmouth, where she contributes to medical education. She is also the President of the New Hampshire Society of Eye Physicians and Surgeons, reflecting her leadership in the field. Dr. Maeder joined Dartmouth Health in 2015 and is committed to providing high-quality, patient-centered care.

Dr. Schertzer is a glaucoma sub-specialized and general ophthalmologist with over 25 years of clinical experience, providing care as a consultant and later taking over a permanent practice in Vancouver. He has served on faculty at the Geisel School of Medicine at Dartmouth College and Dartmouth-Hitchcock Medical Center, and previously directed the West Coast Glaucoma Centre while holding an Associate Clinical Professor appointment at the University of British Columbia's Department of Ophthalmology & Visual Sciences. Much of his non-clinical time is dedicated to using technology for patient education, including hosting the Talking About Glaucoma podcast, maintaining a YouTube channel, an Instagram channel, and co-founding the Glaucoma Patient Group Facebook page. He also contributes to professional education through speaking engagements on clinical glaucoma care, surgical techniques, ethical issues, and electronic health record implementation.

Dr. William G. Gensheimer is a board-certified ophthalmologist who joined Dartmouth Health in 2021. He holds a faculty position as an Associate Professor of Surgery at the Geisel School of Medicine at Dartmouth, where he is involved in teaching and surgical education. Dr. Gensheimer completed his medical degree at the University of Rochester in 2010. He then undertook an internal medicine internship at the University of Rochester Medical Center in 2011, followed by a residency in ophthalmology at the Flaum Eye Institute in 2014. His specialized training includes a fellowship in ophthalmology at the University of Colorado Health Sue Anschutz-Rodgers Eye Center in 2015. He provides comprehensive eye care services at Dartmouth Hitchcock Medical Center in Lebanon, New Hampshire, and Mt. Ascutney Hospital and Health Center in Windsor, Vermont. Dr. Gensheimer is dedicated to offering high-quality ophthalmological care to his patients.