About
Our Eye Clinic in Waterloo

Following undergraduate study at the University of Regina, Dr. MacDonald graduated from the University of Waterloo School of Optometry in 1992, receiving the General Proficiency Medallion and the Attridge Award for Excellence in Pathology. Since that time, he has been engaged in full-scope private practice in Waterloo, with a special interest in ocular and systemic disease.

Following graduation, Dr. MacDonald stayed involved with the School of Optometry, acting as a clinical supervisor in the Ocular Health Clinic, and was selected Clinician of the Year. Dr. MacDonald was elected to the Ontario Association of Optometrists Board of Directors in 1999 and served a two-year term as OAO President, ending in 2007. He then assumed a staff position as a Policy Consultant, working on scope-of-practice expansion and intra- and interprofessional collaboration.

In early 2010, Dr. MacDonald was elected to the Council of the College of Optometrists of Ontario. He was re-elected in 2012 and retired from Council in early 2016. Dr. MacDonald is a founding member of the Eye Health Council of Ontario (EHCO), a multidisciplinary group focused on improving the delivery of eye care to Ontarians. He has worked with the Waterloo-Wellington Local Health Integration Network, Health Human Resources, and Vision Strategy Task Forces, the Health Quality Ontario Glaucoma Clinical Advisory Expert Panel, and the University of Waterloo Clinical Research Ethics Board.

In 2012, Dr. MacDonald became a Fellow of the American Academy of Optometry and is the immediate Past-Chair of their International Admittance Committee. In early 2013, he was accepted as a member of the Optometric Glaucoma Society, and in late 2015, was granted membership in the Optometric Retina Society. His research, writing, and lecturing focus on glaucoma, ophthalmic imaging, and retinal vascular disease: a number of his publications can be found here.

In 2017, Dr. MacDonald was recognized as a Distinguished Alumni of Honour as part of the School of Optometry’s 50th Anniversary Celebrations, one of only eight recipients from a total of some 3000 graduates of the program. In 2018, he received the Cobean Award, the Ontario Association of Optometrists’ highest honour, recognizing contributions to advocacy, regulatory, and educational initiatives.

In late 2024, Derek became the first optometrist in Canada, and only the ninth in the world, to be awarded the status of Diplomate (Glaucoma) in the American Academy of Optometry.

In his few non-eyeball-related hours, Derek enjoys cycling, photography, and chasing that little white ball, usually through the trees, as Karen patiently waits in the middle of the fairway.

Born in Kitchener, Dr. MacDonald graduated from the University of Waterloo in 1992 with a Bachelor of Science and Doctor of Optometry degree. She was the recipient of the TT Beattie Binocular Vision Award. Upon graduating, Dr. MacDonald served as a research optometrist at the Centre for Contact Lens Research. Her work with the initial clinical trials of silicone hydrogel soft contact lenses (now the industry standard) became one of the first published papers on the subject: several of her publications can be viewed here. Shortly thereafter, Dr. MacDonald became a Fellow of the American Academy of Optometry.

More recently, her interest in pediatric eyecare has led her to observerships at the Pediatric Eyecare Clinic of the Carolinas in 2003 and the Hospital for Sick Children in 2004. She is also qualified to perform visual perceptual testing in children. 2010 saw Dr. MacDonald voted Gold Medalist for Optometrists in the Reader’s Choice Awards, sponsored by the KW Record.

In 2011, Dr. MacDonald assumed the role of Chair of the Ontario Association of Optometrists’ Children’s Vision Working Group, championing the Eye See Eye Learn program with the goal of ensuring that all children undergo a comprehensive eye examination before entering kindergarten. To this day, her passion remains in pediatric eye care.

Out of the office, Karen enjoys volunteer work (often focused on providing meals to those in need) and posting a golf score far lower than Derek could ever dream of.

Dr. DiRenzo is a graduate of the University of Waterloo School of Optometry (2006), where she also obtained a Bachelor of Science degree. She completed an ocular disease and therapeutics externship at Barnet Dulaney Perkins Eye Center in Mesa, Arizona, followed by a primary care externship at Brisson Leis & Associates in Guelph, Ontario.

She has also attended a specialty contact lens training seminar at the Vision Care Institute of Johnson & Johnson in Jacksonville, Florida. Dr. DiRenzo is a member of both the Canadian Association of Optometrists and the Ontario Association of Optometrists.

Outside the office, Deanna enjoys curling up with a good book, downhill skiing, and playing soccer. She’s also an avid traveller and has participated in an eye care mission in Nicaragua, providing free eye examinations and glasses to the underprivileged.

Dr. Julian Prosia is an optometrist and leading innovator in amniotic membrane therapy in Canada. With a focus in Dry Eye and ocular surface disease management, he introduced Canada’s first doctor-owned amniotic membrane company, Ophthalogix Canada, expanding national access to advanced regenerative ocular treatments.

After graduating in 2021, Dr. Prosia began his Dry Eye journey in Boca Raton, Florida where he worked alongside ophthalmology in a high-volume surgical and ocular surface disease setting. During this time, he also served as an official eye doctor for the Ultimate Fighting Championship (UFC), performing vision assessments and clearing professional fighters for competition. In 2023, he was honoured as a Top Doctor in Boca Raton, recognizing his clinical excellence and impact in the field.

Over his career, Dr. Prosia has performed more than 2,000 amniotic membrane procedures and managed over 50,000 Dry Eye cases. He is recognized as a Key Opinion Leader and currently serves as Medical Director for four leading Dry Eye companies, contributing to clinical innovation, research integration, and physician education across Canada.

Dr. Prosia has a special clinical focus on autoimmune-based Dry Eye disease. He co-manages complex ocular surface cases alongside the McMaster University / St. Joseph’s Healthcare Hamilton Rheumatology team, helping facilitate early diagnosis and coordinated management of systemic autoimmune conditions that affect the eye. His collaborative approach ensures patients receive comprehensive, multidisciplinary care.

Deeply passionate about improving patients’ quality of life, Dr. Prosia believes that managing Dry Eye is more than treating symptoms, it is restoring comfort, function, and confidence. He founded the Canadian Dry Eye Support Group to provide education, guidance, and community to patients searching for answers and support. His mission is simple: help people feel better, see better, and live better. For Dr. Prosia, Dry Eye care is the perfect avenue to combine advanced medical therapy with meaningful human impact, putting smiles back on patients’ faces every day. Outside of practice, Dr. Prosia enjoys golf, hockey, working out, and spending quality time with his wife Renata and his daughter Esmeralda.

Avery has been a part of the Ilex team since 2015. She holds a diploma in Medical Office Administration and manages the optical side of Ilex. You’ll often hear her voice on the phone, and you will find her helping in the dispensary, especially if you’re having a hard time making a decision on which frame to pick. Outside of the office, you will find Avery singing and performing on a stage, writing music on one of her many instruments, or on an outing with her husband and 2 daughters.

Ashley joined Ilex Eye Associates in early 2019. After ten years as a hairstylist, she decided it was time for a change and headed back to Conestoga College. You’ll find her smiling face at our reception desk, and performing special testing, including photography, imaging, and visual field testing. Ashley spends her free time with her husband and 2 daughters, watching movies, playing games, camping, and hiking.

Ayantu previously interned with Ilex in 2022 and, following the completion of her education and some time in the work world, returned in early spring 2024 as one of the newest additions to the team. Outside of work, she enjoys spending time with her family, watching shows, and picking up new hobbies.

Debbie joined Ilex Eye Associates in the summer of 2025, following her completion of the Health Office Administration program at Conestoga College. She is the newest addition to the team, and you’ll likely see her smiling face greeting you at reception or hear her voice answering your calls. Outside of the office, she spends time taking road trips with her husband, reading books, and painting.

Harman completed her Health Office Administration Diploma in mid-2024 and joined the Ilex team shortly thereafter. Originally from the Punjab state of India, she came to Canada as an international student and has enjoyed experiencing Canadian culture and activities. Her hobbies include exploring new things, reading fiction, dancing, and listening to music.

Melissa joined the Ilex team in late summer 2021. She is quickly learning the ropes in administration, dispensing, and special testing. During her free time, she enjoys taking walks with her two daughters, dancing like no one is watching, and singing to her heart’s content. You will often find her taking photos of anything related to nature, especially animals.

Raman joined Ilex in March 2024 during her internship, bringing with her a wealth of skills and knowledge. Holding a Diploma in Health Office Administration from Conestoga College, Raman is fluent in English, Punjabi, and Hindi. Outside of work, she indulges her creative side with a passion for painting, dancing, and singing.

Shannon came aboard in spring 2021 after fifteen years in customer service. She has hit the ground running, and you’ll likely meet her during your visit at reception, during special testing, or as you pick out your new glasses, or all three. When she’s not at Ilex, Shannon enjoys spending time outdoors and with her family, where she is outnumbered by boys (including the dog).