Doctors & Staff
Meet the experienced and friendly doctors and staff who make Walnut Hill Pasadena Optometrics a proud provider of vision care products and services in Pasadena.
Wendy Shem Yeh, O.D.
Dr. Wendy Shem Yeh received her B.A. in Physical Sciences from the University of California at Berkeley in 1991. In 1996, she received her Doctor of Optometry degree from the University of Houston College of Optometry, having completed clinical rotations in Barbers Point, Hawaii, and Boise, Idaho.
Dr. Shem has been practicing optometry for over 25 years, providing eye and vision care emphasizing family practice, contact lenses, medical eye care, and surgical co-management.
Dr. Shem truly cares for her patients of all ages but is especially passionate about treating and preventing vision problems in her pediatric patients with vision therapy and myopia control treatments. She absolutely loves to see her younger patients gain confidence as they improve their visual skills or excel in sports after being treated with orthokeratology!
Dr. Shem began her career practicing in the San Francisco Bay Area, then joined a long-standing ophthalmology practice in Honolulu, HI. In 2000, she moved to Southern California to manage a private optometric practice and provided optometric care throughout the San Gabriel Valley. Dr. Shem is a Clinical Faculty Member of Western University College of Optometry teaching and providing clinical experience to future optometrists. She is a trustee board member of the San Gabriel Valley Optometric Association and has served multiple terms as President and Director of Continuing Education. She is a member of the California Optometric Association and the American Optometric Association. She is also a member of Vision Source, the premier network of independent private practice optometrists. Dr. Shem has volunteered with the Lions Club International and the Southern California Special Olympics to provide vision screenings and eye care to the underserved and special populations.
Dr. Shem has been a resident of the Pasadena area for over 15 years. She currently resides in Monrovia with her family. As her children are becoming responsible young teens, you may see them in the office working and assisting with patients now! Dr. Shem is an ardent supporter of the Pasadena Educational Foundation, South Pasadena Educational Foundation and previously served on the founding committee or as chairperson of the Field Elementary School Annual Gala four consecutive years since its inception. She and her family are active members of the American Youth Soccer Organization and South Pasadena Unified School Boosters. When not cheering on her children on the soccer or track fields, she can be found skiing, traveling, and taking her children to the beach.
Kristen Phifer, O.D.
Originally from Pasadena, CA, Dr. Phifer received her Bachelor of Science degree in Biology from Loyola Marymount University and her Doctor of Optometry degree from Western University of Health Sciences, graduating as a member of the Beta Sigma Kappa Honor Society.
Dr. Kristen Phifer is an optometrist with therapeutic and glaucoma licensure. She started her eye care career years ago as a vision therapist in the practice working alongside Dr. John Tassinari before proceeding on to Optometry School. She offers an extensive scope of practice including general eye healthcare, fitting contact lenses, diagnosing, managing and treating various eye conditions and diseases; with a special interest in vision therapy and pediatrics. Dr. Phifer has experience in working with children and adults with learning-related vision problems, tracking and focusing issues, binocular dysfunctions, and visual perceptual deficits.
Dr. Phifer’s passion for good health and wellness show in the way she carefully listens to her patients in effort to meet their needs. Her upbeat personality and calm demeanor are welcomed by her patients.
During her free time, Dr. Phifer enjoys volunteering in underserved communities and is an active tutor and mentor for youth. On her days off, she looks forward to spending time with family, friends, her dog Darla, and traveling.
Jonathan Kiriboon, O.D.
Born and raised in Southern California, Dr. Jonathan Kiriboon started his optometric journey with our clinic as an optometric technician. He soon decided to pursue his doctorate and he was accepted into Western University of Health Sciences College of Optometry, where he graduated with honors and is a member of the Beta Sigma Kappa honors society. After graduation, Dr. Kiriboon completed a residency in Pediatric Optometry and Vision Rehabilitation Therapy in Washington.
Dr. Kiriboon has had extensive training in managing and treating various binocular vision dysfunctions, myopia (nearsightedness) control and ocular diseases. Having “good vision” is more than just the coveted 20/20 line, it’s also how well your eyes coordinate together, how well you can track a line of text without losing your place, and how well you can understand and make sense of what you see. These are all issues glasses alone cannot fix. Dr. Kiriboon is a firm believer in early detection and intervention for young patients that may have underlying visual needs.
By setting patients up for success early on, Dr. Kiriboon believes this will improve their quality of life down the road. Dr. Kiriboon is passionate about helping patients from all walks of life to reach their maximum potential.
John Tassinari, O.D., F.A.A.O. (emeritus)
Dr. John D. Tassinari is a Cal State University Northridge Alumnus and a 1987 graduate of Southern California College of Optometry. He completed a residency in Children’s Vision at State University of New York. Dr. Tassinari specializes in Vision Therapy and vision as it relates to learning and development.
Dr. Tassinari has been in private practice for over 25 years. Currently, Dr. Tassinari teaches full time and serves as Associate Professor and Chief of Pediatric Optometry at Western University of Health Sciences College of Optometry.
Dr. Tassinari is currently pursuing academia full time and is no longer actively seeing patients in the clinic, but he continues to be an active supporter of the practice.
Sierra
Sierra is typically the first person you will see at our clinic and primarily assists our administrative front desk department. She comes from the dermatology field and has changed gears to optometry and has been loving it. She is the first point of contact for all your visual needs and is available to answer all questions you may have relating to the practice, appointments, insurance, or scheduling any of your friends and family members!
In her free time she enjoys looking for fun new hair colors and styles.
Reyna
Reyna specializes in assisting our vision therapy department. She enjoys working with patients of all ages to improve their ocular skills to ensure each person’s reaches their maximum potential. She is here for all your vision therapy needs and questions. When she is not helping the vision therapy department, she is helping other departments at our office and is available to help anywhere.
In her free time she enjoys long walks and coffee breaks.
Maureen
Maureen is one of our opticians available to help with all your glasses needs. She has been working in the eyecare industry for more than 6 years and is very knowledgeable in lens designs and options. She has a keen eye for picking the right frame based on the patient’s style, desire, and personal preferences.
In her free time she enjoys playing soccer, spending time with family, and going to various sports events.
Savannah
Savannah is one of our ophthalmic technicians who assisted the doctors and helped pre-test our patients. She also helps the optical department and is available to help with all of your glasses needs. She has been working in the eye care industry for over 4 years and loves helping patients selecting the perfect frame and lens style for her patients.
In her free time she enjoys binge watching her favorite shows and spending time with friends and family.