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Born in the small rural ski resort town of Show Low, Arizona, Cristal Sumerlin is a dedicated Physician Assistant specializing in Internal Medicine. With a strong passion for patient care and a desire to play an active role in their treatment and well-being, she chose the professional career path of a Physician Assistant after working as an X-Ray Technician. Cristal fell in love with medicine and recognized the need to further her education to better serve her patients and the community.

Cristal takes great pride in both her personal and professional accomplishments. As a mother and military spouse, she has successfully balanced the demands of family life while pursuing her professional goals. Her commitment to her patients and dedication to her work make her a source of pride and inspiration.

In the field of Internal Medicine, Cristal's strengths lie in managing complex disease processes such as diabetes. Her previous experience as an orthopedic technician and x-ray tech in an orthopedic practice has also honed her skills in orthopedics. She finds fulfillment in working with patients facing orthopedic conditions and providing comprehensive care.

Beyond her career, Cristal enjoys spending time outdoors and engaging in activities such as camping, hiking, and traveling. She cherishes these moments with her friends and family, as they provide a source of rejuvenation and happiness outside of her job.

With her unwavering dedication, clinical expertise, and compassionate approach, Cristal Sumerlin is an invaluable asset to Dr. Richard Lam's office. She strives to make a positive impact on her patients' lives and is committed to providing comprehensive and personalized care to improve their overall well-being.

Gene L. Syn, MD, is one of the skilled physicians practicing at Minimally Invasive Medical Group, which has offices in Lake Forest, Mission Viejo, and Irvine, California. 

He is a second-generation Korean-American who was born in Los Angeles and raised in Orange County, California.  He graduated from the UCLA School of Medicine in 1992.  He then did his general surgery residency at the New York Flushing Hospital Medical Center from 1992 to 1997. He further specialized in colon and rectal surgery at the Greater Baltimore Medical Center from 1997 to 1998. 

Dr. Syn received his board certification from the American Board of Surgery as well as the American Board of Colon and Rectal Surgery. He has been practicing colon and rectal surgery in Southern California for over 20 years.

To schedule an appointment with Dr. Syn or another member of the team at Minimally Invasive Medical Group, call the office or request an appointment online today.

Dr. Ricardo La Grotta, MD is a primary care physician. He serves patients at HealthyU Clinics at our Chandler, Arizona clinic.

With over two decades of medical experience, Dr. La Grotta brings his passion and commitment to HealthyU Clinics. Motivated by the organization's dedication to prioritizing patients, he joins with enthusiasm and a belief that the clinic is truly upholding the oath in primary care by putting people first.

Having spent his formative years in diverse regions such as South America, the Caribbean, and the Pacific Northwest, Dr. La Grotta has cultivated a unique perspective. His focus on Primary Care and Urgent Care stems from a seamless blend of practical experience and scientific knowledge.

Although his family has been in the Pacific Northwest for four decades, Dr. La Grotta eagerly embraces Arizona as his new home. He looks forward to immersing himself in the beauty of the state, connecting with its vibrant communities, and indulging in the rich gastronomy that Arizona has to offer.

Dr. Kathy Zelken is returning as an aesthetic medicine provider after a hiatus since the birth of her daughters. She has served as the medical advisor of the Zelken Institute for Aesthetic Medicine since it was established in 2016. She has worked tirelessly in the background to ensure the highest level of excellence and quality in all aspects of patient care. She has had a keen eye for artistry since childhood, starting from being a classically trained artist. She graduated summa cum laude from the University of California Berkeley with a major in Molecular and Cell Biology and a minor in Art History. During medical school at the University of Texas Southwestern, she published papers with world-renowned plastic surgeon and former editor-in-chief of Plastic and Reconstructive Surgery journal (the top journal in the field), Dr. Rod Rohrich. Her meticulous nature, extraordinary calmness, and friendly demeanor gained from close to a decade of working as a board-certified pediatrician in Orange County and doing some of the most delicate procedures on tiny babies will put the most anxious patients at ease. She is thrilled to help patients map out a comprehensive treatment plan to achieve their individual aesthetic goals and explain various nonsurgical procedures in detail. Her patients love her and seek her out for neuromodulator and facial contouring injections, skin rejuvenation, laser treatments, and so much more.

Ella graduated in June 2025 from the University of California, Irvine with a Bachelor of Arts in Psychological Sciences. With an interest in both therapy and administrative work, she was drawn to Mind Health Institute, Orange County. Ella is excited to make connections with patients and give them the best possible experiences at Mind Health Institute, Orange County.

I have been in practice for 25 years. During that time I have treated thousands of clients with High Blood Pressure, Elevated Cholesterol and Diabetes as well as Depression and Anxiety and Painful Conditions. Like most physicians I would briefly recommend diet and exercise and then prescribe medication. Most of the time one medication was not enough and their conditions usually worsened over time. Now I offer a different approach. I emphasize the lifestyle changes that actually get to the root of these problems. I personally have been adjusting my lifestyle. I still take medications when my doctors prescribe them but through my Eating Habits, some moderate Activity and practicing Mindfulness I am decreasing rather than increasing medications. I lost 40 pounds, improved my Blood Pressure, corrected my Cholesterol and most importantly improved my Pain and Mood. I am passionate to help others achieve the results of their goals as well.

Dr. Kenna Schnarr is dual-boarded in Obstetrics and Gynecology and Family Medicine, bringing a comprehensive, patient-centered approach to women’s health. Originally from a small town with very few doctors, Dr. Schnarr values strong patient relationships and continuity of care. With training across both primary care and women’s health, Dr. Schnarr is committed to delivering comprehensive, holistic care to women at every stage of life — what she describes as “womb to tomb.”

She earned her medical degree with clinical honors from Kansas City University of Medicine and Biosciences, where she also completed a fellowship teaching anatomy and pathology to medical students alongside continuing breast cancer research. Prior to medical school, she earned a Master’s in stem cell and cancer biology, with research focused on using stem cells to treat triple negative breast cancer. Dr. Schnarr has authored multiple peer-reviewed publications and is passionate about mentoring, medical education, and interdisciplinary collaboration. Outside of medicine, she enjoys fitness, culinary exploration, international travel, and spending time with her spouse, family, and friends.