Team of Experts

Our multidisciplinary team is composed of board-certified surgeons and physicians, clinical psychologist, registered dietitian, program director, clinical liaison and patient coordinator.

They're committed to helping make your weight loss a permanent success through preparation, support and follow-up care.

Our team of experts includes:

Frederick M. Tiesenga, M.D.

Dr. Tiesenga is the medical director of bariatric surgery. He received his medical degree from the University of Illinois, College of Medicine, and performed his residency clinical training at Metropolitan Group Hospitals in Chicago. Fellowship-trained in laparoscopic gastric bypass, Dr. Tiesenga is an affiliate surgeon of the American Society of Bariatric Surgeons and a U.S. Surgical Proctor for Bariatric Surgery.

Stoyan Ivanov Kokocharov, M.D.

Dr. Kokocharov, board-certified surgeon, received his medical degree from the Medical University of Sofia, Bulgaria, and performed his residency clinical training at Grand Rapids Medical Education and Research Center in Michigan. Dr. Kokocharov is an associate of the American Society for Bariatric Surgery and fellow of the International College of Surgeons and the American College of Surgeons. He is a published author and presenter on obesity and bariatric surgery, and he speaks Bulgarian, Russian and Serbo-Croatian. Dr. Kokocharov previously served as medical director of bariatric surgery at Bariatric Solutions, Findley, Ohio.

Alexandra B. Roginsky, M.D.

Dr. Roginsky, board-certified surgeon, received her medical degree from the Feinberg School of Medicine, Northwestern University, Chicago, and performed her residency clinical training at the Medical College of Wisconsin. She is fellowship-trained in minimally invasive and robotic surgery, University of Illinois College of Medicine, Chicago, and served as a post-doctoral fellow at Northwestern University's Feinberg School of Medicine, where her research fellowship focused on cell cycle and cancer.

Anna Maria Wegierek, PsyD

Dr. Wegierek is a clinical psychologist. She provides the preoperative behavioral health assessment to help identify psychosocial risk factors and make recommendations aimed at ensuring the best possible outcome for the patient. She also provides postoperative follow-up care as needed.

Liliya Bursak, R.D. M.S.

As a registered dietitian, Liliya assesses nutrition and exercise behaviors, nutrition knowledge, the ability to self-manage a diet, and the level of understanding regarding postoperative diet requirements. She also provides preoperative and postoperative nutrition counseling.

Sherry Chillis, R.N., M.B.A.

As the bariatric program director, Sherry has more than 12 years of surgical nursing experience, including four years as nurse manager of the hospital's Surgery Department and four years as director of the department, her current position. Sherry assists all patients in achieving their goals by guiding them through every step of the bariatric process and collaborating with the surgeon throughout the process.

Laura Buenrosto, R.N., Ph.D.

As the clinical liaison, Laura is the 'go to' person for patients throughout the bariatrics process from pre-surgery through post-surgery and beyond. She coordinates appointments, checks on follow-through and verifies follow-up tests. With a Ph.D. degree in clinical psychology and a doctoral dissertation on obesity, Laura is well suited as a 'life coach' in helping patients psychologically, emotionally and physically from getting ready for surgery to making life choices post-surgery. She also will coordinate the monthly support group.

Cecilia Hernandez

As the bariatric patient coordinator, Cecilia guides you through the pre-surgical requirements and insurance verification process. In addition, she coordinates post-surgical follow-up care.

Call 877-RES-INFO for Nurse Advice, Doctor Referrals or Class Registration Monday - Friday 8 am to 8 pm • Weekends 8 am to 4pm

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