Clinical Leadership Team

Meet Our Clinical Leadership Team

Dr. Michael A. Roman

Medical Director & Clinical Associate Professor – LDCI, MD, FRCPC, FCCP

Dr. Michael Roman is the Medical Director of Lung Diagnostic Centres Inc., as well as the Clinical Assistant Professor in the Department of Medicine at the University of Calgary. He is an attending respirologist at the Rockyview General Hospital and a member of the Rockview Respirology Consultants (R2C). Dr. Roman completed his medical degree at Western University and moved to Calgary to complete training in Internal Medicine and Respirology at the University of Calgary. Following his Respirology training, he travelled to Harbor-U.C.L.A Medical Center in Los Angeles to complete a fellowship concentrating on exercise physiology, clinical cardiopulmonary exercise testing and pulmonary rehabilitation.

Dr. Roman has an active inpatient and ambulatory clinical practice in general respirology. He is the director of the Regional Cardiopulmonary Exercise Laboratory as well as medical director of the C.A.R. Pulmonary Rehabilitation program. His research interests include exercise physiology, pulmonary rehabilitation and COPD management. He has an active role in undergraduate and postgraduate medical teaching.

Dr. Willis H. Tsai


Dr. Willis Tsai is the Medical Consultant for Lung Diagnostic Centres Inc, Sound Sleep Solutions and Maple Respiratory Group. He is also a Clinical Associate Professor in the Departments of Medicine and Community Health Sciences at the University of Calgary. He is a staff respirologist at the Rockyview General Hospital and Foothills Medical Centre Sleep Centre; as well as a member of the Rockyview Respirology Consultants (R2C). He received his medical degree from the University of Toronto, and is certified in Internal Medicine (University of Toronto), Respirology (Western University), and Sleep Medicine (University of Calgary). During post-doctoral research training in Sleep Medicine, he also received a MSc (Clinical Epidemiology) from the University of Calgary.

Dr. Manisha Witmans


Dr. Whitmans is the Medical Director of Sound Sleep Solutions and is a renowned Board Certified specialist who also subspecializes in pediatric pulmonology. Dr. Witmans completed her medical training at the University of Saskatchewan, her residency in Pediatrics and her fellowship in Pediatrics Respirology at the University of Calgary, Alberta Children’s Hospital. She subsequently completed additional fellowship training in Pulmonology and Sleep Medicine at the Children’s Hospital Los Angeles in California. After returning to Alberta, she developed the pediatric sleep program at the Stollery children’s hospital in Edmonton. Dr. Witmans is a passionate and driven professional who is striving to improve sleep and patient care for children and their families. She has helped with the development of the current international guidelines on the use of polysomnography in pediatric respiratory and non-respiratory sleep disorders.



Dr. Charkhandeh is the Clinical Director at The Snore Centre, and maintains a group of private practices in Edmonton and Calgary with an interest in Dental Sleep Medicine and TMD.

Dr. Charkhandeh received his Doctor of Dental Surgery (DDS) Degree and Bachelor of Medical Sciences from the University of Alberta, Canada. He is actively involved in clinical research in Dental Sleep Medicine and his research focuses on developing new technologies to improve treatment outcome predictability and patient selection in Oral Appliance Therapy for patients with OSA. He is the Chief Dental Officer at Zephyr Sleep Technologies, the developer of “MATRxTM” Technology. He is the recipient of the “2012 & 2015 Clinical Research Award” and “2015 Clinical Excellence Award” from the American Academy of Dental Sleep Medicine (AADSM).

Dr. Charkhandeh is a major advocate for the importance of a multi-disciplinary approach to Dental Sleep Medicine which focuses on the collaboration of Sleep Physicians, Sleep Dentists and other healthcare professionals. He has been treating OSA patients for many years and also has trained hundreds of dentists in Dental Sleep Medicine.