Thomas Joseph, President & CEO

Thomas Joseph is President and CEO at Visiun. Joseph holds a B.S. in Medical Technology and an MBA in corporate finance from the University of Michigan. He was certified in Lean Manufacturing by the University of Michigan. He was certified in Lean Manufacturing by the University of Michigan’s College of Engineering in 2003.

Joseph is a seasoned consulting professional with 20 years of consulting experience and areas of expertise that include financial management, operations assessment and improvements using Lean strategies, as well as research and development. He has presented on financial management issues at national conferences and authored several articles in peer reviewed journals. Joseph’s work in process improvement has led to the development of Performance Insight, a business intelligence/analytics tool used by laboratorians to improve performance, quality, productivity and patient care.

Denis Burke, CTO

Denis Burke is responsible for product development and technology decisions at Visiun.  He has over 20 years of experience in nearly all facets of Information Technology from network engineering to database management to program management.  Probably more importantly, he has a passion for all things related to new technology.
Denis obtained a B.S. in Chemical Engineering from Michigan State University, as well as an MBA from the University of Michigan. He also holds (or did hold) industry certifications: CNE, MCSE, TOGAF, ITIL, and PMP.

Tim Bickley, MT(ASCP), MBA, CPHIMS, Vice-President of Sales

Tim Bickley is responsible for directing and coordinating company sales and marketing functions.  In addition, he is responsible for establishing new partnerships with prospects and growing relationships with existing customers.

Tim brings more than 20 years of laboratory sales and management experience to Visiun. He has a dedicated career within the laboratory healthcare market, which includes sales and implementation of laboratory medical devices and information system software throughout the US and globally. In his role as Director of Sales and Marketing, he also works closely with laboratory and hospital IT management. Prior to Visiun, Tim was Administrative Laboratory Director, Regional Sales Manager, and Strategic Account Executive for major LIS and laboratory diagnostic vendors.  He holds a BS degree in Medical Technology from the Medical College of Virginia/VCU, MBA degree from Averett University, and is a Certified Professional in Health Information Management Systems.

Denise Uettwiller-Geiger, Ph.D., DLM(ASCP), Advisory Board Member

Denise Uettwiller-Geiger, Ph.D., DLM(ASCP), is an award-winning Clinical Chemist, Director of Clinical Trials at John T Mather Hospital, and author of more than 80 clinical journal articles.  Dr. Uettwiller-Geiger works in a laboratory that processes more than 2.4 million tests per year, assists with new technology and menu expansion, and serves as principal investigator for clinical trials in the areas of infectious disease, cardiac, point of care, and other new technologies. She also provides expert education, guidance and consultation to clinicians. 

Dr. Uettwiller-Geiger received her Master of Health Sciences and an Advanced Certificate in Health Care Management, from the W. Averall Harriman School for Policy and Management, from Stony Brook University, Stony Brook, New York, and a PhD in Biomedical Science from Pacific Western University, Brentwood, California.  

Heather N. Signorelli, DO, Advisory Board Member

Dr. Signorelli is board certified in anatomic, clinical and chemical pathology. Her interests include clinical chemistry with emphasis on quality improvement and test utilization. Dr. Signorelli is currently the Chief Laboratory Officer for HealthOne/HCA in Denver where her primary focus is to lead consolidation, standardization and stewardship programs.

After earning a BS in biochemistry and molecular biology from the University of California at Santa Cruz, Dr. Signorelli received her medical degree in 2010 from Touro Osteopathic Medical University, Vallejo, CA. She subsequently completed her residency in anatomic and clinical pathology at the University of Colorado Anschultz Medical Campus, Denver, CO, followed by a felllowship in clinical chemistry at the University of Utah/ARUP Laboratories, Salt Lake City, UT.

Dr. Signorelli is actively involved with the College of American Pathologists (CAP).


 Dr. Jorge L. Sepulveda, M.D., Ph.D, Advisory Board Member

Dr. Sepulveda is a Professor of Clinical Pathology and Cell Biology at Columbia University College of Physicians and Surgeons and currently serves as the Associate Director for Laboratory Medicine and Medical Director of Laboratory Informatics at Columbia / New York Presbyterian Hospital in New York, NY.  As a clinical laboratorian and research scientist, his specialty focuses on using large-scale data analysis and computational approaches to understand and guide efficient use of clinical laboratory test to improve patient care. 

After earning his PhD in Cell and Molecular Biology from the Baylor College of Medicine in 1994, Dr. Sepulveda went on to complete an MD at the University of Lisbon in 1984.  His current research centers on Systems Biology approaches to understanding molecular mechanisms regulating cellular phenotypes, in particular focusing on the transformation from a physiologic to a pathologic state.  A particular angle of interest is the integration of large scale genomic, transcriptomic, epigenetic, proteomic, and metabolomic data to derive a molecular “holistic” approach to understanding the development of gastro-intestinal cancers (particularly of the esophagus and stomach) and in a separate project, the transition from a healthy heart to cardiac hypertrophy and heart failure.  The aim of this research is for a comprehensive, integrated view of pathology to develop personalized diagnostic, prognostic, and therapeutic approaches to disease.