He earned his medical degree and completed an internship at the University of Kentucky before embarking on a neurology residency at the University of Michigan, where he served as chief resident and completed a fellowship in neuroelectrophysiology and epilepsy. Board-certified in psychiatry and neurology, Twyman has written chapters in several books and published numerous articles in peer-reviewed medical and scientific journals.

The Alzheimer's Association estimates that 5.7 million Americans live with the disease today, and that number is expected to reach nearly 14 million by 2050. This urgency and the devastating effects the disease has on patients, families and society are fueling efforts of scientists and pharmaceutical companies to develop technologies for early diagnosis and treatment.


Positron emission tomography, or PET scans, and cerebrospinal fluid analysis are currently used to detect amyloid for clinical trials and as an aid in the diagnosis of Alzheimer's disease. These procedures are invasive, inconvenient and costly for clinical trial recruitment, and they are impractical for routine screening, disease monitoring and evaluation of therapy response.

The retina, the light-sensing structure at the back of the eye, is a developmental outgrowth of the central nervous system and shares many of the brain's characteristics, enabling the potential for amyloid detection from retinal imaging.

Research at Cedars-Sinai Medical Center in Los Angeles, led by Keith L. Black, M.D., and Maya Koronyo-Hamaoui, Ph.D., found that noninvasive retinal imaging could identify amyloid beta plaque in the retina in transgenic mouse models, and reported that amyloid beta plaques identified in human cadaver eyes were consistent with brain pathology. Recent studies by this group found that amyloid beta plaque that accumulates in the brain also builds up in the retina and shares similar plaque structure and other characteristics. NeuroVision holds the exclusive worldwide license to this technology, which is owned by Cedars-Sinai.


About NeuroVision Imaging Inc.
NeuroVision (www.neurovision.com) was formed in 2010 and is headquartered in Sacramento, California. The company is developing digital imaging and diagnostic solutions for identifying retinal pathology related to Alzheimer's disease (AD). In a study published in Neuroimage by members of NVI's founding team, under the direction of Keith L. Black, M.D., and Maya Koronyo-Hamaoui, Ph.D., noninvasive retinal imaging was shown to identify amyloid beta plaque in the retina in transgenic mouse models, and amyloid beta plaques were identified in human cadaver eyes consistent with brain pathology. Subsequent work published in JCI Insight found that amyloid beta plaque that accumulates in the brain also builds up in the retina and shares similar plaque structure and other characteristics. NVI is building upon this research and has developed proprietary image processing and machine learning algorithms to quantify eye pathology as an assessment of amyloid status in the central nervous system. The company's goal is to develop an easy-to-use, affordable and widely accessible product that helps identify those who may be affected by Alzheimer's. Black, the company's chairman and co-founder, is an internationally recognized neurosurgeon, researcher and thought leader in areas of brain and blood-brain barrier function, enhancing the therapeutic effects of treatments in the brain, and optical imaging of the brain. He is the chair of Cedars-Sinai's Department of Neurosurgery. Steven R. Verdooner, NVI's CEO as well as a company director, is an experienced medical technology industry veteran who has successfully developed, commercialized and marketed ophthalmological imaging and measurement systems for other diagnostic applications.

Back to HCB News

More People on the Move