The different parts of a health care system have different focuses. A hospital's stroke （中风） unit monitors blood flow in the brain. The cardiac unit is interested in that same flow, but through and from the heart. Each collection of equipment and data is effective in its own field. Thus, like the story of blind men feeling an elephant, modern health care offers many separate pictures of a patient, but rarely a useful united one.
On top of all this, the instruments that doctors use to monitor health are often expensive, as is the training required to use them. That combined cost is too high for the medical system to scan regularly, for early signs of illness, so patients are at risk of heart disease or a stroke.
An unusual research project called AlzEye, run by Moorfields Eye Hospital in London, in cooperation with University College, London (UCL) , may change this. It is attempting to use the eye as a window through which signals about the health of other organs could be discovered. The doctors in charge of it, Siegfried Wagner and Pearse Keane, are studying Moorfields' database of eye scans, which offers a detailed picture of the health of the retina (视网膜).
The project will go a step further：With the information about other aspects of patients' health collected from other hospitals around England, doctors will be able to look for more accurate signs of disease through eye scans.
The Moorfields data set has lots of linked cases to work with--far more than any similar project. For instance, the UK Biobank, one of the world's leading collections of medical data about individual people, contains 631 cases of a "major cardiac adverse event". The Moorfields data contain about 12, 000 such. The Biobank has data on about 1, 500 stroke patients. Moorfields has 11, 900. For the disease on which the Moorfields project will focus to start with dementia, the data set holds 15, 100 cases. The only comparable study has 86.
Wagner and Keane are searching for patterns in the eye that show the emergence of disease elsewhere in the body. If such patterns could be recognized reliably, the potential impact would be huge.
