Software that provides a reliable second opinion to a radiologist reading mammograms could cut short the young practice of sending scans abroad to be read by cheaper radiologists in India and elsewhere. Given the accelerating trend to more powerful processors and more intelligent software, we predict it will not be long before the software will be more reliable than any human radiologist, whose first opinion will no longer be required.
The assault on Alzheimer’s continues to accrue new weapons sights, including a simple eye test and an enzyme biomarker either or both of which could have a profound effect in catching and slowing the disease at its earliest stages, and a possible simple blood test to predict dementia. The war on cancer is similarly aquiring new target acquisition technologies, including a proteomics-based blood serum test more sensitive and reliable than previous tests (but equally inexpensive), and DNA probes that could in principle not only reliably identify specific types of cancer cells in a patient but also carry a drug to destroy the identified cells without harming nearby normal cells. Othe diagnostics advances:
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Cancer Detection by Computer
Computer Aided Detection (CAD) software (which seems destined to be confused with the other CAD — Computer Aided Design — software) scans mammograms for any suspicious features that may indicate a tumour and then highlights the irregularities on screen. Cancer Research UK found that it reliably served as a second opinion for the radiologist — equivalent to having two radiologists study the same mammogram — and was sometimes even better. An epidemiologist for Cancer Research UK told the BBC News: “The great advantage of CAD is that, if we confirm the very promising results of this study in a prospective trial, it could help manpower problems in the breast screening service. The CAD system would free-up hundreds of radiologists to work on more mammograms as only one instead of two would be required to work on each X-ray.” US researchers have developed a set of DNA probes which only stick to cancer cells, enabling them so far to distinguish leukaemia cells from healthy ones. Hundreds of different probes were labelled with a fluorescent protein, so the researchers could identify which ones stuck only to proteins found on the surface of cancer cells. They could thus identify cancer cells more accurately than could be done by the human eye using a microscope. The researchers are now trying to develop probes for specific types of cancer cell, in order to diagnose cancer sub-types. They could identify slight individual differences among cancer patients and facilitate more custom-tailored treatment. It might also be possible to attach a drug to the probes. Researchers from the Netherlands’ Erasmus Medical Centre have discovered that blood levels of two amyloid proteins important in Alzheimer’s disease may predict pending dementia, though more work is needed before these markers could be used as a dementia blood test. High levels of one protein (Aß1-40) and low levels of another (Aß1-42) were linked with a more than 10-fold increased dementia risk among 1,756 people known to be at risk for dementia. Over eight years of study, 392 of them developed dementia. The problem, according to an Alzheimer’s Society official, is that “the magnitude of difference is not proficient to provide a reliable diagnostic test.” Nevertheless, he said, the research was “extremely encouraging.” Laser Eye Imaging Reveals Alzheimer’s With a brief and harmless pulse of infrared light (technically, “quasi-elastic light scattering”) researechers at Brigham and Women’s Hospital have detected deposits of beta-amyloid — the protein that builds up in the brains of Alzheimer’s sufferers — in the eye lenses of of mice with the disease. The test could be used to detect the disease at its earliest stages as well as to track disease progression and monitor how people respond to Alzheimer’s treatments, says a BBC News report. Much more work is needed to show exactly how the amount of protein in the eye relates to development of dementia before such a test could be available to use in patients. The discovery of enzymes that react abnormally only in the skin of Alzheimer’s patients could lead to a quick, painless skin test for the disease, rather than the psychiatric assessments or post-mortem examinations currently the only options. The test worked well on tissues taken from human cadavers, and can distinguish Alzheimer’s from other neurological conditions such as Parkinson’s. The enzyme biomarker was most pronounced in samples from people at the earliest stages of the disease, as opposed to those whose condition was more advanced. This high level of initial specificity would be particularly helpful in any early diagnostic test. Early diagnosis is important because drugs that can slow the disease are most effective in its earliest stages. An Alzheimer’s Society researcher told the BBC News that “If the skin test can be successfully developed it will revolutionise early diagnosis of dementia.” More Sensitive Serum Blood Test University of Pennsylvania scientists have discovered a way to make an existing blood serum test more sensitive and able to detect minuscule amounts of proteins that could prove to be indicators for certain cancers. The use of proteomics to detect diseases (by searching for protein markers) has sometimes proved unreliable. When a blood test is done, some proteins have proven to be present in both cancer patients and in healthy people, while other proteins are associated with unrelated diseases. The cost of the new test will likely not be much more than the existing one, which can be as low as US$20. University of Wisconsin-Madison researchers are developing an MRI scanner which, rather than collecting data in a horizontal sweep across a body region, performs more efficient radial scans that allow physicians to “visualize in any plane in about the same time as [standard MRI scanners] are doing one plane,” as a university press release put it. Conventional MRI scan times are lengthy because “a lot of time [is] spent either prepping for the experiment or returning [the scanner] to the steady state” before performing the next experiment. The new scanner decreases the procedure time because it acquires data throughout the entire scan and is able to encode data in milliseconds. In addition, standard MRI scanners assemble images from a series of two-dimensional slices, rendering images with “high resolution in a single plane [but] poor resolution” in the third dimension; the new scanner’s radial signals render more precise, high-resolution, three-dimensional images. The new approach is being tested for knee scans, but its speed could benefit the imaging of highly mobile organs, such as the heart or abdomen. Microsoft’s new Photosynth software, expected to be available later this year, analyses collections of photographs for similarities then reconstructs them in 3D, allowing users to view or “fly” through a scene from any angle. The photographs may be taken from different cameras at different times. Photosynth picks out distinctive features in each image and cross-references them against the other photographs, checking for similarities. This allows it to pinpoint a feature’s 3D position and to also calculate where the position of the camera would have been when the picture was taken. The prototype can use as few as two pictures, but several dozen are better. Photo-sharing websites will likely be early adopters of this technology. Other obvious users are the tourism, hospitality, and real estate industries. |