Biomedical engineers at Duke University say they have devised a new imaging device capable of measuring both the thickness and texture of the various layers of the retina at the back of the eye. The advance could be used to detect a biomarker of Alzheimer’s disease, potentially offering a widespread early warning system for the disease, according to the team which published its study “Multimodal Coherent Imaging of Retinal Biomarkers of Alzheimer’s Disease in a Mouse Model” in Scientific Reports.
“We acquired depth-resolved light scattering measurements from the retinas of triple transgenic Alzheimer’s Disease (3xTg-AD) mice and wild type (WT) age-matched controls using co-registered angle-resolved low-coherence interferometry (a/LCI) and optical coherence tomography (OCT). Angle-resolved light scattering measurements were acquired from the nerve fiber layer, outer plexiform layer, and retinal pigmented epithelium using image guidance and segmented thicknesses provided by co-registered OCT B-scans. Analysis of the OCT images showed a statistically significant thinning of the nerve fiber layer in AD mouse retinas compared to WT controls. The a/LCI scattering measurements provided complementary information that distinguishes AD mice by quantitatively characterizing tissue heterogeneity,” write the investigators… Continue reading.
After demonstrating that light accurately detected pre-cancerous cells in the lining of the esophagus, Duke University bioengineers turned their technology to the colon and have achieved similar results in a series of preliminary experiments.
This technology could be a non-invasive way for physicians to detect abnormal cells, or dysplasia, which have the potential of turning cancerous. These cells are in the epithelium, or lining, of various tissues, including the esophagus and colon.
Current biopsy techniques require physicians to take many random tissue samples, and for some disorders of the colon, these procedures can be disfiguring and life-changing. Instead of taking tissue samples, the new system would aim short bursts of light from the tip of an endoscope at locations suspected of having disease.
“When light is directed at these tissues, it scatters,” said Adam Wax, Theodroe Kennedy associate professor of biomedical engineering at Duke’s Pratt School of Engineering, who developed the device. The results of the Duke team’s preliminary experiments were reported online in the Journal of Biomedical Optics. “We can collect and analyze that scattered light looking for the tell-tale signs of dysplasia. Significantly, the technique is noninvasive so no tissue is taken and no dyes or contrast agents are needed.”
A tiny light source and sensors at the end of an endoscope may provide a more accurate way to identify pre-cancerous cells in the lining of the esophagus.
Developed by biomedical engineers at Duke University and successfully tested on patients during a clinical trial at the University of North Carolina at Chapel Hill, the device holds the promise of being a less invasive method for testing patients suspected of having Barrett’s esophagus, a change in the lining of the esophagus due to acid reflux. Acid reflux occurs when stomach acid splashes, or refluxes, up into the esophagus.