Some radiation therapy patients report seeing flashes of light in front of their eyes during treatment – even when their eyes are closed. Now this long-standing mystery may have been solved, thanks to this weird effect being caught on camera for th
Some radiation therapy patients report seeing flashes of light in front of their eyes during treatment – even when their eyes are closed. Now this long-standing mystery may have been solved, thanks to this weird effect being caught on camera for the first time.
What’s happening, according to a new study, is that enough light is being produced inside the eye to cause these visual sensations. It’s what’s known as Cherenkov emissions or Cherenkov radiation, the same effect that causes nuclear reactors to glow blue when they’re underwater.
Models have shown that as the radiation beam passes through the vitreous fluid or the clear gel of the eye, light is generated, and the researchers have provided the direct evidence.
The discovery could help to improve future radiation treatments – and to put patients’ minds at ease about those flashing lights.
"Our newest data is exciting because for the first time, light emission from the eye of a patient undergoing radiotherapy was captured," says biomedical engineer Irwin Tendler, from Dartmouth College.
"This data is also the first instance of evidence directly supporting that there is enough light produced inside the eye to cause a visual sensation and that this light resembles Cherenkov emission."
The idea of Cherenkov emission in radiotherapy had already been put forward by scientists, but only alongside other hypotheses. To find direct evidence, the team behind the new study…
