Visual sensations during megavoltage radiotherapy to the orbit attributable to Cherenkov radiation

摘要: During megavoltage photon and electron beam radiotherapytreatment involving the eye, patients commonly report visual sensations; “nerve stimulation” is conventional explanation. We propose that phenomenon can be attributed to Cherenkov radiation inside eye. The threshold energy for in water 260 keV . human retina able perceive approximately 5–14 visible photons 0.001 s A single 500 traversing 1 mm of will induce nearly 15 range photons. a portal image eye produce sufficient detected by retina.