Hi everyone, thanks for this forum.  My sister has had the markers and is due to commence proton beam radiotherapy in Liverpool in a few weeks.  She was told that she would loose the sight in her eye as the melanoma is on the optic nerve.  Anyone any information on this?  will she definitely lose the sight in that eye or could it be just reduced but not completely gone?  i appreciate that there are varying outcomes with each individual but any information would be helpful.  And she is very stressed about going through the mask fitting and getting the PB so any advice regarding this for her?  Thanks in advance Audrey from Ireland