I can.t help thinking that there may be touch of journalistic bullshit here. I am sure that if someone had lost the sight in one eye due to an object thrown in the stadium it would have been all over the TV and internet. The article doesnt specify from which supporters the object was thrown either. Given Liverpool fans have an unrivalled talent when it comes to playing the victim I am sure we would have heard much much more about it than we have.
As for pie throwing, it is an ancient art that has been practised at football stadiums for decades. I myself took a direct hit on one occasion at Millwall,s old Den. Pastie of some kind right on the side of the bonce. A good mate of mine was hit by one at Crewe Alex a few years back, and indeed Mark Lawrenson ended up wearing a pie outside the millenium stadium following Newcastle getting humped by the rags in the cup semi-final a few years ago. By all accounts a fantastic long distance throw delivered by a "not best pleased" Geordie.