I've viewed a few threads and was shocked to find that there has been no response or fixes for this, and the most oldest one was back in the Syndra patch, and even THAT did not have a fix.
I've experienced periodic game lag as well, the creeps would glide, my mouse input and character movement is delayed by 2-5 even 9 seconds periodically. I would see the little green marker when I click, but my Akali will not move. I also noticed that at the top right of my screen, 4 brown boxes would be brown at full force lag, and 1 box would be shaded as regular- no problems.
And to rub salt to wound, I would be raged by my team calling me noob and reporting me after the game, due to the fact that in a team fight, everything is going good and well and I would just drop dead and cost the game. This happens periodically. I'm an honorable person, I know my game strengths, but I am most certainly not a "noob." This is killing me.