Akali shroud graphics not displayed [Gameplay]

I played against an Akali who put down her shroud on top of the wall directly in front of blue side blue buff. I didn't know it was there until "slowed" appeared over my character. Having next to zero warning my squishy mid lane annie was dead before I could even get a stun off. Same thing seemed to happen at the red side blue buff later, but in the chaos of the team fight I can't be sure.