Cassiopeia, Poison more Visible

I've been playing the reworked cassiopeia as top lane and I am REALLY enjoying her new kit. Being able to fit that extra damage item and building liandry + void staff + abyssal scepter allows her to completely wreck tanks/bruisers

The trouble I am having with her in team fights is that it is REALLY HARD to tell whether or not a target is poisoned for me to use my twin fang. Sure, its obvious right after I hit them with my Q.. but how long afterwards can I cast my E? Do i stop to cast my Q again after I cast my E 3 times? Seriously, I shouldn't have to squint to check if the enemy champ is poisoned in the middle of a hectic team fight.

Sometimes, the Q jus barely grazes the enemy champion and you don't know whether or not they are poisoned