Akiyama is surely a very particular character in the manga or in the drama, because his most attractive skill is his smartness, he has always been a genius.
But manga and drama versions show a different Akiyama.

In the manga he's a sort of golden boy that life hurted forever with his mother's horrible death. Here, he can't talk about that episode that is the begin of the darkest arc of his life, because in order to avenge her, he remains many years in prison.
One difference is here: in the manga we find the truth after a lot of chapters, so we don't know Akiyama's motivation for long time. In the drama he reveals it to Nao since the first moment, and she knows much more about him.

Even the personality and the role are different. In the manga he plays the Liar game just because he knows that it's a game that doesn't comport a real crime, in the drama he plays in order to save Nao but he's a pretender!

Another difference is Akiyama's introspection. We know him well in the manga but we can't understand much in the drama. It's short (just 11 episodes) and the episodes don't show all the sides of his personality.

He's always a fantastic character but I think that in the manga version he could be considerated "the real Akiyama".