Match History
Instead of Luden's Echo you could also build a Liandry's Torment, Zhonya's Hourglass or Abyssal Scepter. This ofc depends on what the enemy team builds as well. In general if they have alot of AP, or your team does (and nobody made it yet), an Abyssal Scepter is a good idea.
Because my lane and teamfights went very well, I didn't go for the extra defense (Zhonyas/Abyssal) and started ROA before anything else. It gives you a good mana sustain, along with HP. After you get a Rylais Crystal Scepter as well, you have so much HP most of the enemy team will just ignore you and that gives you the opportunity to deal more damage and help your allies with survival and kills.
If you go Brand midlane, the enemy Brand build is pretty good for it. Ofc Void Staff instead of Boots is only something you should do if you're very certain about your own and your teams survival.