Lieuwen announced Thursday that he would "take significant time off" to recover from a concussion sustained last season, Bill Hoppe of the Olean Times Herald reports. Lieuwen sustained the concussion during a stint with the Sabres in April. He had been playing regularly for Rochester all season until suffering a hip flexor injury, but had been experiencing vision issues throughout. After a neurologist determined Lieuwen's brain never fully healed from the April concussion, the 23-year-old will take some time off until further notice. It's likely the vision problems had some impact in his downturn in performance for Rochester, as he posted a 3.29 GAA and .883 save percentage across 16 games.