Lankinen, who represented the Rockford IceHogs at the 2020 AHL All-Star Classic, is 8-10-2 in 21 AHL appearances this season with a 3.03 goals-against average and a .909 save percentage.
The 25-year-old native of Helsinki, Finland, has a record of 15-18-6 (2.77, .909) in 40 career AHL appearances over two seasons. He helped Finland capture the gold medal at the 2019 IIHF World Championship.
Highmore has skated in 36 NHL games with the Blackhawks in 2019-20, collecting two goals and four assists. He also has four goals and eight assists in 21 outings with Rockford.
The third-year pro from Halifax, N.S., has totaled 31 goals and 33 assists for 64 points in 97 career AHL games, and was an AHL All-Star as a rookie in 2018.
He has skated in 49 games in the NHL with Chicago, notching four goals and four assists.