Problem with a Japanese maple
It's difficult to see exactly what is going on with the tree. The branches in the first two photos look like them may well be dead. When (if) the tree puts out growth this spring, prune off any dead branches, leaving the raised branch collar (i.e. not flush with the trunk or leaving a stub).
It may be helpful to send us photos after the tree has leafed out. We need to see a shot of the entire tree as well as closer shots.