Meyer lemon tree lost leaves, branches still green
My improved meyer lemon tree is in container, and we brought it indoors for the winter. It did quite well for a few months and the last month it had a few problems, including fungus gnats, and it lost a lot of leaves. We got the larval fungicide and killed them and were able to move the tree back outside when the weather got better. We've had some decent weather yet, but I haven't seen any new leaf growth on my tree. I'm wondering if this tree has any hope of recovery? Any suggestions would be highly appreciated.
Here's a picture of the tree now.
A close up of some of the branches.