C# - How to not redraw image each time picture box is repainted

C# - How to not redraw image each time picture box is repainted

I have a picture box with some images that never need to move. It's for a
map designer. The user chooses how many columns and rows the map will
have, then it gets drawn as a line grid, and i have a mouseMove method
because when the user hovers over the edge of a cell it needs to highlight
red. So the map is being repainted continuously, very fast, when the mouse
is moving. This was no issue when i just had drawLines on the map for rows
and columns. But now that i just added a cell background image, the cell
background images flicker on mouse move as they are being redrawn too
fast.
Any help appreciated. Thanks.