It's possible but you need to experiment, here's why:
Test textures
As you can see the problem area is only 2 triangles big, so it's easy to avoid, I don't think anyone stopped to map it properly. If it's really necessary I can give it a shot though.
EDIT: Actually wasn't as hard as I thought, here is the perfect map:
You can clearly see in the screenshot that the blue edges are where the seam is, and the texture is actually mirrored so the pink edge goes around the outside, while the red edge is actually the very top of the head.
Some very strange mapping and I doubt this could actually be used for anything because of the extreme distortion, but there you go, that's how you map the top of a head.
EDIT2: actually I guess it's not perfect because I didn't write down where the seam between the top tris and the next row are, so you will have to figure out where that seam goes I guess lol...
Last edited by ImmortalPig; Apr 5, 2016 at 03:38 PM.