I've seen well hydrated snakes with crinkly eyes...

But I've never seen a well hydrated snake display tenting of the dorsal skin along the spine.

I've seen dented/crinkly eyes in snakes with partially retained lenses. I've seen dented eyes in snakes that are kept in too arid conditions for the species. In short, I've seen multiple situations in which dented eyes are the result.

Tenting of the skin along the spine is the sure fire way to see if your snake is dehydrated.