Crown balding?

Hi,

I was wondering if my crown was balding. My temples have receded massively over the last year (NW2.5 -3), and I'm afraid it's coming to my crown as well. I'm starting a regime of nizoral 2% + minox 5% + dermarolling next week, should I include my crown in the minox and dermarolling as well? Can dermarolling be done on the crown? Thanks!