How to tell a Class 6 from a Class 7 pattern of balding

I’m not sure what Norwood level my uncle is as I believe I take after him. If I describe his hair loss stage hopefully you can help me determine if he is a Norwood 6 or 7 please. So my uncle has quite a large donor area on the back and on the side. On both sides of his head he has high parietal ridges but he is completely bald on top on his head I did see he has like 10 hairs still on top but they...

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