I am so sorry to hear about your serious illness and how it was diagnosed.
Thank you for taking the time to detail it and place it here as a warning to everyone on this site.
I too have these ridges and wondered what they were caused from.
I'm five years older than you. What a terrible shock you must have received. How are you doing now? If you ever need to email me, please feel free. jeweldee@xnets.co.za. I'd be happy to keep in touch with you and offer what support I can.
One never knows what tomorrow will bring, do we?