@bruceg
Good morning,
I’m sorry to hear of your seizure disorder. At least half of Epilepsies are Idiopathic (Unknown cause) and the actual cause unfortunately is seldom identified.
Did you have any seizures during surgery? If not, how long after it did they start? What type seizures are you experiencing and how often? What med/s are you on? Are your seizures controlled with the meds/s?
If the seizures started after the surgery, I wonder if it was coincidental or may be somehow related to the Anesthesia? I know some Anesthetics are prone to cause seizures
I’ve had Generalized Idiopathic Epilepsy for 52 years and it wasn’t controlled until 6 years ago.
Here are some Epilepsy sites, one informational and the others are forums.
I wish you luck in your journey,

Coping with Epilepsy
https://www.coping-with-epilepsy.com/forums/
Epilepsy Foundation
https://www.epilepsy.com/forum-topics
Epilepsy Action Forum 4e (UK)
https://forum.epilepsy.org.uk/
Epilepsy Society (UK) Informative site
They discontinued their forum.
https://www.epilepsysociety.org.uk/facts-and-statistics#.XObS9BZlDDs
Jake