Dear Magician:
Sorry to hear about your car accident. I don't think that the accident would have changed the epidermoid cyst, but there is always a possibility that trauma could have induced swelling of the area and therefore irritated the trigeminal nerve. The epidermoid cyst would be involved as it has taken up space or created a mass where one shouldn't be and therefore limited the space. Was there edema on the MRI that was noticable? Epidermal cysts can grow but usually they cause no problems when found by accident-please no pun intended.
Sincerely,
CCF Neuro MD