20 years ago i was diagnosed with a growth restricting blood flow to my frontal cortex. the growth is at the optic chiasm. at the time they would have removed 1/2 my face to gain access. is there now an arthroscopic surgery to remove it?

If there is a lesion beneath the optic chiasm, it is most likely in the pituitary area, and this type of "growth" can be removed via the ethmoid sinuses, without major facial involvement. Get a referral to a university department neurosurgeon for a second opinion and up to date treatment options.

Agree with Dr Berryman, as I would interpret your post to suggest a pituitary tumor, but have no clue what you mean by "restricting blood flow to my frontal cortex" and "removed 1/2 my face". Suggest you update this by a visit to a neurosurgeon.