retro-orbital and sinus pain

I have been sufering from continuous left-sided retro-orbital and sinus pain for ten years that has now become disabling.  The pain is dull and aching in nature, 24 hours a day with no respite (greatly aggravated by eye movement).  Every conceivable imaging test has been negative (brain, orbit & sinus MRI's, CT), every kind of diagnostic or therapeutic nerve block has been useless, every type of medication (NSAIDS, anti-depressants, anti-spasicity, anti-convulsant) has been ineffective.  Every kind of specialist has been consulted, to no avail.
I now believe the pain originated from an upper left molar (#14) that was insufficiently root canalled 11 years ago.  One canal was overlooked.  I had the tooth pulled six months ago, and a large, infectious granuloma cyst was discovered and cleaned out. I believe a pain pattern has developed up through my left sinus and behind my left eye during the ten year period that this canal went undetected.
My question is:  Since medications and nerve blocks are ineffective, what kind of surgical procedure can be done at this point to relieve the pain?  While this is obviously not trigeminal neuralgia, could a diagnostic block (and subsequent lesioning) of the ophthlamic division of the trigeminal nerve help, since it is in the same area of pain distribution?  Any other suggestions?  Desperate for help.

[CCF-Neuro-M.D.-JT]

Sorry to hear about your pain.  If this is not trigeminal neuralgia as you say, then surgical treatment of your headache with "lesioning" of your trigeminal nerve is not indicated and could be dangerous. If an abnormal blood vessel is pushing against your trigeminal nerve as seen on MRI, then there can be vascular decompression done or even radiotherapy  (gamma knife) for trigeminal neuralgia. But again, if doctors don't feel this is tigeminal neuralgia, then those are not good options for you.

An older treatment for migraine headaches involves placing a Qtip that has been dipped in lidocaine (an anesthetic) into your nose to theoretically block the pain receptors on the side of the headache.  Although I have never personally used this or seen this done, my former mentors report some success with this treatment.  Good luck.

[BonnieBee]

A related discussion, Cluster headache from sinus blockage. was started.