Question: Hi. I am male, early 40s, generally very healthy. I suffer daily from nasal and facial pain, usually starting in the left side of my nose and progressing to the left side of my face. Right side is never affected. The pain starts every day when I enter the air-conditioned office at work, but can also be triggered by pollutants such as smoke. The pain diminishes when I leave the office, but does not disappear entirely.
Some history: Until about 20 years ago I never had any nasal problems. And then I had a cold, followed by sinusitis which caused stinging pain below both eyes - I think maxillary sinus area. After a week or so, the pain on the right side disappeared, but the pain on the left persisted. This did eventually stop, but I then had a period of about 3 years with regular sharp pain in the inside corner of my left eye (lacrimal sac / lower ethmoid sinus area). Antibiotics had no effect, and nasal endoscopy revealed no abnormalities. Eventually the pain went away, but reappeared intermittently for short spells triggered (I think) by dry or smoky air. Not sure if it's relevant, but I also suffer from hayfever in the summer (and have always done so). No other allergies that I'm aware of.
And then about 3 years ago, I moved to a new (sealed and air-conditioned) office at work. Within 15 minutes of entering the room for the first time, I began to get the familiar pain in the left side of my nose, and during the day the pain spread across my face. I have since moved to another office, but the problem persists. The pain often diminishes overnight when I am sleeping, but returns the next day.
One thing I have noticed is that the skin between the corner of my left eye and my nose (where the pain first originated) seems to protrude very slightly. If I hold my nostrils closed and inhale, the skin gets sucked inwards to become the same as it is around the other eye. Similarly if I breathe out with my nostrils closed, that area swells. The effect is small but perceptible, and is left-side only.
I have had another nasal endoscopy, which again revealed nothing abnormal. I have tried antihistamines and beconase nasal spray (beclometasone dipropionate), and also a capsaicin (pepper) spray. Steam inhalation and massage of the area may help very slightly. I have been on low dose amitriptyline for pain management for the last couple of years. The amitriptyline I think helps a bit. I use a pure saline nasal spray every hour or so at work, which definitely helps a little bit in the short-term, particularly with a prolonged spray action and holding my head upside down. Lunchtime also helps, maybe due to chewing/swallowing actions. The only time I have no pain at all is if I have a heavy cold with runny nose - this miraculously causes all symptoms to disappear, however it does cause a bit of postnasal drip when sleeping, such that I wake up coughing.
I'd be grateful for any opinions or advice! I'm also unsure whether top of nose/corner of eye falls under ENT or opthalmology.

Thanks for the quick reply. I've uploaded an image here:
http://www.healthcaremagic.com/MultiAction?task=documentAccess&documentId=149045

I should add that when I inhale strongly, my left nostril always closes completely.
Also sometimes I can extract a lot of thick, clear mucus from the left nostril, which relieves the symptoms somewhat. This can happen after steam inhalation, saline spray or capsaicin spray, or at other times.
There is also often a feeling of pressure, which makes me think that the pain is caused by a build up of mucus on the left side.

Thank you very much - one final question regarding the vitamin B12. I have been vegan for the last 5 years, and B12 is not found in the vegan diet. Could this be making the problem worse? I do have soya milk which has B12 added, but this may not be sufficient - my total current B12 intake is about 5-10 micrograms per week. What is the significance of B12? Thanks!

Also before being vegan, I was vegetarian for 20 years.

Thanks so much for your assistance, much appreciated.