Brief Answer:
Sinusitis could be the reason of your problems

Detailed Answer:
Thanks for posting on HealthcareMagic.

I have gone through the question but unfortunately the information is not enough to make a diagnosis. But overall I find reasonable probability of your problems being caused due to your sinusitis.

* Generally getting the eye power checked is the first step to evaluating headaches.
* Sinusitis and rhinitis due to allergic cause is a common cause of headaches. Taking steam inhalation twice a day should be helpful in this regard. It is often associated with peri orbital pain as in your case. Sinusitis in generally difficult to treat because the sinuses have poor blood supply and the medicines are hardly able to reach there. This could be the reason of your problems persisting.
* I do not know what is the basis of assuming optic neuritis. I would like to know if it has been confirmed by an ophthalmologist.
* It is unlikely for the eyes to shrink. A clinical examination by an ophthalmologist should be helpful in this regard.

Regards
Dr. Kunal Saha

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