what can cause pain in the eye
1 The nerve travelling from the back of the eyeball into the brain can become inflamed. Multiple sclerosis or other autoimmune conditions or infections are often to blame. Symptoms include eye pain and loss of vision.  Sinusitis can create pressure behind the eyes, causing eye pain on one or both sides.
1 A sensation of grit in the eyes, and sometimes pain, result.  A stye -- also known as a hordeolum -- is an infection or inflammation of the eyelid margin that can come from the hair follicles of eyelashes or from oil glands. A stye is often painful and most often caused by infection.