Optic Neuritis - this can cause sudden blurred or lost vision, and sometimes pain on eye movement. Scleritis - pain, blurred vision, redness. Temporal arteritis - headache with blurring or loss of vision, usually in the elderly. Thyroid related eye disease - scratchy sensation, double or blurred vision, protruding eyes. Uveitis - inflammation within the eye can lead to floaters, pain, and blurred vision.
Severe inflammation can cause a loss of vision due to inflammatory debris within the eye.