Painful eye movement is a feature of?

Ans. is 'a' i.e., Optic neuritis Clinical features of Optic neuritis* The condition is usually unilateral, except in toxic amblyopia. Major symptom of optic neuritis is profound vision loss and central vision is affected very early (in contrast to papilloedema). There is monocular sudden, progressive and profound loss of vision. The visual impairment is accompanied by disturbance of other visual functions such as loss of color vision (typically red desaturation) and reduced perception of light intensity. Occasionally patients may observe an altered perception of moving objects (Pulfrich phenomenon) or a worsening* of symptoms with exercise or an increase in body temperature (Uhthoff sign).* There is pain behind the eyeball, particularly in reterbulbar neuritis in which there is pain on eye movements, especially in upward and downward direction due to attachment of some fibres of superior rectus to the dura mater.* Visually evoked response (VER) shows reduced amplitude and delayed transmission time.