Diagnosis - Severity of the Eye Disease
	This can be done according to the NO SPECS classification which serves as an ingenious memory aid for the clinical examination. Quantitative measurements should be recorded whenever possible to enable objective assessment (Pinchera et al. 1992) including: Eyelids: measurement of lid aperture and of the position of the eyelids in relation to the corneoscleral limbus (e.g. lid fissure measures 14 mm, upper lid is retracted 2 mm while lower lid is retracted 1 mm from the limbus). Proptosis: exophthalmometer measurements in mm. Extra-ocular muscles: quantitative measurement of eye movements (e.g. by Hess chart or a modified perimeter) (Mourits et al. 1994); presence or absence of single binocular vision with or without prisms in the central 30° of the visual fields. Cornea: presence or absence of exposure keratitis assessed with rose bengal or fluorescein. Optic nerve: measurement of visual acuity, with additional measurement of visual fields, color vision and visual evoked response in suspected cases. Because many patients do not complain of reduced visual acuity, the clinician should remain alert on the existence of optic neuropathy and should ask specifically for grayish vision and for blurred vision (blurred vision that does not disappear after blinking or after covering of one eye is suspicious).