Approach to a patient with blepharoptosis.

Blepharoptosis or drooping of upper eye lid is a common, but non-specific sign of neurological diseases which sometimes could herald a life-threatening disorder. First, the diagnosis of ptosis should be established by considering four clinical measurements: palpebral fissure height, marginal reflex distance, upper eyelid crease, and levator function test. The diagnostic categories of ptosis are scheduled as pseudo-ptosis, congenital, and acquired ptosis. Acquired causes include mechanical, myogenic, neuromuscular, neurogenic, and cerebral. Each category with diseases presenting with ptosis was described in detail. Considering some features, such as involvement of other cranial nerves, extraocular muscle, pupil size and reactivity, and unilateral or bilateral presentation of ptosis, could help to narrow the differential diagnosis.