Ptosis and underaction of the superior rectus muscle.
It is suggested that the association of ptosis and superior rectus muscle underaction is most likely due to the common embryological origins of these two muscles from the same superior mesodermal complex.
D001763:Blepharoptosis / Q000196:embryology* / Q000503:physiopathology; D006801:Humans; D024510:Muscle Development; D009801:Oculomotor Muscles / Q000196:embryology* / Q000254:growth & development / Q000503:physiopathology