Shanti, aged 27 yrs presented with complaints of difficulty in reading near print. There is ptosis and diplopia in all directions. She is having-
III CN palsy
Myasthenia gravis
Presbyopia
VI CN palsy
Amongst the given options ptosis can be caused by 3rd nerve palsy and myasthenia gravis. However, in 3rd nerve palsy diplopia will not occur on Down & out gaze (due to sparing of SO and LR) while in myasthenia gravis, diplopia will occur in all directions.