how to remove alternative text for images in my pdf.

hi everyone,

i was wondering how i can remove the alternative text in my pdf file, that appers when the mouse cursor is on the image?

i installed adobe acrobat pro 9. write all the text in microsoft office word 2007, add the images, create pdf and everythings ok, but this alternative text on the image (the alternative text is file's name, for ex. photo.jpg)

such a carking care.

thank you in advance!!

d.