How to edit a recored that stores image address in a field

Hey guys.

I am working on edit page, i have a table like this :

Id, Title, ImageAddress

int, string, string

all are required.

I upload image in a folder and save its address in ImageAddress field.

So i have an action : Edit

now i have 2 options:

1- just editing title

2- edit title and ImageAddress

I am confused in first option, when user changes Title input and click on submit button how can i edit just Title? You know ModelState.IsValid will not allow me to set FileInput empty!

what is best solution?