How to get the user image form user atrributes account

With Knack.getUserAttributes(); I can get all my current user attributes, but I have an Image field (avatar) in my user acount fields.

Knack.getUserAttributes(); show my image value with only the GUID image, and i can not read all image attributes like filename, url, thumb url... with object returned.

Any idea to load my current user file image value (url and thumb url) when my app is loaded?