You can use them but not easily with VFP.

The method would be to...
Store a general field in a temporary table.
Then do something like...

FUNCTION FiletoMemo
LPARAMETERS lcfilename,csomefield
*usage append blank
* Filetomemo('c:\test.jpg',"sometable.memofield")
lcimage=Filetostr(lcfilename)

*VFP
replace &csomefield with lcimage
*oracle
lcsql="update mytable set myfield="+ lcimage
SQLEXEC(h,"lcsql)
RETURN

******************************
FUNCTION MemotoFile
LPARAMETERS lcfilename,csomefield
*usage MemotoFile('c:\test.jpg',"sometable.memofield")
lcImage = &csomefield
StrToFile(lcfilename,lcfilename)
*!* lcImage = SomeTable.MemoField
*!* StrToFile(lcImage,"SOMEFILE.JPG")
*!* Image.Picture = "SOMEFILE.JPG"
RETURN


I haven't used it yet as I haven't yet required to store images in the database.
However, I don't see why this would not work.

I also think you need to call a DBMS_ procedure to load the blob field.
But can't recall the details on this.