Updating a .Response-list without having to close and reopen the document

I am currently working on a document storage application and i’ve encountered a problem. I use the $VersionOpt field to save the old versions of the document. To keep the application from overflooding i have a function that checks how many versions the document has and deletes all but the 4 most recent.

To get the versiondocuments i use the document.Responses method which i store in a document collection. This works fine except that no matter how many times i save a new document the .Responses method won’t return a value unless i close the document and open it again.

Why is this and what can i do to get around it?