I think with a breed like Cavaliers, with so many inherited and commonly found diseases (MVD, CM/SM, pancreatitis, luxating patellas, PSOM, epilepsy, deafness, dry eye, myoclonus etc - and degenerative myelopathy has recently been added to the list), that insurance is essential. Or, as some people do, putting the equivalent amount away in a bank account every month. If you insure, make sure you get a lifetime policy.
In the UK a mini MRI scan (just head and neck, but enough for a diagnosis) costs around £250. A full scan is a round £1500 - £2000.
Our very special dogs don't come cheap!
Kate and Ruby