Russia doesn't make itself an easy holiday destination, that's for sure. Getting a visa for your time in Russia is a necessary evil and something I will explain and advise you on this blog entry.
You have to get a visa to visit Russia and these come in 90-day Business types or 30-day Tourist types. Your treatment in Russia will last 30 days at most. The only thing to consider is whether you think something might go wrong with your treatment might have to stay in Russia more than 30 days. This was my thinking and so I decided to get a 90-day visa. Just in case.