[MacDV] Burning CD's

[tucker ian]

I realize this is OT, but I would like some advice please.

I always save a copy of any upgrades etc. by burning same to a CD in  
Toast Titanium 6.   I usually add several "Sessions" to the one CD.

Recently, in a hurry, I burnt additional sessions to two CD's and  
instead of selecting "Data" in the Toast window I accidentally left  
the settings on "Video" and now one CD will only allow me to access  
the most recent Session and the other, the first Session.

Is it at all possible to retrieve the information stored in the other  
Sessions ?

TIA,

Ian T.