Look at IF-MIB::ifDescr, it will contain the description of the interface.
As an example:
IF-MIB::ifDescr.6 = STRING: vlan1 IF-MIB::ifDescr.7 = STRING: vlan231 IF-MIB::ifDescr.8 = STRING: vlan232 IF-MIB::ifDescr.9 = STRING: vlan252 IF-MIB::ifDescr.2001 = STRING: ge1 IF-MIB::ifDescr.2002 = STRING: ge2 IF-MIB::ifDescr.3001 = STRING: radio1 IF-MIB::ifDescr.3002 = STRING: radio2 IF-MIB::ifDescr.3003 = STRING: radio3