Apparatuses of the type broadly applicable to numerous medical applications inwhich it is desirable to insert one ormore steerable or non-steerable catheters or similar devices into a workingchannel of an associated device, such as an endoscope,catheter, etc., or passageway of a patient, are disclosed. The apparatuses mayinclude catheters (24) having a dedicated guide wirechannel (60) and one or more of the following: viewing capabilities, a workingchannel, and auxiliary channels (62, 64, 66), such asinsufflation/irrigation channels. The catheters may include a guide wirechannel that is configured to provide the catheter or otherdevice with rapid exchange capabilities.
