A compound sheath (102) comprising: an endoscopic channel (110) arranged for accepting an elongated endoscopic imaging device (104)； a parallel use channel (106) arranged for accepting a catheter-based tool (112), and a multi-channel hub (114) comprising a connection port (116) that couples to the proximal end of the parallel use channel； a rinse port (118A) that couples to a fluid reservoir device that injects fluid； a withdrawal port (118B) that couples to a vacuum forming device that removes fluid； a tool port (118C) for passing a catheter-based tool； wherein the multi-channel hub (114) establishes a fluid channel for fluid communication between the parallel use channel (106) and the rinse port (118A) or the withdrawal port (118B), and a mechanical channel for passing therethrough a catheter-based tool between the parallel use channel and the tool port such that fluid from the rinse port or the withdrawal port and the catheter-based tool of the tool port are simultaneously passing all along the parallel use channel.
