Influence of reference nozzle choice on spray drift classification

A Y-adaptor manifold assembly includes a main tubular segment adapted to be coupled to an intravascular catheter. A first, tubular side port is joined to the main tubular segment so as to be in fluid communication with a through passage of the main tubular member. The first side port forms an infusion port for radiopaque dye. A second, tubular side port is joined to the main tubular segment so as to be in fluid communication with a through passage of the main tubular member. The second side port and main tubular segment are adapted to receive dilatation catheters. To prevent backbleeding, the second side port and main tubular segment include passive hemostatic valve mechanisms. Each valve mechanism includes a valve member and a disk valve. The valve member has a normally closed, sealed state, an open state and an in-use sealed state. The valve member has an inherent tendency to move to its normally closed, sealed state or its in-use state (wherein the valve member conforms about the dilatation catheter). Application of a compressive radial force moves the valve member to its open state.