Abstract: An angiographic syringe and plunger therefor, having utility in a power-driven angiographic syringe injector apparatus comprising an axially extending drive shaft and a frustoconical-shaped driving head attached to the shaft. The plunger is constructed to engage the driving head, with a circumferentially extended array of circumferentially spaced-apart flexible resilient engagement members which compressively bear on the side and rear surfaces of the frustoconical driving head. The flexible resilient engagement members are radially inwardly offset from the edge of the plunger, to avoid contact with inner surfaces of the syringe barrel contamination of the interior volume of the syringe. The syringe is mounted on the injector apparatus by a face plate adapter assembly serving to position the flexible resilient engagement members for coupling to the driving head.

Abstract: A plunger having a generally converging distal portion, and a rear face on which is provided a coupling structure. The coupling structure is transversely engageable by, and transversely disengageable from, a driving mechanism of a power-driven angiographic syringe, and, one engaged, cannot be disengaged by rotation of the driving mechanism relative to the plunger in the absence of translational movement of the driving mechanism and plunger relative to one another. The coupling structure may include a rearwardly extending wall to which is joined a radially inwardly extending flange. The coupling structure may be generally C-shaped, with a continuously curved portion having an arc length not exceeding about 180.degree., and optionally may have tangentially extending end segments respectively joined to the continuously curved portions.

Abstract: A multi-pressure injector device, having utility as an angiographic syringe or as an inflation device for balloon angioplasty, wherein an inner barrel/plunger is reposed slidably reposed in an outer barrel, with a second plunger slidably reposed in the inner barrel/plunger, and with the inner barrel/plunger and outer barrel being selectively longitudinally lockable relative to one another along the length of travel of the inner barrel/plunger in the outer barrel. A quick-lock/release structure is disclosed, which is particularly suitable for use with inflation devices for balloon angioplasty. In one aspect, the injector comprises a rotatable connector which is mounted at a distal end of the injector, and includes a distal threaded neck portion and a proximal collar portion of greater diameter than the injector barrel. Such rotatable connector construction facilitates ease of use in attaching the injector to complementary matable structure of catheters, manifolds, and other fluid delivery means.

Abstract: A plunger having a generally converging distal portion, and a proximal face on which is mounted a coupling structure. The coupling structure is transversely engageable by, and transversely disengageable from, a driving mechanism of a power-driven angiographic syringe, and once engaged, cannot be disengaged by rotation of the driving mechanism relative to the plunger in the absence of transverse translational movement of the driving mechanism and plunger relative to one another. The coupling structure may include a pair of laterally spaced-apart retention members, each comprising a leg rearwardly extending from the proximal face of the plunger and joined at a rearward part thereof to a laterally extending bridge segment, to the inner extremity of which is joined a pair of oppositely transversely extending flexible, resilient flange elements.