Angiographic syringe for use with an angiographic injector

BACKGROUND OF THE INVENTION

Field of the Invention

This invention relates to the field of angiography. Angiography is the study of blood vessels with the use of x-rays while injecting an iodine-based or other fluid (contrast media) into the body through a catheter situated in a blood vessel. An angiographic injector utilizes an angiographic syringe filled with contrast media and serves to control the delivery rate, amount, pressure, etc., of the fluid being injected.

Background of the Prior Art

Although there are many angiographic injectors (see US-A-4,006,736 being the nearest state of the art, for example) and many angiographic syringes commercially available in the world market, there are certain areas where improvements or advances can be made. For example, there is no known multiple-syringe angiographic injector permitting the syringe plunger to be disengaged without retracting the plunger back through the syringe and hence possibly drawing blood and other fluid from the patient. Also, the design of the prior art syringe may not maximize the purging of air from within because of the taper angle of the syringe's end. Finally, the length of the discharge extension in prior art syringes does not permit efficient handling of the syringe by the surgeon.

The object of the invention is to provide an angiographic syringe fixedly mountable within the mounting means of an angiographic injector to maintain alignment between the syringe and the mounting means and an angiographic injector and syringe assembly.

Yet another object of this invention is to provide an angiographic syringe which promotes improved air removal therefrom.

Still another object of this invention is to provide an angiographic syringe which increases the size of the sterile work field.

SUMMARY OF THE INVENTION

In general, an angiographic syringe includes a plunger which is advanceable through a tubular body for forcing contrast media from a discharge end of the tubular body into the vascular system of an animal in an injection operation. The plunger is advanced through the tubular body by an actuating mechanism of an angiographic injector. After the injection operation has been completed, the actuating mechanism is retractable relative to the plunger of the syringe without causing any substantial retraction of the plunger in the tubular body so as to draw body fluid of the animal into the syringe.

More specifically, the foregoing and other objects of the invention are achieved by providing a novel angiographic injector utilizing a specially adapted novel angiographic syringe. The angiographic injector has an injector portion which includes a rotating turret for housing multiple syringes in readiness for injection. The injector further employs a driving mechanism for connecting with and controlling the movement of the syringe plunger once the syringe is in place for injection. Through the use of guide means on the syringe and corresponding alignment means on the pressure jacket, and syringe is alignably and securely mounted within the pressure jacket on the rotating turret. In certain arrangements, the syringe plunger is positioned within the syringe such that when the syringe is mounted within the pressure jacket, a plunger connecting means will be properly aligned for mating with the driving mechanism. This mating occurs upon rotation of the turret into position for injection on the injector portion. Once the injection is complete, the driving mechanism may be disengaged from the plunger connecting means by rotating the driving mechanism or the syringe plunger, thereby freeing the driving mechanism from the plunger so the driving mechanism can be retracted from the syringe. In other arrangements, prealignment of the plunger and the drive mechanism, and/or rotation of either the syringe plunger or the drive mechanism to release the driving mechanism from the plunger are not necessary. A discharge extension of the angiographic syringe also has been lengthened and an intermediate portion of the syringe has been given a less severe taper.

BRIEF DESCRIPTION OF THE DRAWINGS

<ul id="ul0001" list-style="none" compact="compact"><li>Figure 1 is a perspective view of an angiographic injector of the present invention, illustrating an injector portion and turret assembly;</li><li>Figure 2 is a cross-sectional view of a syringe of the present invention;</li><li>Figure 3 is a sectional plan view of a tapered neck portion of the syringe of Figure 2;</li><li>Figure 4 is a transverse cross-sectional view taken along line 4-4 of Figure 2;</li><li>Figure 5 is a side view of a pressure jacket and syringe assembly of the present invention;</li><li>Figure 6 is a front view of the pressure jacket of Figure 5;</li><li>Figure 7 is a view of the injector of Figure 1 wherein the turret is rotated out of operative position to expose the plunger-engaging driving mechanism of the injector portion;</li><li>Figure 8 is an end view of the syringe of Figure 2;</li><li>Figure 9 is a side view of the syringe and driving mechanism as mated and prepared for injection;</li><li>Figure 10 is a view similar to that of Figure 9, showing the syringe and driving mechanism in a plunger-release position as a result of rotation of the driving mechanism;</li></ul>

DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring now to Figures 1 and 2, the angiographic injector of the present invention is shown generally at 10. The injector 10 comprises an injector portion 12 and a control unit (not shown), injector portion 12 further comprising a turret 14 rotatably mounted about a shaft 61. Shaft 61 includes an aperture (not shown) which aligns with aperture 62a in turret 14 when turret 14 is in position for injection. Pin 62 passes through the apertures, thereby holding turret 14 in its proper position. Two pressure jackets (mounting means) 16 and 16a are fixed in turret 14 and house respective syringe cartridges 18 and 18a.

The syringe 18 comprises an elongated tubular body 22 and a coaxial discharge extension 20, connected by an intermediate portion 24. The tubular body 22 has a circular, outwardly extending flange 32 on one end, as well as a plunger 38-1 slideably positioned within the tubular body 22. Flange 32 serves as an abutment face for associating with the rear portion of pressure jacket 16. Plunger 38-1 comprises a base member 38a, and two hook members 38b extending therefrom; the plunger 38-1 serving to control the ejection of fluid contained within syringe 18 in a desired quantity and at a desired rate. Hook members 38b are designed to facilitate axial movement of plunger 38-1.

Intermediate portion 24 of syringe 18 is in the shape of a funnel and comprises two sections, a hollow cone 24a and a tapered neck 24b. On the surface of the tapered neck 24b are located one or more guide extensions, three being illustrated at 26, 28 and 30. Extending axially from the tapered neck 24b is discharge extension 20 which includes a nozzle 20a, and terminates in discharge outlet 36. Discharge extension 20 serves as a guide means and provides an attachment point for connector 42 which engages with a catheter (not shown). The configuration of the nozzle 20a of discharge extension 20 corresponds with generally accepted taper lengths and angles as described in ASA Standard Z-1955 so as to be mateable with conventional catheters. Inner passageway 34 within extension 20 can be generally cylindrical, and provides communication between discharge outlet 36 and the interior of tubular body 22.

In an effort to improve the air removal capability of syringe 18, hollow cone 24a has a taper angle ranging between 40° and 50°, as compared to the 30° angle of conventional prior art syringes. In the illustrated embodiment, cone 24a has a 45° taper angle so as to compromise between maximum air removal and manufacturing ease. Similarly, plunger 38-1 has a taper angle corresponding to that of hollow cone 24a. In addition, the combined length of tapered neck 24b and discharge extension 20 ranges between 7,3 cm (2 7/8 inches) and 8,9 cm (3 1/2 inches), thereby providing the physician with a larger sterile work field. In the preferred embodiment, this combined length is set at 8,3 cm (3 1/4 inches) so as to compromise between maximum strength and length of tapered neck 24b and discharge extension 20, and manufacturing ease.

Figures 3 and 4 illustrate more clearly the features and disposition of guide extensions 26, 28 and 30. In essence, guide extensions 26, 28 and 30 are raised portions of syringe 18 which extend from the end of hollow cone 24a to approximately the middle of tapered neck 24b. Although preferably made of the same material as syringe 18 and integrally formed therewith, guide extensions 26, 28 and 30 may be made of other types of plastic or suitable materials, syringe 18 preferably being formed from a relatively rigid, translucent plastic material. While the preferred embodiment employs three guide extensions 26, 28 and 30, more or less may be used. Also, the extensions may be identical, or they may be of different dimensions. For example, as shown, side guide extension 28 is larger in width but smaller in height than either top guide extension 26 or bottom guide extension 30. It also should be noted that located on the flange 32 of tubular body 22 is an alignment edge 40 which is in line with guide extension 28.

Alignment edge 40 is used to facilitate assemblage of syringe 18 with pressure jacket 16, as shown in Figures 5 and 6. Typically, syringe 18 is used together with pressure jacket 16 as a single, functional unit used in conjunction with an angiographic injector. In particular, pressure jackets 16 and 16a are securely and alignably mounted within the turret 14 so as to provide a means for mounting syringes 18 and 18a on turret 14 for injection. Pressure jacket 16 has a hollow body portion 51, which is substantially the same length as tubular body 22 of syringe 18, and a conical nose section 52, which is designed to fit over the hollow cone section 24a of syringe 18. At the end of conical nose section 52 is end face 54 which has guide extension notches 46, 48 and 50 formed therein. Guide extension notches 46, 48 and 50 correspond to and are substantially of the same dimensions as guide extensions 26, 28 and 30, respectively. While the preferred embodiment employs three guide extension notches 46, 48 and 50, more or less may be used.

Located on the opposite end of pressure jacket 16 is an alignment indicator 44 which corresponds to alignment edge 40 of syringe 18. Alignment indicator 44 is used to ensure proper alignment of guide extensions 26, 28 and 30 with guide extension notches 46, 48 and 50 as syringe 18 is placed into pressure jacket 16. Once within pressure jacket 16, the tubular body 22 and hollow cone 24a portions of syringe 18 are completely enveloped by pressure jacket 16, while tapered neck 24b and discharge extension 20 protrude through the end face opening 56 so as to facilitate connection with a catheter. Being arranged in this manner, guide extensions 26, 28 and 30 prevent syringe 18 from rotating within pressure jacket 16 and serve to align syringe 18 with both pressure jacket 16 and turret 14.

Referring now to Figures 1 and 7, the two-syringe turret mechanism will be described in further detail. Turret 14, which houses pressure jackets 16 and 16a and syringes 18 and 18a is equipped with two projecting stops 58a and 58b. Fixed to the injector portion 12 are abutment members 60a and 60b adapted to associate with the stops 58a and 58b, respectively. The association between the stops 58a and 58b and the abutment members 60a and 60b limits the rotation of turret 14 from the position illustrated in Figure 1 to the position which would be achieved by rotating turret 14 in the direction of arrow T. Therefore, once syringe 18a is in position for injection as shown in Figure 1, turret 14 can only turn in the direction of arrow T until stop 58a associates with abutment member 60a, thereby ending rotational movement of turret 14 and aligning syringe 18 for injection.

Figure 7 illustrates the position of turret 14 achievable upon partial rotation in the direction of arrow T from the position shown in Figure 1. In this intermediate position, a driving mechanism, shown generally at 66-1 in its fully retracted position, is exposed. Driving mechanism 66-1 includes a base portion 68, a stem 69 and a rectangular head 70 extending from the base portion 68 and integrally formed therewith. In this embodiment, as seen best in Figure 9, plunger hook members 38b are L-shaped and are disposed so as to define an aperture 39 therebetween and an access slot 39a communicating with the aperture 39. This aperture 39 and access slot 39a are designed to mate with the head 70 and stem 69 of driving mechanism 66-1, such that head 70 fits within the aperture 39 and stem 69 extends through the access slot 39a. Ram elements 64a and 64b are integral with and extend from the main surface of the driving mechanism. This piston and ram arrangement is motor driven by a mechanism mounted in injector head 12, and has the same physical and operational characteristics as its counterpart disclosed in US-A-4,006,736. Therefore, its configuration and operation will not be discussed in detail.

In operation, and referring now to Figures 1 and 7-10, syringes 18 and 18a are secured in pressure jackets 16 and 16a, respectively, by aligning syringe alignment edge 40 with pressure jacket alignment indicator 44 upon insertion of syringes 18 and 18a. By effecting such alignment, guide extensions 26, 28 and 30 pass through notches 46, 48 and 50, respectively, thereby holding syringes 18 and 18a in alignment within pressure jackets 16 and 16a.

The proper alignment of syringes 18 and 18a and pressure jackets 16 and 16a is of critical importance because of the operational characteristics of the driving mechanism 66-1. Specifically, syringe plunger hook members 38b must be in proper position to mate with the head 70 of driving mechanism 66-1.

Figure 8 is a rear view of the syringe 18 illustrating the proper alignment of the plunger 38-1 therein. During manufacture of syringe 18, plunger 38-1 is disposed within syringe 18 such that hook members 38b extend in a predetermined relationship with the alignment edge 40 and hence with guide extensions 26, 28 and 30. As illustrated, hook members 38b extend inwardly toward the center of plunger 38-1 and are perpendicular to alignment edge 40. Therefore, pressure jacket 16 must be mounted to turret 14 to as to permit alignment of head 70 and hook members 38b. In the illustrated embodiment, this alignment is achieved by mounting pressure jacket 16 on turret 14 such that alignment indicator 44 is in a vertical disposition when turret 14 is in the position shown in Figure 1.

Once the pressure jackets 16 and 16a are in place on turret 14, and syringes 18 and 18a secured therein, turret 14 is rotated in the direction of arrow T, as shown in Figure 7, until projecting stop 58a engages corresponding abutment member 60a. Plunger 38-1 is disposed at the end of syringe 18 with hook members 38b protruding therefrom such that hook members 38b mate or releasably interlock with head 70 and the driving mechanism 66-1 upon rotation of the turret 14, such that the hook members and the head form respective parts of a releasable driving connection between the plunger and the driving mechanism. In particular, head 70 fits into the aperture 39 formed by hook members 38b, with stem 69 extending out from the aperture 39 through access slot 39a. Figure 9 illustrates the configuration of driving mechanism 66-1 and plunger 38-1 upon mating, focusing only on the connection between the two. As this figure illustrates, the dimensions of hook members 38b, as well as head 70 and stem 69 are critical to a proper fit. Once in the position illustrated in Figure 9, injection may proceed through the actuation of driving mechanism 66-1, as discussed in US-A-4,006,736. In particular, driving mechanism 66-1 may be moved forward, thus driving plunger 38-1 through syringe 18 and expelling air therefrom. After syringe 18 is connected to a source of contrast media, driving mechanism 66-1 may be retracted from syringe 18, thus pulling plunger 38-1 back through syringe 18 so as to draw contrast media into syringe 18. Once filled, syringe 18 is ready for injection.

After the injection has been carried out, driving mechanism 66-1 may be disengaged from plunger 38 as shown in Figures 9 and 10. Without reversing its movement, driving mechanism 66-1, shown in Figure 9, is rotated 90° in the direction of arrow R. This rotational movement results in the configuration shown in Figure 10, wherein head 70 extends from aperture 39 on either side. As shown in Figure 10, the depth d of head 70 must be smaller than the width of the access slot 39a so as to allow removal therefrom. Disengagement is then effected by retracting driving mechanism 66-1 in the direction of arrow D so that head 70 passes through access slot 39a. Because no reverse pressure is applied to plunger 38-1, the risks attendant to drawing the plunger 38-1 back through the syringe 18 are eliminated.

Although particular embodiments of the present invention have been illustrated and described, it will be apparent to those skilled in the art that various changes and modifications can be made without departing from the scope of the present claims. For example, the relative positions of the parts of the plunder release mechanisms on the plungers 38 and the drive mechanisms 66, such as the hook members 38b on the plunger 38-1, and the stem 69 and head 70 of the driving mechanism 66-1, in Figures 1-10, can be reversed, with the stem and head mounted on the plunger and the hook members mounted on the drive mechanism. It therefore is the intent to encompass within the appended claims all such changes and modifications that fall within the scope of the present invention.