WO2013045421A1

WO2013045421A1 - Device

Info

Publication number: WO2013045421A1
Application number: PCT/EP2012/068830
Authority: WO
Inventors: Nanno SCHREUDER; Leen VAN DEN HEUVEL; Gerard SWIERS
Original assignee: Ge Healthcare Limited
Priority date: 2011-09-26
Filing date: 2012-09-25
Publication date: 2013-04-04

Abstract

The present invention relates to radiopharmaceuticals and particularly to a device useful in the measurement of radioactivity of a radiopharmaceutical in a syringe. More particularly, the invention provides a device and an adaptor for holding and positioning a syringe containing a pharmaceutical into a dose calibrator for the measurement of the radioactivity of a radiopharmaceutical in the syringe. Further the invention relates to methods of measuring radioactivity using such device or adaptor.

Description

Device

The present invention relates to radiopharmaceuticals and more particularly to a device for holding and positioning a syringe into a dose calibrator for the measurement of radioactivity of a radiopharmaceutical in the syringe. Further the invention relates to methods of measuring radioactivity using such device.

Radiopharmaceuticals are used in the field of nuclear medicine as tracers in the diagnosis and treatment of many diseases. Such radiotracers are used in both SPECT and PET imaging procedures. Many radiopharmaceuticals incorporate a radioactive tracer atom into a larger pharmaceutically-active molecule, which is localized in a body, after which the radionuclide tracer atom allows it to be easily detected with a radioactivity detector, such as a gamma camera or similar gamma imaging device. In such imaging procedures, an individual dose of a premeasured radiotracer is administered to an individual patient. The individual premeasured radiotracer is prepared by a radiotracer supplier. A Cyclotron is most commonly used to prepare the radiotracer. The radiotracer is delivered to a medical facility that administers the individual premeasured radiotracer as a radiopharmaceutical. The individual premeasured radiotracer is prepared by the radiotracer supplier in accordance with a prescription. The prescription includes a prescribed amount of radioactivity at a future time and a date of the prescribed administration in a known volume of a liquid suitable for injection into a living subject.

The conventional process of radiotracer production in a cyclotron performed by a radiotracer supplier is e.g. as follows: The radiotracer supplier irradiates a target material in the cyclotron with a beam of protons or deuterons to produce a desired amount of radioactivity in the target material. The extent of irradiation is planned to fulfill the need of radioactivity at the prescribed future time and date. The irradiated target material is a radioisotope. Examples of cyclotron produced radioisotopes include nitrogen-13, fluorine-18, carbon-1 1 and oxygen-15. Often, compounds are bond to the radioisotope to produce radiotracers such as

fluorodeoxyglucose (FDG) which is produced using fluorine-18. Other radiotracers include nitrogen-13 ammonia which is used in myocardial applications, carbon-1 1 tracers which are commonly used in neurologic applications; and oxygen-15 gas as well as tracers derived from it which are commonly used in blood flow applications. ¹⁸F-FDG is by far the most commonly used radiotracer and has a half life of 109 minutes allowing for its distribution from a centralized radiopharmacy to multiple imaging sites. Typically the radiotracer supplier packages the radiotracer as individual doses, and will prepare a number of individual doses for each medical facility each day. Typically, the radiopharmaceuticals are reconstituted and then dispensed in syringes. A typical radiopharmacy might dispense as many as 200-800 syringes a day. Syringes of different sizes, such as 1 ml, 3 ml, 5 ml and 10 ml are used. Each syringe has to be controlled and the radioactivity is measured for each individual syringe. For such measurement of the radioactivity a dose calibrator is used. The dose calibrator comprises a console and a well chamber. The syringe is lowered into the well chamber wherein the measurement takes place.

In the procedures used to measure the radioactivity, there is a risk that the operator is exposed to radioactivity, particularly at the extremities, the hands and fingers of the operator, as the operator manipulates the syringe. The close proximity to the radioactivity may result in numerous instances of low levels of exposure to radioactivity that can be harmful to the health of the operator. In an existing method for measurement of the radioactivity of the pharmaceutical in a syringe a so called well-dipper is used. The main component of the well- dipper is a flat circular disc with a hole in the middle. The syringe body is inserted into the hole of the disc, such that the flanges of the syringe rest on the disc. When the syringe is placed in the hole of the well-dipper this may be lowered into the well chamber of the dose calibrator such that the syringe is essentially vertically positioned in the well chamber, with the syringe tip pointing downwards. The method is time consuming as the well-dipper needs to be lifted out and lowered into the well chamber. Further, often adjustments are needed to ensure the syringe is positioned correctly. The time required to properly align and position a syringe within the well-dipper results in prolonged exposure of the operator's extremities to the activity within the syringe.

For the reasons stated above, and for other reasons stated below, there is a need in the art for an improved device for holding and positioning a syringe into a dose calibrator for measurement of the radioactivity of a pharmaceutical in a syringe. In addition, there is a need to reduce the exposure of people, such as operators, to radioactivity during the manual steps of measuring the radioactivity of a radiopharmaceutical in a syringe.

Figure 1 depicts a syringe dipping device of the prior art.

Figure 2 depicts a device of the present invention.

Figure 3 depicts a syringe holder of the device of Figure 2, and a syringe inserted through the holder cavity thereof. Figure 4 depicts an adaptor of the present invention, assembled to the dipper of Figure 1 , and depicts a syringe inserted through the syringe cavity thereof.

The applicant has now surprisingly identified an improved device for holding and positioning a syringe into a dose calibrator for measurement of the radioactivity of a pharmaceutical in the syringe. With the new device the measurement procedure is faster and requires less activity by the operator and also reduces operator exposure to the radioactive dose.

Thus, in a first aspect the invention provides a device comprising

i) a cross piece handle;

ii) a holder for a syringe comprising a holder body defining a first aperture and a second aperture, the body comprising an inwardly-facing frustroconical surface defining a holder cavity extending in fluid communication between the first and second apertures; iii) an elongate spacer bar extending between the cross piece handle and the holder.

The device is adapted to hold and position a syringe into the well chamber of the dose calibrator such that the syringe is essentially vertically positioned in the well chamber, with the syringe tip pointing downwards. When positioned in the well chamber the radioactivity may be measured. The well chamber of the dose calibrator comprises a perimetrical rim defining the opening to a well chamber cavity.

The inwardly facing frustroconical surface of the holder body is desirably a right circular cone with its apex cut off by a plane parallel to the cone's base, although shaped tapers to the surface are contemplated by the present invention. The first and second apertures are defined by the base plane and the truncation plane of the cone. The cone's base defines the wide upper first aperture and the second aperture is the narrow lower opening. The holder body defines the opposed first and second apertures. The holder is adapted to be fitted with a syringe, such that the syringe, with the syringe tip pointing downwards, will extend through the holder body so that the syringe flanges make contact with the frustroconical wall. The shape of the frustroconcial wall will direct the syringe tip towards the narrow second aperture so that a significant portion of the syringe barrel will pass through the holder cavity and extend beyond the holder. The second aperture at the bottom of the holder is too narrow for the syringe flanges to pass through, thus the holder holds the syringe steadily. In one embodiment the holder body includes an outwardly facing cylindrical wall. Hence, seen from the outside the holder body is essentially a cylinder. The dimension of the diameter of the cylinder is adapted to fit into the well chamber. Accordingly, the diameter of the outwardly facing cylindrical wall is smaller, preferably only slightly smaller, than the diameter of the perimetrical rim defining the opening to the well chamber cavity.

The holder body may further include a spacer bar aperture into which the spacer bar attaches to the holder. In one embodiment the spacer bar aperture of the holder is located in the periphery thereof. In the embodiment wherein the holder body includes an outwardly facing cylindrical wall, the spacer bar aperture preferably comprises an opening, such as a slit, in the cylindrical wall wherein the spacer bar fits. In one embodiment the spacer bar aperture has a semi-circular cross section.

The holder body, and the adaptor described below, may be made of different materials and is preferably made of a synthetic polymer. In one embodiment the holder body is made of a transparent thermoplastic. A preferred material is poly(methyl methacrylate) (PMMA), sold under many different names including Lucite and Perspex. In one embodiment the holder body is made of a soft material, such as a soft synthetic polymer. This enables the operator to drop the syringe into the holder with less risk of damage to the syringe.

The crosspiece handle is transversely oriented with respect to the spacer bar. The handle is in one embodiment an elongate rod, preferably with the halfway point defining the connection point with the spacer bar. To position the device in the well chamber, and to remove a syringe from the holder of the device, the operator will use one hand holding the crosspiece handle. The longer the handle, the greater the offset from the spacer bar and this minimizes the risk of exposure to the operator. The crosspiece handle is of a dimension, i.e. length, at least greater than that of the well chamber opening, i.e. greater than the diameter of the perimetrical rim defining the opening to the well chamber cavity.

The elongate spacer bar connects the holder and the crosspiece handle extending between these. When placing a syringe in the holder body the spacer bar and the syringe are positioned essentially in parallel. The spacer bar desirably attaches to the holder adjacent the periphery thereof. The spacer bar is preferably adapted to fit with the spacer bar aperture of the holder.

The device may further comprise a planar circular disc with a hole in the middle for positioning right below the holder. Hence, the planar circular disc has a centrally-located passageway there through. The flat circular disc defines a centrally-located passageway therethrough for positioning in underlying registry with the holder cavity. The prior art well- dipper comprises such planar circular disc. In this embodiment the holder of the device of the present invention is adapted to be placed on top of the circular disc such that the second aperture of the holder aligns in overlying registry with the passageway of the circular disc. When placing the syringe in the holder a significant portion of the syringe barrel will pass through the holder cavity and extend beyond the holder and through the centrally-located passageway of the circular disc. The circular disc preferably has about the same dimensions, i.e. diameter as the diameter of the outwardly facing cylindrical wall of the holder. Further, the diameter of the passageway in the disc is desirably about the same as the diameter of the second aperture of the holder, desirably even larger. Hence in a further aspect, the present invention provides an adaptor for a well-dipping device, wherein the dipping device comprises an elongate transversely-oriented handle, a syringe holder comprising a circular disc defining a syringe passageway therethrough, and an elongate spacer bar extending between said syringe holder and said handle,

said adaptor comprising:

an adaptor body defining opposed first and second apertures and including an inwardly- facing frustroconical surface defining a holder cavity extending in fluid communication between said first and second apertures.

The adaptor for the well-dipper device is for use with a dose-activity detector, i.e. a dose calibrator, wherein the dose activity detector includes a chamber well for receiving the dipping device. The adaptor is adapted to fit with the well-dipper such that it can be placed on top of the circular disc of this.

The adaptor desirably includes a transverse planar surface defining said second aperture, such that the planar surface engages the circular disc of the dipper device, when the adaptor is placed on the well-dipper. The adaptor is adapted to fit with the well-dipper such that it can be placed on top of the circular disc, such that the second aperture of the adaptor body aligns in overlying registry with the passageway of the circular planar disc. Additionally, the adaptor desirably includes an outwardly-facing perimetrical wall defining an aperture therein for receiving a portion of the spacer bar of the dipping device. In one embodiment, the adaptor includes the same features as the holder of the device of the first aspect.

As the portion of the syringe barrel containing the radioactive sample is typically contained proximate to the dispense end of the syringe, the vertical displacement of the syringe by the frustroconical surface of the adaptor does not prevent accurate measurement of the sample activity within the well of the detector, as compared to using the prior art dipper alone. In one embodiment the holder for the syringe, e.g. the adaptor, is connected in overlying registry to a circular disc, such as to the circular disc of the dipper, with screws. The screws can be made of any acceptable material as metals, such as stainless steel, or plastics, and are preferably made of plastics. Plastic screws are preferred due to their resistance to cleaning agents, and as they save some weight. The circular disc may further comprise a spacer bar aperture into which the spacer bar attaches to the disc.

The term "essentially vertical" as used herein denotes that the longitudinal axis of the syringe should be positioned within about 30° of vertical, preferably within 15° and more preferably within 5° of vertical.

In a third aspect, the invention provides a method for measuring radioactivity of a

radiopharmaceutical in a syringe, the method comprising using the device of the first aspect or the adaptor of the second aspect.

The method preferably includes the steps of

i) positioning the holder of the device in a well chamber;

ii) placing a syringe comprising a pharmaceutical in the holder of the device;

iii) measuring the radioactivity of the pharmaceutical in the syringe.

With the new device the measurement operation is simplified. The measurement is faster and requires fewer operation steps by the operator, also reducing the time spent handling the radioactive source and hence reducing the operator's exposure to radioactivity. Using the device and method of the invention the reduction of time spent on the measurement of the radioactivity of syringes is about 30 % compared to using the existing devices and methods.

With the dipper of the prior art, the well-dipper, would have to be retracted from the well chamber in order to load the syringe into the hole of the circular disc, before the well-dipper with the syringe in it is lowered into the chamber. The operator would use both hands for this operation, and both hands could be exposed to radioactivity. Further, the operator would have to make sure the syringe is positioned correctly in the well chamber. With the new device and method of the invention, the holder of the device is lowered into the well chamber of the dose calibrator before placing the syringe into the holder. After having positioned the holder of the device in the chamber, the syringe is loaded into it. The frustroconical surface of the holder cavity will direct the syringe through the holder cavity and through the second aperture of the holder until the flanges reach the surface of the cone. The holder will hold the syringe by the flanges. The loading of the syringe into the holder, already positioned in the well chamber, can be performed with one hand, preferably using a pair of tongs, and hence the operator exposure to radiation is reduced. Further, the holder, with its conical inner surface aligns the syringe into the correct position, and no operation steps by the operator are needed to ensure correct positioning. When the syringe is placed in the holder in the well chamber the radioactivity of the syringe content can be measured. To remove the syringe after the measurement is made, the operator would use one hand to lift the cross piece handle until able to grasp the syringe with the tongs.

In a further aspect, the invention provides the use of the device of the first aspect or the adaptor of the second aspect in a method of measuring radioactivity of a syringe comprising a radiopharmaceutical. The aspect includes the same features and steps as the first aspects.

Preferred embodiments of the invention will now be described by way of example only and with reference to the accompanying drawings, in which

Figure 1 shows the well-dipper 1 of the state of the art comprising a flat circular disc 2 with a hole 3 in the centre for insertion of a syringe. The disc 2 may further comprise a spacer bar aperture 4 into which a spacer bar 5 attaches to the disc 2. The spacer bar 5 may be connected to a cross piece handle 6.

Figure 2 shows a device 10 of the invention comprising a cross piece handle 1 1 ,

a holder 12 for a syringe comprising a holder body 13 defining a first aperture 14 and a second aperture 15, the body comprising an inwardly-facing frustroconical surface 16 defining a holder cavity 17 extending in fluid communication between the first and second apertures 14, 15. The device further comprises an elongate spacer bar 18 extending between the cross piece handle 1 1 and the holder 12. In this one embodiment the holder body 13 includes an outwardly facing cylindrical wall 19 which defines a longitudinally- oriented spacer bar aperture 21 thereon into which the spacer bar 18 is inserted and attaches to the holder.

In Figure 3 a syringe 30 is inserted into a holder 12 of the device 10 of the invention. In this embodiment the device 10 may also be called an adaptor 40, as shown in figure 4, to be used together with a dipper. The frustroconical surface 16 of the holder cavity 17 will direct the syringe 30 through the holder cavity 17 and through the second aperture 15 of the holder 12 until the oppositely-extending flanges 31 of the syringe reach the surface 16 of the cone. In Figure 4, an adaptor 40 of the present invention is shown fitted to a dipper of the prior art. Adaptor 40 provides the holder 42 for a syringe and includes a holder body 43 defining opposed first and second transverse apertures 44 and 45, respectively. Body 43 includes an inwardly-facing frustroconical surface 46 defining a holder cavity 47 extending in fluid communication between first and second apertures 44 and 45. Adaptor 40 includes outwardly-facing cylindrical wall 49. Cylindrical wall 49 desirably defines outwardly-opening spacer aperture 51 which receives a portion of a spacer bar 5 of the dipper. Adaptor 40 includes a transversely-oriented planar lower surface 52 which rests upon disc 2 of the dipper. Second aperture 45 of adaptor 40 is sized to be positioned in overlying registry with passageway 3 of disc 2. Second aperture 45 has a span that is desirably coextensive with passageway 3 and desirably no larger. Flanges 31 of syringe 30 are shown to engage adaptor 40 as described hereinabove.

Examples:

Example 1. Comparison study, comparing a state of the art holder (well-dipper) with a device of the invention (speed-dipper).

A study was performed to compare a device of the invention (speed-dipper) with the state of the art device (well-dipper) comprising a handle, a space bar and a circular disc with a hole in the middle. The radioactivity of a radiopharmaceutical filled in syringes of 1 ml and 3 ml was measured using the two types of devices. Each measurement involved placing and removing syringes in a well chamber 20 times. The time taken to complete the sequence of 20 measurements was recorded. For each syringe for both devices, the measurement sequence was repeated 20 times for statistical purposes.

The results are provided in table 1 below. Table 1 : Time to measure 20 syringes

Using the device and method of the invention was significantly faster for the 1 ml and 3 ml syringes than using the state of the art device.

Claims

Claims:

A device comprising

i) a cross piece handle;

A device as claimed in claim 1 wherein the holder is adapted to engage a syringe, such that the syringe will extend through the holder so that the syringe flanges make contact with the frustroconical surface.

A device as claimed in claim 1 or 2 wherein the holder body further includes an outwardly facing cylindrical wall.

A device as claimed in either of claims 1 to 3 wherein the holder body further defines a spacer bar aperture into which the spacer bar attaches to the holder.

A device as claimed in claim 3 or 4 wherein the cylindrical wall of the holder body defines a radially-outward opening in fluid communication with said spacer bar aperture.

A device as claimed in any of the claims 1 to 5 wherein the holder is made of a synthetic polymer.

7. A device as claimed in any of the claims 1 to 6 further comprising a flat circular disc defining a centrally-located passageway therethrough for positioning in underlying registry with the holder cavity.

A method for measuring radioactivity of a radiopharmaceutical in a syringe, the method comprising using the device of claims 1 to 7.

9. An adaptor for a well-dipping device, the dipping device comprising an elongate

transversely-oriented handle, a syringe holder comprising a circular disc defining a syringe passageway therethrough, and an elongate spacer bar extending between said syringe holder and said handle, said adaptor comprising: an adaptor body defining opposed first and second apertures and including an inwardly-facing frustroconical surface defining a holder cavity extending in fluid communication between said first and second apertures.

An adaptor of claim 9, wherein said adaptor body further comprises a transverse planar surface defining said second aperture, such that the planar surface engages the circular disc of the dipper device.

An adaptor of claim 9, further comprising an outwardly-facing perimetrical wall defining an aperture therein for receiving a portion of the spacer bar of the dipping device.