ULTRASOUND PHANTOM

Abstract

An ultrasound phantom comprising a hydrocarbon gel layer encased in a silicone sleeve, said hydrocarbon gel being doped with inorganic powder.

Claims

1. An ultrasound phantom comprising a hydrocarbon gel layer encased in a silicone sleeve, said hydrocarbon gel being doped with inorganic powder.

2. An ultrasound phantom comprising a hydrocarbon gel layer doped with inorganic powder disposed within an open container, such as a plastic container, said hydrocarbon gel layer having a lower surface in contact with the base of the container and an upper surface, wherein a protective silicone layer covers, such as entirely covers, the upper surface of said hydrocarbon gel layer.

3. An ultrasound phantom as claimed in any preceding claim wherein the hydrocarbon is paraffin or a mineral oil.

4. An ultrasound phantom as claimed in any preceding claim wherein the gelling agent in the hydrocarbon gel layer is a polystyrene/polyolefin copolymer.

5. An ultrasound phantom as claimed in any preceding claim wherein the hydrocarbon gel layer comprises 2 to 10 wt % gelling agent.

6. An ultrasound phantom as claimed in any preceding claim wherein the inorganic powder present in the hydrocarbon gel layer is alumina, titanium dioxide or graphite.

7. An ultrasound phantom as claimed in any preceding claim wherein there is 0.1 to 2.0 wt % inorganic powder present in the hydrocarbon gel layer.

8. An ultrasound phantom as claimed in any preceding claim wherein the silicone sleeve or silicone layer comprises glycerine or a glycol, e.g. 5 to 30 wt % glycerine or a glycol.

9. An ultrasound phantom as claimed in any preceding claim wherein the silicone sleeve or silicone layer comprises inorganic powder, e.g. 0.1 to 2.0 wt % inorganic powder.

10. An ultrasound phantom as claimed in any preceding claim wherein the silicone sleeve or silicone layer comprises pigment to give it the colour of skin.

11. An ultrasound phantom as claimed in any preceding claim wherein one or more tubes pass through the phantom.

12. An ultrasound phantom as claimed in any preceding claim which is cuboidal or shaped like a body part.

13. An ultrasound phantom as claimed in any preceding claim having a thickness of 1.0 to 5.0 cm.

14. An ultrasound phantom as claimed in any preceding claim which is non-aqueous.

15. An ultrasound phantom comprising a hydrocarbon gel layer comprising paraffin or a mineral oil and a polystyrene/polyolefin block copolymer completely encased in a silicone sleeve, said hydrocarbon gel comprising alumina, titanium dioxide or graphite powder and said silicone sleeve comprising an inorganic powder and glycerine.

16. Use of a phantom as claimed in claims 1 to 15 in ultrasonography and/or as a mimic for needle insertion.

17. A process for the preparation of an ultrasound phantom as claimed in claims 1 to 15 comprising preparing a hydrocarbon gel doped with inorganic powder and encasing the same in a silicone sleeve.

Description

BRIEF DESCRIPTION OF THE FIGURES

[0075] FIG. 1 is a cross section of a phantom of the invention. The phantom comprises a silicone rubber sleeve (1) encasing a hydrocarbon gel layer (2). Passing through the phantom are silicone tubes (3) which mimic blood vessels. These tubes are connected to an external liquid source (not shown).

[0076] FIG. 2 is a photograph of a prepared phantom showing the exterior sleeve and tubes passing through the phantom.

[0077] In FIG. 3 the sleeve is cut open to reveal the hydrocarbon gel layer encased within the sleeve. The tubes pass through this hydrocarbon gel layer.

[0078] FIGS. 4, 5 and 6 are ultrasound images. FIG. 4 is an image of a real thigh showing the femoral artery and vein. FIG. 5 is an image using the phantom of the invention (FIG. 5). FIG. 6 is an in-line image (90 degrees out of cross section plane) of a guidewire being inserted into one of the vessels of the phantom.

[0079] FIG. 7 is a depiction of the moulding process. A mould body (1) encases a suspended hydrocarbon gel block (2) with a gap between mould body walls and the gel block to accept the silicone sleeve material. A tube (3) passes through the gel block (2) and mould body (1). The liquid silicone sleeve is poured from vessel (6) into the mould via sprue (4). A clamp (5) compresses the silicone sleeve to the hydrocarbon gel during the curing process.

[0080] FIG. 8 is a partial cross section of a phantom of the invention. The phantom comprises a silicone rubber sleeve layer (1) on top of a hydrocarbon gel layer (2). The hydrocarbon gel layer sits within a housing (7) (bottom not shown). The housing comprises a flange (8) to which the silicone layer adheres. As shown the silicone layer can wrap around the flanges to improve adhesion.

[0081] FIG. 9 is a photograph of a prepared phantom showing the housing and top silicone layer with tubes passing through the phantom.

EXAMPLE

[0082] Pre-mixed paraffin gel (consisting of approximately 95% wt paraffin and 5% wt gelling agent Penreco CP9000) was heated to melting. When molten, approx.1% wt graphite powder was added to the liquid. The liquid was then stirred thoroughly to disperse the powder.

[0083] The liquid paraffin gel mixture was poured into an open mould, encasing two silicone rubber tubes of exterior diameters 7 and 12 mm.

[0084] Once cooled and solidified, the resulting gel block with tubes was removed from the mould and placed in a two-part mould. The two-part mould has space between the gel lock and the insides of the mould, intended to be filled with silicone to form the sleeve.

[0085] The insides of this mould were prepared with a layer of petroleum jelly (Vaseline) to aid in de-moulding and a small amount of talc to give the cast surface a matte finish. This mould was then suspended vertically.

[0086] The two-component silicone (Eco-flex 00-10) was mixed, and a skin-tone pigment was added. This mixture was then degassed in a vacuum chamber (drawing approx. 30 in Hg for ˜5 minutes). The degassed silicone was then poured into the prepared mould and allowed to cure at room temperature for a period of four hours. The mould was opened, and connectors fixed to the tubes.