GB2073591A

GB2073591A - Biopsy instrument

Info

Publication number: GB2073591A
Application number: GB8011889A
Authority: GB
Original assignee: Welsh National School of Medicine
Current assignee: Welsh National School of Medicine
Priority date: 1980-04-10
Filing date: 1980-04-10
Publication date: 1981-10-21

Abstract

A skin biopsy instrument for taking a small skin sample, including a vacuum chamber (11), with a transparent side wall (13) and a thin flat base plate (15) provided with a small aperture (16). A cutting knife (12) lies flat again the bottom plate and is connected to a motor (22) which actuates the knife to cut the sample when suction is applied to cause skin to rise through the opening. <IMAGE>

Description

SPECIFICATION Biopsy instrument This invention relates to an instrument for removing small samples of skin from patients or subjects in vivo. This is a necessary step in the microscopic examination of skin tissue for the investigation and diagnosis of skin disease and the study of the action of drugs on the skin and in general for any close examination of the skin which cannot be performed on the body.

The biopsy may be a troublesome and timeconsuming procedure and often requires local anaesthesia. It is an object of the present invention to provide an instrument and procedure for biopsy which will at least partly overcome some of the present problems.

Broadly stated, the invention consists in an instrument for removing small skin samples in vivo, comprising a chamber with an opening in the lower part, means for connecting the chamber to a source of suction, to cause a bubble of skin to be drawn inwardly through the opening, a cutting element arranged to move across the inner side of the opening to cut a sample from the skin bubble. Preferably the chamber is at least partly transparent so that the skin bubble can be viewed and the chamber also preferably has a thin bottom wall, having a thickness of less than .5 mm.

In any case the instrument preferably includes power means for moving the cutting element. Also according to a preferred feature of the invention the instrument includes means for vibrating.

It is preferred that the chamber and cutting element should be detachable and removable from the remainder of the instrument and they are preferably provided as a disposable sterile pack.

The invention also consists in a method of removing a small skin sample in vivo in which a bubble of skin is raised by suction through an opening in a plate and a cutting element is moved across the opening to cut off the top of the skin bubble.

The invention may be performed in various ways and one specific embodiment, with some possible modification, will now be described with reference to the accompanying drawings, in which: Figure 1 is a somewhat diagrammatic plan view of a skin biopsy instrument according to the invention, Figure 2 is a side elevation, Figures 3, 4 and 5 are plan views of modified forms of cutter, and Figure 6 is a side view of the Figure 5 embodiment.

Referring first to Figures 1 and 2, the instrument comprises a a hand-held case 10 having a disposable chamber 11 attached at its leading end containing a removable cutting knife 12. The chamber 11 has a semi-cylindrical transparent side wall 13, a transparent top wall 14 and a thin flat base plate 15 formed of a metal sheet (e.g., stainless steel) having a thickness of less than .5 mm. and preferably about .2 mm.

This bottom sheet has a small circular aperture 16 near its front edge. The cutting knife 12 has a sharp straight front cutting edge 17 and is designed to lie flat on the upper face of the bottom plate 15. The chamber 11 is provided with an airtight sealing strip around its rear edges and has fastening means e.g., snap fastening heads 18 for connection to the main case 10 of the instrument. The cutting blade 12 likewise has a detachable connection 20 which projects through an aperture in the front wall 21 of the case 10.

Within the case is a small electric motor 22 connected by a lead screw device 23 to the stem 20 such that rotation of the motor causes the stem and hence the blade 12 to move forward across the opening 16.

An electric vibrator 24 within the case is connected via a linkage 25 to the stem 20, to cause lateral vibration of the blade as it is advanced.

The case 10 also has a connection 26 to a remote source of suction which will create a degree of vacuum within the case and hence also within the front chamber 11. This is controlled to be sufficient to raise a bubble of skin through the opening 16 before the biopsy takes place. A control button 27 on the case is connected in circuit with the motor 22 and vibrator 24 which are supplied via an external power lead 28. When depressed the blade 19 is vibrated and simultaneously advances to remove the skin sample and in doing so the blade automatically closes the wound and prevents excessive bleeding under the vacuum conditions. The suction will be disconnected before the instrument is removed from the wound.

In the example of Figure 3 the cutting element is in the form of a small flat circular cutting blade 30 driven by a belt 31 from a spindle 32 connected to a small motor within the casing. In this system the cutting knife is rotated and simultaneously swung in the direction of the area across the opening 16'.

In the construction of Figure 4 the blade 33 is provided with a saw-toothed cutting edge 34 and the design is otherwise similar to that of Figure 1.

In the construction of Figures 5 and 6 the cutting element is a flexible cutting band 35 with a sharp front cutting edge 36 running over two spindles 37, one of which is driven by a small electric motor within the casing.

In all cases the chamber is removable and disposable, and suction is applied within the chamber while the cutting element advances to remove the skin bubble.

Claims

1. An instrument for removing small skin samples in vivo, comprising a chamber with an opening in the lower part, means for connecting the chamber to a source of suction, to cause a bubble or swelling of skin to be drawn inwardly through the opening, and a cutting element arranged to move across the inner side of the opening to cut a sample from the skin bubble or swelling.

2. An instrument according to claim 1, in which the chamber is at least partly transparent so that the skin bubble or swelling can be viewed.

3. An instrument according to claim 1 or claim 2, in which the chamber has a thin bottom wall, having a thickness of less than 0.5 mm.

4. An instrument according to any of the preceding claims, including power means for moving the cutting element.

5. An instrument according to any of the preceding claims including means for vibrating the cutting element.

6. An instrument according to any of the preceding claims, in which the chamber and cutting element are detachable from the remainder of the instrument.

7. An instrumentfortaking a skin sample substantially as described with reference to the accompanying drawings.

8. A method oftaking a skin sample, in which suction is exerted over a small area of the skin to cause a bubble or swelling, the crest of which is shaved off with a sharp cutting instrument.