GB2396562A

GB2396562A - Cover for a medical probe

Info

Publication number: GB2396562A
Application number: GB0330086A
Authority: GB
Inventors: Nicholas James Tyrrell
Original assignee: Rocket Medical PLC
Current assignee: Rocket Medical PLC
Priority date: 2002-12-28
Filing date: 2003-12-29
Publication date: 2004-06-30
Also published as: GB0330086D0

Abstract

A disposable cover 20 for a heated medical probe (10 fig 6) comprising a sheath of protective material with a first open end 22, a second closed end 24 and a body portion 26. The cover finds particular application when used in conjunction with vaginal probes for use in thermal coagulation therapy of the cervix. The sheath is ideally composed of a flexible silicone rubber which can resist the heat generated by such probes while still allowing the heat transfer necessary to enable effective treatment. The end 24 may be profiled to minimise an air gap around the tip of the probe. The open end 22 may have a resilient retaining ring 22a for securing the cover to the probe. The cover may include a lubricant and a disinfecting agent.

Description

1 "Probe Cover" 3 This invention relates to disposable protective 4

sheaths for medical apparatus, particularly but not 5 exclusively, sheaths for heated probes used in the 6 treatment of precervical cancer and benign lesions.

8 It is known to use a heated probe for the treatment 9 of precervical cancer and benign cervical lesions.

10 The heated probe is usually inserted into the 11 patient's vagina and the heated tip is applied to 12 diseased areas of the cervix, thereby coagulating 13 the epithelium. Over time, healthy tissue replaces 14 the areas of the epithelium that have been 15 coagulated.

17 Formerly, many of the devices featured a self 18 sterilization process, whereby the probe was heated 19 to around 140 C for around three minutes. In 20 practice this was deemed to be "high level 21 disinfection" and was thought to be perfectly 22 appropriate for treatment of the probe.

2 However, this has been deemed to be insufficient, 3 particularly in the wake of new variant CAD, and 4 many of the probes that are now supplied are able to 5 withstand sterilization by autoclave.

7 Many existing probes cannot withstand sterilization 8 by autoclave, but the cost of purchasing new probes 9 can be unattractive.

11 According to the present invention there is provided 12 a disposable cover for a heated medical probe, 13 comprising a sheath of protective material with a 14 first open end, a second closed end and a body 15 portion.

17 Preferably the second closed end is profiled to 18 minimise the air gap between the tip of the heated 19 medical probe and the closed end.

21 Preferably, the material is capable of withstanding 22 a temperature greater than 100 C; more preferably 23 130-150 C for at least 3 minutes.

25 Preferably, the cover is shaped and dimensioned for 26 fitting over a vaginal probe for use in thermal 27 coagulation therapy of the cervix.

29 Preferably the material is flexible, more preferably 30 has good heat conductance, and most preferably is a 31 silicone rubber.

t 1 Preferably the cover is substantially circular in 2 cross section.

4 Preferably the first open end has a resilient 5 retaining ring for securing it to a probe.

7 An embodiment of the invention will now be 8 described, by way of example only, with reference to 9 the following drawings in which: 11 Fig. 1 is an elevation view of a heated medical 12 probe; 14 Fig. 2 is an elevation view of a sheath 15 according to the present invention; 17 Fig. 3 is an elevation view of a first open end 18 of the sheath of Fig. 2; 2 0 Fig. 4 is an elevation view of a second closed 2 1 end of the sheath of Fig. 2; 23 Fig. 5 is an elevation view of an alternative 24 second closed end of a sheath according to the 2 5 present invention; 27 Fig. 6 is an elevation view of the sheath in 2 8 situ on the probe; and 3 0 Fig. 7 is an elevation of a second embodiment 31 of a sheath according to the present invention, 32 also in situ on a probe.

2 Referring initially to Fig. 1 there is shown a 3 heated medical probe, generally referred to as 10.

4 For clarity the power source/control unit and power 5 transmission wire have been omitted.

7 The heated medical probe 10 comprises a handle 12, a 8 stem 14 and a heated tip 16. The power transmission 9 wire (not shown) inserts into the base 12a of the 10 handle 12. The operator holds the probe 10 by the 11 handle 12 and the heated tip 16 is applied to the 12 area of the cervix to be treated.

14 In Fig. 2 a sheath according to the present 15 invention is shown, generally referred to as 20.

16 The sheath 20 comprises a first open end 22, a 17 second closed end 24 and a body portion 26. Around 18 the first open end 22 is a resilient retaining ring 19 22a.

21 The sheath 20 is formed in three separate sections 22 which are then joined together. The three separate 23 sections are the tubular body portion 26; an end cap 24 28 which forms the second closed end 24; and finally 25 a ring section 30 which forms the first open end 22 26 and the resilient retaining ring 22a. Details of 27 the end cap 28 and ring section 30 are shown in 28 Figs. 3 and 4.

30 The section are formed by injection moulding of 31 liquid silicone rubber, but it will be understood by

1 those skilled in the art that other suitable 2 manufacturing processes may be used.

4 The tubular body portion 26 is approximately 150mm 5 long, with an internal diameter of 12mm. The 6 overall thickness of the rubber is 0.5mm. The end 7 cap 28 has an approximate overall length of 16.5mm, 8 with the hemispherical end portion 28a having a 9 radius of approximately 6.5mm. The socket portion 10 28b of the end cap 28 has an internal diameter of 11 approximately 13mm, sufficient to receive the 12 tubular body portion 26 as shown in Fig. 4. The 13 overall thickness of the rubber of the end cap 28 is 14 approximately 0.5mm. The ring section 30 likewise 15 has a socket portion 3Oa having an internal diameter 16 of approximately 13mm, again sufficient to receive 17 the tubular body portion 26, and a rubber thickness 18 of 0.5mm. The resilient retaining ring 22a has an 19 internal diameter of around 12mm, and the cross 20 section of the retaining ring 22a is circular with a 21 radius of about 1.50mm. The overall length of the 22 ring section 30 is around 7.5mm.

24 An alternative end cap 128 is shown in Fig. 5. In 25 this case the heated medical probe 110 depicted in 26 Fig. 5 has a profiled tip with a "distal pip", known 27 in the art as a type "G" probe. Different profiles 28 of tip are provided on such probes to enable 29 different sections of the cervix to be effectively 30 treated. In this case the end cap 128 is shaped to 31 follow the profile of the tip of the heated medical 32 probe 110. By reducing the air gap between the tip

1 and the end cap 128, the efficiency of heat transfer 2 from the probe 110 to the area of the cervix to be 3 treated is increased and thus treatment with a 4 sheathed probe is more effective. It will be 5 understood that the present invention encompasses 6 sheaths with end caps profiled to minimise the air 7 gap between tip and end cap for all the probe types 8 in use.

10 Silicone rubber is used since it displays the 11 desired characteristics of elasticity, durability, 12 heat resistance, good heat conductivity and 13 resilience. The particular material used in this 14 embodiment are WACKER 3003 series (Trade Mark) 15 silicone rubber for the end cap 28 and ring section 16 30, and RHODIA 73791 series (Trade Mark) silicone 17 rubber for the tubular body portion 26. Both of 18 these materials are of a medical grade and tested to 19 U.S.P. (United States Pharmacopeia) Class IV.

21 Once assembled the sheath 20 is ideally packaged in 22 a sterile container or packet (not shown) for use.

24 Fig. 6 shows the sheath 20 in situ on a heated 25 medical probe 10. The sheath 20 covers the heated 26 tip 16 and stem 14. The resilient retaining ring 27 22a grips the stem 16 and impedes slippage of the 28 sheath 20 relative to the probe 16.

30 The sheath 20 provides a disposable protective 31 barrier between the probe 10 and the patient (not 32 shown) and is particularly useful on probes which

1 cannot be sterilised by autoclave. The temperature 2 drop across the silicone rubber material of the 3 sheath is approximately -0. 5 C per mm, giving an 4 overall temperature drop of approximately -0. 25 C 5 between the heated tip 16 and the outer surface of 6 the second closed end 24. Since typical operating 7 temperatures for the probe 10 are in the range of 8 60 C to 120 C, this is a negligible decrease. After 9 use on a patient, the sheath 20 can be disposed of 10 and another fitted when the next patient is to be 11 treated.

13 Further modifications are envisaged which do not 14 depart from the scope of the present invention. The 15 sheath 20 may be packaged with a lubricant to aid 16 insertion. The sheath 20 may also include a 17 disinfecting agent, should further precaution be 18 required.

20 Furthermore, the length of the sheath 20 may be 21 increased to ensure that the handle 12 and power 22 transmission wire are also protected. A typical 23 sheath 20 which covered the handle 12 and power 24 transmission wire would be approximately l90mm in 25 length. Such a sheath is illustrated for reference 26 in Fig. 7.

Claims

1 Claims

3 1. A disposable cover for a heated medical probe 4 comprising a sheath of protective material with 5 a first open end, a second closed end and a 6 body portion.

8

2. A disposable cover for a heated medical probe 9 according to Claim 1 wherein the second closed 10 end is profiled to minimise the air gap between 11 the tip of the heated medical probe and the 12 closed end.

14

3. A disposable cover for a heated medical probe 15 according to Claims 1 or 2 wherein the 16 protective material is capable of withstanding 17 a temperature greater than 100 C.

19

4. A disposable cover for a heated medical probe 20 as claimed in any preceding claim wherein the 21 protective material can withstand a temperature 22 of between 130-150 C for at least 3 minutes.

24

5. A disposable cover for a heated medical probe 25 as claimed in any preceding claim wherein the 26 cover is shaped and dimensioned for fitting 27 over a vaginal probe for use in thermal 28 coagulation therapy of the cervix.

30

6. A disposable cover for a heated medical probe 31 as claimed in any preceding claim wherein the

1 protective material is flexible and has good 2 heat conductance 4

7. A disposable cover for a heated medical probe 5 as claimed in any preceding claim wherein the 6 protective material is a silicone rubber.

8

8. A disposable cover for a heated medical probe 9 as claimed in any preceding claim wherein the 10 cover is substantially circular in cross 11 section. 13

9. A disposable cover for a heated medical probe 14 as claimed in any preceding claim wherein the 15 first open end has a resilient retaining ring 16 for securing it to a probe.

18

10. A disposable cover for a heated medical probe 19 substantially as herein described with 20 reference to Figs. 2 to 4, or Fig. 5, or Fig. 6 21 or Fig. 7.