GB2094636A
Expired / Lapsed
GB
⏱️ 0.0 years remaining
A cryosurgical probe
Assignee: Spembly Ltd
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Filing: 1982-03-04
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Granted: —
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Expires: 2002-03-04
Abstract
Abstract A cryosurgical probe having a tip portion E designed to control iceball formation and thus the freezing efficiency of the probe. The probe operates by the Joule-Thompson effect of gas cooling when expanded through a restriction J. In known probes, after cooling in this way, the gas is immediately vented to exhaust so reducing the dwell time of the gas in the tip. The probe disclosed is designed such that the cooled gas after passing through the restriction travels along a terminating passage 61 in heat exchange relationship with the wall of the tip before being vented to exhaust. The length of the terminating passage formed in the tip increases the dwell time there thus enabling better control of iceball formation. Moreover the length of the terminating passage is made adjustable, so that the iceball shape formed at the tip, between the restriction and the extremity of the tip, can be varied. <IMAGE>
Inventors
No inventors recorded.
Bibliographic Details
Application Number
—
Jurisdiction
GB
Data Source
google_patents
Last Synchronized
2026-10-23 12:46
CPC Classifications
F; F25; F25B; F25B9/00; F25B9/02; A; A61; A61B; A61B18/00; A61B18/02; F25B2500/00; F25B2500/01
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
96 words
A cryosurgical probe comprising a probe body, a hollow tip portion of the probe body of high thermal conductivity, a delivery passage for pressurised gas to said hollow tip portion, an exhaust passage for discharging gas from the tip portion and being surrounded by said delivery passage, and a restriction in said delivery passage forming a terminating portion of said delivery passage within said hollow tip portion and downstream of said restriction, thereby to cause cooling of the gas by the
Joule-Thompson effect in passing through the restriction into said terminating part of said delivery passage.
Claim 2
Dependent Claim
96 words
A cryosurgical probe comprising a probe body, a hollow tip portion of the probe body of high thermal conductivity, a delivery passage for pressurised gas to said hollow tip portion, an exhaust passage for discharging gas from the tip portion and being surrounded by said delivery passage, and a restriction in said delivery passage forming a terminating portion of said delivery passage within said hollow tip portion and downstream of said restriction, thereby to cause cooling of the gas by the
Joule-Thompson effect in passing through the restriction into said terminating part of said delivery passage.
Claim 3
Dependent Claim
37 words
A cryosurgical probe as claimed in Claim 1 wherein a conduit acting as said exhaust passage extends within the probe body to open out into said hollow tip portion, said delivery passage being formed around said conduit.
Claim 4
Dependent Claim
96 words
A cryosurgical probe as claimed in Claim 2 wherein the main probe body is sleeved to said hollow tip portion to form a double wall section of the probe, the inner wall of which, being of the material of said hollow tip portion, is around an end section of said conduit and has an extremity which is swaged over said end section to form said restriction, with said terminating portion of said delivery passage being between the outer wall of the said end section and said inner wall of the tip portion downstream of said restriction.
Claim 5
Dependent Claim
41 words
A cryosurgical probe as claimed in Claim 3 wherein the swaged extremity of said inner wall is provided with diametrically opposed dimples or grooves to permit the probe to be calibrated in terms of required gas flow rate through said restriction.
Claim 6
Dependent Claim
37 words
A cryosurgical probe as claimed in Claim 4 wherein said conduit is formed of a main conduit part and an extension conduit part of smaller crosssection brazed or glued thereto at a point upstream of said restriction.
Claim 7
Dependent Claim
27 words
Acryosurgical probe as claimed in Claim 2 wherein said conduit is adjustably positioned to permit variation of the length or said end section downstream of said restriction.
Claim 8
Dependent Claim
88 words
A cryosurgical probe as claimed in Claim 2 wherein said conduit is formed of a main conduit part and an extension conduit part of smaller crosssection brazed or glued thereto, the end of the main conduit part at the join between the main and extension conduit parts being belled-out to engage the inner wall of said probe body thereby to form said restriction in said delivery passage and said terminating passage between said extension conduit part and the inner wall of said probe body downstream of said restriction.
Claim 9
Dependent Claim
38 words
A cryosurgical probe as claimed in Claim 7 wherein the belled-out portion is provided with diametrically opposed cut-outs for calibrating the probe in terms of determining the flow rate of gas in the probe through said delivery passage.
Claim 10
Independent Claim
24 words
A device as claimed in Claims 5 or 7 wherein a thermocouple extends within said conduit to within the tip portion of said probe.
Claim 11
Dependent Claim
23 words
A cryosurgical probe as claimed in Claim 2 wherein said probe body, said tip portion and said conduit are made of stainless steel.
References Cited (Backward Citations)
No citation records indexed.
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