US5496313A
Expired / Lapsed
US
⏱️ 0.0 years remaining
System for detecting penetration of medical instruments
Assignee: Conmed Corp
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Filing: 1994-09-20
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Granted: 1996-03-05
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Expires: 2014-09-20
Abstract
Abstract A device is provided for use with a medical instrument including a tip which is designed to penetrate the wall of an internal cavity (e.g., the abdomen) of a patient, for detecting when that tip penetrates through the wall. The device includes a source of a medium frequency detection signal and circuitry for coupling the signal to the tip of the medical instrument. The circuitry includes a transformer forming a high Q resonant circuit having an initial value of Q when the medical instrument is not in use. A return path for the signal provides that, in use of the instrument, a circuit is completed through the resonant circuit such that when the tip contacts patient tissue the initial Q of the resonant circuit changes and when the tip penetrates through the patient tissue of the Q of the circuit is restored to the initial value thereon. A detector detects the change in Q of the resonant circuit and produces an output when changed Q is restored to the initial value thereof so as to indicate that the tip has penetrated through the patient tissue.
Inventors
- 👤 John S. Gentelia
- 👤 Ernesto G. Sevilla
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 12:40
CPC Classifications
A; A61; A61B; A61B17/00; A61B17/34; A61B17/3494; A61B18/00; A61B18/04; A61B18/12; A61B18/1206; A61B18/1233; A61B18/14; A61B18/1487; A61B2017/00017; A61B2017/00115; A61B2017/00119; A61B2018/00636; A61B2018/00696; A61B2018/00738
Claims Analysis
Total Claims: 22
Claim 1
Independent Claim
179 words
In combination, a medical instrument including a tip which is designed to penetrate the wall of an internal cavity of a patient, and a device for detecting when the tip penetrates through said wall, said device comprising: a source of a detection signal; means for coupling said signal to the tip of said medical instrument, said coupling means including a high Q resonant circuit having an initial value of Q when the medical instrument is not in use; means for providing a return path for said signal so that, in use of the instrument, a circuit is completed through said resonant circuit such that when said tip contacts patient tissue the initial Q of the resonant circuit changes and when the tip penetrates through the patient tissue the Q of the circuit is restored to said initial value; and detector means for detecting the change in Q of said resonant circuit and for producing an output when changed Q is restored to the initial value thereof so as to indicate that said tip has penetrated through the patient tissue.
Claim 2
Dependent Claim
179 words
In combination, a medical instrument including a tip which is designed to penetrate the wall of an internal cavity of a patient, and a device for detecting when the tip penetrates through said wall, said device comprising: a source of a detection signal; means for coupling said signal to the tip of said medical instrument, said coupling means including a high Q resonant circuit having an initial value of Q when the medical instrument is not in use; means for providing a return path for said signal so that, in use of the instrument, a circuit is completed through said resonant circuit such that when said tip contacts patient tissue the initial Q of the resonant circuit changes and when the tip penetrates through the patient tissue the Q of the circuit is restored to said initial value; and detector means for detecting the change in Q of said resonant circuit and for producing an output when changed Q is restored to the initial value thereof so as to indicate that said tip has penetrated through the patient tissue.
Claim 3
Dependent Claim
32 words
The combination as claimed in claim 1 wherein said medical instrument comprises an electrosurgical generator and wherein said output produced by said detector means provides for cutting off of said electrosurgical generator.
Claim 4
Dependent Claim
33 words
The combination as claimed in claim 1 further comprising indicator means for, responsive to receiving said output from said detector means, providing an indication that said tip has penetrated through the patient tissue.
Claim 5
Dependent Claim
15 words
The combination as claimed in claim 3, wherein said indicator means comprises a light indicator.
Claim 6
Dependent Claim
22 words
The combination as claimed in claim 1 wherein the frequency of said signal produced by said source is a medium frequency signal.
Claim 7
Dependent Claim
23 words
The combination as claimed in claim 5 wherein the frequency of said signal produced by said source is between 5 and 10 kHz.
Claim 8
Dependent Claim
25 words
The combination as claimed in claim 1 wherein the amplitude of said signal produced by said source is less than 1 volts peak to peak.
Claim 9
Dependent Claim
69 words
The combination as claimed in claim 1 wherein said resonant circuit of said coupling means comprises a high Q resonant transformer and said coupling means further comprises a conductor connected to said tip, said transformer including a secondary winding connected in series with said conductor and having a capacitor connected there across so as to form said resonant circuit, and a primary winding connected in series with said source.
Claim 10
Dependent Claim
29 words
The combination as claimed in claim 8 further comprising filtering means for filtering out unwanted signals so as to prevent said unwanted signals from passing to said detector means.
Claim 11
Dependent Claim
45 words
The combination as claimed in claim 9, wherein said medical instrument comprises electrosurgical medical instrument connected to an electrosurgical generator, said filtering means comprises means for filtering out any electrosurgical current coupled back to the detector means and for filtering out noise from other sources.
Claim 12
Dependent Claim
58 words
The combination as claimed in claim 8, wherein said detector means comprises a current detector means, connected in a series circuit with said source and said secondary winding, for producing an output signal related to the current flow in said series circuit, and a logic circuit, responsive to the magnitude of said current flow, for producing said output.
Claim 13
Dependent Claim
16 words
The combination as claimed in claim 1, wherein said detector means comprises a synchronous amplitude detector.
Claim 14
Dependent Claim
26 words
The combination as claimed in claim 1 wherein said means for providing said return path comprises a grounding pad adapted to be applied to a patient.
Claim 15
Dependent Claim
44 words
The combination as claimed in claim 1 wherein said medical instrument comprises an electrosurgical device including an electrosurgical generator, and wherein said resonant circuit includes a capacitor of a value high enough to ensure that substantially all the electrosurgical current flows through said capacitor.
Claim 16
Dependent Claim
26 words
The combination as claimed in said claim 1 wherein said transformer includes a primary winding and said source comprises an oscillator connected to said primary winding.
Claim 17
Dependent Claim
45 words
The combination as claimed in claim 15 wherein said transformer includes first and second secondary windings, said first transformer secondary winding having a capacitor connected there across to form said Q resonant circuit and said second transformer secondary winding being connected to said detector means.
Claim 18
Dependent Claim
28 words
The combination as claimed in claim 16 wherein said instrument comprises an electrosurgical instrument and said device includes a low pass filter connected to said second secondary winding.
Claim 19
Dependent Claim
33 words
The combination as claimed in claim 1 wherein said instrument comprises a mechanical instrument and said mechanical instrument includes a insulated conductor incorporated therein and an end exposed at least near said tip.
Claim 20
Dependent Claim
15 words
The combination as claimed in claim 18 wherein said detector means comprises a level detector.
Claim 21
Dependent Claim
187 words
In combination, an electrosurgical instrument connected to an electrosurgical generator and including a tip which is designed to penetrate the wall of an internal cavity of a patient, and a device for detecting when the tip penetrates through said wall, said device comprising: a source of a detection signal; means for coupling said signal to the tip of said instrument, said coupling means including a high Q resonant circuit having an initial value of Q when the instrument is not in use; means for providing a return path for said signal so that, in use of the instrument, a circuit is completed through said resonant circuit such that when said tip contacts patient tissue the initial Q of the resonant circuit changes and when the tip penetrates through the patient tissue the Q of the circuit is restored to said initial value; and detector means for detecting the change in Q of said resonant circuit and for producing an output, when the changed Q is restored to the initial value thereof indicating that said tip has penetrated through the patient tissue, for cutting off said electrosurgical generator.
Claim 22
Dependent Claim
187 words
In combination, an electrosurgical instrument connected to an electrosurgical generator and including a tip which is designed to penetrate the wall of an internal cavity of a patient, and a device for detecting when the tip penetrates through said wall, said device comprising: a source of a detection signal; means for coupling said signal to the tip of said instrument, said coupling means including a high Q resonant circuit having an initial value of Q when the instrument is not in use; means for providing a return path for said signal so that, in use of the instrument, a circuit is completed through said resonant circuit such that when said tip contacts patient tissue the initial Q of the resonant circuit changes and when the tip penetrates through the patient tissue the Q of the circuit is restored to said initial value; and detector means for detecting the change in Q of said resonant circuit and for producing an output, when the changed Q is restored to the initial value thereof indicating that said tip has penetrated through the patient tissue, for cutting off said electrosurgical generator.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1999-03-05 | 1999-09-04 | 2000-03-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2003-03-05 | 2003-09-04 | 2004-03-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2007-03-05 | 2007-09-04 | 2008-03-05 | $7700.00 | Window Closed / Lapsed |