TECHNIQUES FOR CONTROLLING MEDICAL DEVICE TOOLS

In various embodiments, a medical device includes an instrument head that includes one or more electrode pairs and a medical device tool coupled to a conduit, an impedance bridge, and a processor coupled to the impedance bridge and the conduit. In various embodiments, a method includes recording, at one or more frequencies, one or more impedance measurements associated with one or more electrode pairs included in an instrument head of the medical device; determining, based on the one or more impedance measurements, a tissue type of a portion of tissue contacting the one or more electrode pairs; and performing one or more operations to control a medical device tool included in the instrument head based on the tissue type.

BACKGROUND

Field of the Various Embodiments

Embodiments of the present disclosure relate generally to electronics and medical diagnostic technology and, more specifically, to techniques for controlling medical device tools.

Description of the Related Art

In minimally invasive medical procedures, a healthcare provider typically inserts a medical device into the body of a patient and positions the instrument head of the medical device at a target location, such as the location of a tumor. The instrument head usually includes some form of tool, such as and without limitation, a therapeutic drug delivery tool that delivers a therapeutic drug to the target location, an energy delivery tool that delivers energy (e.g., heat or electricity) to the target location, and/or a tissue sample extraction tool that can be used to extract tissue samples from the target location for further evaluation.

One problem that exists with many conventional medical devices is that operating a medical device tool at a location within the body of a patient that is different than the desired target location can damage otherwise healthy patient tissue and/or result in the target location not being properly treated. Therefore, conventional medical devices oftentimes include various mechanisms for determining the location of an associated medical device tool within the body of a patient. Some example mechanisms include, without limitation, transmitters that transmit signals that can be used for triangulation and ultrasound-visible materials that are visible in ultrasound imaging.

One drawback of the above mechanisms used for determining the location of a medical device tool with the body of a patient is that these mechanisms are oftentimes inaccurate and, accordingly, are insufficient for confirming that a given tool is positioned correctly at a given target location. More specifically, triangulating and ultrasound imaging typically require calibrating the relevant positioning system with respect to both the medical device tool and a mapping of the body of a patient generated, for example, using a medical scan. Errors introduced in the calibration process can produce errors in determining whether the medical device tool is positioned correctly at the target location. Also, any physiological changes within the patient, such as the size, shape, or location of a tumor, between the time when the medical scan is performed and the time when the medical procedure begins can change the target location. Thus, positioning a medical device tool based on a medical scan can result in applying the medical device tool to healthy tissue instead of applying the medical device tool at the target location.

As the foregoing illustrates, what is needed in the art are more effective techniques for controlling medical device tools.

SUMMARY

Embodiments are disclosed for medical devices. In various embodiments, a medical device includes an instrument head that includes one or more electrode pairs and a medical device tool coupled to a conduit, an impedance bridge, and a processor coupled to the impedance bridge and the conduit.

Embodiments are disclosed for controlling a medical device. In various embodiments, a method includes recording, at one or more frequencies, one or more impedance measurements associated with one or more electrode pairs included in an instrument head of the medical device; determining, based on the one or more impedance measurements, a tissue type of a portion of tissue contacting the one or more electrode pairs; and performing one or more operations to control a medical device tool included in the instrument head based on the tissue type.

At least one technical advantage of the disclosed medical device relative to the prior art is that the disclosed medical device confirms that a medical device tool is positioned at a given target location before activating the medical device tool. For example, the disclosed medical device is able to determine that the tissue type of a portion of tissue contacting the electrodes in the instrument head of the medical device matches the expected tissue type at the target location prior to activating the medical device too. In this manner, the disclosed medical device is able to apply different medical device tools to tissue at various target locations more accurately than conventional medical devices. Consequently, the disclosed medical device can be used to perform various procedures, such as and without limitation, delivering therapeutic drugs or energy or extracting tissue samples, at specific target locations more accurately and reliably relative to what can be achieved with conventional medical devices. These technical advantages provide one or more technological advancements over prior art approaches.

DETAILED DESCRIPTION

In the following description, numerous specific details are set forth to provide a more thorough understanding of the various embodiments. However, in the range of embodiments of the concepts includes some embodiments omitting one or more of these specific details.

FIG. 1illustrates a medical device100, according to various embodiments. As shown, the medical device100includes, without limitation, an instrument head108, wires104, and external electrical components106. The instrument head108is positioned at a target location102(e.g., a location of a tumor). While not shown, the instrument head108includes, without limitation, one or more electrode pairs, a conduit, and a medical device tool, such as and without limitation, a therapeutic drug delivery tool that delivers a therapeutic drug to the target location102, an energy delivery tool that delivers energy to the target location102, or a tissue sample extraction tool that extracts a tissue sample from the target location102for further evaluation. The external electrical components106generate current at various frequencies. The wires104conduct the current between the external electrical components106and the instrument head108. The external electrical components106include a processor that measures the impedance of the electrode pair(s) in the instrument head108and a portion of tissue at the target location102that contacts the electrode pair(s). As described in greater detail below, the medical device100determines a tissue type of the portion of tissue contacting the electrode pair(s) based on the impedance measurements. For example and without limitation, based on the impedance measurements, the tissue type of the portion of tissue can be determined to be one of a tumor tissue type or a non-tumor tissue type.

FIG. 2is a more detailed illustration of the instrument head108ofFIG. 1, according to various embodiments. As shown, the instrument head108includes, without limitation, an electrode pair202, a medical device tool204, a catheter206, and wires104. The electrode pair202conducts current, at various frequencies, through a portion of tissue at the target location102that contacts the electrode pair202. The wires104conduct the current between the external electrical components106and the electrode pair202through the catheter206. Although not shown inFIG. 2, the medical device includes a conduit that is coupled to the medical device tool204, as described in greater detail below. In various embodiments, the medical device tool204delivers therapeutic drugs or energy (e.g., carried by a cannula or wires in the catheter206) and/or extracts a tissue sample from a portion of tissue at the target location102for further evaluation. The elements of the instrument head108allow a healthcare provider to deliver therapeutic drugs or energy to the portion of tissue contacting the electrode pair202and/or to extract a tissue sample from the target location102for further evaluation.

FIG. 3is a more detailed illustration of the instrument head108ofFIG. 2, according to various embodiments. As shown, the instrument head108includes, without limitation, a first electrode pair202-1, a second electrode pair202-2, a medical device tool204, and a conduit302. As shown, the instrument head108includes two electrode pairs202-1,202-2; however the term “electrode pair202,” as used herein, is to be understood to include various embodiments with any number of electrode pairs202, including, without limitation, one electrode pair202or three or more electrode pairs202. In various embodiments, the medical device tool204is a therapeutic drug delivery tool that delivers a therapeutic drug, and the conduit302includes one or more therapeutic drug delivery conduits that respectively deliver one or more therapeutic drugs to the therapeutic drug delivery tool. In various embodiments, the medical device tool204is an energy delivery tool, such as and without limitation a cautery, and the conduit includes one or more wires coupling the energy delivery tool to an energy source. In various embodiments, the medical device tool204is a tissue sample extraction tool, and the conduit302includes one or more wires coupling the tissue sample extraction tool to an actuator. In various embodiments, the instrument head108includes any number of medical device tools204, including, without limitation, two or more medical device tools204of a similar type or different types. Further, in various embodiments, the instrument head108includes any number of conduits302, including, without limitation, two or more conduits. In various embodiments, each conduit302is coupled to one or more medical device tools204, and/or each medical device tool204is coupled to one or more conduits302.

FIGS. 4A-Bare detailed illustrations of the electrode pairs202ofFIG. 2in a first configuration, according to various embodiments. As shown, the instrument head108includes, without limitation, a first electrode pair202-1, a second electrode pair202-2, and a medical device tool204. As shown, the electrode pairs202-1,202-2extend in a direction that is substantially parallel to an axis of the medical device tool. As also shown, the medical device tool204resides in between the electrodes of the electrode pairs202-1,202-2when viewed in a direction of an axis of the medical device tool204.

As shown inFIG. 4A, the medical device tool204is in a retracted position, in which tips of the electrodes of the electrode pairs202-1,202-2extend in the direction of the axis farther than a tip of the medical device tool204. For example and without limitation, the medical device tool204can be in the retracted position during deployment and until a processor determines the tissue type of the portion of tissue contacting the electrode pairs202-1,202-2.

As shown inFIG. 4B, the medical device tool204extends from the retracted position to an extended position, in which the tip of the medical device tool204extends in the direction of the axis at least as far as the tips of the electrodes of the electrode pairs202-1,202-2. For example and without limitation, based on determining the tissue type of the portion of tissue contacting the electrode pairs202-1,202-2, a processor can cause the medical device tool204to extend from the retracted position to the extended position (e.g., by activating an actuator that is coupled to the medical device tool204and that causes the medical device tool204to extend from the retracted position to the extended position).

FIGS. 5A-Bare detailed illustrations of the electrode pairs202ofFIG. 2in a second configuration, according to various embodiments. As shown, the instrument head108includes, without limitation, a first electrode pair202-1, a second electrode pair202-2, and a medical device tool204. As also shown, the medical device tool204resides in between the electrodes of the electrode pairs202-1,202-2when viewed in a direction of an axis of the medical device tool204.

As shown inFIG. 5A, the medical device tool204is in a retracted position, in which tips of the electrodes of the electrode pairs202-1,202-2extend in the direction of the axis farther than a tip of the medical device tool204. For example and without limitation, the medical device tool204can be in the retracted position during deployment and until a processor determines the tissue type of the portion of tissue contacting the electrode pairs202-1,202-2.

As shown inFIG. 5B, the medical device tool204extends from the retracted position to an extended position, in which the tip of the medical device tool204extends in the direction of the axis at least as far as the tips of the electrodes of the electrode pairs202-1,202-2. For example and without limitation, based on determining the tissue type of the portion of tissue contacting the electrode pairs202-1,202-2, a processor can cause the medical device tool204to extend from the retracted position to the extended position (e.g., by activating an actuator that is coupled to the medical device tool204).

While not shown, in various embodiments, the electrode pairs202can extend and retract in a corresponding manner as the medical device tool204in the first configuration shown inFIGS. 4A-Bor in the second configuration shown inFIGS. 5A-B. In various embodiments, one or more electrode pairs202can be in an extended position, in which the tips of the electrodes of the electrode pairs202extend in a direction of an axis of the medical device tool204farther than a tip of the medical device tool204. In various embodiments, the electrode pairs202are in the extended position during deployment and until a processor determines the tissue type of the portion of tissue contacting the electrode pairs202. In various embodiments, based on the determined tissue type, the electrode pairs202retracts from the extended position to a retracted position, in which the tip of the medical device tool204extends in the direction of the axis at least as far as the tips of the electrode pairs202. For example and without limitation, based on determining the tissue type of the portion of tissue contacting the electrode pairs202, a processor can cause one or more electrodes pairs to retract from the extended position to the retracted position (e.g., by activating an actuator that is coupled to the one or more electrode pairs202). As shown, the respective electrodes of the electrode pairs202-1,202-2are curved to extend laterally outward with respect to the axis of the medical device tool204. In various embodiments, at least one electrode of the one or more electrode pairs202-1,202-2is made from a flexible material. In various embodiments, a processor can cause the medical device tool204to extend from a retracted position to an extended position and also cause the electrode pairs202to retract from an extended position to a retracted position. For example and without limitation, based on determining the tissue type of the portion of tissue, a processor can activate an actuator to cause the medical device tool204to extend, and also activate an actuator to cause the electrode pairs202to retract.

As technical advantages of these various embodiments, in various embodiments and without limitation, causing the medical device tool204to be in a retracted position until confirming that the medical device100is positioned at the target location102, and then to extend, can prevent the medical device tool204from contacting other tissue of the patient. Similarly, causing the electrode pairs202to be in an extended position until confirming that the medical device100is positioned at the target location102, and then to retract, can prevent the medical device tool204from contacting other tissue of the patient. Alternatively or additionally, in various embodiments and without limitation, causing the electrode pairs202to retract, and/or causing the medical device tool204to extend, can prevent the medical device tool204from altering the impedance measurements of the portion of tissue at the target location102by the electrode pairs202. Alternatively or additionally, in various embodiments and without limitation, causing the electrode pairs202to retract, and/or causing the medical device tool204to extend, can prevent the medical device tool204from contacting the electrode pairs202during operations (e.g., while the medical device tool204delivers a therapeutic drug, delivers energy, extracts a tissue sample, or the like). Further, in various embodiments in which electrodes extend laterally outward with respect to the axis of the medical device tool204, extending the electrode pairs202can cause the electrodes to contact a larger portion of tissue (e.g., impedance measurements of a large tumor), while retracting the electrode pairs202can cause the electrodes to contact a smaller portion of tissue (e.g., impedance measurements of a small tumor).

FIG. 6is a more detailed illustration of the external electrical components ofFIG. 1, according to various embodiments. As shown, the external electrical components106include wires104, an amplifier602, an impedance bridge604, and a processor606. The wires104conduct current at various frequencies between an electrode pair202and the external electrical components106. In various embodiments, the amplifier602is an analog interface amplifier that amplifies a supplied voltage and/or a return voltage while the wires104conduct current at various frequencies between the impedance bridge604and the electrode pair202. In various embodiments, the impedance bridge604is an impedance load that the processor606measures to determine an impedance of a circuit including the impedance bridge604, the amplifier602, and the electrode pair202. The processor606generates frequencies for a current that the wires104conduct between the impedance bridge604and the electrode pair202.

While the wires104conduct current at various frequencies, the processor606records one or more impedance measurements608of the circuit including the electrode pair202. The processor606determines a tissue type610of a portion of tissue contacting the electrode pair202based on the impedance measurements608. In various embodiments, the processor606determines the tissue type610by comparing the impedance measurements608with one or more characteristic impedance measurements associated with one or more tissue types. For example and without limitation, based on the comparing, the processor606can determine which tissue type is associated with characteristic impedance measurements that are closest to the impedance measurements of the portion of tissue contacting the electrode pair202. In various embodiments, the processor606can determine a Cole relaxation frequency of the portion of tissue based on the impedance measurements608, and can compare the Cole relaxation frequency to one or more characteristic Cole relaxation frequencies of one or more tissue types. The Cole relaxation frequency corresponds to a frequency associated with a greatest impedance measurement608included in the one or more impedance measurements608. In various embodiments, the Cole relaxation frequency is a frequency of a maximum normalized impedance measurement of the portion of tissue contacting the electrode pair202. For example and without limitation, based on a Cole relaxation frequency below a threshold frequency (e.g., 105Hz), the processor606can determine that the portion of tissue contacting the electrode pair202is a non-tumor tissue type. Similarly, for example and without limitation, based on a Cole relaxation frequency above the threshold frequency, the processor606can determine that the portion of tissue contacting the electrode pair202is a tumor tissue type.

In various embodiments, the processor606performs one or more operations612to control the medical device tool204based on the determined tissue type610. For example and without limitation, in various embodiments in which the medical device tool204is a therapeutic drug delivery tool, the processor606can perform operations612that include activating the therapeutic drug delivery tool to deliver one or more therapeutic drugs to the portion of tissue. For example and without limitation, in various embodiments in which the medical device tool204is an energy delivery tool, the processor606can perform operations612that include activating the energy delivery tool to deliver energy to the portion of tissue. For example and without limitation, in various embodiments in which the medical device tool204is a tissue sample extraction tool, the processor606can perform operations612that include activating the tissue sample extraction tool to extract a tissue sample from the portion of tissue. For example and without limitation, in various embodiments in which the medical device tool204can extend, the processor606can perform operations612that include causing the medical device tool204to extend from a retracted position to an extended position (e.g., by activating an actuator that is coupled to the medical device tool204). For example and without limitation, in various embodiments in which the electrode pair202can retract, the processor606can perform operations612that include causing the electrode pair202to retract from an extended position to a retracted position (e.g., by activating an actuator that is coupled to the electrode pair202).

In various embodiments, based on determining the tissue type610, the processor606presents an indication of the tissue type610of the portion of tissue contacting the electrode pair202. For example and without limitation, the processor606can indicate the tissue type610using a visual output (e.g., a light-emitting diode, a liquid crystal display, or the like) and/or an audio output (e.g., a speaker, a buzzer, or the like). In various embodiments, based on determining the tissue type610, the processor606presents an indication that the determined tissue type610matches the tissue type of tissue at a target location102. For example and without limitation, where the target location102is a tumor, the processor606can indicate that a determined tumor tissue type matches the tissue type of the tissue at the target location102. Presenting the indication can inform a user of the medical device100that the instrument head is at the target location102. Further, in various embodiments, the processor606performs the one or more operations612to control the medical device tool204based on presenting the indication that the determined tissue type610matches the tissue type of tissue at a target location102and receiving a signal to activate the medical device tool204.

FIG. 7is a more detailed illustration of the medical device100ofFIG. 1, according to various embodiments. As shown, the medical device100includes an instrument head108and external electrical components106. As shown, the instrument head108includes an electrode pair202that is coupled to the external electrical components106by wires104. In various embodiments, the instrument head108includes, without limitation, two or more electrode pairs202, which can be coupled to the external electrical components106by one wire104or by respective wires of a plurality of wires104. As shown, the instrument head108also includes a medical device tool204, such as and without limitation, a therapeutic drug delivery tool, an energy delivery tool, or a tissue sample extraction tool. In various embodiments, the instrument head10includes, without limitation, two or more medical device tools204, which can be of one kind or of different kinds.

As shown, the external electrical components106include an amplifier602, an impedance bridge604, and a processor606. The amplifier602amplifies a supplied voltage and/or a return voltage while the wires104conduct current at various frequencies between the impedance bridge604and the electrode pair202. The impedance bridge604is an impedance load that the processor606measures to determine an impedance of a circuit including the impedance bridge604, the amplifier602, the wires104, and the electrode pair202. The processor606records, at various frequencies, one or more impedance measurements608. The processor606determines a tissue type610of a portion of tissue contacting the electrode pair202based on the impedance measurements608. In various embodiments and without limitation, the processor606determines the tissue type based on a Cole relaxation frequency of the portion of tissue contacting the electrode pair202. In various embodiments and without limitation, the processor606determines the tissue type610of the portion of tissue as one of a tumor tissue type or a non-tumor tissue type. In various embodiments and without limitation, the processor606determines that the tissue type610matches the tissue type of tissue at the target location102, which indicates or confirms that the instrument head108is positioned at the target location102. For example and without limitation, if the target location102is a tumor, the processor606can determine whether the instrument head108is positioned at the target location102by determining that the tissue type610is a tumor tissue type.

As shown, the processor606is coupled to a conduit302of the medical device tool204. Based on the determined tissue type610, the processor606performs one or more operations612to control the medical device tool204. In various embodiments and without limitation, the medical device tool204is a therapeutic drug delivery tool, and the processor606performs an operation612of causing the medical device tool204to deliver one or more therapeutic drugs to tissue at the target location102. For example and without limitation, the processor606can cause one or more therapeutic drugs through one or more drug delivery conduits to and through the therapeutic drug delivery tool. In various embodiments and without limitation, the medical device tool204is an energy delivery tool, and the processor606performs an operation612of causing the conduit302and the medical device tool204to deliver energy to tissue at the target location102. For example and without limitation, the processor606can current to be conducted through wires in the conduit302to and through the energy delivery tool. In various embodiments and without limitation, the medical device tool204is a tissue sample extraction tool, and the processor606performs an operation612of causing the tissue sample extraction tool to extract a tissue sample from tissue at the target location102. For example and without limitation, the external electrical components106can include an actuator coupled to the tissue sample extraction tool by wires in the conduit302, and the processor606can activate the actuator to cause the tissue sample extraction tool to extract the tissue sample.

In various embodiments, the medical device100reports the determined tissue type610to a user of the medical device100. For example and without limitation, the medical device100can display an indicator of the determined tissue type610using a visual output (e.g., a liquid crystal display (LCD), a light-emitting diode (LED) display to present a visual indication of the tissue type610, such as a light, symbol, text, graphic, or the like) and/or an audio indication of the determined tissue type610using an audio output (e.g., using a speaker, buzzer, or the like to present an audio cue of the tissue type610, such as a spoken description, sound effect, or the like). In various embodiments and without limitation, the processor606can present an indication that the determined tissue type610matches the tissue type of tissue at the target location102(e.g., using a visual output, an audio output, or the like).

FIG. 8is a flow diagram of method steps for controlling the medical device100ofFIG. 1, according to various embodiments. Although the method steps are described in conjunction with the systems ofFIGS. 1-7, persons skilled in the art will understand that any system configured to perform the method steps, in any order, falls within the scope of the present invention.

As shown, a method800begins at step802, where a processor606records, at one or more frequencies, one or more impedance measurements608associated with one or more electrode pairs202included in an instrument head108of the medical device100. In various embodiments and without limitation, the processor606determines a Cole relaxation frequency of a portion of tissue contacting the one or more electrode pairs202in the instrument head108, e.g., as a frequency of a maximum normalized impedance measurement of the portion of tissue contacting the electrode pair202.

At step804, the processor606determines, based on the one or more impedance measurements608, a tissue type610of a portion of tissue contacting the one or more electrode pairs202. In various embodiments and without limitation, the processor606determines the tissue type as one of a tumor tissue type or a non-tumor tissue type. In various embodiments and without limitation, the processor606determines whether the tissue type of the portion of tissue matches a tissue type of tissue at a target location102. In various embodiments, the processor606determines the tissue type610by comparing the impedance measurements608to one or more characteristic impedance measurements associated with one or more tissue types. In various embodiments and without limitation, the processor606determines whether the determined tissue type610matches a tissue type of tissue at a target location102(e.g., in order to determine whether the instrument head108is positioned at the target location102).

At step806, the processor606performs one or more operations612to control a medical device tool204included in the instrument head108based on the tissue type610. For example and without limitation, based on the determined tissue type610, the processor606can perform operations612that cause a therapeutic medical device tool to deliver a therapeutic drug to tissue at the target location102; that cause an energy device tool to deliver energy to tissue at the target location102; and/or to cause a tissue sample extraction tool to extract a tissue sample from tissue at the target location102. In various embodiments, the processor606can use one or more of a visual output or an audio output to present an indication of the determined tissue type610of the portion of tissue, and/or an indication that the determined tissue type610matches the tissue type of tissue at a target location102.

In sum, the disclosed medical device measures the impedance of a portion of tissue in contact with the electrodes included in the instrument head and residing at a target location. The medical device further determines the tissue type of the portion of tissue based on the measured impedance. Based on the tissue type, the medical device controls a medical device tool in the instrument head and ensures that the medical device tool is applied properly to the portion of tissue at the target location. The disclosed approach advantageously results in the medical device applying the medical device tool to tissue at a target location while avoiding portions of tissue residing at other locations.

At least one technical advantage of the disclosed medical device relative to the prior art is that the disclosed medical device confirms that a medical device tool is positioned at a given target location before activating the medical device tool. For example, the disclosed medical device is able to determine that the tissue type of a portion of tissue contacting the electrodes in the instrument head of the medical device matches the expected tissue type at the target location prior to activating the medical device too. In this manner, the disclosed medical device is able to apply different medical device tools to tissue at various target locations more accurately than conventional medical devices. Consequently, the disclosed medical device can be used to perform various procedures, such as and without limitation, delivering therapeutic drugs or energy or extracting tissue samples, at specific target locations more accurately and reliably relative to what can be achieved with conventional medical devices. These technical advantages provide one or more technological advancements over prior art approaches.

1. In some embodiments, a medical device comprises an instrument head that includes one or more electrode pairs, and a medical device tool coupled to a conduit; an impedance bridge; and a processor coupled to the impedance bridge and the conduit.

2. The medical device of clause 1, wherein the medical device tool comprises a therapeutic drug delivery tool, and the conduit includes one or more therapeutic drug delivery conduits.

3. The medical device of clauses 1 or 2, wherein the medical device tool comprises an energy delivery tool, and the conduit includes one or more wires coupling the energy delivery tool to an energy source.

4. The medical device of any of clauses 1-3, wherein the medical device tool comprises a tissue sample extraction tool, and the conduit includes one or more wires coupling the tissue sample extraction tool to an actuator.

5. The medical device of any of clauses 1-4, wherein the medical device tool resides in between the electrodes of at least one electrode pair.

6. The medical device of any of clauses 1-5, wherein at least one electrode of a given electrode pair extends laterally outward with respect to an axis of the medical device tool.

7. The medical device of any of clauses 1-6, wherein at least one electrode of a given electrode pair is made from a flexible material.

8. The medical device of any of clauses 1-7, further comprising one or more actuators that are coupled to a given electrode pair.

9. The medical device of any of clauses 1-8, further comprising an actuator coupled to the medical device tool that causes the medical device tool to extend from a retracted position to an extended position.

10. In some embodiments, a method for controlling a medical device comprises recording, at one or more frequencies, one or more impedance measurements associated with one or more electrode pairs included in an instrument head of the medical device; determining, based on the one or more impedance measurements, a tissue type of a portion of tissue contacting the one or more electrode pairs; and performing one or more operations to control a medical device tool included in the instrument head based on the tissue type.

11. The method of clause 10, wherein determining the tissue type comprises comparing the one or more impedance measurements to one or more characteristic impedance measurements associated with one or more tissue types.

12. The method of clauses 10 or 11, wherein determining the tissue type comprises determining a Cole relaxation frequency of the portion of tissue based on the one or more impedance measurements, and comparing the Cole relaxation frequency of the portion of tissue to one or more characteristic Cole relaxation frequencies of one or more tissue types.

13. The method of any of clauses 10-12, wherein the Cole relaxation frequency corresponds to a frequency associated with a greatest impedance measurement included in the one or more impedance measurements.

14. The method of any of clauses 10-13, wherein determining the tissue type comprises determining a tumor tissue type based on the Cole relaxation frequency of the portion of tissue being above a threshold frequency, or determining a non-tumor tissue type based on the Cole relaxation frequency of the portion of tissue being below the threshold frequency.

15. The method of any of clauses 10-14, wherein the medical device tool comprises a therapeutic drug delivery tool, and performing the one or more operations to control the medical device tool comprises activating the therapeutic drug delivery tool to deliver one or more therapeutic drugs to the portion of tissue.

16. The method of any of clauses 10-15, wherein the medical device tool comprises an energy delivery tool, and performing the one or more operations to control the medical device tool comprises activating the energy delivery tool to deliver energy to the portion of tissue.

17. The method of any of clauses 10-16, wherein the medical device tool is a tissue sample extraction tool, and performing the one or more operations comprises activating the tissue sample extraction tool to extract a tissue sample from the portion of tissue.

18. The method of any of clauses 10-17, wherein performing the one or more operations to control the medical device tool at least one of, causing the medical device tool to extend from a retracted position to an extended position, or causing the electrodes of at least one electrode pair to retract from an extended position to a retracted position.

19. The method of any of clauses 10-18, further comprising outputting at least one of a visual indication or an audio indication of the tissue type of the portion of tissue.

20. The method of any of clauses 10-19, further comprising outputting at least one of a visual indication or an audio indication that the tissue type of the portion of tissue matches the tissue type of tissue at a target location.