Patent Description:
A large number of people suffer from lung disease, such as emphysema, chronic obstructive pulmonary disease ("COPD"), asthma, or cancer. Diseases such as emphysema result in poor airflow due to a breakdown of lung tissues. In patients suffering from emphysema the alveoli are no longer elastic and can become enlarged due to walls between the alveoli breaking down. As a result, the alveoli lose their shape and become floppy. This damage from emphysema leads to fewer and larger air sacs instead of many tiny ones. These large alveoli may be called bullae. One result of this breakdown of the alveoli is that the volume of gas exchange that can occur is reduced as the surface area of these fewer enlarged alveoli is less than the many smaller alveoli. Additionally, the weakened floppy alveoli easily expand during an inhalation. Because of the weakened condition, the air having entered the weakened alveoli cannot be forced out of the lungs during exhalation. Deoxygenated air is trapped inside of the damaged floppy alveoli. Additionally, lung diseases may result in build up or increased deposition of connective tissue within the lungs. Such build up or increased deposition of connective tissue increases density of lung tissue making it more difficult to penetrate.

Sometimes lesions form within the damaged floppy alveoli. The lesions that form within the alveoli also comprise the trapped air inside of the damaged floppy alveoli. Therefore, any medical instrument that is inserted into the lesion is then surrounded by air that is within the lesions. Additionally, lesions may also form within areas of increased connective tissue or scarring as well, resulting in increasing the amount of force necessary to insert a medical instrument through the tissue and into the lesion. Furthermore, since tissue does not divide along a straight line, inserting a medical instrument into tissue or penetrating a medical instrument through tissue often results in air-gaps being created between the tissue and the instrument itself. Further, the mere act of inserting an instrument into a target area must, necessarily, divide the tissue resulting in space for air to collect the instruments.

In procedures that involve using medical instruments that deliver energy, such as microwave energy, or other forms of therapies, such as chemotherapy, to attack a lesion, the air that surrounds the medical instrument creates numerous problems including inefficient delivery of energy or drug to attack the lesions. In this context, the technical teaching disclosed in document <CIT> Al is acknowledged.

Further this air creates passageways for leakage of therapeutic substance away from the intended site. Additionally, the air from the lesions also affects medical devices that use ultrasound to generate images, resulting in poor or inaccurate images of the tissue of the lesion and surrounding the lesion. The present disclosure seeks to address at least some of the above-identified air related problems.

Methods mentioned hereinafter do not form part of the invention The present disclosure is directed in part to a system including an extended working channel defining an elongated passageway and adapted to extend through the bronchoscope and into a luminal network, an opening operably associated with the extended working channel and in fluid communication with the luminal network and medical instrument configured for insertion through the extended working channel. During operation, apposition of tissue in the direction of the extended working channel isolates at least a portion of a luminal network in which the extended working channel is inserted.

The opening may be connected to a vacuum source, such as a syringe. The vacuum source may generate a threshold amount of suction to remove air from at least a portion of a luminal network in which the extended working channel is inserted. A consistent zone may be formed around the medical instrument by suctioning the air from at least a portion of a luminal network in which the extended working channel is inserted using the opening operably associated with the extended working channel.

The opening may be connected to a liquid source, which provides for example saline. The system may include a valve in fluid communication with the liquid source and the opening such as a duckbill valve. A consistent zone may be formed around the medical instrument by injecting fluid from the fluid source through the opening in the extended working channel and into at least a portion of a luminal network in which the extended working channel is inserted.

The system may further include one or more balloons operably associated with the extended working channel to secure the extended working channel within the luminal network and isolate at least a portion of the luminal network. The opening may be located proximal of the distal end of the extended working channel.

A further aspect of the present disclosure is directed to a method including navigating an extended working channel through a bronchoscope to a target within a luminal network, inserting a medical instrument into the extended working channel; and apposing tissue on at least a portion of the extended working channel or medical instrument to isolate at least a portion of a luminal network in which the extended working channel is inserted.

Vacuum may be applied to the extended working channel to draw air from the luminal network to an opening formed in the extended working channel. The vacuum may draw air away from the distal end of the medical instrument. The method may include the generation of a consistent zone around the medical instrument.

A further aspect of the present disclosure is directed to a system including a medical instrument with a handle and an ablation probe, the ablation probe includes a microwave ablation antenna, a catheter attached to the medical instrument, an opening of the catheter is connected to an external source. During operation, apposition of a target tissue in a patient with the medical instrument isolates at least the portion of a target area in the patient including the target tissue.

In another aspect of the present disclosure, the handle of the medical instrument includes a housing unit and the catheter is configured to extend from the housing unit and retract into the housing unit.

In another aspect of the present disclosure, the catheter surrounds the ablation probe of the medical instrument.

In yet another aspect of the present disclosure, the external source is a vacuum source.

In yet another aspect of the present disclosure, the external source is a liquid source.

Various aspects and features of the present disclosure are described herein below with references to the drawings, wherein:.

The present disclosure is directed to devices and systems for enhanced treatment options and effectiveness of surgical procedure. Embodiments of the present disclosure are now described in detail with reference to the drawings in which like reference numerals designate identical or corresponding elements in each of the several views. As used herein, the term "clinician" refers to a doctor, a nurse, or any other care provider and may include support personnel. Throughout this description, the term "proximal" will refer to the portion of the device or component thereof that is closer to the clinician and the term "distal" will refer to the portion of the device or component thereof that is farther from the clinician. Throughout this description, the term "consistent field" or "consistent zone" refers to an area in space within the body of a patient, where the permittivity of the area to microwave energy is less than the permittivity of air to microwave energy. Additionally, in the drawings and in the description that follows, terms such as front, rear, upper, lower, top, bottom, and similar directional terms are used simply for convenience of description and are not intended to limit the disclosure. In the following description, well-known functions or constructions are not described in detail to avoid obscuring the present disclosure in unnecessary detail.

Lesions may form in various regions within the body. Some lesions may be accessible within an area of the body that is reachable using the airways of the patient. To approach or treat lesions that are within an area of the body of the patient that is reachable using the airways of the patient, a clinician may navigate a medical instrument, such as an ablation catheter; to the area affected by the lesion using airway based medical navigation procedures. But lesions may form in areas of the body that are difficult or impossible to reach by navigating only within the airways of the patient. To approach or treat lesions that are outside of the airways, a clinician may navigate a medical instrument, such as a biopsy or treatment catheter to the area affected by the lesion or the desired surgical site using off-airway surgical procedures involving puncturing a portion of the tissue of luminal network of the lungs (e.g. airways) and tunneling to the desired surgical site. This tunneling may be done either using a separate tunneling device, or in some instances using the medical instrument itself.

Lesions typically have different tissue density than tissue not affected by the disease. Each lesion may have a different tissue density from other lesions. For example, some lesions such as leipidic adenocarcinomas are partially solid. Lesions, as described herein, may be a nonspecific finding on a computed tomography (CT) scans typically described as ground-glass opacification or opacity. Further, scar tissue can give rise to new malignancies thus necessitating biopsy and treatment of this denser tissue. Still further, lesions may also be partially filled with air. Therefore, puncturing a lesion for treatment or performing a biopsy of the lesion may result in the medical instrument being surrounded by the air of the lesion potentially affecting the effectiveness.

When considering effective utilization of medical instruments, particularly treatment instruments such as microwave ablation or chemotherapy implements and visualization diagnostics such as ultrasound, it is important to note that a medical instrument that does not create apposition with the surrounding tissue will be less effective. As noted above, some of the targets themselves have air entrained within them as a consequence of the type of cancer (e.g., leipidic in situ adenoca), or location such as when diagnosing and treating a cavity lesion, such as infectious cavities. This effectiveness reduction is created by additional material interfaces between the medical instrument and the tissue to be treated. For example, when treating in the airways, air (a common insulator) adversely affects the efficiency of the energy transfer from the microwave radiator to the target. Additionally, the air in the lesions creates problems for ultrasound devices in producing images as ultrasound energy, like microwave energy, does not traverse air well. The result is an inefficient zone of treatment or inaccurate depiction of the tissue involved in the surgery, both of which may cause issues for clinicians in successfully treating the lesions.

The present disclosure provides apparatus, systems and techniques for creating a tissue-to-tool interface between the medical instrument and the lesion or the tissue affected by the lesion. The tissue-to-tool interface improves the efficiency of the zone of treatment, resulting in a more consistent field or consistent zone around the medical instrument. The improved field around the medical instrument allows for a more efficient delivery of energy or chemical therapies. Additionally, the improved field increases the accuracy and clarity of images of ultrasound devices, improving the visualization of the procedure for the clinicians.

In accordance with the present disclosure, one way to improve the consistent field or zone around the energy or treatment source is by the apposition of the target tissue to the medical instrument. With the apposition the target tissue against the medical instrument reduces the leakage of therapeutic substance away from the medical instrument or source or away from the target area can be minimized. Further, the energy transfer from modalities such as microwave, cryogenic, and RF ablation can be increased due to a reduction in resistance caused by the removal of air, which commonly acts as an insulator limiting efficient energy transfer. Still further, and for similar reasons apposition of the tissue against the medical instrument improves imaging clarity and accuracy.

In some embodiments, the tissue-to-tool interface between the medical instrument and the tissue may be created by suctioning air around the medical instrument such that the tissue is drawn closer to the medical instrument. The vacuum used in suctioning the air around medical instrument may be sufficient to draw the tissue closer to the medical instrument, however, may not be sufficient to induce atelectasis (i.e., the complete collapse of the tissue as a result of the withdrawal of the air in a given portion of the organ). In some embodiments, the tissue-to-tool interface between the medical instrument and the tissue may be created by injecting fluid that provides a more consistent environment or zone around medical instrument for delivering energy. Similarly, in other embodiments the apposition of the tissue to the therapy or treatment device can limit the ability of fluid or gas therapies or treatments from dispersing beyond the intended treatment site. Further, in some embodiments, images captured around the surgical site or the medical instrument may be projected on to one or more video monitors.

<FIG> depicts an electromagnetic navigation (EMN) system <NUM> is provided in accordance with the present disclosure. EMN system <NUM> may be employed in accordance with various example embodiments herein. An example of the EMN system is the ELECTROMAGNETIC NAVIGATION BRONCHOSCOPY® system currently sold by Medtronic, Inc. The specific number of components of the system <NUM> depicted in <FIG> and the arrangement and configuration thereof are provided for illustrative purposes only, and should be construed as limiting. EMN system <NUM> may be used to plan a pathway to target tissue, navigate a positioning assembly to the target tissue, navigate a biopsy tool to the target tissue to obtain a tissue sample from the target tissue and use the biopsy tool to digitally mark the location where the tissue sample was obtained, and place one or more echogenic markers at or around the target.

EMN system <NUM> includes an operating table <NUM> configured to support a patient, a bronchoscope <NUM> configured for insertion through the patient's mouth and/or nose into the patient's airways, monitoring equipment <NUM> coupled to bronchoscope <NUM> for displaying video images received from bronchoscope <NUM>, a tracking system <NUM> including a tracking module <NUM>, a plurality of reference sensors <NUM>, an electromagnetic field generator <NUM>, and a workstation <NUM> including software and/or hardware used to facilitate pathway planning, identification of target tissue, navigation to target tissue, and digitally marking the biopsy location.

Catheter guide assemblies may be used with EMN systems. <FIG> depicts two types of catheter guide assemblies <NUM>, <NUM>. Catheter guide assemblies <NUM>, <NUM> are usable with the EMN system <NUM> and share a number of common components. Each of the catheter guide assemblies <NUM>, <NUM> includes a handle <NUM>, which is connected to an extended working channel (EWC) <NUM>. The EWC <NUM> may be sized for placement into the working channel of a bronchoscope <NUM>. In operation, a locatable guide (LG) <NUM>, including an electromagnetic (EM) sensor <NUM>, is inserted into the EWC <NUM> and locked into position such that the sensor <NUM> extends a desired distance beyond the distal tip of the EWC <NUM>.

The location of the EM sensor <NUM>, and thus the distal end of the EWC <NUM>, within an electromagnetic field generated by the electromagnetic field generator <NUM> can be derived by the tracking module <NUM>, and the workstation <NUM>. Catheter guide assemblies <NUM>, <NUM> have different operating mechanisms. In one embodiment, catheter guide assemblies <NUM>, <NUM> contain a handle <NUM> that can be manipulated by rotation and compression to steer the distal tip <NUM> of the LG <NUM>, extended working channel <NUM>.

Valve <NUM> may be attached to EWC <NUM>. In some embodiments, valve <NUM> may be used to suction air out of the patient's airways. A vacuum source (not shown) may be attached to valve <NUM> and may be used in suctioning air out of a certain area within the patient's airway. In some embodiments, valve <NUM> may permit injecting fluid, such saline, into a certain area within the patient. The area within the patient to which the fluid is injected may be based on the area where a medical instrument is to be used. In some embodiments, valve <NUM> may be attached perpendicularly to EWC <NUM>. Additional details of valve <NUM> are described with respect to <FIG>.

In some embodiments, one or more balloons (see e.g. <FIG>) may extend from EWC <NUM>. The balloons may extend laterally from EWC <NUM>. A balloon may be located proximal to the distal end of the EWC <NUM>. A balloon may also be located distally from the distal end of the EWC <NUM>. The one or more balloons may be used to seal at least a portion of an airway. Upon sealing a portion of the airway, a medical instrument may be inserted in to EWC <NUM> and extended through the distal end of EWC <NUM> and to the target tissue.

In further embodiments, a port or opening may be located proximal to the distal end of EWC <NUM>. The opening may be used to suction air from the space around the distal end of EWC <NUM> or to suction air surrounding a medical instrument. By suctioning a sufficient amount of air out from the distal end of EWC <NUM> or surrounding the medical instrument, the medical instrument is placed in apposition with the target or surgical site. Additional details of the opening or port proximal to the distal end of a EWC are described in <FIG>.

For a more detailed description of the catheter guide assemblies <NUM>, <NUM> and valves attached to extended working channels reference is made to commonly-owned <CIT>, and <CIT>.

As illustrated in <FIG>, the patient is shown lying on an operating table <NUM> with a bronchoscope <NUM> inserted through the patient's mouth and into the patient's airways. Bronchoscope <NUM> includes a source of illumination and a video imaging system (not explicitly shown) and is coupled to monitoring equipment <NUM>, e.g., a video display, for displaying the video images received from the video imaging system of bronchoscope <NUM>.

Catheter guide assemblies <NUM>, <NUM> including LG <NUM> and EWC <NUM> are configured for insertion through a working channel of bronchoscope <NUM> into the patient's airways (although the catheter guide assemblies <NUM>, <NUM> may alternatively be used without bronchoscope <NUM>). The LG <NUM> and EWC <NUM> are selectively lockable relative to one another via a locking mechanism <NUM>. A six degrees-of-freedom electromagnetic tracking system <NUM>, e.g., similar to those disclosed in <CIT> and published <CIT> and <CIT>. Tracking system <NUM> is configured for use with catheter guide assemblies <NUM>, <NUM> to track the position of the EM sensor <NUM> as it moves in conjunction with the EWC <NUM> through the airways of the patient, as detailed below.

As shown in <FIG>, electromagnetic field generator <NUM> is positioned beneath the patient. Electromagnetic field generator <NUM> and the plurality of reference sensors <NUM> are interconnected with tracking module <NUM>, which derives the location of each reference sensor <NUM> in six degrees of freedom. One or more of reference sensors <NUM> are attached to the chest of the patient. The six degrees of freedom coordinates of reference sensors <NUM> are sent to workstation <NUM>, which includes application <NUM> where sensors <NUM> are used to calculate a patient coordinate frame of reference.

In practice, a clinician may use the catheter guide assemblies <NUM>, <NUM> to navigate the EWC <NUM> using the LG <NUM> to reach the desired surgical site or an exit location from the luminal network of the lungs (e.g. the airways). The desired surgical site may be the area within the body of the patient that is affected by a lesion. An exit location from the luminal network of the lungs may be an area within the body that is closest to a lesion such as bronchial wall nearest to the lesion. If lesions are within an area of the body where they are difficult to reach from within the luminal network of the lungs then the lesions may be reached by piercing the exit location. Once the exit location is reached, the LG <NUM> is removed and bronchial piercing catheter <NUM> is inserted into the EWC <NUM>. Bronchial piercing catheter <NUM> is then advanced forward to pierce the bronchial walls while tracking its proximity to the target. Once placed in proximity to the target, the EWC <NUM> is also advanced forward. Bronchial piercing catheter <NUM> can then be removed, and a biopsy tool <NUM> can be inserted into the EWC <NUM> and advanced to the target such as the lesion to be treated. The use of the bronchial piercing catheter <NUM> allows the navigation of the EWC <NUM> to a target outside the airways.

In some embodiments, the LG <NUM> is integrated with the bronchial piercing catheter <NUM> and the bronchial piercing catheter <NUM> may be locked inside the EWC <NUM> so the distal end of the bronchial piercing catheter <NUM> is positioned inside the distal end of the EWC <NUM>. Bronchial piercing catheter <NUM> (with the integrated LG <NUM>) is then navigated with the EWC <NUM> to a desired exit location within the luminal network of the lungs. Once the exit location is reached, the bronchial piercing catheter <NUM> is advanced forward and locked relative to the EWC <NUM> in a second position in which the distal end of the bronchial piercing catheter <NUM> is just beyond the distal end of the EWC <NUM>. The bronchial piercing catheter <NUM> and the EWC <NUM> are then advanced forward to pierce the bronchial walls while tracking its proximity to the target. Using a sensor integrated with a bronchial piercing catheter eliminates the step of removing the LG <NUM> in order to place the bronchial piercing catheter <NUM> through the EWC <NUM>.

Of course, those of skill in the art will recognize that a blunt tipped dissector, or other tissue expander, including inflatable tissue expanders could be utilized in combination with the EWC <NUM> and the bronchial piercing catheter <NUM>, without departing from the scope of the present disclosure. For a more detailed description of the bronchial piercing catheter <NUM> reference is made to commonly-owned <CIT>.

If lesions are within an area of the body where they can be reached from the luminal network of the lungs then a biopsy tool, such as biopsy tool <NUM> may be used. Biopsy tool <NUM> may be inserted into the catheter guide assemblies <NUM>, <NUM> following navigation to a target and removal of the LG <NUM>. The biopsy tool <NUM> is used to collect one or more tissue sample from the target tissue. The biopsy tool <NUM> may be further configured for use in conjunction with tracking system <NUM> to facilitate navigation of biopsy tool <NUM> to the target tissue, tracking of a location of biopsy tool <NUM> as it is manipulated relative to the target tissue to obtain the tissue sample, and/or marking the location where the tissue sample was obtained. During navigation, EM sensor <NUM>, in conjunction with tracking system <NUM>, enables tracking of EM sensor <NUM> and/or biopsy tool <NUM> as EM sensor <NUM> or biopsy tool <NUM> is advanced through the patient's airways.

A variety of useable biopsy tools are described in <CIT> and <CIT> and <CIT>.

During procedure planning, workstation <NUM> utilizes computed tomographic (CT) image data for generating and viewing a three-dimensional model ("3D model") of the patient's airways, enables the identification of target tissue on the 3D model (automatically, semiautomatically or manually), and allows for the selection of a pathway through the patient's airways to the target tissue. More specifically, the CT scans are processed and assembled into a 3D volume, which is then utilized to generate the 3D model of the patient's airways. The 3D model may be presented on a display monitor <NUM> associated with workstation <NUM>, or in any other suitable fashion. Using workstation <NUM>, various slices of the 3D volume and views of the 3D model may be presented and/or may be manipulated by a clinician to facilitate identification of a target and selection of a suitable pathway through the patient's airways to access the target. The 3D model may also show marks of the locations where previous biopsies were performed, including the dates, times, and other identifying information regarding the tissue samples obtained. These marks may also be selected as targets to which a pathway can be planned. Once selected, the pathway is saved for use during the navigation procedure. An example of a suitable pathway planning system and method is described in <CIT>; <CIT>; and <CIT>, all entitled PATHWAY PLANNING SYSTEM AND METHOD, filed on March <NUM>, <NUM>.

Turning now to <FIG>, there is shown an enlarged view of a portion of EWC <NUM> connected to valve <NUM>, in accordance with aspects of the present disclosure, and a portion of a medical instrument <NUM>. Medical instrument <NUM> may be part of an ablation catheter, in which case medical instrument <NUM> is referred to herein as an ablation probe. Medical instrument <NUM> may be configured to be received within EWC <NUM>. Medical instrument <NUM> may extend through an entire length of the EWC <NUM> and into bronchoscope <NUM>. In some embodiments, medical instrument19 may include a microwave antenna (not shown). Examples of microwave antenna construction may be found in commonly assigned <CIT> entitled "Microwave Energy-Device and System," and<CIT> entitled "Microwave Ablation Catheter and Method of Utilizing Same". As depicted in <FIG>, valve <NUM> may be connected to EWC <NUM> perpendicularly.

After navigating the EWC <NUM> proximate the lesion it may be desirable to secure the EWC within the airways of the patient. In accordance with one embodiment of the present disclosure, this may be done by applying a vacuum to valve <NUM>, as will be described in greater specificity below with respect to treatment. The application of a vacuum to the EWC removes some of the air within the luminal network and can cause the luminal network to collapse onto the EWC, at least in the area proximate an opening operably connected to the valve <NUM>. This collapsing or apposition allows for the tissue of the luminal network itself to secure the orientation of the EWC <NUM>. This secured orientation can be verified using imaging techniques including ultrasound and fluoroscopy. Once confirmed the clinician can take the biopsy with confidence that the EWC is secured relative to the target and will acquire the desired tissue sample.

After a biopsy, in facilities utilizing Rapid Onsite Evaluation or (ROSE) the sample is analyzed for evidence of cancer or other diseases. Alternatively, following traditional evaluation techniques, if the sample is cancerous it may be desirable to treat the affected tissue. Treatment requires re-navigation of the EWC <NUM> to the target and insertion of a medical instrument <NUM> for treatment, such as a microwave ablation catheter through the EWC <NUM> and into the lesion or near the lesion to ablate the lesion. To ensure medical instrument <NUM> reaches the target tissue, bronchial piercing catheter <NUM> may first be inserted into a desired location in the target tissue (e.g. a tumor or mass), and then the EWC <NUM> may be advanced over the top of the bronchial piercing catheter <NUM> to secure the EWC <NUM> in the target tissue. The bronchial piercing catheter <NUM> is then removed and the medical instrument <NUM> can be navigated to the target tissue through the EWC <NUM>. In some embodiments the EWC <NUM> may have to be retracted after placement of the microwave ablation catheter to enable operation of the ablation catheter.

As described above, lesions may be partially filled with air, and puncturing a lesion or performing a biopsy of the lesion may result in the medical instrument used to the lesion to be surrounded by air. In some embodiments, a tissue-to-tool interface between energy source, medical instrument <NUM>, and target tissue, such as tissue of the target lesion, providing a consistent environment for energy delivery may be created suctioning air surrounding the energy source, medical instrument <NUM>. The air may be suctioned out of the luminal network by application of suction to valve <NUM>. <FIG> illustrates the flow of air <NUM> away from distal end of EWC <NUM> and through valve <NUM>. As described above, a vacuum source (not shown) may be connected to valve <NUM> to suction some or all of the air surrounding the EWC <NUM> or medical instrument <NUM>. The vacuum source may include, but not limited to, a syringe or a pump.

In some embodiments, a tissue-to-tool interface between medical instrument <NUM> and target tissue may be created by injecting a fluid into valve <NUM>. The injected fluid may provide a more consistent environment for energy delivery by a medical instrument <NUM> such as a microwave ablation catheter. The flow of fluid injected into valve <NUM> is depicted in <FIG> as flow <NUM>. The fluid injected into valve <NUM> may be any conductive fluid including, but not limited to, saline. In some embodiments, valve <NUM> may be a one-way valve. One-way valve <NUM> may include a duckbill seal. The duckbill seal may be configured with two states, a biased state and an unbiased state. In the biased state, fluid is allowed to pass through the duckbill, valve <NUM>, towards the distal end of medical instrument <NUM>. The biased state may also be referred to herein as when the duckbill is in an open state. In the unbiased state, no fluid passes through the duckbill or valve <NUM>.

The tissue-to-tool interface described in combination with isolation of the medical instrument <NUM> and the target tissue from other areas of the luminal network increases efficiency in delivery of energy, such as microwave energy. In embodiments employing suction, the tissue-to-tool interface created by the apposition of the tool and the target tissue improves delivery of therapeutic substances to the target tissue, and can eliminate or reduce leakage of therapeutic substance away from the target area. Additionally, the apposition of the tool with the target tissue allows for improved delivery of energy (e.g., microwave energy) and sonic waves (e.g., ultrasound waves) by eliminating nonconductive interfaces between the tool and the target tissue. Similarly, isolation and injection of a fluid into the luminal network homogenizes the environment through which energy (e.g., microwave or ultrasound) must travel and improves the transfer of energy for better treatment and imaging.

As depicted in <FIG>, air flow <NUM> and fluid flow <NUM> flows while medical instrument <NUM> is positioned within EWC <NUM>. As a result, air flow <NUM> and fluid flow <NUM> flows in a space defined between medical instrument <NUM> and EWC <NUM>. Additional details of a flow in a space provided between an energy source and an EWC is provided herein in <FIG>.

Turning now to <FIG>, there is shown a cross-sectional view of EWC <NUM> that illustrates a space between medical instrument <NUM> and EWC <NUM>. The cross-sectional view <NUM> illustrates the EWC <NUM> and medical instrument <NUM> positioned within the EWC <NUM>. Space <NUM> is annularly defined between the EWC <NUM> and the medical instrument <NUM>. Flow A, which may be air flow <NUM> or fluid flow <NUM> flows within space <NUM>. Flow A travels along the length of bronchoscope <NUM>, via the EWC <NUM>. Flow A does not directly contact the bronchoscope <NUM>, but stays within EWC <NUM> until it exits EWC <NUM>. Flow A flows circumferentially around the ablation medical instrument <NUM> within the annular space <NUM>. In this way, EWC <NUM> (or primary channel) achieves the dual purpose of allowing a clinician to simultaneously use/manipulate a surgical instrument and create a tool-to-tissue interface between instrument and tissue through EWC <NUM>. Though shown here as ending at the distal end of the EWC <NUM> the annular space <NUM> may also terminate in one or more openings formed on the side of the EWC <NUM>. As such, the apposition of tissue to the EWC <NUM> and medical instrument <NUM> may be enhanced and promote greater sealing characteristics.

Turning now to <FIG> there is shown an enlarged view of a portion of an extended working channel <NUM> comprising a port or opening <NUM> and balloons <NUM>, <NUM> within an airway of a patient. <FIG> depicts an airway <NUM>, an alveolus <NUM> that branches off airway <NUM>, and a lesion <NUM> that is formed within alveolus <NUM>. EWC <NUM> is inserted into airway <NUM> and a proximal balloon <NUM> extends from EWC <NUM>. Balloon <NUM> may extend laterally from EWC <NUM>, as depicted in <FIG>, and seal the portion of the airway <NUM> proximal of the distal end of EWC <NUM>. Medical instrument <NUM> extends from the distal end of EWC <NUM>. Medical instrument <NUM>, as described above, may be a microwave ablation catheter. In some embodiments, medical instrument <NUM> may be a catheter configured to deliver therapeutic substance, such as a chemotherapy substance, to the target tissue.

In at least one embodiment a balloon catheter <NUM> extends from EWC <NUM> and includes balloon <NUM> at the distal end of catheter <NUM>. Fluid line <NUM> is in fluid communication with balloon <NUM>. In some embodiments, fluid line <NUM> may be a dual fluid line that includes a first fluid line <NUM> and a second fluid line <NUM>. In some embodiments, balloon <NUM> may be expanded by application of fluid through fluid line <NUM>. Fluid may be applied to the balloon <NUM> through a fluid line attached to the balloon, such as fluid line <NUM>. Fluid line <NUM> passes through distal balloon <NUM> and fluidly connects a portion of airway <NUM> with atmosphere or a ventilation device (not shown) that permits lung comprising airway <NUM> to receive and expel air. Balloons <NUM> and <NUM> create an area in airway <NUM> that is effectively sealed from the atmosphere.

Port <NUM> located on the distal portion of EWC <NUM> and is in fluid communication through EWC <NUM> to a vacuum source, such as a pump or syringe (not shown). A tissue-to-tool interface between medical instrument <NUM> and lesion <NUM>, providing a consistent environment or zone may be created by suctioning air surrounding the medical instrument <NUM>. The vacuum generated by vacuum source is sufficient to place medical instrument <NUM> in apposition with tissue of lesion <NUM>, but not necessarily enough to cause atelectasis or collapse of alveolus <NUM>.

In embodiments where medical instrument <NUM> is an energy delivery probe, such as a microwave ablation probe, the tissue-to-tool interface created between medical instrument <NUM> and lesion <NUM> improves delivery of energy to the lesion <NUM> because the non-conductive interface, (i.e., the air between medical instrument19 and lesion <NUM>), is substantially eliminated. In embodiments where medical instrument <NUM> delivers a therapeutic substance the tissue-to-tool interface created between medical instrument <NUM> and lesion <NUM> improves delivery of the therapeutic substance to lesion <NUM> by eliminating leakage of the therapeutic substance beyond the portion of the airway <NUM> isolated by balloons <NUM> and <NUM>, thus limiting the therapeutic substance to those areas where they will be most effective, namely alveolus <NUM> and a small section of airway <NUM>.

Turning now to <FIG>, there is shown an enlarged view of a medical instrument 700a for percutaneously accessing and treating a target tissue. Medical instrument 700a includes a handle <NUM> coupled with an ablation probe <NUM>. In some embodiments, ablation probe <NUM> extends from handle <NUM>. Ablation probe <NUM> includes a microwave ablation antenna (not shown) that is used to ablate tissue. Handle <NUM> includes a housing unit (not shown) configured to house catheter <NUM>. Catheter <NUM> is optionally configured to extend out from the housing unit within handle <NUM> and retract into the housing unit within handle <NUM>. Catheter <NUM> defines a lumen 701a and ablation probe <NUM> is located within lumen 701a.

A control unit, such as wheel <NUM>, is configured to control the extension and retraction of catheter <NUM> such that rotating wheel <NUM> away from the clinician holding handle <NUM> or in the direction X' extends catheter <NUM> by moving catheter <NUM> in the direction X' and rotating wheel <NUM> towards the clinician holding handle <NUM> or in the direction X retracts catheter <NUM> into the housing unit of handle <NUM> by moving catheter <NUM> in the direction X. In some embodiments, the control unit may be a slider, where sliding the slider away from the clinician holding handle <NUM> or in the direction X' extends the catheter <NUM> and sliding the slider towards the clinician holding handle <NUM> or in the direction X retracts the catheter <NUM>. Alternatively the catheter <NUM> may be formed of a trocar or other component inserted into the patient proximate the target tissue through which the ablation probe <NUM> is inserted in accordance with embodiments of the present disclosure.

Medical instrument 700a may include one or more markers, such as markers 710a, 710b, to help guide a clinician in determining how far to extend the catheter in order to most efficiently create the tissue-to-tool interface, described herein, between the ablation probe <NUM> and a target tissue, such as a lesion. Each of the markers indicates a different length of extension and based on how deep ablation probe <NUM> is inserted into a patient, a marker may more effectively create the desired tissue-to-tool interface than other markers.

Catheter <NUM>, via port 705a and tube <NUM>, is in fluid communication with a vacuum source (not shown) or a liquid source (not shown). Port 705a is in fluid communication with lumen 701a of the catheter <NUM>. Tube <NUM> is configured and coupled with catheter <NUM>, via port 705a, such that one end of tube <NUM> is attached to an end of lumen 701a of catheter <NUM> that is proximal to the clinician, via port 705a, and the other end of tube <NUM> is coupled with the vacuum or liquid source. As described above, the vacuum source described herein includes, but is not limited to, a pump or a syringe. The vacuum source generates a vacuum by suctioning air, through tube <NUM>, via lumen 701a, around ablation probe <NUM>. The application of vacuum is sufficient to place ablation probe <NUM> in apposition with the target tissue, thus, creating a consistent zone around ablation probe <NUM>, but not enough to cause atelectasis. Also as described above, a liquid source, as described herein, provides a fluid such as saline. The fluid from the liquid source helps create a consistent zone around ablation probe <NUM> by injecting fluid from the liquid source through tube <NUM> and onto at least a portion of the target tissue, via lumen 701a.

Turning now to <FIG>, there is shown a medical instrument 700a with the catheter <NUM> extended to marker 710a and in a fluid communication with a vacuum source (not shown). As depicted by airflow <NUM>, air is suctioned away from target tissue through lumen 701a, which is in fluid communication with tube <NUM>, via port 705a. As described above, suctioning sufficient amount of air away from target tissue places the target tissue in apposition with the target tissue, which creates a more consistent zone around ablation probe <NUM>. <FIG> illustrates medical instrument 700a with the catheter <NUM> in a fluid communication with a liquid source, which provides a fluid, such as saline. Fluid flow <NUM> depicts the flow of fluid, for example saline, onto the target tissue, through lumen 701a, which is in fluid communication with tube <NUM>, via port 705a, in order to form a consistent zone around ablation probe <NUM>. Thus, a tissue-to-tool interface is created while accessing and treating target tissue percutaneously.

Turning now to <FIG>, there is shown an embodiment of a catheter that may be attached to the medical instrument 700a instead of being housed in medical instrument 700a. Catheter <NUM> defines a lumen 706a and includes a port <NUM>, which is configured to be in fluid communication with a vacuum source or a liquid source. Port <NUM> is in fluid communication with lumen 706a of catheter <NUM>. While a single catheter <NUM> is depicted in <FIG>, a plurality of catheters <NUM>, each of a different length may be used and selection of a particular catheter <NUM> may be based on how deep ablation probe <NUM> is inserted into a patient. Catheter <NUM> may be attached to the medical instrument 700a by fastening it into medical instrument 700a using opening <NUM> on the handle <NUM>, as depicted in <FIG>.

Turning now to <FIG>, there is shown a cross-sectional view of medical instrument 700a without attachment of catheter <NUM> to medical instrument 700a. The end of catheter <NUM> that is proximal to port <NUM> may be configured with an external thread profile (not shown) to allow catheter <NUM> to be fastened into opening <NUM> on the handle <NUM>. Opening <NUM> may be configured with an internal thread profile (not shown) to accept catheter <NUM>. Catheter <NUM> may be attached to the medical instrument 700a by fastening it into medical instrument 700a using opening <NUM>. Other connection mechanisms including press fittings, suction fittings, and the like are within the scope of the present disclosure. Once fastened into opening <NUM>, catheter <NUM> surrounds ablation probe <NUM> as illustrated in <FIG> illustrates port <NUM> being in fluid communication with a vacuum source (not shown) via tube <NUM>. The tissue-to-tool interface, described above, is created by suctioning air away from target tissue through lumen 706a, using the vacuum source in fluid communication with port <NUM> via tube <NUM>, as depicted by air flow <NUM>. Thus, placing ablation probe <NUM> in apposition with target tissue and forming a consistent zone around the ablation probe. <FIG> illustrates port <NUM> being in fluid communication with a liquid source, which provides fluid, such as saline. The fluid may be injected onto at least a portion of target tissue using tube <NUM> and lumen 706a of catheter <NUM>, as depicted by liquid flow <NUM>. Thus, forming a consistent zone around ablation probe <NUM>.

The embodiments disclosed herein are examples of the disclosure and may be embodied in various forms. For instance, although certain embodiments herein are described as separate embodiments, each of the embodiments herein may be combined with one or more of the other embodiments herein. Specific structural and functional details disclosed herein are not to be interpreted as limiting, but as a basis for the claims and as a representative basis for teaching one skilled in the art to variously employ the present disclosure in virtually any appropriately detailed structure. Like reference numerals may refer to similar or identical elements throughout the description of the figures.

The phrases "in an embodiment," "in embodiments," "in some embodiments," or "in other embodiments" may each refer to one or more of the same or different embodiments in accordance with the present disclosure. A phrase in the form "A or B" means "(A), (B), or (A and B). " A phrase in the form "at least one of A, B, or C" means "(A); (B); (C); (A and B); (A and C); (B and C); or (A, B, and C).

Claim 1:
A surgical apparatus (700a) for percutaneously accessing and treating a target tissue, the apparatus comprising an ablation probe (<NUM>), a catheter (<NUM>) and a handle (<NUM>) coupled with the ablation probe (<NUM>) and configured to receive the catheter (<NUM>), the catheter having a proximal end and a distal end and defining a lumen (701a) for surrounding the ablation probe (<NUM>), the proximal end of the catheter having a port (705a) and a tube (<NUM>) in fluid communication with the lumen of the catheter for coupling to a vacuum source or a liquid source, whereby coupling to the vacuum source enables air to be suctioned through the tube (<NUM>) from the distal end to the proximal end of the lumen (701a) around the ablation probe (<NUM>) to place the probe in apposition with target tissue, and whereby coupling to the liquid source supplies fluid from the proximal end to the distal end of the lumen (701a) around the ablation probe onto at least a portion of the target tissue,
characterised in that:
the catheter (<NUM>) is configured to extend out of, and retract into, a housing unit within the handle and a control unit comprising a rotating wheel (<NUM>) or slider is configured to control the extension and retraction of the catheter (<NUM>).