MULTIPLE SENSOR CATHETER ASSEMBLY

An ultrasound imaging device includes a substrate, an ultrasound transducer array mounted on the substrate, a pressure sensor mounted on the substrate, and an integrated circuit mounted on the substrate and operatively connected to the ultrasound transducer array and to the pressure sensor. The integrated circuit includes a memory that is programmable to store a transmit-receive sequence and operational codes to optimize a sub-aperture of the ultrasound transducer array to support an ultrasound scanning modality that is selected for the ultrasound imaging device.

BACKGROUND

Catheters and endoscopes are diagnostic devices that are used to guide medical interventions such as percutaneous coronary interventions and pulmonary lymph node biopsies. Typical design constraints for catheters and endoscopes include device size for anatomical access, and thermal performance for patient safety. Further, there are competing clinical user needs that generally add complexity to these devices such as preference for multiple sensors. For example, use of multiple sensors can improve workflow and performance by reducing the quantity of device exchanges.

It would be advantageous for diagnostic catheter and endoscope devices to integrate more complex sensors, including ultrasound imaging arrays and physiological sensors. It would be further advantageous for these devices to reduce heat generation for patient safety and reduce the number of wires for size constraints. It would be still further advantageous for a flexible solution to enable use for multiple clinical applications.

SUMMARY

The present disclosure relates generally to medical devices used for imaging and sensing within a lumen or cavity. In one possible configuration, catheters and endoscopes are described for ultrasound imaging and physiological sensing. Various aspects are described in this disclosure, which include, but are not limited to, the following aspects.

In one aspect, an ultrasound imaging device comprises an ultrasound transducer array having a plurality of transducer array elements; and an integrated circuit operatively connected to the ultrasound transducer array, the integrated circuit including a memory programmable to store a transmit-receive sequence and operational codes to optimize a sub-aperture of the ultrasound transducer array to support an ultrasound scanning modality that is selected for the ultrasound imaging device, the sub-aperture having a subset of transducer array elements less than the plurality of transducer array elements.

Another aspect relates to an imaging assembly for an ultrasound imaging device. The imaging assembly comprises an ultrasound transducer array; and a controller operatively connected to the ultrasound transducer array, the controller having a memory that is programmable to store instructions which, when executed by the controller, cause the controller to: operate in an initialization mode that includes receiving a transmit-receive sequence and operational codes and storing them in the memory, the operational codes configuring the imaging assembly to perform an ultrasound scanning modality selected from a group consisting of a cylindrical ultrasound scanning modality, a side ultrasound scanning modality, and a forward looking 3D ultrasound scanning modality; and operate in a mission mode that includes executing the transmit-receive sequence to optimize performance of the selected ultrasound scanning modality by the ultrasound transducer array

Another aspect relates to a method of performing ultrasound imaging using a programmable imaging assembly. The method comprising: selecting an ultrasound scanning modality; assembling the imaging assembly for the selected ultrasound scanning modality; uploading a transmit-receive sequence and opcodes to a memory of the imaging assembly, the transmit-receive sequence and opcodes configuring the imaging assembly to perform the selected ultrasound scanning modality; acquiring ultrasound signal data from the imaging assembly; and processing the acquire ultrasound signal data for displaying ultrasound images in accordance with the selected ultrasound scanning modality on a display device.

DETAILED DESCRIPTION

The embodiments described herein relate to catheters, needles, cannulas, endoscopes, and the like with multiple sensors to guide the treatment of patients. In some applications, a catheter is designed for use in a coronary artery. In further applications, an endoscope is designed for use in bronchi or airways in the lungs. Additionally, the embodiments described herein are not limited to the above-referenced applications.

FIG. 1is an illustrative example of a catheter laboratory10that includes a patient table20and an X-ray C-arm30for guiding diagnostic and therapeutic cardiovascular interventions of a patient40. The catheter laboratory10may also include an intravascular ultrasound (IVUS) imaging and pressure sensing console90and catheter100.

The IVUS imaging and pressure sensing console90may house various operating components that control the operation of the catheter100, send signals to or receive signals from catheter100, or store data generated by or used with the catheter100. In some examples, the IVUS imaging and pressure sensing console90also includes a user interface that enables a physician to interact with the catheter100and/or display information generated by the catheter. The broken lines inFIG. 1represent portions of catheter100within the patient40.

FIG. 2illustrates an ultrasound imaging system200. As shown inFIG. 2, the ultrasound imaging system200includes an imaging assembly202, one or more wires204, a patient interface module206, an imaging engine208, and a display computer or tablet210. In certain embodiments, the imaging assembly202is the imaging assembly300that will be described in more detail below with reference toFIGS. 5-9. In alternative embodiments, the imaging assembly202is the imaging assembly1300that will be described in more detail below with reference toFIGS. 11-14.

As will be described in more detail, the imaging assembly202includes at least an ultrasound transducer array (see, for example, the ultrasound transducer array320inFIG. 5and the ultrasound transducer array1320inFIG. 11). The ultrasound transducer array converts electrical signals into ultrasound signals, and converts reflected ultrasound signals into electrical signals that can be used to image a target. For example, by measuring the time between sending an ultrasound signal and receiving an echo, the distance of an object can be calculated. In certain embodiments, the ultrasound transducer array is a micro-electro-mechanical system (MEMS) transducer. In certain embodiments, the imaging assembly202can also include additional sensors that can detect and receive physiological data such as the pressure sensor330shown inFIG. 5.

In the example ofFIG. 2, the imaging assembly202is operatively connected to the patient interface module206by the one or more wires204that can be inserted through a catheter or needle. As will be described in more detail, the patient interface module206uploads a transmit-receive sequence and operational codes (opcodes) to a memory of the imaging assembly202such that the imaging assembly202is programmable to operate a variety of different types of ultrasound scanning modalities.

The patient interface module206is operatively connected to the imaging engine208. The patient interface module206can relay ultrasound signal data from the imaging assembly202to the imaging engine208, and the imaging engine208can process the ultrasound signal data to produce real-time ultrasound images. The patient interface module206can relay additional data from the imaging assembly202to the imaging engine208such as physiological data and tracking data that can be processed by the imaging engine208for display along with the real-time ultrasound image.

The patient interface module206can relay instructions from the imaging engine208to the imaging assembly202during performance of an image capture sequence in real-time. For example, the imaging engine208can vary the gain provided by a low-noise amplifier (LNA) that is included on the imaging assembly202to reduce power consumption on the imaging assembly202, and thereby reduce the heat generated by the imaging assembly202during the image capture sequence.

Additionally, the imaging engine208can vary in-real-time the transmit repetition rate or period of the transmit-receive sequences performed by the imaging assembly202during the image capture sequence to extend or contract the field of view or increase or decrease the frame rate. Advantageously, varying in-real-time the transmit-receive sequences performed by the imaging assembly202can help to increase the frame rate of the ultrasound images when desirable for a clinical application, or alternatively increase the image quality and depth of the ultrasound images when desirable.

Also, the imaging engine208can vary in real-time a transmit voltage and frequency directed to the ultrasound transducer array of the imaging assembly202during the image capture sequence. Furthermore, the imaging engine208can vary the length of the receive window, which varies the time the low-noise amplifier (LNA) is powered on and the amount of heat generated by imaging assembly202. The imaging engine208can further adjust the timing and operation of a transmit/receive switch406(seeFIG. 6) on the imaging assembly202to reduce near-field artifacts or increase near-filed response.

Additionally, the imaging engine208can receive a cyclic redundancy check signal from the imaging assembly202that can identify whether there was an error in uploading the transmit-receive sequence and opcodes to the programmable memory of the imaging assembly202. These concepts will be described in more detail below.

As further shown inFIG. 2, the display computer or tablet210is operatively connected to the imaging engine208by one or more wired, fiber optic, or wireless connections, or combinations thereof. The imaging engine208provides the real-time ultrasound image, and physiological and tracking data for display and analysis on the display computer or tablet210. In certain embodiments, the display computer or tablet210is portable device such as a tablet computer or smartphone device.

FIG. 3shows ultrasound scanning modalities250that the imaging assembly202can be assembled and programmed to perform. The ultrasound scanning modalities250can include a cylindrical ultrasound scanning modality252, a side ultrasound scanning modality254, or a forward looking 3D ultrasound scanning modality256.

The imaging assembly202is assembled and programmed to perform an ultrasound scanning modalities250based on a desired clinical application. For example, the imaging assembly202can be assembled and programmed to perform the cylindrical ultrasound scanning modality252when it is desirable to scan inside a lumen such as an artery. The imaging assembly202can be assembled and programmed to perform the side ultrasound scanning modality254when it is desirable to scan a surface such as a wall of the heart cavity. The imaging assembly202can be assembled and programmed to perform the forward looking 3D ultrasound scanning modality256when it is desirable to scan a closed off area that the imaging assembly202is not able to pass through.

Initially, the imaging assembly202can be assembled to perform one of the example ultrasound scanning modalities250, and thereafter the patient interface module206can be used to upload a transmit-receive sequence and opcodes to a memory of the imaging assembly202to program the imaging assembly202for performing the ultrasound scanning modality based on a clinical application.

As an illustrative example, the imaging assembly202can be assembled to perform the cylindrical ultrasound scanning modality252, and the transmit-receive sequence and opcodes can optimize the performance of the cylindrical ultrasound scanning modality252by the imaging assembly202. For example, the transmit-receive sequence and opcodes can optimize a sub-aperture size of an ultrasound transducer array on the imaging assembly202based on a clinical application. A synthetic aperture ultrasound imaging system that can adjust a sub-aperture size of an ultrasound transducer array is described in U.S. patent application No. 62/989,268 filed on Mar. 13, 2020, which is hereby incorporated by reference in its entirety.

As a further example, a sub-aperture for performing the cylindrical ultrasound scanning modality252can be optimized to increase the number of receive elements within the sub-aperture to improve quality of the ultrasound images when desirable. Alternatively, the sub-aperture for performing the cylindrical ultrasound scanning modality252can be optimized to decrease the number of receive elements within the sub-aperture to increase the frame rate of the ultrasound images when desirable.

As another illustrative example, the sub-aperture can be decreased for performing the cylindrical ultrasound scanning modality252when an increased frame rate is desirable such as when imaging leaflet motion inside a valve of a heart. Alternatively, the sub-aperture can be increased when improved image quality is desirable. The programmable sub-aperture for performing the cylindrical ultrasound scanning modality252will be described in more detail below with reference toFIGS. 17-20.

FIG. 4is a partial sectional view of a distal end of an example IVUS imaging and the catheter100. For illustrative purposes only, some embodiments of the catheter100are appropriate for intracoronary catheters. However, the described embodiments of the catheter100are not limited to intracoronary catheters, and accordingly may be used in other types of catheters, endoscopes, and similar devices.

In the example embodiment shown, the catheter100includes a distal tip110, a distal shaft120, a sensor assembly section130, and a cable harness132. The distal tip110may include a tapered, elongated tube112having at least one layer. The distal tip110further includes a guide wire lumen114and a side port116. In certain embodiments, the catheter100and sensor assembly section130are disposable after a single use.

In certain embodiments, the distal tip110has an inner diameter suitable for an 0.014 inch guide wire. For example, the distal tip110can have an inner diameter of about 0.0165 inches. The distal tip wall may taper from a proximal outer diameter between about 0.003 inches and about 0.009 inches to a distal outer diameter between about 0.001 inches and about 0.003 inches. The distal tip110can have a length suitable for tracking along the guide wire. For example, in some embodiments, the distal tip110can have a length between about 5 mm and about 30 mm.

In certain embodiments, the distal tip110is made from Pebax material. The distal tip110may also include an inner liner made of high-density polyethylene (HDPE) or polytetrafluoroethylene (PTFE) to reduce friction between the distal tip and a guide wire (not shown). The side port116enables fluid communication between a blood-filled coronary artery and at least a portion of the sensor assembly section130. A radiopaque marker band (not shown) composed or platinum or iridium may be included in the distal tip110to aid visualization of the catheter in x-ray angiographic images.

The distal tip110is bonded to the distal shaft120. The distal shaft120can include a proximal end, a distal end, and a length extending between the proximal and distal ends. The distal shaft120can include any suitable material capable of having different flexural moduli along the shaft's length. In some embodiments, the distal shaft120includes a hypotube. The hypotube may be a spiral-cut, stainless steel hypotube.

The distal shaft120further includes a lumen122. The distal shaft120may further include a polymer jacket and a liner to seal the lumen122from the external blood-filled coronary artery. The distal shaft120has an outer diameter that is sufficiently small to minimize effects on coronary artery blood flow when the catheter100is inside a coronary artery. The outer diameter of the distal shaft120is preferably 0.018 inches or smaller. The inner diameter of the distal shaft may be 0.016 inches or smaller.

FIG. 5is a top view of an example imaging assembly300before forming.FIGS. 8 and 9, which will be described in more detail below, show the imaging assembly300after forming. In certain embodiments, the imaging assembly300can be included as a part of the sensor assembly section130of the catheter100shown inFIG. 4. In certain embodiments, the imaging assembly300is assembled and configured to perform the cylindrical ultrasound scanning modality252shown inFIG. 3.

The pre-formed imaging assembly300includes a flexible substrate310, an ultrasound transducer array320, a pressure sensor330, and mixed-signal integrated circuits (ICs)340,342,344,346. The pre-formed imaging assembly300further includes circuit traces350, and a plurality of capacitors such as capacitors360,362,364,366,368,370,372. This chip-on-flex design provides technical advantages including geometrical and mechanical flexibility that is important for catheter applications.

The flexible substrate310is a laminated structure that includes a coverlay, at least one electrical insulating layer, electrically conductive features, and adhesives. The coverlay and at least one insulating layer can be made of polyimide. A polyimide layer may be as thin as approximately 12 μm. The electrically conductive features, such as circuit traces350, can be etched from copper foils as thin as about 10 μm thick, or can be vapor deposited copper of about 2-4 μm thick, vapor deposited nickel of about 2-4 μm thick, or vapor deposited gold of about 0.5 μm thick. The flexible substrate310includes electrical contacts such as pads for die (chip) attachment of components for the mixed-signal ICs340,342,344,346.

The ultrasound transducer array320includes an array of 64 elements wherein each element includes a piezoelectric layer such as lead zirconate titanate (PZT). The ultrasound transducer array320can be formed by bonding the piezoelectric layer to the flexible substrate310. In some embodiments, the piezoelectric layer may have a resonant frequency between about 10 MHz and about 30 MHz. In certain embodiments, the piezoelectric layer may have a resonant frequency of about 20 MHz. The dimensions of the piezoelectric layer are approximately 3.2 mm by 1 mm by 0.09 mm. The piezoelectric layer can be diced to form 64 elements that are approximately 50 μm wide. The kerf width (or distance between elements) can be approximately 12 μm.

In some embodiments, the ultrasound transducer array320is a microelectromechanical system (MEMS) transducer that is fabricated using one or more types of semiconductor processes, with interconnecting traces such that the imaging assembly300does not include the flexible substrate310. Instead, one or more of the mixed-signal ICs340,342,344,346are bonded to the MEMS transducer, and thereby form a multi-chip module using a stacked die assembly approach.

In some embodiments the pressure sensor330is a piezoresistive pressure die that has dimensions of approximately 0.9 mm (length) by 0.33 mm (width) by 0.18 mm (height). The piezoresistive pressure die includes two piezo-resistors, or a half bridge of a Wheatstone bridge. In some embodiments, the bridge resistance is between about 2000Ω and about 3500Ω. In certain embodiments, the bridge resistance is about 3200Ω. Two matched bridge additional 3000Ω resistors, which are internal components of mixed signal ICs340,342,344,346, are connected to the piezoresistive pressure die to complete the full-bridge configuration. In some embodiments, the pressure sensor330is powered by a voltage in a range of about 1 V to about 6 V. In certain embodiments, the pressure sensor330is powered by a voltage of approximately 3 V.

FIG. 6shows the mixed-signal IC340in greater detail. While the mixed-signal IC340is shown and described as being used in the imaging assembly300which is assembled and configured to perform the cylindrical ultrasound scanning modality252, it is contemplated that the mixed-signal IC340can be used in additional types of imaging assemblies such as ones that are assembled and configured to perform the side ultrasound scanning modality254, or the forward looking 3D ultrasound scanning modality256.

As shown inFIG. 6, the mixed-signal IC340includes a set of transmitters402, a multiplexer404, a transmit/receive switch406, analog circuitry408, a controller410, and input/output buffers412. In some embodiments, the multiplexer404is a 16:1 receiver multiplexer that multiplexes 16 transducer array elements.

The mixed-signal IC340includes interfaces for power and data pins420to the patient interface module206which is programmed and powered by the imaging engine208(seeFIG. 2). The mixed-signal IC340also includes board-level strapping pins422, connectivity pins424to the other mixed-signal ICs342,344,346, communication pins426to the other mixed-signal ICs342,344,346, capacitor pins428, a low-voltage power supply pin430, a set of transducer element pins432to the ultrasound transducer array320, and piezoresistive bridge pins434to the pressure sensor330.

The transmit/receive switch406is capacitively coupled to the analog circuitry408. The analog circuitry408includes a low-noise amplifier (LNA)409. The LNA409is configurable to provide gain to the ultrasonic signals received from the ultrasound transducer array320via the transducer element pins432. In certain examples, the LNA409is a receiver amplifier implemented on the mixed-signal IC340.

The analog circuitry408is configured to vary the voltage and current on the LNA409to reduce the power consumption on the mixed-signal IC340for certain applications of the imaging assembly300. For example, the gain and compression point on the LNA409can be varied to manage the power consumption of the LNA409. In certain embodiments, the gain on the LNA409can be varied to reduce power consumption on the mixed-signal IC340from about 3 V to about 2.7 V. Advantageously, reducing the power consumption of the LNA409can reduce the amount of heat generated by the mixed-signal IC340. Alternatively, increasing the gain on the LNA409(and thereby increasing the power consumption of the LNA409) can be advantageous in applications where additional amplification is beneficial and heat generation is not a concern. In certain embodiments, the gain (and power consumption) of the LNA409is managed by the controller410, which is programmed by an external host system such as the imaging engine208via the patient interface module206.

The controller410includes a counter411and a memory415that is programmable. The memory415is programmable to store a transmit-receive sequence and operational codes (opcodes) for execution by the controller410to complete an entire scan (frame) of image data. Once the imaging assembly300is assembled to perform a selected ultrasound scanning modality250such as the cylindrical ultrasound scanning modality252, side ultrasound scanning modality254, or forward looking 3D ultrasound scanning modality256(seeFIG. 3), the memory415enables the mixed-signal IC340to be configurable to support the selected ultrasound scanning modality250.

In certain embodiments, the memory415is a static random-access memory (SRAM) that can dynamically store the transmit-receive sequence and opcodes to configure the mixed-signal IC340to support the ultrasound scanning modality250selected for the assembled imaging assembly300such as the cylindrical ultrasound scanning modality252, side ultrasound scanning modality254, or forward looking 3D ultrasound scanning modality256.

The transmit-receive sequence and opcodes are uploaded to the memory415via the power and data pins420which are connectable to the patient interface module206ofFIG. 2. The transmit-receive sequence and opcodes can be configured to support a cylindrical array sequence or a linear array sequence by configuring the mixed-signal ICs340,342,344, and346, and by programming the SRAM. In some embodiments, the mixed-signal ICs340,342,344,346are each separately configured to electrically excite 16 elements of the 64-element ultrasound transducer array in a predetermined order.

The transmit-receive sequence may also include “no operation” events. The no-operation (no-op) opcode combined with the counter411can reduce the size of the memory415. The SRAM can have a storage of approximately 1024×10 bits for storing the transmit-receive sequence and opcodes. The no-op event can also disable each mixed-signal IC340,342,344,346(i.e., to stand by) for a set of clock cycles tracked by the counter411, which can further reduce the heat generated by the imaging assembly300.

The power and data pins420provide power signals for high-voltage supply, low-voltage supply, and ground. The power and data pins420further provide analog signals for a high-speed low-voltage differential signaling (LVDS) to transmit signals and differential or single ended receive signals for ultrasound and pressure output signals.

The power and data pins420still further provide a digital signal for an input clock signal. The board-level strapping pins422provide digital signals to identify which chip is “master” and which chips are “slaves.” The connectivity pins424provide pass-throughs for the power signals for high-voltage supply, low-voltage supply, ground, and for receive signals such as the ultrasound output signals.

The communication pins426provide a pass-through for the digital clock signal, a pass-through a digital transmit signal, and a cyclic redundancy check (CRC) signal419. The CRC signal419enables each mixed-signal IC to report events where the transmit-receive sequence and operational codes in SRAM is incorrect.

The CRC signal419is generated by an error checking circuit417that uses the DC bias of the differential signaling to perform an error check. For example, a pair of differential transmit signals can be biased by a voltage of a predetermined amount, and the error checking circuit417can pull one differential signal to zero to determine whether an error has occurred. Advantageously, the CRC signal419can report to an external host system, such as the patient interface module206ofFIG. 2, that there is an error without having to use a dedicated transmission line on the mixed-signal IC340or additional circuits within mixed-signal ICs340,342,344, and346to enable bi-directional communication over a single transmission line or wire.

The high-voltage supply provided from the power and data pins420can be varied to adjust the transmit voltage of transmitters XMTR1-XMTR16. For example, the high-voltage supply on the mixed-signal ICs340,342,344, and346can be increased to provide a more powerful transmission from the transmitters XMTR1-XMTR16, or can be decreased to provide a less powerful transmission from the transmitters XMTR1-XMTR16. In some embodiments, the high-voltage supply can be varied between about 8 V and about 20 V. In certain examples, the high-voltage supply can be set at about 15 V.

The low-voltage supply provided from the power and data pins420can also be varied during operation of the imaging assembly300. For example, the low-voltage supply can be decreased to reduce the power consumption of the LNA409. In some embodiments, the low-voltage supply can be varied between about 2.7 V and about 3 V. In certain embodiments, the low-voltage supply can be set at about 3 V.

The clock signal provided from the power and data pins420can also be varied during operation of the imaging assembly300. For example, the clock signal can be varied to increase or decrease the frequency of the transmit-receive sequences. In some embodiments, the clock signal can be varied between about 10 kHz and about 120 kHz. In certain embodiments, the clock signal operates can be set at about 54 kHz.

In the example embodiment illustrated in the figures, the set of transmitters402includes 16 transmitters that each connect to one of the transducer element pins432and an ultrasound transducer element of the ultrasound transducer array320. The programming of the mixed-signal ICs340,342,344, and346by the patient interface module206, causes the multiplexer404, transmit/receive switch406, analog circuitry408, and controller410to follow a predetermined sequence of transmit and receive events for the transducer array elements of the ultrasound transducer array320.

The transmit/receive switch406can be programmed to switch through three states to precisely control when, relative to the transmit event, the receiver is enabled to minimize near-field imaging artifacts, such as near-field artifacts. The first state enables the multiplexer404output, the second state places the transmitter402into a high impedance state, the third state releases a weak pulldown on the receiver output, which initiates the beginning of the receive window. In an example embodiment in which the imaging assembly300performs synthetic aperture imaging, the mixed-signal IC340transmits on a first transmitter XMTR1and is configured to receive sequentially on all 16 transducer elements. In some embodiments, the transmitter output is between about 8 V and about 20 V. In certain embodiments, the transmitter output is about 15 V.

The transmitter (e.g., XMTR1) may generate a series of monopolar pulses, such as a single pulse or a double pulse. In some embodiments, the pulse width is between about 10 ns and about 100 ns. In certain embodiments, the pulse width is about 20 ns. In some embodiments, the delay between double pulses is between about 15 ns and about 100 ns. In certain embodiments, the delay between double pulses is about 20 ns. The sequence is then repeated for the remaining transmitters (e.g., XMTR2to XMTR16).

The sequence may further include receiving signals from transducer elements connected to another mixed-signal IC. The size of the mixed-signal IC340is approximately 2.0 mm by 0.5 mm by 0.1 mm to enable use in small imaging and sensing catheters that are approximately 3 F (1 mm diameter) in size.

It can be advantageous for a minimally invasive image guidance device, such as a catheter or endoscope, to reduce the number of transmission lines, and thereby reduce the size of the device for insertion into a human body. However, a disadvantage is that normal organ motion, such as cardiac and respiratory movements, can result in undesirable motion artifacts in cases where a synthetic imaging sequence may not be sufficiently short in duration to temporally resolve the motion.

The mixed-signal IC340can overcome these challenges by being programmable to increase or decrease a sub-aperture size of the ultrasound transducer array320as needed. By enabling the mixed-signal IC340to be programmable to increase or decrease the sub-aperture size, the acquisition time and motion artifacts can be minimized, while also minimizing the size of the catheter or endoscope device.

Additionally, the mixed-signal IC340can overcome the above-identified challenges either by being grouped together with other mixed-signal ICs to share a single receive channel such as for cylindrical imaging and small sub-apertures (less than ¼ of the total number of transducer array elements of the ultrasound transducer array320), or by separately interfacing each mixed-signal IC to its own receive channel for a side ultrasound scanning modality254where all transducer array elements of the ultrasound transducer array320are used to form the image such that there is no sub-aperture, or by a combination of groupings mixed-signal ICs and independent receive channels.

Referring now toFIG. 7, a schematic diagram of connections between the multiple mixed-signal ICs340,342,344,346is shown. According to some embodiments, the mixed-signal IC340is defined to be the “master” IC by setting the board-level strapping pins422to low voltage (or “000”) and the other mixed-signal ICs are defined by setting the board-level strapping pins to be “slave” ICs by setting the board-level strapping pins522to be “001” for mixed-signal IC342, the board-level strapping pins622to be “010” for mixed-signal IC344, and the board-level strapping pins722to be “011” for mixed-signal IC346.

The hardware of each mixed-signal IC340,342,344,346is identical. Similar to mixed-signal IC340, mixed-signal IC342includes a set of transmitters502, a 16:1 receiver multiplexer504, a transmit/receive switch506, analog circuitry508, a controller510, and input/output buffers512. The mixed-signal IC342further includes the board-level strapping pins522, connectivity pins524to the other mixed-signal ICs340,344,346, communication pins526to the other mixed-signal ICs340,344,346, capacitor pins528, and a low-voltage power supply pin530.

Mixed-signal IC344includes a set of transmitters602, a 16:1 receiver multiplexer604, a transmit/receive switch606, analog circuitry608, a controller610, and input/output buffers612. The mixed-signal IC344further includes the board-level strapping pins622, connectivity pins624to the other mixed-signal ICs340,342,346, communication pins626to the other mixed-signal ICs340,342,346, capacitor pins628, and a low-voltage power supply pin630.

Mixed-signal IC346includes a set of transmitters702, a 16:1 receiver multiplexer704, a transmit/receive switch706, analog circuitry708, a controller710, and input/output buffers712. The mixed-signal IC346further includes the board-level strapping pins722, connectivity pins724to the other mixed-signal ICs340,342,344, communication pins726to the other mixed-signal ICs340,342,344, capacitor pins728, and a low-voltage power supply pin730.

The connectivity pins424,524,624,724of the mixed-signal ICs340,342,344,346provide the power signals for high-voltage supply, low-voltage supply, and ground. The connectivity pins424,524,624,724further provide the receive signal for ultrasound signal from the master mixed-signal IC340and slave mixed-signal ICs342,344,346when a common differential transmission line is connected to the imaging assembly300. The imaging assembly300can be connected via a common differential transmission line to the IVUS imaging and pressure sensing console90.

The analog circuitries408,508,608,708are connected to the common differential transmission line to the imaging engine208via the patient interface module206ofFIG. 2. The analog circuitries408,508,608,708alternate driving the common differential transmission line. The analog circuitries408,508,608,708each include a low-noise amplifiers (LNA)409that is configurable to provide a variable gain to the ultrasonic signals that are received from the transducer array elements of the ultrasound transducer array320. This is advantageous because signal loss can result from the transmit/receive switch406and from transfer on the common differential transmission line to the external host. The LNA409boosts the ultrasound signals received on each mixed-signal IC340,342,344,346, and thereby improves the signal-to-noise ratio of the ultrasound signals received from the imaging assembly300.

The master mixed-signal IC340is further configured to multiplex the output signal of the pressure sensor330on the same differential transmission line that is used for the ultrasound transducer array signals. The communication pins426,526,626,726of the mixed-signal ICs340,342,344,346provide the digital clock signal, the digital transmit signal, and cyclic redundancy check (CRC) signals.

FIG. 8is a side view of an example of the imaging assembly300after forming.FIG. 9shows an end view of the imaging assembly300after forming. Referring now toFIGS. 8 and 9, the flexible substrate310is rolled into a tubular structure that in certain examples is approximately 1 mm in diameter. Thus, the ultrasound transducer array320can have a circular shape as shown inFIG. 9. The central axis of the imaging assembly300after forming is substantially clear of interference. The imaging assembly300after forming can be integrated into the sensor assembly section130of the catheter100(seeFIG. 4). In certain embodiments, the imaging assembly300can scan at a depth of about 3-4 cm with a frame rate of about 30 frames per second. In certain embodiments, the catheter100including the imaging assembly300are disposable after a single use.

Advantageously, the imaging assembly300after forming can transmit on any one of the transducer array elements of the ultrasound transducer array320, and can receive on any other transducer array element of the ultrasound transducer array320. For example, in embodiments where the ultrasound transducer array320includes 64 transducer array elements, and the imaging assembly300comprises the mixed-signal ICs340,342,344,346, each mixed-signal IC is configurable by a memory415to transmit on any one transducer array element of the 64 transducer array elements and receive on any one transducer array element of the 64 transducer array elements.

In some embodiments, the ultrasound signals that are received from a transducer array element of the ultrasound transducer array320can be multiplexed onto a single receiver channel. In alternative embodiments where the imaging assembly300includes four or more integrated circuits mounted on the substrate310, more than one integrated circuit is operatively connected on a first receive line to a first set of transducer array elements of the ultrasound transducer array320, and more than one other integrated circuit is operatively connect on a second receive line to a second set of transducer array elements. In certain embodiments, the first and second sets of transducer array elements are alternately arranged around a central axis of the imaging assembly300such as around the center of the end view of the imaging assembly300shown inFIG. 9.

As described, in certain embodiments the hardware of each mixed-signal IC340,342,344,346is the same. Thus, in certain embodiments the imaging assembly300can include at least two pressure sensors that are mounted on the substrate310, with a first pressure sensor being operatively connected to a first integrated circuit (e.g., mixed-signal IC340) that multiplexes a pressure signal from the first pressure sensor onto the first receive channel, and a second pressure sensor being operatively connected to a second integrated circuit (e.g., mixed-signal IC344) that multiplexes a pressure signal from the second pressure sensor onto the second receive channel.

In certain embodiments, the mixed-signal IC340,342,344,346connected to the first set of transducer array elements are driven by a first differential transmitter signal and a clock signal, and the mixed-signal IC340,342,344,346connected to the second set of transducer array elements are driven by a second differential transmitter signal and the clock signal, and the first and second differential transmittal signals are different.

As described above, a sub-aperture for performing the cylindrical ultrasound scanning modality252by the imaging assembly300can be optimized by programming the mixed-signal IC340,342,344,346to increase or decrease the number of transmit-receive elements within the sub-aperture of the ultrasound transducer array320.FIG. 17illustrates a first ultrasound image810of a target of interest812and a surrounding tissue814that is constructed using a sub-aperture having a first size800. In certain embodiments, the sub-aperture having the first size800includes 16 elements.FIG. 18illustrates a second ultrasound image820of a target of interest822and a surrounding tissue824that is constructed using a sub-aperture having a second size802. In certain embodiments, the sub-aperture having the second size802includes 20 elements.FIG. 19illustrates a third ultrasound image830of a target of interest832and a surrounding tissue834that is constructed using a sub-aperture having a third size804. In certain embodiments, the sub-aperture having the third size804includes 24 elements.

The lateral resolution and depth of penetration of an ultrasound image generally increases with increasing sub-aperture size of the ultrasound transducer array320. Thus, the third ultrasound image830that is constructed using sub-aperture having a third size804has a larger depth of penetration than the first and second ultrasound images810,820. However, the third ultrasound image830that is constructed using sub-aperture having a third size804has a slower frame rate for reproducing the ultrasound images.

The transmit-receive sequence and operational codes (opcodes) that are uploaded to the memory415of the mixed-signal IC340for execution by the controller410can program the imaging assembly300to have an optimum sub-aperture size for performing the cylindrical ultrasound scanning modality252for a desired clinical application.

FIG. 10is a partial sectional view of the distal end of an example endobronchial ultrasound (EBUS) bronchoscope1100. In certain embodiments, the EBUS bronchoscope1100is assembled and configured to perform the side ultrasound scanning modality254shown inFIG. 3. Additionally, while some embodiments described herein with reference to the EBUS bronchoscope1100ofFIG. 10are appropriate for EBUS bronchoscopes, other embodiments can be used in applications other than an EBUS bronchoscope. The EBUS bronchoscope1100can be delivered to a bronchus passage or airway through the working channel of a diagnostic or therapeutic bronchoscope.

In the embodiment shown, the EBUS bronchoscope1100includes a distal tip1110, a distal shaft1120, a sensor assembly section1200, and a cable harness1250. In some embodiments, the distal tip1110has an outer diameter between about 1 mm and about 3 mm. In certain embodiments, the distal tip1110has an outer diameter of about 2 mm. The outer diameter of the EBUS bronchoscope is sufficiently small for delivery through the working channel of a diagnostic or therapeutic bronchoscope. In some embodiments, the distal tip1110has a length between about 5 mm and about 20 mm. In certain embodiments, the distal tip1110has a length of about 10 mm. The distal tip1110further includes an atraumatic tip to minimize trauma to the bronchi.

The distal tip1110is bonded to the distal shaft1120. The distal shaft1120has a proximal end, a distal end, and a length extending between the proximal and distal ends. The distal shaft1120further includes a first lumen1122, a second lumen1124, and an exit port1126. The distal tip1110includes the sensor assembly section1200.

The sensor assembly section1200is coupled to the distal end of the cable harness1250that runs through the first lumen1122. The proximal end of the cable harness1250can be connected to an external host system such as the imaging engine208via the patient interface module206shown inFIG. 2. The second lumen1124may be used as a working lumen, such as for delivery of a biopsy needle. The EBUS bronchoscope1100can provide ultrasound image guidance during needle biopsy of a bronchial lymph node, a medical procedure that is performed to determine the stage of lung cancer.

FIGS. 11 and 12show top and bottom views of an example of an imaging assembly1300before forming. The imaging assembly1300can be included in the sensor assembly section1200that is shown inFIG. 10. As shown inFIGS. 11 and 12, the pre-formed imaging assembly1300includes a flexible substrate1310, an ultrasound transducer array1320, and mixed-signal ICs1340,1342,1344,1346.

The pre-formed imaging assembly1300has location features1380,1382that can aid in positioning and trimming during the forming operation. The pre-formed imaging assembly1300can include a plurality of capacitors, such as capacitors1360,1362,1364,1366,1368,1370,1372,1374. This chip-on-flex design provides technical advantages including low device cost via mass production (up to approximately 120 assemblies within a five square inch substrate), and geometrical and mechanical flexibility which is helpful for bronchoscopy applications.

The flexible substrate1310is a laminated structure that can include a coverlay, at least one electrical insulating layer, electrically conductive features, and adhesives. At least one insulating layer can be made of polyimide. A polyimide layer may be as thin as approximately 12 μm. The electrically conductive features can be etched from copper foils as thin as about 5 μm thick, or vapor deposited copper of about 2-4 μm thick, vapor deposited nickel of about 2-4 μm thick, or vapor deposited gold of about 0.5 μm thick. The flexible substrate1310can include electrical contacts such as pads for die (chip) attachment of components for the mixed-signal ICs1340,1342,1344,1346, and capacitors1360,1362,1364,1366,1368,1370,1372,1374.

The ultrasound transducer array1320includes an array of 64 elements where each element includes at least one piezoelectric micromachined ultrasound transducer (pMUT). In some embodiments, the pMUTs have a resonant frequency between about 5 MHz and about 40 MHz. In certain embodiments, the pMUTs can have a resonant frequency of about 9.0 MHz. The dimensions of the ultrasound transducer array1320are approximately 8 mm by 1.5 mm by 0.1 mm. In some embodiments, the array pitch is between about 30 μm and about 150 μm. In certain embodiments, the array pitch is approximately 125 μm for a 9.0 MHz ultrasound transducer array.

FIG. 13schematically shows connections between the multiple mixed-signal ICs1340,1342,1344,1346. The mixed-signal ICs1340,1342,1344,1346are similar to the mixed-signal integrated circuits (ICs)340,342,344,346of the imaging assembly300described above with reference toFIGS. 5-9, and the mixed-signal IC1340can have the same components as the mixed-signal IC340shown inFIG. 6.

In some embodiments, the mixed-signal IC1340is defined to be the “master” IC by setting the board-level strapping pins1422to low voltage (or “000”) and the other mixed-signal ICs are defined by setting the board-level strapping pins to be “slave” ICs by setting the board-level strapping pins1522to be “001” for mixed-signal IC1342, the board-level strapping pins1622to be “010” for mixed-signal IC1344, and the board-level strapping pins1722to be “011” for mixed-signal IC1346.

The mixed-signal IC1340includes a set of transmitters1402, a 16:1 receiver multiplexer1404, a transmit/receive switch1406, analog circuitry1408, a controller1410, and input/output buffers1412. The mixed-signal IC1340further includes board-level strapping pins1422, connectivity pins1424to the other mixed-signal ICs1342,1344,1346, communication pins1426to the other mixed-signal ICs1342,1344,1346, receive output pin1428, and a low-voltage power supply pin1430.

The mixed-signal IC1342includes a set of transmitters1502, a 16:1 receiver multiplexer1504, a transmit/receive switch1506, analog circuitry1508, a controller1510, and input/output buffers1512. The mixed-signal IC1342further includes board-level strapping pins1522, connectivity pins1524to the other mixed-signal ICs1340,1344,1346, communication pins1526to the other mixed-signal ICs1340,1344,1346, receive output pin1528, and a low-voltage power supply pin1530.

The mixed-signal IC1344includes a set of transmitters1602, a 16:1 receiver multiplexer1604, a transmit/receive switch1606, analog circuitry1608, a controller1610, and input/output buffers1612. The mixed-signal IC1344further includes board-level strapping pins1622, connectivity pins1624to the other mixed-signal ICs1340,1342,1346, communication pins1626to the other mixed-signal ICs1340,1342,1346, receive output pin1628, and a low-voltage power supply pin1630.

The mixed-signal IC1346includes a set of transmitters1702, a 16:1 receiver multiplexer1704, a transmit/receive switch1706, analog circuitry1708, a controller1710, and input/output buffers1712. The mixed-signal IC1346further includes board-level strapping pins1722, connectivity pins1724to the other mixed-signal ICs1340,1342,1344, communication pins1726to the other mixed-signal ICs1340,1342,1344, receive output pin1728, and a low-voltage power supply pin1730.

The mixed-signal IC1340further includes interfaces for power and data pins1420to an external host system such as the imaging engine208via the patient interface module206shown inFIG. 2. The power and data pins1420provide power signals for high-voltage supply, low-voltage supply, and ground. The power and data pins1420further provide analog signals for a high-speed LVDS for transmit signals. The power and data pins1420still further provide a digital signal for an input clock signal.

The receive output pins1428,1528,1628,1728of the mixed-signal ICs1340,1342,1344,1346are each coupled to a single-ended transmission line. Use of the receive output pins1428,1528,1628,1728of the mixed-signal ICs1340,1342,1344,1346enables simultaneous measurements of received ultrasound signals from multiple ultrasound transducer elements. This can reduce the time to acquire an ultrasound image.

Additionally, ultrasound signals can be received from any one of the mixed-signal ICs1340,1342,1344,1346, or from multiple mixed-signal ICs, or from all of the mixed-signal ICs such that ultrasound signals can be received from any of the connected ultrasound transducer elements, one per mixed-signal IC. Multiple receive channels can be included, one for each mixed-signal IC, to increase the bandwidth of the imaging assembly1300and thereby reduces the time to acquire an ultrasound image.

The connectivity pins1424,1524,1624,1724of the mixed-signal ICs1340,1342,1344,1346provide power signals for high-voltage supply, low-voltage supply, and ground. The communication pins1426,1526,1626,1726of the mixed-signal ICs1340,1342,1344,1346provide digital clock signal, digital transmit signal, and CRC signals.

FIG. 14shows an end view of the imaging assembly1300after forming. The flexible substrate1310is folded such that the imaging assembly1300has a rectangular cross-sectional shape, and the mixed-signal IC1346and capacitor1374are positioned below the ultrasound transducer array1320. The ultrasound transducer array1320is encapsulated by a lens1390that protects the ultrasound transducer array1320from potential damage during use and provides focusing of the ultrasound energy to improve image performance. The imaging assembly1300after forming can be integrated into the sensor assembly section1200of the EBUS bronchoscope1100ofFIG. 10.

The EBUS bronchoscope1100can be used with an external host system, such as the IVUS imaging and pressure sensing console90shown inFIG. 1, to guide a needle biopsy of a bronchial lymph node for lung cancer staging. The imaging assembly1300can be used to perform ultrasound imaging by acquiring a complete data set where all combinations of transmit and receive pairs for the 64-element array are processed. As an illustrative example, the mixed-signal IC1340transmits on a first transmit channel, and ultrasound signals are simultaneously received from a first receive channel on each of the mixed-signal ICs1340,1342,1344,1346. This transmit-receive sequence can be repeated for remaining receive channels of the mixed-signal ICs1340,1342,1344,1346. This sequence can be further repeated for each transmit channel of each mixed-signal IC.

Advantageously, the imaging assembly1300can transmit on one transducer array element of the ultrasound transducer array1320, and simultaneously receive on four transducer array elements of the ultrasound transducer array1320(i.e., one transducer array element per mixed-signal IC1340,1342,1344,1346).

In some embodiments, the imaging assembly1300can be expanded to include eight mixed-signal ICs. In such embodiments, the imaging assembly1300can transmit on one transducer array element of the ultrasound transducer array1320, and simultaneously receive on eight transducer array elements of the ultrasound transducer array1320(i.e., one transducer array element per mixed-signal IC).

The EBUS bronchoscope1100may utilize synthetic aperture imaging techniques to enable array imaging with a reduced number of transmission lines. This enables reduced size, reduced power consumption and heat generation, and reduced cost.

Additionally, a sub-aperture for performing the side ultrasound scanning modality254by the imaging assembly1300can be optimized by programming the mixed-signal ICs1340,1342,1344,1346to increase or decrease the number of transmit-receive elements within the sub-aperture of the ultrasound transducer array1320, similar to the description provided above with respect toFIGS. 17-19.

In embodiments where the imaging assembly1300includes eight integrated circuits, each integrated circuit can be operatively connected to a dedicated receive channel, and the imaging assembly1300is configurable to perform an ultrasound scanning modality that includes transmitting an ultrasound signal on one element of the ultrasound transducer array, and receiving ultrasound signals on eight elements of the ultrasound transducer array. In some embodiments, a SRAM with size 1024×10 bits can support system opcodes for one transmit channel and eight receive channels, and an external host system can include eight receive channels. By increasing the size of SRAM, the external host system can address the additional mixed-signal ICs.

Another example embodiment can include an imaging assembly having a 64-element ultrasound transducer array and eight mixed-signal ICs. Only eight of the 16 transmitters of each mixed-signal IC are connected to transducer elements. An external host system includes eight channels. With the use no-op events an external host system and imaging assembly can be used to reduce the acquisition time.

Another example embodiment can include an imaging assembly having a mixed-signal IC that multiplexes to a number of ultrasound transducer elements different than sixteen. Another example embodiment can include an imaging assembly having a 2D ultrasound transducer array, and the array is a sparse array for providing a forward looking 3D ultrasound scanning modality.

FIG. 15illustrates a method1800of performing ultrasound imaging using a programmable imaging assembly. The method1800includes an operation1802of selecting a desired ultrasound scanning modality for an imaging assembly. For example, operation1802can include selecting between the cylindrical ultrasound scanning modality252, the side ultrasound scanning modality254, and the forward looking 3D ultrasound scanning modality256shown inFIG. 3.

Next, the method1800includes an operation1804of forming and assembling the imaging assembly based on the selected ultrasound scanning modality. In certain embodiments, the imaging assembly is formed by rolling a flexible substrate of the imaging assembly around a sensor assembly section of the catheter or endoscope such that imaging assembly has a tubular structure and a circular cross-sectional shape, such as shown in the embodiment ofFIG. 9. In further embodiments, the imaging assembly is formed by folding a flexible substrate of the imaging assembly around a sensor assembly section of the catheter or endoscope such that imaging assembly has a tubular structure and a rectangular cross-sectional shape, such as shown in the embodiment ofFIG. 14. In yet further embodiments, the imaging assembly is formed by applying a flexible substrate of the imaging assembly to a surface of a catheter or endoscope without rolling or folding the flexible substrate such that the imaging assembly is substantially flat.

Next, the method1800includes an operation1806of connecting the imaging assembly to a patient interface module (seeFIG. 2), and powering the imaging assembly on to perform an initialization mode that includes uploading a transmit-receive sequence and opcodes to a memory of the imaging assembly. The transmit-receive sequence and opcodes that are uploaded to the memory of the imaging assembly configure the imaging assembly to perform the selected ultrasound scanning modality.

Next, the method1800includes an operation1808of performing a mission mode which includes using the imaging assembly to perform the selected ultrasound scanning modality. During mission mode, ultrasound signal data from the imaging assembly is acquired and processed by an imaging engine for displaying ultrasound images in accordance with the selected ultrasound scanning modality on a display device such as the display computer or tablet210ofFIG. 2.

In certain embodiments, an input device such as the display computer or tablet210can be used by a user to select/change imaging parameters within the selected ultrasound scanning modality. For example, an integrated circuit clock frequency in the mission mode can be varied to adjust the transmit-receive repetition rate. Also, a differential transmit signal in the mission mode can be varied to change a center frequency of the imaging assembly. Additionally, the differential transmit signal in the mission mode can be varied to adjust an operation of the transmit/receive switch to optimize near-field imaging performance.

FIG. 16illustrates an exemplary architecture of a computing device1900which can be used to implement aspects of the present disclosure, such as the functions of the IVUS imaging and pressure sensing console90, the patient interface module206, the imaging engine208, or the display computer or tablet210that are described above. The computing device1900includes a processing unit1902, a system memory1908, and a system bus1920that couples the system memory1908to the processing unit1902.

The processing unit1902is an example of a processing device such as a central processing unit (CPU). The system memory1908includes a random-access memory (“RAM”)1910and a read-only memory (“ROM”)1912. A basic input/output logic containing the basic routines that help to transfer information between elements within the computing device1900, such as during startup, is stored in the ROM1912.

The computing device1900can also include a mass storage device1914that stores software instructions and data. The mass storage device1914is connected to the processing unit1902through a mass storage controller connected to the system bus1920. The mass storage device1914and its associated computer-readable data storage media provide non-volatile, non-transitory storage for the computing device1900.

Although the description of computer-readable data storage media herein refers to a mass storage device, it should be appreciated by those skilled in the art that computer-readable data storage media can be any available non-transitory, physical device or article of manufacture from which the device can read data and/or instructions. The mass storage device1914is an example of a computer-readable storage device.

Computer-readable data storage media include volatile and non-volatile, removable and non-removable media implemented in any method or technology for storage of information such as computer-readable software instructions, data structures, program modules or other data. Example types of computer-readable data storage media include, but are not limited to, RAM, ROM, EPROM, EEPROM, flash memory or other solid-state memory technology, or any other medium which can be used to store information, and which can be accessed by the device.

The computing device1900may operate in a networked environment using logical connections to remote network devices through the network1922, such as a local network, the Internet, or another type of network. The device connects to the network1922through a network interface unit1904connected to the system bus1920. The network interface unit1904may also be utilized to connect to other types of networks and remote computing systems.

The computing device1900can also include an input/output controller1906for receiving and processing input from a number of input devices. Similarly, the input/output controller1906may provide output to a number of output devices.

The mass storage device1914and the RAM1910can store software instructions and data. The software instructions can include an operating system1918suitable for controlling the operation of the device. The mass storage device1914and/or the RAM1910also store software instructions1916, that when executed by the processing unit1902, cause the device to provide the functionality of the device discussed in this document. For example, the mass storage device1914and/or the RAM1910can store software instructions that, when executed by the processing unit1902, cause the imaging engine208to program and operate the imaging assembly202via the patient interface module206, as shown inFIG. 2.

In accordance with an aspect of the present invention, an intraluminal medical device includes an elongated body including a first section having a first sensor adapted to transmit and receive ultrasound pressure, a second sensor adapted to measure a physiological parameter, and a first integrated circuit that is connected to the first sensor and the second sensor. The first section further includes a lumen adapted to receive a guide wire. The elongated body further includes a second section that is bonded to the first section and has a lumen adapted to house a communication assembly. The first sensor may include an ultrasound transducer array. The first integrated circuit includes transmit and receive electronics to control the first sensor. The second sensor may include a piezoresistive sensor, such as a Wheatstone bridge, for measuring blood pressure. The first section may further include at least one additional integrated circuit that is connected to the first integrated circuit. The at least one additional integrated circuit is further connected to the first sensor. The communication assembly may include a single transmission line to receive the signals from both the first sensor and the second sensor.

In accordance with another aspect of the present invention, an intraluminal medical device includes an elongated body including a first section having a sensor adapted to transmit and receive ultrasound pressure and a first integrated circuit that is connected to the sensor. The elongated body further includes a second section that is bonded to the first section, a first lumen adapted to house a communication assembly, and a second lumen adapted to deliver a needle. The sensor may include an ultrasound transducer array. The first integrated circuit includes transmit and receive electronics to control the first sensor. The first section may further include at least one additional integrated circuit that is connected to the first integrated circuit. The at least one additional integrated circuit is further connected to the sensor. The communication assembly includes a transmission line to receive signals from the first integrated circuit. The communication assembly may further include at least one transmission line to receive signals from the at least one additional integrated circuit.