Periodic Reporting for period 1 - PALPABLE (Multi-sensing tool for Minimally Invasive Surgery)
Período documentado: 2023-01-01 hasta 2024-06-30
Minimally invasive surgery (MIS) refers to surgical procedures with minimal incisions made to the patient. In MIS, the operating tools are mounted on laparoscopic shafts, and enter the patients’ body through incisions smaller than 2 cm in diameter. The surgeon operates by manipulation of the laparoscopic shafts. MIS leads to less tissue damage, reduced hospital stays, decreased chance of infection, as well as improved cosmetic results. The number of MIS surgeries performed worldwide is consistently gaining ground over traditional open surgery in recent years.
The success of any surgery heavily depends on the information that is available to the operating surgeon, among several other factors. Traditional open surgery offers the advantage of easy access to the internal organs, which can be inspected visually or even manually. Palpation is the technique in which a doctor evaluates the health of tissue by using their sense of touch. This technique can indicate the presence and extent of tumorous tissue, which is usually harder compared with its surrounding healthy tissue. Palpation is easily applied in traditional open surgery; however, in MIS, the small size of incisions limits the surgeons’ ability to access internal organs by using their hands.
The inability to perform tissue examination through manual palpation is a significant drawback of MIS. This type of information has historically been valuable in locating the margins of tumorous tissue. Without the sense of touch, and under obstructed vision, it is often difficult to ensure that all damaged tissue is removed from the patient’s body. Failing to remove some tumorous regions from a diseased organ can lead to an unsuccessful surgery and high chances of repeated tumorous growth.
PALPABLE is a Horizon Europe project that aims to provide this type of sensory feedback back to the surgeon, and in this way eliminate one of the most significant drawbacks of MIS. By introducing palpation feedback in MIS surgery, PALPABLE aims to broaden the applications of MIS, increase the successful localization of all cancerous tissue on an affected organ and surrounding regions, and finally to improve surgery outcomes.
To achieve this, several challenges need to be overcome. The PALPABLE palpation tool will have to be very precise, to be able to replace the highly accurate and delicate sense of a trained surgeons’ touch. Another challenge is the minimization of the tool, as it will need to be inserted through a small laparoscopic incision to be useful in MIS. Once inside the patient, the tool should be able to scan a large area across the target organ. Since the laparoscopic shaft is constrained by the incision points, the tool must be able readjust its own shape to perform the scanning motion.
The success of any surgery heavily depends on the information that is available to the operating surgeon, among several other factors. Traditional open surgery offers the advantage of easy access to the internal organs, which can be inspected visually or even manually. Palpation is the technique in which a doctor evaluates the health of tissue by using their sense of touch. This technique can indicate the presence and extent of tumorous tissue, which is usually harder compared with its surrounding healthy tissue. Palpation is easily applied in traditional open surgery; however, in MIS, the small size of incisions limits the surgeons’ ability to access internal organs by using their hands.
The inability to perform tissue examination through manual palpation is a significant drawback of MIS. This type of information has historically been valuable in locating the margins of tumorous tissue. Without the sense of touch, and under obstructed vision, it is often difficult to ensure that all damaged tissue is removed from the patient’s body. Failing to remove some tumorous regions from a diseased organ can lead to an unsuccessful surgery and high chances of repeated tumorous growth.
PALPABLE is a Horizon Europe project that aims to provide this type of sensory feedback back to the surgeon, and in this way eliminate one of the most significant drawbacks of MIS. By introducing palpation feedback in MIS surgery, PALPABLE aims to broaden the applications of MIS, increase the successful localization of all cancerous tissue on an affected organ and surrounding regions, and finally to improve surgery outcomes.
To achieve this, several challenges need to be overcome. The PALPABLE palpation tool will have to be very precise, to be able to replace the highly accurate and delicate sense of a trained surgeons’ touch. Another challenge is the minimization of the tool, as it will need to be inserted through a small laparoscopic incision to be useful in MIS. Once inside the patient, the tool should be able to scan a large area across the target organ. Since the laparoscopic shaft is constrained by the incision points, the tool must be able readjust its own shape to perform the scanning motion.
The PALPABLE project has been running for 18 months. During this period, there has been significant progress in several key elements of the palpation sensing device.
The first few months focused on the consideration and subsequent derivation of the performance requirements for the PALPABLE device. The PALPABLE consortium collaborated with a group of surgical experts from the European Association for Endoscopic Surgery, to identify the desired functionalities of the tool.
The PALPABLE sensing device requires the development of several modules, that will cooperate in performing tissue palpation. The team has designed a soft pneumatically actuated device, that is able to alter its shape in a controlled fashion. This can be used to configure the PALPABLE sensors inside the patient, to allow palpation of hard-to-reach areas.
Secondly, the PALPABLE device shall be able to detect changes in tissue stiffness across the scanned area. To measure stiffness, it is required to combine concurrent measurements of tissue deformation as well as of resulting force.
To measure deformation, the team has developed a curvature sensing module, which can accurately detect its own deformation using photonic signals: this requires the manufacture of miniature photonic circuits and offers a high resolution in a very small size.
To measure force, the PALPABLE device includes several force or pressure sensors on its outer surface. The force sensor consists of a pressurized membrane in the shape of a dome, which contacts the palpated tissue. The membrane is interrogated using an optical circuit.
In another approach to force sensing, flexible photonic circuit arrays situated around the probe are used to detect contact pressure and calculate force levels and distribution with detail.
Photonic circuits are utilized in several of the PALPABLE devices’ modules. Research efforts have focused on the development of low-cost optical guides. The progress in this module is significant for the operation not only of the photonic circuit arrays, but also for the curvature sensors and the pressure sensing membranes.
The force and deformation measurements are combined into a stiffness measurement, and they are assigned to specific positions of the examined tissue surface, using specialized proprioception and localization software that is developed for PALPABLE.
Finally, PALPABLE shall operate using a custom readout unit, which will power and interrogate the photonics-based sensors. The development of the readout unit is led by targets on device cost and accuracy. Another significant aspect of the PALPABLE tool's operation is the pneumatic actuation, which is utilized to pressurize the force-sensing membranes and to steer the probe inside the patient. This is also under development, with first versions of the pneumatic control box already available.
Preliminary integration efforts targeted the development of a miniature probe, measuring 15mm in diameter: a major challenge of which was how to combine the various modules in such a small space. Initial efforts focused on the derivation of a detailed layout of the probe, to identify the available space for the modules under development. Overall, the technical efforts of M10-M18 have led to the successful manufacture and testing of experimental prototypes for all the sensing modules, with promising initial results. The next months will focus on the exploration of alternative sensing methods, and the improvement of the current prototypes, before the integration tasks that are scheduled for later in the project.
The first few months focused on the consideration and subsequent derivation of the performance requirements for the PALPABLE device. The PALPABLE consortium collaborated with a group of surgical experts from the European Association for Endoscopic Surgery, to identify the desired functionalities of the tool.
The PALPABLE sensing device requires the development of several modules, that will cooperate in performing tissue palpation. The team has designed a soft pneumatically actuated device, that is able to alter its shape in a controlled fashion. This can be used to configure the PALPABLE sensors inside the patient, to allow palpation of hard-to-reach areas.
Secondly, the PALPABLE device shall be able to detect changes in tissue stiffness across the scanned area. To measure stiffness, it is required to combine concurrent measurements of tissue deformation as well as of resulting force.
To measure deformation, the team has developed a curvature sensing module, which can accurately detect its own deformation using photonic signals: this requires the manufacture of miniature photonic circuits and offers a high resolution in a very small size.
To measure force, the PALPABLE device includes several force or pressure sensors on its outer surface. The force sensor consists of a pressurized membrane in the shape of a dome, which contacts the palpated tissue. The membrane is interrogated using an optical circuit.
In another approach to force sensing, flexible photonic circuit arrays situated around the probe are used to detect contact pressure and calculate force levels and distribution with detail.
Photonic circuits are utilized in several of the PALPABLE devices’ modules. Research efforts have focused on the development of low-cost optical guides. The progress in this module is significant for the operation not only of the photonic circuit arrays, but also for the curvature sensors and the pressure sensing membranes.
The force and deformation measurements are combined into a stiffness measurement, and they are assigned to specific positions of the examined tissue surface, using specialized proprioception and localization software that is developed for PALPABLE.
Finally, PALPABLE shall operate using a custom readout unit, which will power and interrogate the photonics-based sensors. The development of the readout unit is led by targets on device cost and accuracy. Another significant aspect of the PALPABLE tool's operation is the pneumatic actuation, which is utilized to pressurize the force-sensing membranes and to steer the probe inside the patient. This is also under development, with first versions of the pneumatic control box already available.
Preliminary integration efforts targeted the development of a miniature probe, measuring 15mm in diameter: a major challenge of which was how to combine the various modules in such a small space. Initial efforts focused on the derivation of a detailed layout of the probe, to identify the available space for the modules under development. Overall, the technical efforts of M10-M18 have led to the successful manufacture and testing of experimental prototypes for all the sensing modules, with promising initial results. The next months will focus on the exploration of alternative sensing methods, and the improvement of the current prototypes, before the integration tasks that are scheduled for later in the project.
In M18 of the PALPABLE project, it is still early for the demonstration of significant results and impact. Preliminary results have been obtained, paving the way towards the achievement of the project results and broader impact.
We are currently making progress towards the achievement of significant technological advances in pneumatic end-effectors, non-planar photonics circuits, and accurate stiffness and tissue curvature estimation.
Furthermore, we have demonstrated PALPABLE outcomes via our active participation in various events of the robotics and MIS communities.
At the end of the project, we expect to have a prototype for a novel laparoscopic palpation tool that incorporates multiple sensing modalities in a low-cost, miniature size device. Our aim is to demonstrate the device’s operation by successful stiffness evaluation trials on a phantom organ.
Finally, we have also taken steps to investigate the use of our sensing probe in the context of robotically assistive surgery. This is expected to further increase our device's usability and reach.
We are currently making progress towards the achievement of significant technological advances in pneumatic end-effectors, non-planar photonics circuits, and accurate stiffness and tissue curvature estimation.
Furthermore, we have demonstrated PALPABLE outcomes via our active participation in various events of the robotics and MIS communities.
At the end of the project, we expect to have a prototype for a novel laparoscopic palpation tool that incorporates multiple sensing modalities in a low-cost, miniature size device. Our aim is to demonstrate the device’s operation by successful stiffness evaluation trials on a phantom organ.
Finally, we have also taken steps to investigate the use of our sensing probe in the context of robotically assistive surgery. This is expected to further increase our device's usability and reach.