Mitral regurgitation is one of the most common structural heart diseases, significantly diminishing the quality of life, and can be fatal in severe cases. This condition mainly affects the elderly, who often cannot undergo open-chest surgery due to its invasive nature. Transcatheter Mitral Valve Repair (TMVR) offers a less invasive alternative, reducing trauma and shortening hospital stays. During this procedure, an interventionist maneuvers a transcatheter system to deliver an implant towards the mitral valve via the femoral vein while a sonographer operates a Transesophageal Echocardiography (TEE) probe to generate real-time imaging of the heart chamber, guiding the intervention with visual information. However, this life-saving procedure is currently limited to a few clinics with experienced surgical teams due to the complexity of maneuvering the tendon-driven surgical instruments within a confined human body without damaging surrounding tissues. This complexity demands a steep learning curve for surgeons and close teamwork between the interventionist and sonographer. Moreover, exposure to radiative fluoroscopy requires the surgical team to wear heavy protective aprons, which can lead to ergonomic challenges and potential long-term radiative harm during prolonged procedures. To address these challenges, this thesis proposes two robot-assisted systems—the robot-assisted transcatheter system and the robot-assisted TEE system—with task autonomy control features semi-autonomous operation. In the intravascular phase, a path-tracking algorithm safely navigates the Sheath Guide Catheter (SGC) through the vessel, utilizing real-time pose and shape measurements from an Electromagnetic (EM) sensor and a Fiber Bragg Grating (FBG) sensor. A high-level controller calculates the trajectory for the robot to follow the vessel’s centerline, while a low-level controller commands local actuators based on joint space input. In the intracardiac phase, the Clip Delivery Catheter (CDC) is robotized and autonomously navigates towards the mitral valve in the left atrium. The robotic system integrated a learning-based path planner, an inverse kinematics model, and a closed-loop feedback control on a commercial MitraClip system. The robot-assisted TEE system plays a crucial role in providing echo imaging during the intervention. This thesis introduces a novel robotic TEE system that features actuators across all four degrees of freedom and an easily disassembled design for post-procedure sanitization. Additionally, the inherent hysteresis effect of the tendon-driven TEE probe is compensated for using offline data identification. To further enhance the autonomy of the robotic system and provide direct assistance to the interventionist, a collaborative control framework is developed. This framework allows the interventionist to directly control the imaging view, enabling the TEE probe to autonomously track the catheter’s movement and maintain its visibility within the echo image. Overall, the proposed robot-assisted systems were validated in a realistic in-vitro setup, demonstrating their potential for practical clinical application. The successful implementation of these systems in the clinical environment could revolutionize TMVR procedure by significantly reducing the physical strain on surgeons, minimizing radiation exposure, and enhancing procedural accuracy and safety. This research establishes a foundational framework for future innovations in robotic-assisted minimally invasive procedures, potentially leading to more adaptive, intelligent systems capable of autonomously handling a broader range of surgical tasks.
Il rigurgito mitralico è una delle malattie cardiache strutturali più comuni, che riduce signiffcativamente la qualità della vita e può essere fatale nei casi gravi. Questa condizione colpisce principalmente gli anziani, che spesso non possono sottoporsi a chirurgia a cuore aperto a causa della sua natura invasiva. La Riparazione Transcatetere della Valvola Mitrale (TMVR) offre un’alternativa meno invasiva, riducendo il trauma e accorciando i tempi di degenza ospedaliera. Durante questa procedura, un interventista manovra un sistema transcatetere per posizionare un impianto verso sulla valvola mitrale accedendo dalla vena femorale, mentre un ecograffsta opera una sonda di Ecocardiograffa Transesofagea (TEE) per generare immagini in tempo reale della camera cardiaca, guidando l’intervento con informazioni visive. Tuttavia, questa procedura salvavita è attualmente limitata a pochi centri specializzati. La manipolazione di strumenti chirurgici guidati da tendini all’interno del corpo umano è estremamente complessa e richiede un’elevata precisione per evitare il danneggiamento dei tessuti circostanti. Questa difffcoltà comporta una curva di apprendimento ripida per i chirurghi. Inoltre, la procedura richiede una stretta collaborazione tra l’interventista e l’ecograffsta. L’uso della ffuoroscopia espone il team chirurgico a radiazioni ionizzanti. Per proteggersi, gli operatori devono indossare grembiuli piombati, che possono causare disagi ergonomici. L’esposizione prolungata rappresenta anche un rischio per la salute a lungo termine. Per affrontare queste sffde, questa tesi propone due sistemi robotici assistiti: il sistema robotico per la procedura transcatetere e il sistema robotico per la TEE. Entrambi integrano funzionalità di controllo, consentendo un funzionamento semi-autonomo. Nella fase intravascolare, un algoritmo di tracciamento del percorso consente la navigazione sicura del catetere guida (Sheath Guide Catheter, SGC) all’interno del vaso. Questo processo sfrutta misurazioni in tempo reale della posizione e della forma del catetere, acquisite tramite un sensore elettromagnetico (EM) e un sensore a reticolo di ffbra di Bragg (FBG). Un controllore di alto livello calcola la traiettoria afffnché il robot segua la linea centrale del vaso, mentre un controllore di basso livello comanda gli attuatori locali in base agli input nello spazio dei giunti. Nella fase intracardiaca, il catatere di rilascio dellaclip (Clip Delivery Catheter, CDC) è robotizzato e viene autonomamente guidato verso la valvola mitrale all’interno dell’atrio sinistro. Il sistema robotico integra un pianiffcatore di traiettoria basato sull’apprendimento, un modello di cinematica inversa e un controllo in retroazione a ciclo chiuso applicato a un sistema commerciale MitraClip. Il sistema TEE assistito da robot svolge un ruolo cruciale nel fornire l’imaging ecograffco durante l’intervento. Questa tesi introduce un nuovo sistema robotico TEE che presenta attuatori su tutti e quattro i gradi di libertà e un design facilmente smontabile per la saniffcazione post-procedura. Inoltre, l’effetto di isteresi intrinseco della sonda TEE, azionata da tendini, è compensato utilizzando l’identiffcazione dei dati offfine. Per aumentare ulteriormente il livello di autonomia del sistema robotico e fornire assistenza diretta all’interventista, è stato sviluppato un framework di controllo collaborativo. Questo framework consente all’interventista di controllare direttamente la vista dell’immagine, permettendo alla sonda TEE di seguire autonomamente il movimento del catetere e mantenere la sua visibilità nell’immagine ecograffca. Nel complesso, i sistemi assistiti da robot proposti sono stati validati in una conffgurazione in vitro realistica, dimostrando il loro potenziale per applicazioni cliniche pratiche. L’implementazione di successo di questi sistemi nell’ambiente clinico potrebbe rivoluzionare la procedura TMVR riducendo signiffcativamente il carico ffsico sui chirurghi, minimizzando l’esposizione alle radiazioni e migliorando l’accuratezza e la sicurezza delle procedure. Questa ricerca stabilisce un quadro fondamentale per future innovazioni nelle procedure minimamente invasive assistite da robot, potenzialmente portando a sistemi più adattivi e intelligenti capaci di gestire autonomamente una gamma più ampia di compiti chirurgici.
Toward task autonomy on robot-assisted transcatheter mitral valve repair procedure
Zhang, Xiu
2024/2025
Abstract
Mitral regurgitation is one of the most common structural heart diseases, significantly diminishing the quality of life, and can be fatal in severe cases. This condition mainly affects the elderly, who often cannot undergo open-chest surgery due to its invasive nature. Transcatheter Mitral Valve Repair (TMVR) offers a less invasive alternative, reducing trauma and shortening hospital stays. During this procedure, an interventionist maneuvers a transcatheter system to deliver an implant towards the mitral valve via the femoral vein while a sonographer operates a Transesophageal Echocardiography (TEE) probe to generate real-time imaging of the heart chamber, guiding the intervention with visual information. However, this life-saving procedure is currently limited to a few clinics with experienced surgical teams due to the complexity of maneuvering the tendon-driven surgical instruments within a confined human body without damaging surrounding tissues. This complexity demands a steep learning curve for surgeons and close teamwork between the interventionist and sonographer. Moreover, exposure to radiative fluoroscopy requires the surgical team to wear heavy protective aprons, which can lead to ergonomic challenges and potential long-term radiative harm during prolonged procedures. To address these challenges, this thesis proposes two robot-assisted systems—the robot-assisted transcatheter system and the robot-assisted TEE system—with task autonomy control features semi-autonomous operation. In the intravascular phase, a path-tracking algorithm safely navigates the Sheath Guide Catheter (SGC) through the vessel, utilizing real-time pose and shape measurements from an Electromagnetic (EM) sensor and a Fiber Bragg Grating (FBG) sensor. A high-level controller calculates the trajectory for the robot to follow the vessel’s centerline, while a low-level controller commands local actuators based on joint space input. In the intracardiac phase, the Clip Delivery Catheter (CDC) is robotized and autonomously navigates towards the mitral valve in the left atrium. The robotic system integrated a learning-based path planner, an inverse kinematics model, and a closed-loop feedback control on a commercial MitraClip system. The robot-assisted TEE system plays a crucial role in providing echo imaging during the intervention. This thesis introduces a novel robotic TEE system that features actuators across all four degrees of freedom and an easily disassembled design for post-procedure sanitization. Additionally, the inherent hysteresis effect of the tendon-driven TEE probe is compensated for using offline data identification. To further enhance the autonomy of the robotic system and provide direct assistance to the interventionist, a collaborative control framework is developed. This framework allows the interventionist to directly control the imaging view, enabling the TEE probe to autonomously track the catheter’s movement and maintain its visibility within the echo image. Overall, the proposed robot-assisted systems were validated in a realistic in-vitro setup, demonstrating their potential for practical clinical application. The successful implementation of these systems in the clinical environment could revolutionize TMVR procedure by significantly reducing the physical strain on surgeons, minimizing radiation exposure, and enhancing procedural accuracy and safety. This research establishes a foundational framework for future innovations in robotic-assisted minimally invasive procedures, potentially leading to more adaptive, intelligent systems capable of autonomously handling a broader range of surgical tasks.| File | Dimensione | Formato | |
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https://hdl.handle.net/10589/236753