Imaging skins: stretchable and conformable on-organ beta particle detectors for radioguided surgery

While radioguided surgery (RGS) traditionally relied on detecting gamma rays, direct detection of beta particles could facilitate the detection of tumour margins intraoperatively by reducing radiation noise emanating from distant organs, thereby improving the signal-to-noise ratio of the imaging technique. In addition, most existing beta detectors do not offer surface sensing or imaging capabilities. Therefore, we explore the concept of a stretchable scintillator to detect beta-particles emitting radiotracers that would be directly deployed on the targeted organ. Such detectors, which we refer to as imaging skins, would work as indirect radiation detectors made of light-emitting agents and biocompatible stretchable material. Our vision is to detect scintillation using standard endoscopes routinely employed in minimally invasive surgery. Moreover, surgical robotic systems would ideally be used to apply the imaging skins, allowing for precise control of each component, thereby improving positioning and task repeatability. While still in the exploratory stages, this innovative approach has the potential to improve the detection of tumour margins during RGS by enabling real-time imaging, ultimately improving surgical outcomes

Autonomous pick-and-place using the dVRK.

PURPOSE: Robotic-assisted partial nephrectomy (RAPN) is a tissue-preserving approach to treating renal cancer, where ultrasound (US) imaging is used for intra-operative identification of tumour margins and localisation of blood vessels. With the da Vinci Surgical System (Sunnyvale, CA), the US probe is inserted through an auxiliary access port, grasped by the robotic tool and moved over the surface of the kidney. Images from US probe are displayed separately to the surgical site video within the surgical console leaving the surgeon to interpret and co-registers information which is challenging and complicates the procedural workflow. METHODS: We introduce a novel software architecture to support a hardware soft robotic rail designed to automate intra-operative US acquisition. As a preliminary step towards complete task automation, we automatically grasp the rail and position it on the tissue surface so that the surgeon is then able to manipulate manually the US probe along it. RESULTS: A preliminary clinical study, involving five surgeons, was carried out to evaluate the potential performance of the system. Results indicate that the proposed semi-autonomous approach reduced the time needed to complete a US scan compared to manual tele-operation. CONCLUSION: Procedural automation can be an important workflow enhancement functionality in future robotic surgery systems. We have shown a preliminary study on semi-autonomous US imaging, and this could support more efficient data acquisition

A Fluidic Soft Robot for Needle Guidance and Motion Compensation in Intratympanic Steroid Injections

Intratympanic steroid injections are commonly employed in treating ear diseases, such as sudden sensorineural hearing loss or Meniere's disease through drug delivery via the middle ear. Whilst being an effective treatment, the procedure has to be performed by a trained surgeon to avoid delicate regions in the patient's anatomy and is considered painful despite the use of topical anaesthesia. In this letter we introduce a fluid-driven soft robotic system which aims at increasing patient-comfort during the injection by counteracting unwanted needle motion, reducing the cognitive load of the clinician by autonomously identifying sensitive regions in the ear and de-risking the procedure by steering the needle towards the desired injection site. A design comprising of six embedded fluidic actuators is presented, which allow for translation and rotation of the needle as well as adaptive stiffening in the coupling between needle and ear canal. The system's steering-capabilities are investigated and the differential kinematics derived to demonstrate trajectory tracking in Cartesian space. A vision system is developed which enables tracking of anatomical landmarks on the tympanic membrane and thus locating the desired needle insertion site. The integrated system shows the ability to provide a safe guide for the inserted needle towards a desired target direction while significantly reducing needle motion. The proposed tracking algorithm is able to identify the desired needle insertion site and could be employed to avoid delicate anatomical regions

Autonomous control of an ultrasound probe for intra-operative ultrasonography using vision-based shape sensing of pneumatically attachable flexible rails

Purpose: In robotic-assisted minimally invasive surgery, surgeons often use intra-operative ultrasound to visualise endophytic structures and localise resection margins. This must be performed by a highly skilled surgeon. Automating this subtask may reduce the cognitive load for the surgeon and improve patient outcomes. Methods: We demonstrate vision-based shape sensing of the pneumatically attachable flexible (PAF) rail by using colour-dependent image segmentation. The shape-sensing framework is evaluated on known curves ranging from r=30 to r=110 mm, replicating curvatures in a human kidney. The shape sensing is then used to inform path planning of a collaborative robot arm paired with an intra-operative ultrasound probe. We execute 15 autonomous ultrasound scans of a tumour-embedded kidney phantom and retrieve viable ultrasound images, as well as seven freehand ultrasound scans for comparison. Results: The vision-based sensor is shown to have comparable sensing accuracy with FBGS-based systems. We find the RMSE of the vision-based shape sensing of the PAF rail compared with ground truth to be 0.4975±0.4169 mm. The ultrasound images acquired by the robot and by the human were evaluated by two independent clinicians. The median score across all criteria for both readers was ‘3—good’ for human and ‘4—very good’ for robot. Conclusion: We have proposed a framework for autonomous intra-operative US scanning using vision-based shape sensing to inform path planning. Ultrasound images were evaluated by clinicians for sharpness of image, clarity of structures visible, and contrast of solid and fluid areas. Clinicians evaluated that robot-acquired images were superior to human-acquired images in all metrics. Future work will translate the framework to a da Vinci surgical robot

Localization of Interaction using Fibre-Optic Shape Sensing in Soft-Robotic Surgery Tools

Minimally invasive surgery requires real-time tool tracking to guide the surgeon where depth perception and visual occlusion present navigational challenges. Although vision-based and external sensor-based tracking methods exist, fibre-optic sensing can overcome their limitations as they can be integrated directly into the device, are biocompatible, small, robust and geometrically versatile. In this paper, we integrate a fibre Bragg grating-based shape sensor into a soft robotic device. The soft robot is the pneumatically attachable flexible (PAF) rail designed to act as a soft interface between manipulation tools and intra-operative imaging devices. We demonstrate that the shape sensing fibre can detect the location of the tools paired with the PAF rail, by exploiting the change in curvature sensed by the fibre when a strain is applied to it. We then validate this with a series of grasping tasks and continuous US swipes, using the system to detect in real-time the location of the tools interacting with the PAF rail. The overall location-sensing accuracy of the system is 64.6%, with a margin of error between predicted location and actual location of 3.75 mm

Evaluation of A Novel Organ Perfusion Research Platform

This paper presents a novel, low cost, organ perfusion machine designed for use in research. The modular and versatile nature of the system allows for additional sensing equipment to be added or adapted for specific use. Here we introduce the system and present its preliminary evaluation by assessing its ability to maintain a predetermined input pressure. A proportional-integral-derivative (PID) controller was implemented and tested on a porcine liver to maintain input pressure to the hepatic artery and compared to bench tests. The results confirmed the effectiveness of the controller for maintaining input through the hepatic artery (HA) in a timely manner. Clinical Relevance-Machine Perfusion (MP) is proving to be an invaluable adjunct in clinical practice. With its ongoing success in the transplant arena, we propose MP for use in research. A cost-effective, versatile system that can be modified for specific research use to test new pharmacological therapies, imaging techniques or develop simulation training would be beneficial

Track-Guided Ultrasound Scanning for Tumour Margins Outlining in Robot-Assisted Partial Nephrectomy

Robot-Assisted Partial Nephrectomy (RAPN) is a medical procedure in which part of a kidney is removed, typically because of the presence of a tumour. RAPN is the second most diffused robotically assisted surgical procedure worldwide after prostatectomy [1]. The advantages of this robot-assisted procedure are detailed in [2], and in [3] it is argued that RAPN can be used in place of open surgery or total nephrectomy in some complex renal tumour cases. The RAPN procedure is thoroughly described in [4]. Methods used for the identification of the tumour include pre-operative Computer Tomography (CT) scans, Magnetic Resonance (MR) imaging and intraoperative Ultrasound (US) scans. The use of drop-in US probes for RAPN procedures is widely recognized as the golden standard for the intraoperative detection and margins outlining of the mass targeted. In [5] the authors show that the use of US dropin probes guided by robotic laparoscopic tools rather than standard laparoscopic tool is beneficial for the surgeon as it significantly increases the dexterity, hence, the field of view of the system

Comparison Between the PAF Rail and Surgical Instruments for Organ Manipulation in Laparoscopic and Robotic Surgery: A Randomised Cross-Over Usability Study

This study evaluates the usability and workload associated with the pneumatically attachable flexible (PAF) rail, a soft robotic device designed for safer organ manipulation and retraction during robotic-assisted partial nephrectomy (RAPN) and other laparoscopic procedures. Fourteen expert robotic and laparoscopic surgeons performed a simulated surgical retraction task using the PAF rail and standard surgical instruments. Usability was assessed using the System Usability Scale (SUS), and workload was measured with the NASA-TLX. Qualitative feedback was also collected to explore surgeon perceptions, and analysed thematically. Histopathological analysis was conducted to assess tissue integrity following instrument interaction. The PAF rail achieved SUS scores exceeding the good usability threshold, particularly among urology surgeons. However, its use was associated with increased cognitive load and longer task completion times, especially for less experienced surgeons. Histopathological analysis showed no additional tissue damage from the PAF rail compared to existing instruments. This study demonstrates that the PAF rail has potential as a safe and effective method for organ manipulation and retraction, achieving good usability and showing no additional tissue damage compared to existing instruments