Ergonomics in handheld and robot-assisted camera control: a randomized controlled trial.

BACKGROUND: Laparoscopic surgery potentially increases the physical burden to operating theater personnel and can cause physical discomfort. This study aims to evaluate if a robotic camera holder (AutoLap™ system) can improve ergonomics for the surgeon and the camera assistant during laparoscopic procedures. METHODS: A total of thirty cases were included and randomized (15 AutoLap™, 15 control). Five types of surgery were included: right hemicolectomy, fundoplication, sigmoid resection, rectopexy, and low anterior resection. The posture of the surgeon and assistant was photographed during predefined steps of the procedure. MATLAB was used to calculate angles relevant for the RULA score. The RULA score is a validated method to evaluate body posture, force and repetition of the upper extremities. Two investigators assessed the RULA score independently. Three subjective questionnaires (SMEQ, NASA TLX, and LED) were used to assess mental and physical discomfort. RESULTS: No differences in patient characteristics were observed. Sixteen fundoplications, seven right hemicolectomies, five sigmoid resections, one rectopexy, and one low anterior resection were included. The mean RULA score of the surgeon was comparable in both groups, 2.58 (AutoLap™) versus 2.72 (control). The mean RULA score of the assistant was significantly different in both groups, with 2.55 (AutoLap™) versus 3.70 (control) (p = 0.001). The inter-observer variability (ICC) was excellent with 0.93 (surgeon) and 0.97 (assistant). The questionnaires showed a significant difference in physical discomfort for the assistant. The LED and SMEQ score were significantly lower in the robotic group. The NASA TLX demonstrated a significant reduction in scores in all domains when using robotics with the exception of the mental domain. CONCLUSION: Use of the AutoLap™ system shows improvement in ergonomics and posture of the first assistant, and ergonomics of the surgeon are not affected. Furthermore, the subjective work load is significantly reduced by using a robotic camera holder. TRIAL REGISTRATION NUMBER: NCT0339960, https://clinicaltrials.gov/ct2/show/study/NCT03339960?term=autolap&rank=5 .

Image-based laparoscopic camera steering versus conventional steering: a comparison study.

In the last 2 decades, multiple robotic camera holders have been developed to improve camera steering during laparoscopic surgery. A new image-based steering method has been developed for more intuitive camera control. In this article, the efficiency and user experience of image-based steering were compared to conventional steering methods. Four participants (two senior surgical registrars, one junior surgical registrar and a technical medicine student) were enrolled in this study. All participants performed multiple camera steering exercises with three different steering modalities in randomized order: image-based, joystick and manual camera steering. Steering of the laparoscope was evaluated by execution time and with the SMEQ and NASA-TLX questionnaires to analyze user experience. A total of 267 camera steering exercises were performed. The analyzed data showed a significantly shorter execution time for manual camera steering compared to image-based robotic steering (p = 0.001) and joystick robotic steering (p = 0.001). The participants reported the lowest user experience with joystick camera steering. The results of the questionnaires showed no significant difference in all subscales of user experience for image-based and manual camera steering. Manual camera steering resulted in significantly higher perceived physiological workload scores (M = 30.0, IQR = 27.5) compared to image-based (M = 10, IQR = 5.0) and joystick camera steering (M = 15.0, IQR = 10.0). Manual control of the laparoscope remains the fastest steering method at the expense of a high physical workload. Using image-based camera steering is a viable alternative to the current joystick control of robotic camera holders, as it improves speed and user experience. The study results suggest that optimisation of robotic camera steering with algorithms based on image analysis is a promising technology.

Advancing intraoperative magnetic tracing using 3D freehand magnetic particle imaging.

PURPOSE: Sentinel lymph node biopsy is a routine procedure for nodal staging in penile cancer. Most commonly, this procedure is guided by radioactive tracers, providing various forms of preoperative and intraoperative guidance. This is further extended with fluorescence imaging using hybrid radioactive-fluorescence tracers. Alternatively, a magnetic-based approach has become available using superparamagnetic iron-oxide nanoparticles (SPIONs). This study investigates a novel freehand magnetic particle imaging and navigation modality (fhMPI) for intraoperative localization, along with a hybrid approach, combining magnetic and fluorescence guidance. MATERIALS AND METHODS: The fhMPI set-up was built with a surgical navigation device, optical tracking system and magnetometer probe. A dedicated reconstruction software based on a look-up-table method was used to reconstruct a superficial 3D volume of the SPION distribution in tissue. For fluorescence guidance, indocyanine green (ICG) was added to the SPIONs. The fhMPI modality was characterized in phantoms, ex vivo human skin and in vivo porcine surgery. RESULTS: Phantom and human skin explants illustrated that the current fhMPI modality had a sensitivity of 2.2 × 10-2 mg/mL SPIONs, a resolving power of at least 7 mm and a depth penetration up to 1.5 cm. Evaluation during porcine surgery showed that fhMPI allowed for an augmented reality image overlay of the tracer distribution in tissue, as well as 3D virtual navigation. Besides, using the hybrid approach, fluorescence imaging provided a visual confirmation of localized nodes. CONCLUSION: fhMPI is feasible in vivo, providing 3D imaging and navigation for magnetic nanoparticles in the operating room, expanding the guidance possibilities during magnetic sentinel lymph node procedures. Furthermore, the integration of ICG provides the ability to visually refine and confirm correct localization. Further clinical evaluation should verify these findings in human patients as well.

Laparoscopic Probe for Sentinel Lymph Node Harvesting Using Magnetic Nanoparticles.

OBJECTIVE: Sentinel lymph node harvesting is an essential step in the surgical treatment of a growing number of malignancies. Various techniques are available to facilitate this purpose. The present study reports a new laparoscopic technique for lymph node harvesting using magnetic nanoparticles containing a superparamagnetic iron-oxide core and dextran coating. This study assesses the clinical relevance of the prototype and provides input for further technological development on the way to clinical implementation. METHODS: A laparoscopic differential magnetometer prototype was built, utilizing a nonlinear detection principle (differential magnetometry) for magnetic identification of lymph nodes. The iron content sensitivity, depth & spatial sensitivity, and angular sensitivity were analyzed to investigate clinical options. RESULTS: The minimum detectable amount of iron was 9.8 µg at a distance of 1 mm. The detection depth was 5, 8, and 10 mm for samples containing 126, 252, and 504 µg iron, respectively. The maximum lateral detection distance was 5, 7, and 8 mm for samples containing 126, 252, and 504 µg iron, respectively. A sample containing 504 µg iron was detectable at all angulations assessed (0°, 30°, 60° and 90°). CONCLUSION: The laparoscopic differential magnetometer demonstrates promising results for further investigation and development towards laparoscopic lymph node harvesting using magnetic nanoparticles. SIGNIFICANCE: The laparoscopic differential magnetometer facilitates a novel method for sentinel lymph node harvesting, which helps to determine prognosis and treatment of cancer patients.