Waseda University · Engineering
Professor Ryosuke Tsumura's research lab specializes in medical robotics and minimally invasive needle interventions, focusing on optimizing needle insertion techniques for accurate and safe percutaneous procedures. The lab develops advanced preoperative path planning models that minimize needle deflection in multi-layered soft tissues by considering insertion angles, tissue properties, and mechanical interactions. Key research directions include rotational and vibrational needle insertion strategies to reduce deflection and tissue damage, with applications in challenging anatomical regions such as the lower abdomen. The lab also explores robotic systems for autonomous medical tasks, such as remote auscultation, integrating force control and real-time feedback.
Figures are computed from collected data and may differ slightly.
Fine needle deflection is a problem encountered during insertion into a soft tissue. Although an axial rotational insertion is an effective approach for minimizing this problem, needle deflection still depends on the insertion angle with respect to the tissue boundary. Since the human body consists of multi-layered tissues of various shapes and mechanical properties, preoperative planning of an optimal path is a key factor for achieving a successful insertion. In this paper, we propose an optimi
Needles used in percutaneous insertion must be as thin as possible to minimize invasiveness. However, using extra-thin needles with a diameter less than 25G (0.53 mm diameter) can cause needle deflection. Needle deflection can be minimized by insertion with axial rotation along the needle shaft; this rotation is also useful for steering the insertion direction of the needle tip. However, although high rotation speeds may decrease needle deflection, this may increase tissue damage. Therefore, the
Because fine needles can easily be deflected, accurate needle insertion is often difficult. Lower abdominal insertion is particularly difficult because of less imaging feedback; thus, an approach for allowing a straight insertion path by minimizing deflection is beneficial in cases of lower abdominal insertion. Although insertion with axial rotation can minimize deflection, the rotational insertion may cause tissue damage. Therefore, we established a novel insertion method for minimizing both de
Fine needles can easily be deflected, making accurate needle insertion into a tumor difficult. In particular, it is difficult to insert the needle into a tumor in the lower abdomen because the needle has to pass through various tissues. Therefore, for lower abdominal needle insertion, we intend to develop a planning method for the optimal insertion path to minimize the deflection based on computed tomography images. In this letter, we analyze the deflection while performing needle insertion with
The developed robotic platform enables the estimation of the landing positions and handling the stethoscope while maintaining the contact force, which promises the potential of automatic remote auscultation.
Ultrasound (US) imaging is a first-line medical imaging modality for detecting thyroid cancer; however, it suffers from operator-dependent variability in image quality and diagnostic accuracy. To address this issue, various robotic US systems have been proposed to assist in thyroid US examinations. Nevertheless, ensuring an appropriate contact force that balances image quality and patient safety during robotic thyroid US scanning remains a challenge. Thyroid US procedures require physicians to b
The proposed method can decrease fine needle deflections in the lower abdomen, which has the potential for accurate and safety procedures without real-time CT imaging.
Recently, in the United States as well as other countries, a shortage of obstetrician and gynecologist (ob-gyns) has grown seriously. The obstetrics and gynecology have a high burnout rate compared to other medical specialties because of increased workloads and competing for administrative demands. Then, there is a demand for assisting the procedure of prenatal care, especially ultrasonography. Although several robotic-assisted ultrasound imaging platforms have been developed, there were few pla
Cancer vaccine therapy is a novel treatment method which uses an extra-fine (0.53 mm in diameter (25 G)) needle to deliver a tumor-specific vaccine directly into a tumor. This method is expected to deliver an effective treatment with few side effects. However, the procedure is very difficult to perform because of needle deflection. We intend to develop a needle insertion robot to combat this deflection and deliver the vaccine successfully. The key features of the robot were developed to minimize
Accurate insertion of fine needles is difficult due to needle deflection. Needle deflection in the lower abdomen is particularly complex, as the needle has to pass through various tissues. As the area of the bowel is dominant in lower abdominal insertion, it is important to analyze the deflection during bowel insertion and to control the needle to minimize deflection. Few studies have focused on bowel insertion. We performed a fundamental deflection analysis of needle insertion in the bowel. Mor
Current standard workflows of ultrasound (US)-guided needle insertion require physicians to use their both hands: holding the US probe to locate interested areas with the non-dominant hand and the needle with the dominant hand. This is due to the separation of functionalities for localization and needle insertion. This requirement does not only make the procedure cumbersome, but also limits the reliability of guidance given that the positional relationship between the needle and US images is unk
The conventional transrectal ultrasound (TRUS) probe for transperineal needle insertion is typically a sagittal viewing linear array or combined with another transverse curvilinear array. Physicians are required to manually move and rotate the probe back and forth to determine the needle trajectory or to render 3D volume. For the hands-free 3D imaging guidance of transperineal needle insertion, this paper proposes a reflector-based 3D TRUS imaging probe. The proposed probe is enabled by motorizi
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