Increased access sheath diameter does not improve flow when the working channel of a flexible ureteroscope is occupied. Our proposed configuration of a ureteral access catheter placed inside or alongside the access sheath provides by far the highest flow rates without a rise in the intrarenal pressure.

Nowadays Robotic assisted Minimally Invasive Surgeries (R-MIS) are the elective procedures for treating highly accurate and scarcely invasive pathologies, thanks to their ability to empower surgeons' dexterity and skills. The research on new Multi-Robots Surgery (MRS) platform is cardinal to the development of a new SARAS surgical robotic platform, which aims at carrying out autonomously the assistants tasks during R-MIS procedures. In this work, we will present the SARAS MRS platform validation protocol, framed in order to assess: (i) its technical performances in purely dexterity exercises, and (ii) its functional performances. The results obtained show a prototype able to put the users in the condition of accomplishing the tasks Manuscript

This paper presents an intraoperative MRI-guided, patient-mounted robotic system for shoulder arthrography procedures in pediatric patients. The robot is designed to be compact and lightweight and is constructed with nonmagnetic materials for MRI safety. Our goal is to transform the current two-step arthrography procedure (CT/x-ray-guided needle insertion followed by diagnostic MRI) into a streamlined single-step ionizing radiation-free procedure under MRI guidance. The MR-conditional robot was evaluated in a Thiel embalmed cadaver study and healthy volunteer studies. The robot was attached to the shoulder using straps and ten locations in the shoulder joint space were selected as targets. For the first target, contrast agent (saline) was injected to complete the clinical workflow. After each targeting attempt, a confirmation scan was acquired to analyze the needle placement accuracy. During the volunteer studies, a more comfortable and ergonomic shoulder brace was used, and the complete clinical workflow was followed to measure the total procedure time. In the cadaver study, the needle was successfully placed in the shoulder joint space in all the targeting attempts with translational and rotational accuracy of 2.07 ± 1.22 mm and 1.46 ± 1.06 degrees, respectively. The total time for the entire procedure was 94 min and the average time for each targeting attempt was 20 min in the cadaver study, while the average time for the entire workflow for the volunteer studies was 36 min. No image quality degradation due to the presence of the robot was detected. This Thiel-embalmed cadaver study along with the clinical workflow studies on human volunteers demonstrated the feasibility of using an MR-conditional, patient-mounted robotic system for MRI-guided shoulder arthrography procedure. Future work will be focused on moving the technology to clinical practice.

Hepatic resection for large solitary tumours but particularly for hepatocellular cancer (HCC) produces the best palliation, improves the prognosis, and offers the only chance of cure. Nevertheless, resectional surgery can be difficult due to the large size of many of these lesions, and underlying cirrhosis often makes it essential to preserve the maximum amount of parenchyma. Pedunculated or dependent hepatic tumours represent a rare subgroup of hepatic tumours: a favourable group for resection in most cases because of their anatomical configuration and their morphological characteristic to be often encapsulated. The aim of this study was to review our experience of 20 patients referred from October 1986 to April 1995 with pedunculated or dependent hepatic tumours considered suitable for resection. This group consisted of 14 patients with HCC, 3 with colorectal metastases, and 3 patients with focal nodular hyperplasias. Fifteen of these patients underwent laparotomy, and 13 tumours were resectable. There was no operative or 30-day mortality. From the HCC-oper-ated group 2 patients remain alive for 73 and 60 months, respectively, without tumour recurrence. In our series we found a possible relationship between survival and the different histomorphological findings in the transition zone between the tumour and the liver tissue. Pedunculated lesions other than HCC have not previously been described but were found in 3 patients with colorectal metastases and in 3 patients with focal nodular hyperplasias. It is important that this favourable anatomical configuration is recognized when assessing patients with large hepatic tumoral lesions because it offers a great chance for tumoural resection.

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