Current Issue : July-September Volume : 2026 Issue Number : 3 Articles : 5 Articles
Lower-limb exoskeletons require accurate dynamic models to achieve stable and compliant human–robot interactions. However, least-squares-based identification often relies on demanding experiments and may yield limited accuracy for exoskeletons with non-standard structures and actuator-induced uncertainties. This paper proposes a two-stage dynamic parameter identification method that integrates recursive least squares (RLS) and a genetic algorithm (GA), denoted as RLS-GA. RLS is first executed offline to estimate the variation ranges of the inertial parameter vector and to construct a finite, physically meaningful search space. GA then refines the parameters within these bounds by minimizing the regression residual norm. Experiments on a hip exoskeleton show that RLS-GA achieves higher identification accuracy than LS and unconstrained GA, while converging faster than GA under identical conditions....
Introduction: Minimally invasive pancreatoduodenectomy (MIPD), including laparoscopic (LPD) and robotic approaches (RPD), has gained increasing attention as an alternative to open pancreatoduodenectomy (OPD). Despite rapid technological progress, concerns persist regarding safety, reproducibility, and oncological adequacy. The publication of randomized controlled trials (RCTs) provides essential high-level evidence to reassess the true benefits and limitations of MIPD. Methods: This narrative review synthesizes all available RCTs comparing LPD and RPD with OPD. Major domains evaluated include mortality, major morbidity, intraoperative parameters, postoperative recovery, oncological outcomes, conversion, costs, and the influence of surgeon experience and institutional volume. The objective is to contextualize RCT findings rather than perform a quantitative meta-analysis. Discussion: Across studies, LPD demonstrates comparable mortality and complication rates to OPD in high-volume centers, with consistent reductions intraoperative blood loss (IBL) and shorter recovery or length of stay (LOS). RPD shows more heterogeneous results: one large trial reported improved postoperative recovery, whereas the EUROPA trial identified higher rates of pancreatic fistula (POPF) and delayed gastric emptying (DGE) alongside significantly increased costs. Both LPD and RPD achieve oncological outcomes equivalent to OPD, and 3-year survival data confirm the long-term non-inferiority of LPD. However, operative time remains longer for all minimally invasive approaches, and conversion persists as a marker of technical difficulty and incomplete learning curve. Conclusions: Current RCT evidence indicates that MIPD is safe, feasible, and oncologically sound only when performed by surgeons who have surpassed the demanding learning curve within specialized, high-volume centers. The benefits, mainly reduced IBL and faster recovery, must be weighed against longer operative times, conversion risks, and substantially higher costs for RPD. MIPD should therefore be considered an advanced option rather than a universal standard, and its broader implementation requires structured training pathways, appropriate patient selection, and institutional readiness....
Computed tomography (CT) images are stored at a 12-bit depth. However, many deep learning libraries and pre-trained models are designed for 8-bit images, requiring an intermediate compression step before restoring the original 12-bit physical range. This process causes information loss and can compromise image reliability. This study investigated the impact of two CT resampling methods (8-bit compression; 12-bit decompression) on dose calculation and image quality. Ten total marrow and lymphoid irradiation patients were selected. CT scans were resampled using linear and non-linear look-up tables (l_LUT/nl_LUT). Original and resampled CTs were evaluated considering: (i) Hounsfield unit (HU) root mean squared error (RMSE); (ii) dose-volume histogram (DVH) statistics for target volume and several organs; (iii) 3D gamma passing rate (GPR) with a 1%/1.25 mm criterion; (iv) lymph nodes contouring and diagnostic quality (scale 1–5). The RMSE for l_LUT vs. nl_LUT was 7 ± 1 vs. 10 ± 1 HU. Maximum differences in DVH statistics were 0.4%, with a 3D-GPR = 100% for all cases. CTs resampled with l_LUT exhibited evident brain pixelation (score = 1), whereas nl_LUT matched the original CT quality (score = 4). Both LUTs were acceptable for lymph nodes delineation. The nl_LUT optimized the CT resampling process, providing a more efficient method for possible deep learning applications in synthetic CT generation....
Background: The learning curve for robotic low anterior resection (LAR) utilizing the modern da Vinci Xi system within a high-volume, standardized environment remains poorly defined. This study aimed to delineate the technical proficiency of a single highvolume surgeon using the Xi platform. Methods: A retrospective analysis of 95 consecutive patients undergoing robotic LAR for primary rectal malignancy between 2020 and 2023 was conducted. All procedures were performed by a single surgeon using the da Vinci Xi system under a standardized ERAS protocol. Cumulative sum (CUSUM) analysis of operative time was used to define learning phases. Results: CUSUM analysis identified a proficiency inflection point after 16 cases. Median docking time significantly decreased in the proficiency phase (14.5 vs. 10.0 min, p < 0.01). Notably, zero conversions to open surgery occurred throughout the series. Comparative analysis revealed comparable overall complication rates (0.0% vs. 13.9%, p = 0.201) and postoperative length of stay between phases. Short-term oncological quality, including lymph node yield and circumferential resection margins, remained satisfactory in both groups. Technical precision, reflected by consistently low robotic stapler firings (median 2.0), was maintained from the outset. Conclusions: Technical proficiency in robotic LAR using the da Vinci Xi system was rapidly achieved after approximately 16 cases in this high-volume standardized setting. This accelerated learning curve was not associated with compromised perioperative safety or oncological outcomes....
Introduction: Lung cancer is a leading cause of cancer-related deaths globally, with approximately 1.5 million new peripheral pulmonary lesions (PPLs) detected annually in the United States. Robotic-assisted bronchoscopy (RAB) has emerged as a promising technology, with two platforms initially approved, the Monarch platform (Auris Health Inc, Redwood City, CA, USA) and the Ion Endoluminal System (Intuitive Surgical, Sunnyvale, CA, USA), offering improved stability and distal airway visualization. As RAB adoption increases, there is a critical need for comparative effectiveness data of these systems to guide clinical decision-making and institutional investments. This study aims to compare the diagnostic yield and safety profiles of the Ion and Monarch RAB platforms after introduction at a single institution. Methods: We conducted a retrospective chart review of patients undergoing RAB in the first six months following the introduction of each platform. Demographic and radiographic data were collected. Diagnostic yield was defined as obtaining a malignant or specific benign diagnosis from bronchoscopy. Results: The study included 56 Ion and 36 Monarch procedures. Diagnostic yield was similar between Ion (75%) and Monarch (72%) groups (p = 0.8), with an adjusted odds ratio 0.89 (95% CI 0.30–2.72). Complications were low, with one pneumothorax occurring in each group. Conclusions: Early adoption and use of both RAB platforms suggests comparable diagnostic yields and safety profiles in our limited sample size. Larger studies including standardized anesthesia protocol and systematic use of real-time imaging are needed for further evaluation and comparative analysis....
Loading....