216 research outputs found
Extraocular muscle sampled volume in Graves' orbitopathy using 3-T fast spin-echo MRI with iterative decomposition of water and fat sequences
Abstract
Background: Current magnetic resonance imaging (MRI) techniques for measuring extraocular muscle (EOM) volume
enlargement are not ideally suited for routine follow-up of Graves’ ophthalmopathy (GO) because the difficulty of
segmenting the muscles at the tendon insertion complicates and lengthens the study protocol.
Purpose: To measure the EOM sampled volume (SV) and assess its correlation with proptosis.
Material and Methods: A total of 37 patients with newly diagnosed GO underwent 3-T MRI scanning with iterative
decomposition of water and fat (IDEAL) sequences with and without contrast enhancement. In each patient, the three
largest contiguous coronal cross-sectional areas (CSA) on the EOM slices were segmented using a polygon selection tool
and then summed to compute the EOM-SV. Proptosis was evaluated with the Hertel index (HI). The relationships
between the HI value and EOM-SV and between HI and EOM-CSA were compared and assessed with Pearson’s correlation
coefficient and the univariate regression coefficient. Inter-observer and intra-observer variability were
calculated.
Results: HI showed a stronger correlation with EOM-SV (P<0.001; rÂĽ0.712, r2ÂĽ0.507) than with EOM-CSA
(P<0.001; rÂĽ0.645 and r2ÂĽ0.329). The intraclass correlation coefficient indicated that the inter-observer agreement
was high (0.998). The standard deviation between repeated measurements was 1.9–5.3%.
Conclusion: IDEAL sequences allow for the measurement EOM-SV both on non-contrast and contrast-enhanced scans.
EOM-SV predicts proptosis more accurately than does EOM-CSA. The measurement of EOM-SV is practical and
reproducible. EOM-SV changes of 3.5–8.3% can be assumed to reflect true volume changes
The biocalcarenite stone of Agrigento (Italy): Preliminary investigations of compatible nanolime treatments
Nanolime is a promising consolidant for the conservation of most historic structures thanks to its high compatibility with carbonate-based substrates. Nanolime can recover the superficial cohesion of deteriorated surfaces thanks to its potential to complete the carbonation process, recreating a thin network of new cementing calcium carbonate. In this paper, the nanolime was produced by an innovative, time and energy-saving and scalable method, and its efficacy was tested preliminarily on biocalcarenite stones from Agrigento. The stones characterization as well as the treatment effectiveness, in terms of protection against water and superficial consolidation, was investigated by several techniques such as X-ray fluorescence, X-ray diffraction, scotch tape test, water absorption by capillarity, mercury intrusion porosimetry, drilling resistance measurement system and colorimeter. Investigations showed that nanolime could guarantee a complete transformation in pure calcite together with a superficial consolidation and a reduction in water absorption
Measuring High-Order Interactions in Rhythmic Processes through Multivariate Spectral Information Decomposition
Many complex systems in physics, biology and engineering are modeled as dynamical networks and described using multivariate time series analysis. Recent developments have shown that the emergent dynamics of a network system are significantly affected by interactions involving multiple network nodes which cannot be described using pairwise links. While these higher-order interactions can be probed using information-theoretic measures, a rigorous framework to describe them in the frequency domain is still lacking. This work presents an approach for the spectral decomposition of multivariate information measures, capable of identifying higher-order synergistic and redundant interactions between oscillatory processes. We show theoretically that synergy and redundancy can coexist at different frequencies among the output signals of a network system and can be detected only using the proposed spectral method. To demonstrate the broad applicability of the framework, we provide parametric and non-parametric data-efficient estimators for the spectral information measures, and employ them to describe multivariate interactions in three complex systems producing rich oscillatory dynamics, namely the human brain, a ring of electronic oscillators, and the global climate system. In these systems, we show that the use of our framework for the spectral decomposition of information measures reveals multivariate and higher-order interactions not detectable in the time domain. Our results are exemplary of how the frequency-specific analysis of multivariate dynamics can aid the implementation of assessment and control strategies in realworld network systems
Design of a Novel Long-Reach Cable-Driven Hyper-Redundant Snake-like Manipulator for Inspection and Maintenance
Robotic inspection and maintenance are gaining importance due to the number of different scenarios in which robots can operate. The use of robotic systems to accomplish such tasks has deep implications in terms of safety for human workers and can significantly extend the life of infrastructures and industrial facilities. In this context, long-reach cable-driven hyper-redundant robots can be employed to inspect areas that are difficult to reach and hazardous environments such as tanks and vessels. This paper presents a novel long-reach cable-driven hyper-redundant robot called SLIM (Snake-Like manipulator for Inspection and Maintenance). SLIM consists of a robotic arm, a pan and tilt mechanism as end-effector, and an actuation box that can rotate and around which the arm can wrap. The robot has a total of 15 degrees of freedom and, therefore, for the task of positioning the tool centre point in a bi-dimensional Cartesian space with a specific attitude, it has 10 degrees of redundancy. The robot is designed to operate in harsh environments and high temperatures and can deploy itself up to about 4.8 m. This paper presents the requirements that drove the design of the robot, the main aspects of the mechanical and electronic systems, the control strategy, and the results of preliminary experimental tests performed with a physical prototype to evaluate the robot performances
Transanal hemorrhoidal dearterialization (THD) for hemorrhoidal disease: An Italian single-institution 5-year experience analysis and updated literature review
Background: Hemorrhoidal disease is a highly prevalent, chronic disorder that usually compromise patients' quality of life. Despite recent advances in pharmacologic and surgical therapeutic options, a clear treatment "gold standard" is lacking. Our aim is to analyze the outcomes following Transanal Hemorrhoidal Dearterialization (THD) procedure. MethodsPatients who failed conservative treatment and underwent THD Doppler between 2017 and 2021 were enrolled. Follow-up interviews (consisting of clinical examination, Visual Analog Scale for pain-VAS, Vaizey incontinence score, Hemorrhoid Severity Score) were administered 1 week, 2 weeks, 1 month and 6 months after surgery. ResultsForty-seven out of 75 patients were male, and the mean age was 50 (+/- 17.9) years. Hemorrhoids were classified as Goligher's degree II in 25 cases, III in 40 and IV, simple irreducible without ischemic changes, in 10. The mean operative time was 35 (28-60) minutes, and most procedures were performed with epidural anesthesia (80%). No intraoperative complications occurred, and 73 patients (97.3%) were discharged within post-operative day 1. Early post-operative pain and bleeding occurred in 37.3% and 8% of patients, respectively. No patients experienced anal incontinence and severe symptoms at 6 months after surgery. The overall success rate was 97.3%. ConclusionsTHD is safe and effective in hemorrhoidal disease at degree II if bleeding, III, and IV without ischemic changes, both as a first intervention and on recurrence. Physician and patient need to understand each other's expectations, weight the risks and benefits, and customize the treatment
PARLOMA – A Novel Human-Robot Interaction System for Deaf-blind Remote Communication
Deaf-blindness forces people to live in isolation. Up to now there is no existing technological solution enabling two (or many) Deaf-blind persons to communicate remotely among them in tactile Sign Language (t-SL). When resorting to t-SL, Deaf-blind persons can communicate only with persons physically present in the same place, because they are required to reciprocally explore their hands to exchange messages. We present a preliminary version of PARLOMA, a novel system to enable remote communication between Deaf-blind persons. It is composed of a low-cost depth sensor as the only input device, paired with a robotic hand as output device. Essentially, any user can perform handshapes in front of the depth sensor. The system is able to recognize a set of handshapes that are sent over the web and reproduced by an anthropomorphic robotic hand. PARLOMA can work as a “telephone” for Deaf-blind people. Hence, it will dramatically improve life quality of Deaf-blind persons. PARLOMA has been designed in strict collaboration with the main Italian Deaf-blind associations, in order to include end-users in the design phase
Posterior and Para-Aortic (D2plus) Lymphadenectomy after Neoadjuvant/Conversion Therapy for Locally Advanced/Oligometastatic Gastric Cancer
Simple Summary Surgery with adequate lymphadenectomy (D2) currently represents the standard of care for resectable gastric cancer under most guidelines. However, super-extended lymphadenectomy (D2plus) may offer better locoregional control in advanced stages with a high risk of metastases to third-level nodes. In recent years, preoperative chemotherapy has become a novel issue in patients with locally advanced gastric cancer. To date, only a few studies have evaluated D2plus lymphadenectomy in patients with locally advanced or oligometastatic gastric cancer after preoperative therapy. The present study included a large series when compared with the current literature and reports limited morbidity/mortality rates and relevant survival outcomes.Abstract Super-extended (D2plus) lymphadenectomy after chemotherapy has been reported in only a few studies. This retrospective study evaluates survival outcomes in a Western cohort of locally advanced or oligometastatic gastric cancer patients who underwent D2plus lymphadenectomy after neoadjuvant chemotherapy. A total of 97 patients treated between 2010 and 2022 were included. Of these, 62 had clinical stage II/III disease, and 35 had stage IV disease. Most patients (65%) received preoperative DOC/FLOT chemotherapy. The mean number of lymph nodes harvested was 39. Pathological positive nodes in the posterior/para-aortic stations occurred in 17 (17.5%) patients. Lymphovascular invasion, ypN stage, clinical stage, and perineural invasion were predictive factors for positive posterior/para-aortic nodes. Postoperative complications occurred in 21 patients, whereas severe complications (grade III or more) occurred in 9 cases (9.3%). Mortality rate was 1%. Median overall survival (OS) was 59 months (95% CI: 13-106), with a five-year survival rate of 49 +/- 6%; the five-year OS after R0 surgery was 60 +/- 7%. In patients with positive posterior/para-aortic nodes, the median OS was 15 months (95% CI: 13-18). D2plus lymphadenectomy after chemotherapy for locally advanced or oligometastatic gastric cancer is feasible and associated with low morbidity/mortality rates. The incidence of pathological metastases in posterior/para-aortic nodes is not negligible even after systemic chemotherapy, with poor long-term survival
Weighing the benefits: Exploring the differential effects of light-weight and heavy-weight polypropylene meshes in inguinal hernia repair in a retrospective cohort study
Background: Inguinal hernia repair is a common surgical procedure, with more than 20 million cases yearly. Choice between mesh types varies in clinical practice. To compare light-weight polypropylene (LW-PP, 34-36 g/ m2) and heavy-weight polypropylene (HW-PP, 95 g/m2) meshes. Methods: Data from patients who underwent open inguinal hernia repair between 2020 and 2022. Selection criteria ensured homogeneity. Endpoints were to assess the impact of different mesh weights on overall healthrelated quality of life (HRQoL), using Short Form 36 (SF-36), and to monitor postoperative complications. Results: Two hundred patients were included in both groups. Lateral and direct hernias occurred in 60.5 % and 39.5 %. According to EHS, 31.5 %, 22.3 % and 46.2 % were classified as size 1, 2, 3. Follow-up showed similar HRQoL at 30-days, with a favorable trend towards LW-PP mesh offering fewer limitations, better comfort, and improved general health after 12-months. No difference in postoperative paresthesia, wound hematoma, and interference with daily activities. Conclusion: 1-year after surgery HRQoL evaluation highlights the non-inferiority of LW-PP. Mesh selection should be tailored, aiming at improving outcomes and postoperative comfort
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