338 research outputs found

    Simulation and analysis of differential global positioning system for civil helicopter operations

    Get PDF
    A Differential Global Positioning System (DGPS) computer simulation was developed, to provide a versatile tool for assessing DGPS referenced civil helicopter navigation. The civil helicopter community will probably be an early user of the GPS capability because of the unique mission requirements which include offshore exploration and low altitude transport into remote areas not currently served by ground based Navaids. The Monte Carlo simulation provided a sufficiently high fidelity dynamic motion and propagation environment to enable accurate comparisons of alternative differential GPS implementations and navigation filter tradeoffs. The analyst has provided the capability to adjust most aspects of the system, the helicopter flight profile, the receiver Kalman filter, and the signal propagation environment to assess differential GPS performance and parameter sensitivities. Preliminary analysis was conducted to evaluate alternative implementations of the differential navigation algorithm in both the position and measurement domain. Results are presented to show that significant performance gains are achieved when compared with conventional GPS but that differences due to DGPS implementation techniques were small. System performance was relatively insensitive to the update rates of the error correction information

    Complications and mortality of Cushing’s disease: report on data collected over a 20-year period at a referral centre

    Get PDF
    Context: Cushing’s disease (CD) is rare condition burdened by several systemic complications correlated to higher mortality rates. The primary goal of clinicians is to achieve remission, but it is unclear if treatment can also increase life expectancy. Aim: To assess the prevalence of cortisol-related complications and mortality in a large cohort of CD patients attending a single referral centre. Materials and methods: The clinical charts of CD patients attending a referral hospital between 2001 and 2021 were reviewed. Results: 126 CD patients (median age at diagnosis 39 years) were included. At the last examination, 78/126 (61.9%) of the patients were in remission regardless of previous treatment strategies. Patients in remission showed a significant improvement in all the cardiovascular (CV) comorbidities (p < 0.05). The CV events were more frequent in older patients (p = 0.003), smokers and persistent CD groups (p < 0.05). Most of the thromboembolic (TE) and infective events occurred during active stages of the disease. The CV events were the most frequent cause of death. The standardized mortality ratio (SMR) resulted increased in persistent cases at the last follow-up (SMR 4.99, 95%CI [2.15; 9.83], p < 0.001) whilst it was not higher in those in remission (SMR 1.66, 95%CI [0.34; 4.85], p = 0.543) regardless of the timing or number of treatments carried out. A younger age at diagnosis (p = 0.005), a microadenoma (p = 0.002), and remission status at the last follow-up (p = 0.027) all increased survival. Furthermore, an elevated number of comorbidities, in particular arterial hypertension, increased mortality rates. Conclusions: Patients with active CD presented a poor survival outcome. Remission restored the patients’ life expectancy regardless of the timing or the types of treatments used to achieve it. Persistent CD-related comorbidities remained major risk factors

    Surgical Treatment of Spinal Meningiomas in the Elderly (≥75 Years): Which Factors Affect the Neurological Outcome? An International Multicentric Study of 72 Cases

    Get PDF
    (1) Background: With the increasing life expectancy in the Western world, an increasing number of old patients presents with spinal meningioma. Considering the benign nature of these tumors, the functional outcome remains of great importance, since more people reach old age in general conditions of well-being and satisfactory autonomy. (2) Methods: We conducted an international multicenter retrospective study to investigate demographic, clinical and radiological data in a population of elderly patients (≥75 years of age) undergoing surgery for SM from January 2000 to December 2020 in four European referral centers. The aim was to identify prognostic and predictive factors for a good postoperative functional outcome. (3) Results: 72 patients were included in the study. Complete tumor resection (Simpson I or II) was achieved in 67 (95.7%) cases. Intraoperative complications were reported in 7 (9.9%) patients while postoperative complications were found in 12 (16.7%). An excellent general postoperative status (McCormick I and II) was achieved in 65.3%. Overall, surgical resection had a good impact on patients’ functional outcome (86.1% either showing an improvement or maintaining a good preoperative status). Uni- and multivariate analyses found that both age and preoperative modified McCormick independently correlated with relative outcome (coeff = −0.058, p = 0.0251; coeff = 0.597, p < 0.0001) and with postoperative status (coeff = 0.058, p = 0.02507; coeff = 0.402, p = 0.00027), respectively. (4) Conclusions: Age and preoperative modified McCormick were found to be independent prognostic factors. Nevertheless, advanced age (≥75), per se, did not seem to contraindicate surgery, even in those with severe preoperative neurological deficits. The functional results sustain the need for surgical resection of SM in the elderly

    How do we estimate survival? External validation of a tool for survival estimation in patients with metastatic bone disease-decision analysis and comparison of three international patient populations.

    Get PDF
    Abstract BACKGROUND: We recently developed a clinical decision support tool, capable of estimating the likelihood of survival at 3 and 12 months following surgery for patients with operable skeletal metastases. After making it publicly available on www.PATHFx.org , we attempted to externally validate it using independent, international data. METHODS: We collected data from patients treated at 13 Italian orthopaedic oncology referral centers between 2010 and 2013, then applied to PATHFx, which generated a probability of survival at three and 12-months for each patient. We assessed accuracy using the area under the receiver-operating characteristic curve (AUC), clinical utility using Decision Curve Analysis (DCA), and compared the Italian patient data to the training set (United States) and first external validation set (Scandinavia). RESULTS: The Italian dataset contained 287 records with at least 12 months follow-up information. The AUCs for the three-month and 12-month estimates was 0.80 and 0.77, respectively. There were missing data, including the surgeon's estimate of survival that was missing in the majority of records. Physiologically, Italian patients were similar to patients in the training and first validation sets. However notable differences were observed in the proportion of those surviving three and 12-months, suggesting differences in referral patterns and perhaps indications for surgery. CONCLUSIONS: PATHFx was successfully validated in an Italian dataset containing missing data. This study demonstrates its broad applicability to European patients, even in centers with differing treatment philosophies from those previously studied

    Association between thyroid function and regorafenib efficacy in patients with relapsed wild-type IDH glioblastoma: a large multicenter study

    Get PDF
    Purpose: Regorafenib demonstrated encouraging results in recurrent glioblastoma patients. Some studies showed that changes in circulating thyroid hormones (fT3, fT4, fT3/fT4 ratio) can be considered as prognostic factors in patients with various types of tumors. We designed this study to investigate the relationship between baseline thyroid variables and outcome in IDH-wild type GBM patients who were treated with regorafenib. Methods: This multicenter retrospective study included recurrent IDH-wild-type glioblastoma patients treated with regorafenib. Only patients with baseline thyroid function values (TSH, fT3, fT4, fT3/fT4 ratio) available were evaluated. RANO criteria were used to analyze neuroradiological response. Survival curves were estimated using the Kaplan–Meier method. The relationships between baseline thyroid variables (TSH, fT3, fT4, fT3/fT4) and survival (PFS, OS) were investigated with Cox regression models. Results: From November 2015 to April 2022, 134 recurrent IDH-wildtype GBM patients were treated with regorafenib and 128 of these had information on baseline thyroid function value. Median follow-up was 8 months (IQR 4.7–14.0). Objective Response Rate was 9% and Disease Control Rate was 40.9%. Median PFS was 2.7 months (95%CI 2.2–3.6) and median OS was 10.0 months (95%CI 7.0–13.0). Lower baseline TSH value in the blood was correlated with a higher rate of disease progression to regorafenib (p = 0.04). Multivariable analyses suggested a non-linear relationship between PFS (p = 0.01) and OS (p = 0.03) with baseline fT3/fT4 ratio. Conclusion: In recurrent wild-type IDH glioblastoma patients, baseline fT3/fT4 ratio showed a non-linear relationship with survival, with different impacts across the spectrum of fT3/fT4 ratio. Moreover, baseline TSH may be a predictor of regorafenib activity

    Algoritmo terapeutico per il trattamento delle metastasi del sacro. Raccomandazioni del gruppo di studio SIOT sulle metastasi ossee

    Get PDF
    La metastasi ossea è un evento estremamente frequente nella storia naturale della patologia neoplastica maligna, preceduto per frequenza soltanto dalle sedi di localizzazione epatica e polmonare, e predilige lo scheletro assile rispetto a quello appendicolare 1 . Si stima infatti che circa il 5-10% dei pazienti oncologici sviluppi metastasi vertebrali nel corso della malattia 2 ; nel rachide, il segmento più colpito è il tratto toracico, seguito da quello lombare, cervicale e dalla giunzione lombosacrale 3 . I tumori che più frequentemente metastatizzano a livello osseo sono i carcinomi mammario, polmonare, renale, tiroideo e prostatico, mentre più raro è il riscontro di metastasi da melanoma o localizzazioni vertebrali da tumori della sistema linfoemopoietico come il linfoma 3-7. La diffusione metastatica all’osso avviene prevalentemente per via ematica, ed in rare occasioni per contiguità, soprattutto ad opera di tumori localmente aggressivi come il carcinoma del colon-retto a livello del sacro 8 9 (Fig. 1), o il tumore di Pancoast nel rachide toracico. Le metastasi sacrali sono lesioni relativamente rare; tuttavia negli ultimi anni il loro riscontro è aumentato, parallelamente all’incremento dell’aspettativa di vita dei pazienti oncologici, sottoposti a protocolli di trattamento sempre migliori 10. Ciononostante, le metastasi sacrali sono raramente diagnosticate precocemente per via della sintomatologia sfumata che caratterizza il coinvolgimento del sacro nelle fasi iniziali, ed anche alla ridotta sensibilità dell’esame radiologico convenzionale nell’individuare processi sostitutivi a tale livello 11. La valutazione e il trattamento di un paziente con metastasi sacrali richiede un approccio multidisciplinare, da effettuarsi in centri specializzati con esperienza consolidata. Le lesioni metastatiche del sacro non sono state largamente indagate in letteratura, e per il loro trattamento non sono ancora disponibili linee guida condivise, proprio per la mancanza di evidenza scientifica significativa sull’argomento. Per tale motivo, questo è stato scelto di presentare l’algoritmo terapeutico del trattamento delle metastasi del sacro nel contesto di una raccomandazione clinica, che tiene conto dell’esperienza clinica di centri di alta specializzazione sull’argomento

    A multi-parametric wearable system to monitor neck movements and respiratory frequency of computer workers

    Get PDF
    Musculoskeletal disorders are the most common form of occupational ill-health. Neck pain is one of the most prevalent musculoskeletal disorders experienced by computer workers. Wrong postural habits and non-compliance of the workstation to ergonomics guidelines are the leading causes of neck pain. These factors may also alter respiratory functions. Health and safety interventions can reduce neck pain and, more generally, the symptoms of musculoskeletal disorders and reduce the consequent economic burden. In this work, a multi-parametric wearable system based on two fiber Bragg grating sensors is proposed for monitoring neck movements and breathing activity of computer workers. The sensing elements were positioned on the neck, in the frontal and sagittal planes, to monitor: (i) flexion-extension and axial rotation repetitions, and (ii) respiratory frequency. In this pilot study, five volunteers were enrolled and performed five repetitions of both flexion-extension and axial rotation, and ten breaths of both quite breathing and tachypnea. Results showed the good performances of the proposed system in monitoring the aforementioned parameters when compared to optical reference systems. The wearable system is able to well-match the trend in time of the neck movements (both flexion-extension and axial rotation) and to estimate mean and breath-by-breath respiratory frequency values with percentage errors ≤6.09% and ≤1.90%, during quiet breathing and tachypnea, respectively

    Hip viscosupplementation under ultra-sound guidance riduces NSAID consumption in symptomatic hip osteoarthritis patients in a long follow-up. Data from Italian registry.

    Get PDF
    Introduction: Non-steroidal anti-inflammatory drugs (NSAIDs) consumption is strictly related to a high gastrointestinal and cardiovascular mortality and morbidity rate. Osteoarthritis Research Society International (OARSI) recommendations in patients with symptomatic hip or knee OA stated that NSAIDs should be used at the lowest effective dose but their long-term use should be avoided if possible. OARSI guidelines for the treatment of the hip OA include the use of viscosupplementation, which aims to restore physiological and Theological features of the synovial fluid. Objective: Aim of this multicentric, open and retrospective study is to investigate if NSAID consumption may be reduced by the use of ultrasound-guided intra-articular injection of several hyaluronic acid (HA) products in hip joint administered in patients affected by symptomatic hip OA. Materials and Methods: Patients affected by mono or bilateral symptomatic hip OA according to American Rheumatology Association (ARA) criteria, radiological OA graded II-IV (Kellgren and Lawrence) entered the study and were administered with ultrasound-guided intra-articular injection of hyaluronic acid products. As a primary endpoint, consumption of NSAIDs was evaluated by recording the number of days a month (range 0-30) the patient had used NSAID during the previous month, reported at each visit during the 24 months follow-up period. Secondary endpoints included further analysis for subgroups of patients categorized for Lequesne index score, Kellgren-Lawrence score, pain visual analogue scale (VAS) score, ultrasound pattern, age, hyaluronic acid used. Results: 2343 patients entered the study. Regarding primary endpoint, the consumption of NSAIDs was reduced of 48.2% at the third month when compared with baseline values. This sparing effect increased at 12th and 24th month with a reduction respectively of 50% and 61% in comparison to baseline values. These differences were statistically significant. Conclusions: These data point out that intraarticular hyaluronan preparations provide OA pain relief and reduce NSAIDs consumption in a large cohort of patients for a long period of follow-up. Multiple courses of viscosupplementation (vs) are required to maintain low dose of NSAID consumption over time. NSAIDs consumption is strictly related to an high gastrointestinal and cardiovascular mortality and morbidity rate, instead HA intra-articular treatment is well tolerated and is associated with a low incidence of adverse effects. For these reasons further studies evaluating cost-effectiveness and cost-utility of VS in the management of hip OA are required
    • …
    corecore