162 research outputs found

    Long-term follow-up after surgical removal of meningioma of the inner third of the sphenoidal wing: outcome determinants and different strategies

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    Meningioma arising in the inner third of the sphenoidal wing has been well recognized since the origin of neurosurgery, yet it still poses a formidable challenge for the surgeon. Treatment strategies can be optimized through a tailored approach to surgical timing and use of a non-surgical armamentarium. The aim of this study was to evaluate the long-term effect of different strategies on progression-free survival and overall survival. We examined the clinical records of brain tumor patients to assess determinants for surgery (extent of tumor removal, postoperative complications) and for progression-free survival and overall survival in relation to timing of surgery eventually followed by stereotactic radiosurgery (SRS). The records of 60 patients were retrospectively reviewed, from preoperative assessment to a median follow-up of 104 months. All were symptomatic with prevalently visual symptoms (42.2%), large tumors (median diameter 3.44 cm), extension into the cavernous sinus (38.3%), and severe vascular involvement of one or more encased or narrowed vessels (50%). Subtotal removal was achieved in 40% of cases, mainly determined by cavernous sinus and vascular involvement; neurological complications occurred in 18.3% (persistent in 6.7% due to oculomotor and vascular injury). The overall rate of symptom improvement was 32.3% at 3 months and 49.5% at 12 months. Radiological monitoring prevented clinical progression; tumor progression occurred in 11.7% of cases. There were significant differences in progression-free survival between patients with (median 46 months) and those without (median 104 months) recurrence (p = 0.002): 12.5% after total removal, 6.2% after subtotal removal and adjuvant SRS, and 28.5% after subtotal removal and observation. The related Kaplan-Meier survival curve showed no significant difference between the three strategies. Further, disease progression after recurrence was noted in 28.6% of cases, but overall survival was not influenced by either tumor recurrence or type of treatment. Treatment failure was recorded in four cases (6.7%): one perioperative death and three later on. Surgery is the mainstay for the treatment of symptomatic meningioma and to restore neurological function; however, resectability is limited by vascular and cavernous sinus involvement. Careful postoperative monitoring prevented clinical progression and adjuvant or adjunctive SRS proved effective in tumor control. A low surgical complication rate and excellent long-term outcomes were achieved with this strategy

    Realisation of an optical pressure standard by a multi-reflection interferometric technique

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    A novel realization of an optical pressure standard, alternative to Fabry-Perot cavity-based techniques, is presented. It is based on the measurement of the refractive index of a gas through an unbalanced homodyne interferometer, designed to have one of its two arms formed by a multi reflection double mirror assembly to establish an unbalance length larger than 6 m in a compact setup. The paper illustrates the most important steps concerning its realization: the estimate of the pressure-induced deformation of the interferometer, the temperature control at millikelvin level and the measurement in vacuum of the unbalance of the interferometer. The evaluation of the uncertainty of the realized optical pressure standard currently demonstrated to fulfill the main goal of having the ability to measure pressure with a relative uncertainty of 10 ppm at 100 kPa

    CIRCULAR COMPARISON OF CONVENTIONAL PRESSURE STANDARDS USING A TRANSPORTABLE OPTICAL REFRACTOMETER: PREPARATION AND TRANSPORTATION

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    Using a transportable Fabry-PĂ©rot cavity refractometer, a circular comparison of existing primary standards at several national metrology institutes is currently underway. This paper provides information about the refractometer, the preparation for the comparison, and the transportation procedur

    Monitoring contractility in cardiac tissue with cellular resolution using biointegrated microlasers

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    Funding: This research was financially supported by the European Research Council under the European Union’s Horizon 2020 Framework Programme (FP/2014-2020)/ERC grant agreement no. 640012 (ABLASE), by EPSRC (grant no. EP/P030017/1) and by the RS Macdonald Charitable Trust. S.J.P. acknowledges funding by the Royal Society of Edinburgh (Biomedical Fellowship) and the British Heart Foundation (grant no. FS/17/9/32676). S.J.P. and G.B.R. acknowledge support from The Wellcome Trust Institutional Strategic Support Fund to the University of St Andrews (grant no. 204821/Z/16/A). M.S. acknowledges funding by the European Commission (Marie SkƂodowska-Curie Individual Fellowship, 659213) and the Royal Society (Dorothy Hodgkin Fellowship, DH160102; grant no. RGF\R1\180070).The contractility of cardiac cells is a key parameter that describes the biomechanical characteristics of the beating heart, but functional monitoring of three-dimensional cardiac tissue with single-cell resolution remains a major challenge. Here, we introduce microscopic whispering-gallery-mode lasers into cardiac cells to realize all-optical recording of transient cardiac contraction profiles with cellular resolution. The brilliant emission and high spectral sensitivity of microlasers to local changes in refractive index enable long-term tracking of individual cardiac cells, monitoring of drug administration, accurate measurements of organ-scale contractility in live zebrafish, and robust contractility sensing through hundreds of micrometres of rat heart tissue. Our study reveals changes in sarcomeric protein density as an underlying factor to cardiac contraction. More broadly, the use of novel micro- and nanoscopic lasers as non-invasive, biointegrated optical sensors brings new opportunities to monitor a wide range of physiological parameters with cellular resolution.PostprintPeer reviewe

    The unruptured intracranial aneurysm treatment score A multidisciplinary consensus

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    Objective: We endeavored to develop an unruptured intracranial aneurysm (UIA) treatment score (UIATS) model that includes and quantifies key factors involved in clinical decision-making in the management of UIAs and to assess agreement for this model among specialists in UIA management and research. Methods: An international multidisciplinary (neurosurgery, neuroradiology, neurology, clinical epidemiology) group of 69 specialists was convened to develop and validate the UIATS model using a Delphi consensus. For internal (39 panel members involved in identification of relevant features) and external validation (30 independent external reviewers), 30 selected UIA cases were used to analyze agreement with UIATS management recommendations based on a 5-point Likert scale (5 indicating strong agreement). Interrater agreement (IRA) was assessed with standardized coefficients of dispersion (v(r)*) (v(r)* 5 0 indicating excellent agreement and v(r)* = 1 indicating poor agreement). Results: The UIATS accounts for 29 key factors in UIA management. Agreement with UIATS (mean Likert scores) was 4.2 (95% confidence interval [CI] 4.1-4.3) per reviewer for both reviewer cohorts; agreement per case was 4.3 (95% CI 4.1-4.4) for panel members and 4.5 (95% CI 4.3-4.6) for external reviewers (p = 0.017). Mean Likert scores were 4.2 (95% CI 4.1-4.3) for interventional reviewers (n = 56) and 4.1 (95% CI 3.9-4.4) for noninterventional reviewers (n = 12) (p = 0.290). Overall IRA (v(r)*) for both cohorts was 0.026 (95% CI 0.019-0.033). Conclusions: This novel UIA decision guidance study captures an excellent consensus among highly informed individuals on UIA management, irrespective of their underlying specialty. Clinicians can use the UIATS as a comprehensive mechanism for indicating how a large group of specialists might manage an individual patient with a UIA.Peer reviewe

    Synopsis of Guidelines for the Clinical Management of Cerebral Cavernous Malformations: Consensus Recommendations based on Systematic Literature Review by the Angioma Alliance Scientific Advisory Board Clinical Experts Panel

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    BackgroundDespite many publications about cerebral cavernous malformations (CCMs), controversy remains regarding diagnostic and management strategies.ObjectiveTo develop guidelines for CCM management.MethodsThe Angioma Alliance ( www.angioma.org ), the patient support group in the United States advocating on behalf of patients and research in CCM, convened a multidisciplinary writing group comprising expert CCM clinicians to help summarize the existing literature related to the clinical care of CCM, focusing on 5 topics: (1) epidemiology and natural history, (2) genetic testing and counseling, (3) diagnostic criteria and radiology standards, (4) neurosurgical considerations, and (5) neurological considerations. The group reviewed literature, rated evidence, developed recommendations, and established consensus, controversies, and knowledge gaps according to a prespecified protocol.ResultsOf 1270 publications published between January 1, 1983 and September 31, 2014, we selected 98 based on methodological criteria, and identified 38 additional recent or relevant publications. Topic authors used these publications to summarize current knowledge and arrive at 23 consensus management recommendations, which we rated by class (size of effect) and level (estimate of certainty) according to the American Heart Association/American Stroke Association criteria. No recommendation was level A (because of the absence of randomized controlled trials), 11 (48%) were level B, and 12 (52%) were level C. Recommendations were class I in 8 (35%), class II in 10 (43%), and class III in 5 (22%).ConclusionCurrent evidence supports recommendations for the management of CCM, but their generally low levels and classes mandate further research to better inform clinical practice and update these recommendations. The complete recommendations document, including the criteria for selecting reference citations, a more detailed justification of the respective recommendations, and a summary of controversies and knowledge gaps, was similarly peer reviewed and is available on line www.angioma.org/CCMGuidelines
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