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1.
Cancer Radiother ; 28(3): 251-257, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38866650

RESUMO

PURPOSE: MRI is essential in the management of brain tumours. However, long waiting times reduce patient accessibility. Reducing acquisition time could improve access but at the cost of spatial resolution and diagnostic quality. A commercially available artificial intelligence (AI) solution, SubtleMR™, can increase the resolution of acquired images. The objective of this prospective study was to evaluate the impact of this algorithm that halves the acquisition time on the detectability of brain lesions in radiology and radiotherapy. MATERIAL AND METHODS: The T1/T2 MRI of 33 patients with brain metastases or meningiomas were analysed. Images acquired quickly have a matrix divided by two which halves the acquisition time. The visual quality and lesion detectability of the AI images were evaluated by radiologists and radiation oncologist as well as pixel intensity and lesions size. RESULTS: The subjective quality of the image is lower for the AI images compared to the reference images. However, the analysis of lesion detectability shows a specificity of 1 and a sensitivity of 0.92 and 0.77 for radiology and radiotherapy respectively. Undetected lesions on the IA image are lesions with a diameter less than 4mm and statistically low average gadolinium-enhancement contrast. CONCLUSION: It is possible to reduce MRI acquisition times by half using the commercial algorithm to restore the characteristics of the image and obtain good specificity and sensitivity for lesions with a diameter greater than 4mm.


Assuntos
Algoritmos , Inteligência Artificial , Neoplasias Encefálicas , Imageamento por Ressonância Magnética , Meningioma , Humanos , Imageamento por Ressonância Magnética/métodos , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/radioterapia , Estudos Prospectivos , Meningioma/diagnóstico por imagem , Meningioma/radioterapia , Neoplasias Meníngeas/diagnóstico por imagem , Neoplasias Meníngeas/radioterapia , Feminino , Masculino , Radioterapia (Especialidade)/métodos , Pessoa de Meia-Idade , Idoso , Fatores de Tempo , Sensibilidade e Especificidade , Adulto , Serviço Hospitalar de Radiologia
2.
Neurosci Res ; 170: 181-186, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32768417

RESUMO

Visuospatial memory (VSM) performance depends on intrinsic (biopsychosocial parameters) and extrinsic (space) factors. We aimed at characterizing the determinants of VSM performance according to space. Young healthy adults, 20 males and 41 females (23 ±â€¯3 years old), were assessed for VSM performance through a pathway learning task, in reaching (eCorsi Block Tapping task) and walking space (Virtual Walking Corsi Task). We evaluated psychosocial factors through seven questionnaires - Epworth Sleepiness Scale, Pittsburgh Sleep Quality Index, Fatigue Severity Scale, Profile of the Mood States, 2nd edition, short version, Coping Inventory for Stressful Situations, Measurement of Ambiguity Tolerance, Motives for Physical Activities Measure-Revised, mental rotation capabilities and locomotor characteristics (physical activity level through embedded trackers and the International Physical Activity Questionnaire, and gait parameters). The most explanatory biopsychosocial determinants of VSM performance were i) mental rotation capabilities and fatigue indicator in reaching space, and ii) mental rotation capabilities and physical activity level (tracked active energy expenditure only) in walking space. These results suggest that specific parameters should be preferred for the evaluation and strengthening of VSM capabilities in both reaching or walking spaces.


Assuntos
Cognição , Caminhada , Adulto , Fadiga , Feminino , Marcha , Humanos , Masculino , Adulto Jovem
3.
Cancer Radiother ; 24(8): 851-859, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33129717

RESUMO

PURPOSE: Flaps are increasingly used during reconstructive surgery of head and neck cancers to improve functional outcomes. There are no guidelines as to whether the whole flap or its anastomotic border should be included in the primary tumour target volume of postoperative radiotherapy to prevent local relapses. Relapse and toxicity rates can increase substantially if the whole flap received full dose. Our aim was to determine whether flaps were included in the primary tumour target volume and to report the patterns of relapse and toxicity. MATERIALS AND METHODS: Consecutive patients in 2014 through 2016, with or without a flap, receiving postoperative radiotherapy were selected in a retrospective monocentric control study. Flaps were homogenously delineated blind to treating radiation oncologists using a flap-specific atlas. Tumour recurrence, acute and late toxicity were evaluated using univariate and propensity score analyses. RESULTS: A hundred patients were included; 54 with a flap. Median flap volume included in the tumour volume was 80.9%. Twelve patients experienced local recurrences: six with a flap, among whom two within their flap (3.7%). Patients with flaps had larger median tumour volumes to be irradiated (25cm3 versus 58cm3, p<0.001) and higher acute/late toxicity rates (p<0.001) even after adjustment on biases (more advanced T stage, oral cavity, active smoking in patients with flaps). Locoregional recurrence and survival rates were similar between patients with/without a flap. CONCLUSION: Recurrences within a flap were rare in this series when including the whole flap body in the 60Gy-clinical target volume but inclusion of the flap in the primary tumour target volume increased toxicity. Multicentric studies are warranted.


Assuntos
Neoplasias de Cabeça e Pescoço/radioterapia , Neoplasias de Cabeça e Pescoço/cirurgia , Recidiva Local de Neoplasia , Retalhos Cirúrgicos/transplante , Adulto , Idoso , Idoso de 80 Anos ou mais , Análise de Variância , Feminino , Neoplasias de Cabeça e Pescoço/diagnóstico por imagem , Neoplasias de Cabeça e Pescoço/mortalidade , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/diagnóstico por imagem , Cuidados Pós-Operatórios/métodos , Pontuação de Propensão , Lesões por Radiação/etiologia , Procedimentos de Cirurgia Plástica/métodos , Estudos Retrospectivos
4.
Cancer Radiother ; 24(4): 340-344, 2020 Jul.
Artigo em Francês | MEDLINE | ID: mdl-32444285

RESUMO

PURPOSE: MRI is sometimes critical to optimal radiotherapy planning but may be contraindicated in increasing numbers of patients who carry an implantable cardiac device (ICD, pacemaker or defibrillator). MATERIAL AND METHODS: This literature search reviews studies of MRI in DCI patients, morbidity and procedures for the different types of ICD. RESULTS: Several retrospective studies and two recent large prospective studies have shown that the use of an ICD is not an absolute contraindication to MRI, given that specific DCI monitoring is performed under the tridisciplinary supervision of the oncologist, radiologist and cardiologist for MRI≤1.5T. The rate of major complications is less than 5% unless probe replacement is performed. When it can be anticipated, new MRI-compatible ICD can be implanted rather than conventional ICD, but probe replacement is not currently recommended. Data for MRI beyond 1.5T and in case of MRI repeatability in the context of MRI-Linac treatments are lacking. CONCLUSIONS: MRI may be performed in ICD patients, as the risk of morbidity is very low; provided that tridisciplinary evaluation is performed.


Assuntos
Desfibriladores Implantáveis , Imageamento por Ressonância Magnética , Marca-Passo Artificial , Planejamento da Radioterapia Assistida por Computador , Fatores Etários , Contraindicações de Procedimentos , Desfibriladores Implantáveis/efeitos adversos , Humanos , Imageamento por Ressonância Magnética/efeitos adversos , Marca-Passo Artificial/efeitos adversos , Estudos Prospectivos , Estudos Retrospectivos , Fatores de Tempo
5.
Cancer Radiother ; 23(8): 860-866, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31677901

RESUMO

PURPOSE: Stereotactic radiosurgery and hypofractionated stereotactic radiotherapy are standard treatments for brain metastases when they are small in size (at the most 3cm in diameter) and limited in number, in patients with controlled extracerebral disease and a good performance status. Large inoperable brain metastases usually undergo hypofractionated stereotactic radiotherapy while haemorrhagic brain metastases have often been contraindicated for both stereotactic radiosurgery or hypofractionated stereotactic radiotherapy. The objective of this retrospective study was to assess a six 6Gy-fractions hypofractionated stereotactic radiotherapy scheme in use at our institution for haemorrhagic brain metastases, large brain metastases (size greater than 15cm3) or brain metastases located next to critical structures. MATERIAL AND METHODS: Patients with brain metastases treated with the 6×6Gy scheme since 2012 to 2016 were included. Haemorrhagic brain metastases were defined by usual criteria on CT scan and MRI. Efficacy, acute and late toxicity were evaluated. RESULTS: Sixty-two patients presenting 92 brain metastases were included (32 haemorrhagic brain metastases). Median follow up was 10.1 months. One-year local control rate for haemorrhagic brain metastases, large brain metastases, or brain metastases next to critical structures were 90.7%, 73% and 86.7% respectively. Corresponding overall survival rates were 61.2%, 32% and 37.8%, respectively. Haemorrhagic complications occurred in 5.3% of patients (N=5), including two cases of brain metastases with pretreatment haemorrhagic signal. Tolerance was good with only one grade 3 acute toxicity. CONCLUSION: The 6×6Gy hypofractionated stereotactic radiotherapy scheme seems to yield quite good results in patients with haemorrhagic brain metastases, which must be confirmed in a prospective way.


Assuntos
Neoplasias Encefálicas/radioterapia , Hemorragia Cerebral/radioterapia , Hipofracionamento da Dose de Radiação , Radiocirurgia/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias Encefálicas/mortalidade , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/secundário , Hemorragia Cerebral/etiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Radiocirurgia/efeitos adversos , Radiocirurgia/mortalidade , Estudos Retrospectivos , Fatores de Tempo , Carga Tumoral
6.
Bone Joint J ; 101-B(2): 207-212, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30700116

RESUMO

AIMS: Cementless primary total hip arthroplasty (THA) is associated with risks of bleeding and thromboembolism. Anticoagulants are effective as venous thromboprophylaxis, but with an increased risk of bleeding. Tranexamic acid (TXA) is an efficient antifibrinolytic agent, but the mode and timing of its administration remain controversial. This study aimed to determine whether two intravenous (IV) TXA regimens (a three-hour two-dose (short-TXA) and 11-hour four-dose (long-TXA)) were more effective than placebo in reducing perioperative real blood loss (RBL, between baseline and day 3 postoperatively) in patients undergoing THA who receive rivaroxaban as thromboprophylaxis. The secondary aim was to assess the non-inferiority of the reduction of blood loss of the short protocol versus the long protocol. PATIENTS AND METHODS: A multicentre, prospective, randomized, double-blind, placebo-controlled trial was undertaken involving 229 patients undergoing primary cementless THA using a posterior approach, whose extended rivaroxaban thromboprophylaxis started on the day of surgery. There were 98 male and 131 female patients, with a mean age of 65.5 years (32 to 91). The primary outcome, perioperative RBL, was evaluated at 72 hours postoperatively. The efficacy of short- and long-TXA protocols in the reduction of perioperative RBL was compared with a placebo group. RESULTS: TXA significantly reduced perioperative blood loss compared with placebo (p < 0.001); the mean differences were 525.3 ml (short-TXA vs placebo) and 550.1 ml (long-TXA vs placebo). No venous or arterial thromboembolic complications were reported. The upper boundary of the 95% confidence interval, when comparing short and long protocols, was below the pre-specified margin of non-inferiority (p = 0.027). CONCLUSION: In patients undergoing primary cementless THA, using a posterior approach, who are treated with rivaroxaban for thromboembolic prophylaxis, short- and long-TXA IV protocols are significantly more effective than placebo in reducing perioperative RBL, without any thromboembolic complications. Non-inferiority of a short- versus a long-TXA protocol in reducing perioperative RBL was supported in a secondary analysis.


Assuntos
Artroplastia de Quadril , Perda Sanguínea Cirúrgica/prevenção & controle , Fármacos Hematológicos/uso terapêutico , Artropatias/cirurgia , Rivaroxabana/uso terapêutico , Ácido Tranexâmico/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Antifibrinolíticos/uso terapêutico , Cimentos Ósseos , Cimentação , Quimioprevenção , Método Duplo-Cego , Inibidores do Fator Xa/uso terapêutico , Feminino , Articulação do Quadril/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Resultado do Tratamento
7.
Rhinology ; 55(2): 106-112, 2017 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-28501886

RESUMO

BACKGROUND: This study evaluated the efficacy of rhinophototherapy in patients with chronic rhinosinusitis (CRS) without nasal polyps. METHOD: In this randomized double-blind, placebo-controlled trial, CRS patients (n=50) received either mixed visible and ultraviolet (UVA and UVB) light source application (mUV/VIS) or visible light alone that served as placebo. Both groups were treated for 3 weeks. RESULTS: Results in the rhinophototherapy and placebo group were not significantly different and failed to reduce patient-reported outcomes measures (Rhinosinusits Disability Index, Visual Analogic Scale of symptom severity) and objective scores (rhinomanometry, olfactory thresholds, nasal Nitic Oxide concentrations), immediately and one month after treatment. CONCLUSIONS: The present data suggest that rhinophototherapy is not an efficient treatment for chronic rhinosinusitis without nasal polyps.


Assuntos
Fototerapia/métodos , Rinite/terapia , Sinusite/terapia , Administração Intranasal , Adolescente , Adulto , Idoso , Doença Crônica , Método Duplo-Cego , Endoscopia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Medidas de Resultados Relatados pelo Paciente , Estudos Prospectivos
8.
Ned Tijdschr Geneeskd ; 160: D758, 2016.
Artigo em Holandês | MEDLINE | ID: mdl-27879183

RESUMO

OBJECTIVE: The aim of this research was to assess the effect of providing personalised self-management support on patient activation (knowledge, skills, self-efficacy) and self-management behaviour. DESIGN: Cluster randomised trial in 15 general practices (Dutch Trial Register No.: NTR 3960). METHOD: Patients aged 18 years or older with a chronic condition were invited to participate in the study. The Self-Management Screening (SeMaS) questionnaire - which illustrates barriers to self-management - was used as a tool for personalised self-management support. Nurse practitioners in the intervention practices were trained for 2 hours in using SeMaS and personalising self-management support on the basis of the SeMaS profile. At baseline and after 6 months, patients filled in questionnaires on patient activation (PAM-13) and lifestyle. Using data from the questionnaires and medical records, the use of individual care plans, referrals to self-management interventions, self-monitoring and healthcare use were assessed. We used a multiple multilevel regression model for data analysis. RESULTS: After 6 months, no difference was found in patient activation between the control group (n = 348) and the intervention group (n = 296). 29.4% of the patients in the intervention group performed self-monitoring, versus 15.2% in the control group (regression coefficient r = 0.9, p = 0.01). In the per-protocol analysis (control n = 348; intervention n = 136), the number of individual care plans (r = 1.3, p = 0.04) and the number of patients performing self-monitoring (r = 1.0; p = 0.01) were higher in the intervention group. CONCLUSION: Personalised self-management support with the use of the SeMaS method stimulates self-monitoring and the use of individual care plans. The intervention had no effect on patient activation or lifestyle. Given the positive secondary outcomes, the further potential of the tool should be researched.


Assuntos
Doença Crônica/terapia , Gerenciamento Clínico , Medicina de Precisão/métodos , Autocuidado/métodos , Autoeficácia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Inquéritos e Questionários
9.
Ann Oncol ; 27(10): 1922-8, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27502701

RESUMO

BACKGROUND: Dynamic contrast-enhanced ultrasonography (DCE-US) has been used for evaluation of tumor response to antiangiogenic treatments. The objective of this study was to assess the link between DCE-US data obtained during the first week of treatment and subsequent tumor progression. PATIENTS AND METHODS: Patients treated with antiangiogenic therapies were included in a multicentric prospective study from 2007 to 2010. DCE-US examinations were available at baseline and at day 7. For each examination, a 3 min perfusion curve was recorded just after injection of a contrast agent. Each perfusion curve was modeled with seven parameters. We analyzed the correlation between criteria measured up to day 7 on freedom from progression (FFP). The impact was assessed globally, according to tumor localization and to type of treatment. RESULTS: The median follow-up was 20 months. The mean transit time (MTT) evaluated at day 7 was the only criterion significantly associated with FFP (P = 0.002). The cut-off point maximizing the difference between FFP curves was 12 s. Patients with at least a 12 s MTT had a better FFP. The results according to tumor type were significantly heterogeneous: the impact of MTT on FFP was more marked for breast cancer (P = 0.004) and for colon cancer (P = 0.025) than for other tumor types. Similarly, the differences in FFP according to MTT at day 7 were marked (P = 0.004) in patients receiving bevacizumab. CONCLUSION: The MTT evaluated with DCE-US at day 7 is significantly correlated to FFP of patients treated with bevacizumab. This criterion might be linked to vascular normalization. AFSSAPS NO: 2007-A00399-44.


Assuntos
Bevacizumab/administração & dosagem , Neoplasias/diagnóstico por imagem , Neoplasias/tratamento farmacológico , Ultrassonografia/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Inibidores da Angiogênese/administração & dosagem , Biomarcadores Tumorais , Meios de Contraste/administração & dosagem , Feminino , França , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias/patologia
10.
Sci Rep ; 6: 20899, 2016 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-26864735

RESUMO

Electron-phonon coupling is a fundamental inelastic interaction in condensed matter and in molecules. Here we probe phonon excitations using quantum interference in electron transport occurring in short chains of anthraquinone based molecular junctions. By studying the dependence of molecular junction's conductance as a function of bias voltage and temperature, we show that inelastic scattering of electrons by phonons can be detected as features in conductance resulting from quenching of quantum interference. Our results are in agreement with density functional theory calculations and are well described by a generic two-site model in the framework of non-equilibrium Green's functions formalism. The importance of the observed inelastic contribution to the current opens up new ways for exploring coherent electron transport through molecular devices.

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