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J L Mas

Publications and source records attributed to J L Mas.

At least 19 recordsLinked to original sources
PubMed2006

Lack of validity of a French adaptation of a scale measuring attitudes towards clinical practice guidelines.

BACKGROUND: Valid instruments to measure practitioners' attitudes towards clinical practice guidelines need to be developed. However, few of the available instruments have been thoroughly validated. OBJECTIVE: To adapt into French and to test the reliability and validity of a scale for measurement of attitudes towards guidelines developed by Elovainio et al. METHODS: A 27-item scale (divided into six dimensions) measuring attitudes towards guidelines was translated into French by two English native translators, reviewed and finalized by expert committee and administered to 314 practitioners who agreed to participate. Main practitioners' characteristics were collected. Item and dimension reproducibility were assessed for 62 practitioners by calculation of intraclass correlation coefficients. Internal construct validity was assessed by principal components analyses. Convergent and discriminant validity were analysed. RESULTS: Item response rates ranged from 82 to 100%. In the test-retest procedure, intraclass correlation coefficients for separate items ranged from 0.1 to 0.7 and those for dimensions were 0.7 [95% confidence interval (CI): 0.5-0.8] for usefulness, 0.5 (0.3-0.6) for reliability, 0.4 (0.2-0.5) for individual competence, 0.5 (0.3-0.6) for organizational competence, 0.7 (0.5-0.8) for impracticality and 0.4 (0.3-0.6) for availability. The factorial structure after Varimax rotation showed that none of the different solutions obtained had a strictly comparable structure to that of the original scale. External construct validity was satisfactory. CONCLUSION: This scale does not have satisfactory psychometric properties and therefore cannot confidently be used in future research assessing whether attitudes towards guidelines are a determining factor in physicians' compliance with guidelines. More research is needed to develop valid scales in a more rigorous procedure, involving qualitative and quantitative steps.

Attitude of Health Personnel↗
PubMed2006

Diffusion-weighted MR imaging in transient ischaemic attacks.

The purpose of this study was to determine frequency and the characteristics of diffusion-weighted imaging (DWI) abnormalities in patients with transient ischaemic attack (TIA). We analysed data of 98 consecutive patients (mean age: 60.6+/-15.4 years, 56 men) admitted between January 2003 and April 2004 for TIA. Age, gender, symptom type and duration, delay from onset to magnetic resonance imaging (MRI), probable or possible TIA and cause of TIA were compared in patients with (DWI+) and without (DWI-) lesions on DWI. Volume and apparent diffusion coefficient (ADC) values of DWI lesions were computed. DWI revealed ischaemic lesions in 34 patients (34.7%). Lesions were small (mean volume: 1.9 cm(3)+/-3.3), and ADC was moderately decreased (mean ADC ratio: 79.5%). The diagnosis of TIA was considered as probable in all DWI+ patients. A multiple logistic regression model demonstrated that TIA duration greater than or equal to 60 min (OR, 7.6; 95% CI, 2.3-25.7), aphasia (OR, 9.2; 95% CI, 2.7-31.4) and motor deficit (OR, 5.1; 95% CI, 1.5-17.8) were independent predictors of DWI lesions. Prolonged TIA duration, aphasia and motor deficits are associated with DWI lesions. More than half of TIA patients with symptoms lasting more than 60 min have DWI lesions.

Adult↗
PubMed2006

[Cerebral arterial infarction and diffusion tensor imaging].

PURPOSE: Diffusion-weighted imaging (3 directions) and diffusion tensor imaging (9 directions) were compared for their sensitivity to detect ischemic lesion. MATERIALS AND METHODS: 41 patients (18 supposed transient ischemic attacks, 23 arterial stroke, MRI<or=48h) presenting with stroke syndrome were imaged using two diffusion sequences (3 directions, 2 excitations, acquisition time: 40 seconds and 9 directions, 1 excitation, acquisition time: 50 seconds, other parameters being identical). The following variables were compared (Wilcoxon test): number and extent of lesions, MRI signal and absolute ADC values, relative signal intensity and ADC ratio. Fractional anisotropy was measured within the principal lesion on the 9 directions sequence. RESULTS: 24 patients presented a lesion on both sequences. Four of them (including one TIA) had more lesions (<5 mm) on the 9 directions sequence than on the 3 directions sequence. Both sequences were normal for the 17 remaining patients (TIA=4, differential diagnosis=7, indeterminate=6). No significant difference was found for the other study parameters between 3 vs 9 directions sequences. There was a 10% decrease of the mean fractional anisotropy in ischemic lesion. CONCLUSION: By showing more lesions than standard diffusion-weighted imaging and providing quantitative anisotropy measurements, diffusion tensor imaging could replace the standard 3 directions diffusion-weighted sequence.

Adult↗
PubMed2006

[Clinical evolution of patients following investigation of atrial vulnerability after a first cerebral ischaemic accident].

Atrial vulnerability reflects the ability of the atrium to fibrillate. ISAV (Ischemic stroke and atrial vulnerability) is a French epidemiological registry whose main goal is to assess the evolution modalities of patients in whom an electrophysiological study of the atrium has been performed. A group of 269 patients with a history of non elucidated ischemic stroke and an electrophysiological study of the atrium performed in a mean delay of 3 months after the stroke has been included. Their mean age at the time of the stroke was 55 +/- 15.8 years. The electrophysiological study has measured the effective refractory period of the atrium, the locoregional right intra-atrial conduction time, the index of latent atrial vulnerability and assessed the inductibility. The mean delay between the date of the stroke and the date of the last news was 4.4 +/- 2.8 years. We observed 12 deaths and 11 patients presented during the follow up a spontaneous atrial arrhythmia and 17 a recurrence of stroke. If we consider the occurrence of the 28 combined events (atrial arrhythmia and/or stroke), it is not correlated with the presence of an atrial septal defect nor with the existence of an atrial vulnerability. On the contrary this occurrence is correlated with tobacco consumption and/or arterial hypertension; 82% of patients have these risk factors versus 54% of patients without events (p = 0.004). This association is not significant in patients younger than 55 years.

Adult↗
PubMed2005

An assay on the effect of preliminary restoration tasks applied to a large TENORM wastes disposal in the south-west of Spain.

A large industrial wastes disposal site, where two phosphate rock processing plants release their wastes, located close to Huelva town (SW of Spain), has been partially submitted to restoration as a preliminary step in a possible decomissioning process. Due to the high natural radioactivity contents of these wastes, this repository is considered as a radiological anomaly, being actually considered as TENORM (technically enhanced naturally occurring radioactive materials). The efficiency of this restoration from the radiological point of view according to the new European regulatory framework was evaluated in this work. The results allow to conclude that, as a consequence of the partial restoration works, the external dose rate has been drastically reduced above the repository system. Nevertheless, special attention must be paid on the occupational factor to be applied to workers on the unrestored system. The application of a dosimetric model allows the prediction of the negative effects of using certain industrial wastes as a cover system in this restoration/mitigation task.

Calcium Sulfate↗
PubMed2005

[Diagnosis and follow-up of cervical arterial dissections--results of the SFNV-SFNR study].

INTRODUCTION: the objective of this study was to determine the role of radiological techniques in the diagnosis, assessment of severity and follow-up of cervical arterial dissections. MATERIAL AND METHODS: from 1995 to 2001 a multicentre retrospective study was conducted in 24 hospital centers. A multiple-choice questionnaire was sent to each center in order to collect clinical information and imaging details regarding the diagnosis and follow-up of cervical arterial dissections. RESULTS: information was gathered on 459 patients, comprising a total of 384 carotid artery dissections and 170 vertebral artery dissections. A mean of 4.85 diagnostic examinations per patient were conducted. Morphological imaging of the brain by CT or by MRI was performed on all except 3 patients. Cervical Doppler ultrasound examination was the most frequently performed test throughout the entire study period (performed in 87% of patients). Conventional arteriography was a routinely employed test in 1995 whereas by 2001 it comprised only 31.2% of requested examinations, having been progressively replaced by MRI and MRA scanning, which comprised 60% of all examinations performed by 2001. A combination of cervical Doppler ultrasonography, axial MRI and MRA of the neck vessels were performed in 39.6% of patients in 2001. Examination of the intracranial vessels was performed by transcranial Doppler ultrasound in 40% of cases and by MRA in 30% of cases. For the follow-up of arterial dissections, an average of 1.4 examinations was performed per patient. The majority of such follow-up examinations comprised Doppler ultrasound and/or MRA of the neck arteries. CONCLUSION: The imaging diagnosis and follow-up of cervical arterial dissections will increasingly rely on non-invasive imaging techniques.

Carotid Artery, Internal, Dissection↗
PubMed2005

[Screening strategies for the diagnosis of asymptomatic arterial lesions in patients with atherothrombosis].

Atherosclerosis is a ubiquitous inflammatory disease. Patients presenting an acute atherothrombotic event (acute coronary syndrom, stroke, aortic aneurysm, ...) have an increased risk of events in remote arterial territories affected by atherosclerosis. These patients could benefit from systematic screening of asymptomatic atherosclerotic lesions to avoid these complications. For each atherosclerotic territory (coronary artery, carotid artery, aorta, peripheral arteries including renal arteries), we review the methods for screening asymptomatic atherothrombotic lesions which could justify specific treatments: coronary artery stenosis > or = 50%, carotid artery stenosis > or = 60%, renal artery stenosis > or = 50%, and abdominal aortic aneurysm > or = 30 mm. This review shows that non invasive methods (ie, echography, tomodensitometry) are widely available for diagnosis of asymptomatic lesions in carotid and renal arteries, and in the aorta. Despite its invasive caracteristic, coronarory angiography remains the gold-standard for the diagnosis of coronary artery disease. However, cardiac multi-slices CT-scan appears a promising technique for asymptomatic patients.

Arterial Occlusive Diseases↗
PubMed2005

[Prevalence of asymptomatic atherothrombotic lesions and risk of vascular events in patients with a stroke].

OBJECTIVE: To estimate the prevalence of asymptomatic atherothrombotic lesions and the absolute risk of vascular events in patients with ischemic stroke. METHODS: We conducted a systematic review of studies published between 1980 and 2004 which allowed calculating prevalence of asymptomatic lesions and absolute risks of vascular events in stroke patients. Studies included in the review of absolute risks had to include at least 100 patients followed for at least 1 year and with less than 5% of lost to follow-up. RESULTS: Coronarography was used in only one study which does not provide any precise estimation of the prevalence of asymptomatic coronary lesions. Depending on the population and the method used for the diagnosis of coronary disease, the prevalence of asymptomatic coronary artery disease ranged from 25 through 60%. Very few studies have been devoted to the prevalence of abdominal aortic disease in stroke patients. The prevalence of abdominal aortic aneurysm has been estimated to 1% and that of peripheral arterial disease to 10%. Thirty-six cohorts were identified. The absolute risk of myocardial infarction was about 2%/year and that of vascular death 2%/year. CONCLUSION: Stroke patients carry a high risk of coronary and vascular events. Additional studies are required to better identify patients with a high prevalence of asymptomatic atherosclerotic lesions and with a high risk of vascular events.

Atherosclerosis↗
PubMed2005

[Risk factors management in 5708 ambulatory patients suffering from peripheral vascular disease followed in urban practices].

STUDY OBJECTIVE: we examined the management of risk factors in patients suffering from obliterating peripheral arterial disease (OPAD), in urban medical practice. METHODS: PRISMA, ECLAT1 and APRES are surveys based on urban medicine in France. These 3 studies have allowed a compilation of data pertaining to the control of risk factors in patients suffering from one or more clinical manifestations of atherothrombosis, including cerebral vascular accident, coronary insufficiency or OPAD. The study population was divided among patients with isolated OPAD, versus OPAD associated with coronary artery disease (CAD), versus OPAD associated with cerebral vascular disease. RESULTS: a total of 5 708 patients with stable OPAD were included among the 3 studies. Risk factors were not managed in the majority of patients, including 62.6% of hypercholesterolemic patients, 71.1% of diabetics, and 77.4% of hypertensive patients. Overall, the control of risk factors was less satisfactory in patients with OPAD than in patients with CAD. Smoking (70.6% current or past smokers) remains a major risk factor in OPAD. The proportion of current smokers was significantly higher is the group with isolated OPAD than in the other 2 groups of patients (p < 0.0001). CONCLUSIONS: The control of risk factors in patients with OPAD is suboptimal, mainly because of failure to reach the therapeutic goals, rather than because of poor medical management. It is important that recent recommendations be implemented in medical practice. Awareness of the primary physicians will be key in the optimisation of treatment prescriptions and, above all, in the achievement of a higher level of clinical performance.

Adult↗
PubMed2004

Spectroscopy and serial diffusion MR findings in hGH-Creutzfeldt-Jakob disease.

This report describes the magnetic resonance imaging (MRI) findings in two patients fulfilling the diagnostic criteria for human growth hormone Creutzfeldt-Jakob disease, who initially had pronounced bilateral DWI/FLAIR (diffusion weighted imaging/fluid attenuated inversion recovery) hyperintensities in the basal ganglia, with decreased apparent diffusion coefficient (ADC) values (range, 58-82% of normal). MRI spectroscopy, obtained in one case, showed decreased N-acetyl aspartate/creatine (NAA/Cr) ratio in the atrophic vermis (0.79; normal: mean, 1.20; SD, 0.13), despite the lack of DWI/FLAIR signal changes, whereas NAA/Cr was normal in the putamina (1.6; normal: mean, 1.56; SD, 0.17), despite striking DWI signal changes and decreased ADC values (60% of normal). Serial DWI, obtained in the other case, showed a progressive disappearance of DWI hypersignal of the basal ganglia replaced by pronounced atrophy. Data from these two patients suggest that restricted diffusion associated with a normal NAA value might indicate spongiform changes of still viable cells, and that any subsequent regression of the DWI signal changes, atrophy, or decreased NAA values could be related to progressive neuronal death.

Adult↗
PubMed2004

Spinal cord infarction: clinical and magnetic resonance imaging findings and short term outcome.

BACKGROUND: Most studies on spinal cord infarction have been conducted in single centres; they usually consisted of case reports, or of larger series of patients recruited over a large period of time, with heterogeneous diagnostic procedures. Therefore, the clinical and radiological presentation of spinal cord infarcts and their short term outcome remain poorly understood. OBJECTIVE: To define clinical and magnetic resonance imaging (MRI) findings, and short term outcome in patients with spinal cord infarcts. METHODS: The authors prospectively included patients within 10 days of onset. An MRI scan was required and repeated when initially normal. RESULTS: Twenty eight consecutive patients were included over a 24 month period in 16 neurological centres. The infarct was cervical in seven patients, thoracic in three, thoracolumbar in 15, and restricted to the conus in three. On axial MRI scans the infarct was located in the central territory of the anterior spinal artery in 21 patients, and in the peripheral arterial territory in three. At month two, 15 patients had a good outcome and 13 had a poor outcome, including three deaths. Patients who, at onset, could not walk, had bladder dysfunction, or proprioceptive deficits were more likely to have a poor outcome. At month two, pain had occurred in 10 of the 25 survivors and was associated neither with the initial severity, nor the extent of the infarct on MRI. CONCLUSION: The two month outcome mainly depends on the initial severity of the neurological deficit; however, a few patients with a severe impairment at onset had a good outcome, especially when proprioception remained normal at onset. The study does not support the hypothesis that pain occurs more frequently in small spinal infarcts.

Adult↗
PubMed2004

Neuroimaging in posterior reversible encephalopathy syndrome.

The terms posterior reversible leukoencephalopathy, reversible posterior cerebral edema syndrome, and posterior reversible encephalopathy syndrome (PRES) all refer to a clinicoradiologic entity characterized by headaches, confusion, visual disturbances, seizures, and posterior transient changes on neuroimaging. Clinical findings are not sufficiently specific to readily establish the diagnosis; in contrast, magnetic resonance imaging pattern is often characteristic and represents an essential component of the diagnosis of PRES. Typical lesions predominate in the posterior white matter, with some involvement of the overlying cortex; are hyperintense on T2-weighted images; and are usually hypointense or isointense on diffusion-weighted images, with an increase of the apparent diffusion coefficient, indicating vasogenic edema. The pathogenesis is incompletely understood, although it seems to be related to the breakthrough of autoregulation and endothelial dysfunction. Since its initial description, this syndrome has been subsequently described in an increasing number of medical conditions, including hypertensive encephalopathy, eclampsia, and the use of cytotoxic and immunosuppressive drugs. The diagnosis has important therapeutic and prognostic implications because the reversibility of the clinical and radiologic abnormalities is contingent on the prompt control of blood pressure and/or discontinuing the offending drug. On the contrary, when unrecognized, conversion to irreversible cytotoxic edema may occur.

Brain↗
PubMed2003

Carotid angioplasty and stenting with and without cerebral protection: clinical alert from the Endarterectomy Versus Angioplasty in Patients With Symptomatic Severe Carotid Stenosis (EVA-3S) trial.

BACKGROUND AND PURPOSE: Whether cerebral protection during carotid angioplasty and stenting (CAS) is associated with a lower risk of periprocedural stroke or death remains to be established. We report on 80 patients randomized in the CAS arm of the Endarterectomy Versus Angioplasty in Patients With Symptomatic Severe Carotid Stenosis trial comparing CAS (with or without cerebral protection) with carotid surgery in patients with recently symptomatic, severe carotid stenosis. SUMMARY OF REPORT: The Safety Committee recommended stopping unprotected CAS, because the 30-day rate of stroke was 3.9 (0.9 to 16.7) times higher than that of CAS with cerebral protection (4/15 versus 5/58). CONCLUSIONS: Although this result was not based on a randomized comparison of unprotected versus protected CAS, it suggests that the use of cerebral protection devices during CAS reduces periprocedural strokes.

Angioplasty↗
PubMed2003

Early asymptomatic recurrence of cervical artery dissection: three cases.

Cervical artery dissection (CAD) recurrences are rare but the risk could be higher during the first month. Twenty-seven consecutive patients admitted for an acute CAD were investigated using a standardized imaging protocol. An early asymptomatic recurrence was observed in three patients 49 to 53 days after the initial diagnosis. Anticoagulation was maintained and the prognosis remained good. Early CAD recurrences may have been underestimated previously, because asymptomatic recurrences seem to be more frequent than symptomatic ones.

Adult↗
PubMed2003

Early and late seizures after cryptogenic ischemic stroke in young adults.

OBJECTIVES: To assess the incidence and predictive factors of early and late seizures after ischemic stroke in young adults. METHODS: A total of 581 patients (aged 18 to 55 years) with recent cryptogenic ischemic stroke were prospectively enrolled at 30 neurology departments and followed for 37.8 +/- 9.7 months. Early seizures (occurring within 7 days of stroke) were assessed by chart review and late seizures were prospectively recorded at each follow-up visit. Clinical and brain imaging findings were reviewed by two neurologists and two neuroradiologists who were blinded to the occurrence of seizures. RESULTS: Fourteen of the 581 patients (2.4%) developed early seizures, 71% of which occurred within the first 24 hours. Rankin scale >or=3 (odds ratio [OR] 3.9, 95% CI 1.2 to 12.7) and cortical involvement (OR 7.7, 95% CI 1.0 to 61.1) were independently associated with early seizures. Late seizures occurred only in patients with hemispheric stroke (n = 20). The risk of first late seizure was 3.1% (95% CI 1.4 to 4.8) within 1 year and 5.5% (95% CI 3.1 to 7.9) within 3 years. The mean delay between stroke and first late seizure was 12.9 months (0.3 to 33.9). Late seizures were associated with early seizure (hazard ratio [HR] 5.1, 95% CI 1.8 to 14.8), cortical signs (HR 4.5, 95% CI 1.6 to 13.1), and size of infarct superior to one-half hemisphere (HR 9.7, 95% CI 3.1 to 30.8). Eleven of the 20 patients with late seizure experienced recurrences (multiple in eight) on antiepileptic drug treatment. Most of them were seizure free at the end of the follow-up. CONCLUSION: Epilepsy is rarely a major problem in young cryptogenic ischemic stroke survivors. Early seizures are associated with stroke disability and cortical involvement. Early seizures, cortical signs, and large infarct are independent risk factors for late seizures.

Adult↗
PubMed2003

[Prevalence and management of patients with a prior history of atherothrombotic disease in primary care in France. Results of the ECLAT1 survey].

This cross-sectional study assessed the prevalence of subjects with a previous history of atherothrombotic disease (myocardial infarction, ischemic stroke and/or lower limb arterial disease) among patients treated in general medicine. A random sample of 3,009 French general practitioners was recruited. Patients who consulted one of these general practitioners on December 7th 2000 were included. Those with a previous history of atherothrombotic disease were identified and further data on their cardiovascular risk factors and drug use were collected. The prevalence of patients with a previous history of atherothrombotic disease was 2% [95% confidence interval: 1.9-2-1] in subjects younger than 65, 13.4% [12.7-14.2] between 65 and 74 and 17.0% [16.2-17.8] in subjects older than 74. Arterial hypertension was found in 62.2% of the patients with a previous history of atherothrombotic disease, overweight or obesity in 59.4%, hypercholesterolaemia in 55%, current or past smoking in 48.3%, and diabetes mellitus in 20.1%. The last blood pressure and LDL-cholesterol measurements were respectively higher than or equal to 140/90 mmHg and 3 mmol/l in 70.6% of the patients suffering from arterial hypertension (missing data in 2.2%) and in 48.2% of the patients suffering from hypercholesterolaemia (missing data in 31.4%). Atherothrombosis represents a significant part of the primary care activity in France. Despite a widespread antihypertensive and hypocholesterolaemic drug prescription, the control of cardiovascular risk factors is insufficient. The high prevalence of overweight may contribute to this poor control.

Adult↗