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J-L Mas

Publications and source records attributed to J-L Mas.

10 recordsLinked to original sources

Do transient ischemic attacks with diffusion-weighted imaging abnormalities correspond to brain infarctions?

BACKGROUND AND PURPOSE: Our aim was to determine whether diffusion-weighted imaging (DWI) changes associated with transient ischemic attack (TIA) are reversible or correspond to permanent tissue injury. METHODS: Among 103 consecutive patients admitted for TIA, 36 (34.9%) had abnormalities on initial DWI (delay from TIA = 30 +/- 33 hours [mean +/- SD]). Thirty-three patients (59 DWI lesions) had an MR imaging follow-up (delay from TIA = 10.6 +/- 5 months) including fluid-attenuated inversion recovery, T2, DWI, and 3D T1-weighted sequences. For each lesion, we recorded the quantitative parameters on initial DWI (volume, apparent diffusion coefficient [ADC]) and performed a comparison between reversible and irreversible lesions. RESULTS: MR imaging failed to detect any permanent injury in 7 patients and identified subsequent infarct in regions corresponding to the original DWI abnormalities in 26 patients (79%). Of the 59 lesions initially identified on DWI, 45 (76.3%) were associated with permanent injury on follow-up MR imaging. The DWI volume was significantly larger (0.91 +/- 1.7 versus 0.21 +/- 0.21 cm(3), P = .003) and the ADC ratio values lower (79 +/- 15% versus 91 +/- 9%, P = .001) in lesions with subsequent infarct than in those that were fully reversible. CONCLUSION: By showing that most patients with DWI-positive TIAs share the same imaging outcome as stroke patients, our data provide additional support for the redefinition of TIA, which considers that all cases of transient deficit with characteristic neuroimaging abnormalities should be diagnosed as a stroke.

Adult↗

[Spontaneous thrombosis of lesion-free carotid arteries: a retrospective analysis of eight patients].

Strokes are rarely secondary to spontaneous carotid artery thrombosis. The objectives of this retrospective analysis were to define characteristic features and the clinical course. The study population included eight patients (6 females/2 males) seen at six university neurological centers. Age of onset was 46.5 years (range 38-52). Half of the patients had no vascular risk factor. Symptoms were TIA (n=1), strokes (n=7). Echotomography revealed intraluminal thrombus, with occlusion in 2 cases. Thrombi were found in common carotid artery (n=3), carotid bifurcation (n=2) and internal carotid artery (n=3). The thrombus was mobile in 4 cases. Seven patients were treated by anticoagulation therapy, one by surgery because of recurrent TIA. Further echotomographic exams revealed total resolution (3 cases) or decrease of the thrombus (3 cases). Occlusion was definitive in one patient. A cause was identified in six patients: acute leukemia (n=1), thrombocytopenic purpura (n=1), iron deficiency anemia (n=4).

Adult↗

[MRI of acute ischemic stroke].

The advent of new MR techniques such as perfusion and diffusion weighted imaging has revolutionized diagnostic imaging in stroke. In some institutions, MRI is used as the sole screening imaging technique for acute stroke patients. In this document, the authors will review the MR pattern of acute ischemic arterial stroke, highlight the usefulness of MRI for the identification of acute hematomas and stroke like episodes, present the potential use of MRI in the management of acute stroke patients, especially when thrombolysis is contemplated, and discuss the role of MRI for imaging transient ischemic attack.

Cerebral Hemorrhage↗

Atherothrombosis: management of patients at risk.

Vascular disease is the most common cause of mortality and morbidity on a worldwide basis and represents a major social burden. Atherothrombosis, which is one of the disease processes underlying vascular disease, consists of thrombus formation superimposed upon an existing atherosclerotic lesion. A number of factors are associated with the risk of developing atherothrombotic clinical events, such as myocardial infarction (MI) or ischaemic stroke (IS). The most significant of these include a previous vascular event (such as MI or IS), hypertension, obesity, diabetes and smoking. Encouraging patients to institute lifestyle modifications such as weight loss and smoking cessation can significantly reduce the risk of experiencing a primary or secondary vascular event. Lifestyle modifications must be supplemented with pharmacological therapies if a significant risk reduction is to be achieved. Studies have shown that antihypertensives, statins and antithrombotic agents are the most successful agents in reducing vascular risk and avoiding unpredictable and life-threatening atherothrombotic events.

Antihypertensive Agents↗

Risk of stroke and recurrent dissection after a cervical artery dissection: a multicenter study.

OBJECTIVE: To assess the risk of stroke, TIA, or dissection recurrence after a first event of cervical artery dissection (CAD). METHODS: The authors undertook a historical cohort study of consecutive patients with a first event of CAD who were admitted in 24 departments of neurology within a period of at least 1 year. Patients were retrospectively selected from a stroke data bank or from the local administrative data bank using the 10th revision of the International Statistical Classification of Diseases. A neurologist and a radiologist reviewed all charts to validate diagnosis and collect data. In 2002, patients were interviewed by phone or during a visit by the local investigators. RESULTS: Four hundred fifty-nine patients (mean age 44.0 +/- 9.7 years) were included in the study. Among the 457 survivors, 25 (5.5%) could not be contacted in 2002 because they had moved. After a mean follow-up of 31 months, four (0.9%) patients presented a recurrent ischemic stroke attributable to either not yet completely recovered initial CAD (n = 2) or a recurrent CAD (n = 2). Eight (1.8%) patients had a TIA without CAD recurrence. Two TIA occurred at the acute stage of CAD. Of the six remaining TIA, only one was associated with chronic arterial stenosis. In addition, two patients had recurrent CAD without stroke, giving a total of four (0.9%) CAD recurrences. CONCLUSIONS: Patients with a first event of CAD have a very low risk of ischemic events or dissection recurrences. Ischemic events seem rarely to be in relation with chronic arterial lesions.

Adult↗

[Diffusion tensor MRI of Wallerian degeneration: a case report].

Diffusion tensor imaging allows a 3D analysis of water molecular motion and an exploration of white matter tracts integrity and orientation. We report a diffusion tensor study of wallerian degeneration of the corticospinal tract following a capsulo-lenticular hemorrhage in a 49-year old man. Reduced anisotropy (loss of fiber coherence) with preserved diffusivity of the damaged corticospinal tract was observed. This highlights the feasibility of diffusion tensor imaging on clinical MR units and its ability to quantify the degree of white matter tract destruction.

Anisotropy↗