Jean Marc Orgogozo

Normal cerebrovascular reactivity in Stroke-like Migraine Attacks after Radiation Therapy syndrome.

Stroke-like Migraine Attacks after Radiation Therapy (SMART) syndrome is a rare complication of cranial irradiation. Radiation is well-known to impair vascular vessel architecture and function. We investigated the hypothesis of radiation-induced cerebral vascular reserve dysfunction as the underlying mechanism of SMART. Interictal cerebrovascular reactivity was investigated using Tc-99m hexamethylpropyleneamine oxime-SPECT and acetazolamide challenge in 3 patients. We found interictal hypoperfusion and normal cerebrovascular reactivity in all patients. Neither ictal restriction of the apparent diffusion coefficient nor MR angiography abnormalities were observed. These findings do not support a vascular mechanism in SMART syndrome. Postradiation neuronal dysfunction may be the underlying mechanism. Further investigations on larger series are needed to confirm this hypothesis.

Use of the Triage Stroke Panel in a neurologic emergency service.

BACKGROUNDnAcute stroke is associated with serum elevations of numerous markers. We evaluated the additive accuracy of the Triage Stroke Panel (D-dimer, B-natriuretic peptide, matrix metalloproteinase 9, and S-100beta) to the triaging nurse for acute stroke diagnosis.nnnMETHODSnConsecutive patients with suspected stroke were included in this prospective, controlled, single-center study. A well-trained stroke center triage nurse assigned a probability that the patient had experienced a stroke (certain, very probable, probable, not likely, doubtful, or other); then, the Triage Stroke Panel testing was performed. Patients diagnosis was based on clinical and imaging data by a neurologist blinded to the test results.nnnRESULTSnTwo hundred four patients were evaluated. Confirmed strokes and transient ischemic attacks (TIAs) were observed in 131 patients. When considering an experienced stroke nurses assessment of other, doubtful, or not likely to be negative for stroke and categorizing TIA with stroke, the stroke panels Multimarker Index (MMX) value had identical accuracy (approximately 70%) and equivalent sensitivity (approximately 94%) and specificity (approximately 24%) for stroke diagnosis to that of the nurse. Combining nurse assessment with the MMX result significantly improved the specificity of diagnosing mimic vs stroke + TIA from 25.4% (nurse assessment only) to 46.0% (nurse assessment + MMX; P < .001).nnnCONCLUSIONSnThe Triage Stroke Panel provides objective information that complements a triage nurse in the assessment of a suspected stroke patient. Its performance compares favorably with that of a well-trained stroke center triage nurse, suggesting potential use in nonexpert centers for improving the accuracy of stroke diagnosis.

Magnetization Transfer Imaging Shows Tissue Abnormalities in the Reversible Penumbra

Background and Purpose— In the concept of ischemic penumbra, the volume of salvaged penumbra is considered as the volume of FLAIR normalization on follow-up MRI compared with early diffusion and perfusion abnormalities. Using magnetization transfer imaging, very sensitive to macromolecular disruption, we investigated whether FLAIR normalization was a good marker for tissue full recovery. Methods— We prospectively included 30 patients with acute middle cerebral artery stroke. Diffusion-weighted imaging (DWI) and perfusion-weighted imaging were performed within 12 hours after onset (MRI.1), and the final infarct was documented by MRI with FLAIR and magnetization transfer at 1-month follow-up (MRI.2). We compared magnetic transfer ratio of a normal region with values measured at 1 month (MRI.2) in 4 regions of interest: (1) the initial DWI hypersignal (CORE=DWI_MRI.1); (2) the infarct growth area (infarct growth=FLAIR_MRI.2−DWI_MRI.1); (3) the hypoperfused area that normalized (reversible perfusion abnormalities=perfusion-weighted imaging_MRI.1−FLAIR_ MRI.2); and (4) the early DWI abnormalities that normalized (reversible diffusion abnormalities=DWI_MRI.1− FLAIR_MRI.2). Results— In comparison with values obtained in normal tissue (magnetic transfer ratio=49.8%, SD=1.9), magnetic transfer ratio at 1 month was significantly decreased in reversible perfusion abnormalities (45.2%, SD=2.5; P<0.0001) and reversible diffusion abnormalities (43.2%, SD=2.8; P=0.0156). It was also markedly reduced, as expected, in the CORE (40.9%, SD=5.2) and infarct growth regions (43.1%, SD=2.0). Conclusions— Magnetic transfer ratio assessed presence of microstructural damages in the MRI-defined salvaged penumbra. This may imply cellular loss and partial infarction. Evaluation of the efficacy of therapies that promote reperfusion or neuroprotection may benefit from this additional information.

Accidents vasculaires cérébraux et néoplasie : évoquer la thrombose veineuse pulmonaire

Resume Les accidents vasculaires cerebraux survenant chez des patients ayant une tumeur maligne peuvent relever d’etiologies diverses. Nous rapportons un cas d’adenocarcinome bronchique avec thrombose veineuse pulmonaire s’etendant dans l’oreillette gauche revele par des infarctus cerebraux multiples.

Lymphome cérébral primitif à présentation pseudovasculaire

Resume Introduction L’expression clinique des lymphomes cerebraux primitifs peut etre polymorphe. Observation Nous rapportons le cas d’une patiente ayant presente des episodes neurologiques recidivants evocateurs d’une pathologie ischemique arterielle avec imagerie cerebrale normale. Tardivement, l’IRM mit en evidence une lesion pedonculaire dont la biopsie permit de porter le diagnostic de lymphome cerebral primitif de type B de haut grade de malignite. Conclusion Ce cas illustre la difficulte diagnostique de cette affection rare et de mauvais pronostic.

CO-27 Maladie de marchiafava-bignami : contribution de L’IRM de diffusion dans les lésions du corps calleux et du cortex

Objectifs Interet de l’IRM de diffusion dans le diagnostic et l’approche physiopathologique de la maladie de MB. Materiel et methodes Inclusion : 6 patients âges de 47 a 62 ans (4 hommes 2 femmes), tous presentent un alcoolisme chronique. Imagerie Tous les patients ont une IRM entre J1 et J5 apres le debut des troubles IRM 1,5 T protocole standardise avec des coupes axiales de 7 mm, T1 (TR580/TE15ms) sans et avec gadolinium, T2 Flair (TR10000/TE110/Ti2380ms), Diffusion (TR6000/TE114ms) avec 2 valeurs de b( b = 0 ; b = 1 000 s/mm2) le gradient est experimente selon 3 axes (xyz) avec generation de carte de Coefficient Diffusion Apparent. Resultats 3 patients sur 6 presentent une atteinte corticale, ces 3 patients ont une evolution pejorative (2 deces, 1 syndrome dementiel severe). Dans tous les cas il existe un hypersignal T2 du corps calleux et une restriction du Coefficient de Diffusion Apparent. Aucun signe IRM pour une autre complication alcoolisme chronique (Gayet Wernicke, myelinolyse centro ou extra pontine). Conclusion La maladie de MB n’est pas exclusivement une pathologie du corps calleux. L’atteinte corticale n’est pas rare et doit etre recherchee, elle pourrait un element pronostic. La physiopathologie n’est pas univoque et sera discutee en fonction des resultats et des donnees de la litterature en particulier de spectroIRM et neuropathologiques.