Optimized acute stroke pathway using medical advanced regulation for stroke and repeated public awareness campaigns.

OBJECTIVE: The aim of this study is to evaluate the efficiency of a specific organizational model for early stroke management associated with repeated public awareness campaigns on stroke warning signs. METHOD: Our model is based on initial telephone triage of potential candidates for an intravenous thrombolysis by an emergency physician before a 3-party conference including basic life support team on scene and a stroke neurologist. We performed a time series analysis for a period of 5 years and a half, comparing the number of emergency telephone calls with that of intravenous thrombolysis treatment realized. RESULTS: In our organizational model, repeated awareness public campaigns increased both the number of emergency calls for suspected stroke and the selection of potential candidates for intravenous thrombolysis. Results from the time series analysis suggest that educational campaigns are a major factor influencing our emergency medical service activity. This result is correlated with the number of performed intravenous thrombolyses by the stroke center especially within a 3-hour delay (Spearman ρ, P = .621, P = .000 and P = .439, P = .000, respectively). CONCLUSION: Educational programs repeated each year are useful to the population for learning how to recognize stroke symptoms and send straight away an emergency call. Combining the emergency action with an early remote evaluation by the stroke center team and a direct admission in imaging department shortens the time-to-treatment delay. This model is reproducible in different health care systems.

Acute cerebral vasculopathy in systemic sclerosis.

Systemic sclerosis is an autoimmune disease characterized by skin and deep organ fibrosis and obliterative microvasculopathy. Cerebral involvement is currently not recognized as a manifestation of the disease, although several morphologic and functional studies suggested a frequent cerebral involvement in systemic sclerosis. We report a new case of acute cerebral vasculopathy in a patient suffering from systemic sclerosis together with five historical cases identified through a literature review. Cerebral acute vasculopathy most often revealed the disease. Affected patients suffered often from limited or diffuse cutaneous systemic sclerosis. Reversibility of arterial lesions, absence of specific histologic findings, and association with severe peripheral vascular involvement plead for a major role of vasospasm. However, the apparent efficacy of immunosuppressive treatments suggests an association with inflammatory or immune mechanisms. Awareness should be raised because of the severity of the disease, the risk of relapse, and the possible occurrence early in the course of systemic sclerosis.

Progressive dementia associated with ataxia or obesity in patients with Tropheryma whipplei encephalitis.

BACKGROUND: Tropheryma whipplei, the agent of Whipple's disease, causes localised infections in the absence of histological digestive involvement. Our objective is to describe T. whipplei encephalitis. METHODS: We first diagnosed a patient presenting dementia and obesity whose brain biopsy and cerebrospinal fluid specimens contained T. whipplei DNA and who responded dramatically to antibiotic treatment. We subsequently tested cerebrospinal fluid specimens and brain biopsies sent to our laboratory using T. whipplei PCR assays. PAS-staining and T. whipplei immunohistochemistry were also performed on brain biopsies. Analysis was conducted for 824 cerebrospinal fluid specimens and 16 brain biopsies. RESULTS: We diagnosed seven patients with T. whipplei encephalitis who demonstrated no digestive involvement. Detailed clinical histories were available for 5 of them. Regular PCR that targeted a monocopy sequence, PAS-staining and immunohistochemistry were negative; however, several highly sensitive and specific PCR assays targeting a repeated sequence were positive. Cognitive impairments and ataxia were the most common neurologic manifestations. Weight gain was paradoxically observed for 2 patients. The patients' responses to the antibiotic treatment were dramatic and included weight loss in the obese patients. CONCLUSIONS: We describe a new clinical condition in patients with dementia and obesity or ataxia linked to T. whipplei that may be cured with antibiotics.

Stroke in a young patient treated by alteplase heralding an acquired thrombotic thrombocytopenic purpura.

BACKGROUND AND PURPOSE: Thrombotic thrombocytopenic purpura (TTP) is a life-threatening multisystem disorder characterized by thrombocytopenia and fluctuating neurological symptoms due to microinfarcts. In rare cases, large cerebral arteries can be occluded. SUMMARY OF THE CASE: We report on a 30-year-old woman with a first-ever acute stroke related to a right proximal MCA M1 occlusion. Platelet count was normal at admission and progressively decreased 6 days after intravenous thrombolysis with the occurrence of a hemolytic anemia with schistocytes. Most biological anomalies reversed after plasma exchange. No hemorrhagic complication occurred. Diagnosis of initial TTP was confirmed by low ADAMTS13 activity and positivity of anti-ADAMTS13 antibody. CONCLUSION: This observation highlights the fact that even if platelet count and hemoglobin rate are normal in the beginning, an acute ischemic stroke in a young patient can be related to TTP. Faced with subsequent thrombopenia, practitioners should be aware of acquired TTP, and, thus, schistocytes, haptoglobin, and LDH assays should be performed. Early diagnosis is paramount to start the life-saving plasma exchanges.

Grid-free interactive and automated data processing for MR chemical shift imaging data.

PURPOSE: Today's available chemical shift imaging (CSI) analysis tools are based on Fourier transform of the entire data set prior to interactive display. This strategy is associated with limitations particularly when arbitrary voxel positions within a 3D spatial volume are needed by the user. In this work, we propose and demonstrate a processing-resource-efficient alternative strategy for both interactive and automated CSI data processing up to three spatial dimensions. METHODS: This approach uses real-time voxel-shift by first-order phase manipulation as a basis and therefore allows grid-free voxel positioning within the 3D volume. The corresponding spectrum is extracted from the 4D data (3D spatial/1D spectral) at each time a voxel position is selected. The spatial response function and hence the exact voxel size and shape are calculated in parallel including the same processing parameters. Using this mechanism sequentially along with AMARES time-domain modeling, we also implemented automated quantitative and B (0)-insensitive metabolite mapping. RESULTS: Metabolite maps of N-acetyl aspartate, choline and creatine were generated using (1)H-CSI data from the brain of healthy volunteers and patients with tumor and epilepsy. (31)P-3D-CSI of the heart of a healthy volunteer is also shown. CONCLUSION: The calculated metabolite maps demonstrate good stability and accuracy of the algorithm in all situations tested. The suggested algorithm constitutes therefore an attractive alternative to existing CSI processing strategies.

Use of proton magnetic resonance spectroscopy of the brain to differentiate gliomatosis cerebri from low-grade glioma.

OBJECT: Gliomatosis cerebri (GC), a rare entity characterized by a widespread infiltration of brain by tumor, lacks objective and quantitative diagnostic criteria. Single-voxel spectroscopy and chemical shift imaging (two-dimensional proton magnetic resonance [MR] spectroscopy) were performed using both short (20- or 22-msec) and long (135-msec) echo times in nine patients suffering from GC, nine patients with low-grade gliomas (LGGs), and 25 healthy volunteers to establish the precise metabolic pattern of this uncommon brain neoplasm. METHODS: The gliomatosis infiltration was characterized by markedly elevated levels of creatine-phosphocreatine (Cr) and mvo-inositol (Ins), a reduced level of N-acetyl aspartate (NAA), and a moderately elevated level of choline-containing compounds (Cho). This pattern differs strikingly from LGGs, which are characterized by elevated levels of Cho and Ins, markedly reduced levels of NAA, and low-to-normal Cr concentrations. Although the distinction between GC and LGG, based on histological and MR imaging criteria, is a matter of debate, MR spectroscopy produces valuable information for the differentiation between these two entities and, hence, the choice of therapeutic strategy. It also provides new insight into the pathophysiology of GC because elevated Cr and Ins levels may be related to proliferation of glial elements or, more probably, activation of normal glia. Elevated levels of Cho reflect cellular proliferation and reduced NAA corresponds to reversible neuronal injury and/or focal invasion by the tumor process. CONCLUSIONS: Owing to the unfavorable clinical outcome associated with GC compared with that associated with LGG, the findings of this study illustrate the diagnostic and prognostic value of proton MR spectroscopy in the characterization of infiltrating gliomas.

The role of sonolysis and sonothrombolysis in acute ischemic stroke: a systematic review and meta-analysis of randomized controlled trials and case-control studies.

OBJECTIVES: To assess the evidence on the safety and efficacy of sonothrombolysis in acute stroke. SEARCH METHODS: Electronic databases and grey literature were searched under different MeSH terms from 1970 to present. SELECTION CRITERIA: Randomized control trials (RCTs) and case control studies (CCSs) on sonolysis and sonothrombolysis alone or with microsphere in acute stroke patients (>18 old). Outcome measures included complete recanalization (CR) at 1-2 and 24 hours, 3 months modified Rankin Scale (mRS), and symptomatic intracerebral hemorrhage (sICH). Data was extracted to Review Manager software. RESULTS: Fifty-seven studies were retrieved and analyzed. Ten studies (7 RCTs and 3 CCSs) were included in our meta-analysis, which revealed that sonolysis and sonothrombolysis are safe (OR of sICH: 1.14; 95% confidence interval (CI): 0.56- 2.34;P=0.71) and effective (OR of CR at 1-2 hours: 2.95;95% CI: 1.81-4.81;P<0.00001) and have more than two-fold higher likelihood of favourable long-term outcome (3-month mRS 0-2; OR: 2.20; CI:1.52-3.19;P<0.0001). Further subgroup analysis based on the presence of microsphere revealed that it is safe (OR of sICH: 1.18; CI:0.433.24;P=0.75) and effective (OR of CR: 2.61; CI: 1.36-4.99;P=0.004). Subgroup analysis based on sonolysis revealed to be safe and effective. CONCLUSIONS: This novel treatment appears safe and effective. The evidence of microsphere as an enhancement of sonothrombolysis is evolving.

Correlations between MR and endothelial hyperplasia in low-grade gliomas.

PURPOSE: To investigate the capacity of multimodal MR to detect endothelial hyperplasia (EH), which has been linked to the aggressiveness of gliomas and which is so far only detected by biopsy, an invasive technique that prevents repeated measurements and early detection. MATERIALS AND METHODS: A total of 26 patients with low-grade gliomas participated in the study. All underwent a histopathological analysis and a multimodal MR examination (spectroscopic, anatomic, diffusion, perfusion, and postcontrast imaging). RESULTS: EH was present (EH+) in 15 patients and absent (EH-) in 11. No differences were observed between EH- and EH+ groups when comparing spectroscopic and diffusion parameters. Perfusion measurements, however, allowed us to distinguish EH+ from EH-: the relative regional cerebral blood flow (rCBF) was found equal to 3.23 +/- 2.05 for EH+ and 1.33 +/- 0.46 for EH- (P = 0.006). CONCLUSION: We have observed a strong correlation between the presence of EH and the increase of rCBF. Compared to conventional imaging, MR perfusion provides additional and complementary information that may be used for biopsy guidance, early detection of tumor aggressiveness, and noninvasive follow-ups.

Noninvasive diagnostic assessment of brain tumors using combined in vivo MR imaging and spectroscopy.

To determine the potential value of multimodal MRI for the presurgical management of patients with brain tumors, we performed combined magnetic resonance imaging (MRI) and proton MR spectroscopy (MRS) in 164 patients who presented with tumors of various histological subtypes confirmed by surgical biopsy. Univariate statistical analysis of metabolic ratios carried out on the first 121 patients demonstrated significant differences in between-group comparisons, but failed to provide sufficiently robust classification of individual cases. However, a multivariate statistical approach correctly classified the tumors using linear discriminant analysis (LDA) of combined MRI and MRS data. After initial separation of contrast-enhancing and non-contrast-enhancing lesions, 91% of the former and 87% of the latter were correctly classified. The results were stable when this diagnostic strategy was tested on the additional 43 patients included for validation after the initial statistical analysis, with over 90% of correct classification. Combined MRI and MRS had superior diagnostic value compared to MRS alone, especially in the contrast-enhancing group. This study shows the clinical value of a multivariate statistical analysis based on multimodal MRI and MRS for the noninvasive evaluation of intracranial tumors.

Dominant form of vanishing white matter-like leukoencephalopathy.

Leukoencephalopathy with vanishing white matter syndrome (childhood ataxia with central nervous system hypomyelination/vanishing white matter disease) is an autosomal recessive disorder characterized by the occurrence of acute episodes of deterioration after minor head trauma or infection, and symmetrical demyelination on magnetic resonance with cavitation aspects. Mutations in each of the five subunits of eIF2B have been identified. We report in an affected man and his mother an adult-onset form of childhood ataxia with central nervous system hypomyelination/vanishing white matter disease-like disorder with no mutations in the EIF2B genes and normal guanine nucleotide exchange factor eIF2B activity, suggesting a new dominant inheritance of this syndrome that may involve other genes.

Magnetic resonance spectroscopy study of glycine pathways in nonketotic hyperglycinemia.

Nonketotic hyperglycinemia is a life-threatening disorder in neonates characterized by a deficiency of the glycine cleavage system. We report on four cases of the neonatal form of the disease, which were investigated by in vitro(1)H magnetic resonance spectroscopy of blood and cerebrospinal fluid, and in vivo(1)H magnetic resonance spectroscopy of brain. The existence of glycine disposal pathways leading to an increase in lactate in fluids and creatine in fluids and brain was demonstrated. This is the first observation of elevated creatine in brain in nonketotic hyperglycinemia. A recurrent decrease of glutamine and citrate was observed in cerebrospinal fluid, which might be related to abnormal glutamine metabolism in brain. Finally, the cerebral N-acetylaspartate to myo-inositol-glycine ratio was identified as a prognostic indicator of the disease.

[Contribution of magnetic resonance spectrometry to the diagnosis of intracranial tumors]. / Apports de la spectrométrie par résonance magnétique dans le diagnostic de nature des processus occupants intracrâniens.

Magnetic resonance spectroscopy (MRS) is a method enabling the analysis of the tissue metabolic content. It may offer a more accurate diagnosis of the intracranial tumors than conventional MRI sequences. MRS of normal brain parenchyma displays 4 main metabolites: N-acetyl aspartate (neuronal marker), creatine (cellular density marker), choline (membrane activity marker) and myoinositol (glial marker); pathological processes lead to variations of the level of these metabolites and/or the appearance of abnormal metabolites (lactate), following different patterns according to pathological process involved: glioma, meningioma, metastasis, bacterial or toxoplasmic abscess, radionecrosis. The potential clinical use of this method includes positive, differential and etiological diagnosis of tumors, determination of the level of malignancy of gliomas, screening for tumor recurrence following treatment. Our laboratory has been performing MR spectroscopic explorations of brain tumors for many years. Based on this experience, we show how MRS can be routinely performed in the clinical setting, what are its limitations and potential, and what kind of information can be supplied to the clinician.