Perfusion, diffusion et spectroscopie RMN dans les gliomes cérébraux

TOULOUSE3-BU Sciences (315552104) / SudocSudocFranceF

Corrélations entre anatomopathologie et IRM de diffusion et de perfusion dans les gliomes de grade II et III

Nous avons analysé 28 corrélations anatomoradiologiques chez 21 patients porteurs de gliomes de grades II et III. Volumes sanguins cérébraux et coefficients apparents de diffusion en IRM ont été mesurés sur des sites précis des lésions. Les densités cellulaire et vasculaire ont été mesurées par un logiciel automatisé après immunomarquage et ces résultats ont été corrélés aux données des séquences de perfusion et de diffusion. Les mesures du volume sanguin cérébral et du coefficient apparent de diffusion sont des éléments discriminants dans l'évaluation initiale du grade tumoral d'un gliome et sont plus informatives que la prise de contraste. Ceci est particulièrement vrai pour les oligodendrogliomes, lésions ayant une composante vasculaire intrinsèque importante. De plus, les anomalies en perfusion et diffusion sont associées à l'hypervascularisation et à l'hypercellularité observées en anatomopathologie. Ces nouvelles séquences IRM pourraient participer aux décisions de prise en charge des patients porteurs de gliomes, voire dans de futures classifications anatomoradiologiques.TOULOUSE3-BU Santé-Centrale (315552105) / SudocPARIS-BIUM (751062103) / SudocSudocFranceF

Decreased frontal white-matter diffusion and improved cognitive flexibility after burr-hole surgery in moyamoya angiopathy

International audienceBackground: In Moyamoya Angioplasty (MMA), increased apparent diffusion coefficient (ADC) in frontal white matter (WM) with a normal appearance has been associated with frontal hypoperfusion and executive dysfunction. Multiple burr-hole surgery enables the revascularization of large frontal areas.Goal: To assess the effect of multiple burr-hole surgery on the ADC and cognitive functions in adults with MMA.Methods: ADC was measured in 26 brain hemispheres of 14 consecutive adults with MMA (9 women, mean age ± SD: 38.1 ± 10.7 years) prior to and 6 months after burr-hole surgery. ADC was obtained from regions of interest located in frontal and posterior (temporo-occipital) normal-appearing WM. Ten patients had neuropsychological assessment that focused on executive and attentional functions before and after surgery.Results: Anterior and posterior ADC values did not differ before surgery (815.8 ± 60.1 vs. 812.1 ± 35.3 mm2/s, p = 0.88). After surgery, frontal ADC was lower than prior to surgery (789.9 ± 64.5 vs. 815.8 ± 60.1 mm2/s; p <0.001) whereas no change occurred in posterior ADC (p = 0.31). Trail-making test part B median z-score increased from - 1.47 to - 0.21 (p = 0.018), suggesting improved cognitive flexibility.Conclusion: In adults with MMA, indirect revascularization with burr-hole is followed by a decrease of ADC in normal-appearing frontal WM and may have improved some executive functions in the flexibility process. Change in ADC may reflect the improvement in cerebral perfusion after surgery. The measuring of ADC may be a promising tool in exploring potentially reversible microstructural WM damage related to hypoperfusion and cognitive change in MMA

Should CT angiography of the supra-aortic arteries be performed systematically following attempted suicide by hanging?

International audiencePurpose: Characterize and determine the frequency of dissections of the supra-aortic arteries (SAA) and injuries to the cervical spine and pharyngolaryngeal cartilages viewed on CT scans after an attempted suicide by hanging.Materials and methods: A retrospective, single-centre study of all patients admitted for attempted suicide by hanging between January 2010 and June 2017 who received CT angiography of the SAA. Search for signs of dissection of the cervical arteries and injuries to the brain, spinal column and pharyngeal and laryngeal cartilages. The results were compared with the initial clinical severity, which was assessed indirectly by whether patients were initially admitted in an intensive care unit (ICU) or in an emergency department (ED).Results: Out of 162 patients included, 4 presented with SAA dissection (2.5%), comprising 3 vertebral arteries and 1 external carotid artery. The cases in question were of 4 men, all in cardiac arrest on arrival and all were treated in ICU. Of the most serious cases, 18/72 (25%) had anoxia-related injuries and one also presented with a C2 fracture. No vascular lesions or signs of cerebral anoxia were observed in the 90 ED patients. Nevertheless, pharyngeal and laryngeal fractures were observed in both groups, with no significant difference.Conclusion: In our study, 2.5% of CT angiograms performed after an attempted hanging revealed SAA dissection. Crucially, only most severe patients, who have been immediately admitted to ICU suffered SAA. These results call into question the systematic indication of this exam in cases of hanging attempts

Evaluation of the Lactate-to-N-Acetyl-aspartate Ratio Defined With Magnetic Resonance Spectroscopic Imaging Before Radiation Therapy as a New Predictive Marker of the Site of Relapse in Patients With Glioblastoma Multiforme

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