What effective technique to differentiate radiation brain necrosis from a tumor progression in patients treated with radiation: A monocentric retrospective study combining the MRI TRAMs technique and the (18F)-dopa PET/CT.

PURPOSE: Brain necrosis after radiotherapy is a challenging diagnosis, since it has similar radiological appearance on standard MRI to tumor progression. Consequences on treatment decisions can be important. We compare recent imaging techniques in order to adopt a reliable diagnostic protocol in doubtful situations. PATIENTS AND METHOD: This is a retrospective study comparing the performance of three imaging techniques after radiotherapy of brain metastasis: Perfusion-MRI, TRAMs technique and F-dopa PET-CT. The evolution of the treated metastasis volume was also analyzed by contouring all patients MRIs. All included patients were suspected of relapse and had the three exams once the volume of treated metastasis increased. RESULTS: The majority of our patients were treated by stereotactic radiotherapy. Suspicion of relapse was on average around 17months after treatment. Four cases of radionecrosis were diagnosed and six cases of real tumor progression. Neurological symptoms were less present in radionecrosis cases. All of our radionecrosis cases had relative cerebral blood volume below 1. F-dopa PET-CT succeeded to set the good diagnosis in eight cases, although we found one false positive and one false negative exam. The TRAMs technique failed in one case of false negative exam. CONCLUSIONS: Perfusion-MRI showed high performance in the diagnosis of radionecrosis, especially when calculating relative cerebral blood volume rate. The TRAMs technique showed interesting results and deserves application in daily routine combined with the perfusion-MRI. F-dopa CT might induce false results because of different metabolic uptake according to tumor type, medication and brain blood barrier leak.

Anterior ischemic stroke: Comparison of two clinical outcome prediction scores through the investigation of cerebral collaterals using multiphase CT angiography.

PURPOSE: To compare the evaluation of collaterals on multiphase computed tomography (CT) angiography using the score proposed by the reference study by Menon et al. and the Alberta Stroke Program Early CT (ASPECT) score for the prediction of favorable clinical outcome in patients with anterior ischemic stroke (IS). MATERIALS AND METHODS: Retrospective single center study including 199 patients with anterior ischemic stroke and evaluated using multiphase CT angiography. Collaterals were assessed using the reference score and ASPECT score. The early clinical outcome [National Institute of Health Stroke Score (NIHSS) over day 1] and later clinical outcome [90-day modified Rankin Scale (mRS)] were collected. The primary analysis related to the association between collateral scores and clinical outcome. RESULTS: Collaterals are an independent predictive factor of favorable clinical outcome with the two scores, ranging from an odds ratio (OR) [95% confidence interval (CI)] = 1.84 [1.23; 2.76], P = 0.003 for the reference score to an OR [95% CI] = 2.63 [1.21; 5.73], p = 0.015 for the phase 3 ASPECT score. The phase 3 ASPECT score offers better sensitivity (Se) for the prediction of a favorable clinical outcome [Se = 95%, specificity (Sp) = 37% for a threshold of 7/7] than the reference score (Se = 83%, Sp = 47% for a threshold of 4/5). CONCLUSION: This study demonstrates the value of the ASPECT score in analyzing collaterals using multiphase CT angiography for the prediction of clinical outcome.

Subacute corticobasal syndrome following internal carotid endarterectomy.

The present report is of two patients who, immediately after internal carotid endarterectomy, presented with unexplained hemiplegia, despite normal findings on repeated MRI scans, which secondarily evolved into homolateral subacute corticobasal syndrome (CBS), with asymmetrical hemispheric hypometabolism and evidence of dopaminergic denervation. This prompted us to propose an hypothesis of transient cerebral hypoxia arising during the surgical clamping period that might have provoked a prolonged or permanent functional lesion of the left hemisphere and basal ganglia, with no visible infarction on MRI but only synaptic rearrangement of the neural networks, thereby revealing or exacerbating a potentially preexisting silent impairment.

[A new area for radiotherapy with favourable features]. / Une nouvelle ère pour la radiothérapie avec des avancées prometteuses.

Radiotherapy is a complex medical speciality involving technology research, biology research and clinical research. All these basic researches are performed in order to optimise the management of cancer treatment patients. The aim of the present review is to present radiotherapy as a moving speciality whatever the concerned section. It will be particularly described the new approaches in terms of technology but also clinical developments.