[Left mesiotemporal lesions and anterograde memory impairement: a case of neurosyphilis]. / Lésions mésiotemporales gauches et amnésie antérograde: un cas de neurosyphilis.

INTRODUCTION: Neurosyphilis has become uncommun in the developed countries. OBSERVATION: We report a case of neurosyphilis with limbic presentation, left mesiotemporal lesions on MRI and severe anterograde amnesia. DISCUSSION: Pathogeneses of MRI findings are unknown. We suggest the implication of arteritis wich affects small vessels, parenchymatous and excitotoxic lesions. The absence of mesiotemporal lesion in immunodeficient patients, the limbic systematization of pathology underlines the involvement of probably auto-immune process. Neurosyphilis should always be considered in the differential diagnosis of limbic encephalitis in order to initiate treatment and to prevent cognitives sequelaes. At last, partial status epilepticus should be diagnosed and excitotoxicity lesions prevents with antiepileptic treatment.

[Imaging of cranial gunshot traumas]. / Imagerie des traumatismes crâniens par arme à feu.

Cranial traumas from gunshot wounds are characterised by the impact of a high velocity projectile. There are therefore serious, life threatening traumas. CT Scan is essential in the emergency setting for initial evaluation of traumatic bone and parenchymatous injuries to determine the indication for neurosurgery and appropriate medical management. In case of survival, CT Scan and MRI can be used to monitor progress and any possible complications, in particular vascular or infectious complications which are specific to this type of injury.

Posterior reversible encephalopathy syndrome: a case of unusual diffusion-weighted MR images.

Posterior reversible encephalopathy (PRES) represents an uncommon entity related to multiple pathologies, the most common of which is hypertensive crisis. PRES is classically characterized as symmetrical parieto-occipital edema, but may affect other areas of the brain. Diffusion-weighted magnetic resonance imaging (DWI) is important for differentiating between vasogenic and cytotoxic edema. We present here the case of a 43-year-old woman, known to suffer from arterial hypertension and severe renal failure, who developed PRES with restricted apparent diffusion coefficients (ADC) in various cerebral areas, suggesting irreversible tissue damage. Nevertheless, follow-up cranial MRI revealed complete remission, indicating that restricted diffusion does not always lead to cell death in this pathology. The underlying pathophysiological mechanism is not well understood. Such reversibility of diffusion anomalies has already been reported with transient ischemia, vasospasm after subarachnoid hemorrhage and epilepsy but, to our knowledge, never before in PRES.

Giant cystic widening of Virchow-Robin spaces: an anatomofunctional study.

We describe 2 patients with unusual white matter cystic dilations, which could correspond to widening of the perivascular spaces. They underwent morphologic MR imaging with tractography, functional MR imaging (fMRI), and neuropsychological evaluation. fMRI examination showed no functional reorganization of cortical areas. Tractography showed an apparent decrease of white matter tract vectors into the regions of concern. Findings of the neuropsychological examination were normal. It seems that even an extensive cystic dilation of white matter does not deteriorate brain function.

Effect of metoclopramide on maternal and fetal hyperprolactinemia.

To investigate the effect of metoclopramide (MET), a dopaminergic antagonist drug, on serum PRL concentration in maternal and cord blood (CB) serum, the drug was injected in 94 at term pregnant women whereas 28 mothers received saline. Maternal serum (MS) samples were obtained before MET injection and at the parturition time. According to the interval of time between MET administration and birth, MS specimens were grouped in 7 groups. CB was obtained from neonates whose mothers were injected with saline, group 0 and from newborns whose mothers were treated with MET, groups 1 to 7. In the 7 groups of women the mean PRL concentration before MET ranged between 307 and 439 ng/ml. After MET injection a significant increase has been observed in all groups with a minimum and maximal mean value of 639 and 931 ng/ml. The highest net increment of PRL has been measured in group 1 sampled at 5 to 30 minutes after MET. CB PRL concentration in group 0, saline treated, was not different from the values measured in group 1 to 7, treated groups, with a range between 504 and 703 ng/ml. These findings suggest that maternal lactotropes are still responsive to MET. On the opposite, fetal pituitary does not release PRL after MET injection probably because PRL secretory activity is maximal or because the dopaminergic receptors' system is still immature.