[Acute CSF changes in the mesencephalon aqueduct after subarachnoid hemorrhage as measured by PC-MRI]. / Caractérisation des perturbations du flux de LCS dans l'aqueduc du mésencéphale par IRM-CP à la phase aiguë de l'hémorragie méningée.

PURPOSE: Determining acute intracranial hydrodynamic changes after subarachnoid hemorrhage through an analysis of the CSF stroke volume (SV) as measured by phase-contrast MRI (PC-MRI) in the mesencephalon aqueduct. METHOD: A prospective study was performed in 33 patients with subarachnoid hemorrhage. A PC-MRI imaging study was performed n the acute phase (< 48 hours). CSF flow was measured in the aqueduct. The appearance of acute hydrocephalus (HCA) was then compared with data on CSF flow, and the location of the intraventricular and perimesencephalic bleeding. RESULTS: CSF analysis was performed on 27 patients, 11 of whom presented with an acute HCA. All 11 patients had an abnormal SV in the aqueduct: patients with a communicating HCA had an increased SV (n=8); and patients with a noncommunicating HCA had a nil SV (n=3). Patients with a normal SV in the aqueduct did not develop an acute HCA. Intraventricular bleeding significantly led to HCA (P=0.02), which was of the communicating type in 70% of cases. CONCLUSION: Subarachnoid hemorrhage leads to intracranial CSF hydrodynamic modifications in the aqueduct in the majority of patients. CSF flow can help us to understand the mechanism of the appearance of acute HCA. Indeed, hydrocephalus occurred - of the communicating type in most cases - even in the presence of intraventricular bleeding.

Diffusion tensor imaging characteristics of the corpus callosum in mild, moderate, and severe traumatic brain injury.

BACKGROUND AND PURPOSE: The corpus callosum is an important predilection site for traumatic axonal injury but may be unevenly affected in head trauma. We hypothesized that there were local differences in axonal injury within the corpus callosum as investigated with diffusion tensor imaging (DTI), varying among patients with differing severity of traumatic brain injury (TBI). MATERIALS AND METHODS: Ethics committee approval and informed consent were obtained. Ten control subjects (7 men, 3 women; mean age, 37 +/- 9 years) and 39 patients with TBI (27 men, 12 women; 34 +/- 12 years) were investigated, of whom 24 had mild; 9, moderate; and 6, severe TBI. Regions of interest were selected in the callosal genu, body, and splenium to calculate fractional anisotropy (FA), apparent diffusion coefficient (ADC), and the number of fibers passing through. Statistical comparison was made through analysis of variance with the Scheffé post hoc analysis. RESULTS: Compared with controls, patients with mild TBI investigated <3 months posttrauma (n = 12) had reduced FA (P < .01) and increased ADC (P < .05) in the genu, whereas patients with mild TBI investigated > or =3 months posttrauma (n = 12) showed no significant differences. Patients with moderate and severe TBI, all investigated <3 months posttrauma, had reduced FA (P < .001) and increased ADC (P < .01) in the genu compared with controls and reduced FA in the splenium (P < .001) without significant ADC change. CONCLUSION: Mild TBI is associated with DTI abnormalities in the genu <3 months posttrauma. In more severe TBI, both the genu and splenium are affected. DTI suggests a larger contribution of vasogenic edema in the genu than in the splenium in TBI.

[Craniocerebral gunshot wounds: a study of outcome predictors]. / Les plaies crâniocérébrales d'origine balistique: recherche d'arguments pronostiques.

BACKGROUND AND PURPOSE: A retrospective study about craniocerebral gunshot wounds was done to better identify outcome predictors. METHODS: We reported and analyzed the clinical and radiological data of 18 patients admitted to Le Kremlin-Bicêtre institute for a craniocerebral gunshot wound between January 2000 and December 2005. The Glasgow Outcome Scale (GOS) was used to analyze patient outcome. RESULTS: There were 17 men and one woman, mean age 43 years (range 17-84). Fifteen patients died, two had a GOS equal to 2 and one GOS equal to 3. There were 16 suicides and two murders. All patients with areactive bilateral mydriasis and all patients with Glasgow Coma Scale (GCS) less than seven died except one. The 10 patients with intraventricular hemorrhage died. The bullet crossed the midline for 13 patients and all of them died. None of the patients underwent emergency surgery for the treatment of craniocerebral gunshot wounds because of low Glasgow Coma Scale. CONCLUSIONS: This study shows some interesting prognosis patterns: bilateral areactive mydriasis, GCS less or equal to 7 and bullet trajectory (if crossing the midline) are the most important factors predicting a fatal outcome.

Intracranial dissemination of primary spinal cord anaplastic oligodendroglioma.

We report the first case of a 22-year-old man, with a previously neurosurgically treated intramedullary anaplastic oligodendroglioma (World Health Organization grade III), who developed 19 months later two histologically proven intracranial metastases. We support a hypothesis whereby the anaplastic parts of tumors have spread along the spinal cord and brainstem via the cerebrospinal fluid pathways, a process that could be promoted by surgical manipulation, although the relative contribution of the two factors remains speculative.

[Cerebrospinal fluid flow imaging in the meningeal hemorrhage]. / Imagerie de l'hydrodynamique cérébrale dans les hémorragies méningées.

BACKGROUND AND PURPOSES: Cerebrospinal fluid (CSF) flow oscillations are synchronized with cerebral blood flow and are also involved in the control of variations of intracranial pressure during the cardiac cycle. The aim of this study was to investigate the possible alterations of CSF flow dynamics during the acute phase of meningeal hemorrhage (MH). METHODS: Eleven patients with MH confirmed by computed tomography (CT) scan were examined by MR imaging, which comprised morphological sequences and flow dynamic sequences for quantification of CSF oscillations and cerebral blood flow rates. CSF oscillations were recorded at the cerebral aqueduct and C2-C3 subarachnoid space (SAS), where a vascular sequence was also performed to quantify artery blood flow. These results were compared to oscillations of a population of 44 control subjects and a difference of at least two standard deviation was used to define a hyperdynamic or hypodynamic appearance of CSF flow. Dilatation of the ventricular system was determined on radiographs by two neuroradiologists and a neurosurgeon. RESULTS: Only four patients presented normal ventricular CSF flow, one patient presented hypodynamic flow and five patients presented hyperdynamic flow. Five patients had normal cervical CSF flow and five patients presented hyperdynamic flow. The two patients with ventricular dilatation both presented hyperdynamic ventricular CSF flow associated with normal cervical CSF flow. One patient was excluded. CONCLUSION: Abnormal CSF flow dynamics were shown suggesting the hypothesis that bleeding increases intracranial volume and induces a reduction of cerebral compliance and an increase of intracranial pressure. The increased oscillations in the ventricular system would therefore predispose to dilatation.