Neuroradiology
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Comparative Study Controlled Clinical Trial
Distant metastases and synchronous second primary tumors in patients with newly diagnosed oropharyngeal and hypopharyngeal carcinomas: evaluation of (18)F-FDG PET and extended-field multi-detector row CT.
Patients with oropharyngeal or hypopharyngeal squamous cell carcinoma (SCC) have a high risk of having distant metastases or second primary tumors. We prospectively evaluate the clinical usefulness of (18)F-fluoro-2-deoxyglucose positron emission tomography ((18)F-FDG PET), extended-field multi-detector computed tomography (MDCT), and their side-by-side visual correlation for the detection of distant malignancies in these two tumors at presentation. ⋯ (18)F-FDG PET and extended-field MDCT had acceptable diagnostic yields for detection of distant malignancies in untreated oropharyngeal and hypopharyngeal SCC. (18)F-FDG PET was 1.5-fold more sensitive than MDCT, but had more false-positive findings. Their visual correlation improved the diagnostic accuracy, treatment planning, and prognosis prediction.
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Controlled Clinical Trial
Perfusion-weighted MRI to evaluate cerebral autoregulation in aneurysmal subarachnoid haemorrhage.
The aim of this study was to evaluate autoregulatory mechanisms in different vascular territories within the first week after aneurysmal subarachnoid haemorrhage (SAH) by perfusion-weighted magnetic resonance imaging (PW-MRI). For this purpose, regional cerebral blood flow and volume (rCVF and rCBV) were measured in relation to different degrees of angiographically visible cerebral vasospasm (CVS). ⋯ PW-MRI showed simultaneous decrease of rCBF and rCBV in patients with SAH. The fact that rCBV did not increase in territories with CVS to maintain rCBF reveals dysfunctional vascular autoregulation. Vasospasms in the microvasculature are most evident in the basal ganglia, showing decreased rCBV and rCBF even in SAH patients without CVS.
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Approximately 20-30% of the patients with acute ischemic stroke do not have any occlusion demonstrated on initial digital subtraction angiography (DSA). We sought to determine the risk and rates of cerebral infarction and favorable neurological outcome in this group of acute ischemic stroke patients. ⋯ Ischemic stroke patients without arterial occlusion on DSA have a higher risk of cerebral infarction and disability particularly in men, patients over 65 years of age and with NIHSS >or=10. The cause of infarction may have been arterial obstruction with spontaneous recanalization or small vessel occlusion not visible on DSA.