The Imaging Method And Diagnosis Research Of Intracranial Tuberculosis With MSCT

Background:To explore whether the diagnosis of intracranial tuberculosis (TB) can be improved when multi-slice computed tomography (MSCT) scans are taken with a delay of five minutes after contrast media application.Material and Methods:Pre-and post-contrast CT scans of the head were obtained from30patients using a16-slice spiral CT. Dual-phase acquisition was performed immediate and five minutes after contrast agent injection. Diagnostic value of the different images were compared using a score system applied by two experienced radiologists.Results:Five hundred twenty six lesions in30patients were found (22meningeal thickening;235meningeal tuberculoma/tubercle;269parenchymal tuberculoma/tubercle). Images obtained with five minutes delayed scan time were superior in terms of lesion-size and meningeal thickening outlining in all disease types (P<0.01). It also improved the ability to distinguish between vascular sections from the cerebral sulcus and tubercle (P<0.01).Conclusions:Image acquisition with five minutes delay after contrast agent injection should be performed as a standard scanning protocol to diagnose intracranial TB. Objective To assess the clinical application of iterative reconstruction (IR) in the head and neck CT angiography (CTA). Methods100patients who underwent the head and neck CTA examination were divided into group A and group B at random. Each group included50patients. Group A was performed the conventional-dose scan method (tube voltage120kV, tube current300mAs), and images were reconstructed with filtered back projection (FBP); Group B was performed the low-dose scan method (tube voltage100kV, dynamic tube current (199～399mAs)), and images were reconstructed with IR. Two experienced radiology physicians reviewed the results of image quality using double blind method, and compared CT dose index volume (CTDIvol) and dose-length product (DLP). Results There were significant differences between radiation dose and image quality of the two groups (P<0.001). Radiation dose of group B was significantly lower than that of group A, while image quality of group B was significantly better than that of group A. Conclusion In the head and neck CTA applications, compared with FBP, using IR reconstruction can reduce radiation dose and improve image quality.