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T1‐weighted fluid‐attenuated inversion recovery (FLAIR) sequence is a relatively new pulse sequence for intracranial MR imaging. This study was performed to compare the image quality of T1‐weighted FLAIR with the T1‐weighted FSE sequence. Twenty patients with brain lesions underwent T1‐weighted fast spin‐echo (FSE) and T1‐weighted FLAIR during the same imaging session. Four quantitative and three qualitative criteria were used to compare the two sequences after contrast. Two of four quantitative criteria pertained to lesion characteristics: lesion to white matter (WM) contrast‐to‐noise ratio (CNR) and lesion to cerebrospinal fluid (CSF) CNR, and two related to signals from normal tissue: grey matter to WM CNR and WM to CSF CNR. The three qualitative criteria were conspicuousness of the lesion, the presence of image artefacts and the overall image contrast. Both T1‐weighted FSE and FLAIR images were effective in demonstrating lesions. Image contrast was superior in T1‐weighted FLAIR images with significantly improved grey matter‐WM CNRs and CSF‐WM CNRs. The overall image contrast was judged to be superior on T1‐weighted FLAIR images compared with T1‐weighted FSE images by all neuroradiologists. Two of three reviewers considered that the FLAIR images had slightly increased imaging artefacts that, however, did not interfere with image interpretation. T1‐weighted FLAIR imaging provides improved lesion‐to‐background and grey to WM contrast‐to‐noise ratios. Superior conspicuity of lesions and overall image contrast is obtained in comparable acquisition times. These indicate an important role for T1‐weighted FLAIR in intracranial imaging and highlight its advantage over the more widely practiced T1‐weighted FSE sequence.  相似文献   
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Prefabricated, patient-specific alloplastic implants for cranioplasty reduce surgical complexity, decrease operative times, minimize exposure and risk of contamination, and have resulted in improved aesthetic results. However, in creating a prefabricated custom implant using a patient’s computed tomography data, a stable, unalterable defect must be clearly defined before surgery. In the event that an intraoperative modification of an exiting skull defect is required, or in cases of tumour resection in which the size of the skull defect is unknown preoperatively, these prefabricated implants cannot be used. The ideal method for alloplastic cranioplasty would enable cost-effective creation of a patient-specific implant with the capacity for intraoperative modification.The present article describes a novel technique of cranioplasty that uses a patient’s computed tomography data to create a custom forming tool (ie, mold), enabling intraoperative creation of a patient-specific titanium mesh implant. The utility of these implants in creating a custom reconstructive solution in cases in which the size of the skull defect is unknown preoperatively will be demonstrated using two case presentations.  相似文献   
86.
Stanley  J; Gobien  RP; Cunningham  J; Andriole  J 《Radiology》1986,158(1):195-197
Endoscopically performed biliary drainage (EPBD) is now an alternative to percutaneous biliary drainage. The morbidity, mortality, and survival statistics of 97 patients with obstructive jaundice who had undergone percutaneous transhepatic biliary drainage (PTBD) and surgery, PTBD alone, EPBD and surgery, or EPBD alone were compared. Overall, the EPBD group had fewer complications and lower mortality than the other groups. When palliative treatment of patients with malignancies was compared, the complication rates associated with EPBD and PTBD were similar; however, mortality was lower with EPBD. No negative effect on survival was found with EPBD. In addition, EPBD offered several additional advantages over PTBD, including fewer bleeding complications, better patient acceptance, and avoidance of external catheter care. EPBD should be considered as a viable alternative to PTBD. Additional studies are needed to determine whether it is to be considered the initial drainage procedure of choice in patients with obstructive jaundice.  相似文献   
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In a review of 432 children with newly diagnosed acute lymphoblastic leukemia (ALL), we identified a new nonrandom translocation, tdic(9;12)(p1?1;p1?2), in the leukemic marrow cells of eight patients. Seven had hypodiploid karyotypes that lacked chromosomes 9 and 12 and contained a der(12), tdic(9;12); the eighth had a pseudodiploid karyotype with two normal 9 chromosomes, one normal 12 and the der(12), tdic(9;12). Abnormalities involving chromosomes other than 9 and 12 were noted in four of the eight patients. All cells with the tdic(9;12) expressed both the common ALL antigen and HLA-DR. Cytoplasmic immunoglobulin, a marker of pre-B ALL, was detected in one case with the tdic(9;12) but was absent in the other seven. Our results suggest that the tdic(9;12)(p1?1;p1?2) rearrangement is specifically associated with leukemic B cell precursors.  相似文献   
89.
summary The asymmetry of condylar and rami heights was determined from Orthopantomograms® of 25 macerated skulls and compared with the results of the 'true' values obtained by direct measurements of the skulls. The correlation between the two measuring methods was low.  相似文献   
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