Casselman J W, Kuhweide R, Ampe W, Meeus L, Steyaert L
Department of Radiology, A. Z. St.-Jan Brugge, Belgium.
AJNR Am J Neuroradiol. 1993 Jan-Feb;14(1):59-69.
To assess the value of unenhanced T1-weighted images, T2-weighted images, gadolinium-enhanced T1-weighted images, and three-dimensional Fourier transformation-constructive interference in steady state (3DFT-CISS) images in depicting lesions of the membranous labyrinth.
Six patients were studied using 1-T MR; both enhanced (gadolinium-tetraazacyclododecane tetraacetic acid) and unenhanced images were obtained and different sequences compared to determine which provided the most information.
A combination of gadolinium-enhanced T1-weighted and 3DFT-CISS images could depict all membranous labyrinth pathology. Unenhanced T1-weighted images were necessary to exclude spontaneous hyperintensity in the membranous labyrinth. Gadolinium-enhanced T1-weighted images were needed to detect enhancing pathology such as labyrinthitis and tumors inside the membranous labyrinth. In these cases, 3DFT-CISS images allowed immediate differentiation between inflammation and tumor. In temporal bone tumors involving the bony and membranous labyrinth, unenhanced and enhanced T1-weighted images often sufficed to suggest the correct diagnosis. Only 3DFT-CISS images were able to demonstrate small structures (as fistulas) and to help us confirm or rule out obliteration of the labyrinthine fluid spaces. 3DFT-CISS images were necessary to detect small congenital malformations of the membranous labyrinth when only MR was performed. Uncalcified obliteration of the labyrinth fluid spaces could be reliably detected only on 3DFT-CISS images. Here also gadolinium-enhanced T1-weighted images had to be obtained because enhancement of the soft tissues inside the membranous labyrinth had been observed.
The CISS sequence and enhanced T1-weighted sequence formed the best sequence combination for diagnosis of membranous labyrinth lesions; additional, unenhanced T1-weighted images can help one differentiate labyrinthitis, proteinaceous fluid, subacute hemorrhage, or tumor inside the labyrinth.
评估非增强T1加权像、T2加权像、钆增强T1加权像及三维傅里叶变换稳态构成干扰(3DFT-CISS)像在显示膜迷路病变中的价值。
对6例患者采用1-T磁共振成像(MR)进行研究;获取增强(钆-四氮杂环十二烷四乙酸)及非增强图像,并比较不同序列以确定哪一种能提供最多信息。
钆增强T1加权像与3DFT-CISS像相结合能够显示所有膜迷路病变。非增强T1加权像对于排除膜迷路内的自发性高信号是必要的。钆增强T1加权像用于检测膜迷路内的强化病变,如迷路炎和肿瘤。在这些病例中,3DFT-CISS像可立即区分炎症与肿瘤。在累及骨迷路和膜迷路的颞骨肿瘤中,非增强及增强T1加权像通常足以提示正确诊断。只有3DFT-CISS像能够显示小结构(如瘘管),并帮助我们确认或排除迷路内液体间隙的闭塞。当仅进行MR检查时,3DFT-CISS像对于检测膜迷路的小先天性畸形是必要的。迷路内液体间隙的未钙化闭塞仅在3DFT-CISS像上能可靠检测到。在此同样必须获取钆增强T1加权像,因为已观察到膜迷路内软组织的强化。
CISS序列与增强T1加权序列构成了诊断膜迷路病变的最佳序列组合;此外,非增强T1加权像有助于鉴别迷路炎、蛋白性液体、亚急性出血或迷路内肿瘤。