产科三维超声显像

Three-Dimensional Ultrasonography in Obstetrics

最近,三维(3D)超声显像(US)已进入临床实践,产科是其一个主要的应用领域。虽然胎儿和胎盘的各种先天性疾病能用常规(2D)US论断,但在获得适当的切面影像或产生“胎儿体表”确切印象方面却常遇到困难,且冗长费时。3DUS方法产生容积数据库,在此容积内,可提取任何平面,获得2DUS达不到而又关键的观察面影像,其扫查的解剖结构可以交互操作的方式显示,并从三个互相垂直的平面同时观察。另外,容积数据可重建为结构的体表像,此种功能2DUS做不到。3DUS临床应用的有效性依赖于对获得的立体数据的适当处理和显示。 当前可选显示方式有:①任意平面像;②突出软组织和骨骼的体表重建像;③应用液晶或红/蓝眼镜进行立体观察;④选通数据资料电影回放;⑤实时处理3DUS。 容积数据产生影像的旋转在了解或领会解剖结构时是重要的,旋转角范围视临床情况而定。另外,随着观察量的增加需要存储更多数据。

Abstract: Three - dimensional(3D) ultrasonography(US)has recently been introduced into clinical practice. Ob-stetrics is one of the major fields for 3DUS applications.Although various congenital diseases of the fetus and pla-centa can diagnosed by conventional (2D) US, but it is of-ten difficult and tedious to obtain US images in the appro-priate plane or to develop the correct impression of the'fetal surface'. 3DUS Methods produce a volume data set. Withinthe volume, images can be extracted in any desired plane,providing the possibility of obtaining critical views notachievable with conventional (2D) US. The scannedanatomy also can be interactively displayed with simulta-neous viewing of orthogonal sectional slices. In addition,volume data may be rendered to show an image of the sur-face of the structure, this can't be done with conventionalimaging. The clinical efficiency of 3DUS imaging dependson adequate handling and display of the acquired datacube. Current display option modes include: (1 ) arbitraryplanar images; (2)surface rendering with emphasis on softtissues or skeletal detail; (3) stereo viewing using liquidcrystal glasses or red/blue glasses; (4)cine review of gat-ed studies; (5) real - time processable 3DUS. Rotation ofvolume data also is important in understanding or compre-hending structural anatomy. The range of rotation anglesvaries depending on the clinical setting. Also data storagerequirements increase as the number of views increases.