Cittadini G, Conzi R, Motta G
Istituto di Radiologia, Università degli Studi di Genova.
Chir Ital. 1995;47(3):13-7.
Spiral or helical technology is a new computed tomographic technique based on the continuous acquisition of volumetric CT data during continuous x-ray beam rotation and continuous patient transportation at constant velocity. It has many advantages over conventional CT: the authors briefly review the basic principles of spiral CT and discuss the applications and the possible advantages in the assessment of lung cancer. The most important characteristics of spiral CT are rapid image acquisition, allowing a single-breath-hold scan of the lung, and the ability to obtain axial image reconstructions at arbitrary and overlapping intervals, thus allowing the detection of small lesions that otherwise would be inconspicuous because of respiratory misregistration or partial volume averaging. This leads to better identification of small pulmonary nodules and to high quality multiplanar reconstructions that can be useful in the study of mediastinal lymph nodes and the vascular and tracheobronchial spreading of lung cancer. Many of the spiral CT scanners allow for 40 sec extended spiral acquisition during a single-breath-hold, permitting the evaluation of the thorax and the upper abdomen. This usually includes the adrenals and the whole liver, thus allowing a rapid staging of thoracic neoplasms, with an accuracy higher than that of conventional CT.
螺旋技术是一种新的计算机断层扫描技术，它基于在X射线束连续旋转以及患者以恒定速度连续移动的过程中持续采集容积CT数据。与传统CT相比，它具有许多优势：作者简要回顾了螺旋CT的基本原理，并讨论了其在肺癌评估中的应用及可能的优势。螺旋CT最重要的特点是图像采集速度快，能够在一次屏气期间对肺部进行扫描，并且能够以任意和重叠的间隔获得轴向图像重建，从而能够检测出那些因呼吸配准错误或部分容积平均效应而原本难以发现的小病变。这有助于更好地识别小的肺结节，并获得高质量的多平面重建图像，这些图像在研究纵隔淋巴结以及肺癌的血管和气管支气管扩散方面可能会很有用。许多螺旋CT扫描仪允许在一次屏气期间进行40秒的扩展螺旋采集，从而能够对胸部和上腹部进行评估。这通常包括肾上腺和整个肝脏，从而能够快速对胸部肿瘤进行分期，其准确性高于传统CT。
