256 Slices CT Scan 256 多切面電腦掃描

The advanced imaging capability of the SOMATOM definition Flash Siemens’256 slices CT scanner allows good quality coronary artery images to be captured at much lower radiation doses even in the presence of high heart rates or arrhythmia.

Setting new standards for speed and dose reduction, the SOMATOM Definition Flash requires only a fraction of the radiation dose that systems previously required to scan even the tiniest anatomical details faster than ever before. The SOMATOM Definition Flash is a new dual-source CT,featuring two X-ray tubes that simultaneously revolve around the patient’s body. The fastest scanning speed in CT (i.e., 43 cm/s) and a temporal resolution of 75 ms, enable for example complete scans of the entire chest region in just 0.6 seconds. Thus, patients are no longer required to hold their breath during the exam the way they had in the past. At the same time, the SOMATOM Definition Flash operates at an extremely reduced radiation dose. For example,

a spiral heart scan can be performed with less than 1 millisievert (mSv), whereas the average effective dose required for this purpose usually ranges from 8 mSv to 40 mSv.

This new generation of dual-source CT scanners, featuring two X-ray tubes and two detectors, will provide a genuine innovation boost to dual-source technology. The enormous speed of the SOMATOM Definition Flash offers decisive advantages, especially regarding examinations of moving structures, such as the thorax and the heart. The gantry (i.e., the X-ray detector system surrounding the bore) rotates about its own axis in just 0.28s. It is this extraordinary rotational speed that enables a scan speed never before attained in CT (i.e., up to 43 cm per second) and temporal resolution of 75 milliseconds. The patient is moved through the CT tube more than twice as fast as with any conventional system. At the same time, scans acquired with the SOMATOM Definition Flash require a much lower radiation dose than conventional scans. While the average effective dose for a heart CT scanner ranges from 8 mSv to 40 mSv, the new CT scanner gets by with less than 1 mSv. In comparison: The X-ray radiation that everyone is exposed to each year from natural sources amounts to 2 mSv to 5 mSv. The dose values of the new CT scanner, thus lie far below those of an intracardiac catheter examination, thus opening up possibilities for using CT scanners for routine cardiological examinations.

西門子高速 256 排炫速雙源螺旋電腦掃描儀、以高速掃描、徹底克服心跳過快或心律不整所造成的欠佳效果、 以更低的輻射劑量能顯示更清晰影像。全新電腦掃描系統  SOMATOM Definition Flash，其掃描速度之快與輻 射劑量之低，遠勝市面同類電腦掃描系統。系統只需傳統輻射劑量的一小部分，就能以前所未有的速度完成最細微組織結構的造影。SOMATOM Definition Flash 屬全新雙源電腦掃描系統，具備兩個同時旋轉的 X 射線球管，43cm/s 的極快電腦掃描速度和 75ms 的時間分辨率，令全胸掃描全程僅需 0.6 秒，讓患者無須再在電腦檢查過程中閉氣。此外，SOMATOM Definition Flash 令輻射劑量大幅降低：心臟螺旋掃描只需少於 1 mSv 的 劑量﹔常規多層心臟電腦掃描的平均有效劑量為 8 mSv 至 40 mSv。

這種新一代雙源電腦掃描系統具備兩個 X 射線管和兩個探測器，其創新技術將雙源電腦掃描技術推向新的高度。 SOMATOM Definition Flash 超高的掃描速度可為臨床帶來決定性優勢，尤其是在檢查胸腔和心臟等器官 時，機架只需 0.28 秒即可旋轉一圈，配合全新的 Flash 掃描模式，達致前所未有的電腦掃描速度（高達 43cm/s） 和時間分辨率（75ms），其掃描速度比目前最快的電腦掃描還快 2 倍。同時 SOMATOM Definition Flash 掃描所產生的輻射劑量亦遠遠低於傳統電腦掃描儀，常規電腦心臟掃描所需的平均有效劑量為 8 mSv 至 40 mSv， 新系統則只需不足 1 mSv，不但低於天然本底輻射（每人每年接受的來自自然界的 X 射線輻射，通常為 2 mSv 至 5 mSv），也低於 DSA 心導管檢查輻射劑量，讓心臟電腦掃描進入臨床常規。