自動管電流調控技術下全腹部電腦斷層掃描對於骨盆區劑量評估

The Dose Assessment for the Pelvic Area during Whole Abdominal Computed Tomography with Automatic Tube Current Modulation Technique

蘇峯毅(Feng-Yi Su) ； 陳東明(Tung-Ming Chen) ； 林智勝(Chih-Sheng Lin) ； 陳瑞芬(Jui-Fen Chen) ； 何永仁(Yung-Jen Ho) ； 陳俊光(Chun-Kuang Chen)

《中華放射線技術學雜誌》 36卷4期 (2012/12) Pp. 186-192

https://doi.org/10.30045/CJRT.201212.0003

摘要

電腦斷層掃描貢獻約50 %的醫療曝露之群體劑量，適當使用自動管電流調控技術可合理抑低受檢者的有效劑量，本研究探討在管電流調控技術下全腹部電腦斷層掃描可能給於骨盆區過高輻射劑量，依據ICRP87號報告指出，腹部與骨盆的掃描，通常有使用相同管電流的慣例，骨盆區掃描管電流若降低至腹部區管電流的1/3，可達成有效影像診斷品質，而實際減低劑量的可能性，本實驗結論顯示可減少高達39 %有效劑量。依臨床全腹部掃描資料評估顯示，自動管電流調控技術在大部份病人中，骨盆區因衰減較高其管電流比腹部區高。因此我們推論在管電流調控技術下全腹部電腦斷層掃描給於骨盆區過高輻射劑量，其存在降低受檢者有效劑量的可行性。

關鍵字

電腦斷層掃描 ； 自動管電流調控技術 ； 有效劑量

並列摘要

Computed tomography has contributed about 50% of the collective dose from medical exposure, appropriate using automatic tube current modulation technique can reasonably lower the patients' effective dose. This study analyze the possibility that pelvic region receives high radiation dose during whole abdominal computed tomography with auto tube current modulation technique. Base on Annals of the ICRP 87, it is a common practice to use the same current tube whenever abdomen and pelvis are to be scanned. Substantial dose reduction, without any recognizable deterioration in diagnostic image quality, may be achieved if pelvic CT is performed at almost one-third. In this study, we can reduce the effective dose up to 39% less. The clinical whole abdomen scanning parameters evaluation shows that the automatic tube current modulation technique gives higher tube current in pelvic region due to its higher attenuation than abdomen region in most patients. This implies that the computed tomography gives high radiation dosage to the pelvic region hence the possibility of lowering recipients' effective dosage.

並列關鍵字

computed tomography ； automatic tube current modulation ； effective dose