數位放射影像(DR)系統之多重頻率處理(MLT)於胸腰椎攝影之探討

The Application of MET (Multiobjective Frequency Processing) in T-L Spine Examination Using Digital Radiography System

吳明誠(Ming-Cherng Wu) ； 蔡明倫(Ming-Lun Tsai) ； 林森富(Sen-Fu Lin) ； 潘廣澤(Kuang-Tse Pan) ； 洪建福(Chien-Fu Hung)

《中華放射線技術學雜誌》 29卷1期 (2005/06) Pp. 105-111

https://doi.org/10.30045/CJRT.200506.0012

摘要

在放射線常規攝影中，當被照體與相鄰物質的放射線衰減係數相差過大（如胸腰椎間）時，往往造成影像對比過高。傳統上我們使用楔形濾片作為補償：在數位化影像的使用中，除了利用傳統之楔形濾片的方法進行補償，亦可使用數位影像處理技術修正。本文主要探討以數位影像處理技術（多重頻率處理；Multiobjective Frequency Processing, MFP）應用於胸腰椎間高對比之修正，它是透過空間頻率強化與動態範圍調整來完成，使影像在強化中自然地顯現，並依診斷目的提供適合的可視範圍。最後，將原本對比過高的影像拉近對比（像素值）並保留其細微構造部分，進而提升影像品質。

關鍵字

數位放射影像 ； 多重頻率處理 ； 動態範圍

並列摘要

In the routine radiography, the image with high contrast may occur while the imaged object and neighboring structure result in a dramatic difference in attenuation coefficient (such as the difference between T-L spine). Conventionally we use wedge filter to be the compensator. With the utility of digital image we also can apply digital image processing technique to correct the image beside the utility of conventional wedge filter to compensate. This article emphasize the research of image processing technique (Multiobjective Frequency Processing, MFP) applied to correct the high contrast between T-L spine. This technique is completed by spatial frequency process and dynamic range control process. It provide the visible range for diagnostic purpose and improve the image automatically. Eventually, we decrease the difference in the contrast (pixel value) of the original image which is high contrast and retain the fine structure of the original image to promote the image quality.

並列關鍵字

Digital Radiography ； Multiobjective Frequency Processing ； Dynamic range