flat panel detectorを用いた食道表在癌のX線診断

Diagnosis of Superficial Esophageal Cancer Using the C-arm-type X-ray Apparatus-equipped Flat Panel Detector

要旨　直接型平面検出器（FPD）は，食道造影検査において従来のDRが持つ利点，すなわち，連続撮影，リアルタイム画像表示，画像処理などの機能はそのままに，空間分解能の向上で画質も大幅に改善し良質な画像が得られる．さらに左右側への円弧動回転で任意方向からの撮影が可能なCアーム機能も搭載している．今回，当院食道表在癌症例46例を用いて従来のフィルム-増感紙による撮影系（CFSS群：26病変）とFPD群（20病変）の描出能を比較した．その結果，側面像の描出能では両群間に差はなかったが，正面像ではFPD群はCFSS群に比べ描出能が高く，境界，隆起や陥凹といった所見が鮮鋭に描出される傾向がみられた．さらに，描出困難とされるm_{1, 2}癌の正面像でもFPD群はCFSS群に比べ明らかに良好な描出成績が得られた（p＝0.03）．以上からFPDは，食道表在癌のうちより浅い浸潤癌に高い描出能を有することがわかった．

　Flat panel detector (FPD) enables us easily to detect esophageal lesions with clear depiction and offering a lot of advantages, such as sequential exposure, real-time image acquisition and image processing. The oblique radiographic technique using the movable C-arm helps to take a lateral view of the lesions. These advantages are not available when using CFSS (conventional film with an intensifying screen system). To elucidate the usefulness of FPD for X-ray diagnosis of superficial esophageal cancer, we studied the detection ability of FPD compared with that of CFSS (FPD : 20 lesions, CFSS : 26 lesions). No difference was found between FPD and CFSS in the diagnosis of the lateral view of the lesions. However in enface view examination, FPD, compared with CFSS showed a greater ability to visualize the findings of subtle nodules, depressions and tumor margin clearly. Furthermore, FPD images showed a greater ability to diagnose mucosal cancer with superficial invasion (m₁ and m₂) (p＝0.03). From these results, it was concluded that, compared with traditional radiography, FPD is superior in detecting superficially invasive esophageal cancers.