逆流性食道炎のX線像と鑑別診断

Radiologic Findings and Differential Diagnosis of Reflux Esophagitis

　逆流性食道炎のX線像で最も目につきやすい所見としては，運動性の異常，内腔の狭小化，裂孔ヘルニアの存在，逆流所見などが挙げられよう．しかし，これらは非特異的な間接所見であって，必ずしも逆流性食道炎の存在を証明するものではない．逆流性食道炎のX線所見としては，軽症な場合，機能的な壁伸展性と辺縁の極く軽微な不整像，皺襲の太さの変化，粘膜面の粗糙さ，散在するバリウム斑，更に下部食道の円筒状ないしは楔状の内腔の狭小化像などとして描き出される．更にびらんを形成し，潰瘍が出現すればX線像では他の消化管におけると同様に淡いバリウム斑やニッシェとして写し出すことができる．

　X線学的に鑑別診断しなければならないものは少なからずあるが，最も重要なものは食道癌であろう．われわれの施設に紹介された逆流性食道炎の症例の半数以上のものが食道癌の診断が付されていることからも理解できよう．そこで，まず逆流性食道炎とこれと鑑別すべき疾患を，特に食道癌を中心に供覧することにする．

　In discolored type of reflux esophagitis, radiologic findings include mild marginal irregularity, poor distensibility, luminal narrowing, and rough mucosal surface. In errosive and ulcerative type, shallow erosion could not always be detected by radiologic examination, and it is important to visualize the E-G junction precisely beatuse the ulcer mostly occurs along the E-G junction and may induce annular stricture.

　On the other hand, traction erosion along the longitudinal axis may show cylindrical narrowing from the E-G junction to upper portion of the esophagus as well as irregular margine with vague, longitudinal barium flecks. More deeper ulcer is relatively easy to be detected by radiologic examination and multiple lesions are common feature in that case. In protruded hypertrophic type, diffuse fine nodularity is the prominent radiologic feature.

　Most important differential diagnosis of the reflux esophagitis is superficial flat type and superficial depressed type of esophageal cancer. In reflux esophagitis with large ulcer, ulcer type of advanced cancer should be differentiated. As exceptional case, there is infiltrative type esophageal cancer mimicking to the reflux esophagitis. In cases which have mucosal irregularity or rigidity, malignant lesions should be considered. Furthermore its location or presence of hiatus hernia could be useful to differentiate reflux esophagitis from esophageal cancer. On the other hand, esophageal cancer may associate with hiatus hernia and this possibility should be kept in mind.

　Other diseases such as scleroderma, esophagitis secondary to moniliasis and virus are also the subjects to be differentiated from reflux esophagitis.