片側性副鼻こう炎症例におけるＣＴ‐ｓｃａｎ像とゆがみ 上がくどう後壁骨肥厚像の検討とファントーム実験

Abstract

Recently CT-scan has been widely used for the observation and diagnosis of various diseases in the otorhinolaryngological field. Findings of CT-scan might be available for the dicision of the staging of maxillary cancer. Meanwhile, there are some artifacts on the image of CT-scan, especially of the nasal and paranasal sinuses, which are consisted with complicated thin bony walls. We sometimes observed apparent thickening of the posterior bone wall of the maxillary sinus in the cases of unilateral sinusitis, but it was not observed during the operation. To be proved any artifact of CT-scan, phantom studies using with hen's egg in various condition were done. It suggests that the image of the posterior bone wall was sometimes affected and was made as "thickened" by the overlapping of the high density object, i. e., mucopurulent discharge or really thickened maxillary membrane. If there is early stage of maxillary cancer, the small bone destruction might be cancelled with this artifact and misdiagnosis will be made. We should pay special attention to define the false shadow on the CT-scan in the case of unilateral sinusitis or of the maxillary cancer.