涙道閉塞症例の涙道内CT像

Computerized tomography findings in nasolacrimal dysfunction

　涙道閉塞症，涙道狭窄症17例22側のCT像を検討した．涙嚢部は涙嚢炎の存する例では，CT値が約＋40で比較的粘稠な物質の存在を示唆し，涙嚢炎の存しない例ではCT値が約＋20〜＋30で涙液よりはわずかに高い値を示した．閉塞部と思われる部位は，特発例では涙嚢鼻涙管移行部から上部鼻涙管であり，外傷や副鼻腔手術などによるものでは中部から下部鼻涙管であり，いずれの場合にもその部の陰影は一様で，CT値は＋60〜＋80と肉芽性変化を示唆する値であった．狭窄例では，各断層面の鼻涙管内CT値は種々の値を示し内部の状態が一様でないことを示唆していた．

　これらの結果，涙道閉塞症の病態がいっそう明らかとなり，涙道手術に際し有用な情報が得られた．

We examined 17 cases (22 lesions) with stenosis or obstruction in the lacrimal drainage system with the use of computerized tomography (CT). In idio pathic cases, the site of obstruction was located either in the upper nasolacrimal duct or at the junction of the lacrimal sac and the naso-lacrimal duct. In post-traumatic cases, it was located in the lower nasolacrimal duct.

The obstructed areas appeared as homogenous in CT image with CT values ranging between +60 and +80. These findings were suggestive of granula-tion tissue. The stenosed areas appeared, on the other hand, as areas of unequal density. Lacrimal passage appeared to be maintained through the low-density portion. The CT values of the lacrimal sac was around +40 in dacryocystitis and around +20 to +30 other cases.