Wiggli U, Benz U, Müller H R
Klin Monbl Augenheilkd. 1977 Feb;170(2):290-6.
The normal suprasellar subarachnoid space (so-called "suprasellar hexagon") and its content are fairly well demonstrated by CT. Abnormal appearance (obstruction, stenosis, asymmetry) of this space is always suspect of a suprasellar space occupying lesion. Enhancing (intravenous application of iodine containing contrast medium) helps to delineate the exact tumor extension. The point of origin--important for deciding on the nature of a lesion--is often difficult to determine. The CT-pattern itself is not specific for a certain kind of tumor. We have observed a typical chiasmatic syndrome with all meningiomas of the tuberculum sellae, with 75% of the chromophobe adenomas and with 50% of the craniopharyngiomas. Absence of this syndrome was due to high position of the tumor (craniopharyngiomas) or to parasellar extension of the lesion (chromophobe adenomas). Diagnosis of recurrent tumor is difficult; it must be based on the post-operative CT-examination. Chiasmatic syndromes not due to the pressure effect of a space occupying lesion (i.e. chiasmatic syndromes of vascular, toxic or degenerative origin) can not be assessed directly by CT.
正常的鞍上蛛网膜下腔（所谓的“鞍上六边形”）及其内容物通过CT能得到较好的显示。该腔隙的异常表现（阻塞、狭窄、不对称）总是提示存在鞍上占位性病变。增强扫描（静脉注射含碘造影剂）有助于明确肿瘤的确切范围。病变的起源点（对于判断病变性质很重要）常常难以确定。CT表现本身对某种特定肿瘤并无特异性。我们观察到，所有蝶鞍结节脑膜瘤、75%的嫌色性腺瘤以及50%的颅咽管瘤都出现了典型的视交叉综合征。未出现该综合征是由于肿瘤位置较高（颅咽管瘤）或病变向鞍旁扩展（嫌色性腺瘤）。复发性肿瘤的诊断很困难，必须基于术后CT检查。并非由占位性病变压迫效应导致的视交叉综合征（即血管性、中毒性或退行性起源的视交叉综合征）不能通过CT直接评估。
