Fujisawa I, Asato R, Okumura R, Nakano Y, Shibata T, Hamanaka D, Hashimoto T, Konishi J
Department of Radiology, Kyoto University School of Medicine, Japan.
Cancer. 1991 Sep 1;68(5):1009-14. doi: 10.1002/1097-0142(19910901)68:5<1009::aid-cncr2820680517>3.0.co;2-r.
The authors reviewed magnetic resonance (MR) images in seven cases of germinoma in the hypothalamoneurohypophyseal axis (HNA). The intrasellar portions were clearly identified in six germinomas. Two small germinomas of these six were located only in the neurohypophysis. The major parts of the four large germinomas were located below the optic chiasm, and the large intrasellar portions were demonstrated. The remaining one small germinoma was localized from the pituitary stalk to the third ventricular floor. These findings strongly suggest that the primary site of germinomas in the HNA is the neurohypophysis. In the four large germinomas, the tumor shape was similar to that of pituitary adenoma. The authors believe that age (limited to first three decades), symptoms (diabetes insipidus), MR findings (absence of normal hyperintense signal of the posterior pituitary on T1-weighted (T1WI) images, and homogeneous hypointensity to the pons on T1WI images/isointensity on T2-weighted images are important in differential diagnosis.
作者回顾了7例发生于下丘脑-神经垂体轴（HNA）的生殖细胞瘤的磁共振（MR）图像。6例生殖细胞瘤的鞍内部分均可清晰显示。这6例中的2例小生殖细胞瘤仅位于神经垂体。4例大生殖细胞瘤的主要部分位于视交叉下方，并显示出较大的鞍内部分。其余1例小生殖细胞瘤位于垂体柄至第三脑室底部。这些发现强烈提示HNA生殖细胞瘤的原发部位是神经垂体。在4例大生殖细胞瘤中，肿瘤形态与垂体腺瘤相似。作者认为年龄（限于头三十年）、症状（尿崩症）、MR表现（T1加权（T1WI）图像上垂体后叶正常高信号缺失，T1WI图像上相对于脑桥呈均匀低信号/T2加权图像上等信号）在鉴别诊断中很重要。
