正常脳下垂体，脳下垂体腫瘍およびトルコ鞍周辺疾患に対する脳定位手術の応用

TRANSSPHENOIDAL STEREOTAXIC APPROACH TO THE NORMAL PITUITARY, PITUITARY TUMOR, AND PARASELLAR DISEASE

はじめに

　脳下垂体（下垂体）外科は遠くSir Victor Horsley^1）にもどる。彼は1889年視神経交叉を圧迫している腫瘍に対し前頭葉を挙上し，初めて下垂体に到達した。これより数年後Schloffer^2）は経鼻的経蝶形骨的下垂体切除術に初めて成功した。他方Marie^3）は1886年に先端巨大症を記載し，これが下垂体生理解明の第一歩となつた。その後Schlofferの広範手術からHirsch^4），Cush—ing^5）の経粘膜下到達法に至る種々の下垂体到達路の考案がなされた。また一方現在までに，経蝶形骨法から開頭術へ，また一変して経蝶形骨法へと下垂体到達方法の大まかな変遷がみられたが，これは不完全切除および脳脊髄液漏出（髄液漏）・髄膜炎さらには死亡といつた術後合併症に対する考慮，また経蝶形骨法においてはその手術野の問題によるものであつた。

　最近下垂体茎部切載術^6）7），Cryosurgery^8）の応用，陽子・α粒子の下垂体照射方法^9）10），Microsurgeryの応用^11），が出現するに至り，ここ20年下垂体手術は新時代に入つたといつてよかろう。

A detailed method of transsphenoidal stereotaxic radiofrequency thermal hypophysectomy was des-cribed. Operation was carried out with careful ana-tomical consideration of the pituitary gland, the sella turcica, and the parasellar structures, so that ablation of pituitary function was complete with minimal side effects such as diabetes insipidus, or serious postoperative complications such as cerebro-spinal fluid rhinorrhea, meningitis or death. To avoid rhinorrhea, a soft silicon-silver plug was devel-oped to occlude the site of penetration of the sella floor. This tactic did not induce local infection in well over 100 consecutive patients so treated, des-pite our earlier anxiety. Rhinorrhea occurred in two out of 42 patients with diabetic retinopathy treated at Jeflerson Medical College in Philadelphia, and in two of 32 cases of metastatic breat cancer operated at Beth Israel Hospital in 1968. These were treated by stereotaxic transphenoidal muscle packing.

This method was used to ablate the function of not only the normal pituitary gland but also active pituitary adenomas. Also employment of this tactic was most useful for the biopsy of tumor of the pituitary gland and parasellar tumor for tissue diagnosis and postoperational external radiation. It was the conclusion of observations in patients with pituitary adenomas that combined stereotaxic treat-ment and irradiation was a safe and effective ap-proach, even in patients with suprasellar extension.

A case of metastatic breast cancer, and of retro-orbital metastatic tumor were presented.