鞍膈的解剖特点及其临床意义

目的　研究鞍膈的解剖特点，探讨其临床意义。 方法 应用成人15例尸头标本，在显微镜下进行解剖观察和测量。 结果 视交叉偏向蝶鞍左侧20%（3例），居于中线上66.7%（10例），偏向右侧13.3%（2例）。鞍隔孔完全被视交叉覆盖73.4%（11例），未被完全覆盖26.6%（4例）。鞍隔孔相对于视交叉的位置偏向左侧26.7%（4例），居于中线上66.7%（10例），偏向右侧6.6%（1例）。从上面观，鞍膈呈下凹型80%（12例），平坦型13.3%（2例），上凸型6.7%（1例）。鞍隔孔测量前后径为2.20 ~ 12.10 mm，左右径为3.10 ~ 13.40 mm；依据鞍隔孔的大小将鞍膈分为3种类型：紧密型，占13.3%（2例）；常见型，占73.4%（11例）；扩大型，占13.3%（2例）。垂体柄靠近鞍背前缘占53.3%（8例），居中占40%（6例），6.7%（1例）位于鞍结节后缘。 结论 鞍隔孔大小的变异可影响垂体瘤的生长方式，熟悉鞍膈及其周围解剖结构对鞍区手术具有重要意义。

Anatomic features of diaphragma sellae and its clinic implications

Objective　To evaluate the anatomic characteristics of diaphragma sellae and its surrounding structures and discuss its clinical implications. 　Method　Fifteen heads of adult cadavers were observed and measured under the operative microscopy.　Result 　The midpoint of the optic chiasm (OC) was located on the midline in 66.7% (10 cases) and at the left and right sides of the sella turcica in 20%(3 cases) and 13.3%(2 cases), respectively. The foramen of diaphragma sellae (FDS) was completely covered by OC in 73.4%(11 cases), and was partially covered in 26.6%(4 cases). The position of FDS relative to OC was situated in the midline in 66.7 %(10 cases), in the left side in 26.7%(4 cases) and in the right side in 6.6% (1 case). Diaphragm sellae appeared concave in 80% (12 cases), convex in 13.3%(2 cases) and flat in 6.7%(1 case) when viewed from above. The average of anteroposterior diameter of FDS was 6.59 mm (range, 2.20 ~ 12.10 mm ) and the average transverse diameter was 7.32mm (range, 3.10 ~ 13.40 mm). we classified the diaphragm sellae into three types according to the FDS diameters variations: constricted type in 13.3%(2 cases); normal type in 73.4% (11 cases); and enlarged type in 13.3%(2 cases). Pituitary stalk was sited in front of dorsum sellae in 53.3% (8 cases), in the middle part in 40% (6 cases) and in the back of tuberculum sellae in 6.7% (1 case).　Conclusion The variation in the diameter of FDS could exert influence on the growth pattern of pituitary adenomas and the detailed anatomic knowledge of diaphragma sellae and its ambient structures is helpful in improving the quality of operation in the sellar region.