Kim Jonathan W, Goldberg Robert A, Shorr Norman
Division of Orbito-facial Surgery, Jules Stein Eye Institute, UCLA School of Medicine, Los Angeles, California.
Ophthalmic Plast Reconstr Surg. 2002 Sep;18(5):355-64. doi: 10.1097/00002341-200209000-00007.
To study the anatomic and radiographic features of the inferomedial orbital strut (IOS), with particular emphasis on the region of the posterior IOS.
Cadaver dissection study of the IOS was performed on 20 orbits of 10 fresh-frozen cadaver specimens. Radiographic volumetric analysis was performed on CT scans of 20 orbits to measure the volume available for decompression in the region of the posterior IOS.
The anterior IOS provided bony support to the orbit and served as a site of attachment for globe-supporting suspensory ligaments. The midportion of the IOS demonstrated a contiguous anatomic relation to the maxillary sinus ostium. The posterior IOS consisted of two components: the intraorbital process of the palatine bone and ethmoidal air cells that extended inferior and posterior to the IOS. Radiographic volumetric analysis demonstrated that there was an average of 2.1 mL of volume available for decompression in the region of the posterior IOS (range, 1.2 to 3.3 mL).
The findings of this anatomic and radiographic study of the inferomedial orbital strut support the concept of a posterior inferomedial orbital decompression. The region of the posterior IOS appears to offer significant volume for axial globe mobilization while minimizing the risk of globe dystopia and/or impairment of the maxillary sinus drainage.
研究眶内侧下支柱（IOS）的解剖学和影像学特征，尤其着重于IOS后部区域。
对10个新鲜冷冻尸体标本的20个眼眶进行IOS的尸体解剖研究。对20个眼眶的CT扫描进行影像学容积分析，以测量IOS后部区域可用于减压的容积。
IOS前部为眼眶提供骨性支撑，并作为眼球支撑悬韧带的附着部位。IOS中部与上颌窦口呈现连续的解剖关系。IOS后部由两部分组成：腭骨眶内突和在IOS下方及后方延伸的筛窦气房。影像学容积分析表明，IOS后部区域平均有2.1 mL的容积可用于减压（范围为1.2至3.3 mL）。
这项关于眶内侧下支柱的解剖学和影像学研究结果支持眶内侧后减压的概念。IOS后部区域似乎为眼球轴向移动提供了可观的容积，同时将眼球异位和/或上颌窦引流受损的风险降至最低。
