Ploder Oliver, Klug Clemens, Voracek Martin, Burggasser Georg, Czerny Christian
Clinic for Cranio- and Maxillofacial Surgery, University of Vienna Medical School, Vienna, Austria.
J Oral Maxillofac Surg. 2002 Nov;60(11):1267-72; discussion 1273-4. doi: 10.1053/joms.2002.35722.
In this retrospective study, we evaluated isolated blowout fractures of the orbital floor by region-of-interest measurements from coronal computed tomography (CT) scans and their relationship to ophthalmologic findings.
Fracture area and volume of displaced tissue of blowout fractures in 38 patients were measured from coronal CT scans. Measurement was performed by identifying distances (for area calculation) of the fracture and identifying areas (for volume calculation) of the displaced tissue in each CT slice. The calculated data were then compared with the amount of enophthalmos, presence of diplopia, and limitation of ocular motility.
Orbital floor area (mean +/- SD) was 5.72 +/- 1.07 cm(2); fracture area, 2.63 +/- 1.20 cm(2); and the volume of displaced tissue, 1.15 +/- 0.91 mL. The average proportion of the fracture within the orbital floor was 45.3 +/- 17.6%. Fracture area and volume of displaced tissue were significantly positively correlated with enophthalmos and diplopia and not correlated with the limitation of ocular motility. For enophthalmos of 2 mm or greater, mean fracture area (mean +/- SD) was 4.08 +/- 1.09 cm(2) and volume of displaced tissue was 1.89 +/- 1.19 mL; for less than 2-mm enophthalmos, 1.98 +/- 0.83 cm(2) and 0.83 +/- 0.58 mL, respectively. Enophthalmos of 2 mm can be expected with 3.38 cm(2) of fracture area and 1.62 mL of displaced tissue.
Region-of-interest measurement from coronal CT scan has an application in the assessment of patients with pure blowout fractures of the orbital floor and adds useful information in posttraumatic evaluation of orbital fractures.
在这项回顾性研究中，我们通过冠状位计算机断层扫描（CT）扫描的感兴趣区域测量评估了单纯眶底爆裂骨折及其与眼科检查结果的关系。
从38例患者的冠状位CT扫描中测量爆裂骨折的骨折面积和移位组织体积。测量方法是确定骨折的距离（用于面积计算）以及每个CT切片中移位组织的面积（用于体积计算）。然后将计算得到的数据与眼球内陷程度、复视情况以及眼球运动受限情况进行比较。
眶底面积（平均值±标准差）为5.72±1.07 cm²；骨折面积为2.63±1.20 cm²；移位组织体积为1.15±0.91 mL。骨折面积占眶底面积的平均比例为45.3±17.6%。骨折面积和移位组织体积与眼球内陷和复视呈显著正相关，与眼球运动受限无关。对于眼球内陷2 mm或更严重的患者，平均骨折面积（平均值±标准差）为4.08±1.09 cm²，移位组织体积为1.89±1.19 mL；对于眼球内陷小于2 mm的患者，平均骨折面积分别为1.98±0.83 cm²和移位组织体积为0.83±0.58 mL。当骨折面积为3.38 cm²和移位组织体积为1.62 mL时，预计会出现2 mm的眼球内陷。
冠状位CT扫描的感兴趣区域测量可用于评估单纯眶底爆裂骨折患者，并为眼眶骨折的创伤后评估提供有用信息。
