中面部牵引成骨术后眶周结构三维位置变化的评估

目的 观察中面部牵引成骨技术对眼眶周围软、硬组织结构的三维空间位置变化的影响.方法 回顾性分析2003年9月至2006年6月接受Le Fort III型截骨+中面部牵引成骨术的8例Crouzon综合征患者CT数据,平均年龄11.9岁,实施影像三维重建后,采用眶耳平面(术前)作为测量的基准平面,分别选择眶上点、眶下点、眶内缘点、眶外缘点、眼球前点、眼球后点,以及上、下、内、外四直肌与眼球的附着点作为评估标志,以双侧耳门上点连线作为颅底宽度基准,记录各个主要标志点至耳门上点连线的矢状距(y轴向)、垂直距(z轴向)以及眼球前点、眼球后点的水平间距(x轴向)变化,行配对t检验,并与健康对照组比较.结果 牵引成骨术前后眼球前点的y轴向及z轴向位置并没有显著性变化,但x轴向间距变化为-3.40 mm;眶下点移动在y轴向平均12.24 mm,z轴向平均4.25 mm;眶内缘点移动在y轴向平均10.11 mm,z轴向平均2.80 mm;眶外缘点移动在y轴向平均9.86 mm,z轴向平均2.31mm;下直肌支点移动,y轴向平均3.63mm,z轴向平均2.98mm.其余各标记点未见有临床意义的位移变化.结论 以Le Fort III型截骨为主的面中部牵引成骨技术,可以使Crouzon综合征患者的术后眼眶内、外、下侧壁均出现明显的前、下方移位,而患者的眼球没有显著性的矢状向位置变化,仅呈现轻度的内移、下降和前上方旋转.

3-dimensional position changes of periorbital structures after midface distraction osteogenesis

Objective To evaluate the 3-D position changes of periorbital structures after midface distraction osteogenesis in patients with Crouzon syndrome.Methods The CT data of 8 cases who had accepted the midface distraction osteogenesis following Le Fort Ⅲ osteotomy were retrospectively analyzed.The patients were averagely 11.9 years old,and the CT was performed before and one year after operation.After 3-D image recoastruction,a right-hand coordinate system based on the preoperational Frankfurt Plane was then established.The pre-and pest-operative positions of the superior orbit point(SOr),inferior orbit point(IOr),median orbit point(MOr),lateral orbit point(LOr),anterior ocularis point(AO),ocularis eyeball point(PO)and the four insertio ocularis rectus were documented and compared.The positions of these marked points in normal controls were also documented and compared with those in patients.Results After midface distraction osteogenesis,the position of AO was not changed significantly on the y-axis and z-axis,but the distance between two AO points on x-axis was reduced by 3.40 mm;IOr moved averagely 12.24 mm on y-axis and 4.25 mm on z-axis,MOt moved averagelv 10.11 mm on y-axis and 2.80 mm on z-axis,LOr moved averagely 9.86 mm on y-axis and 2.31 mm on z-axis The Inferior Rectus attachment moved averagely 3.63 mm on y-axis and 2.98 mm on z-axis.No other significant cbenge was observed on other marked points.Conclusions Midface distraction osteogenesis following Le Fort III osteotemy Can significantly move the medial,lateral and inferior peri-orbital bone structure anteriorly and inferiorly.The eyeballs have no markedly sagital position changes after distraction except slight medial,downwards movements and anterior-upwards rotations.