CT评估隧道式多孔聚乙烯植入材料修复眼眶骨折眶容积的改变

目的 探讨CT图像和计算机眼眶容积测算程序评估和预测隧道式多孔聚乙烯植入材料(MCI)修复大范围眼眶骨折后眼眶容积改变的临床意义.方法 收集单眼大范围眼眶骨折行MCI植入术且手术前、后检查资料完整患者16例,利用计算机Volume程序根据CT图像回顾性定量分析手术前、后眼眶容积的改变,使用Hertel突眼计测量手术前、后的眼球突出度.患者受伤到接受手术的平均时间为(17.4±10.0)d,平均随访时间为9个月.结果 手术后CT图像显示全部患者眼眶内前中段MCI位置良好.手术前伤眼眼眶容积[(28.16±4.32)cm3]与对侧健眼[(23.94±3.47)cm3]比较,差异有统计学意义(t=3.044,P＜0.01);手术后双眼眼眶容积比较,差异无统计学意义(t=0.069,P＞0.05).手术前、后眼眶容积的改变量与手术前眼球内陷程度相关(r=0.715,P＜0.01),缓解眼球内陷2 mm需手术整复眼眶容积2.86 cm3.结论 利用计算机客观测量眼眶容积可对创伤后眼眶骨折的严重程度和可能出现的眼球内陷进行预测.在大范围眼眶骨折导致眼眶容积改变时,在适应证范围内利用MCI行手术治疗是重建眼眶的有效方法,CT图像和计算机眼眶容积测算程序可为手术提供重要数据.

Effect of porous polyethylene channel implants on volume reconstruction of large orbital wall fractures evaluated by computed tomography measurement

OBJECTIVE: To assess the clinical effectiveness of porous polyethylene medpor channel implants (MCI) to restore orbital volume in repairing orbital wall fractures, evaluated by computed tomography (CT) and volume measurement program. METHODS: Sixteen patients with unilateral large orbital fractures were included in this study. Computed tomography (CT) scans were used to obtain computer-based orbital volume measurement to assess the change in orbital volume pre- and post-operatively. Pre- and post-operative enophthalmos were measured using a Hertel exophthalmometer. The average time interval between injury and surgery was (17.4+/-10.0) days, and the mean follow-up period was 9 months. RESULTS: Postoperative CT scan showed that most of the MCI to be well positioned. The orbital volume of the injured orbit was significantly increased [mean: (28.16+/-4.32) cm3] as compared with unaffected orbit preoperatively (t=3.044, P<0.01). There was no statistical difference in orbital volume between the injured and normal orbits after orbital reconstruction (t=0.069, P>0.05). The orbital volume change after reconstructive surgery was significantly positively correlated with the decrease of enophthalmos (r=0.715, P<0.01). In order to resolve 2 mm enophthalmos, more than 2.86 cm3 orbital volume augmentation is recommended. CONCLUSIONS: Orbital volume measurement by CT scan is useful in the post-traumatic evaluation of severity of orbital fractures, and it can help predict the degree of late enophthalmos. Orbital reconstruction with the MCI, when indicated, is recommended.