锥型束CT在上颌Le Fort Ⅰ型截骨术中的应用

目的 探讨提高Le Fort Ⅰ型截骨术的安全性和准确性的方法.方法 对84例上颌正颌手术患者术前行锥型束CT(conebeam computed tomography,CBCT)扫描,提取不同的影像资料,测量定位上颌Le Fort Ⅰ型截骨区域重要解剖结构位置.结果 84例中,术前检查发现上颌窦严重发育不全3例,其各骨壁距离测量值远小于正常值;上颌第3磨牙高位阻生11例;上颌窦分隔8例,鼻中隔偏曲4例;上颌窦囊肿3例.该成像技术对正颌手术患者上颌骨翼腭管位置关系,上颌骨各骨壁的厚度,上颌窦分隔,上颌窦内潜伏病变,上颌高位阻生牙的定位,翼上颌联合情况,以及鼻中隔偏曲情况均有良好的显示,为上颌正颌手术方案设计提供了放射学的颌骨评估基础,可指导Le Fort Ⅰ型截骨的定位设计.结论 CBCT可为上颌Le Fort Ⅰ截骨提供更精准的结构解剖影像,从而提高手术的准确性与安全性.

Abstract：

Objective To improve the accuracy and safety of the Le Fort Ⅰ osteotomy. Methods Eighty-four patients underwent CBCT scan before maxillary orthognathic surgery. The anatomic structures of maxilla were marked and measured. Results In 84 cases, there were 3 cases with severe hypoplasia of maxillary sinus, 11 cases with impacted third molar, 8 cases with separation in maxillary sinus, 4 cases with the deviation of nasal septum, and 3 cases with cysts in maxillary sinus. Form CBCT images, the position of the pterygopalatine canal, the thickness of maxillary wall, hidden lesion of maxillary sinus, the location of Impacted molar, the deviation of nasal septum, and other anatomic structure could be accurately localized. CBCT could provide sufficient and valuable information in diagnosis and design for Le Fort Ⅰ osteotomy. Conclusions CBCT imaging technology could provide precise anatomic images for Le Fort Ⅰ osteotomy. It improves the accuracy and safety of the Le Fort Ⅰ osteotomy.