CT多平面重组技术测量骨性鼻泪管的优势

Advantage of CT multi planar reconstruction technique for the measurement of nasolacrimal duct

目的比较CT多平面重组技术与常规CT轴位图像测量单侧先天性鼻泪管阻塞患儿骨性鼻泪管不同位置的径线。探寻两种测量方法各自的优势。方法回顾性分析18例泪道探通手术失败的单侧先天性鼻泪管阻塞患儿的CT检查。常规应用CT轴位图像测量骨性鼻泪管高度,起始段、中段及末段骨性鼻泪管的横径、垂直径;再经过CT多平面重组技术调整测量角度后测量上述径线。同时对比患侧及健侧的结果。结果 CT轴位图像测量法与MPR测量方法高度差异明显(P<0.01),两种测量法的起始段、中段及末段骨性鼻泪管垂直径相互间差异明显(P<0.01),横径测量结果显示,患侧末段有差异(P<0.01),余各测量部分差异不明显(P>0.05),并且MPR测量法可以观察到鼻泪管的弯曲走形、开口情况,两种方法都可以明确的观察到患侧较健侧各径线明显增大,差异具有统计学意义(P<0.01)。结论与常规CT轴位图像测量方法相比较,CT多平面重组技术对骨性鼻泪管形态、走形更为全面,测量结果更可信,但对诊断准确性没有影响。

Objective Comparison of CT multi planar reconstruction technique （MPR） and the conventional axial CT technique measurements of diameters of nasolacrimal ducts with unilateral congenital nasotaerimal duct obstruction. To ex- plore the advantages of two methods for the measurements respectively. Methods 18 CT examinations of unilateral con- genital nasolacrimal duct probing through operation failed obstruction were reviewed. The height, and transverse diame- ter, vertical diameterand of nasolacrimal duct of initial segment, the middle segment and the end segment of nasolacrimal duct were measured using the routine CT axial technique and MPR. Results The initial segment, axial CT image meas- urement and MPR measurement of the middle and distal nasolacrimal ductvertical diameter are obvious differences （ P 〈0.01）, results show that measuring the transverse diameter, the affected side terminal has the difference （ P 〈0.01）, more than themeasuring part is not significantly different （ P 〉0. 05）, and MPR measurement can observe bent out of shape, nasolaerimal duct openings, two kinds of methods can beclearly observ in the ipsilateral than the contralateral, the diameter increased significantly, the difference is statistically significant （ P 〈0.01）. Conclusion Compared with the con- ventional axial CT image measurement method, CT multiplanar reconstruction of nasolacrimal duct shape, out of shape is more comprehensive, the measurement results are more credible, but has no effect on the accuracy of diagnosis.