Department of Surgical Sciences, Section of Vascular Surgery, Uppsala University Hospital, Uppsala; Department of Surgery, Mälarsjukhuset, Eskilstuna, Sweden.
Br J Surg. 2014 May;101(6):633-6. doi: 10.1002/bjs.9463.
Three ultrasound methods of measuring the diameter of the abdominal aorta exist: the outer-to-outer (OTO) method, where callipers are placed on the outer layer of the aortic wall; the inner-to-inner (ITI) method, where callipers are placed on the inner layer of the aortic wall; and the leading edge-to-leading edge (LELE) method, where callipers are placed on the outer layer of the anterior wall and the inner layer of the posterior wall. The aim was to determine the variability of the three methods, differences between them, and the consequences on prevalence estimates.
Some 127 consecutive patients with a small abdominal aortic aneurysm (AAA) were included. The maximal anteroposterior diameter was measured using the OTO, ITI and LELE methods by two vascular sonographers who were blinded to each other's measurements. The variability was described as the standard deviation.
The variability was 2.7 (95 per cent limits of agreements ± 5.4) mm for the OTO, 2.3 (± 4.6) mm for the ITI and 2.0 (± 4.0) mm for the LELE method. The corresponding coefficients of variability were 6.4, 6.1 and 5.0 per cent. The difference was 4.1 mm between ITI and OTO (P < 0.001), 2.0 mm between ITI and LELE (P < 0.001), and 2.1 mm between LELE and OTO (P < 0.001).
LELE measurement was the most reproducible method of measuring the abdominal aorta. All methods showed a high degree of variability.
有三种测量腹主动脉直径的超声方法：外-外（OTO）法，卡尺放置在主动脉壁的外层；内-内（ITI）法，卡尺放置在主动脉壁的内层；前缘-前缘（LELE）法，卡尺放置在前壁的外层和后壁的内层。目的是确定三种方法的可变性、它们之间的差异以及对患病率估计的影响。
纳入了 127 例连续的小腹主动脉瘤（AAA）患者。通过两位血管超声医师采用 OTO、ITI 和 LELE 方法对最大前后径进行测量，两位医师彼此之间的测量结果相互盲法。可变性用标准差表示。
OTO 法的可变性为 2.7（95%可信区间为±5.4）mm，ITI 法为 2.3（±4.6）mm，LELE 法为 2.0（±4.0）mm。相应的变异性系数分别为 6.4%、6.1%和 5.0%。ITI 与 OTO 之间的差值为 4.1mm（P<0.001），ITI 与 LELE 之间的差值为 2.0mm（P<0.001），LELE 与 OTO 之间的差值为 2.1mm（P<0.001）。
LELE 测量是测量腹主动脉最具可重复性的方法。所有方法均显示出高度的可变性。
