Weitzel William F, Hamilton James, Wang Xianglong, Bull Joseph L, Vollmer Alan, Bowman April, Rubin Jonathan, Kruger Grant H, Gao Jing, Heung Michael, Rao Panduranga
Department of Veterans Affairs Medical Center, University of Michigan, Ann Arbor, Mich. USA.
Blood Purif. 2015;39(1-3):37-44. doi: 10.1159/000368973. Epub 2015 Jan 20.
BACKGROUND/AIMS: Recently, ultrasound signals termed 'lung water comets' associated with pulmonary edema have been correlated with adverse clinical events in dialysis patients. These comets fluctuate substantially during the ultrasound exam highlighting the need for objective quantitative measurement methods.
We developed an image-processing algorithm for the detection and quantification of lung comets. Quantification measures included comet number (comet count) and the fraction of the ultrasound beams with comet findings (comet fraction). We used this algorithm in a pilot study in 20 stable dialysis outpatients to identify associations between ultrasound comets and clinical parameters including blood pressure (BP), percent blood volume reduction on dialysis (%BV), ejection fraction (EF), and ultrafiltration on dialysis (UF).
Positive findings included associations with lung comet measurements with pre-dialysis Diastolic BP (r = 0.534, p = 0.015), subject age (r = -0.446, p = 0.049), and a combination of EF and end dialysis %BV reduction (r = -0.585, p = 0.028). Comet fraction and comet count were closely correlated due to the inherent relationship between these two metrics (r = 0.973, p < 0.001). Negative findings included ultrasound comets that did not change from beginning to end of dialysis (p = 0.756), and were not significantly correlated with single dialysis treatment UF (p = 0.522), subject body weight (p = 0.208), or BMI (p = 0.358).
Ultrasound signal processing methods may help quantify lung ultrasound comets. Additional findings include algorithmic lung comet measurement that did not change significantly during single dialysis sessions in these stable outpatients, but were associated with cardiovascular and fluid status parameters.
背景/目的：最近，与肺水肿相关的被称为“肺水彗星”的超声信号已与透析患者的不良临床事件相关联。这些彗星在超声检查期间波动很大，这突出表明需要客观的定量测量方法。
我们开发了一种用于检测和定量肺彗星的图像处理算法。定量测量包括彗星数量（彗星计数）和有彗星发现的超声束的比例（彗星比例）。我们在一项针对20名稳定透析门诊患者的初步研究中使用了该算法，以确定超声彗星与包括血压（BP）、透析时血容量减少百分比（%BV）、射血分数（EF）和透析时超滤（UF）在内的临床参数之间的关联。
阳性发现包括肺彗星测量与透析前舒张压（r = 0.534，p = 0.015）、受试者年龄（r = -0.446，p = 0.049）以及EF和透析结束时%BV减少的组合（r = -0.585，p = 0.028）之间的关联。由于这两个指标之间的内在关系，彗星比例和彗星计数密切相关（r = 0.973，p < 0.001）。阴性发现包括超声彗星在透析开始到结束时没有变化（p = 0.756），并且与单次透析治疗的UF（p = 0.522）、受试者体重（p = 0.208）或BMI（p = 0.358）没有显著相关性。
超声信号处理方法可能有助于定量肺超声彗星。其他发现包括在这些稳定门诊患者的单次透析过程中，算法肺彗星测量没有显著变化，但与心血管和液体状态参数相关。
