Ward L C, Dylke E S, Kilbreath S L
Breast Cancer Research Group of the Faculty of Health Sciences, University of Sydney, Sydney, Australia.
Lymphat Res Biol. 2012 Jun;10(2):81-6. doi: 10.1089/lrb.2012.0005.
Assessment of lymphedema is frequently based upon measuring the increase in volume of the affected region compared to that of a comparable unaffected region. This requires methods that can measure the volume of body regions that are not only accurate and sensitive but also suitable for use in clinical practice. To date, bioimpedance spectroscopy has been used to measure volume increase due to lymphedema in whole arms but excluding the hand. We report here an impedance-based method for the measurement of hand volume.
Impedance measurement electrodes were located on the dorsum of the hand, with the sense electrodes at the level of ulnar styloid and metacarpal-phalangeal joint of the third finger and current drive electrodes on the forearm and at the nail bed of the third finger. The impedances of the hands of 50 participants were measured and hand volumes computed. These were compared with the hand volumes measured by perometry. The region of the hand defined by the impedance measurements was determined, both in vivo and using a hand phantom.
The region of the hand measured by the impedance technique was limited to the palmar volume (i.e., excluding the thumb). Palmar volumes computed from impedance measurements were significantly correlated (r=0.88) with those measured by perometry but were, on average, 8% larger. The impedance technique was sufficiently sensitive to detect the change in hand volume elicited by decrease in vascular volume due to blood draining from the hand on elevation.
An impedance technique was developed that has the potential to measure the change in hand volume when affected by lymphedema. Bioimpedance spectroscopy has the advantage over currently used perometric or water displacement techniques in that it can measure specifically the change in extracellular fluid, including lymph, rather than simply total hand volume.
淋巴水肿的评估通常基于测量患区与未受影响的可比区域相比的体积增加。这需要能够测量身体区域体积的方法，这些方法不仅准确、灵敏，而且适用于临床实践。迄今为止，生物电阻抗光谱法已用于测量整个手臂（不包括手部）因淋巴水肿导致的体积增加。我们在此报告一种基于阻抗的手部体积测量方法。
阻抗测量电极位于手背，传感电极位于尺骨茎突和第三指掌指关节水平，电流驱动电极位于前臂和第三指指甲床。测量了50名参与者的手部阻抗并计算了手部体积。将这些结果与通过体积描记法测量的手部体积进行比较。通过体内和使用手部模型确定了由阻抗测量定义的手部区域。
通过阻抗技术测量的手部区域仅限于手掌体积（即不包括拇指）。根据阻抗测量计算出的手掌体积与通过体积描记法测量的体积显著相关（r = 0.88），但平均大8%。阻抗技术足够灵敏，能够检测由于手部抬高时血液流出导致血管体积减少所引起的手部体积变化。
开发了一种阻抗技术，有可能测量受淋巴水肿影响时手部体积的变化。生物电阻抗光谱法优于目前使用的体积描记法或水置换法，因为它可以专门测量细胞外液（包括淋巴液）的变化，而不仅仅是手部总体积。
