Jean Lette1. 1. Department of Nuclear Medicine, Maisonneuve Hospital, Montréal, Québec, Canada. jlette@lette.com
Abstract
PURPOSE: We designed an arm volumeter specifically for home use based on the water displacement method. The objective of this study was to determine its accuracy and precision, and compare it with a standard volumeter used in lymphedema clinics worldwide. PATIENTS AND METHODS: Using a standard model hospital volumeter and our own device, we took three consecutive measurements of 11 specially cast cylinders, which had known volumes ranging from 10 mL to 4 L, and measurements of both arms of 15 volunteers. RESULTS: Measurements with both volumeters were highly accurate (R2 = 0.9999) when compared with the known volumes of the cast cylinders, and were strongly correlated (R2 = 0.9974) when each arm volume was compared between volumeters. Measurements with our volumeter were more precise both with the cylinders (average standard deviation [SD], 3.2 v 8 mL; P = .0553) and with the arms (average SD, 11.1 v 19 mL; P = .0034). Whereas the standard volumeter is expensive, fragile (acrylic), and prone to leaks, our volumeter is inexpensive, virtually indestructible, leak proof, and suitable for home use. CONCLUSION: Arm volumes can be measured quickly and accurately at home using a simple, inexpensive, and robust device based on water displacement. Readily accessible arm volumetry at home may have widespread influence on the management of lymphedema after breast cancer.
PURPOSE: We designed an arm volumeter specifically for home use based on the water displacement method. The objective of this study was to determine its accuracy and precision, and compare it with a standard volumeter used in lymphedema clinics worldwide. PATIENTS AND METHODS: Using a standard model hospital volumeter and our own device, we took three consecutive measurements of 11 specially cast cylinders, which had known volumes ranging from 10 mL to 4 L, and measurements of both arms of 15 volunteers. RESULTS: Measurements with both volumeters were highly accurate (R2 = 0.9999) when compared with the known volumes of the cast cylinders, and were strongly correlated (R2 = 0.9974) when each arm volume was compared between volumeters. Measurements with our volumeter were more precise both with the cylinders (average standard deviation [SD], 3.2 v 8 mL; P = .0553) and with the arms (average SD, 11.1 v 19 mL; P = .0034). Whereas the standard volumeter is expensive, fragile (acrylic), and prone to leaks, our volumeter is inexpensive, virtually indestructible, leak proof, and suitable for home use. CONCLUSION: Arm volumes can be measured quickly and accurately at home using a simple, inexpensive, and robust device based on water displacement. Readily accessible arm volumetry at home may have widespread influence on the management of lymphedema after breast cancer.