Effectiveness of Vascularized Lymph Node Transfer for Extremity Lymphedema Using Volumetric and Circumferential Differences

Abstract

Background:Circumferential difference of lymphedematous limbs at designated anatomic distances has been the primary mode for measuring lymphedematous extremities. Computed tomography (CT) imaging produces accurate, consistent, hygienic volume measurements and a direct limb representation. This study compares these 2 main modalities and assesses their correlation.Methods:CT and circumferential difference measurements, costs, and correlation of patient limbs that received vascularized lymph node transfer were compared.Results:Mean circumferential difference by tape measurement pre- and postoperatively was 31.4% ± 19.1% and 17.4% ± 8.8% for upper limbs and 43.2% ± 16.1% and 22.4% ± 12% for the lower limbs, respectively. Mean CT volumetric difference pre- and postoperatively were 36.1 ± 4.1% and 27.2 ± 2.8% for the upper limb and 46.2 ± 3.2% and 33.2 ± 2.1% for the lower limbs, respectively. CT volume measurements significantly correlated with their respective circumferential difference with Pearson correlation coefficient of r = +0.7, which was statistically significant (P = 0.03), indicating a strong positive correlation between circumferential difference and actual limb volume changes as determined by CT imaging. Circumferential differences are more cost effective than CT volume assessments in the domains of measurement frequency (P = 0.03), fee (P < 0.01), time (P = 0.03), total cost per year (P < 0.01), and cost/minute (P = 0.03).Conclusions:Standardized circumferential differences that are currently used are comparable to unbiased CT volumetric measurements and can be used as a reliable, reproducible, minimally invasive, low cost, and accurate method of measuring the lymphedematous limbs.

Staging and clinical correlations of lymphoscintigraphy for unilateral gynecological cancer–related lymphedema

“…Although the limb circumferential measurements are a useful tool for monitoring the progress of the lymphedematous limb, improving communication between medical personnel and patients, there have been several critiques against this method for not providing an accurate assessment of volume. However, in a recent study circumferential and CT measurements have been demonstrated being highly complementary …”

“…A standardized CT volumetric protocol was used by our Radiology Department from 2002 and performed for all patients with extremity lymphedema preoperatively and 1‐year postoperatively . CT imaging was performed to provide a more consistent and standardized method to measure the volume of the lower extremity lymphedema from the ankle joint to the level of iliac bone.…”

“…Hence, all the CT images were collected and stored in a Digital Imaging and Communications in Medicine format archive for the radiologist review. Similarly, CT volumetric differences were calculated as the volume of the normal control lower limb was subtracted from the volume of the lymphedematous lower limb and divided by the volume of the normal limb …”

Breast Cancer-Related Lymphedema: Recent Updates on Diagnosis, Severity and Available Treatments

“…However, several critiques have been moved against this tool for not allowing a precise assessment of limb volume. Conversely, a study showed that circumferential and CT measurements are highly complementary in the assessment of volume in the lymphedematous limb [ 29 ].…”

“…CT can detect lymphedema features including skin thickening, honeycombing or presence of fat lobules. It provides a standardized and reproducible method to measure the limb volume providing a 3-D representation of the lymphedematous limb [ 29 ].…”