Late Breaking Abstract: Detection and Quantitation of Venous Leg Edema with a Novel Ruler and Ultrasound

Introduction, Objectives, and/or Purpose: Lower extremity edema is characteristic of C3 and higher chronic venous disease resulting from impaired venous return. However, objective quantitation and reporting of leg edema has not been well-defined. We developed a clinical and ultrasound methodology for the detection and quantification of leg edema and prospectively evaluated its usefulness.

Methods: A 3D-printed plastic Edema RulerTM was developed and used to measure depth of pitting edema (Figure). Twenty-two consecutive patients (44 legs) were prospectively evaluated for ankle edema using the ruler and ultrasound imaging. Clinical data including age, gender, BMI, along with CEAP and revised Venous Clinical Severity Score (rVCSS), were recorded. Patients were separately evaluated by two individuals, in a blinded fashion, for ankle edema on the tibia 5 cm above the medial malleolus. An index finger was firmly pressed for 20 seconds and pitting depth then measured with the ruler. Ultrasound (US) images were acquired at the same site and later evaluated independently by two observers in a blinded fashion using a modified Suehiro grading scale. Interobserver reliability was calculated with a two-way random intraclass correlation coefficient.

Results: The 22 patients included 5 males and 17 females with a mean age of 56 ± 15 years and a BMI of 27.3 ± 4.7. CEAP C1-3 stages comprised 64% of the patients while the remainder were C4. Their mean total rVCSS was 5.02 ± 2.79. Interobserver reliability for the Edema RulerTM was 0.969 (p < 0.001) and for the modified ultrasound Suehiro grading system 0.877 (p <0.001). The correlation between the pitting depth and the modified ultrasound Suehiro grade was 0.459 (p=0.002). There was also a significant correlation between these two methods and clinical parameters (Table). However, measured pitting depth with the ruler had a stronger correlation with all clinical parameters. Of note, 70% of legs (7/10) clinically classified with no edema were found to have some edema on ultrasound analysis.

Conclusion(s): The Edema RulerTM provides an easy and objective measurement of edema pitting depth with excellent interobserver reliability. Ultrasound analysis provides a qualitative evaluation with early detection of subcutaneous edema not evident on clinical examination.