Reliability and Clinical Feasibility of Three Assessment Methods for Head and Neck Lymphedema in Head and Neck Cancer Patients

<b>Background/Objectives</b>: Head and neck lymphedema (HNL) is a common complication after head and neck cancer (HNC) treatment. Reliable and feasible assessment methods are essential for monitoring and management. This study aimed to evaluate the reliability and clinical feasibility of three methods for assessing external HNL in HNC patients: local tissue water (%) using the MoistureMeterD Compact (MMDC), neck circumference using a tape measure, and dermal thickness using B-mode ultrasound. <b>Methods</b>: Thirty-three HNC patients with potential HNL were included. Measurements were performed on the same day, twice by the same rater and once by a different rater. Intraclass correlation coefficients (ICC^2,1), (relative) standard error of measurement ((%)SEM), smallest real difference (SRD), systematic differences across measurement occasions, and Bland-Altman plots with 95% limits of agreement were analyzed. Time efficiency and clinical limitations were assessed. As an exploratory analysis, Spearman correlations among methods were examined. <b>Results</b>: All methods demonstrated moderate to very strong reliability (ICCs^2,1 0.781-0.994), except dermal thickness (ICCs^2,1 0.136-0.354). Differences between raters and within one rater were not clinically meaningful. Neck circumference showed the highest reliability (ICCs^2,1 0.958-0.994) and was the fastest to perform with the fewest limitations. The methods showed weak correlations with each other. <b>Conclusions</b>: Neck circumference was the most reliable and time-efficient method assessing HNL in clinical practice but is limited to the neck region. For the head, local tissue water assessment seems the most reliable and feasible. The methods assess different aspects of HNL. Further research should confirm how these methods can complement each another.