Diagnostic Performance of Muscle Echo Intensity and Fractal Dimension for the Detection of Frailty Phenotype

Abstract

To determine the relationship between muscle echo intensity (EI) and fractal dimension (FD), and the diagnostic performance of both ultrasound parameters for the identification of frailty phenotype. A retrospective interpretation of ultrasound scans from a previous cohort (November 2014–February 2015) was performed. The sample included healthy participants <60 years old, and participants ≥60 divided into robust, pre-frail, and frail groups according to Fried frailty criteria. A region of interest of the rectus femoris from the ultrasound scan was segmented, and histogram function was applied to obtain EI. For fractal analysis, images were processed using two-dimensional box-counting techniques to calculate FD. Statistical analyses were performed with diagnostic performance tests. A total of 102 participants (mean age 63 ± 16, 57 men) were evaluated. Muscle fractal dimension correlated with EI ( r = .38, p < .01) and showed different pattern in the scatter plots when participants were grouped by non-frail (control + robust) and frail (pre-frail + frail). The diagnostic accuracy for EI to categorize frailty was of 0.69 (95%CI: 0.59–0.78, p = .001), with high intra-rater (ICC: 0.98, 95%CI: 0.98–0.99); p < .001) and inter-rater (ICC: 0.89, 95%CI: 0.75–0.95; p < .001) reliability and low measurement error for both parameters (EI: −0.18, LOA95%: −10.8 to 10.5; FD: 0.00, LOA95%: −0.09 to 0.10) in arbitrary units. The ROC curve combining both parameters was not better than EI alone ( p = .18). Muscle FD correlated with EI and showed different patterns according to frailty phenotype, with EI outperforming FD as a possible diagnostic tool for frailty.

The Usefulness of Radiomics Methodology for Developing Descriptive and Prognostic Image-Based Phenotyping in the Aging Population: Results From a Small Feasibility Study

“…Muscle quality, expressed as echo-intensity, has been researched with great interest and ultrasound can identify structural changes in the muscle caused by muscle degeneration, specifically the increase of adipose and intramuscular connective tissue that results in an increased echo-intensity of the assessed muscle ( Pillen et al, 2009 ; Wilhelm et al, 2014 ; Akima et al, 2016 ). Studies that have used fractal dimension, a texture radiomic feature, to characterize muscle changes with ultrasound, have found similar evidence of increased connective tissue and fiber disorganization in the muscle as echo-intensity and heterogeneity increases ( Cury et al, 2018 ; Mirón Mombiela et al, 2021 ).…”

“…The data set consisted of 7 ultrasound images from 101 patients after excluding those with incomplete image data. The measured site was the midpoint between the superior border of the patella and the anterior superior iliac spine, with the transducer positioned perpendicular to the longitudinal axis of the femoral quadriceps ( Mirón Mombiela et al, 2021 ). Three cross-sectional images contained annotations from the previous study and one longitudinal image were excluded from the analysis.…”

Correlation of ultrasound measurement of limb muscle thickness and echo intensity with frailty assessment in elderly patients undergoing malignancies surgery

“…Pearson's correlation analysis showed it was significantly correlated with muscle thickness and echo intensity of the lower limbs. With aging, muscle function decreases in older people due to a decline in muscle composition and infiltration of adipose tissue, which may account for the increased of muscle echo intensity [ 14 ]. In contrast, the muscle thickness and echo intensity of the upper limb had no statistical significance.…”

“…It leads to muscle mass decrease. Muscle thickness and mass are closely related to muscle strength and function and are a reliable indicator for early detection of sarcopenia [ 14 , 28 ]. Muscle thickness and mass also play a crucial role in the physiological function of older adults [ 29 ].…”

DataSheet1.pdf

“…The data set consisted of 7 ultrasound images from 101 patients after excluding those with incomplete image data. The measured site was the midpoint between the superior border of the patella and the anterior superior iliac spine, with the transducer positioned perpendicular to the longitudinal axis of the femoral quadriceps (Mirón Mombiela et al, 2021). Three crosssectional images contained annotations from the previous study and one longitudinal image were excluded from the analysis.…”