Localised Objective Characterisation Assessment of Lymphoedema (LOCAL): Using High-Frequency Ultrasound,...

Area of Science:

• Biomedical Engineering
• Medical Imaging
• Clinical Diagnostics

Background:

• Lymphoedema tissue is defined by excess fluid and extracellular matrix (ECM) changes, including fibrosis and fat deposition.
• Current lymphoedema assessment primarily focuses on fluid volume and lymphatic function, neglecting tissue composition.
• There is limited understanding of how clinical interventions impact lymphoedema tissue composition.

Purpose of the Study:

• To introduce a novel classification system, the Localised Objective Characterisation Assessment of Lymphoedema (LOCAL), for lymphoedema tissue.
• To combine diagnostic and clinically meaningful objective thresholds for assessing lymphoedema pathophysiology.
• To evaluate the utility of the LOCAL classification in characterizing tissue layer changes.

Main Methods:

• The LOCAL classification was developed using objective assessment thresholds.
• Data from fifteen women with unilateral breast cancer-related lymphoedema were analyzed.
• High-frequency ultrasound (HFUS), bio-electrical impedance spectroscopy (BIS), and volume measurements were used at three sites per arm.

Main Results:

• Significant uneven volume distribution was observed between proximal and distal arm segments (p = 0.023).
• Multiple tissue compositional categories were identified across different sites on the same limb (p < 0.001).
• The LOCAL method effectively categorized diverse lymphoedema tissue layer changes, surpassing whole-limb measures.

Conclusions:

• The LOCAL classification provides a novel, objective method for assessing lymphoedema tissue composition.
• This classification reveals detailed, localized tissue changes not evident from global measurements.
• The LOCAL method enhances understanding of lymphoedema pathophysiology and potential treatment effects.