Leg Edema Quantification for Heart Failure Patients via 3D Imaging

Abstract

Heart failure is a common cardiac disease in elderly patients. After discharge, approximately 50% of all patients are readmitted to a hospital within six months. Recent studies show that home monitoring of heart failure patients can reduce the number of readmissions. Still, a large number of false positive alarms as well as underdiagnoses in other cases require more accurate alarm generation algorithms. New low-cost sensors for leg edema detection could be the missing link to help home monitoring to its breakthrough. We evaluated a 3D camera-based measurement setup in order to geometrically detect and quantify leg edemas. 3D images of legs were taken and geometric parameters were extracted semi-automatically from the images. Intra-subject variability for five healthy subjects was evaluated. Thereafter, correlation of 3D parameters with body weight and leg circumference was assessed during a clinical study at the Medical University of Graz. Strong correlation was found in between both reference values and instep height, while correlation in between curvature of the lower leg and references was very low. We conclude that 3D imaging might be a useful and cost-effective extension of home monitoring for heart failure patients, though further (prospective) studies are needed.

Prioritizing symptom management in the treatment of chronic heart failure

“…Peripheral swelling is included in most symptom questionnaires because weight gain can be masked by cachexia 63 . Newer optical scanners utilize non‐contact depth sensing methods to create advanced 3D images for determining changes in leg shape, size, and consistency 81 . Hence, novel approaches to oedema monitoring are needed to build a model of disease progression and facilitate patient‐directed diuretic dose adjustment, balancing the risk of renal impairment.Pharmacological treatment for peripheral oedema is focused around diuretics and mineralocorticoid receptor antagonists with further medications to prevent formation through disease management.…”

“…63 Newer optical scanners utilize non-contact depth sensing methods to create advanced 3D images for determining changes in leg shape, size, and consistency. 81 Hence, novel approaches to oedema monitoring are needed to build a model of disease progression and facilitate patient-directed diuretic dose adjustment, balancing the risk of renal impairment.Pharmacological treatment for peripheral oedema is focused around diuretics and • Additional three questions focus on physical activity limited by dyspnoea or the fear of dyspnoea on the average day. This gives an overall score of 0-120.…”

Volumetric assessment of lower limb oedema using 3D laser scanning technique: a systematic review

“…Two systems for assessing oedema using a 3D scanner were used: platform-based standing and handheld. Two studies [11,12] used tape measure, and one [10] used WD volumetry as a "gold standard method" for assessing reliability of the 3D scanners.…”

Evaluation of the Accuracy of a Video and AI Solution to Measure Lower Leg and Foot Volume

“…This study was conducted in accordance with the Declaration of Helsinki, and based on 58 participants, all of whom gave written informed consent. Of these, 30 were healthy volunteers who took part in a clinical trial which was then underway (NCT02993601, note that this protocol was part of the clinical trial approval, West Midlands-South Birmingham Research Ethics Committee, NHS, Health Research Authority, UK, REC ref 16/WM/0522), 22 were volunteers from an office setting and 6 from a professional cardiology conference; 22 the last two groups were enrolled as part of post-market surveillance activities. There was variation in the age, gender and ethnicity of included participants, even though we did not intend to recruit a specific representation of each.…”

“…Hayn et al 22 apply 3D imaging as a method to partially automate such an estimate from a series of distance measures; however, it does not appear that this work has led to a commercially available product, providing a proof of concept but no change in clinical availability of measuring techniques. A more direct optical approach is taken by the Perometer (Perometer, Pero-System Messgeraete GmbH, Wuppertal, Germany $30,000), a device that automatically measures the circumference (or, more correctly, the circumference of the convex hull) of an object repeatedly as it is passed through a square frame containing light-emitting diodes and photodiodes.…”