# Assessment of the Degree of Erythema Reduction in Rosacea After Polychromatic Light Treatments

## TL;DR

This study shows that three polychromatic light treatments significantly reduce redness in rosacea patients, with effects lasting at least three months.

## Contribution

The study combines subjective and objective methods to evaluate the effectiveness of polychromatic light in treating rosacea erythema.

## Key findings

- Three polychromatic light treatments reduced erythema by 61.11% on the CEA scale.
- GLCM analysis showed a 17% decrease in contrast and 4–5% increase in homogeneity after treatment.
- Treatment effects lasted for at least three months with strong correlation between CEA and GLCM results.

## Abstract

Background: Rosacea is a chronic facial skin disease in which persistent erythema is a significant clinical problem, often resistant to standard therapies. Intensive pulsating light (IPL) has become a recognised and effective method of treating erythema and telangiectasia. The latest recommendations emphasise the advantage of combining subjective clinical assessments with objective imaging analyses in monitoring therapy effects. Methods: A total of 20 patients with rosacea qualified for this study. They were subjected to three polychromatic light procedures (Lumecca, Inmode; wavelength of 515–1200 nm) at 21-day intervals. The skin condition was documented photographically, and the degree of erythema was assessed on the basis of the Clinician Erythema Assessment (CEA) scale and objective analysis of the skin texture, using the parameters of contrast and homogeneity of the grey level co-occurrence matrix (GLCM). Results: A series of three polychromatic light treatments yielded a significant clinical improvement in all patients. The mean CEA value decreased by 61.11%, whereas the GLCM contrast in all the analysed facial areas dropped by about 17%, and homogeneity increased by 4–5%. The effects persisted for at least three months after the treatments. A high correlation of CEA scale results with GLCM parameters (R = 0.81–0.94 for contrast; R = −0.77 to −0.83 for homogeneity) was observed. Conclusions: Three polychromatic light treatments proved to be a very effective method of reducing erythema in rosacea, confirmed by both clinical evaluation and objective imaging analysis. The effects of therapy were durable and clear. Integration of the subjective method (CEA) with GLCM analysis can be a path for future research and clinical practice in the assessment of erythematous skin lesions.