Quantitative vs. Qualitative Assessment of the Effectiveness of the Removal of Vascular Lesions Using the IPL Method—Preliminary Observations

Round 1

Reviewer 1 Report

This paper proposes a methodology for the acquisition of the skin images in a visible light in a repeatable manner. This methodology provides the feature of assessing and comparing between the condition of the skin before and after applying any sort of IPL treatments. The main aim for this is to reduce the erythema that was resulted from the Lumecca device. The methodology is based on the combination of the GLCM and the Quadtree algorithms. The work is interesting, but some questions should be answered carefully.

1.      The methodology is applied on a small number of subjects (13 only) can the authors apply there work on more number of subjects?

2.      What are the main contributions of the proposed study?

3.      What are the advantages and the limitations of the proposed work?

4.      Can the authors compare their work with the previous studies in terms of performance and efficiency?

5.      There should exist a related work section that represents the previous work or the studies that applied methods in the removal of vascular lesions.

6.      What is the main purpose of the mexametric measurements?

7.      What is the complexity of the proposed methodology?

Author Response

Aleksandra Lipka-Trawińska, M.D.                           Sosnowiec, October 24th 2022

Department of Basic Biomedical Science,

Faculty of Pharmaceutical Sciences in Sosnowiec,                                    

Medical University of Silesia in Katowice, Poland

 

Dear Reviewer,

I am very grateful for the valuable opinions and remarks. I agree with all the comments and I have referred to them as best as possible in a revised version of the manuscript. List of corrections is presented below:

The methodology is applied on a small number of subjects (13 only) can the authors apply there work on more number of subjects?

We plan to expand the group of volunteers, the presented results can be treated as preliminary observations, which proved the validity of the method. Nevertheless, the preliminary results are very promising.

The phrase “-preliminary observations” has been added to the title.

What are the main contributions of the proposed study?

The main aim of the research was to develop objective, repeatable methods of assessing the effectiveness of erythema treatments. The currently used methods are either qualitative or only semi-quantitative. The quantitative assessment of the effectiveness of the treatment will not only allow to compare different technologies with each other, but at the same time - after completing the tests - indicate which initial parameters of the patient's skin may affect the effectiveness of the treatment. This may allow the treatment parameters to be optimized in relation to individually defined (quantified) characteristics of the patient's skin.

The relevant fragment has been added to the manuscript.

What are the advantages and the limitations of the proposed work?

The main advantage of the proposed method is repeatability and objectivity. Most of the analyzes of the influence of various physical stimuli on the condition of skin affected by erythema and / or rosacea are based on subjective scales. The assessment performed by a specialist is always associated with a subjective verdict based on experience. In addition, the assessment performed by a specialist is more dependent on the type of light in which the observations are carried out (color temperature, angle of incidence, polarization, uniformity of illumination). The proposed method enables the skin to be illuminated under repeatable conditions. However, the proposed method also has its limitations. First of all, these are the limitations associated with a relatively large number of factors that may affect the obtained effect: e.g. skin pigmentation disorders. The proposed methodology of initial image processing minimized the influence of other factors on the obtained image analysis and processing coefficients, but it could not be completely eliminated.

The relevant fragment has been added to the discussion section.

Can the authors compare their work with the previous studies in terms of performance and efficiency? There should exist a related work section that represents the previous work or the studies that applied methods in the removal of vascular lesions.

The researchers have not used the same analysis methods in this indication, so far (the effectiveness of a high-energy light source in the therapy of erythema/dilated blood vessels). Hence, the results have not been compared with previous studies.

What is the main purpose of the mexametric measurements?

The Mexameter is a well-known device mainly used to assess the degree of skin pigmentation (melanin content) and the degree of skin redness (hemoglobin content). [1-3] The aim of this measurements was to show that the measurement of the degree of redness using a mexameter is not a very precise method and while the tool works well in assessing the degree of reduction of hyperpigmentation, it should not be the only tool for assessing the degree of skin redness. In this case, it should be mentioned that the mexameter allows to determine the melanin/hemoglobin content in the area of about 1mm2. This causes a huge variability of the results depending on the place where the mexameter is applied. The proposed methods of image analysis and processing, which identify the advancement of changes on any large area of the skin, do not have a similar disadvantage.

The relevant fragment has been added to the discussion section.

What is the complexity of the proposed methodology?

The method proposed in the article is based on the acquisition of images and mathematical analysis. Advanced methods of image analysis and processing have been proposed. In order for the image analyzes to be biometric (repeatable, objective), it required the development of a methodology for the acquisition of patients' images in optimal conditions (image resolution, recording format, type of skin illumination).

Author Response File: Author Response.docx

Reviewer 2 Report

The article presents a novel application of a well-known methodology such as photography to monitor and follow the evolution of a treatment with pulsed light (IPL) and which is shown to be sensitive after three sessions (not treatments) of the treatment. Although I believe that the work is promising, there is still a long way to go to be able to use this methodology. Here are some details and my big doubts about it:

-The title is too ambitious for what the article actually shows. I recommend to mention of the development of a methodology (photography) for the follow-up of treatments with pulsed light. It is better to simplify the title since the work shows preliminary results.

-In the abstract the photographic method is not specified, and it should (FOTOMEDICUS system (Elfo, Poland)) because all the work is based on that method.

-The n (13) is too small considering the age range (20-54 years) with a very different memory in the skin precisely due to age and also that patients have up to 3 different pathologies. We cannot consider each photograph as a different sample (255) and the methodology does not explain how many images are collected from each individual.

-Although it talks about the methodology of the FOTOMEDICUS system (Elfo, Poland) it does not explain the standard conditions it uses, nor if the photograph is always taken at the same time. This is extremely important when assessing the skin since it is not the same as whether or not the patient has been in the sun during the day or comes from work or exercise. This circumstance is not well explained in materials and methods.

-The results are promising but insufficient, perhaps that is the reason why there are no differences with the Mexameter® from Courage-Khazaka Electronic. It may not be the most correct skin measurement device to make a comparison. It fundamentally measures melanin in the skin and here, in order to compare, a device that measures vascularization is needed.

-In any case, I believe that the study of the images is well done, and the results are very encouraging to propose this methodology as a quantitative method of monitoring light treatment, although more data is needed to really confirm it.

-In the discussion it is repeated several times that it is new, and new is the application of a widely used and well-known methodology.

-Some references are missing in the discussion, as there are paragraphs that establish statements without any supporting reference.

 

Author Response

Aleksandra Lipka-Trawińska, M.D. Sosnowiec, October 24th 2022

Department of Basic Biomedical Science,

Faculty of Pharmaceutical Sciences in Sosnowiec,

Medical University of Silesia in Katowice, Poland

 

Dear Reviewer,

I am very grateful for the valuable opinions and remarks. I agree with all the comments and I have referred to them as best as possible in a revised version of the manuscript. List of corrections is presented below:

• The title is too ambitious for what the article actually shows. I recommend to mention of the development of a methodology (photography) for the follow-up of treatments with pulsed light. It is better to simplify the title since the work shows preliminary results.

Thank you for your valuable notice, of course it will be appropriate to change the title to preliminary observations.

“-preliminary observations” has been added to the title.

• In the abstract the photographic method is not specified, and it should (FOTOMEDICUS system (Elfo, Poland)) because all the work is based on that method.

We agree and added this information to the summary.

 

• The n (13) is too small considering the age range (20-54 years) with a very different memory in the skin precisely due to age and also that patients have up to 3 different pathologies. We cannot consider each photograph as a different sample (255) and the methodology does not explain how many images are collected from each individual.

The photographic documentation includes 5 images in cross-polarized light and 5 images in non-polarized light before the series of treatments and 5 images in cross-polarized light and 5 images in non-polarized light after the series of treatments. As a result, 260 images are analyzed. Of course, we are aware that a higher number of volunteers would increase the quality of the obtained analyzes, but it is a preliminary study and the expansion the number of volunteers along with the extension of the analysis are planned.

The relevant fragment has been added to the methodology section.

• Although it talks about the methodology of the FOTOMEDICUS system (Elfo, Poland) it does not explain the standard conditions it uses, nor if the photograph is always taken at the same time. This is extremely important when assessing the skin since it is not the same as whether or not the patient has been in the sun during the day or comes from work or exercise. This circumstance is not well explained in materials and methods.

The acquisition of images was carried out in constant temperature conditions, around 20ºC, in the morning. After reaching the test site, the patient was asked to rest in a sitting position for 20 minutes before the measurements. The photos were taken under artificial lighting, where all lighting parameters were precisely controlled, including color temperature, lamp power, light direction, light polarization.

 

The relevant fragment has been added to the methodology section.

• The results are promising but insufficient, perhaps that is the reason why there are no differences with the Mexameter® from Courage-Khazaka Electronic. It may not be the most correct skin measurement device to make a comparison. It fundamentally measures melanin in the skin and here, in order to compare, a device that measures vascularization is needed.

Mexameter® by Courage-Khazaka Electronic is widely used to assess the degree of skin pigmentation, and there are also studies in which the reduction of erythematous changes was assessed using the above-mentioned device. We agree with the opinion of the reviewer that Mexameter® should not be the only tool for assessing the degree of skin redness, newer studies suggest the use of the Colorimeter (®) device or the Antera (®) 3D device [1, 2], so in future works, we want to show that there are more precise methods which objectively measure the degree of redness.

• In any case, I believe that the study of the images is well done, and the results are very encouraging to propose this methodology as a quantitative method of monitoring light treatment, although more data is needed to really confirm it.

We plan to expand the research group, we propose to treat this results as preliminary research.

• In the discussion it is repeated several times that it is new, and new is the application of a widely used and well-known methodology.

The use of a known method of image analysis and processing in a new application the authors understand as a novelty. The text specifies what the authors understand by novelty.

• Some references are missing in the discussion, as there are paragraphs that establish statements without any supporting reference.

Unfortunately, the literature in this area - the use of quantitative methods of image analysis and processing to assess the effectiveness of high-energy light treatments is negligible. Hence, the authors referred to a limited number of publications.

Author Response File: Author Response.docx

Round 2

Reviewer 1 Report

The manuscript is suitable for publication.

Reviewer 2 Report

The manuscript has improved a lot and the answers of the authors meet the minimum for its acceptance.