An Observational Study to Assess Objective Skin Pigmentation Variation.

Recruiting

• Conditions: Healthy Skin; Skin Diseases

• Registration Number: NCT07091604
• Lead Sponsor: Leiden University Medical Center

Brief Summary

Accurate assessment of skin pigmentation is essential in dermatology for properly diagnosing and managing a wide range of skin conditions. Traditionally, skin colour has been evaluated through visual inspection or by using classifications like the Fitzpatrick skin type. However, these methods can be subjective, culturally biased, and often are centered around lighter skin tones, which may lead to misdiagnosis or inappropriate treatment for individuals with darker skin.

With advances in technology, non-invasive imaging tools such as colorimetry and multispectral imaging now offer more precise and objective ways to measure skin pigmentation. These methods can help provide consistent and unbiased information about skin tone, benefiting both clinical care and research. Despite these technological advances, there is currently no agreed-upon standard for how to measure skin pigmentation objectively in everyday clinical practice or research settings.

This study aims to explore better, more accurate ways to measure skin pigmentation using modern, non-invasive imaging technologies. Traditional methods for assessing skin colour, like visual inspection or classifying by ethnicity, are often unreliable and biased. In this study, researchers will use tools such as colorimetry and multispectral imaging to measure skin pigmentation more objectively.

The study includes two groups of participants: healthy adults and adults with skin conditions. Researchers will measure a value called the melanin index, which reflects the amount of pigment in the skin, and compare it across different areas of the body and among people with different skin tones and conditions.

The goal is to understand how skin pigmentation varies and to see if these new technologies can help doctors more accurately diagnose and manage skin diseases for people of all skin types.

Detailed Description

Not available

Study Timeline

• Status Verified: 2025-07
• Study First Submitted: 2025-07-21
• Study First Submitted QC: 2025-07-21
• Study Start: 2025-07-22
• Study First Posted: 2025-07-29
• Last Update Submitted: 2025-07-29
• Last Update Posted: 2025-08-01
• Primary Completion: 2027-01-22
• Study Completion: 2027-01-22

Recruitment & Eligibility

• Status: RECRUITING
• Sex: All
• Target Recruitment: 600

Inclusion Criteria

• Age ≥ 18 years
• Ability to understand oral and written Dutch or English

Exclusion Criteria

For study cohort #1 (Healthy volunteers):

• Extensive tattoos covering >50% of the total body area
• Recent extensive sun exposure (e.g. sun tanning booth or stay in a tropical country) in the last 3 weeks
• Use of self-tanner products in the last 3 weeks

For study cohort #2 (Patients):

• Extensive tattoos covering >50% of the total body area
• Extensive skin lesions covering >50% of the total body area
• Recent extensive sun exposure (e.g. sun tanning booth or stay in a tropical country) in the last 3 weeks
• Use of self-tanner products in the last 3 weeks

Study & Design

• Study Type: OBSERVATIONAL
• Study Design: Not specified

Primary Outcome Measures

Name	Time	Method
Melanin index	At baseline study visit (single time point)	Melanin index as measured by skin colorimetry and multispectral imaging.

Secondary Outcome Measures

Name	Time	Method
Age	At baseline study visit (single time point)
Skin barrier function by Skin Barrier Pro	At baseline study visit (single time point)	The barrier status by trans epidermal water loss of (non-)lesional skin and healthy skin will be determined using Skin Barrier Pro
VISIA	At baseline study visit (single time point)	VISIA is a non-invasive imaging system designed for in vivo analysis of facial skin, utilizing multi-spectral imaging and digital analysis to assess various skin features, including pigmentation, porphyrins, texture, and wrinkles. The system captures standardized, high-resolution images under different lighting conditions (including cross-polarized and UV light), allowing for both surface and subsurface visualization of the skin. It provides quantitative and comparative assessments of skin health and damage, supporting both clinical evaluation and cosmetic or dermatological research.
Laser speckle contrast imaging	At baseline study visit (single time point)	Laser speckle contrast imaging (LSCI) is a non-invasive optical imaging technique used to assess microvascular blood flow in vivo by analyzing the speckle pattern produced when coherent laser light is scattered by moving red blood cells. The resulting speckle contrast is inversely related to the velocity of blood flow, enabling real-time, high-resolution visualization of perfusion over large skin areas without the need for contrast agents. LSCI is particularly suited for dynamic monitoring of vascular responses in dermatology, wound healing, and inflammatory skin conditions.
3D Multispectral imaging	At baseline study visit (single time point)	The redness, melanin and superficial morphology of (non-)lesional skin sites and healthy skin will be determined using a 3D multispectral imaging system.
Ethnicity	At baseline study visit (single time point)	Self-reported
Colorimetry	At baseline study visit (single time point)	The melanin, redness and surface characteristics of (non-)lesional and healthy skin will be assessed using a colorimetry device that quantitatively measures skin color parameters, including melanin, based on reflected light.
Patient and Observer Scar Assessment Scale	At baseline study visit (single time point)	POSAS is a validated scar assessment tool that combines both patient-reported outcomes and clinical evaluation to provide a comprehensive assessment of scar quality. It consists of two complementary parts: the Observer Scale, completed by a clinician, which evaluates vascularity, pigmentation, thickness, relief, pliability, and surface area; and the Patient Scale, completed by the individual, which captures subjective symptoms such as pain, itching, and overall opinion of the scar. POSAS enables standardized, semi-quantitative scoring of scars, facilitating both clinical monitoring and research on scar treatment outcomes.
Scarletred® Vision	At baseline study visit (single time point)	Scarletred® Vision is a digital, non-invasive skin imaging and analysis platform that enables objective and standardized quantification of skin conditions over time using smartphone-based photography combined with a calibrated color patch and proprietary software. The system captures high-resolution images under controlled lighting conditions and applies automated analysis algorithms to quantify parameters such as erythema, pigmentation, and lesion area. By providing reproducible, color-calibrated data, Scarletred® Vision supports longitudinal skin monitoring in clinical trials and dermatological research, including evaluation of treatment effects in inflammatory and pigmentary disorders.
Fitzpatrick skin type	At baseline study visit (single time point)	Self-questionnaire and assessed by dermatologist
Line-Field Confocal Optical Coherence Tomography (LC-OCT)	At baseline study visit (single time point)	LC-OCT is a non-invasive optical imaging technique based on a combination of the optical principles of optical coherence tomography and reflectance confocal microscopy with line-field illumination, which can generate cell-resolved images of the skin, in vivo, in vertical section, horizontal section and in three dimensions.

Trial Locations

Locations (1)

Leiden University Medical Center; 🇳🇱 Leiden, Netherlands