Melanin Index in Those With Fitzpatrick Skin Phototypes I-VI

Northwestern University

Status: Completed

Conditions: Erythema

Treatments: Procedure: Induced Erythema

Study type: Interventional

Funder types: Other

Identifiers

NCT01124513

JR-STU27549

Details and patient eligibility

About

The "gold standard" method of assessing skin pigmentation is spectrophotometry; however, even as early as 1961 the potential for confounding by dilatation of blood vessels was recognized. (Monash 1961) Manual compression was used to express the blood from the field being measured. The red reflectance captured by reflectance spectrophotometer introduced an uncontrollable variable when measuring the tanning /pigmentation response of skin tone/color. Room temperature induced increased or decreased blood flow through the skin, which altered the findings by spectrophotometer. Other potentially confounding variables that changed blood flow were: recent exercise, and the flushing/blushing for emotional reasons. Since these conditions were difficult to reliably control on the sun exposed extremities, spectrophotometry was not a practical method to assess change in melanin over time as an outcome measure for efficacy of sun protection.

Digital imaging with videodermatoscopy utilizing a portable device that is supported by a laptop computer, provides a high resolution digital image for analysis. (EasyScan) As described by Yamamoto et al (2008), applying the Image J freeware to quantify the pigmentation in the digital image holds promise as a practical objective method to reliably assess skin tones based on the melanin content in a non invasive manner. With standardization, the software and hardware may quantify the constitutive pigment in the sun protected skin as the melanin index.

Enrollment: 270 patients

Sex: All

Ages: 18 to 89 years old

Volunteers: Accepts Healthy Volunteers

Inclusion criteria

• at least 18 years old
• fluent in English
• able to complete the study procedures including answering questionnairs
• willing to apply ice to left upper inner arm
• willing to have digital photos, dermatoscopic photos and spectrophometry readings taken of left upper inner arm

Exclusion criteria

• have a history of vitiligo or currently has vitiligo
• use self-tanning products or tan accelerators ont he left upper inner arm int he 4 weeks prior to enrollment
• history of cold urticaria or conenctive tissue disease such as scleroderma

Trial design

Primary purpose: Screening

Allocation: Non-Randomized

Interventional model: Single Group Assignment

Masking: None (Open label)

---

270 participants in 3 patient groups

Digital Camera

Active Comparator group

Description:

Digital camera images will be taken of a a 2cm\^2 area of sun protected skin.

Treatment:

Procedure: Induced Erythema

Spectrophotometer

Active Comparator group

Description:

The probe of the protable reflectance spectrophotometer is lightly applied to the sufance of the skin and a reading is taken.

Treatment:

Procedure: Induced Erythema

Videodermoscopy

Active Comparator group

Description:

The instrument is put in contact with sun protected skin and an image is taken of a 2 cm\^2 area.

Treatment:

Procedure: Induced Erythema