Effects of Short-Term Moisturizer Application in Different Ethnic Skin Types: Noninvasive Assessment with Optical Coherence Tomography and Reflectance Confocal Microscopy

Abstract

Background/Aims: Ethnic skin types are known to differ in their morphological and physiological features. Thus, treatment responses may vary among different races. We aimed to assess skin morphology of different ethnicities and to compare the effect of short-term moisturizer application using optical coherence tomography (OCT) and reflectance confocal microscopy (RCM). Methods: Thirty healthy female subjects of European, Asian and Black ethnicity at 30–45 years of age were included in the study. OCT and RCM imaging was performed on the cheek to compare morphology. Following the 2-week application of a moisturizer cream (Sebamed® lotion) on one forearm, imaging was performed on both forearms to assess and compare treatment responses. Results: Epidermal thickness and morphology of pores varied between the three ethnic groups, with Black subjects displaying the thickest epidermis and largest skin pores. On the treated forearm, OCT measurements revealed a significantly thicker epidermis in all groups as compared to the untreated forearm. Width of skin folds on the treated forearm was measured by RCM to be significantly lower in all ethnic groups as compared to the untreated forearm. Conclusion: Different ethnic skin types showed variations in skin morphology and treatment response to short-term moisturizer application. OCT and RCM were useful methods for noninvasive, real-time, repeated assessment of ethnic skin.

In vivo examination of healthy human skin after short‐time treatment with moisturizers using confocal Raman spectroscopy and optical coherence tomography: Preliminary observations

“…Concerning skin morphology and blood vessels analysis, we reported an increase in BF at a depth of 0.3 mm between timelines T1 and T2 in the treated arm, probably due to mechanical stimulation causing vasodilatation. Accordingly, we saw a significant decrease in the skin roughness parameters (Ra and Rz) between baseline and T1 only in the moisturized arm, indicating a smoothening of the skin surface, in line with our previous study 33 . We found no statistically significant changes in the AC; in particular, we could not observe the expected decrease of AC observed in other studies after treatment with glycerol, probably because our measurements were not taken immediately after moisturizing 39 …”

“…Reflectance confocal microscopy (RCM) provides high‐resolution horizontal imaging of epidermis and papillary dermis enabling assessment of cellular details. In our previous study assessing the same moisturizing lotion in different ethnic skin types, we observed a reduced width of skin folds following 2 weeks application of the same moisturizing lotion on the treated arms as compared to the control arms using RCM 33 . On the other hand, Manfredini et al.…”

Influence of Ethnicities and Skin Color Variations in Different Populations: A Review

“…The epidermis of intensely pigmented samples is low dyskeratotic and vacuolated compared to samples of the epidermis of more minor pigmented. Although there is no discernible skin thickness difference between white and black skin, black skin possesses more corneocytes in the stratum corneum than white skin, implying a more dense and compacted layer [75, 76]. Black skin has a higher mean electrical resistance than white skin, which is most likely due to this compaction [77].…”

Differences in the Sub-Metatarsal Fat Pad Atrophy Symptoms between Patients with Metatarsal Head Resection and Those without Metatarsal Head Resection: A Cross-Sectional Study

“…Alterations in skin hydration are common among patients with diabetes [34]. Less hydration has been associated with thinner skin and measurements of skin, derma, and fat can be affected by different hydration statuses [35]. We did not evaluate skin hydration in this study; however, it could modify the results.…”