Mechanobiology and force transduction in scars developed in darker skin types

Presentation, Management, and Outcomes of Pathologic Scars Within a Pediatric Otolaryngology Practice

OBJECTIVES

This study aims to review the spectrum of scarring that may present to an urban, pediatric otolaryngology practice and determine if associations exist between race, scar location, treatment modality, and outcomes following interventions for scarring.

METHODS

Retrospective cohort study among 115 pediatric patients with 138 unique keloids or hypertrophic scars (HTS), and 141 children presenting for tonsillectomy at Tufts Medical Center. Age at presentation and sex assigned at birth were collected for both populations. For those presenting for pathologic scars, income quintile, self-identified race/ethnicity, anatomical location, treatment number and type, and clinical outcome were also analyzed. Multivariate analyses calculated adjusted odds ratios (aORs) and 95% confidence intervals to assess associations between scar subsite, intervention type, and persistence after treatment.

RESULTS

Compared to individuals presenting for tonsillectomy, a disproportionate percentage of patients presenting for scarring identified as Black (26.6% vs. 13.5%) or Asian (17.4% vs. 7.1%, p = 0.016) or were male (61.7% vs. 49.7%, p = 0.053). Individuals identifying as Black or Asian were more likely to present with ear lobe and neck scars, respectively (50.0% vs. 45.5%, p = <0.001). Ear scars were significantly more likely to receive excision at initial treatment (aOR = 5.86 [1.43-23.96]) compared to other subsites, and were more likely to require >1 treatment (aOR = 5.91 [1.53-22.75]).

CONCLUSION

Among pediatric patients presenting with keloids or HTS, children who identified as Black or Asian were more likely to present with ear and neck scars, respectively. Ear scars were frequently treated with excision and appear more likely to require adjuvant treatments and multiple interventions.

LEVEL OF EVIDENCE

3 Laryngoscope, 134:3127-3135, 2024.

Hypertrophic Scar

Hypertrophic scars frequently develop post-burn, and are characterized by their pruritic, painful, raised, erythematous, dyschromic, and contractile qualities. This article aims to synthesize knowledge on the clinical and molecular development, evolution, management, and measurement of hypertrophic burn scar for both patient and clinician knowledge.

Skin Biophysical Characteristics in Patients with Keratoconus: A Controlled Study

Background. Keratoconus is a relatively common corneal disease causing significant visual disability. Individuals with connective tissue disorders that affect the skin such as Marfan's syndrome and Ehlers-Danlos syndrome or patients with atopic dermatitis show an increased prevalence of keratoconus. It seems that there are some concurrent alterations of skin and cornea in patients with keratoconus. Objective. We plan to compare skin biophysical characteristics in patients with keratoconus and healthy controls. Methods. Forty patients with keratoconus (18 females and 22 males) with mean (SD) age of 33.32 (9.55) years (range 19-56) and 40 healthy controls were recruited to this study. Skin biophysical characteristics including cutaneous resonance running time (CRRT), stratum corneum hydration, and melanin values were measured in patients and controls. Results. The median CRRT, stratum corneum hydration, and melanin measurements were significantly lower in patients with keratoconus in comparison with healthy controls. Conclusion. There are some alterations of skin biophysical properties in patients with keratoconus. Therefore, the assessment of these skin parameters could provide us some clues to the possible common biophysical variations of cornea and skin tissue in diseases such as keratoconus.

Currently known risk factors for hypertrophic skin scarring: A review

OBJECTIVE

The study aims to provide an overview of risk factors for hypertrophic scarring.

BACKGROUND

Hypertrophic skin scarring remains a major concern in medicine and causes considerable morbidity. Despite extensive research on this topic, the precise mechanism of excessive scarring is still unknown. In addition, the current literature lacks an overview of the possible risk factors in the development of hypertrophic scars.

METHODS

PubMed searches were performed on risk factors for hypertrophic scar (HTS) formation.

RESULTS

Eleven studies suggesting nine factors associated with HTS formation were found. Studies concerning chemotherapy, age, stretch, infection, and smoking have a moderate to high strength of evidence, but some other factors have not been studied in a convincing manner or are still disputed.

CONCLUSIONS

Risk factors for HTS formation are young age, bacterial colonization, and skin subjected to stretch. Chemotherapy, statins, and smoking seem to play a protective role in HTS formation.

Immunohistochemical aspects of the fibrogenic pathway in nephrogenic systemic fibrosis

Nephrogenic systemic fibrosis (NSF) is a rare gadolinium-dependent disorder of the skin and viscera. The aim of this study was to revisit some immunopathologic clues of NSF, including the characterization of glycosaminoglycans, cell tensegrity, and cell proliferation in the dermis. Immunohistochemistry was done using antibodies directed to vimentin, CD34, Factor XIIIa, calprotectin, α-smooth muscle actin, Ulex europaeus agglutinin-1 (UEA-1), and MIB1/Ki67 and to glycosaminoglycans, including CD44 var3, versican, and perlecan. The vimentin+ cell density was markedly increased. The vast majority of them corresponded to CD34+ or Factor XIIIa+ dermal dendrocytes (DD) showing distinct cell tensegrity. CD34+DD were slender, elongated, and usually scattered in the dermis but focally clustered in nodular collections. By contrast, Factor XIIIa+ was plump with squat dendrites showing no evidence for being under mechanical stress. Cells in the vicinity of the microvasculature were rounded and exhibited calprotectin immunoreactivity typical for monocyte/macrophages. The microvasculature highlighted by UEA-1 and α-smooth muscle actin looked unremarkable. The cell proliferation highlighted by the MIB/Ki67 immunoreactivity was unusually high (>20%) in the interstitial stromal cells. Stromal cells enriched in versican were plump, abundant, and seemed interconnected each other by a dense network of dendrites. By contrast, the immunolabeling for perlecan and CD44 var 3 was unremarkable. In conclusion, the cell population involved in NSF seemed phenotypically heterogeneous, and its growth fraction was clearly boosted in the skin. The intracellular load in versican was prominent. The aspect of cell tensegrity did not suggest the influence of mechanical stress putting stromal cells under tension in the dermis.

Cutaneous resonance running time varies with age, body site and gender in a normal Chinese population

BACKGROUND/OBJECTIVES

One phenomenon of skin aging is loss of cutaneous elasticity. Measurement of cutaneous resonance running time (CRRT) is a method to assess skin elasticity. Yet, information regarding the directional changes of CRRT associated with age, body sites and gender is not yet available. In the present study, we assessed whether changes in CRRT vary with age, body sites and gender in a normal Chinese population.

METHODS

A Reviscometer was used to measure CRRTs in various directions on the left dorsal hand, the forehead and the left canthus of 806 normal Chinese volunteers, aged 2.5-94 years.

RESULTS

With aging, CRRTs decreased in all directions on the hand, the forehead and the canthus. A more dramatic reduction in CRRTs on the forehead and the canthus was observed in both the 2-8 and the 3-9 o'clock directions. CRRTs in males aged 11-20 years were longer than those in females in some directions on all three body sites. Females aged between 21 years and 40 years showed longer CRRTs than males in some directions of the hand. There were no gender differences in subjects aged 0-10 (except on the canthus) and those over 80 years old.

CONCLUSION

CRRTs vary with age, body sites and gender.

A reliable, non-invasive measurement tool for anisotropy in normal skin and scar tissue

BACKGROUND

Anisotropy of the skin varies depending on different locations and pathological conditions. Currently, no reliable non-invasive measurement tool is available for tissue anisotropy. The Reviscometer is an anisotropy measurement tool that measures the resonance running time (RRT) of a shock wave. This study was initiated to establish the reliability of the Reviscometer on normal skin and scars, and to provide basic information on tissue alignment in normal skin and scars.

METHODS

Fifty volunteers and 50 patients underwent measurements on normal skin and scars, respectively. All measurements were performed by the same two observers. Measurements on normal skin were performed on the forearm, upper arm, and abdomen.

RESULTS

The results showed that the intraclass correlation coefficient of the inter-observer reliability was > or =0.79 on normal skin and > or =0.86 on scars. In normal skin, the highest mean RRT was found on the abdomen (156.4+/-48.8), followed by the upper arm (123.2+/-33.6) and the forearm (112.5+/-24.3). A significantly lower mean RRT was found in scars (52.3+/-21.9) compared with normal skin (91.6+/-37.7).

CONCLUSION

Reviscometer measurements were reliable for normal skin and scars. In addition, clear differences between scars and normal skin but also within different locations on normal skin were identified. The Reviscometer can be considered for the evaluation of the efficacy of different treatments.

High resolution skin colorimetry, strain mapping and mechanobiology

SYNOPSIS

Skin colours are notoriously different between individuals. They are governed by ethnicities and phototypes, and further influenced by a variety of factors including photoexposures and sustained mechanical stress. Indeed, mechanobiology is a feature affecting the epidermal melanization. High-resolution epiluminescence colorimetry helps in deciphering the effects of forces generated by Langer's lines or relaxed skin tension lines on the melanocyte activity. The same procedure shows a prominent laddering pattern of melanization in striae distensae contrasting with the regular honeycomb pattern in the surrounding skin.

Skin diseases in patients with beta-thalassemia major

BACKGROUND

Beta-thalassemia major affects multiple organs and is associated with considerable morbidity and mortality. The goal of this analysis was to document the frequency of skin diseases among patients with beta-thalassemia major.

METHODS

A sample of 78 patients with beta-thalassemia major was recruited and interviewed at the thalassemia clinic between April and June 2008. A dermatologist completed a skin examination of each patient and recorded any skin disease present. The patients' laboratory results and treatment modalities were recorded from the charts.

RESULTS

Sixty-five (83.3%) of the 78 patients examined had a diagnosed skin disease: pruritus (37.2%), xerosis (34.6%), scars (24.4%), ephelides (23.1%), skin irritation/erythema caused by deferoxamine pump (12.8%), idiopathic guttate hypomelanosis (6.4%), pityriasis alba (6.4%), tinea infections (5.1%), verruca vulgaris (5.1%), urticaria (3.8%), hyperhidrosis, contact dermatitis, and acne (2.6%), necrobiosis lipoidica (1.3%), melasma (1.3%), and others (14.1%). Pruritus and xerosis increased in frequency with age. The mean serum ferritin level was higher in patients with xerosis than in those without (5607.7 +/- 2997.5 ng/mL and 4285.2 +/- 4732.4 ng/mL, respectively) (P1/4 0.005). Moreover, xerosis was observed significantly more frequently inpatients using deferoxamine and deferiprone than in those using deferasirox (P1/4 0.047, P1/4 0.027, and P1/4 0.273, respectively).

CONCLUSION

Skin diseases, especially pruritus and xerosis, are observed highly frequently inpatients with beta-thalassemia major. Treatment is needed for these patients who already have other significant morbidities.

Decreased cutaneous resonance running time in cured leprosy subjects

BACKGROUND/OBJECTIVES

Leprosy prominently involves both the skin and peripheral neural tissues and some symptoms persist after microbial cure. Because alterations in the dermis also occur in leprosy, we assessed here whether there were changes in cutaneous resonance running time (CRRT), a parameter that is influenced by collagen properties, in cured leprosy subjects.

METHODS

A reviscometer was used to measure the CRRT at various directions on the dorsal hand and the flexural forearms of 76 cured leprosy subjects aged 50-85 years and 68 age-matched normal subjects.

RESULTS

In comparison to normal subjects, CRRTs on the hands and the forearms were significantly reduced in all directions in cured leprosy, except at the 1-7, 2-8 and 3-9 o'clock directions on the forearms. CRRTs were reduced significantly at both the 4-10 and 5-11 o'clock directions on the forearm in lepromatous (73.33 +/- 4.19 at 4-10 o'clock and 67.44 +/- 2.71 at 5-11 o'clock direction) and borderline lepromatous types (77.58 +/- 5.84 at 4-10 o'clock and 79.85 +/- 6.81 at 5-11 o'clock direction) as compared with normal (143.10 +/- 7.75 at 4-10 o'clock and 125.18 +/- 8.14 at 5-11 o'clock direction). On the hand, CRRTs at all directions, except that at 4-10 o'clock direction, were also significantly reduced in lepromatous and borderline lepromatous types in comparison with normal. Significant differences in CRRT at some directions were found among the various subtypes of leprosy.

CONCLUSION

CRRTs were abnormal in the cured leprosy subjects as a whole, but varied with leprosy subtypes, which suggested that the extent of reduction of CRRTs correlates with the severity of immune alteration. These results suggest that CRRT measurements could be a useful approach to quantify the extent of some residual abnormalities in cured leprosy and perhaps could also be used to evaluate the efficacy of treatment.

Forensic sexual assault examination and genital injury: is skin color a source of health disparity?

PURPOSE

The study objectives were to (1) estimate the frequency, prevalence, type, and location of anogenital injury in black and white women after consensual sex and (2) investigate the role of skin color in the detection of injury during the forensic sexual assault examination.

METHODS

A cross-sectional descriptive design was used with 120 healthy volunteers who underwent a well-controlled forensic examination after consensual sexual intercourse.

RESULTS

Fifty-five percent of the sample had at least 1 anogenital injury after consensual intercourse; percentages significantly differed between white (68%) and black (43%) participants (P = .02). Race/ethnicity was a significant predictor of injury prevalence and frequency in the external genitalia but not in the internal genitalia or anus. However, skin color variables--lightness/darkness-, redness/greenness-, and yellowness/blueness-confounded the original relationship between race/ethnicity and injury occurrence and frequency in the external genitalia, and 1 skin color variable--redness/greenness--was significantly associated with injury occurrence and frequency in the internal genitalia.

CONCLUSIONS

Although differences exist in anogenital injury frequency and prevalence between black and white women, such differences can be more fully explained by variations in skin color rather than race/ethnicity. Clinical recommendations and criminal justice implications are discussed.

Randomised, placebo-controlled, double-blind, split-face study on the clinical efficacy of Tricutan on skin firmness

Tricutan is a combination product of herbal extracts traditionally used for treatment of skin conditions, together with dimethylaminoethanol. The effectiveness of Tricutan in improving skin firmness and elasticity in photoaged facial skin was examined in a randomised, placebo-controlled, double-blind, split-face study in 28 women, 34-67 years old. Treatment with Tricutan and placebo was given for 4 weeks. Skin firmness and elasticity was evaluated using the speed of propagation of ultrasound shear waves in the skin as end point (Reviscometer RVM 600). The study was completed by 25 women. The Tricutan treatment resulted in a significantly reduced propagation speed indicating increased firmness. There was no immediate effect by Tricutan application on propagation speed. At self evaluation the women evaluated the treatment effect of Tricutan to be significantly better than the treatment effect of placebo. The clinical evaluation also showed Tricutan to give a significantly better treatment result than placebo. Tolerance to Tricutan was generally good. However, three women did not complete the study because of mild irritative contact dermatitis. The results show that Tricutan can increase skin firmness both objectively and subjectively. Further studies are warranted, especially to investigate if Tricutan can delay the need for surgical face-lift procedures.