Skin thickness of Korean adults

Cigarette burns in forensic medicine

Skin lesions suspected to have been caused by a burning cigarette require thorough diagnostic evaluation as to the mode of infliction. Accidental cigarette burns must be differentiated from injuries due to self-infliction or maltreatment. The typical categories are presented on the basis of the literature and exemplary cases from the authors' own study material. An intentional infliction must be taken into consideration when a body region is involved which does not normally come into contact with a cigarette by chance. Full thickness burns from glowing cigarettes require an exposure time of more than 1s. One should also keep in mind the possibility of confusion with local skin infections or thermal effects by traditional medical practices (e.g. moxibustion). In unclear cases, repeated inspection of the lesion is recommended in order to facilitate its classification as to causation and age. The courses of healing in first- to third-degree cigarette burns are demonstrated by means of continuous photographic documentation. The discussion deals with different kinds of accidental and intentional cigarette burns, e.g. in drug addicts, psychiatric patients, victims of child abuse, maltreatment and torture, but also in persons feigning a criminal offence.

Double-Eyelid Operation: Orbicularis Oculi–Levator Aponeurosis Fixation Technique

Incision techniques in the past focused on fixing the pretarsal skin to either the tarsal plate or to the levator aponeurosis. High relapse rate remains one of the main concerns in double-eyelid surgery. To address these issues, the author developed a pretarsal orbicularis oculi muscle-levator aponeurosis fixation technique. This technique results in better fixation between the skin and the levator aponeurosis by recruiting a bulky, pretarsal orbicularis oculi muscle in the fixation mechanism. This technique provides for a solidly fixed, tightly stretched pretarsal skin when the eyes are open with significantly reduced chances of relapse.

Studies of the in vivo radiosensitivity of human skin fibroblasts

BACKGROUND AND PURPOSE

To examine the radiosensitivity of skin cells obtained directly from the irradiated skin of patients undergoing fractionated radiation treatment prior to surgery for treatment of soft tissue sarcoma (STS) and to determine if there was a relationship with the development of wound healing complications associated with the surgery post-radiotherapy.

METHODS

Micronucleus (MN) formation was measured in cells (primarily dermal fibroblasts) obtained from human skin at their first division after being removed from STS patients during post-radiotherapy surgery (2-9 weeks after the end of the radiotherapy). At the time of radiotherapy (planned tumor dose - 50Gy in 25 daily fractions) measurements were made of surface skin dose at predetermined marked sites. Skin from these sites was obtained at surgery and cell suspensions were prepared directly for the cytokinesis-blocked MN assay. Cultured strains of the fibroblasts were also established from skin nominally outside the edge of the radiation beam and DNA damage (MN formation) was examined following irradiation in vitro for comparison with the results from the in situ irradiations.

RESULTS

Extensive DNA damage (MN) was detectable in fibroblasts from human skin at extended periods after irradiation (2-9 weeks after the end of the 5-week fractionated radiotherapy). Analysis of skin receiving a range of doses demonstrated that the level of damage observed was dose dependent. There was no clear correlation between the level of damage observed after irradiation in situ and irradiation of cell strains in culture. Similarly, there was no correlation between the extent of MN formation following in situ irradiation and the propensity for the patient to develop wound healing complications post-surgery.

CONCLUSIONS

Despite the presence of DNA damage in dermal fibroblasts weeks after the end of the radiation treatment, there was no relationship between this damage and wound healing complications following surgery post-irradiation. These results suggest that factors other than the radiosensitivity of the skin fibroblasts likely also play a role in wound healing in deep wound sites associated with surgery for STS following radiation therapy.

Partial Necrosis of Expanding Postauricular Flaps during Auricle Reconstruction: Risk Factors and Effective Management

BACKGROUND

Tissue expansion has gradually become accepted as a useful adjunct to auricular reconstruction. Necrosis of postauricular flaps during the expansion phase may hinder auricular reconstruction. This study was designed to investigate the risk factors for partial necrosis of expanding postauricular flaps during reconstruction of the auricle and to provide effective management strategies.

METHODS

Data were gathered retrospectively for cases of partial necrosis of expanding postauricular flaps from the overall group of patients undergoing auricular reconstruction after preliminary tissue expansion at a treatment center from January of 2002 to January of 2005. Demographic data, ulcer occurrence, treatment procedure, and results were analyzed statistically.

RESULTS

The authors observed that 2.5 percent of congenital microtia cases and 13.8 percent of acquired auricular defect cases suffered from partial necrosis of expanding postauricular flaps. Necrosis in more cases occurred during static expansion and was located on the inferior part of the expanded flap. Treatment included the following: (1) auricular reconstruction with autologous costal cartilage or a porous polyethylene framework for a limited term; (2) continuing static expansion, with the postauricular flap extended and fixed in place after expander removal; and (3) removal of the expander and reinsertion of a similar expander more than 6 months after the wound had healed. Each method was applied to different types of cases. Most cases obtained a satisfactory contour and profile of the reconstructed auricle.

CONCLUSIONS

Some individual and iatrogenic factors are involved in partial necrosis of expanding postauricular flaps, which can be prevented and minimized. An optimal method can be chosen to treat every case of partial necrosis of the expanding postauricular flap.

Porcine ear skin: an in vitro model for human skin

BACKGROUND/PURPOSE

Porcine ear skin is used in studies of percutaneous penetration as a substitute for human skin. The structure of this tissue, including hair follicles, was studied qualitatively and quantitatively in comparison with human skin.

METHODS

Sections of shock-frozen biopsies, biopsies embedded in paraffin and cyanoacrylate skin surface biopsies were investigated using microscopy. The thickness of the different skin layers and the follicular characteristics were determined.

RESULTS

The thickness of the stratum corneum was 17-28 microm, whereas the viable epidermis was 60-85 microm thick. On 1 cm(2), 11-25 hairs were detected, showing a diameter of 58-97 microm and a maximal extension depth of 0.96-1.38 mm into the skin. The orifices of the porcine infundibula showed a diameter of approximately 200 microm.

CONCLUSIONS

The results obtained are similar to those of human skin, indicating the suitability of this porcine tissue as a model for human skin.

Generation and distribution of reactive oxygen species in the skin of hairless mice under UVA: studies on in vivo chemiluminescent detection and tape stripping methods

Although the formation of reactive oxygen species (ROS) in the skin induced by the ultraviolet (UV) light has been shown to lead to many cutaneous disorders, skin cancer and photoageing, the mechanism and distribution of ROS generation has not yet been definitively determined. In the present study, we examined the distribution of UVA-induced ROS in the skin of live hairless mice, using our proposed in vivo imaging chemiluminescent (CL) method to detect ROS combined with a CL probe (cypridina hilgendorfii luciferin analogue; CLA) and tape stripping (TS) technique. The CL intensities in the skin of live hairless mice were confirmed to significantly increase by UVA exposure. When TS was conducted five times in a maximum level after CL measurement following UVA exposure and subsequent CLA application, CL intensities due to UVA-induced ROS generation in the residual skin decreased to 10% of the original levels; and those in the stripped skin on each tape decreased in the stripped order such as 52%, 16%, 11%, 6% and 5%. Next, CLA was applied and then CL intensities were measured in the residual skin after advance 1, 3 and 5 tape strippings, and CL intensities due to ROS were detected primarily in the outer layer of the skin. On the basis of these results, we concluded that ROS induced by UVA exposure occurs and distributes in the outermost layer of the stratum corneum.

Thickness of Korean Upper Eyelid Skin at Different Levels

This study aims at elucidating the thickness of the Korean upper eyelid at different levels. Left eyelids of 10 (9 males and 1 female) fresh Korean cadavers were dissected. Full thickness upper eyelids were cut and trichrome stained. The thickness was measured under a microscope.The thickness of upper eyelid skin varied at different levels. The thickest part of the upper eyelid is just below the eyebrow (D) (1.127 +/- 238 microm), and the thinnest skin is near the ciliary margin (A) (320 +/- 49 microm). The upper tarsal area (C) and mid tarsal area (B) are 832 +/- 213 and 703 +/- 103 microm, respectively. "A" area was significantly thinner than mid tarsal "B" area (P = 0.000). The skin above the tarsus was thicker than the "B" area, but there was no significant difference (P = 0.081). The skin just below the eyebrow, "D," was thicker than the upper tarsal border, "C" area (P = 0.011). The epidermis accounted for 11.2% of the entire skin near the ciliary margin. However, epidermis presented less (4.2-5.5%) of the whole skin at other levels (P = 0.000). The distance between ciliary margin and the point where the skin turns suddenly thicker was 1.89 +/- 0.23 mm. The size of the tarsal plate was 8.88 +/- 0.81 mm. These data of upper eyelid skin thickness may apply to Asian double fold surgery and also to full thickness skin donation for grafting.

Racial/ethnic differences in perineal, vaginal and cervical lacerations

OBJECTIVE

To determine if variation exists between ethnicities for risk of perineal, vaginal, and cervical laceration at vaginal delivery.

STUDY DESIGN

Retrospective cohort study of nulliparous women who underwent vaginal delivery of a vertex presentation. Predictor variable was ethnicity with outcome variables cervical, vaginal, and second-, third-, or fourth-degree perineal laceration. Logistic regression analysis was conducted to control for confounders.

RESULTS

Of the 17,216 who met criteria, Filipino (OR = 1.92, 95% CI 1.64-2.25) and Chinese (OR = 1.60, 95% CI 1.33-1.92) women were at greatest risk for third- and fourth-degree laceration. Only Filipino (OR = 1.32, 95% CI 1.10-1.57) and other Asian (OR = 1.23, 95% CI 1.08-1.41) women were at slightly increased risk of vaginal laceration. No differences were seen for cervical laceration.

CONCLUSION

Different ethnicities are at widely varying risk of perineal laceration, but little difference exists for vaginal or cervical lacerations. Research into the mechanisms behind this should investigate differences in perineal anatomy.

Are there ethnic differences of facial movements between Europeans and Asians?

PURPOSE

Due to the widespread use of Free Functional Muscle Transplant (FFMT) around the world to reanimate the paralysed face, it is important to be aware of ethnic differences in facial movements.

METHODS AND MATERIAL

Participants in this study were born in Taiwan (n=24) and Austria (n=24). Analyses were conducted applying the digitised three-dimensional video-analysis system. All 48 subjects have never undergone any treatments in the face nor did they have previous histories of craniofacial anomalies.

RESULTS

In general, Europeans were observed to have larger facial movements than Asians, from 0.4 mm (e.g. 5.7%) up to 3.9 mm (e.g. 30.3%), on average 1.3 mm+/-0.82 SD (e.g. 20.6%). Particularly the eyebrow, nose and mouth regions show statistically significant larger excursions on average 1.4 mm (e.g. 19.9%), 1.3 mm (e.g. 34.6%) and 3.0 mm (e.g. 30.3%). One exception is in the eye region, where Asians have a larger excursion (1.4 mm, e.g. 15.8%) of the eyelids, due to the larger distances between the upper and lower eyelids in the rest position.

CONCLUSION

Europeans have generally larger facial movements than Asians. Particularly the eyebrow, nose and mouth regions show statistically significant larger excursions; exception must be made to the eye region, where Asians have a larger excursion of the eyelids. This is the first step to gather essential information about the ethnical differences in facial movements, a factor that should be considered as FFMT is becoming more popular worldwide.