Influence of body water distribution on skin thickness: measurements using high-frequency ultrasound

The Assessment of the Long-Term Impact of Radiotherapy on Biophysical Skin Properties in Patients after Head and Neck Cancer

Background and Objectives: Chronic radiotherapy-induced skin injury (cRISI) is an irreversible and progressive condition that can significantly impact a patient's quality of life. Despite the limited literature available on the assessment of the epidermal barrier in cRISI, there is a consensus that appropriate skincare, including the use of emollients, is the primary therapeutic approach for this group of patients. The aim of this study was to evaluate the biophysical properties of the skin during the late period (at least 90 days) following radiation therapy (RT) for head and neck cancer. Materials and Methods: This was a single-center prospective non-randomized study. It involved the analysis of 16 adult patients with head and neck cancer who underwent RT at the Greater Poland Cancer Center, along with 15 healthy volunteers. The study and control groups were matched for gender and age (p = 0.51). Clinical assessment, based on the LENT-SOMA scale, was conducted for all patients. Evaluation of the skin's biophysical properties included: an analysis of transepidermal water loss (TEWL), stratum corneum hydration (SCH), and skin visualization using high-frequency ultrasonography (HF-USG). Results: A significantly higher TEWL was observed in the irradiated area compared to the control area in the study group (p = 0.004). However, there was no statistically significant difference in SCH (p = 0.073). Additionally, no significant difference was observed in the values of TEWL and SCH in the irradiated area between the group of patients with and without clinically obvious RISI (p = 0.192 and p = 0.415, respectively). The skin thickness of the irradiated area, assessed by HF-USG, did not differ significantly from the skin thickness of the control area (p = 0.638). Furthermore, no difference in skin thickness was observed in patients with clinical features of cRISI in the irradiated and control areas (p = 0.345). The mean time after RT was 6.1 years. Conclusions: This study marks the first demonstration of epidermal barrier damage in patients in the long term following RT for head and neck cancer. The impairment of the epidermal barrier was observed independently of evident cRISI features. This observation underscores the necessity to recommend appropriate skin care, including the use of emollients, for all patients following RT. We also suggest that HF-USG examination is generally inconclusive in determining the degree of skin damage in the late period after RT.

Exploring Indicators of Subcutaneous Tissue Fluid Accumulation in Breast Cancer-Related Lymphedema Patients Using Fractal Analysis with Virtual Volume

Background: Breast cancer treatment sometimes causes a chronic swelling of the arm called breast cancer-related lymphedema (BCRL). Its progression is believed to be irreversible and is accompanied by tissue fibrosis and lipidosis, so preventing lymphedema from progressing by appropriate intervention at the site of fluid accumulation at an early stage is crucial. The tissue structure can be evaluated in real time by ultrasonography, and this study aims at assessing the ability of fractal analysis using virtual volume in detecting fluid accumulation within BCRL subcutaneous tissue via ultrasound imaging. Methods and Results: We worked with 21 women who developed BCRL (International Society of Lymphology stage II) after unilateral breast cancer treatment. Their subcutaneous tissues were scanned with an ultrasound system (Sonosite Edge II; Sonosite, Inc., FUJIFILM) using a 6- to 15-MHz linear transducer. Then, a 3-Tesla MR system was used to confirm fluid accumulation in the corresponding area of the ultrasound system. Significant differences in both H + 2 and complexity were observed among the three groups (with hyperintense area, without hyperintense area, and unaffected side) (p < 0.05). Post hoc analysis (Mann-Whitney U test; Bonferroni correction p < 0.0167) revealed a significant difference for "complexity." The evaluation of the distribution in Euclidean space showed that the variation of the distribution decreased in the order of unaffected, without hyperintense area, and with hyperintense area. Conclusion: The "complexity" of the fractal using virtual volume seems to be an effective indicator of the presence or absence of subcutaneous tissue fluid accumulation in BCRL.

Atopic Dermatitis and Water: Is There an Optimum Water Intake Level for Improving Atopic Skin?

Water is a vital nutrient with innumerable functions for every living cell. The functions of human skin include protection against dehydration of the body. Atopic dermatitis (AD) is a chronic pruritic inflammatory skin disease that presents with dry skin, erythematous and eczematous lesions, and lichenification. This paper discusses the question of whether extra water intake in children with AD affects skin hydration and the skin barrier function. Among the methods used to treat dry skin, topical leave-on products are the first-line treatment, intended to improve hydration and the skin barrier function. The effectiveness of adequate water intake as a measure to treat dry skin is still under debate. Normal skin hydration increases with dietary water intake, particularly in those with prior lower water consumption. Skin dryness in AD is instrumental to the itch and inflammation cycle, contributing to barrier impairment and aggravating disease severity and flares. Certain emollients provide significant hydration to AD skin, with relief of dryness and reduction in barrier impairment, disease severity, and flares. Further investigations are needed to evaluate the optimum water intake levels in children with AD, as important questions remain unanswered, namely, does oral hydration provide relief of skin dryness and reduce barrier impairment, disease severity, and flares; is there any additional benefit from using mineral or thermal spring water; or is there a need to specifically study the fluid/water intake in children with AD and food allergy (FA) restrictions?

Assessment of fluid removal using ultrasound, bioimpedance and anthropometry in pediatric dialysis: a pilot study

BACKGROUND

Fluid overload is associated with morbidity and mortality in children receiving dialysis. Accurate clinical assessment is difficult, and using deuterium oxide (D₂O) to measure total body water (TBW) is impractical. We investigated the use of ultrasound (US), bioimpedance spectroscopy (BIS), and anthropometry to assess fluid removal in children receiving maintenance hemodialysis (HD).

METHODS

Participants completed US, BIS, and anthropometry immediately before and 1-2 h after HD for up to five sessions. US measured inferior vena cava (IVC) diameter, lung B-lines, muscle elastography, and dermal thickness. BIS measured the volume of extracellular (ECF) and intracellular (ICF) fluid. Anthropometry included mid-upper arm, calf and ankle circumferences, and triceps skinfold thickness. D₂O was performed once pre-HD. We assessed the change in study measures pre- versus post-HD, and the correlation of change in study measures with percent change in body weight (%∆BW). We also assessed the agreement between TBW measured by BIS and D₂O.

RESULTS

Eight participants aged 3.4-18.5 years were enrolled. Comparison of pre- and post-HD measures showed significant decrease in IVC diameters, lung B-lines, dermal thickness, BIS %ECF, mid-upper arm circumference, ankle, and calf circumference. Repeated measures correlation showed significant relationships between %∆BW and changes in BIS ECF (r_rm =0.51, 95% CI 0.04, 0.80) and calf circumference (r_rm=0.80, 95% CI 0.51, 0.92). BIS TBW correlated with D₂O TBW but overestimated TBW by 2.2 L (95% LOA, -4.75 to 0.42).

CONCLUSION

BIS and calf circumference may be helpful to assess changes in fluid status in children receiving maintenance HD. IVC diameter, lung B-lines and dermal thickness are potential candidates for future studies.

Nutrition and Water

Water has numerous functions necessary for survival including cellular homeostasis, solvent properties for dissolving ions and solutes, thermoregulation, and transport of waste and nutrients. Despite the established beneficial role of water in skin physiology, the optimal methods for skin hydration and requirements for daily water consumption remain elusive. This review summarizes the cellular and molecular biology of skin hydration, the debate and current recommendations of daily water requirements, and the latest research on interventions to improve skin hydration by both internal and external means of water exposure. We also explore the chemical properties of water, such as the concept of water "hardness" and environmental pollutants, and their impact on skin physiology.

Volumetric assessment of lower limb oedema using 3D laser scanning technique: a systematic review

Clinically, oedema is described as an abnormal build-up of interstitial fluid in the body that is enough to produce palpable swelling. Its assessment offers valuable information to clinicians as this can inform management interventions; and help monitor adherence to home therapy programmes and activity levels. The aim of this systematic review is to establish the utility of 3D scanning technologies in the assessment of lower limb oedema. A computer-based search was completed in October 2020. Four studies were identified which utilised a 3D scanner to measure lower limb oedema. A review of the studies found very little evidence to support the efficacy of 3D laser scanning technology, although they show that the use of the technology is feasible. Current methods of lower leg oedema measurement have issues with reliability, practicability and time taken. There is a need for future studies to validate new methods of oedema assessment using technologies such as 3D laser scanning.

Prediction of the Presence of Fluid Accumulation in the Subcutaneous Tissue in BCRL Using Texture Analysis of Ultrasound Images

Background: Breast cancer-related lymphedema (BCRL) is a chronic swelling of the arm due to breast cancer treatment. Lymphedema is diagnosed and staged on the basis of limb circumference measurements and the patient's subjective symptoms, which have poor reproducibility and objectivity: these cannot detect any fluid accumulation in the tissue. Ultrasonography is a feasible noninvasive technique that can be used to evaluate tissue structure in real time. This study aimed to assess the ability of texture features for discriminating the presence of accumulated fluid within the subcutaneous tissue of BCRL using ultrasound (US) imaging. Methods and Results: This study included 20 women who were treated for unilateral breast cancer and who subsequently developed BCRL (International Society of Lymphology stage II). Subcutaneous tissue was scanned through an US system (Sonosite Edge II; Sonosite, Inc., FUJIFILM) using a 6- to 15-MHz linear transducer to assess the ability of texture features for discriminating the presence of accumulated fluid within the subcutaneous tissue of BCRL. Fluid accumulation was observed using a 3-Tesla MR system under double-echo steady-state conditions. There was a significant difference among the three groups (with hyperintense area, without hyperintense area, and unaffected side) in 11 of 14 textural features (p < 0.05). Post hoc analysis (Mann-Whitney U test; Bonferroni correction p < 0.0167) revealed significant differences in seven textural features within the hyperintense area. Conclusions: This study revealed that seven texture features quantified by US imaging data can provide information regarding fluid accumulation in the subcutaneous tissue of lymphedema.

The Influence of Skin Thickness on Flash Glucose Monitoring System Accuracy in Dogs with Diabetes Mellitus

Simple Summary

A flash glucose monitoring system (FGMS) has been validated for use in dogs with diabetes mellitus and diabetic ketoacidosis. It continuously measures the glucose in the interstitial fluid through a small filament (5 mm long) inserted under the skin. Interstitial glucose concentrations are reportedly comparable to whole blood glucose concentrations. However, several factors can influence the performance of interstitial sensors, including the proportion of interstitial fluid in a tissue. The influence of skin thickness on flash glucose monitoring system accuracy has not been investigated in previous studies; therefore, the aim of this study was to evaluate whether FGMS accuracy is affected by skin thickness. On the basis of our results, skin thickness seems to affect FGMS measurements; the mean bias was significantly inversely correlated (p = 0.02; r = −0.6) with the mean skin thickness, and clinical accuracy according to ISO 15197:2013 criteria was observed only in dogs with skin thickness > 5 mm, with 99% of the results falling in zone A + B of the Parkes consensus error grid analysis. In dogs with thin skin (<5 mm), the clinical accuracy was low, and the results should be interpreted with caution.

Abstract

A flash glucose monitoring system (FGMS) has been validated for use in diabetic dogs. However, it is unknown whether skin thickness affects FGMS measurements. The aim of this study was to evaluate whether FGMS accuracy is affected by skin thickness. Fourteen client-owned diabetic dogs on insulin treatment were prospectively enrolled in the study. The dogs were divided into two groups according to their ultrasound-measured skin thickness: dogs with skin thickness < 5 mm (Group 1) and dogs with skin thickness > 5 mm (Group 2). On days 1, 7 and 14, glucose curves were obtained simultaneously using the FGMS and a validated portable blood glucose meter. Paired measurements were used to calculate the mean bias and to determine accuracy according to ISO 15197:2013 criteria. The mean bias was significantly inversely correlated (p = 0.02; r = −0.6) with the mean skin thickness. Clinical accuracy was observed only in Group 2, with 99% of the results in zone A + B of the Parkes consensus error grid analysis. In conclusion, skin thickness seems to affect FGMS measurements, and the device is accurate in dogs with thicker skin (>5 mm); in dogs with thin skin (<5 mm), the clinical accuracy is low, and the results should be interpreted with caution.

Validation of Point-of-Care Ultrasound to Measure Perioperative Edema in Infants With Congenital Heart Disease

Purpose: Fluid overload is a common post-operative issue in children following cardiac surgery and is associated with increased morbidity and mortality. There is currently no gold standard for evaluating fluid status. We sought to validate the use of point-of-care ultrasound to measure skin edema in infants and assess the intra- and inter-user variability. Methods: Prospective cohort study of neonates (≤30 d/o) and infants (31 d/o to 12 m/o) undergoing cardiac surgery and neonatal controls. Skin ultrasound was performed on four body sites at baseline and daily post-operatively through post-operative day (POD) 3. Subcutaneous tissue depth was manually measured. Intra- and inter-user variability was assessed using intraclass correlation coefficient (ICC). Results: Fifty control and 22 surgical subjects underwent skin ultrasound. There was no difference between baseline surgical and control neonates. Subcutaneous tissue increased in neonates starting POD 1 with minimal improvement by POD 3. In infants, this pattern was less pronounced with near resolution by POD 3. Intra-user variability was excellent (ICC 0.95). Inter-user variability was very good (ICC 0.82). Conclusion: Point-of-care skin ultrasound is a reproducible and reliable method to measure subcutaneous tissue in infants with and without congenital heart disease. Acute increases in subcutaneous tissue suggests development of skin edema, consistent with extravascular fluid overload. There is evidence of skin edema starting POD 1 in all subjects with no substantial improvement by POD 3 in neonates. Point-of-care ultrasound could be an objective way to measure extravascular fluid overload in infants. Further research is needed to determine how extravascular fluid overload correlates to clinical outcomes.

Dermal thickness and echogenicity using DermaScan C high frequency ultrasound: Methodology and reliability testing in people with and without primary lymphoedema

BACKGROUND

DermaScan C high frequency ultrasound was investigated for image capture and analysis of dermal measures in people with and without primary lymphoedema.

METHOD

Three repeated images were taken at six sites in people without lymphoedema (NLO). Intra-rater reliability was assessed by taking three sets of measures on images from 10 people and inter-session reliability by capturing three images, lifting the probe from the skin in between. Methods were adjusted, and repeated images from four sites were taken in people with primary lymphoedema (PLO) and reliability re-assessed.

RESULTS

Intra-rater reliability in NLO and PLO for echogenicity measures were excellent (NLO ICC_(3,1) : .989; PLO .997) across all sites and specific to each site (calf: ICC_(3,1) : .989; and foot: ICC_(3,1) : .999, respectively). Inter-session reliability was moderate for NLO (ICC_(3,1) : .727), improving after method modifications for PLO (ICC_(3,1) : .916). When investigated by site, inter-session reliability was good in the foot (ICC_(3,1) : .811) and moderate in the calf (ICC_(3,1) : .616). Mean thickness analysed by site resulted in good inter-session reliability only in the foot (ICC_(3,1) .838).

CONCLUSION

Intra-rater reliability was excellent using the DermaScan C for dermal measures in people with primary lymphoedema. Inter-session reliability required particular attention to method and gain settings.

A Quantitative Method to Measure Skin Thickness in Leg Edema in Pregnant Women Using B-Scan Portable Ultrasonography: A Comparison Between Obese and Non-Obese Women

BACKGROUND This study aimed to use a portable ultrasound method to quantitatively measure skin thickness and to compare leg edema in obese and non-obese pregnant women. MATERIAL AND METHODS Thirty-six pregnant women (17 primiparas and 19 multiparas) at 27/28 and 37/38 weeks of pregnancy, with and without leg edema, had their lower leg skin thickness measured using a B-scan portable ultrasonography device (72 legs and maximum of 98 measurements). Measurements were compared between women who were obese prior to pregnancy, with a body mass index (BMI) ≥25 kg/m² and non-obese with a BMI <25 kg/m². RESULTS Skin thickness of the legs in pregnant women with edema was significantly increased compared with that in pregnant women without edema (6.4±0.3 mm vs. 4.6±0.4 mm) (p=0.0001). There was a significant correlation between the degree of pitting edema and skin thickness in all edematous legs (r=0.56; n=98; p<0.0001). The cutoff level of edema measured by portable ultrasound in non-obese pregnant women was 4.7 mm (sensitivity 83.9%, specificity 66.7%) and was 7.5 mm in obese pregnant women. Obese pregnant women with edema had a significantly increased leg skin thickness compared with non-obese pregnant women with edema (11.3±1.3 mm vs. 5.7±0.2 mm) (p<0.0001). CONCLUSIONS Portable ultrasonography is a reliable method of quantitatively measuring skin thickness of the lower leg in edema associated with pregnancy. The thickness of the skin in obese pregnant women with edema can be expected to be significantly increased compared with non-obese pregnant women with edema.

Ultrasonographic findings of re-epithelialized skin after partial-thickness burns

Background

This study aimed to investigate the difference between ultrasonographic findings of normal skin and those of re-epithelialized skin after partial-thickness burns and to evaluate the relationship between these findings and clinical outcomes.

Methods

This study retrospectively analysed the ultrasound images of re-epithelialized skin after partial-thickness burns and contralateral normal skin from January 2016 to December 2016. A total of 155 lesions from 148 patients were analysed with ultrasound images, and healing time was documented. The scar status of each lesion was evaluated through medical records and photographs. We analysed the difference in ultrasonographic findings between normal skin and re-epithelialized skin after partial-thickness burns and statistically analysed the relationship between healing time, scar status and ultrasonographic findings.

Results

The re-epithelialized skin after partial-thickness burns was significantly thicker than the contralateral normal skin, and the echogenicity was significantly lower. The ultrasound images of the re-epithelialized skin after partial-thickness burns showed the characteristic findings of low-echogenic bands (LEB), and the proportion of LEB thickness is strongly correlated with healing time. In the multivariate analysis of scar status, only the proportion of LEB thickness was statistically significant.

Conclusion

In this study, we found that there were ultrasonographic differences between re-epithelialized skin after partial-thickness burns and normal skin and that an LEB of varying thickness was formed after re-epithelialization. The thickness of the LEB in re-epithelialized skin after partial-thickness burns increased with healing time and was related to scar status.

[High-resolution ultrasonography for differential diagnosis between nodular basal carcinoma and sebaceous hyperplasia of the face: A pilot study]

BACKGROUND

Clinical differential diagnosis between incipient nodular basal carcinoma (NBC) and sebaceous hyperplasia (SH) of the face is difficult in some cases. A comparative histological analysis of these two entities led us to the hypothesis that 20MHz high-resolution ultrasonography (HRUS) may enable differentiation between NBC and SH.

PATIENTS AND METHODS

Seventy-seven facial tumours requiring histological confirmation to distinguish between NBC and SH were scanned using HRUS before excision. No other imaging technique was used. The ultrasound scans were submitted to two blinded reviewers who were asked to classify the ultrasound pictures of the tumours as either hypoechoic or isoechoic/hyperechoic. Hypoechogenicity was defined as a diagnostic criterion for NBC.

RESULTS

Reviewer response reproducibility for 2 images of the same tumour was 90%. Both reviewers agreed regarding the echogenicity classification of an image in 87.4% of cases. The sensitivity of the procedure was 90.9% for detection of NBC and 89.4% for detection of malignant lesions. Specificity was 69.6% for detection of basal cell carcinomas and 78.8% for detection of malignant lesions.

DISCUSSION

HRUS is a non-invasive examination technique with excellent sensitivity for the detection of NBC in differential diagnosis with SH. Hypoechogenicity is not specific to NBC. The sensitivity of HRUS in our study suffered as a result of ultrasonography difficulties regarding unexpected differential diagnoses of NBC as well as tumour localisation in seborrhoeic areas.

[High frequency ultrasound]

Diagnostic ultrasound has become a standard procedure in clinical dermatology. Devices with intermediate high frequencies of 7.5-15 MHz are used in dermato-oncology for the staging and postoperative care of skin tumor patients and in angiology for improved vessel diagnostics. In contrast, the high frequency ultrasound systems with 20-100 MHz probes offer a much higher resolution, yet with a lower penetration depth of about 1 cm. The main indications are the preoperative measurements of tumor thickness in malignant melanoma and other skin tumors and the assessment of inflammatory and soft tissue diseases, offering information on the course of these dermatoses and allowing therapy monitoring. This article gives an overview on technical principles, devices, mode of examination, influencing factors, interpretation of the images, indications but also limitations of this technique.

Changes in single skinfold thickness in 100 km ultramarathoners

Background

Changes in single skinfold thickness and body fat have been investigated in ultraswimmers and ultracyclists, but not in ultrarunners. The present study investigated the changes in single skinfold thickness during a 100 km ultramarathon.

Methods

Firstly, we investigated associations between prerace preparation and prerace body composition and, secondly, changes in single skinfold thickness during a 100 km ultramarathon in 219 male ultramarathoners. Changes in fat mass and skeletal muscle were estimated using anthropometric methods.

Results

Kilometers run weekly prerace and running speed during training were negatively associated with all skinfold thicknesses (P < 0.05) except for the front thigh skinfold. During the race, skinfold thickness at the pectoral (−0.1%), suprailiac (−1.8%), and calf (−0.8%) sites decreased (P < 0.05). The subjects lost 1.9 ± 1.4 kg of body mass (P < 0.001), 0.7 ± 1.0 kg of estimated skeletal muscle mass (P < 0.001), and 0.2 ± 1.3 kg of estimated fat mass (P < 0.05). The decrease in body mass was positively related to the decrease in both estimated skeletal muscle mass (r = 0.21, P = 0.0017) and estimated fat mass (r = 0.41, P < 0.0001).

Conclusion

Firstly, prerace fat mass and prerace skinfold thickness were associated with both volume and speed in running training. Secondly, during the ultramarathon, skinfold thickness decreased at the pectoral, suprailiac, and calf sites, but not at the thigh site. Percent decreases in skinfold thickness for ultrarunners was lower than the percent decreases in skinfold thickness reported for ultraswimmers and ultracyclists.

Ad libitum fluid intake leads to no leg swelling in male Ironman triathletes - an observational field study

BACKGROUND

An association between fluid intake and limb swelling has been described for 100-km ultra-marathoners. We investigated a potential development of peripheral oedemata in Ironman triathletes competing over 3.8 km swimming, 180 km cycling and 42.2 km running.

METHODS

In 15 male Ironman triathletes, fluid intake, changes in body mass, fat mass, skeletal muscle mass, limb volumes and skinfold thickness were measured. Changes in renal function, parameters of skeletal muscle damage, hematologic parameters and osmolality in both serum and urine were determined. Skinfold thicknesses at hands and feet were measured using LIPOMETER® and changes of limb volumes were measured using plethysmography.

RESULTS

The athletes consumed a total of 8.6 ± 4.4 L of fluids, equal to 0.79 ± 0.43 L/h. Body mass, skeletal muscle mass and the volume of the lower leg decreased (p <0.05), fat mass, skinfold thicknesses and the volume of the arm remained unchanged (p >0.05). The decrease in skeletal muscle mass was associated with the decrease in body mass (p <0.05). The decrease in the lower leg volume was unrelated to fluid intake (p >0.05). Haemoglobin, haematocrit and serum sodium remained unchanged (p >0.05). Osmolality in serum and urine increased (p <0.05). The change in body mass was related to post-race serum sodium concentration ([Na+]) (r = -0.52, p <0.05) and post-race serum osmolality (r = -0.60, p <0.05).

CONCLUSIONS

In these Ironman triathletes, ad libitum fluid intake maintained plasma [Na+] and plasma osmolality and led to no peripheral oedemata. The volume of the lower leg decreased and the decrease was unrelated to fluid intake. Future studies may investigate ultra-triathletes competing in a Triple Iron triathlon over 11.4 km swimming, 540 km cycling and 126.6 km running to find an association between fluid intake and the development of peripheral oedemata.

Skin viscoelasticity: physiologic mechanisms, measurement issues, and application to nursing science

Skin is the primary interface between health care providers and patients and is assessed clinically to predict physiological stability or instability. The biomechanical properties of human skin, most notably elasticity and viscoelasticity, are critical to its protective function. In this article, the authors describe the physiological basis for skin elasticity and viscoelasticity. The authors discuss the role of viscoelasticity in nursing science and consider avenues for scientific exploration of the skin's biomechanical properties, including applications in pressure ulcer research, injury, and healing. They also discuss the Cutometer® as one option for measurement of viscoelasticity in clinical and bench research protocols.

Gender variations in the optical properties of skin in murine animal models

Gender is identified as a significant source of variation in optical reflectance measurements on mouse skin, with variation in the thickness of the dermal layer being the key explanatory variable. For three different mouse strains, the thickness values of the epidermis, dermis, and hypodermis layers, as measured by histology, are correlated to optical reflectance measurements collected with elastic scattering spectroscopy (ESS). In all three strains, males are found to have up to a 50% increase in dermal thickness, resulting in increases of up to 80% in reflectance values and higher observed scattering coefficients, as compared to females. Collagen in the dermis is identified as the primary source of these differences due to its strong scattering nature; increased dermal thickness leads to a greater photon path length through the collagen, as compared to other layers, resulting in a larger scattering signal. A related increase in the observed absorption coefficient in females is also observed. These results emphasize the importance of considering gender during experimental design in studies that involve photon interaction with mouse skin. The results also elucidate the significant impact that relatively small thickness changes can have on observed optical measurements in layered tissue.

Nutrition and water: drinking eight glasses of water a day ensures proper skin hydration-myth or reality?

How-to books, beauty journals, the Internet, and the media usually recommend drinking six to eight glasses of water each day for keeping the skin hydrated, helping it look healthier, and making it less prone to wrinkles. We have found no scientific proof for this recommendation; nor is there proof, we must admit, that drinking less water does absolutely no harm. The only certainty about this issue is that, at the end of the day, we still await scientific evidence to validate what we know instinctively to be true--namely, that it is all a myth.

Principles of high-frequency ultrasonography for investigation of skin pathology

Ultrasonography is a valuable diagnostic tool widely used in medicine. During the last three decades, this non-invasive skin imaging method has been extended to dermatology. High-frequency ultrasonography with higher than 20MHz scanners is well-established for measuring tumour thickness and skin thickness when treating inflammatory skin diseases such as scleroderma or psoriasis. High-frequency ultrasonography has become extremely helpful for the preoperative assessment of skin melanoma. The correlation between ultrasonic and histological measurements of melanomas thickness is significantly similarly good using transducers of 20, 75 or 100MHz frequency (r range from 0.895 to 0.99) and better compared with transducers of 7.5MHz frequency (r=0.76). The preoperative sonographically estimated thickness of skin melanoma is sometimes overestimated, because of an underlying inflammatory infiltrate and other reasons. Assessment of skin melanoma thickness using transducers of 100MHz frequency has better agreement with histology, compared with ultrasonography with 20MHz transducers. However, the ultrasonic penetration depth is limited to 1.5mm in case of 100MHz. The newer ultrasonic techniques such as high-frequency ultrasonography and colour Doppler sonography could be used for assessment of the tumour vascularization and its metastatic potential. The wide variety of diagnostic information provided by high-frequency ultrasonography undoubtedly improves the management of oncological and inflammatory skin conditions and underlines its essential position in dermatological practice.

Effect of fluid intake on skin physiology: distinct differences between drinking mineral water and tap water

It is generally stated that drinking plenty of water has a positive influence on skin condition. However, there is no published scientific study that has investigated this matter. The aim of our exploratory 'before-after' study was to evaluate the in vivo influence of drinking more than 2 L of mineral water or ordinary tap water per day on skin physiology. Ninety-three healthy subjects were included in our prospective study. After an initial run-in phase of 2 weeks to monitor individual drinking habits, subjects had to drink 2.25 L day(-1) of either mineral water (n = 53) or tap water (n = 40) for 4 weeks. Bioengineering in vivo measurements on the volar forearm included sonographic evaluation of skin thickness and density, determination of skin surface pH, assessment of skin surface morphology, and measurement of finger circumference. Eighty-six subjects completed the study. In the mineral water group measurements revealed a statistically significant decrease in skin density. Skin thickness increased slightly, albeit not at a statistically significant level. However, when separately analysing those individuals from the mineral water group, who had routinely drunken comparably little before the start of the study, their skin thickness increased at a statistically significant level. Skin surface pH remained almost unchanged in the physiologically optimal range. In the tap water group, skin density increased significantly, while skin thickness decreased significantly. Skin surface pH decreased at a statistically significant level. While in the mineral water group finger circumference decreased significantly, measurements in the tap water group revealed a statistically significant increase. Objective skin surface morphology did not change in any group. In summary, drinking more than 2 L of water per day can have a significant impact on skin physiology. The exact effects within the skin seem to differ depending on the nature of the water ingested. Randomized, controlled, double-blind follow-up trials are warranted to confirm the findings of our exploratory pilot study.

Histological findings compared with magnetic resonance and ultrasonographic imaging in irreversible postmastectomy lymphedema: a case study

Postmastectomy edema is a current complication after axillary lymph node dissection in cases of breast cancer treatment. Staging is important in order to select those patients who can benefit from complex physical therapy (CPT). Different imaging techniques can be used to evaluate the edema. Ultrasonography (US) is a harmless, cheap, and easily applicable technique to visualize the dermal and subcutaneous tissue, but interpretation of the obtained images is not always evident. The aim of this study was to compare ultrasound images of irreversible edema with tissue histology, magnetic resonance imaging (MRI) and magnetic resonance spectroscopy (MRS). Ultrasonographic images of the edematous dermis show an homogeneous hypoechogenic dermal layer that appears on tissue histology to be less compact, due to the excess of fluid in the interstitium separating the collagen fibres and making it more transparent on light microscopy. MRI of the dermis gives a hyperintense signal, indicating the presence of fluid. In the subcutis, increase of the adipose tissue could be observed on US, MRI, and tissue histology. In the case of lymphedema, the area and perimeter of fat cells is significantly (p < 0.05) increased. Hypoechogenic areas near the muscle fascia are registered on US corresponding with epifascial fluid on MRI, and hyperechogenic branches are embedded within the adipose tissue, on tissue histology seen as large fibrotic septa enclosing adipose cells. MRI has a honeycomb picture corresponding with fluid bound to fibrosis.

Effects of an oral contraceptive containing chlormadinone and ethinylestradiol on acne-prone skin of women of different age groups: an open-label, single-centre, phase IV study

BACKGROUND AND OBJECTIVE

Acne-prone skin, a common skin condition not only in adolescents but also in adults, can significantly influence the affected individual's quality of life. The aim of this open-label, prospective, single-centre, phase IV study was to investigate the effects of an oral contraceptive containing chlormadinone 2 mg and ethinylestradiol 0.03 mg (Belara) on the physiology of acne-prone facial skin in healthy women aged 18-37 years.

METHODS

Forty-four Caucasian women requesting hormonal contraception divided into two age groups (group A: 18-27 years; group B: 28-37 years) were treated with chlormadinone/ethinylestradiol for six menstrual cycles. During each treatment phase, each subject took one tablet per day for 21 consecutive days, followed by a 7-day pill-free interval. Medication was commenced on the first day of menses. Changes in skin parameters were evaluated in terms of the clinical sum score (the primary outcome variable, calculated from the number of comedones, the number of papules/papulopustules, and the sebum secretion state), the evaluation of the pore size using standardized photography, and a range of biophysical in vivo measurements, assessed at baseline, after 12 weeks and after 24 weeks.

RESULTS

In both age groups, facial skin condition as quantified by the clinical sum score improved significantly after three and six treatment cycles, with reduced numbers of acne lesions (comedones and papules/papulopustules) and a reduction in seborrhoea. Moreover, there was a statistically significant decrease in pore size. Biophysical evaluations confirmed favourable effects of the medication on diverse skin parameters. Skin surface pH remained within the normal physiological range and there was an improvement in epidermal barrier function (as manifested by decreased transepidermal water loss from the skin of the forehead). Stratum corneum hydration increased in both age groups and the lipid content of the skin surface on the forehead decreased significantly after three treatment cycles in subjects aged 28-37 years. Ultrasound measurements verified that there was no retention of water within the dermis. There was no difference between the two age groups.

CONCLUSION

For the first time, improvements in several facial skin parameters during treatment with a combined oral contraceptive (chlormadinone/ethinyl-estradiol) were quantified by biophysical methods and a clinical sum score. The highly statistically significant improvements in clinical findings and various biophysical skin parameters observed in this study suggest that the antiandrogenic oral contraceptive chlormadinone/ethinylestradiol may be a major therapy option in women with acne-prone skin who request hormonal contraception.

Use of high-frequency ultrasonography for evaluation of skin thickness in relation to hydration status and fluid distribution at various cutaneous sites in dogs

OBJECTIVE

To assess the usefulness of high-frequency diagnostic ultrasonography for evaluation of changes of skin thickness in relation to hydration status and fluid distribution at various cutaneous sites in dogs.

ANIMALS

10 clinically normal adult dogs (6 males and 4 females) of various breeds.

PROCEDURES

Ultrasonographic examination of the skin was performed before and after hydration via IV administration of an isotonic crystalloid solution (30 mL/kg/h for 30 minutes). A 13-MHz linear-array transducer was used to obtain series of ultrasonographic images at 4 different cutaneous sites (the frontal, sacral, flank, and metatarsal regions). Weight and various clinicopathologic variables (PCV; serum osmolality; and serum total protein, albumin, and sodium concentrations) were determined before and after the infusion. These variables and ultrasonographic measurements of skin thickness before and after hydration were compared.

RESULTS

Among the 10 dogs, mean preinfusion skin thickness ranged from 2,211 microm (metatarsal region) to 3,249 microm (sacral region). Compared with preinfusion values, weight was significantly increased, whereas PCV; serum osmolality; and serum total protein, albumin, and sodium concentrations were significantly decreased after infusion. After infusion, dermal echogenicity decreased and skin thickness increased significantly by 21%, 14%, 15%, and 13% in the frontal, sacral, flank, and metatarsal regions, respectively.

CONCLUSIONS AND CLINICAL RELEVANCE

Cutaneous site and hydration were correlated with cutaneous characteristics and skin thickness determined by use of high-frequency ultrasonography in dogs. Thus, diagnostic ultrasonography may be a useful tool for the noninvasive evaluation of skin hydration in healthy dogs and in dogs with skin edema.

Ultrasonography in dermatology

Ultrasonography is an essential tool for most medical specialties; training in its use is required for dermatology residency programs in Germany. Ultrasonography is a versatile, painless, low-risk, non-invasive procedure which can be done anywhere and easily repeated; it provides real-time visual information about benign and malignant processes in the skin and subcutis. High frequency sonography with 20 MHz scanners is well-established for measuring the thickness of the skin or its tumors and assessing inflammatory skin disorders. Mid-frequency sonography with 7.5-15 MHz sounds is widely used in dermatologic oncology, both for pre-operative staging and follow-up of melanoma patients. The interpretation of sonographic images such as borders of lesions, echogenicity, artifacts and vascular patterns with duplex color sonography requires structured education and intensive training. The wide variety of diagnostic information provided by sonography underlines its essential position in certified skin cancer centers.

High frequency ultrasound assessment of skin fibrosis: clinical results

Fibrosis is a common late effect of radiotherapy treatment for cancer patients. Current clinical assessment of radiation-induced fibrosis is generally limited to clinician-based rating scales, which are usually not sufficient for quantitative and objective evaluations. Ultrasonic propagation properties of tissues are widely reported to be sensitive to the alterations of tissue compositions and structures. Based on our previous feasibility study, we used four parameters including skin thickness and three ultrasonic parameters of dermal tissues (attenuation slope [beta], integrated attenuation [IA] and integrated backscatter [IBS]) in the frequency range of 10 to 25 MHz for the assessment of skin fibrosis. Experiments were conducted on the forearm and neck skin in patients with postirradiation fibrosis in the neck region. The palpation score and stiffness of the neck soft tissue were also measured as an indication of fibrotic severity. Comparisons of the results between 38 patients and 20 control subjects showed a significantly smaller beta (p = 0.005) and a significantly larger skin thickness (p < 0.004) and IA (p = 0.04) in the neck skins of the patients. However, age-matched comparisons showed there were neither significant differences among patient subgroups with different fibrotic levels assessed using manual palpation or significant correlations between the four parameters and the overall stiffness of the neck soft tissues (p > 0.05). In conclusion, ultrasound tissue characterization may provide additional information for the assessment of postirradiation skin fibrosis in the neck region. Further studies are necessary to investigate the feasibility of applying the current measurement for differentiating the severity of skin fibrosis.

L’échographie cutanée haute résolution : utilité pour le diagnostic, le traitement et la surveillance des maladies dermatologiques

Although less precise than histological examination, high-resolution skin imaging is a noninvasive technique that provides complementary information to the clinical examination: the lesion's US structure as well as its lateral and depth extension. Ultrasonography helps in diagnosis and initial management by measuring melanoma thickness (so as to remove this lesion with safety margins) before destructive treatment (cryosurgery or radiotherapy), by showing tumor limits, or by detecting subclinical recurrence during the follow-up. In this paper, ultrasound images will be correlated with clinical and histological data in various clinical situations such as tumors, edema, cutaneous infiltration, sclerous tissues, hyperlaxity, and cutaneous aging.

Measurement of oedema in irritant-exposed skin by a dielectric technique

BACKGROUND

Easily applicable water-specific instruments measuring local oedema in skin are not available. The aim of this study is to demonstrate quantitative assessment of skin oedema with the dielectric technique by measuring increase of skin water content related to sodium lauryl sulphate (SLS)-induced irritant contact dermatitis.

METHODS

Irritant skin reaction and resulting oedema were induced by an irritant patch test on volar forearms in 12 healthy volunteers with the application of 1% SLS for 6 h. After occlusion the volunteers were divided into two groups: the patch test site of group I (six volunteers) received no treatment other than a base cream for the skin reaction, while for group II (six volunteers) a strong corticosteroid (clobetasol propionate) was applied on the irritant skin. During a follow-up of 72 h, erythema was scored visually, and irritant-induced oedema was measured with a novel water-specific instrument MoistureMeter-D.

RESULTS

In the untreated irritant skin, a maximum increase of 45% in skin water content was found at 10 h postocclusion and water content was still elevated at 72 h. With these persons, the degree of oedema agreed well with the ultrasound-measured skin thickness (P=0.053). In the corticosteroid-treated skin, an increase of 8% in water content was measured during 72 h but there was no correlation between oedema and skin thickness. There was no correlation between erythema and oedema in untreated or corticosteroid-treated skin.

CONCLUSION

The new instrument can easily be applied for noninvasive quantitative evaluation of local oedema and fluid retention in irritant-exposed skin.

Use of High-Resolution, High-Frequency Diagnostic Ultrasound to Investigate the Pathogenesis of Pressure Ulcer Development

OBJECTIVES

To investigate the pathogenesis of pressure ulcers utilizing high-resolution ultrasound and to explore the utility of this technology for the detection of incipient pressure ulcers prior to visual clinical signs.

DESIGN

An observational prospective study comparing high-resolution ultrasound images obtained from 119 long-term-care facility residents determined to be at risk for pressure ulcer development (Braden Scale score of 18 or less) with images obtained from 15 healthy volunteers (medical students and medical residents). Common pressure ulcer sites were scanned, including the heels, sacrum, and ischial tuberosity.

SETTING

A medical center and a long-term-care facility.

INTERVENTION

Anatomic sites universally accepted as at risk for pressure ulcer development were scanned using high-resolution ultrasound; the sites did not have visual evidence of skin breakdown. The images obtained from the long-term-care facility residents were compared with images considered normal that were obtained from healthy volunteers. In addition, documentation of the clinical assessment finding for erythema was reviewed, recorded, and compared with the high-resolution ultrasound finding for each specific site.

MEASUREMENTS

The images obtained were classified as not readable, normal, or abnormal. The images classified as abnormal were further classified by depth of abnormal finding: pattern 1 (deep) or pattern 2 (superficial). The images classified with the abnormal finding pattern 1 (deep) were further classified and subdivided by anatomic location of abnormal finding(s): subgroup 1, abnormal findings in the subdermal area only; subgroup 2, subdermal and dermal abnormal findings; and subgroup 3, subdermal, dermal, and subepidermal edema. Pattern 2 (superficial) included images with abnormal findings limited to the dermal/epidermal junction.

RESULTS

630 (55.3%) of the images obtained from the long-term-care residents were different from the images obtained from the healthy volunteers. The healthy volunteers' images classified as normal had the expected ultrasound findings for homogeneous pattern of ultrasound reflections, allowing for visualization of various skin layers (epidermis, superficial papillary dermis, deep reticular dermis, and hypodermis) and subcutaneous tissue (subdermal). However, many images (55.3%) obtained from the residents at risk for pressure ulcer development had patterns where areas within the various skin layers were not visible, interrupted by areas indicative of fluid or edema. Moreover, most images (79.7%) with abnormal ultrasound patterns did not have documentation of erythema.

CONCLUSION

High-resolution ultrasound is an effective tool for the investigation of skin and soft tissue changes consistent with the documented pathogenesis of pressure ulcers. A progressive process for pressure ulcer development from deep subdermal layers to superficial dermal then epidermal layers can be inferred. Dermal edema was only present with subdermal edema. In other words, there was never evidence of dermal edema in the absence of subdermal edema. A better understanding of the pathogenesis of pressure ulcers through the use of high-resolution ultrasound to detect soft tissue damage and edema before visible clinical signs could lead to earlier and more focused pressure ulcer prevention programs, resulting in reduced pain and suffering for improved patient quality of life and wound care cost savings.

Evaluation of the atrophogenic potential of different glucocorticoids using optical coherence tomography, 20-MHz ultrasound and profilometry; a double-blind, placebo-controlled trial

BACKGROUND

Skin atrophy is one of the main side-effects of topical corticosteroid therapy. Although the use of high-frequency ultrasound is an established method that has been studied previously, it allows measurements of the slow-reacting dermal thickness only.

OBJECTIVES

To investigate the decreasing epidermal thickness, which occurs earlier, we used optical coherence tomography (OCT), a high-resolution noninvasive imaging technique, and compared it with 20-MHz ultrasound and profilometry.

PATIENTS/METHODS

In this double-blind placebo-controlled trial 20 healthy volunteers applied four different corticosteroids and the cream base formulation as placebo to the volar part of both arms once a day over a 4-week period. The epidermal thickness, the dermal thickness and the skin surface roughness were assessed using OCT, high-frequency ultrasound and profilometry.

RESULTS

Each of the three methods allowed the detection and monitoring of significant corticosteroid-induced skin atrophy and its reversibility. The changes correlated with the potency of the steroids. The epidermal thickness decreased significantly in all test areas, even in the placebo and the untreated fields. As expected, the reduction in epidermal thickness was more pronounced and could be detected earlier by OCT than the reduction of dermal thickness using ultrasound. The epidermal surface roughness investigated using profilometry showed a slight smoothing.

CONCLUSIONS

OCT allows a simple, fast and noninvasive in vivo measurement of the epidermal thickness. To evaluate the atrophogenic potential of corticosteroids it is more suitable than high-frequency ultrasound as epidermal thickness decreases earlier. In addition, epidermal thickness is a more sensitive indicator of steroid atrophy as the degree of thinning is much higher compared with the dermal atrophy. Profilometry might give further information; however, it would not be suitable for clinical use as the results were generally less pronounced. In the future, OCT might be useful to detect corticosteroid-induced side-effects at the beginning for monitoring the therapy.

The effect of local anaesthetic cream (EMLA®) applied with an occlusive dressing on skin thickness. Does it matter?

EMLA cream is used in plastic surgery as a topical anaesthetic to harvest split skin grafts. It has been observed that the skin appears pale and oedematous after the application of EMLA. The aim our study was to determine the effect of EMLA with an occlusive dressing on skin thickness using a high frequency ultrasound. Twenty volunteers took part in this study after approval from the ethics committee. An area of skin was marked on both thighs and the skin thickness of each, measured using ultrasound. EMLA with an occlusive dressing was applied to one thigh. This was removed after at least 2 h of application time but at different time points and skin thickness of each thigh measured again. Data was analysed using t-test and Pearson's correlation. Mean age in years +/- SD (range) was 36.1 +/- 12.1 (23 - 61). Male:female ratio was 8:12. Mean skin thickness +/- SEM increased from 1.86 +/- 0.055 mm prior to EMLA application to 1.96 +/- 0.051 mm post-EMLA application p= 0.02. There was a significant correlation between the increase in skin thickness and duration of application of EMLA cream (p = <0.001, R2 = 0.59). The results conclude that EMLA applied under an occlusive dressing has an effect on skin tissue thickness and any surgeon who harvests split skin grafts under EMLA should be aware of this. Further research is needed to compare laser treatments performed under local anaesthetic creams against general anaesthesia as an increase in skin thickness may affect the depth of laser penetration.

Aquaporins in development -- a review

Water homeostasis during fetal development is of crucial physiologic importance. It depends upon maternal fetal fluid exchange at the placenta and fetal membranes, and some exchange between fetus and amniotic fluid can occur across the skin before full keratinization. Lungs only grow and develop normally with fluid secretion, and there is evidence that cerebral spinal fluid formation is important in normal brain development. The aquaporins are a growing family of molecular water channels, the ontogeny of which is starting to be explored. One question that is of particular importance is how well does the rodent (mouse, rat) fetus serve as a model for long-gestation mammals such as sheep and human? This is particularly important for organs such as the lung and the kidney, whose development before birth is very much less in rodents than in the long-gestation species.

Common denominators for the low-cost management of leg conditions

Diseases of blood supply and drainage of the leg are common, and they frequently contribute to poverty. Management must include self-help low-cost therapy. The phlebologist, lymphologist, angiologist, or dermatologist must seek to distill their knowledge for the health worker in the general health services. Such knowledge should focus on the venous system, which is amenable to simple maneuvers such as breathing, elevation, and movement. However, the mechanisms underlying the functions of the blood vessels and lymphatics and the organ they supply or drain are inextricably interwoven. Care of the veins, the lymphatics, and the epidermis depends on attention to each together and at the same time. New knowledge of cytokines produced by the epidermis and their effects on angiogenesis and permeability suggest that care of the epidermis by washing and emollients has equal value as elevation and movement. Such maneuvers cost little and are usually available.

High-frequency ultrasonography of the skin of clinically normal dogs

OBJECTIVE

To assess the applicability of high-frequency diagnostic ultrasonography for evaluation and accurate measurement of the skin thickness of clinically normal dogs.

ANIMALS

26 healthy dogs (12 sexually intact males, 13 sexually intact females, and 1 spayed female) of various breeds and ages.

PROCEDURE

Ultrasonographic examination of the skin and histomorphometric analysis of skin biopsy specimens obtained from the same site were performed. A 13-MHz linear-array transducer was used to obtain a series of ultrasonographic images of the skin in the flank region; images were analyzed and measured by use of imaging software. Cutaneous biopsy specimens were placed in fixative and then stained with H&E and Masson trichrome stains. Histomorphometric analysis was performed by use of an image analyzer. Thickness of the epidermis and dermis of each specimen was evaluated by use of a semiautomatic procedure of quantification. Data obtained from ultrasonographic and histologic measurements were compared by use of the Pearson correlation test.

RESULTS

The ultrasonographic pattern of canine skin was consistently characterized by 3 distinct, defined echogenic layers corresponding to the epidermal entry echo, epidermis and dermis, and subcutaneous tissues. A positive correlation was found between ultrasonographic and histologic measurements of skin thickness.

CONCLUSIONS AND CLINICAL RELEVANCE

Comparison between ultrasonographic and histologic appearance of the skin revealed that layering of canine skin (ie, epidermis and dermis) and the subcutaneous tissues may be recognized and measured by use of high-frequency ultrasonography. Thus, diagnostic ultrasonography may be a useful tool for the noninvasive evaluation of cutaneous disorders in dogs.

Changes in body water distribution during treatment with inhaled steroid in pre-school children

PRIMARY OBJECTIVE

The study aimed to examine the changes in water distribution in the soft tissue during systemic steroid activity.

RESEARCH DESIGN

A three-way cross-over, randomized, placebo-controlled, double-blind trial was used, including 4 weeks of fluticasone propionate pMDI 200 microg b.i.d. delivered via Babyhaler, budesonide pressurized metered dose inhaler (pMDI) 200 microg b.i.d. delivered via Nebuchamber and placebo. Spacers were primed before use. In total, 40 children aged 1-3 years, with mild intermittent asthma were included. Twenty-five of the children completed all three treatments. At the end of each treatment period body impedance and skin ultrasonography were measured.

METHODS AND PROCEDURES

We measured changes in water content of the soft tissues by two methods. Skin ultrasonography was used to detect small changes in dermal water content, and bioelectrical impedance was used to assess body water content and distribution.

MAIN OUTCOMES AND RESULTS

We found an increase in skin density of the shin from fluticasone as measured by ultrasonography (p = 0.01). There was a tendency for a consistent elevation of impedance parameters from active treatments compared to placebo although overall this effect was not statistically significant (0.1 < p < 0.2). However, sub-analyses indicated a significant effect on whole-body and leg impedance from budesonide treatment (p < 0.05).

CONCLUSION

Decreased growth during inhaled steroid treatment seems to partly reflect generalized changes in body water.

Effects of 1-year intermittent treatment with topical tacrolimus monotherapy on skin collagen synthesis in patients with atopic dermatitis

BACKGROUND

Topical corticosteroids decrease collagen synthesis during short-term treatment and can induce skin atrophy when applied over the long term. In contrast, short-term tacrolimus ointment therapy does not affect collagen synthesis.

OBJECTIVES

Our aim was to evaluate the long-term effects of 0.1% tacrolimus ointment on collagen synthesis and on skin thickness in adults with moderate to severe atopic dermatitis (AD) and to compare the findings with the effects of conventional steroid-based therapy.

METHODS

Fifty-six patients with AD were treated with 0.1% tacrolimus ointment in a 1-year, open-label, prospective clinical trial. Thirty-six patients with AD applied conventional steroid-based therapy and 27 healthy subjects were recruited as controls. The primary endpoint was the change in levels of procollagen propeptides I and III measured by radioimmunoassay between baseline and month 12. Additional endpoints included the change in skin thickness measured by ultrasound between baseline and month 12.

RESULTS

Procollagen propeptide baseline values were significantly lower in the group to be treated with tacrolimus ointment than in healthy controls. One-year treatment with tacrolimus ointment was associated with an increase in collagen synthesis; the median increase in combined procollagen propeptide levels was 272 micro g L-1 (+ 140.9%, P < 0.001) and was accompanied by a significant increase in skin thickness. In three patients with visible skin atrophy, this condition ameliorated. Corticosteroid-based therapy had no significant effect on collagen synthesis; the median increase in combined procollagen propeptide levels was 11 micro g L-1 (+ 3.9%). A significant reduction in skin thickness was demonstrated.

CONCLUSIONS

Long-term tacrolimus ointment therapy in patients with AD is nonatrophogenic and reverses corticosteroid-induced skin atrophy.