Changes in endothelial cell mass, luminal volume and capillary number in the gravitational syndrome

The histopathological changes in the skin of 31 patients with the gravitational syndrome and 10 normal control subjects were studied. To quantify the clinical severity of the syndrome, a new index of severity was used. Histometric evaluation of the cutaneous vasculature was performed on biopsies taken from the edge of the ulcers in the 31 patients and from the medical aspect of the lower legs in control subjects. Endothelial cell mass did not correlate with the clinical index of disease severity, suggesting that angiogenesis did not necessarily signal healing. The mean luminal volume appeared to be of greater prognostic value as there was a significant negative correlation of this parameter with the index of clinical severity. The degree of epidermal hyperplasia was found to be related to both the amount of inflammatory cell infiltrate present and the endothelial cell mass per unit tissue volume. The results also showed that the clinical index of disease severity was positively correlated to the mean epidermal thickness. The quantitative evaluation of biopsy material can be used to provide prognostic information in the gravitational syndrome.     

Dose—response relationships for topically applied antigens

Patch-test responses to serially diluted nickel sulphate and potassium dichromate solutions in patients with nickel and chrome sensitivity were assessed by pulsed A-scan ultrasound to determine skin thickness and laser-Doppler flowmeter techniques to evaluate blood flow, as well as clinical scoring. There was a relationship between the dose of antigen and the test responses as measured by ultrasound and laser-Doppler flowmeter techniques in both nickel and chrome sensitive patients. Our data suggest that both techniques may be useful in the detection of allergic contact dermatitis in which there is a doubtful patch-test reaction as well as in experimental sensitization studies.     

Topical retinoic acid for treatment of solar damage

Twenty patients with chronic solar damage of the skin were entered in a double-blind, within-patient trial to compare the effect of 0.05% tretinoin cream with a placebo applied once daily for 12 weeks. Sixteen completed the study. Clinical assessment of the individual signs of solar damage were recorded on separate visual analogue scales. After 12 weeks, there were significant improvements in fine wrinkling around the eyes, crease lines around the mouth and cheeks, wrinkling on the dorsum of the hands and yellow discoloration. Overall, 14 of the tretinoin-treated sides were judged to have improved compared to only two of the placebo-treated sides (P = 0.011). Measurement of skin thickness by pulsed A-scan ultrasound revealed that the sides treated with tretinoin were significantly thicker than the placebo-treated sides (P = 0.019). Skin biopsies taken before and after treatment showed an increase in mean epidermal thickness with tretinoin treatment (P = 0.019). The clinical signs of improvement persisted at the follow-up assessment performed 4 weeks after cessation of therapy.     

The use of A-scan ultrasound in the assessment of small skin tumours

This study describes the use of A-scan ultrasound for the measurement and characterization of tumour tissue in small skin tumours--basal cell carcinoma, melanocytic naevus, hypertrophic scars and intraepidermal epithelioma. Assessment of the A-scan traces by measurement of: (i) the amplitude of echoes within the area of interest; (ii) the density (number per unit depth) of these echoes; (iii) the regularity of spacing and amplitude of the echoes, and (iv) the amplitude of echoes beneath the area of interest, was used to assist in the differential diagnosis. The results show significant differences in echo amplitude between all the tumours and normal skin. When the tumour A-scan traces were analysed the results indicated that the best discriminating feature between tumours was that of amplitude, followed by regularity, density, non-normalized thickness and finally amplitude of echoes from beneath the tumour. Ultrasound-derived skin thickness measurements were compared to histological measurements for the lesions, and an excellent correlation was found (r = 0.96). It was considered that the A-scan ultrasound investigation of small tumours of the skin was able to provide information on the nature of the tissues contained and may assist in their differential diagnosis.     

Skin thickness measurement by pulsed ultrasound; its reproducibility, validation and variability

The reproducibility of the pulsed ultrasound technique for the determination of skin thickness was investigated, using two independent observers. No systematic difference was found and a high correlation was obtained. Studies were also undertaken to validate the pulsed ultrasound technique as a measure of true skin thickness. Skin thickness determined in vitro was found to be greater than when in vivo determinations were made by either the pulsed ultrasound or a xeroradiographic technique, probably due to the release of in vivo tension within the dermis after excision. Skin thickness was found to increase linearly with age up to the age of 20 years and to decrease linearly with age subsequently. Differences in skin thickness between the sexes and in different sites of the body were demonstrated.     

Skin susceptibility in uninvolved skin of hand eczema patients and healthy controls

Basic physiological characteristics were examined in the uninvolved skin of 39 patients with hand eczema and in 39 healthy controls. Susceptibility to sodium lauryl sulphate (SLS)-induced irritant dermatitis was evaluated by the application of a single 24-h SLS patch test to the upper arm. Transepidermal water loss (TEWL) was measured by an evaporimeter, skin thickness by ultrasound A-scan, blood flow by laser-Doppler flowmetry and skin colour by a chroma meter using the L*a*b* system of the Commission Internationale de l'Eclairage (CIE). No difference in basal TEWL values was found between patients and controls. A decreased skin thickness was found in those with hand eczema as compared to the controls. The hand eczema patients had significantly increased L* and decreased b*-values compared to controls, indicating a more 'fair' skin. Susceptibility to SLS was increased only in patients with acute eczema, indicating that the presence of an active eczema increases the reactivity to irritants of distant uninvolved skin.     

Quantification of cutaneous oedema in patch test reactions by measurement of skin thickness with high-frequency pulsed ultrasound

69 doubtful and positive patch test readings (?+21, +23, ++ 18, +++7) in 15 contact dermatitis patients were studied by measurement of skin thickness as an expression of allergic oedema. Exposed skin was compared with a regional control. Skin thickness was measured by 15 MHz pulsed ultrasound (A-scan) to 0.1 mm accuracy. The ?+, +, ++, and +++ reactions could be separated by measurements of absolute difference in thickness (p < 0.001, p<0.001, p<0.02) between exposed and non-exposed skin; the mean increases were 0.14, 0.49, 0.93, and 1.37 mm. The ?+, +, and ++ reactions, but not the +++ reactions, could also be separated by measurements of relative increase in skin thickness (p<0.001, p<0.001, n.s.); the mean increases were 7%, 25%, 50% and 55%. The normal thickness of the skin of the back was shown to have increased (p<0.02) in patients with +++ reactions only. It is concluded that the high-frequency ultrasound method is suitable for quantification of doubtful and positive patch test reactions. The +++ reactions are probably explained by the normal thick skin of the back, and they need no separate recording in patch testing. Standards of increase in skin thickness in doubtful and positive patch tests are defined: absolute increase (mm) was ?+≤0.2; +0.3–0.7; ++ 0.8–1.3 (+++≥ 1.4); relative increases were?+ < 15%; +15–45%, ++(+++ included)>45%.     

Basal transepidermal water loss, skin thickness, skin blood flow and skin colour in relation to sodium-lauryl-sulphate- induced irritation in normal skin

The influence of basal transepidermal water loss (TEWL), skin thickness, blood flow and skin colour on susceptibility to sodium-lauryl-sulphate(SLS)-induced irritant contact dermatitis was studied in 70 healthy volunteers. SLS 0.5% was applied as a patch test. For assessment of basal values and skin response to SLS, bioengineering methods were used: TEWL was measured by an evaporimeter, skin thickness by ultrasound A-scan, blood flow by laser Doppler flowmetry, and skin colour by a colorimeter, using the L*a*b* system of the Commission Internationale de l'Eclairage (CIE). By use of multiple regression analysis, it was demonstrated that basal TEWL was substantially related to skin susceptibility to SLS, high basal TEWL predicting an increased susceptibility to SLS. Also increased light reflection from the skin, indicating a 'fair' skin, was found to be associated with increased susceptibility to SLS.     

The effects of an abrasive agent on normal skin and on photoaged skin in comparison with topical tretinoin

Two studies were designed to assess the effect of abrasive preparations on the skin and to test the specificity of the effect of topical tretinoin in the management of chronic photodamage to the skin. In the first study two abrasive preparations (Brasivol fine and Brasivol medium) were compared with white soft paraffin and no treatment in eight volunteer subjects for their effects on the epidermis. The study was conducted over 3 days and measurements were taken of the effects on dansyl chloride-induced fluorescence to assess desquamation, epidermal thickness, and the tritiated thymidine autoradiographic labelling index. The abrasives were found to increase the desquamation rate significantly and to increase epidermal thickness and the epidermal labelling index compared to white soft paraffin and no treatment. In the second study the effect of one of the abrasive preparations (Brasivol medium) was compared with 0.05% tretinoin cream (Retin A) on the photodamaged skin of the dorsal aspects of the forearms of 12 subjects over an 8-week period. Cutaneous blood flow measured by the laser-Doppler flowmeter was found to be significantly increased in the abrasive-treated sites, but there was only a non-significant trend to increased blood flow in the tretinoin-treated sites. Measurements of skin thickness using pulsed A-scan ultrasound demonstrated that both treatments produced significant increases in thickness over the 8-week period but the increase was greater for the abrasive treated site. Measurements of the skin extensibility at the treated sites were made using a uniaxial extensometer. Forces needed for 30% skin extension were increased in the abrasive-treated sites only. Measurements of epidermal thickness and of [3H]-thymidine autoradiographic labelling indices showed greater increases in the abrasive-treated sites than in tretinoin-treated sites compared to untreated sites, but these increases were not statistically significant. No significant inflammation and no changes in the degree of elastosis or the presence of a 'repair zone' were found in any of the post-treatment biopsies. The results indicate that some of the changes produced in the skin by topical tretinoin that are taken to indicate a specific antiphotoageing effect may not in fact be specific and can be achieved by an abrasive preparation.     

Skin reactions to irritants assessed by non-invasive bioengineering methods

Pathophysiological components of irritant contact dermatitis caused by 3 chemically-different irritants were investigated. 20 healthy volunteers were patch tested with sodium lauryl sulphate, nonanoic acid and hydrochloric acid on the flexor side of the upper arm. The skin response was evaluated after 24, 48 and 96 h by visual scoring and measured by the following bioengineering methods: transepidermal water loss measurement, electrical conductance for measurement of skin hydration, laser Doppler flowmetry for measurement of cutaneous blood flow and 20 MHz ultrasound A-scan for measurement of skin thickness. In spite of homogeneous inflammatory responses, significant differences in the severity of the injury to the skin barrier function caused by the different irritants were found. Also significant differences between irritants were found in the time course of development of maximum irritant reactions. Bioengineering methods indicating inflammatory responses (measurement of blood flow and skin thickness) were helpful in quantifying the irritant response in general, while bioengineering methods indicating epidermal damage (measurement of TEWL and electrical conductance) were helpful in classifying the individual irritants.     

Pulsed ultrasound measurements of depth and regression of basal cell carcinomas after photodynamic therapy: relationship to probability of 1-year local control

BACKGROUND: The regression of clinical basal cell carcinoma (BCC) after photodynamic therapy (PDT) is poorly understood, but is potentially important when, as is increasingly the case, a second treatment is contemplated. High-frequency pulsed ultrasound provides noninvasive information on skin and lesion thickness. OBJECTIVES: To relate pulsed ultrasound measurements before and after PDT to the probability of local control of BCC by PDT. METHODS: Skin thickness and lesion thickness were measured by 20-MHz pulsed ultrasound in 181 patients diagnosed as having BCC. Maximal lesion thickness was determined by repeatedly sampling the BCCs. Measurements were made immediately prior to PDT with aminolaevulinic acid plus 630 nm visible light, and then at 1, 6 and 12 months. RESULTS: Skin thickness in individual patients did not vary with time in this study (mean +/- SD 2.3 +/- 0.6 mm; P = 0.8). In contrast, BCC mean +/- SD maximal thickness 4-6 weeks after PDT was significantly smaller than pretreatment (0.6 +/- 0.8 mm vs. 1.3 +/- 0.8 mm; P < 0.001). The overall probability of 1-year local control fell from 85% when only BCCs 相似文献   

Reduced skin thickness: a new minor diagnostic criterion for the classical and hypermobility types of Ehlers-Danlos syndrome

BACKGROUND: The diagnosis of Ehlers-Danlos syndrome (EDS) is mainly based on clinical criteria, although in some instances a sound molecular diagnosis is available. Clinical signs can be divided into two categories: one with high diagnostic specificity and the other with low specificity. Despite the fact that reduced skin thickness is one of the dermatological features in patients with EDS, this issue has not been analysed in greater detail. OBJECTIVES: To determine skin thickness in patients with the classical and the hypermobility types of EDS. METHODS: In 21 patients with classical type of EDS and in nine patients with hypermobility type of EDS, skin thickness was analysed at different body sites by cross-sectional b-mode scans obtained with a 20-MHz ultrasound system. RESULTS: We found a significant decrease in skin thickness in both types of EDS, which was highest at the chest and at the distal part of the lower leg. CONCLUSIONS: We propose that the reduced thickness of the dermis as determined by high-resolution 20-MHz ultrasound can be used as a new minor criterion in the diagnosis of the classical and the hypermobility types of EDS.     

The effect of area of application on the intensity of response to a cutaneous irritant

The intensity of the cutaneous response was assessed after application of a standard irritant to increasing areas of normal forearm skin. Twenty subjects were tested to determine the minimal irritant dose (MID) to dilutions of aqueous sodium dodecyl sulphate. Each subject was then treated under occlusion for a period of 24 h with different areas of filter paper (9, 25, 100, 225 and 400 mm2) soaked with the concentration required to give the individual's MID. At 25 and 48 h the degree of erythema was assessed using a 0-4 arbitrary scale, a 10-cm visual analogue scale (VAS) and an erythema meter. Cutaneous blood flow was measured with a laser-Doppler device and cutaneous oedema measured by pulsed A-scan ultrasound. The results at 25 and 48 h were almost identical. Both forms of visual assessment (arbitrary scale and VAS) showed an increase in perceived erythema with increasing area and this was confirmed by the erythema meter. Further area-related changes were noted with both cutaneous blood flow and ultrasound measurements.     

ULTRASOUND IMAGING OF PSORIATIC SKIN: A NONINVASIVE TECHNIQUE TO EVALUATE TREATMENT OF PSORIASIS

Background. The aim of our study was to image psoriasis plaques by ultrasound to assess the changes in psoriasis and to measure and quantify them objectively. Materials and Methods. Thirty-one psoriasis plaques were studied in 19 patients. Measurements of skin thickness were obtained with a high resolution B-mode echographic system. Results. Some changes were seen in psoriatic skin. A new structural element was observed: a wide subepidermal nonechogenic band. The other changes were a decrease in dermal echoes that were less intense and less dense, and an increase in the epidermal and dermal skin thicknesses. The skin thickness was increased in all psoriasis plaques as compared to apparently normal skin (P < 0.001). The average increase was 67% for whole skin and 200% for epidermis. Conclusions. Ultrasound imaging of psoriatic skin allowed the identification of different skin changes induced by psoriasis, and particularly, the differentiation between epidermal and dermal alterations. We presume that epidermal thickness reflects epidermal proliferation and desquamation, and the increase in the dermal and whole skin thickness reflects infiltration. We feel that ultrasound imaging of psoriatic skin is a quantitative method that is as easy and noninvasive as the psoriasis area and severity index (PASI). It could be used for following up patients with psoriasis and could achieve widespread use, especially in research protocols.     

Ultrasound investigation of port wine stains

Congenital capillary malformation, or port wine stains (PWS), have been treated with the pulsed dye laser since the late 1980s. Some studies have shown better results when the malformation has been located on the lateral face, forehead, neck, trunk or shoulder and inferior results, with more treatments required, when it is located on the central face area, dermatome V2 or the extremities. The purpose of this study was to determine the depth of the lesion in various locations. A total of 55 patients with untreated PWS were investigated with a high-resolution 20 MHz ultrasound system. The mean maximum depth of all PWS that were measurable (45 out of 55) was 1.00 mm (+/- 0.50 SD), with a range of 0.2-3.7 mm. Lesions located on the forehead (1.26 +/- 0.44 mm) and on the medial face (1.23 +/- 0.65 mm), were deeper than lesions on the trunk and extremities. PWS involving areas that respond poorly to treatment were on average 0.14 mm deeper than PWS involving areas that responded well. The depth of the PWS, as determined with high-resolution ultrasound, seems to correlate only to some degree with the response to pulsed dye laser treatment. Since this treatment, with its superficial penetration, cannot reach the deeper vessels of a PWS, skin ultrasound could be a good complement in the prognostic investigation as well as for planning treatment.     

Assessment of the duration of action of terfenadine on histamine induced weals

In this study we aimed to quantify the reduction in area, perimeter and thickness of histamine induced weals 12, 18 and 24 h after a single oral dose of 120 mg terfenadine. Ten healthy volunteers were given 120 mg of terfenadine or placebo in a double-blind randomized two-period cross-over study. Twenty micrograms of histamine were then injected intradermally at 12, 18, and 24 h. The thickness of the resulting weal was measured by an A-scan pulsed ultrasound device. The area and perimeter of the resulting weal and flare were measured by tracing onto acetate sheets and using a digitizing tablet linked to a microcomputer. Just before each dose of histamine was injected, blood was taken to measure the level of the major metabolite of terfenadine. There was a significant difference between terfenadine 120 mg and placebo in the area and perimeter of the weal and the area and perimeter of the weal and flare at 12, 18 and 24 h, but no significant difference in weal thickness. Thus, terfenadine suppresses the wealing response caused by intradermally injected histamine over a 24 h period. It may be possible, therefore, to use a once daily dose of terfenadine.     

The use of high-frequency diagnostic ultrasound to investigate the effect of hormone replacement therapy on skin thickness

Background/aims: Previous investigations have suggested that hormone replacement therapy (HRT) could have a positive effect on the maintenance of skin thickness post-menopause. Previous skin measurement devices have proved variable in their accuracy and ease of use. This investigation assessed the effect of HRT on the skin in a noninvasive way, using high-frequency diagnostic ultrasound.
Method: The study was a cross-sectional observational study, carried out at a menopause and gynaecology outpatient's clinic. A total of 84 women (comprising 34 HRT users, 25 post-menopausal controls, and 25 premenopausal controls) took part in the study. Each volunteer was scanned using diagnostic ultrasound on the arm. Skin thickness measurements were made from each scan using computerised image analysis.
Results: Skin thickness was shown to be greater in the HRT group than in the post-menopausal controls ( P <0.01).
Conclusions: High-frequency diagnostic ultrasound proved to be a useful clinical tool and showed that HRT appears to help maintain skin thickness in menopause.     

High-frequency ultrasound measurement of patch test reactions

53 patients who produced 34 positive patch test reactions (+/- 15, +10, ++4, +++5) had their reactions read by a high-frequency pulsed ultrasonic (A-scan) dermal depth detector with a resolution of 0.05 mm. The positive reactions were compared with both random and regional controls. The machine could not differentiate between + or +/- reactions from the control readings. However, for 75% of ++ cases and 80% of +++ cases, a significant change was confirmed by the detector. It is concluded that the high-frequency ultrasound method is of little use in confirming or quantifying of positive patch test results.     

Ultrasound biomicroscopy in the diagnosis of skin diseases

Ultrasound scanning is becoming an important diagnostic tool in dermatology. The major advantages of this technique are its non invasive non-ionizing nature and its relatively low cost. We aimed to evaluate the accuracy of ultrasound biomicroscopy (UBM) in the diagnosis of eight skin disorders namely, morphea, keloid, lichen planus, chronic eczema, psoriasis, port wine stain, seborrheic keratosis, and photo-aged skin, through correlation of its findings with clinical and pathological assessment. Fifty seven patients with the above diseases were examined by ultrasound biomicroscopy (UBM). Two areas, one of normal skin and the other from lesional skin, were examined for each patient. Skin biopsies were taken from the same lesion examined by UBM. In morphea, the dermal echogenicity was increased and the thickness of morphea plaques correlated significantly with disease severity. Keloids appeared as low echogenic images. In lichen planus and chronic eczema the dermis appeared as sound shadow. In psoriasis, an intermediate zone between the epidermis and dermis (B zone) was detected. Its thickness correlated significantly with the PASI score. Port wine stain lesions appeared hypoechoic. Seborrheic keratosis appeared as a sound shadow. In photo-aged skin a subepidermal low echogenic band (SLEB) was detected. We conclude that UBM is a non-invasive diagnostic tool in dermatology which can be used to give valuable information about disease progress and the effectiveness of therapy.