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The currently used 8% fragrance mix (FM I) does not identify all patients with a positive history of adverse reactions to fragrances. A new FM II with 6 frequently used chemicals was evaluated in 1701 consecutive patients patch tested in 6 dermatological centres in Europe. FM II was tested in 3 concentrations - 28% FM II contained 5% hydroxyisohexyl 3-cyclohexene carboxaldehyde (Lyral), 2% citral, 5% farnesol, 5% coumarin, 1% citronellol and 10%alpha-hexyl-cinnamic aldehyde; in 14% FM II, the single constituents' concentration was lowered to 50% and in 2.8% FM II to 10%. Each patient was classified regarding a history of adverse reactions to fragrances: certain, probable, questionable, none. Positive reactions to FM I occurred in 6.5% of the patients. Positive reactions to FM II were dose-dependent and increased from 1.3% (2.8% FM II), through 2.9% (14% FM II) to 4.1% (28% FM II). Reactions classified as doubtful or irritant varied considerably between the 6 centres, with a mean value of 7.2% for FM I and means ranging from 1.8% to 10.6% for FM II. 8.7% of the tested patients had a certain fragrance history. Of these, 25.2% were positive to FM I; reactivity to FM II was again dose-dependent and ranged from 8.1% to 17.6% in this subgroup. Comparing 2 groups of history - certain and none - values for sensitivity and specificity were calculated: sensitivity: FM I, 25.2%; 2.8% FM II, 8.1%; 14% FM II, 13.5%; 28% FM II, 17.6%; specificity: FM I, 96.5%; 2.8% FM II, 99.5%; 14% FM II, 98.8%; 28% FM II, 98.1%. 31/70 patients (44.3%) positive to 28% FM II were negative to FM I, with 14% FM II this proportion being 16/50 (32%). In the group of patients with a certain history, a total of 7 patients were found reacting to FM II only. Conversely, in the group of patients without any fragrance history, there were significantly more positive reactions to FM I than to any concentration of FM II. In conclusion, the new FM II detects additional patients sensitive to fragrances missed by FM I; the number of false-positive reactions is lower with FM II than with FM I. Considering sensitivity, specificity and the frequency of doubtful reactions, the medium concentration, 14% FM II, seems to be the most appropriate diagnostic screening tool.

A total of 2261 (808 male, 1453 female) consecutive patients attending contact dermatitis clinics were patch tested to isoeugenol and its derivatives listed in the EU Inventory of Fragrance Ingredients. Positive reactions were found to isoeugenol in 40, transisoeugenol in 40, isoeugenyl acetate in 19, isoeugenyl benzoate in 4, isoeugenyl phenylacetate in 16, isoeugenyl methyl ether in 6 and benzyl isoeugenyl ether in 2 patients. There was a concomitant reaction to isoeugenol in 36/40 of those positive to transisoeugenol, 13/19 of those to isoeugenyl acetate, 3/4 of those to isoeugenyl benzoate and 15/16 of those to isoeugenyl phenylacetate but in none of those 6 positive to isoeugenyl methyl ether and in neither of those 2 positive to benzyl isoeugenyl ether. Concomitant contact allergy between isoeugenol and its derivatives may occur through chemical cross-reactivity or local skin metabolism of the derivatives. It is more commonly observed with the esters rather than the ethers. Isoeugenyl acetate has been proposed as an alternative to isoeugenol, but there is a high degree of concomitant reactivity with isoeugenol.

Genital ulceration is today often thought to be caused by herpes simplex. In this case report, a rare differential diagnosis, ulcus vulvae acutum is described, probably caused by Epstein-Barr virus (EB-virus).

Background: Contact allergy to grease is rare and often not even suspected. We investigated such a case in which the detected allergen was the stabilizer in the grease, which is rarely found as an allergen., Objective: Thin-layer chromatography (TLC) was used in a novel way and helped detect the allergen., Methods: Patch testing with our standard series, a metal-working series, the different substances individually, the grease in serial dilution and extracts of personal objects, the TLC plate. Gas chromatography-mass spectrometry was also used., Results: Test results indicated contact allergy to grease containing N-phenyl-1-naphthylamine and contact allergy to Disperse Orange 1, N-cyclohexyl-N'-phenyl-4-phenylenediamine, N-isopropyl-N'-phenyl-4-phenylenediamine, and N,N'-diphenyl-4-phenylenediamine., Conclusion: N-phenyl-1-naphthylamine was the main cause of the patient's dermatitis. This case report underlines the importance of testing the patient's own products and also underlines the benefit of using TLC strips for patch testing and of visiting the workplace to get correct information about exposure conditions.

Skin resurfacing with carbon dioxide (CO(2)) laser is a currently popular means of improving rhytides and scars of the face. Side effects are few, but delayed healing has been reported due to infections. A case of unexplained slow healing following CO(2) laser resurfacing in a previously healthy sixty-seven year old woman is reported. Although healing was extremely delayed, it is important to emphasize that a satisfactory cosmetic response was obtained after 16 months.

Oak moss absolute is a long-known, popular natural extract widely used in perfumes. It is reported as the cause of allergic reactions in a significant number of those with perfume allergy. Oak moss absolute has been the target of recent research to identify its allergenic components. Recently, chloroatranol, a hitherto unknown fragrance allergen, was identified in oak moss absolute. The objective was to assess the clinical importance of chloroatranol as a fragrance allergen by characterizing its elicitation profile. 13 patients previously showing a positive patch test to oak moss absolute and chloroatranol were included, together with a control group of 10 patients without sensitization to either of the 2 materials. A serial dilution patch test was performed on the upper back with concentrations ranging from 200 to 0.0063 p.p.m. of chloroatranol in ethanol. Simultaneously, the participant performed an open test simulating the use of perfumes on the volar aspect of the forearms in a randomized and double-blinded design. A solution with 5 p.p.m. chloroatranol was used for 14 days, and, in case of no reaction, the applications were continued for another 14 days with a solution containing 25 p.p.m. All test subjects (13/13) developed an allergic reaction at the site of application of the solution containing chloroatranol. Among them, 12/13 (92%) gave a positive reaction to the 5 p.p.m. solution and 1 to 25 p.p.m. None of the controls reacted (P < 0.001). The use test was terminated at median day 4. The dose eliciting a reaction in 50% of the test subjects at patch testing was 0.2 p.p.m. In conclusion, the hidden exposure to a potent allergen widely used in perfumes has caused a highly sensitized cohort of individuals. Judged from the elicitation profile, chloroatranol is the most potent allergen present in consumer products today.

Citral is a well known contact allergen and a contact irritant. Routine patch testing in the past may have been restricted because of possible irritant (IR) patch test responses. 586 consecutive patients, with hand eczema, were patch tested with a selection of fragrances including citral 2% petrolatum and the European standard series. 28 of the patients showed a positive patch test reaction (+ to +++) to citral and 82 at least 1 IR patch test reaction and no positive patch test reaction to citral. A statistically significant association between a positive patch test reaction to citral and positive patch test reactions to other fragrances compared with IR reactions (n = 82) was established. The difference regarding fragrance history found between those with IR and positive reactions to citral was not significant. Citral could be an allergen and/or irritant, worthy of further more extensive studies.

Recently, we showed that 10 x 2% of consecutively patch-tested hand eczema patients had a positive patch test to a selection of fragrances containing fragrances relevant to hand exposure. In this study, we used repeated skin exposure to a patch test-positive fragrance allergen in patients previously diagnosed with hand eczema to explore whether immersion of fingers in a solution with or without the patch-test-positive fragrance allergen would cause or exacerbate hand eczema on the exposed finger. The study was double blinded and randomized. All participants had a positive patch test to either hydroxycitronellal or Lyral (hydroxyisohexyl 3-cyclohexene carboxaldehyde). Each participant immersed a finger from each hand, once a day, in a solution containing the fragrance allergen or placebo. During the first 2 weeks, the concentration of fragrance allergen in the solution was low (approximately 10 p.p.m.), whilst during the following 2 weeks, the concentration was relatively high (approximately 250 p.p.m.), imitating real-life exposure to a household product like dishwashing liquid diluted in water and the undiluted product, respectively. Evaluation was made using a clinical scale and laser Doppler flow meter. 3 of 15 hand eczema patients developed eczema on the finger immersed in the fragrance-containing solution, 3 of 15 on the placebo finger and 3 of 15 on both fingers. Using this experimental exposure model simulating real-life exposure, we found no association between immersion of a finger in a solution containing fragrance and development of clinically visible eczema on the finger in 15 participants previously diagnosed with hand eczema and with a positive patch test to the fragrance in question.

Fragrance allergy and hand eczema are both common among dermatological patients. Fragrance mix (FM) and its constituents have a recognized relevance to exposure to fine fragrances and cosmetic products. Based on extensive chemical analysis and database search, a new selection of fragrances was established, including 14 known fragrance allergens present in products to which hand exposure would occur. A non-irritating patch-test concentration for some fragrances was established in 212 consecutive patients. 658 consecutive patients presenting with hand eczema were patch tested with the European standard series and the developed selection of fragrances. 67 (10.2%) of the 658 patients had a positive reaction to 1 or more of our selection of fragrance chemicals present in the new selection. The most common reactions to fragrances not included in the FM were to citral, Lyral (hydroxyisohexyl-3-cyclohexene carboxaldehyde) and oxidized l-limonene. A concomitant reaction to the FM identified potential fragrance allergy in less than (1/2) of these patients. Exposure assessment and a statistically significant association between a positive patch test to our selected fragrances and patients' history support the relevance of this selection of fragrances. Those with a positive reaction to our selected fragrances were significantly more likely to have 1 or more positive patch tests in the standard series. This observation is the basis for the hypothesis concerning cross-reactivity and the effect of simultaneous exposure. The study found that fragrance allergy could be a common problem in patients with eczema on the hands.

Hydroxyisohexyl 3-cyclohexene carboxaldehyde, also known as Lyral, is a fragrance ingredient identified as the cause of contact allergic reactions in 2-3% of eczema patients undergoing patch testing. Lyral has been included in the standard patch test series in many clinics due to its importance as an allergen. It has been used without restrictions in cosmetic products, until now. In the present study, the dose-response relationship of Lyral contact allergy was studied with doses relevant for normal exposure in cosmetic products. 18 eczema patients, who previously had given a positive patch test to Lyral 5% petrolatum, were included along with 7 control subjects. All cases were tested with a serial dilution of Lyral in ethanol 6% to 6 p.p.m and subjected to a 2-week, repeated open application test with a low dose of Lyral in ethanol. In the case of no reaction, this was followed by another 2 weeks of testing with a higher dose. The test was performed at the volar aspect of the forearm. In 16 of 18 cases (89%), a positive use test developed, 11 reacting to the low and 5 to the high concentration. None reacted to the vehicle control of ethanol applied to the contralateral arm. All controls were negative to both the test solutions of Lyral and the ethanol control. The difference between the test and the control group was statistically significant (Fisher's test, P < 0.001). It is concluded that Lyral at the current usage levels is inducing sensitization in the community. The same levels were shown to elicit allergic contact dermatitis in almost all sensitized individuals. A significant reduction in usage concentrations is recommended to prevent contact allergic reactions.

Axillary dermatitis is a common problem, particularly in individuals with contact allergy to fragrances. Many individuals suspect their deodorant to be the causal product of their fragrance allergy. It has been shown that deodorants containing cinnamic aldehyde (cinnamal) can elicit axillary dermatitis in patients sensitized to this substance. The aim of the present investigation was to evaluate the importance of hydroxycitronellal used in deodorants for the development of axillary dermatitis, when applied by individuals with and without contact allergy to this fragrance chemical. Patch tests with deodorants and ethanolic solutions containing hydroxycitronellal, as well as repeated open application tests (ROAT) with roll-on deodorants with and without hydroxycitronellal at different concentrations, were performed in 14 dermatitis patients, 7 with and 7 without contact allergy to hydroxycitronellal. A positive ROAT was noted only in the patients hypersensitive to hydroxycitronellal (P < 0.001) and only in the axilla to which the deodorants containing hydroxycitronellal had been applied (P < 0.001). Deodorants containing hydroxycitronellal in the concentration range of 0.032-0.32% used twice daily on healthy skin in individuals hypersensitive to hydroxycitronellal can elicit axillary dermatitis in a few weeks.

Background: A standardised suction technique has been used to sample plasma proteins in dermal interstitial fluid (IF) serially for 5 to 6 days from a suction-induced skin mini-erosion. Increased protein concentrations ascribed to inflammation have been shown from day 1 onward. In this study, we assessed the effect of two different extraction pressures on IF sample composition., Methods: Total protein concentration and the concentrations of insulin, prealbumin, albumin, transferrin, IgG and alpha-2-macroglobulin were assessed daily in healthy volunteers. Samples were extracted at 50 mmHg and 200 mmHg below the atmospheric., Results: At 0 h after forming the erosion, mean total IF protein content (relative to plasma) was lower in the samples extracted at -200 mmHg than at -50 mmHg (26 +/-13% (SD) vs 48 +/-9.8%; p < 0.05). There were no significant differences at 24, 48, 72 or 96 h. Of the individual proteins, expressed as area units (AU) for area under the curve (AUC) from 0-96 h, albumin was lower in IF sampled at -200 mmHg (2.49 +/- 0.68 vs 3.08 +/- 0.36 AU; p < 0.05), as was transferrin (1.91 +/- 0.52 vs 2.40 +/- 0.42 AU; p < 0.05). Extraction volumes were significantly higher at -200 mmHg (AUC diff: 60%; p < 0.05)., Conclusions: Samples of IF extracted at 0 h at -200 mmHg contained lower protein concentrations, indicating an increased water fraction and an intact sieve function of the vascular wall. The difference in protein concentration extracted at higher and lower pressure from 24 h onward was less pronounced. Lower pressure should be used to sample substances of greater molecular size.

Background: A standardised technique using a suction-induced mini-erosion that allows serial sampling of dermal interstitial fluid (IF) for 5 to 6 days has been described. In the present study, we studied permeability changes as a function of time., Methods: We examined IF concentrations of total protein concentration and the concentration of insulin (6.6 kDa), prealbumin (55 kDa), albumin (66 kDa), transferrin (80 kDa), IgG (150 kDa) and alpha-2-macroglobulin (720 kDa) as a function of time, using an extraction pressure of 200 mmHg below atmospheric., Results: At 0 h after forming the erosion, mean total IF protein content (relative to plasma) was 26 +/- 13% (SD). For the individual proteins, the relative mean concentrations were 65 +/- 36% for insulin, 48 +/- 12% for albumin, 30 +/- 19% for transferrin, 31 +/- 15%for IgG and 19.5 +/- 10% for alpha-2-macroglobulin. At 24 h, the total IF protein content was higher than at 0 h (56 +/- 26% vs 26 +/- 13%; p < 0.05, diff: 115%), as were some of the individual protein concentrations: prealbumin (50 +/- 24 vs 25 +/- 13%; p < 0.05), albumin (68 +/- 21 vs 48 +/- 12%; p < 0.05) and IgG (55 +/- 30 vs 31 +/- 15%; p = 0.05). ln the interval 24 h to 96 h the concentrations were relatively unchanged., Conclusions: The results indicate that fluid sampled at 0 h after forming the erosion represents dermal IF before the full onset of inflammation. From 24 h onward, the sampled fluid reflects a steady state of increased permeability induced by inflammation. This technique is promising as a tool for clinically sampling substances that are freely distributed in the body and as a model for studying inflammation and vascular permeability.

The aim of this study was to evaluate a new interstitial fluid (IF) sampling technique and its application in diabetology. IF and venous whole blood were sampled serially during an oral glucose tolerance test (OGTT) on days 1 and 3 after formation of a mini-erosion in eight non-diabetic controls and eight Type 2 diabetic subjects. Glucose, lactate, glycerol, 3-hydroxybutyrate and insulin were assayed in IF and plasma. With solitary exceptions, the IF sample volumes were in excess of those required for measurement of all five substances. However, mean IF sampling rates differed significantly both between the non-diabetic and diabetic groups and between days 1 and 3 (p < 0.001 in all cases). In both groups, the OGTT curves of glucose, glycerol and 3-hydroxybutyrate were similar to the respective curves for plasma, whereas for lactate concentrations they were markedly greater in IF than in plasma (40% and 93% in the control group and 57% and 100% greater in the diabetic group on days 1 and 3, respectively). The reverse was true of insulin concentrations in the non-diabetic group, which were 57% and 74% lower in IF than in plasma on days 1 and 3, respectively. In the non-diabetic group, the baseline (pre-OGTT) insulin level in IF increased from 49 +/- 22% (SD) of that in plasma on day 1 to 74 +/- 19% of that in plasma on day 3 (p=0.005). Sampling site re-epithelialization was rapid. In conclusion, the feasibility of transdermal sampling of IF via a skin mini-erosion has been demonstrated in both diabetic and non-diabetic subjects.

Posture-induced microcirculatory changes in the lower leg were studied in venous leg ulcer patients and in control subjects by means of laser Doppler imaging (LDI), a technique which allows almost real-time mapping of the perfusion from a distance, each perfusion value constituting the mean of a number of measurements at separate sites. LDI values for intact skin with the subject supine were 0.39 (0.32, 0.47) V [geometric mean (gm -SD, gm +SD)] and 0.32 (0.15, 0.70) V in two age groups of controls and 0.91 (0.66, 1.24) V in patients (NS). Values were 2.04 (1.25, 3.35) V for skin at the ulcer margin, and 1.44 (0.72, 2.88) V in the ulcer proper. With the lower leg passively dependent, lower LDI values were obtained at all sites in all groups, the reduction in intact skin value being 62 +/- 11% (arithmetic mean +/- SD) (p < 0.01) in the younger controls, 43 +/- 24% (p < 0.01) in the older controls and 62 +/- 19% (p < 0.001) in the patient group, and the reduction in ulcer values being 45 +/- 27% (p < 0.05) for the margin and 52 +/- 23% (p < 0.001) for the ulcer proper. Thus, a high degree of postural vasoconstriction was present overall, even in the ulcer itself. Vasomotor tone in the skin of the lower leg was assessed by topical application of methyl nicotinate, a vasodilator. The skin perfusion value (supine position, no stimulus) was 71 +/- 31% (p < 0.01) of the drug-induced (assumed peak) hyperaemia value [0.60 (0.30, 1.10) V] in patients and 24 +/- 25% (p < 0.001) of the hyperaemia value (1.30 (0.64, 2.62) V] in the controls. It would appear that in ulcer patients the veno-arteriolar reflex, despite being comparable in magnitude to that in controls, may nonetheless be insufficient to reduce tone during dependency to a level similar to that in healthy controls.

Purpose: To describe a dermally non-invasive serial sampling technique and to test its clinical feasibility with regard to glucose measurement., Methods: A standardized skin mini-erosion devoid of the epidermal barrier, and covered by an artificial one, was formed by a suctioning technique. Interstitial fluid (IF) was extracted serially by brief application of negative pressure, and its glucose content compared with that in capillary or venous blood samples., Results: The procedure caused no discomfort. The epidermis regenerated rapidly after experimentation. There were no complications. In non-diabetic subjects (n = 13) the mean of all IF values measured daily for 6 days was 6.2 +/- 0.1 mmol/l (+/-SE). The corresponding capillary blood glucose value was 5.6 +/- 0.1 mmol/l, and the venous glucose value was 5.4 +/- 0.1 mmol/l. The differences between IF glucose values and invasive control values remained within narrow limits throughout. The 2SD limits of agreement for the differences were 1.44 mmol/l (IF vs. capillary blood samples) and 1.76 mmol/l (IF vs venous samples) respectively. The OGTT curves suggested glucose kinetics to be similar in IF and in capillary blood. In diabetic subjects, the mean of IF values determined serially during one day was 15.3 +/- 1.0 mmol/l (range, 6.7-21.8 mmol/l), and the corresponding mean capillary value was 12.0 +/- 0.9 mmol/l (range, 3.3-17.2 mmol/l). The ICC for all paired photometric observations was 0.948., Conclusions: The results suggest the new sampling technique to be a feasible approach for clinical and experimental purposes. A functionally integrated sampling patch is entering the clinical testing stage.

Laser Doppler imaging (LDI), a new technique which allows measurement of skin blood perfusion at a distance from the skin surface, was assessed methodologically in healthy volunteers. Each skin LDI value was based on virtually real-time measurements obtained from a number of discrete measuring sites. In scans made along the circumference of the lower arm, valid figures for LDI (as distinct from no output at all) were obtained in 8/8 measurements at 0 degrees inclination, and in 16/16 measurements at 7 degrees, 14 degrees, 22 degrees, 30 degrees and 38 degrees, respectively. Beyond this inclination a numerical output was obtained in only 9/16 of measurements at an inclination of 48 degrees, in 7/16 at 69 degrees, and in no more than 1/16 at 90 degrees. Values obtained at angles of inclination greater than 38 degrees fell within the relatively narrow range of values obtained at lesser angles of inclination. The findings are of interest since measuring sites of clinical importance may not be flat. Variability of measurement (coefficient of variation in per cent) was studied in the lower leg by performing LDI and conventional laser Doppler flowmetry (LDF) concomitantly. The coefficient of variation for measurements in one subject at rest was 13% for LDI vs. 19% for LDF, the corresponding interindividual coefficient of variation values being 25% vs. 28%. In response to heating, finger pulp perfusion increased by 55% as measured by LDI (p = 0.0051) and by 44% (p = 0.0756) as measured by LDF. In summary, the findings contribute to the validation of LDI for skin perfusion measurement.

Healthy male volunteers were wounded by skin blistering, excision of the blister roof and u.v.-irradiation of the dermal wound bed. The lesions, painlessly inflicted on one forearm, were occluded, and no systemic therapy was given (n = 7). Ten days later the procedure was repeated contralaterally, and this time hyperbaric oxygen (HBO) therapy was given (1 h at 283 kPa in a 'multi-place' chamber) beginning 1.5 h, 10.5 h and 21.5 h after injury. The maximum 'length' of the lesions - including the surrounding oedema zone - differed throughout the experiment when comparisons were made on a daily basis (P less than 0.005 on day 1). The values were lower after HBO treatment, the difference being maximal on day 1 when it was 41 per cent. The hyperaemia at the periphery of the lesions, assessed with a mechanical laser Doppler linear scanner, was less in the HBO-treated group on days 3, 4, and 5 (P less than 0.05 on day 3). Centrally within the wound the mean Doppler values were lower after HBO-treatment for the duration of the experiment, but the differences were not significant for comparisons made on a daily basis. The exudation rates decreased after HBO treatment (P less than 0.05 on days 2-6). The end-points of epithelialization (5.1 days (HBO group) vs. 5.7 days) did not differ significantly. Thus, HBO had beneficial effects on this superficial dermal lesion. Oedema and exudation decreased, as did the peripheral hyperaemia, but the rate of epithelialization was not accelerated.

Transdermal drug delivery seems a promising way of achieving complete, predictable absorption, but the epidermis is a barrier for most drugs. A new technique for transdermal drug delivery, in which a small patch of epidermis was removed, was tested in seven healthy volunteers by means of the antidiuretic peptide 1-deamino-8-D-arginine vasopressin (DDAVP). The epithelium of a small area of forearm skin (diameter 5 mm) was removed painlessly, and in a standard way, by a simple device operating at a present vacuum. DDAVP was given by way of improvised occlusive reservoirs. Plasma DDAVP concentration/time curves conformed closely with zero-order kinetics, which suggests that the bioavailability approached 100%, corresponding to that for direct intravenous infusion. Four volunteers were given DDAVP daily for 4 days by way of the de-epithelialised site; there were no signs that re-epithelialisation hindered permeation. All plasma DDAVP values substantially exceeded the lowest effective therapeutic concentration for patients with diabetes insipidus. The vacuum removal of the epithelium caused pronounced hyperaemia in the de-epithelialised dermis (assessed by laser doppler flow measurement); the hyperaemia persisted, unaffected by DDAVP, and may have contributed to the efficient permeation. The skin spot appeared normal at 6 weeks.

The effects of exposing blister wounds to u.v. irradiation were assessed in 14 male volunteers, on whose forearms blister wounds (diameter 5 mm, suction set at 200 mmHg below atmospheric for 2 h 15 min, blister roof cut at base), and irradiated blister wounds (as above, in addition u.v. irradiation given selectively for 30 min from a distance of 10 cm), were produced. In non-u.v.-irradiated wounds, flow cessation, assessed by video microscopy (n = 6), was observed in a small proportion of the papillary loop vessels. The oedema adjacent to the wound was poorly developed. Laser Doppler linear scans (n = 8) demonstrated a pronounced hyperaemia in the wound bed and also in the adjacent skin, the reaction subsiding over a few days. The exudation rate, determined by weighing the hydrocolloid dressings applied to the wound, was maximal on day 1 and then rapidly decreased. Epithelialization, assessed evaporimetrically as the time taken for reinstatement of the epidermal water barrier, was complete in 5.1 days. In the u.v.-irradiated wounds the blood flow had ceased in all the papillary loop vessels by day 1, and increased oedema, exudation and hyperaemia at the wound edges were observed. Epithelialization was not significantly retarded by the irradiation injury. After 6 months, slight discolouration of the skin was occasionally observed, but no cosmetically disturbing scars. This benign and standardized wound model in humans--based on a combination of a mechanical suction injury and a superficial radiation burn--may prove to be useful, for instance when studying the effects of burns treatment.

Epithelialization and blood flow in painlessly inflicted small suction blister wounds were studied in healthy volunteers (n = 26) using evaporimetry and laser Doppler flowmetry (LDF), respectively. As expected, the evaporation rate normalized faster in wounds covered by an occlusive film than in wounds covered with gauze. The evaporimetry technique was found to be a simple alternative to the biopsy-based methods that have previously been used in humans. Blood flow was increased after 25 min of suctioning, and the hyperemia increased further after equalization to atmospheric pressure. This wound hyperemia (day 1) was more pronounced than that observed during heating of adjacent skin, and more pronounced at a pressure of 400 mm Hg below atmospheric pressure than at 200 mm Hg below. The hyperemic response lasted for some days and was similar on arm and foot. A mechanical LDF linear scanner was used to create a flow profile across the wound into the adjacent skin. Six months after inflicting the lesions there was no visible scar. The findings suggest that this blister wound model may be useful for studying epithelialization and microcirculatory events after trauma and during early wound healing in humans.