Determination of minimal erythema dose of normal skin to ultraviolet rays / 中华医学美学美容杂志

Objective To investigate the minimal erythema does (MED) of normal skin to UV in Guangzhou city,and to observe its relationship to sex,age,skin type,seasons and the years lived in Guangzhou.Methods 621 healthy subjects were exposed to Solar Simulator (GS2004) and the MED was measured and observed by two professional technicians after (24±2) hours.Results The average MED value of all subjects was (1170.2±333.2) mJ/cm2.In male and female group,the average MED values were (1132.8-339.4) mJ/cm2 and (1182.1 ± 330.7) mJ/cm2,respectively,and there was no significant difference between male and female (P=0.20).The MED value in subjects aged from 30 to 50 (1014.7 ± 359.7) mJ/cm2 was significantly lower than those aged from 20 to 29 (1222.9±304.3) mJ/cm2 and over 50 years (1179.0±374.3) mJ/cm2 (P＜0.01).The MED value in skin type Ⅱ (673.53±228.3) mJ/cm2 was significantly lower than those in type Ⅲ (1224.3±254.2) mJ/cm2 and Ⅳ(1363.1±278.5) mJ/cm2(P＜0.01).There was significant difference of the MED value between different seasons (P＜0.01).The MED value in spring (969.2±355.8) mJ/cm2 was lowest,and followed by summer (969.2± 355.8) mJ/cm2.However,there was no significant difference between autumn and winter (P＞0.05).The MED value in subjects lived in Guangzhou from 5 to 10 years was significantly lower than those whose residence time was from 1 to 4 years and over 10 years,respectively.Conclusions The MED value of the subjects in Guangzhou is quite different from other cities of China,and related to age,skin types,seasons and the years lived in Guangzhou city,while there is no correlation between MED value and gender difference.

Comparative Study of the Gross Interpretation of Phototesting and Objective Measurement with Using a Spectrophotometer for Patients with Psoriasis and Vitiligo Treated with Narrow-band UVB

BACKGROUND:Determination of the minimal erythema dose (MED) is important for developing a phototherapy protocol and to diagnosis photosensitivity disorders. But obtaining a precise and reproducible MED is quite difficult because a phototest for erythema is based on subjective assessment. OBJECTIVE: The objective of our study was to compare the gross interpretation of a phototest and the objective measurement using a spectrophotometer for determining the parameters of cutaneous narrow-band UVB (NBUVB) therapy. METHODS: A total of 14 psoriasis and 10 vitiligo patients who receiving NBUVB phototherapy with skin types III and IV were selected for this study. To perform phototesting, ten sites on the skin of the back were vertically exposed to a series of 10 NBUVB doses among 14 doses between 340 and 1,400 mJ/cm2. We interpreted the gross findings of erythema and measured the L*a*b* values with using a spectrophotometer at each phototest spot and at the control skin. Also, we evaluate the relationship between the gross presentation and the spectrophotometric analysis by delta E for the assessment of the minimal perceptible erythema (MPE) and MED. RESULTS: For all the subjects, the MEDs were measured in the 490~1,000 mJ/cm2 range. The average of the colorimetric values for the control skin were L*: 64.8, a*: 7.9 and b*: 19.8. Among them, the L* value and MED value were shown to be inversely correlated, and as the L* value was decreased, the MED was increased. For the MPE, the delta E, which was the color difference of the normal skin and the phototest area, was within the range of 1.5~3.0 in 17 of the 21 patients, and 4 patients were within the range of 1.0~1.5. For the MED, among the 21 patients, the delta E of 17 patients was within the range of 3.0~6.0, and 4 patients were within the range of 6.0~12.0. CONCLUSION: A spectrophotometer enables UV erythema to be assessed objectively and quantitatively, and this can compensate for the disadvantages of subjective gross interpretation when determining the MED. Delta E is a good novel and objective indicator for determining the MPE and MED. So, a spectrophotometer is a very useful instrument for developing a phototherapy protocol for psoriasis and other dermatoses and for making the diagnosis of photosensitivity disorders.

Comparative Study of the Gross Interpretation of Phototesting and Objective Measurement with Using a Spectrophotometer for Patients with Psoriasis and Vitiligo Treated with Narrow-band UVB

BACKGROUND:Determination of the minimal erythema dose (MED) is important for developing a phototherapy protocol and to diagnosis photosensitivity disorders. But obtaining a precise and reproducible MED is quite difficult because a phototest for erythema is based on subjective assessment. OBJECTIVE: The objective of our study was to compare the gross interpretation of a phototest and the objective measurement using a spectrophotometer for determining the parameters of cutaneous narrow-band UVB (NBUVB) therapy. METHODS: A total of 14 psoriasis and 10 vitiligo patients who receiving NBUVB phototherapy with skin types III and IV were selected for this study. To perform phototesting, ten sites on the skin of the back were vertically exposed to a series of 10 NBUVB doses among 14 doses between 340 and 1,400 mJ/cm2. We interpreted the gross findings of erythema and measured the L*a*b* values with using a spectrophotometer at each phototest spot and at the control skin. Also, we evaluate the relationship between the gross presentation and the spectrophotometric analysis by delta E for the assessment of the minimal perceptible erythema (MPE) and MED. RESULTS: For all the subjects, the MEDs were measured in the 490~1,000 mJ/cm2 range. The average of the colorimetric values for the control skin were L*: 64.8, a*: 7.9 and b*: 19.8. Among them, the L* value and MED value were shown to be inversely correlated, and as the L* value was decreased, the MED was increased. For the MPE, the delta E, which was the color difference of the normal skin and the phototest area, was within the range of 1.5~3.0 in 17 of the 21 patients, and 4 patients were within the range of 1.0~1.5. For the MED, among the 21 patients, the delta E of 17 patients was within the range of 3.0~6.0, and 4 patients were within the range of 6.0~12.0. CONCLUSION: A spectrophotometer enables UV erythema to be assessed objectively and quantitatively, and this can compensate for the disadvantages of subjective gross interpretation when determining the MED. Delta E is a good novel and objective indicator for determining the MPE and MED. So, a spectrophotometer is a very useful instrument for developing a phototherapy protocol for psoriasis and other dermatoses and for making the diagnosis of photosensitivity disorders.

A Comparison of Minimal Erythema Dose and Minimal Melanogenic Dose Induced by Ultraviolet A-1, Broad Band Ultraviolet A, Narrow Band Ultraviolet B, and Broad Band Ultraviolet B / 대한피부과학회지

BACKGROUND: The erythemal and tanning responses of the skin to UV radiations, which are used as diagnostic phototest and guideline of phototherapy, are different, depending on the races and light sources. Minimal erythema dose (MED), barely perceptible minimal melanogenic dose (MMDb) and well-defined border minimal melanogenic dose (minimal melanogenic dose, MMDw) of broad band UVA (BBUVA), UVA-1, broad band UVB (BBUVB), and narrow band UVB (NBUVB) have not yet been reported. Therefore this study was undertaken to measure the MED, MMDb and MMDw of BBUVA, UVA-1, BBUVB and NBUVB radiation. METHODS: Ten healthy Korean volunteers were recruited. Four volnuteers were Fizpatrick skin type III and six were IV. In this study, a metal halide lamp (SUPUVASUN 3000) was used as the BBUVA and UVA-1 light sources, a fluorescent blacklight lamp (Philips TL 20W/12 UVB lamp) as the BBUVB, and a fluorescent blacklight lamp (Philips TL 20W/01) as the NBUVB. The MED, MMDb and MMDw of the skin were visually assessed 24 hours and 7 days after irradiation. RESULTS: 1. BBUVA MED, MMDb and MMDw of BBUVA were 53.0+/-8.2J/cm2 (mean+/-S.D.), 38.0+/-7.8J/cm2, and 51.0+/-8.7J/cm2, respectively. MED, MMDb and MMDw of BBUVA in Fitzpatrick skin phototype III (FST III) were 50.0+/-8.1J/cm2, 35.0+/-5.7J/cm2, and 47.5+/-5.0J/cm2, respectively. MED, MMDb and MMDw of BBUVA in FST IV were 55.0+/-8.3J/cm2, 40.0+/-8.9J/cm2, and 53.3+/-10.3J/cm2, respectively. 2. UVA-1 MED, MMDb and MMDw of BBUVA were 58.0+/-9.1J/cm2, 40.0+/-4.7J/cm2, and 54.0+/-9.6J/cm2, respectively. MED, MMDb and MMDw of BBUVA in FST III were 52.5+/-9.5J/cm2, 37.5+/-5.0J/cm2, and 52.5+/-12.5J/cm2, respectively. MED, MMDb and MMDw of BBUVA in FST IV were 61.6+/-7.5J/cm2, 41.6+/-4.0J/cm2, and 55.0+/-8.3J/cm2, respectively. 3. BBUVB MED, MMDb and MMDw of BBUVA were 52.0+/-12.2mJ/cm2, 57.0+/-10.5mJ/cm2, and 69.0+/-11.0mJ/cm2, respectively. MED, MMDb and MMDw of BBUVA in FST III were 42.5+/-5.0mJ/cm2, 55.0+/-5.7mJ/cm2, and 67.5+/-9.5mJ/cm2, respectively. MED, MMDb and MMDw of BBUVA in FST IV were 58.3+/-11.6mJ/cm2, 58.3+/-13.2mJ/cm2, and 70.0+/-12.6mJ/cm2, respectively. 4. NBUVB MED, MMDb and MMDw of BBUVA were 680+/-131.6mJ/cm2, 770+/-105.9mJ/cm2, and 910+/-99.4mJ/cm2, respectively. MED, MMDb and MMDw of BBUVA in FST III were 650+/-129.1mJ/cm2, 725+/-125.8mJ/cm2, and 850+/-100.0mJ/cm2, respectively. MED, MMDb and MMDw of BBUVA in FST IV were 700+/-141.4mJ/cm2, 800+/-89.4mJ/cm2, and 950+/-83.6mJ/cm2, respectively. CONCLUSION: The MMDb and MMDw induced by BBUVA and UVA-1 were less than MED induced by BBUVA and UVA-1, but MED induced by BBUVB and NBUVB was less than MMDb and MMDw induced by BBUVB and NBUVB. These results suggest that the erythemal and tanning response of the skin to UV radiations are different, depending on the UV wave length.

Minimal Erythema Dose of Narrow Band UVB in Korean Psoriasis Patients / 대한피부과학회지

BACKGROUND: In planning narrow band UVB (NBUVB) phototherapy protocol, assessing a minimal erythema dose (MED) of NBUVB may be essential to gain optimal therapeutic results. However, there are few data regarding to the MED of NBUVB in Koreans and the results are variable according to skin types and photosensors. OBJECTIVE: We assessed MED of NBUVB in psoriasis patients by a photometer designed for NBUVB phototesting, the relationship of skin type and ultraviolet responses. METHODS: Forty psoriasis patients were phototested on their backs with newly developed Waldmann UV meter(R)(Waldmann Co. Germany) for NBUVB phototesting. The MED was investigated by irradiating several NBUVB doses ranging from 200 mJ/cm2 to 1500 mJ/cm2 and then was judged visually 24 hours after. RESULTS: 1.The median and mode value of MED of NBUVB in Korean psoriasis patients were 950 mJ/cm2 (35%). 2. Skin type was well correlated with the MED. CONCLUSION:The MED value of NBUVB in our study may be useful data to set the phototherapy protocol. Skin types are related with MED value and the study is more required to know the exact relationship.

A Comparison of UVB-induced Minimal Erythema Dose ( MED ) s to the Skin of the Back and Extremities in Young Adult Koreans / 대한피부과학회지

BACKGROUND: The erythemal response of the skin to UVB radiation is used as a diagnostic phototest and guideline to phototherapy. OBJECTIVE: The purpose of this study was to compare the UVB-induced MEDs to the back, arm, and thigh skin METHODS: A sunlight fluorescenct lamp(Waldmann UV 7001K) was used as a UVB radiation source. The back, arm, and thigh skin were irradiated with the dose, from 40mJ/cm2 to 180mJ/cm2. The minimal doses for erythema responses to the skin were assessed visually at 24 hours after irradiation. RESULTS: MEDs of the back, arm and thigh skin were 92.6 +/- 17.3mJ/cm2(mean +/- S.D.), 123.0 +/- 24.2mJ/cm2, and 126.6+/- 28.3mJ/cm2, respectively. The most frequent MED was 100mJ/cm2 for the back skin and 120mJ/cm' for the arm skin and thigh skin. CONCLUSION: In this study, UVB-induced MEDs to the back, arm, and thigh skin in young adult Koreans were assessed. A significant difference in the MED was found between the back and extremities skin, with a lower value for the back skin(92.6 +/- 17.3mJ/cm2) than for the arm skin(123.0 +/- 24.2mJ/cm2) or for the thigh skin(126.6 +/- 28.3mJ/cm2).

Relationship between UV-Induced Erythema and Pigmentation Dose-response Angles and The Predictors of Cutaneous Sensitivity to UV Light / 대한피부과학회지

BACKGROUND: There are many predictors of sensitivity to UVR, but controversies exist about their objectivity, correlation between them, and applicability to various races. OBJECTIVE: In 42 healthy volunteers, we assessed the validaty of dose response angle of erythe ma(DRAE) and delayed tanning(DRADT) after UVB irradiation, and also evaluated the correlation hetween dose-response angb s and other predictors of UV sensitivity. METHODS: We measured erythema and melanin index using reflectance spectrophotometer aft,er irradiation of UVB on the back of 42 males. When the erythema index and melanin index were plotted against UV doses for each patient, a dose response curve was obtained. Linear regression analysis was used to calculate the slope of those curves for erythema and delayed tanning, which were called DRAE and DRADl respectively. Also we checked predictots of UV sensitivity such as skin type, MED, MMD, consiitutional and facultative skin color, then analyzed the relation be tween dose response angles and other predictors. RESULTS: Statistically significa it linear regression lines were obtained from 41 subjects regarding to erythema and frorn 31 subjects regarding to delayed tanning. As for the relationship he tween the pvedictors of UV senitivity, only the MED correlated well with DRAE. CONCLUSION: We found that dose response angles, especially DRAE, were an objective and adequate predictor of cutaneous LJV sensitivity, but could not find validity of skin type and skin color in Koreans. A more organized study with a larger number of subjects is needed to clarify the usefulness of the predictors.

Study of the Minimal Erythema Dose and Minimal Melanogenic Dose of UVA - 1 and Minimal Phototoxic Dose of UVA - 1 and UVA - 2 in Young Adult Koreans / 대한피부과학회지

BACKGROUND: Minimal erythema dose(MED), minimal melanogenic dose (MMD) and minimal phototoxic dose(MPD) of UVA-1 in Koreans has not been determined, although MED and MMD of UVB and MPD of UVA-2 in Koreans have been reported. OBJECTIVE: This study was done to measure the MED and MMDs including minimal immediate tanning dose(MITD) and minimal delayed tanning dose(MDTD) of UVA-1 radiation and compare the MPD of UVA-1 with that of UVA-2. METHODS: In this study, a metal halide lamp (SUPUVASUN 3000) and a fluorescent blacklight lamp (Philips TL 20W/09N UVA lamp) were used as the UVA-1 and UVA-2 light sources, respectively. After the determining of Fitzpatrick's skin phototypes, the back skins of young adults were irradiated and the MED, MITD and MDTD of UVA-1 were assessed at 24 hours, 1 hour, and 7 days after irradiation, respectively. The minimal doses of phototoxic reaction, which was induced by oral 8-MOP plus UVA-1 or UVA-2, were assessed visually 72 hours after irradiation. RESULTS: MED,was 61.20+/-11.50J/cm(mean+S.D.). MITD and MDTD of UVA-1 were 48.00+/-8.57J/cm and 65.30+/-12.10J/cm respectively. MPDs of UVA-1 and UVA-2 were 14.88+/-3.88J/cm and 4.40+/-1.69J/cm, respectively. CONCLUSION: In this study, the MED and MMD of UVA-1 radiation and the MPD of UVA-1 and UVA-2 radiation were measured in young adult Koreans. The MITD was less than the MED, and the MDTD was almost the same as the MED. The MPD of UVA-1 was three times higher than that of UVA-2. There vere no significant correlations between the MEDs, MMDs or MPDs and the skin phototypes.

Study of the Minimal Erythema Dose and Minimal Melanogenic Dose of UVA - 1 and Minimal Phototoxic Dose of UVA - 1 and UVA - 2 in Young Adult Koreans / 대한피부과학회지

BACKGROUND: Minimal erythema dose(MED), minimal melanogenic dose (MMD) and minimal phototoxic dose(MPD) of UVA-1 in Koreans has not been determined, although MED and MMD of UVB and MPD of UVA-2 in Koreans have been reported. OBJECTIVE: This study was done to measure the MED and MMDs including minimal immediate tanning dose(MITD) and minimal delayed tanning dose(MDTD) of UVA-1 radiation and compare the MPD of UVA-1 with that of UVA-2. METHODS: In this study, a metal halide lamp (SUPUVASUN 3000) and a fluorescent blacklight lamp (Philips TL 20W/09N UVA lamp) were used as the UVA-1 and UVA-2 light sources, respectively. After the determining of Fitzpatrick's skin phototypes, the back skins of young adults were irradiated and the MED, MITD and MDTD of UVA-1 were assessed at 24 hours, 1 hour, and 7 days after irradiation, respectively. The minimal doses of phototoxic reaction, which was induced by oral 8-MOP plus UVA-1 or UVA-2, were assessed visually 72 hours after irradiation. RESULTS: MED,was 61.20+/-11.50J/cm(mean+S.D.). MITD and MDTD of UVA-1 were 48.00+/-8.57J/cm and 65.30+/-12.10J/cm respectively. MPDs of UVA-1 and UVA-2 were 14.88+/-3.88J/cm and 4.40+/-1.69J/cm, respectively. CONCLUSION: In this study, the MED and MMD of UVA-1 radiation and the MPD of UVA-1 and UVA-2 radiation were measured in young adult Koreans. The MITD was less than the MED, and the MDTD was almost the same as the MED. The MPD of UVA-1 was three times higher than that of UVA-2. There vere no significant correlations between the MEDs, MMDs or MPDs and the skin phototypes.

UVB Induced Minimal Erythema Dose ( MED ) and Minimal Melanogenic Dose ( MMD ) in Young Adult Koreans / 대한피부과학회지

BACKGROUND: The erythemal response and delayed tanning of the skin to UV radiations which are used as diagnostic phototest and guideline of phototherapy are different according to the races and light sources. OBJECTIVE: The MED and MMD induced by UVB radiation were measured in 130 normal young adult Koreans. METHODS: In this study, a high pressure mercury are lamp(Burdick UV-800) and a sunlight fluorescent lamp(Waldmann UV 800) were used as UVB light sources. Multiple sites of the lower baek or buttock skin were irradiated with an increasing dose by a constant, anount. The minimal doses of erythema response and delayed tanning of the skin were assessed visaually at 24 hours and 7 days after irradiation, respectively. RESULTS: MED and MMD of Burdick UV-800 are 18.0+/-9.8mJ/cm2 (mean+/-S.D.), 29.7+/-12.5mJ/cm2, respectively. MED and MMD of Waldmann UV 800 are 70.8+/-28.5mJ/cm2 and 91.2+/-33.1mJ/cm2, respecively. The most frequent MED by Burdick UV-800 is 10mJ/cm2 and those by Waldmann UV 800 are 50m J/cm2 and 60m J/cm2. CONCLUSION: In this study MED and MMD of young adult Koreans by two kinds of UVB light sources were assessed. The RESULTS: how that MED is less than MMD and the levels of MED under which the photosensitivity is suggested are 5.6mJ/cm2 by Burdick UV-800 anr 32.4mJ/cm2 by Waldmann UV 800.

Determination of Minimal Erythema Dose of Normal Skin to Ultraviolet Rays / 中华皮肤科杂志

Objective To determine the normal range of minimal erythema dose (MED) of normal skin to ultraviolet A (UVA) and B (UVB). Methods The definition of MED is the dose of UVA required to induce a just perceptible erythema on an individual′s skin 24 hours after irradiation. One hundred and eighteen subjects including healthy volunteers and patients with noninflammatory skin disorders were enrolled and studied with SUV1000 type UV simulator in March 2002. Results The average MED value for UVA was 55 J/cm2 (range: 18 - 95 J/cm2) in the males, and 40 J/cm2 (range: 15 - 100 J/cm2) in the females. The average MED value for UVB was 31 mJ/cm2 (range: 12 - 95 mJ/cm2) in the males and 29 mJ/cm2 (range: 8 - 95 mJ/cm2) in the females. The MED value for UVA in the males was significantly higher than that in the females (P 0.05). The MED values for UVA as well as UVB in skin type Ⅲ were significantly lower than those in skin type Ⅳ (UVA-MED: P