Imaging of laser-excited Imaging of laser-excited skin autofluorescence skin autofluorescence

bleaching rates.bleaching rates.

Kristine Rozniece, Ilona HartmaneKristine Rozniece, Ilona HartmaneClinical Center of Skin and ST Diseases, Riga, LatviaClinical Center of Skin and ST Diseases, Riga, LatviaJanis Lesinsh, Janis Spigulis, ASI, LU, Riga, LatviaJanis Lesinsh, Janis Spigulis, ASI, LU, Riga, Latvia

European Social FundEuropean Social Fund

"Biophotonic research group""Biophotonic research group"Nr.2009/0211/1DP/1.1.1.2.0/09/APIA/VIAA/077Nr.2009/0211/1DP/1.1.1.2.0/09/APIA/VIAA/077

BADV,Riga, 08.09.2011.BADV,Riga, 08.09.2011.

Autofluorescence of SkinAutofluorescence of Skin An optical diagnostic technique An optical diagnostic technique in vivoin vivo that that

differentiates skin lesions from healthy tissuedifferentiates skin lesions from healthy tissue,, based on measurements of the fluorescence based on measurements of the fluorescence intensityintensity emitted by native fluorophores present emitted by native fluorophores present in different concentration in skin tissues.in different concentration in skin tissues.

This autofluorescence is due to the absorption of This autofluorescence is due to the absorption of the exciting radiation by fluorophores the exciting radiation by fluorophores (tryptophan, collagen, elastin, NADH, flavin, (tryptophan, collagen, elastin, NADH, flavin, lipofuscin, melanin, hemoglobin) that resultlipofuscin, melanin, hemoglobin) that resultss in in emission of radiation at higher wavelenghts.emission of radiation at higher wavelenghts.

Autofluorescence PhotobleachingAutofluorescence Photobleaching

The process of decreasing the The process of decreasing the fluoroscence intensity during long-term fluoroscence intensity during long-term optical excitation.optical excitation.

Is caused by degradation of the skin Is caused by degradation of the skin endogenous fluorophore molecules.endogenous fluorophore molecules.

The florophores that emit under blue-The florophores that emit under blue-green excitation are NAD, kreatin, as well green excitation are NAD, kreatin, as well as the dermal collagen and elastin.as the dermal collagen and elastin.

AimAim of Research of Research

In this study In this study there there are presented some are presented some comparative results of using green light comparative results of using green light (532 nm), low power cw laser as excitation (532 nm), low power cw laser as excitation source for cutaneous autofluorescence source for cutaneous autofluorescence investigations and evaluation of investigations and evaluation of autofluorescence properties of normal skin autofluorescence properties of normal skin and different skin pathalogies and different skin pathalogies in vivoin vivo..

Materials and Materials and MMethodsethods

The round spot The round spot of of 4 mm in diameter w4 mm in diameter wasas selected on skin of the inner forearm of selected on skin of the inner forearm of healthy volunteer, and the spot whealthy volunteer, and the spot wasas irradiated by 532 nm cw low power laser irradiated by 532 nm cw low power laser for 1 min. (n= 30)for 1 min. (n= 30)

PatienPatientts with benign different melanocytic, s with benign different melanocytic, vascular, hyperkeratotic and fibrotic vascular, hyperkeratotic and fibrotic lesions of skin (n=74)lesions of skin (n=74)

Patients with BCC (n=2)Patients with BCC (n=2)

Junctional NMNJunctional NMN

Compound NMNCompound NMN

AngiomaAngioma

Seborrheic keratosisSeborrheic keratosis

DermatofibromaDermatofibroma

BCCBCC

gersed3 - AF intensistāte pie 600nm (532nm lāzera ierosme)

0

500

1000

1500

2000

2500

3000

3500

4000

4500

0 5 10 15 20 25 30 35 40 45 50

Laiks (sekundes)

AF

in

ten

sitā

te (

rel.

v.)

garsed2 - AF intensistāte pie 600nm (532nm lāzera ierosme)

0

50

100

150

200

250

300

350

400

450

500

0 10 20 30 40 50 60

Laiks (sekundes)

AF

in

ten

sitā

te (

rel.

v.)

AF in different skin pathologiesAF in different skin pathologies

0 30 60 90

0,0

0,5

1,0

AF

Inte

nsi

ty (

no

rma

lize

d b

y m

ax)

Time (Seconds)

BCC lentigo compound NMN angioma blue nevus% junctional NMN

Distribution of patientsDistribution of patients

BCC

dermatofibroma

seborrheic keratosis

angioma

lentigo

congenital nevus

dysplastic nevus

blue NMN

compound NMN

junctional NMN

Statistical Statistical AAnalysisnalysis

According the Shapiro –Wilk test min, According the Shapiro –Wilk test min, max, and average intensity of AF was max, and average intensity of AF was not normally distributed in all patient not normally distributed in all patient groups.groups.

DDueue t this reasonhis reason we used we used the the Mann – Mann – Withney test for further analysis of Withney test for further analysis of differences.differences.

Ave

rage

inte

nsity

of A

F

6000

5000

4000

3000

2000

1000

0

BCCderm

atofibroma

seborrheic keratosis

angioma

lentigo

congenital nevus

dysplastic nevus

blue NMN

compound NM

N

junctional NMN

De

cre

ase

of

AF

inte

nsi

ty in

30

s

3000

2000

1000

0

ConclusionConclusionss

Taking in consideration that various shapes of Taking in consideration that various shapes of autofluorescence in cases of different skin autofluorescence in cases of different skin pathologies were clearly different, wpathologies were clearly different, we e have have foundfound statistically significant differences in min, statistically significant differences in min, max and average only max and average only betweenbetween groups with groups with junctional and compound NMN.junctional and compound NMN.

BCC showBCC showss the highest AF intensity the highest AF intensity in in comperasion comperasion with other pathologies, but more with other pathologies, but more patients should be involvedpatients should be involved to get to get statistically statistically significant resultssignificant results in this study. in this study.

Thank you for your Thank you for your attention!attention!