Assessment of Skin Scars in Clinical Practice and Scientific Studies

119 Pages·2011·2.72 MB·English

ILKKA KAARTINEN
Assessment of Skin Scars in
Clinical Practice and Scientific Studies
Introducing Spectrocutometry,
a new objective method
ACADEMIC DISSERTATION
To be presented, with the permission of
the board of the School of Medicine of the University of Tampere,
for public discussion in the Small Auditorium of Building M,
Pirkanmaa Hospital District, Teiskontie 35,
Tampere, on December 2nd, 2011, at 12 o’clock.
UNIVERSITY OF TAMPERE
ACADEMIC DISSERTATION
University of Tampere, School of Medicine
Tampere University Hospital, Department of Plastic Surgery, Musculoskeletal Surgery
and Rehabilitation
Finland
Supervised by Reviewed by
Docent Hannu Kuokkanen Docent Virve Koljonen
University of Tampere University of Helsinki
Finland Finland
Docent Patrik Lassus
University of Helsinki
Finland
Distribution Tel. [phone]
Bookshop TAJU Fax [phone]
P.O. Box 617 [email protected]
33014 University of Tampere www.uta.fi/taju
Finland http://granum.uta.fi
Cover design by
Mikko Reinikka
Acta Universitatis Tamperensis 1671 Acta Electronica Universitatis Tamperensis 1135
ISBN 978-951-44-8608-1 (print) ISBN 978-951-44-8609-8 (pdf)
ISSN-L 1455-1616 ISSN 1456-954X
ISSN 1455-1616 http://acta.uta.fi
Tampereen Yliopistopaino Oy – Juvenes Print
Tampere 2011
To my family
When you can measure what you are speaking about,
and express it in numbers, you know something about
it; but when you cannot measure it, when you cannot
express it in numbers, your knowledge is of a meagre
and unsatisfactory kind: it may be the beginning of
knowledge, but you have scarcely, in your thoughts,
advanced to the stage of science.
Sir William Thomson (Lord Kelvin),
Popular Lectures and Addresses 1891–1894
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Table of Contents
Abbreviations...................................................................................................8
List of original communications......................................................................10
1. Abstract.....................................................................................................12
2. Tiivistelmä.................................................................................................15
3. Introduction...............................................................................................18
4. Review of the literature..............................................................................21
4.1 Normal wound healing........................................................................21
4.2 Healing and treatment of the split-thickness skin graft donor
site......................................................................................................22
4.3 Scarless foetal healing.........................................................................22
4.4 Hypertrophic and keloid scarring.........................................................23
4.4.1 Clinical features of pathologic scars..........................................23
4.4.2 The process of scar formation....................................................25
4.4.3 Histopathological features of hypertrophic scars and
keloids 25
4.4.4 Genetics of keloid scarring........................................................28
4.4.5 Incidence and risk factors of hypertrophic scars and
keloids 28
4.5 Requirements of scar assessment methods...........................................32
4.6 Current methods for scar assessment...................................................34
4.6.1 Subjective assessment...............................................................34
4.6.1.1 Vancouver burn scar assessment scale...........................34
4.6.1.2 The Patient and Observer Scar Assessment Scale..........35
4.6.1.3 The Manchester scar scale.............................................35
4.6.1.4 Visual analogue scales..................................................36
4.6.1.5 Other subjective scar assessment scales.........................36
4.6.2 Current objective methods.........................................................40
4.6.2.1 Spectrophotometers.......................................................40
4.6.2.2 Tonometric and suction devices....................................41
4.6.2.3 Ultrasonography............................................................43
4.6.2.4 Three-dimensional imaging...........................................44
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4.6.2.5 Laser Doppler flowmetry...............................................44
4.6.2.6 Confocal microscopy.....................................................45
4.7 Skin imaging with reflectance spectrophotometry................................46
4.7.1 Colour chromophores of the skin...............................................46
4.7.2 Principles of reflectance spectrophotometry in skin
colour measurement...................................................................47
4.8 Digital imaging of skin disorders.........................................................48
4.8.1 Colour measurement from digital images...................................49
4.8.2 Digital imaging of chronic wounds............................................49
4.8.3 Digital planimetry......................................................................50
5. Aims of the study.......................................................................................51
6. Subjects and methods.................................................................................52
6.1 Patients and volunteers (Studies I–IV).................................................52
6.2 Methods...............................................................................................53
6.2.1 Skin graft donor site assessment (Study I)..................................53
6.2.2 Colour measurement in the Allen's test (Study II)......................53
6.2.3 Standardized digital imaging used in Spectrocutometry
(Studies III and IV)....................................................................54
6.2.4 Subjective and objective scar assessment (Studies I, III
and IV) 55
6.2.5 Image segmentation and spectral modelling (Studies III
and IV) 56
6.2.6 Statistical analysis (Studies I–IV)..............................................58
7. Results .......................................................................................................59
7.1 Outcome of the skin graft donor site healing comparing
Suprathel® and Mepilex Transfer® dressings (Study I).......................59
7.2 Estimation of skin haemoglobin concentration comparing the
results of Allen's test and Monte Carlo simulation (Study II)...............61
7.3 Donor site scar assessment with Spectrocutometry and
subjective rating scales (Study III).......................................................63
7.4 Reliability and concurrent validity of subjective assessment and
Spectrocutometry in scar assessment (Studies III and IV)....................66
8. Discussion..................................................................................................71
8.1 Treatment of the split-thickness skin graft donor sites..........................71
8.2 Spectrocutometry in measuring the concentrations of melanin
and haemoglobin in skin scars.............................................................73
8.3 The reliability and validity of subjective scar assessment with
VSS and POSAS.................................................................................74
6
8.4 Objective methods in scar assessment..................................................76
9. Conclusions...............................................................................................79
10. Future perspectives...................................................................................80
11. Acknowledgements...................................................................................81
12. References................................................................................................83
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Abbreviations
ARD Automatic relevancy detection
BVD Blood vessel density
CCLS Computer controlled lighting system
CI Confidence interval
DTM Dermal torque meter
ECC Estimated concentration change
EGF Epidermal growth factor
EAI Equal appearing interval
Hb Haemoglobin
ICC Intraclass correlation coefficient
IL-1 Interleukin 1
RS Reflectance spectrophotometry
LED Light emitting diode
LSCM Laser scanning confocal microscopy
MSS Manchester scar scale
MTG Mepilex Transfer® Group
PDGF Platelet derived growth factor
POSAS Patient and Observer Scar Assessment Scale
RCM Reflectance confocal microscopy
SDI Standardized digital imaging
SG Suprathel® group
SGDS Split-thickness skin graft donor site
SIAscopy Spectrophotometric intracutaneous analysis
SpM Spectral modelling
STSG Split thickness skin graft
TGFB Transforming growth factor (cid:533)
US Ultrasonography
UV Ultraviolet
VSS Vancouver Burn Scar Scale
VAS Visual analogue scale
8
VEGF Vascular endothelial growth factor
9
List of original communications
The present study is based on the following articles, which have been referred to
in the text by their Roman numerals (I-IV)
I. Kaartinen IS, Kuokkanen H. Suprathel causes less bleeding and scarring than
Mepilex Transfer in the treatment of donor sites of split thickness skin grafts.
J Plast Surg Hand Surg. In press.
II. Välisuo P, Kaartinen I, Kuokkanen H, Alander J. The colour of blood in skin:
a comparison of Allen’s test and photonics simulations. Skin Res Technol. 2010
Nov;16(4):390-6.*
III. Kaartinen I, Välisuo P, Alander J, Kuokkanen H. Objective scar assessment –a
new method using standardized digital imaging and spectral modelling. Burns. 2011
Feb;37(1):74-81.
IV. Kaartinen I, Välisuo P, Botchko V, Alander J, Kuokkanen H. How to assess
scar hypertrophy? A comparison of subjective scales and Spectrocutometry: a new
objective method. Wound Repair and Regeneration. 2011, 19(3): 316-23.*
The original publications are reproduced with permission of the copyright
owners.
* These articles are also included in the dissertation of MSc Petri Välisuo in the
University of Vaasa.
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