Publication detail
Automatic Evaluation of Collagen Fiber Directions from Polarized Light Microscopy Images
NOVÁK, K. POLZER, S. TICHÝ,M. BURŠA, J.
Czech title
Automatické vyhodnocování směrů kolageních vláken ze snímků polarizované mikroskopie
English title
Automatic Evaluation of Collagen Fiber Directions from Polarized Light Microscopy Images
Type
journal article in Web of Science
Language
en
Original abstract
Mechanical properties of the arterial wall depend largely on orientation and density of collagen fiber bundles. Several methods have been developed for observation of collagen orientation and density; the most frequently applied collagen-specific manual approach is based on polarized light (PL). However, it is very time consuming and the results are operator dependent. We have proposed a new automated method for evaluation of collagen fiber direction from two-dimensional polarized light microscopy images (2D PLM). The algorithm has been verified against artificial images and validated against manual measurements. Finally the collagen content has been estimated. The proposed algorithm was capable of estimating orientation of some 35 k points in 15 min when applied to aortic tissue and over 500 k points in 35 min for Achilles tendon. The average angular disagreement between each operator and the algorithm was -9.3±8.6° and -3.8±8.6° in the case of aortic tissue and -1.6±6.4° and 2.6±7.8° for Achilles tendon. Estimated mean collagen content was 30.3±5.8% and 94.3±2.7% for aortic media and Achilles tendon, respectively. The proposed automated approach is operator independent and several orders faster than manual measurements and therefore has the potential to replace manual measurements of collagen orientation via PLM.
Czech abstract
Mechanické vlastnosti stěny tepny závisí podstatně na orientaci a hustotě kolageních vláken. Bylo vyvinuto několik metod pro pozorování orientace a hustoty kolagenu; nejužívanější je manuální metoda, která je založena na polarizovaném světle a je specifická pouze pro kolagen. Nicméně je časově velmi náročná a výslekdy jsou závislé na operátorovi. My jsme vyvinuli novou automatickou metodu na zjištování směrů kolageních vláken z dvou rozměrných polarizovaných snímů. Algoritmus byl verifikován pomocí umělých snímků a validován pomocí manuálního měření. Obsah kolagenu byl taktéž vyhodnocen. Navrhnutý algoritmus je schopen vyhodnotit orientaci u cca 35 tis bodů za 15 minut u snímků ze stěny cévy a více než 500tis bodů za 35 minut u achilovek. Průměrná úhlová odchylka mezi každým operátorem a algoritmem bylo 9.3±8.6° a -3.8±8.6° v případě aorty a -1.6±6.4° and 2.6±7.8° pro Achivovku. Obsah kolagenu byl 30.3±5.8% pro aortu a 94.3±2.7% pro Achilovku. Navrhnutý automatický přístup je nezávislý na operátori a je o několik řádů rychlejší než manuální měření a tedy má potenciál nahradit manuální měření orientací kolageních vláken pomocí polarizované mikroskopie.
English abstract
Mechanical properties of the arterial wall depend largely on orientation and density of collagen fiber bundles. Several methods have been developed for observation of collagen orientation and density; the most frequently applied collagen-specific manual approach is based on polarized light (PL). However, it is very time consuming and the results are operator dependent. We have proposed a new automated method for evaluation of collagen fiber direction from two-dimensional polarized light microscopy images (2D PLM). The algorithm has been verified against artificial images and validated against manual measurements. Finally the collagen content has been estimated. The proposed algorithm was capable of estimating orientation of some 35 k points in 15 min when applied to aortic tissue and over 500 k points in 35 min for Achilles tendon. The average angular disagreement between each operator and the algorithm was -9.3±8.6° and -3.8±8.6° in the case of aortic tissue and -1.6±6.4° and 2.6±7.8° for Achilles tendon. Estimated mean collagen content was 30.3±5.8% and 94.3±2.7% for aortic media and Achilles tendon, respectively. The proposed automated approach is operator independent and several orders faster than manual measurements and therefore has the potential to replace manual measurements of collagen orientation via PLM.
Keywords in English
collagen fiber orientation; image analysis; phase correlation; polarized light microscopy
RIV year
2015
Released
08.05.2015
Publisher
Cambridge Journals
Location
USA
ISSN
1431-9276
Volume
21
Number
4
Pages from–to
863–875
Pages count
13
BIBTEX
@article{BUT114756,
author="Kamil {Novák} and Stanislav {Polzer} and Jiří {Burša} and Michal {Tichý},
title="Automatic Evaluation of Collagen Fiber Directions from Polarized Light Microscopy Images",
year="2015",
volume="21",
number="4",
month="May",
pages="863--875",
publisher="Cambridge Journals",
address="USA",
issn="1431-9276"
}