CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Novel Analysis Toolkit for Capillaroscopic Images: Development and Clinical Evaluation
KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH). KTH.ORCID iD: 0000-0001-7320-2306
2018 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

Nailfold capillaroscopy (NC) is an invasive imaging technique that is used to assess the blood capillary network in the nailfold area. NC is routinely used for patients with microcirculation problems, such as systemic sclerosis and other connective tissue diseases. NC is repeatable and appears to be simple and harmless. However, there is a lack of established guidelines [QCE1] and instructions for both the acquisition and interpretation of the images obtained, which may lead to various ambiguities.

The general aim of this thesis was to reduce the inherent ambiguities in human judgment and diagnosis by introducing novel techniques for assessing the nailfold capillary density, which is an important parameter in NC. To achieve this goal, a toolkit was developed that includes a method to measure the capillary density, an image enhancement technique and a graphical user interface (GUI).

In the first study, a summary of the nailfold videocapillaroscopy procedure was presented, and the common techniques used to evaluate capillaroscopic parameters were reviewed. In the second study, common methods for calculating the capillary density were reviewed, and a survey of the relationship between the number of capillaries as well as the existence of digital ulcers, pulmonary arterial hypertension, autoantibodies, scleroderma patterns and the different scoring systems was performed. In the third study, a novel method was proposed to determine the nailfold capillary density, and this method is referred to as the elliptic broken line (EBL) method. In the fourth study, the EBL method for measuring capillary density was evaluated. In the fifth study, a new image enhancement technique was introduced and evaluated both subjectively and objectively. Finally, clinical applications of the EBL method and enhancement techniques were demonstrated in the sixth study. The result verifies the potential of the proposed EBL method to improve the reliability and repeatability of assessments. Additionally, improving the image quality, i.e., using the proposed enhancement method, can reveal more capillary details for an observer compared to the raw original image, and the results motivate the future development of automatic tools for the EBL method, e.g., automatic segmentation and capillary detection and characterization.

Please note that the font changes here. Please consider using a consistent font type and size throughout the manuscript.

Place, publisher, year, edition, pages
US, AB , 2018. , p. 85
Series
TRITA-CBH-FOU ; 2018:33
Keywords [en]
Nailfold videocapillaroscopy, Image enhancement, Inter and intra-observer reliability
National Category
Medical and Health Sciences
Research subject
Applied Medical Technology
Identifiers
URN: urn:nbn:se:kth:diva-239300ISBN: 978-91-7729-904-2 (print)OAI: oai:DiVA.org:kth-239300DiVA, id: diva2:1264280
Public defence
2018-12-11, Sat T2, Hälsovägen 11, Flemingsberg, 10:00 (English)
Opponent
Supervisors
Note

QC 20181120

Available from: 2018-11-20 Created: 2018-11-19 Last updated: 2018-11-27Bibliographically approved
List of papers
1. Nailfold Capillaroscopy in Rheumatic Diseases: Which Parameters Should Be Evaluated?
Open this publication in new window or tab >>Nailfold Capillaroscopy in Rheumatic Diseases: Which Parameters Should Be Evaluated?
Show others...
2015 (English)In: BioMed Research International, ISSN 2314-6133, E-ISSN 2314-6141, Vol. 2015, article id 974530Article in journal (Refereed) [Artistic work] Published
Abstract [en]

Video nailfold capillaroscopy (NFC), considered as an extension of the widefield technique, allows a more accurate measuring andstoring of capillary data and a better defining, analyzing, and quantifying of capillary abnormalities. Capillaroscopic study is oftenperformed on the patients suspected of having microcirculation problems such as Raynaud’s phenomenon as the main indicationfor nailfold capillaroscopy. Capillaroscopic findings based on microcirculation studies can provide useful information in the fieldsof pathophysiology, differential diagnosis, and monitoring therapy. Nailfold capillaroscopy provides a vital assessment in clinicalpractices and research; for example, its reputation in the early diagnosis of systemic sclerosis is well established and it is also usedas a classification criterion in this regard. This review focuses on the manner of performing video nailfold capillaroscopy and on acommon approach for measuring capillary dimensions in fingers and toes.

Place, publisher, year, edition, pages
Hindawi Publishing Corporation, 2015
Keywords
Video nailfold capillaroscopy, Rheumatic diseases, Capillary density, Measurement of capillary dimensions
National Category
Biomedical Laboratory Science/Technology
Research subject
Applied Medical Technology
Identifiers
urn:nbn:se:kth:diva-172920 (URN)10.1155/2015/974530 (DOI)000361248100001 ()2-s2.0-84941730044 (Scopus ID)
Note

QC 20150903

Available from: 2015-09-01 Created: 2015-09-01 Last updated: 2018-11-20Bibliographically approved
2. Capillary density: An important parameter in nailfold capillaroscopy
Open this publication in new window or tab >>Capillary density: An important parameter in nailfold capillaroscopy
Show others...
2017 (English)In: Microvascular Research, ISSN 0026-2862, E-ISSN 1095-9319, Vol. 109, p. 7-18Article in journal (Refereed) Published
Abstract [en]

Nailfold capillaroscopy is one of the various noninvasive bioengineering methods used to investigate skin microcirculation. It is an effective examination for assessing microvascular changes in the peripheral circulation; hence it has a significant role for the diagnosis of Systemic sclerosis with the classic changes of giant capillaries as well as the decline in capillary density with capillary dropout. The decline in capillary density is one of microangiopathic features existing in connective tissue disease. It is detectable with nailfold capillaroscopy. This parameter is assessed by applying quantitative measurement. In this article, we reviewed a common method for calculating the capillary density and the relation between the number of capillaries as well as the existence of digital ulcers, pulmonary arterial hypertension, autoantibodies, scleroderma patterns and different scoring system.

Place, publisher, year, edition, pages
Netherland: Elsevier, 2017
Keywords
Nailfold capillaroscopy, Capillary density, Antinuclear antibodies, Digital ulcer, Pulmonary arterial hypertension
National Category
Medical and Health Sciences
Research subject
Medical Technology
Identifiers
urn:nbn:se:kth:diva-193699 (URN)10.1016/j.mvr.2016.09.001 (DOI)000390614200002 ()27614146 (PubMedID)2-s2.0-84988851167 (Scopus ID)
Note

QC 20161017

Available from: 2016-10-09 Created: 2016-10-09 Last updated: 2018-11-20Bibliographically approved
3. Counting Capillaries in Nailfold Capillaroscopy:State of the Art and a Proposed Method
Open this publication in new window or tab >>Counting Capillaries in Nailfold Capillaroscopy:State of the Art and a Proposed Method
Show others...
2016 (English)In: 2016 IEEE EMBS CONFERENCE ON BIOMEDICAL ENGINEERING AND SCIENCES (IECBES), IEEE, 2016, , p. 5p. 170-174Conference paper, Published paper (Refereed)
Abstract [en]

Capillaries play a crucial role in the microcirculatory system by exchanging metabolic substrates and waste products between blood and various tissues. The behavior of capillaries is affiliated with the number of capillaries per unit volume of tissue. Among the various noninvasive techniques available for analyzing skin microcirculation, nailfold capillaroscopyis considered to be a simple and easy-to-perform technique that allows a direct in-vivo visualization of the capillary network.Capillary density is one of the most important parameters in the studies involving capillaroscopy images. Capillary density in most of studies is defined as the number of capillaries in a one-millimeter span of the distal row in each finger or toe. This definition is silent about counting or excluding the number of the capillary with different shapes. However, there is no single standard for counting the number of capillaries in a span of one millimeter. In this paper, a novel method is proposed for determining the nailfold capillary density. This method is a modified combination of two existing techniques: the direct observation and the 90◦ method.Compared to the two existing approaches, the proposed method is more straightforward and easy to use for cases in which the capillaries have different shapes and sizes. Through different examples, we have shown how this method can be used to select the apex point of the capillary and subsequently count the number of capillaries with several papillae.

Place, publisher, year, edition, pages
IEEE, 2016. p. 5
National Category
Medical and Health Sciences
Research subject
Medical Technology
Identifiers
urn:nbn:se:kth:diva-224836 (URN)10.1109/IECBES.2016.7843437 (DOI)000400605700035 ()2-s2.0-85015704316 (Scopus ID)
Conference
Conference on Biomedical Engineering and Sciences (IECBES)
Note

QC 20180327

Available from: 2018-03-26 Created: 2018-03-26 Last updated: 2018-11-20Bibliographically approved
4. Elliptical broken line method for calculating capillary density in nailfold capillaroscopy: Proposal and evaluation
Open this publication in new window or tab >>Elliptical broken line method for calculating capillary density in nailfold capillaroscopy: Proposal and evaluation
Show others...
2017 (English)In: Microvascular Research, ISSN 0026-2862, E-ISSN 1095-9319, Vol. 113, p. 1-8Article in journal (Refereed) Published
Abstract [en]

Nailfold capillaroscopy is a practical method for identifying and obtaining morphological changes in capillaries which might reveal relevant information about diseases and health. Capillaroscopy is harmless, and seems simple and repeatable. However, there is lack of established guidelines and instructions for acquisition as well as the interpretation of the obtained images; which might lead to various ambiguities. In addition, assessment and interpretation of the acquired images are very subjective. In an attempt to overcome some of these problems, in this study a new modified technique for assessment of nailfold capillary density is introduced. The new method is named elliptic broken line (EBL) which is an extension of the two previously known methods by defining clear criteria for finding the apex of capillaries in different scenarios by using a fitted elliptic. A graphical user interface (GUI) is developed for pre-processing, manual assessment of capillary apexes and automatic correction of selected apexes based on 90° rule. Intra- and inter-observer reliability of EBL and corrected EBL is evaluated in this study. Four independent observers familiar with capillaroscopy performed the assessment for 200 nailfold videocapillaroscopy images, form healthy subject and systemic lupus erythematosus patients, in two different sessions. The results show elevation from moderate (ICC = 0.691) and good (ICC = 0.753) agreements to good (ICC = 0.750) and good (ICC = 0.801) for intra- and inter-observer reliability after automatic correction of EBL. This clearly shows the potential of this method to improve the reliability and repeatability of assessment which motivates us for further development of automatic tool for EBL method.

Place, publisher, year, edition, pages
Academic Press, 2017
Keywords
Capillary density, Nailfold capillaroscopy, Number of papillae, Reliability, Repeatability
National Category
Medical and Health Sciences
Identifiers
urn:nbn:se:kth:diva-207279 (URN)10.1016/j.mvr.2017.04.002 (DOI)000404692200001 ()28414021 (PubMedID)2-s2.0-85017510457 (Scopus ID)
Note

QC 20170619

Available from: 2017-06-19 Created: 2017-06-19 Last updated: 2018-11-20Bibliographically approved
5. Image Enhancement Effect on Inter and Intra-observer Reliability of Nailfold Capillary Assessment
Open this publication in new window or tab >>Image Enhancement Effect on Inter and Intra-observer Reliability of Nailfold Capillary Assessment
Show others...
2018 (English)In: Microvascular Research, ISSN 0026-2862, E-ISSN 1095-9319Article in journal (Refereed) Published
Abstract [en]

Background: Nailfold capillaroscopy (NC) is a diagnostic imaging technique that is used to assess the blood capillary network in the nailfold area. NC is routinely used for patients with microcirculation problems, such as systemic sclerosis and other connective tissue diseases.  Experts commonly use subjective evaluation as a reference point in images of nailfold video capillaroscopy, so it is important to reduce the inherent ambiguities in human judgment and diagnosis. Image quality is an important factor that affects measurement error and assessment time of NC images.

Objective: In this study, a new image enhancement technique was introduced and evaluated subjectively.

Methods: In total, 475 nailfold video capillaroscopy images from 18 healthy subjects and 41 systemic lupus erythematosus patients were used. The images were randomly divided into two sets, one each with 275 and 200. Eight independent observers who were familiar with the capillaroscopy technique participated in this study. The set of 275 images was evaluated by three observers with the forced–choice pairwise comparison method. Elliptic broken line (EBL) was used to count the number of capillaries. The intra- and inter-observer reliability of the original and enhanced images was evaluated on 200 images by five observers.

Result: Except for eight images, all observers preferred the enhanced images in the visual quality comparison method. The intra-class correlation coefficient (ICC) of intra- and inter-observer reliability increased from 0.76-0.84 to 0.82-0.89, respectively, when using the enhancement method.

Conclusion: By improving the image quality, more capillary details will be visible, and an observer can document more details that may not be visible in the original image and can do so more efficiently.

Place, publisher, year, edition, pages
Elsevier, 2018
Keywords
Nailfold capillaroscopy; Image enhancement; Inter and intra-observer reliability; Capillary density; Systemic lupus erythematosus
National Category
Medical and Health Sciences
Research subject
Medical Technology
Identifiers
urn:nbn:se:kth:diva-231959 (URN)10.1016/j.mvr.2018.06.005 (DOI)000449037600016 ()2-s2.0-85051111896 (Scopus ID)
Note

QC 20180821

Available from: 2018-07-05 Created: 2018-07-05 Last updated: 2018-11-20Bibliographically approved
6. Nailfold microvascular changes in patients with systemic lupus erythematosus and their predictors
Open this publication in new window or tab >>Nailfold microvascular changes in patients with systemic lupus erythematosus and their predictors
Show others...
(English)Manuscript (preprint) (Other academic)
Keywords
Nailfold video capillaroscopy; Systemic lupus erythematosus, Microcirculation
National Category
Medical and Health Sciences
Research subject
Applied Medical Technology
Identifiers
urn:nbn:se:kth:diva-239297 (URN)
Note

QC 20181120

Available from: 2018-11-19 Created: 2018-11-19 Last updated: 2018-11-20Bibliographically approved

Open Access in DiVA

fulltext(20263 kB)8 downloads
File information
File name FULLTEXT03.pdfFile size 20263 kBChecksum SHA-512
159b3766909e3ae92b6b28621ed56cbeede497e0130671ef20f944140d61f3bc47eb3b97195ccf350bef75285e6c558481cec8d59fc97f0889dfe921def4fb0f
Type fulltextMimetype application/pdf

Search in DiVA

By author/editor
Karbalaie, Abdolamir
By organisation
School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH)
Medical and Health Sciences

Search outside of DiVA

GoogleGoogle Scholar
Total: 24 downloads
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

isbn
urn-nbn

Altmetric score

isbn
urn-nbn
Total: 680 hits
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf