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Erlandsson, Björn-ErikORCID iD iconorcid.org/0000-0002-1929-135X
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Karbalaie, A., Etehadtavakol, M., Abtahi, F., Fatemi, A., Emrani, Z. & Erlandsson, B.-E. (2018). Image Enhancement Effect on Inter and Intra-observer Reliability of Nailfold Capillary Assessment. Microvascular Research
Öppna denna publikation i ny flik eller fönster >>Image Enhancement Effect on Inter and Intra-observer Reliability of Nailfold Capillary Assessment
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2018 (Engelska)Ingår i: Microvascular Research, ISSN 0026-2862, E-ISSN 1095-9319Artikel i tidskrift (Refereegranskat) 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.

Ort, förlag, år, upplaga, sidor
Elsevier, 2018
Nyckelord
Nailfold capillaroscopy; Image enhancement; Inter and intra-observer reliability; Capillary density; Systemic lupus erythematosus
Nationell ämneskategori
Medicin och hälsovetenskap
Forskningsämne
Medicinsk teknologi
Identifikatorer
urn:nbn:se:miun:diva-37163 (URN)10.1016/j.mvr.2018.06.005 (DOI)000449037600016 ()2-s2.0-85051111896 (Scopus ID)
Anmärkning

QC 20180821

Tillgänglig från: 2018-07-05 Skapad: 2019-09-09Bibliografiskt granskad
Karbalaie, A., Abtahi, F., Fatemi, A., Etehadtavakol, M., Emrani, Z. & Erlandsson, B.-E. (2017). Elliptical broken line method for calculating capillary density in nailfold capillaroscopy: Proposal and evaluation. Microvascular Research, 113, 1-8
Öppna denna publikation i ny flik eller fönster >>Elliptical broken line method for calculating capillary density in nailfold capillaroscopy: Proposal and evaluation
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2017 (Engelska)Ingår i: Microvascular Research, ISSN 0026-2862, E-ISSN 1095-9319, Vol. 113, s. 1-8Artikel i tidskrift (Refereegranskat) 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.

Ort, förlag, år, upplaga, sidor
Academic Press, 2017
Nyckelord
Capillary density, Nailfold capillaroscopy, Number of papillae, Reliability, Repeatability
Nationell ämneskategori
Medicin och hälsovetenskap
Identifikatorer
urn:nbn:se:miun:diva-37162 (URN)10.1016/j.mvr.2017.04.002 (DOI)000404692200001 ()28414021 (PubMedID)2-s2.0-85017510457 (Scopus ID)
Anmärkning

QC 20170619

Tillgänglig från: 2017-06-19 Skapad: 2019-09-09 Senast uppdaterad: 2019-09-20Bibliografiskt granskad
Karbalaie, A., Fatemi, A., Etehadtavakol, M., Abtahi, F., Emrani, Z. & Erlandsson, B.-E. (2016). Counting Capillaries in Nailfold Capillaroscopy:State of the Art and a Proposed Method. In: 2016 IEEE EMBS CONFERENCE ON BIOMEDICAL ENGINEERING AND SCIENCES (IECBES): . Paper presented at Conference on Biomedical Engineering and Sciences (IECBES) (pp. 170-174). IEEE
Öppna denna publikation i ny flik eller fönster >>Counting Capillaries in Nailfold Capillaroscopy:State of the Art and a Proposed Method
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2016 (Engelska)Ingår i: 2016 IEEE EMBS CONFERENCE ON BIOMEDICAL ENGINEERING AND SCIENCES (IECBES), IEEE , 2016, s. 170-174Konferensbidrag, Publicerat paper (Refereegranskat)
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.

Ort, förlag, år, upplaga, sidor
IEEE, 2016
Nationell ämneskategori
Medicin och hälsovetenskap
Forskningsämne
Medicinsk teknologi
Identifikatorer
urn:nbn:se:miun:diva-37164 (URN)10.1109/IECBES.2016.7843437 (DOI)000400605700035 ()2-s2.0-85015704316 (Scopus ID)
Konferens
Conference on Biomedical Engineering and Sciences (IECBES)
Anmärkning

QC 20180327

Tillgänglig från: 2018-03-26 Skapad: 2019-09-09Bibliografiskt granskad
Etehad Tavakol, M., Fatemi, A., Karbalaie, A., Emrani, Z. & Erlandsson, B.-E. (2015). Nailfold Capillaroscopy in Rheumatic Diseases: Which Parameters Should Be Evaluated?. BioMed Research International, 2015, Article ID 974530.
Öppna denna publikation i ny flik eller fönster >>Nailfold Capillaroscopy in Rheumatic Diseases: Which Parameters Should Be Evaluated?
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2015 (Engelska)Ingår i: BioMed Research International, ISSN 2314-6133, E-ISSN 2314-6141, Vol. 2015, artikel-id 974530Artikel i tidskrift (Refereegranskat) 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.

Ort, förlag, år, upplaga, sidor
Hindawi Publishing Corporation, 2015
Nyckelord
Video nailfold capillaroscopy, Rheumatic diseases, Capillary density, Measurement of capillary dimensions
Nationell ämneskategori
Biomedicinsk laboratorievetenskap/teknologi
Forskningsämne
Tillämpad medicinsk teknik
Identifikatorer
urn:nbn:se:miun:diva-37158 (URN)10.1155/2015/974530 (DOI)000361248100001 ()2-s2.0-84941730044 (Scopus ID)
Anmärkning

QC 20150903

Tillgänglig från: 2019-09-09 Skapad: 2019-09-09 Senast uppdaterad: 2019-09-09Bibliografiskt granskad
Karbalaie, A., MONTAZERI, M. M., SHABANI, M. & Erlandsson, B.-E. (2014). Application of Homo-separation of variables method on nonlinearsystem of PDEs. WSEAS Transactions on Mathematics, 13, 992-1000
Öppna denna publikation i ny flik eller fönster >>Application of Homo-separation of variables method on nonlinearsystem of PDEs
2014 (Engelska)Ingår i: WSEAS Transactions on Mathematics, ISSN 1109-2769, E-ISSN 2224-2880, Vol. 13, s. 992-1000Artikel i tidskrift (Refereegranskat) Published
Abstract [en]

In this study, the Homo-Separation of Variables method is introduced to find the exact solution of somecoupled nonlinear partial differential equations. This analytical method is a new combination of two powerfuland popular methods; namely the homotopy perturbation method (HPM) and the separation of variables method.The exact solution is constructed by choosing an appropriate initial approximation in addition to retaining onlythe first term of the series obtained by HPM. The proposed method is capable of reducing the computational loadconsiderably when compared to other classical method.

Ort, förlag, år, upplaga, sidor
World Scientific and Engineering Academy and Society, 2014
Nyckelord
Homo-separation of variables, Homotopy perturbation, Separation of variables, coupled Burgers’ equations
Nationell ämneskategori
Teknik och teknologier
Forskningsämne
Matematik
Identifikatorer
urn:nbn:se:miun:diva-37169 (URN)2-s2.0-84927557680 (Scopus ID)
Anmärkning

QC 20150520

Tillgänglig från: 2019-09-09 Skapad: 2019-09-09 Senast uppdaterad: 2019-09-09Bibliografiskt granskad
Karbalaie, A., Hamid Muhammed, H. & Erlandsson, B.-E. (2013). Using Homo-Separation of Variables for Solving Systems of Nonlinear Fractional Partial Differential Equations. International journal of mathematics and mathematical sciences, 2013, 8
Öppna denna publikation i ny flik eller fönster >>Using Homo-Separation of Variables for Solving Systems of Nonlinear Fractional Partial Differential Equations
2013 (Engelska)Ingår i: International journal of mathematics and mathematical sciences, ISSN 0161-1712, E-ISSN 1687-0425, Vol. 2013, s. 8-Artikel i tidskrift (Refereegranskat) Published
Abstract [en]

A new method proposed and coined by the authors as the homo-separation of variables method is utilized to solve systems oflinear and nonlinear fractional partial differential equations (FPDEs). The new method is a combination of two well-establishedmathematical methods, namely, the homotopy perturbation method (HPM) and the separation of variables method. Whencompared to existing analytical and numerical methods, the method resulting from our approach shows that it is capable ofsimplifying the target problem at hand and reducing the computational load that is required to solve it, considerably.The efficiencyand usefulness of this new general-purposemethod is verified by several examples, where different systems of linear and nonlinearFPDEs are solved.

Ort, förlag, år, upplaga, sidor
Hindawi Publishing Corporation, 2013
Nyckelord
Homo-Separation of Variables
Nationell ämneskategori
Beräkningsmatematik
Forskningsämne
SRA - Informations- och kommunikationsteknik
Identifikatorer
urn:nbn:se:miun:diva-37165 (URN)10.1155/2013/421378 (DOI)2-s2.0-84879317800 (Scopus ID)
Anmärkning

QC 20130710

Tillgänglig från: 2019-09-09 Skapad: 2019-09-09 Senast uppdaterad: 2019-09-09Bibliografiskt granskad
Organisationer
Identifikatorer
ORCID-id: ORCID iD iconorcid.org/0000-0002-1929-135X

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