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Kindberg, Katarina
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Kindberg, K., Haraldsson, H., Sigfridsson, A., Engvall, J., Ingels, N. B., Ebbers, T. & Karlsson, M. (2012). Myocardial strains from 3D displacement encoded magnetic resonance imaging. BMC Medical Imaging, 12(9)
Öppna denna publikation i ny flik eller fönster >>Myocardial strains from 3D displacement encoded magnetic resonance imaging
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2012 (Engelska)Ingår i: BMC Medical Imaging, ISSN 1471-2342, E-ISSN 1471-2342, Vol. 12, nr 9Artikel i tidskrift (Refereegranskat) Published
Abstract [en]

Background

The ability to measure and quantify myocardial motion and deformation provides a useful tool to assist in the diagnosis, prognosis and management of heart disease. The recent development of magnetic resonance imaging methods, such as harmonic phase analysis of tagging and displacement encoding with stimulated echoes (DENSE), make detailed non-invasive 3D kinematic analyses of human myocardium possible in the clinic and for research purposes. A robust analysis method is required, however.

Methods

We propose to estimate strain using a polynomial function which produces local models of the displacement field obtained with DENSE. Given a specific polynomial order, the model is obtained as the least squares fit of the acquired displacement field. These local models are subsequently used to produce estimates of the full strain tensor.

Results

The proposed method is evaluated on a numerical phantom as well as in vivo on a healthy human heart. The evaluation showed that the proposed method produced accurate results and showed low sensitivity to noise in the numerical phantom. The method was also demonstrated in vivo by assessment of the full strain tensor and to resolve transmural strain variations.

Conclusions

Strain estimation within a 3D myocardial volume based on polynomial functions yields accurate and robust results when validated on an analytical model. The polynomial field is capable of resolving the measured material positions from the in vivo data, and the obtained in vivo strains values agree with previously reported myocardial strains in normal human hearts.

Ort, förlag, år, upplaga, sidor
BioMed Central, 2012
Nationell ämneskategori
Annan medicinteknik
Identifikatorer
urn:nbn:se:liu:diva-90358 (URN)10.1186/1471-2342-12-9 (DOI)000321344800001 ()
Tillgänglig från: 2013-03-25 Skapad: 2013-03-25 Senast uppdaterad: 2017-12-06
Kindberg, K., Haraldsson, H., Sigfridsson, A., Sakuma, H., Ebbers, T. & Karlsson, M. (2012). Temporal 3D Lagrangian strain from 2D slice followed cine DENSE MRI. Clinical Physiology and Functional Imaging, 32(2), 139-144
Öppna denna publikation i ny flik eller fönster >>Temporal 3D Lagrangian strain from 2D slice followed cine DENSE MRI
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2012 (Engelska)Ingår i: Clinical Physiology and Functional Imaging, ISSN 1475-0961, E-ISSN 1475-097X, Vol. 32, nr 2, s. 139-144Artikel i tidskrift (Refereegranskat) Published
Abstract [en]

A quantitative analysis of myocardial mechanics is fundamental to the understanding of cardiac function, diagnosis of heart disease and assessment of therapeutic intervention. In the clinical situation, where limited scan time often is important, a detailed analysis of the myocardium in a specific region might be more applicable than a full 3D measurement of the entire left ventricle. This paper presents a method to obtain temporal evolutions of transmural 3D Lagrangian strains from two intersecting 2D planes of slice followed cine displacement encoding with stimulated echoes (DENSE) data using a bilinear-cubic polynomial element to resolve strain from the displaced myocardial positions. The method demonstrates accurate results when validated in an analytical model, and has been applied to in vivo data acquired on a 3 T magnetic resonance (MR) system from a healthy volunteer to quantify systolic strains at the anterior-basal region of left ventricular myocardium. The in vivo results agree within experimental accuracy with values reported in the literature.

Ort, förlag, år, upplaga, sidor
Wiley-Blackwell, 2012
Nyckelord
Myocardium; kinematics; magnetic resonance; transmural
Nationell ämneskategori
Teknik och teknologier
Identifikatorer
urn:nbn:se:liu:diva-60200 (URN)10.1111/j.1475-097X.2011.01068.x (DOI)000299734400010 ()
Tillgänglig från: 2010-10-07 Skapad: 2010-10-07 Senast uppdaterad: 2017-12-12
Kindberg, K. (2010). Invasive and Non-Invasive Quantification of Cardiac Kinematics. (Doctoral dissertation). Linköping: Linköping University Electronic Press
Öppna denna publikation i ny flik eller fönster >>Invasive and Non-Invasive Quantification of Cardiac Kinematics
2010 (Engelska)Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
Abstract [en]

The ability to measure and quantify myocardial motion and deformation provides a useful tool to assist in the diagnosis, prognosis and management of heart disease. Myocardial motion can be measured by means of several different types of data acquisition. The earliest myocardial motion tracking technique was invasive, based on implanting radiopaque markers into the myocardium around the left ventricle, and recording the marker positions during the cardiac cycle by biplane cineradiography. Until recently, this was the only method with high enough spatial resolution of three-dimensional (3D) myocardial displacements to resolve transmural behaviors. However, the recent development of magnetic resonance imaging techniques, such as displacement encoding with stimulated echoes (DENSE), make detailed non-invasive 3D transmural kinematic analyses of human myocardium possible in the clinic and for research purposes.

Diastolic left ventricular filling is a highly dynamic process with early and late transmitral inflows and it is determined by a complex sequence of many interrelated events and parameters. Extensive research has been performed to describe myocardial kinematics during the systolic phase of the cardiac cycle, but not by far the same amount of research has been accomplished during diastole. Measures of global and regional left ventricular kinematics during diastole are important when attempting to understand left ventricular filling characteristics in health and disease.

This thesis presents methods for invasive and non-invasive quantification of cardiac kinematics, with focus on diastole. The project started by quantification of changes in global left ventricular kinematics during diastolic filling. The helical myocardial fiber architecture of the left ventricle produces both long- and short-axis motion as well as torsional deformation. The longitudinal excursion of the mitral annular plane is an important component of left ventricular filling and ejection. This was studied by analyzing the contribution of mitral annular dynamics to left ventricular filling volume in the ovine heart.

In order to quantify strains for a specific body undergoing deformation, displacements for a set of internal points at a deformed configuration relative to a reference configuration are needed. A new method for strain quantification from measured myocardial displacements is presented in this thesis. The method is accurate and robust and delivers analytical expressions of the strain components. The developed strain quantification method is simple in nature which aids to bridge a possible gap in understanding between different disciplines and is well suited for sparse arrays of displacement data.

Analyses of myocardial kinematics at the level of myocardial fibers require knowledge of cardiac tissue architecture. Temporal changes in myofiber directions during the cardiac cycle have been analyzed in the ovine heart by combining histological measurements of transmural myocardial architecture and local transmural strains.

Rapid early diastolic filling is an essential component of the left ventricular function. Such filling requires a highly compliant chamber immediately after systole, allowing inflow at low driving pressures. Failure of this process can lead to exercise intolerance and ultimately to heart failure. A thorough analysis of the relation between global left ventricular kinematics and local myocardial strain at the level of myocardial fibers during early diastole in the ovine heart was performed by applying the method for strain quantification and the technique for computing temporal changes in myocardial architecture on measures of myocardial displacements and tissue architecture in the ovine heart.

As data acquisition technologies develop, quantification methods for cardiac kinematics need to be adapted and validated on the new types of data. Recent improvements of DENSE magnetic resonance imaging enable non-invasive transmural strain analyses in the human heart. The strain quantification method was first tailored to displacement data from a surgically implanted bead array but has been extended to applications on non-invasive DENSE data measured in two and three dimensions. Validation against an analytical standard reveals accurate results and in vivo strains agree with values for normal human hearts from other studies.

The method has in this thesis been used with displacement data from invasive marker technology and non-invasive DENSE magnetic resonance imaging, but can equally well be applied on any type of displacement data provided that the spatial resolution is high enough to resolve local strain variations.

Ort, förlag, år, upplaga, sidor
Linköping: Linköping University Electronic Press, 2010. s. 49
Serie
Linköping Studies in Science and Technology. Dissertations, ISSN 0345-7524 ; 1322
Nationell ämneskategori
Teknik och teknologier
Identifikatorer
urn:nbn:se:liu:diva-60202 (URN)978-91-7393-375-9 (ISBN)
Disputation
2010-08-17, sal C3, Hus C, Campus Valla, Linköpings universitet, Linköping, 10:15
Opponent
Handledare
Tillgänglig från: 2010-10-07 Skapad: 2010-10-07 Senast uppdaterad: 2016-03-14Bibliografiskt granskad
Kindberg, K., Oom, C., Ingels, N. B. & Karlsson, M. (2010). Strain based estimation of time dependent transmural myocardial architecture in the ovine heart. Biomechanics and Modeling in Mechanobiology, 10(4), 521-528
Öppna denna publikation i ny flik eller fönster >>Strain based estimation of time dependent transmural myocardial architecture in the ovine heart
2010 (Engelska)Ingår i: Biomechanics and Modeling in Mechanobiology, ISSN 1617-7959, E-ISSN 1617-7940, Vol. 10, nr 4, s. 521-528Artikel i tidskrift (Refereegranskat) Published
Abstract [en]

Left ventricular myofibers are connected by an extensive extracellular collagen matrix to form myolaminar sheets. Histological cardiac tissue studies have previously observed a pleated transmural distribution of sheets in the ovine heart, alternating sign of the sheet angle from epicardium to endocardium. The present study investigated temporal variations in myocardial fiber and sheet architecture during the cardiac cycle. End diastolic histological measurements made at subepicardium, midwall and subendocardium at an anterior-basal and a lateral-equatorial region of the ovine heart, combined with transmural myocardial Lagrangian strains, showed that the sheet angle but not the fiber angle varied temporally throughout the cardiac cycle. The magnitude of the sheet angle decreased during systole at all transmural depths at the anterior-basal site and at midwall and subendocardium depths at the lateral-equatorial site, making the sheets more parallel to the radial axis. These results support a previously suggested accordion-like wall thickening mechanism of the myocardial sheets.

Ort, förlag, år, upplaga, sidor
SpringerLink, 2010
Nyckelord
Cardiac mechanics; transmural; sheets; wall thickening; myocardium
Nationell ämneskategori
Teknik och teknologier
Identifikatorer
urn:nbn:se:liu:diva-60199 (URN)10.1007/s10237-010-0252-4 (DOI)20821245 (PubMedID)
Tillgänglig från: 2010-10-07 Skapad: 2010-10-07 Senast uppdaterad: 2017-12-12Bibliografiskt granskad
Kindberg, K., Carlhäll, C., Karlsson, M., Nguyen, T. C., Cheng, A., Langer, F., . . . Jr Ingels, N. B. (2009). Transmural Strains in the Ovine Left Ventricular Lateral Wall During Diastolic Filling. JOURNAL OF BIOMECHANICAL ENGINEERING-TRANSACTIONS OF THE ASME, 131(6)
Öppna denna publikation i ny flik eller fönster >>Transmural Strains in the Ovine Left Ventricular Lateral Wall During Diastolic Filling
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2009 (Engelska)Ingår i: JOURNAL OF BIOMECHANICAL ENGINEERING-TRANSACTIONS OF THE ASME, ISSN 0148-0731, Vol. 131, nr 6Artikel i tidskrift (Refereegranskat) Published
Abstract [en]

Rapid early diastolic left ventricular (LV) filling requires a highly compliant chamber immediately after systole, allowing inflow at low driving pressures. The transmural LV deformations associated with such filling are not completely understood. We sought to characterize regional transmural LV strains during diastole, with focus on early filling, in ovine hearts at 1 week and 8 weeks after myocardial marker implantation. In seven normal sheep hearts, 13 radiopaque markers were inserted to silhouette the LV chamber and a transmural beadset was implanted into the lateral equatorial LV wall to measure transmural strains. Four-dimensional marker dynamics were obtained 1 week and 8 weeks thereafter with biplane videofluoroscopy in closed-chest, anesthetized animals. LV transmural strains in both cardiac and fiber-sheet coordinates were studied from filling onset to the end of early filling (EOEF, 100 ms after filling onset) and at end diastole. At the 8 week study, subepicardial circumferential strain (E-CC) had reached its final value already at EOEF, while longitudinal and radial strains were nearly zero at this time. Subepicardial E-CC and fiber relengthening (E-ff) at EOEF were reduced to 1 compared with 8 weeks after surgery (E-CC:0.02 +/- 0.01 to 0.08 +/- 0.02 and E-ff:0.00 +/- 0.01 to 0.03 +/- 0.01, respectively, both P < 0.05). Subepicardial E-CC during early LV filling was associated primarily with fiber-normal and sheet-normal shears at the 1 week study, but to all three fiber-sheet shears and fiber relengthening at the 8 week study. These changes in LV subepicardial mechanics provide a possible mechanistic basis for regional myocardial lusitropic function, and may add to our understanding of LV myocardial diastolic dysfunction.

Nyckelord
biomechanics, biomedical measurement, cardiology, diagnostic radiography, medical disorders, strain measurement
Nationell ämneskategori
Medicin och hälsovetenskap
Identifikatorer
urn:nbn:se:liu:diva-18556 (URN)10.1115/1.3118774 (DOI)
Tillgänglig från: 2009-06-01 Skapad: 2009-06-01 Senast uppdaterad: 2016-03-14
Carlhäll, C., Kindberg, K., Wigström, L., Daughters, G. T., Millers, D. C., Karlsson, M. & Ingels Jr, N. B. (2007). Contribution of mitral annular dynamics to LV diastolic filling with alteration in preload and inotropic state. American Journal of Physiology. Heart and Circulatory Physiology, 293(3), G1473-H1479
Öppna denna publikation i ny flik eller fönster >>Contribution of mitral annular dynamics to LV diastolic filling with alteration in preload and inotropic state
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2007 (Engelska)Ingår i: American Journal of Physiology. Heart and Circulatory Physiology, ISSN 0363-6135, E-ISSN 1522-1539, Vol. 293, nr 3, s. G1473-H1479Artikel i tidskrift (Refereegranskat) Published
Abstract [en]

Mitral annular (MA) excursion during diastole encompasses a volume that is part of total left ventricular (LV) filling volume (LVFV). Altered excursion or area variation of the MA due to changes in preload or inotropic state could affect LV filling. We hypothesized that changes in LV preload and inotropic state would not alter the contribution of MA dynamics to LVFV. Six sheep underwent marker implantation in the LV wall and around the MA. After 7–10 days, biplane fluoroscopy was used to obtain three-dimensional marker dynamics from sedated, closed-chest animals during control conditions, inotropic augmentation with calcium (Ca), preload reduction with nitroprusside (N), and vena caval occlusion (VCO). The contribution of MA dynamics to total LVFV was assessed using volume estimates based on multiple tetrahedra defined by the three-dimensional marker positions. Neither the absolute nor the relative contribution of MA dynamics to LVFV changed with Ca or N, although MA area decreased (Ca, P < 0.01; and N, P < 0.05) and excursion increased (Ca, P < 0.01). During VCO, the absolute contribution of MA dynamics to LVFV decreased (P < 0.001), based on a reduction in both area (P < 0.001) and excursion (P < 0.01), but the relative contribution to LVFV increased from 18 ± 4 to 45 ± 13% (P < 0.001). Thus MA dynamics contribute substantially to LV diastolic filling. Although MA excursion and mean area change with moderate preload reduction and inotropic augmentation, the contribution of MA dynamics to total LVFV is constant with sizeable magnitude. With marked preload reduction (VCO), the contribution of MA dynamics to LVFV becomes even more important.

Nationell ämneskategori
Teknik och teknologier
Identifikatorer
urn:nbn:se:liu:diva-41883 (URN)10.1152/ajpheart.00208.2007 (DOI)59289 (Lokalt ID)59289 (Arkivnummer)59289 (OAI)
Tillgänglig från: 2009-10-10 Skapad: 2009-10-10 Senast uppdaterad: 2017-12-13
Kindberg, K., Karlsson, M., Ingels, N. J. & Criscione, J. (2007). Nonhomogeneous strain from sparse marker arrays for analysis of transmural myocardial mechanics. Journal of Biomechanical Engineering, 129(4), 603-610
Öppna denna publikation i ny flik eller fönster >>Nonhomogeneous strain from sparse marker arrays for analysis of transmural myocardial mechanics
2007 (Engelska)Ingår i: Journal of Biomechanical Engineering, ISSN 0148-0731, E-ISSN 1528-8951, Vol. 129, nr 4, s. 603-610Artikel i tidskrift (Refereegranskat) Published
Abstract [en]

Background: Knowledge of normal cardiac kinematics is important when attempting to understand the mechanisms that impair the contractile function of the heart during disease. The complex kinematics of the heart can be studied by inserting radiopaque markers in the cardiac wall and study the pumping heart with biplane cineradiography. In order to study the local strain, the bead array was developed where small radiopaque beads are inserted along three columns transmurally in the left ventricle. Method: This paper suggests a straightforward method for strain computation, based on polynomial least-squares fitting and tailored for combined marker and bead array analyses. Results: This polynomial method gives small errors for a realistic bead array on an analytical test case. The method delivers an explicit expression of the Lagrangian strain tensor as a polynomial function of the coordinates of material points in the reference configuration. The method suggested in this paper is validated with analytical strains on a deforming cylinder resembling the heart, compared to a previously suggested finite element method, and applied to in vivo ovine data. The errors in the estimated strain components are shown to remain unchanged on an analytical test case when evaluating the effects of one missing bead. In conclusion, the proposed strain computation method is accurate and robust, with errors smaller or comparable to the current gold standard when applied on an analytical test case.

Nationell ämneskategori
Teknik och teknologier
Identifikatorer
urn:nbn:se:liu:diva-41891 (URN)10.1115/1.2746385 (DOI)000248737000016 ()59323 (Lokalt ID)59323 (Arkivnummer)59323 (OAI)
Tillgänglig från: 2009-10-10 Skapad: 2009-10-10 Senast uppdaterad: 2017-12-13
Kindberg, K. (2006). Applied statistics: Analysing myocardial strain tensors at two times and at three wall depths. Linköping: Linköpings universitet
Öppna denna publikation i ny flik eller fönster >>Applied statistics: Analysing myocardial strain tensors at two times and at three wall depths
2006 (Engelska)Rapport (Övrigt vetenskapligt)
Ort, förlag, år, upplaga, sidor
Linköping: Linköpings universitet, 2006
Serie
LiU-IMT-IS ; 70
Nationell ämneskategori
Medicin och hälsovetenskap
Identifikatorer
urn:nbn:se:liu:diva-35147 (URN)25147 (Lokalt ID)25147 (Arkivnummer)25147 (OAI)
Tillgänglig från: 2009-10-10 Skapad: 2009-10-10
Oom, C., Kindberg, K. & Karlsson, M. (2006). Cardiac Kinematics - Mapping of variations in laminar fiber and sheet architecture during the cardiac cycle. Linköping: Linköpings universitet
Öppna denna publikation i ny flik eller fönster >>Cardiac Kinematics - Mapping of variations in laminar fiber and sheet architecture during the cardiac cycle
2006 (Engelska)Rapport (Övrigt vetenskapligt)
Ort, förlag, år, upplaga, sidor
Linköping: Linköpings universitet, 2006
Serie
LiU-IMT-R ; 46
Nationell ämneskategori
Medicin och hälsovetenskap
Identifikatorer
urn:nbn:se:liu:diva-35146 (URN)25146 (Lokalt ID)91-85643-90-4 (ISBN)25146 (Arkivnummer)25146 (OAI)
Tillgänglig från: 2009-10-10 Skapad: 2009-10-10 Senast uppdaterad: 2016-03-14
Kindberg, K., Oom, C. & Karlsson, M. (2006). Cardiac Kinematics - The coupling between local strain and global left ventricular volume. Linköping: Linköpings universitet
Öppna denna publikation i ny flik eller fönster >>Cardiac Kinematics - The coupling between local strain and global left ventricular volume
2006 (Engelska)Rapport (Övrigt vetenskapligt)
Ort, förlag, år, upplaga, sidor
Linköping: Linköpings universitet, 2006
Serie
LiU-IMT-R ; 45
Nationell ämneskategori
Medicin och hälsovetenskap
Identifikatorer
urn:nbn:se:liu:diva-35145 (URN)25145 (Lokalt ID)91-85299-48-0 (ISBN)25145 (Arkivnummer)25145 (OAI)
Tillgänglig från: 2009-10-10 Skapad: 2009-10-10 Senast uppdaterad: 2016-03-14
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