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Vigueras Guillén, J.P. (author), van Rooij, J.G.J. (author), van Dooren, Bart T.H. (author), Lemij, Hans G. (author), Islamaj, Esma (author), van Vliet, L.J. (author), Vermeer, K.A. (author)Corneal guttae, which are the abnormal growth of extracellular matrix in the corneal endothelium, are observed in specular images as black droplets that occlude the endothelial cells. To estimate the corneal parameters (endothelial cell density [ECD], coefficient of variation [CV], and hexagonality [HEX]), we propose a new deep learning...journal article 2022
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Ghafaryasl, B. (author), VERMEER, KOENRAAD A. (author), Kalkman, J. (author), Dore-Callewaert, T.W.J. (author), DE BOER, JOHANNES F. (author), van Vliet, L.J. (author)Optical properties, such as the attenuation coefficients of multi-layer tissue samples, could be used as a biomarker for diagnosis and disease progression in clinical practice. In this paper, we present a method to estimate the attenuation coefficients in a multi-layer sample by fitting a single scattering model for the OCT signal to the...journal article 2021
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van Valenberg, W. (author), Klein, S. (author), Vos, F.M. (author), Koolstra, Kirsten (author), van Vliet, L.J. (author), Poot, D.H.J. (author)Quantitative MRI methods that estimate multiple physical parameters simultaneously often require the fitting of a computational complex signal model defined through the Bloch equations. Repeated Bloch simulations can be avoided by matching the measured signal with a precomputed signal dictionary on a discrete parameter grid (i.e. lookup table...journal article 2020
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Vigueras Guillén, J.P. (author), van Rooij, Jeroen (author), Engel, Angela (author), Lemij, Hans G. (author), van Vliet, L.J. (author), Vermeer, K.A. (author)Purpose: To present a fully automatic method to estimate the corneal endothelium parameters from specular microscopy images and to use it to study a one-year follow-up after ultrathin Descemet stripping automated endothelial keratoplasty. Methods: We analyzed 383 post ultrathin Descemet stripping automated endothelial keratoplasty images from...journal article 2020
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Ghafaryasl, B. (author), Vermeer, Koenraad A. (author), Kalkman, J. (author), Dore-Callewaert, T.W.J. (author), Boer, Johannes F.D.E. (author), van Vliet, L.J. (author)The attenuation coefficient (AC) is an optical property of tissue that can be estimated from optical coherence tomography (OCT) data. In this paper, we aim to estimate the AC accurately by compensating for the shape of the focused beam. For this, we propose a method to estimate the axial PSF model parameters and AC by fitting a model for an...journal article 2020
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Vigueras Guillén, J.P. (author), Sari, B. (author), Goes, S.F. (author), Lemij, Hans G. (author), van Rooij, Jeroen (author), Vermeer, K.A. (author), van Vliet, L.J. (author)Background<br/><br/>Corneal endothelium (CE) images provide valuable clinical information regarding the health state of the cornea. Computation of the clinical morphometric parameters requires the segmentation of endothelial cell images. Current techniques to image the endothelium in vivo deliver low quality images, which makes automatic...journal article 2019
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Arkesteijn, G.A.M. (author), Poot, D.H.J. (author), Ikram, M.A. (author), Niessen, W.J. (author), van Vliet, L.J. (author), Vernooij, M.W. (author), Vos, F.M. (author)The goal of this paper is to increase the statistical power of crossing-fiber statistics in voxelwise analyses of diffusion-weighted magnetic resonance imaging (DW-MRI) data. In the proposed framework, a fiber orientation atlas and a model complexity atlas were used to fit the ball-and-sticks model to diffusion-weighted images of subjects in...journal article 2019
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Vigueras Guillén, J.P. (author), van Rooij, Jeroen G.J. (author), Lemij, Hans G. (author), Vermeer, K.A. (author), van Vliet, L.J. (author)The morphometric parameters of the corneal endothelium – cell density (ECD), cell size variation (CV), and hexagonality (HEX) – provide clinically relevant information about the cornea. To estimate these parameters, the endothelium is commonly imaged with a non-contact specular microscope and cell segmentation is performed to these images. In...conference paper 2019
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Vigueras Guillén, J.P. (author), Lemij, Hans G. (author), Van Rooij, Jeroen (author), Vermeer, K.A. (author), van Vliet, L.J. (author)In images of the corneal endothelium (CE) acquired by specular microscopy, endothelial cells are commonly only visible in a part of the image due to varying contrast, mainly caused by challenging imaging conditions as a result of a strongly curved endothelium. In order to estimate the morphometric parameters of the corneal endothelium, the...conference paper 2019
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Rassam, F. (author), Zhang, T. (author), Cieslak, K. P. (author), Lavini, C. (author), Stoker, J. (author), Bennink, R. J. (author), van Gulik, T. M. (author), van Vliet, L.J. (author), Runge, J. H. (author), Vos, F.M. (author)Objectives: To compare Gd-EOB-DTPA dynamic hepatocyte-specific contrast-enhanced MRI (DHCE-MRI) with <sup>99m</sup> Tc-mebrofenin hepatobiliary scintigraphy (HBS) as quantitative liver function tests for the preoperative assessment of patients undergoing liver resection. Methods: Patients undergoing liver surgery and preoperative assessment...journal article 2019
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Zhang, T. (author), Runge, Jurgen H. (author), Lavini, Cristina (author), Stoker, Jaap (author), van Gulik, Thomas (author), Cieslak, Kasia P. (author), van Vliet, L.J. (author), Vos, F.M. (author)Purpose Pharmacokinetic models facilitate assessment of properties of the micro-vascularization based on DCE-MRI data. However, accurate pharmacokinetic modeling in the liver is challenging since it has two vascular inputs and it is subject to large deformation and displacement due to respiration. Methods We propose an improved...journal article 2019
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van Schie, J.J.N. (author), Lavini, Cristina (author), van Vliet, L.J. (author), Kramer, Gem (author), Pieters - van den Bos, Indra (author), Marcus, H.J.J. (author), Stoker, Jaap (author), Vos, F.M. (author)Background: Pharmacokinetic (PK) models can describe microvascular density and integrity. An essential component of PK models is the arterial input function (AIF) representing the time-dependent concentration of contrast agent (CA) in the blood plasma supplied to a tissue. Purpose/Hypothesis: To evaluate a novel method for subject-specific...journal article 2018
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Trull, A.K. (author), van der Horst, J. (author), van Vliet, L.J. (author), Kalkman, J. (author)We present a comparison of image reconstruction techniques for optical projection tomography. We compare conventional filtered back projection, sinogram filtering using the frequency–distance relationship (FDR), image deconvolution, and 2D point-spread-function-based iterative reconstruction. The latter three methods aim to remove the spatial...journal article 2018
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Filatova, O.G. (author), van Vliet, L.J. (author), Schouten, A.C. (author), Kwakkel, Gert (author), van der Helm, F.C.T. (author), Vos, F.M. (author)Better insight into white matter (WM) alterations after stroke onset could help to understand the underlying recovery mechanisms and improve future interventions. MR diffusion imaging enables to assess such changes. Our goal was to investigate the relation of WM diffusion characteristics derived from diffusion models of increasing complexity...journal article 2018
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Puylaert, Carl A.J. (author), Schüffler, Peter J. (author), Naziroglu, R.E. (author), Tielbeek, Jeroen A.W. (author), Li, Z. (author), Makanyanga, Jesica C. (author), Tutein Nolthenius, Charlotte J. (author), Nio, C. Yung (author), Pendsé, Douglas A. (author), Menys, Alex (author), Ponsioen, Cyriel Y. (author), Atkinson, David (author), Forbes, Alastair (author), Buhmann, Joachim M. (author), Fuchs, Thomas J. (author), Hatzakis, Haralambos (author), van Vliet, L.J. (author), Stoker, Jaap (author), Taylor, Stuart A. (author), Vos, F.M. (author)Rationale and Objectives: The objective of this study was to develop and validate a predictive magnetic resonance imaging (MRI) activity score for ileocolonic Crohn disease activity based on both subjective and semiautomatic MRI features. Materials and Methods: An MRI activity score (the “virtual gastrointestinal tract [VIGOR]” score) was...journal article 2018
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Vigueras Guillén, J.P. (author), Andrinopoulou, Eleni Rosalina (author), Engel, Angela (author), Lemij, Hans G. (author), van Rooij, J. (author), Vermeer, K.A. (author), van Vliet, L.J. (author)Corneal endothelium images obtained by in vivo specular microscopy provide important information to assess the health status of the cornea. Estimation of clinical parameters, such as cell density, polymegethism, and pleomorphism, requires accurate cell segmentation. State-of-the-art techniques to automatically segment the endothelium are...journal article 2018
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Zhang, T. (author), Wu, Z. (author), Runge, Jurgen H. (author), Lavini, Cristina (author), Stoker, Jaap (author), Van Gulik, Thomas (author), Cieslak, Kasia P. (author), van Vliet, L.J. (author), Vos, F.M. (author)The Couinaud classification of hepatic anatomy partitions the liver into eight functionally independent segments. Detection and segmentation of the hepatic vein (HV), portal vein (PV) and inferior vena cava (IVC) plays an important role in the subsequent delineation of the liver segments. To facilitate pharmacokinetic modeling of the liver...conference paper 2018
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Ghafaryasl, B. (author), Vermeer, K.A. (author), Kalkman, J. (author), Dore-Callewaert, T.W.J. (author), de Boer, J.F. (author), van Vliet, L.J. (author)The attenuation coefficient (AC) is a property related to the microstructure of tissue on a wavelength scale that can be estimated from optical coherence tomography (OCT) data. Since the OCT signal sensitivity is affected by the finite spectrometer/detector resolution called roll-off and the shape of the focused beam in the sample arm,...conference paper 2018
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Li, Z. (author), van Vliet, L.J. (author), Stoker, Jaap (author), Vos, F.M. (author)Purpose: To develop a method for intra-patient registration of pre- and post-contrast abdominal MR images with large local deformations and large intensity variations. Method: A hybrid method is proposed to deal with this problem. It consists of two coupled techniques: (1) descriptor matching (DM) at the original resolution using a discrete...journal article 2018
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van der Graaff, L. (author), Boyaval, Fanny (author), van Vliet, L.J. (author), Stallinga, S. (author)In the field of pathology there is an ongoing transition to the use of Whole Slide Imaging (WSI) systems which scan tissue slides at intermediate resolution (0∼.25 μm) and high throughput (15mm<sup>2</sup>=min) to digital image files. Most scanners currently on the market are line-sensor based push-broom scanners for three-color (RGB)...conference paper 2018