Physics-aware learning and domain-specific loss design in ophthalmology.

The human cataract, a developing opacification of the human eye lens, currently constitutes the world's most frequent cause for blindness. As a result, cataract surgery has become the most frequently performed ophthalmic surgery in the world. By removing the human lens and replacing it with an artificial intraocular lens (IOL), the optical system of the eye is restored.

Automated Retinal Image Analysis for Evaluation of Focal Hyperpigmentary Changes in Intermediate Age-Related Macular Degeneration.

Purpose: To develop and evaluate a software tool for automated detection of focal hyperpigmentary changes (FHC) in eyes with intermediate age-related macular degeneration (AMD).

Methods: Color fundus (CFP) and autofluorescence (AF) photographs of 33 eyes with FHC of 28 AMD patients (mean age 71 years) from the prospective longitudinal natural history MODIAMD-study were included. Fully automated to semiautomated registration of baseline to corresponding follow-up images was evaluated.

Crystal structure of (1-eth-oxy-ethyl-idene)di-methyl-aza-nium tetra-phenyl-borate.

In the cation of the title salt, C6H14NO(+)·C24H20B(-), the C-N bond lengths are 1.297 (2), 1.464 (2) and 1.

Crystal structure of (eth-oxy-ethyl-idene)di-methyl-aza-nium ethyl sulfate.

In the title salt, C6H14NO(+)·C2H5SO4 (-), the C-N bond lengths in the cation are 1.2981 (14), 1.4658 (14) and 1.

(But-oxy-methyl-idene)di-methyl-aza-nium tetra-phenyl-borate aceto-nitrile monosolvate.

In the title solvated salt, C7H16NO(+)·C24H20B(-)·C2H3N, the C-N bond lengths in the cation are 1.2831 (19), 1.467 (2) and 1.

(Meth-oxy-methyl-idene)di-methyl-aza-nium tetra-phenyl-borate aceto-nitrile monosolvate.

In the cation of the title salt, C4H10NO(+)·C24H20B(-)·C2H3N, the C-N bond lengths are 1.2864 (16), 1.4651 (17) and 1.

3-Methyl-4,5-di-hydro-oxazolium tetra-phenyl-borate.

In the cation of the title salt, C4H8NO(+)·C24H20B(-), the C-N bond lengths are 1.272 (2), 1.4557 (19) and 1.

Choosing the optimal wall shear parameter for the prediction of plaque location-A patient-specific computational study in human left coronary arteries.

Objective: While the correlation of atherosclerotic plaque locations with local wall shear stress magnitude has been evaluated previously by other investigators in both right (RCA) and left coronary arteries (LCA), the relative performance of average wall shear stress (AWSS), average wall shear stress gradient (AWSSG), oscillatory shear index (OSI) and relative residence time (RRT) as indicators of potential atherosclerotic plaque locations has not been studied for the LCA. Here we determine the performance of said wall shear parameters in the LCA for the prediction of plaque development locations and compare these results to those previously found in the RCA.

Methods: We obtained 30 patient-specific geometries (mean age 67.

Computer-aided detection of ground glass nodules in thoracic CT images using shape, intensity and context features.

Ground glass nodules (GGNs) occur less frequent in computed tomography (CT) scans than solid nodules but have a much higher chance of being malignant. Accurate detection of these nodules is therefore highly important. A complete system for computer-aided detection of GGNs is presented consisting of initial segmentation steps, candidate detection, feature extraction and a two-stage classification process.

Computed high concentrations of low-density lipoprotein correlate with plaque locations in human coronary arteries.

Subendothelial accumulation of low-density lipoprotein (LDL) in arterial walls is an initiator of atherosclerotic plaque formation. We report here on the correlation between healthy state subendothelial LDL concentration distribution and sites of subsequent plaque formation in coronary arteries of patients with coronary artery disease (CAD). We acquired left (LCA) and right coronary artery (RCA) and atherosclerotic plaque geometries of 60 patients with CAD using dual-source computed tomography angiography.

Choosing the optimal wall shear parameter for the prediction of plaque location-A patient-specific computational study in human right coronary arteries.

Background: Average wall shear-stress (AWSS), average wall shear-stress gradient (AWSSG), oscillatory shear index (OSI) and relative residence time (RRT) are believed to predict areas vulnerable to plaque formation in the coronary arteries. Our aim was to analyze the correlation of these parameters in patients' vessels before the onset of atherosclerosis to the specific plaque sites thereafter, and to compare the parameters' sensitivity and positive predictive value.

Methods: We obtained 30 patient-specific geometries (mean age 67.

Effect of reader experience on variability, evaluation time and accuracy of coronary plaque detection with computed tomography coronary angiography.

Objective: To assess the effect of reader experience on variability, evaluation time and accuracy in the detection of coronary artery plaques with computed tomography coronary angiography (CTCA).

Methods: Three independent, blinded readers with three different experience levels twice labelled 50 retrospectively electrocardiography (ECG)-gated contrast-enhanced dual-source CTCA data sets (15 female, age 67.3 +/- 10.

Guided review by frequent itemset mining: additional evidence for plaque detection.

Purpose: A guided review process to support manual coronary plaque detection in computed tomography coronary angiography (CTCA) data sets is proposed. The method learns the spatial plaque distribution patterns by using the frequent itemset mining algorithm and uses this knowledge to predict potentially missed plaques during detection.

Materials And Methods: Plaque distribution patterns from 252 manually labeled patients who underwent CTCA were included.

Prediction rules for the detection of coronary artery plaques: evidence from cardiac CT.

Objectives: To evaluate spatial plaque distribution patterns in coronary arteries based on computed tomography coronary angiography data sets and to express the learned patterns in prediction rules. An application is proposed to use these prediction rules for the detection of initially missed plaques.

Material And Methods: Two hundred fifty two consecutive patients with chronic coronary artery disease underwent contrast-enhanced dual-source computed tomography coronary angiography for clinical indications.

Patient-specific three-dimensional simulation of LDL accumulation in a human left coronary artery in its healthy and atherosclerotic states.

We calculate low-density lipoprotein (LDL) transport from blood into arterial walls in a three-dimensional, patient-specific model of a human left coronary artery. The in vivo anatomy data are obtained from computed tomography images of a patient with coronary artery disease. Models of the artery anatomy in its healthy and diseased states are derived after segmentation of the vessel lumen, with and without the detected plaque, respectively.

Identification of atherosclerotic lesion-prone sites through patient-specific simulation of low-density lipoprotein accumulation.

We present a patient-specific model of low-density lipoprotein (LDL) transport from blood into arterial walls. To this end, the arterial endothelium is represented by a shear-stress dependent three-pore model taking into account blood plasma and LDL passage through the vesicular pathway, normal junctions and leaky junctions. We virtually remove atherosclerotic plaque from an in-vivo left coronary artery computed tomography (CT) dataset to obtain an approximation of the artery anatomy in its healthy state.

Automatic detection of calcified coronary plaques in computed tomography data sets.

The detection of calcified plaques is an essential step in the assessment of coronary heart diseases. However, manual plaque segmentation is subjected to intra- and inter-observer variability. We present a novel framework for the automatic detection of calcified coronary plaques in Computed Tomography images.

ACCURATUM: improved calcium volume scoring using a mesh-based algorithm--a phantom study.

To overcome the limitations of the classical volume scoring method for quantifying coronary calcifications, including accuracy, variability between examinations, and dependency on plaque density and acquisition parameters, a mesh-based volume measurement method has been developed. It was evaluated and compared with the classical volume scoring method for accuracy, i.e.