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Treatment assessment based on computerized lymph node volume and ratio of necrotic area in tuberculous cervical lymphadenitis

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AURIS NASUS LARYNX 2012年第4期39卷 402-406页

作者： Joo, Young-Hoon Hwang, Se-Hwan Seo, Jae-Hyun Kang, Jun-Myung Catholic Univ Korea Coll Med Bucheon St Marys Hosp Dept Otolaryngol Head & Neck Surg Seoul 420717 South Korea

Objective: The objective of this study was to investigate the feasibility of computerized segmentation of lymph nodes to evaluate the relationship of treatment outcomes in tuberculous cervical lymphadenitis (TCL). Methods: The study included 52 subjects with TCL that had CT before standard medical treatment. The relationship between the medication treatment response, volume and ratio of necrotic area of the largest lymph node in patients with TCL was evaluated. The treatment outcome was defined as the 'responder' (n = 35) and 'non-responder' (n = 17) groups. Seventeen non-responder patients required surgery. Results: The average lymph node volumes and ratio of necrotic area were 58.59 cm(3) (range, 4.96-249.48 cm(3)) and 0.30 (range, 0-0.59), respectively. There was a significant difference in the lymph node volumes (34.91 +/- 24.00 cm(3) vs. 107.04 +/- 69.12 cm(3), p < 0.001) and ratio of necrotic area (0.26 +/- 0.12 vs. 0.40 +/- 0.14,p = 0.001) between responders and non-responders. The receiver-operating-characteristic (ROC) curve analysis was used for differentiating responders from non-responders;it showed that the area under the curve for the lymph node volumes and ratio of necrotic area was 0.845 and 0.759, respectively. The cut-off value for the lymph node volumes and ratio of necrotic area was 44.15 cm(3) and 0.36 based on the ROC curve. Conclusions: A large lymph node volume and high ratio of necrotic area on the 3D reconstruction of CT images were associated with the response to medical treatment for TB. These findings might be useful for assessing treatment outcomes. (C) 2011 Elsevier Ireland Ltd. All rights reserved.

关键词： Lymph node tuberculosis computer-assisted image processing Spiral computed tomography Treatment outcomes

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Evaluation of an improved technique for lumen path definition and lumen segmentation of atherosclerotic vessels in CT angiography

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EUROPEAN RADIOLOGY 2007年第7期17卷 1738-1745页

作者： van Velsen, Evert F. S. Niessen, Wiro J. de Weert, Thomas T. de Monye, Cecile van der Lugt, Aad Meijering, Erik Stokking, Rik Erasmus MC Univ Med Ctr Rotterdam Dept Radiol Biomed Imaging Grp Rotterdam NL-3015 GE Rotterdam Netherlands Erasmus MC Univ Med Ctr Rotterdam Dept Med Informat Biomed Imaging Grp Rotterdam NL-3015 GE Rotterdam Netherlands Erasmus MC Univ Med Ctr Rotterdam Dept Radiol NL-3015 GE Rotterdam Netherlands

Vessel image analysis is crucial when considering therapeutical options for (cardio-) vascular diseases. Our method, VAMPIRE (Vascular Analysis using Multiscale Paths Inferred from Ridges and Edges), involves two parts: a user defines a start- and endpoint upon which a lumen path is automatically defined, and which is used for initialization;the automatic segmentation of the vessel lumen on computed tomographic angiography (CTA) images. Both parts are based on the detection of vessel-like structures by analyzing intensity, edge, and ridge information. A multi-observer evaluation study was performed to compare VAMPIRE with a conventional method on the CTA data of 15 patients with carotid artery stenosis. In addition to the start- and endpoint, the two radiologists required on average 2.5 (SD: 1.9) additional points to define a lumen path when using the conventional method, and 0.1 (SD: 0.3) when using VAMPIRE. The segmentation results were quantitatively evaluated using Similarity Indices, which were slightly lower between VAMPIRE and the two radiologists (respectively 0.90 and 0.88) compared with the Similarity Index between the radiologists (0.92). The evaluation shows that the improved definition of a lumen path requires minimal user interaction, and that using this path as initialization leads to good automatic lumen segmentation results.

关键词： arteries spiral computed tomography diagnostic imaging cardiovascular diseases computer-assisted image processing

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Digital radiographic measurement of approximal caries progression in fluoridated and non-fluoridated areas of Rio de Janeiro, Brazil

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COMMUNITY DENTISTRY AND ORAL EPIDEMIOLOGY 1997年第6期25卷 412-418页

作者： Lawrence, HP Benn, DK Sheiham, A UCL Dept Epidemiol & Publ Hlth London England London Hosp Coll Med Dept Dent Publ Hlth London E1 1BB England Univ Florida Coll Dent Dept Oral Surg & Diagnost Sci Gainesville FL USA

The effect of fluoridation on approximal caries progression was investigated using serial digitized bitewing images and conventional film images of 290 12-16-year-old schoolchildren who were lifetime residents of either Rio de Janeiro (a fluoridated area) or Mangaratiba and Angra dos Reis (non-fluoridated areas) in the state of Rio de Janeiro, Brazil. One examiner scored a maximum of 28 approximal surfaces of posterior teeth per subject using both methods. The intraexaminer reliability for rating lesion depth with digital images was comparable with that of the conventional bitewing films (namely, intraclass correlation of 0.99 and weighted Kappa scores of 0.82, respectively). Approximal surface D1S was 3.17+/-0.25 (s(x)) in fluoridated areas and 6.64+/-0.44 in non-fluoridated areas. After 1 year, the rate of caries progression in approximal surfaces was significantly lower in the fluoridated areas (0.54+/-0.14) as compared with the non-fluoridated areas (1.41+/-0.20) using Pitts' scoring system for conventional bitewing radiographs (P<0.001). Similarly, the digital radiographic method was able to detect subtle differences in approximal caries progression in the enamel and the dentin (overall mean: 0.34 mm/year in fluoridated areas vs 0.49 mm/year in nonfluoridated areas, P<0.05). The two radiographic methods were strongly correlated (r(s)=0.7). Assuming a constant rate over time, these results indicate that lesion progression from the outer half of the enamel into the outer half of the dentin takes approximately 3-4 years in schoolchildren from the fluoridated areas compared to 2 1/2 years in the non-fluoridated areas.

关键词： adolescence bitewing radiography caries progression computer-assisted image processing digital radiography fluoridation

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Macroanatomy and 3D probabilistic atlas of the human insula

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NEUROimage 2017年 150卷 88-98页

作者： Faillenot, Isabelle Heekemann, Rolf A. Frot, Maud Hammers, Alexander Hop Nord St Etienne Neurol Dept F-42055 St Etienne France Lyon Ctr Neurosci CRNL INSERM1028 Cent Integrat Pain Unit F-69675 Lyon France Neurodis Fdn F-69675 Lyon France Univ Gothenburg MedTech West Sahlgrenska Univ Hosp Gothenburg Sweden Imperial Coll London Div Brain Sci London England Claude Bernard Univ Lyon 1 F-69000 Villeurbanne France Kings Coll London London England Kings Coll London Guys & St Thomas PET Ctr Div Imaging Sci & Biomed Engn London England

The human insula is implicated in numerous functions. More and more neuroimaging studies focus on this region, however no atlas offers a complete subdivision of the insula in a reference space. The aims of this study were to define a protocol to subdivide insula, to create probability maps in the MNI152 stereotaxic space, and to provide normative reference volume measurements for these subdivisions. Six regions were manually delineated bilaterally on 3D T1 MR images of 30 healthy subjects: the three short gyri, the anterior inferior cortex, and the two long gyri. The volume of the insular grey matter was 7.7 +/- 0.9 cm(3) in native space and 9.9 +/- 0.6 cm(3) in MNI152 space. These volumes expressed as a percentage of the ipsilateral grey matter volume were minimally larger in women (2.7 +/- 0.2%) than in men (2.6 +/- 0.2%). After spatial normalization, a stereotactic probabilistic atlas of each subregion was produced, as well as a maximum-probability atlas taking into account surrounding structures. Automatically labelling insular subregions via a multi-atlas propagation and label fusion strategy (MAPER) in a leave-one-out experiment showed high spatial overlaps of such automatically defined insular subregions with the manually derived ones (mean Jaccard index 0.65, corresponding to a mean Dice index of 0.79), with an average mean volume error of 2.6%. Probabilistic and maximum probability atlases and the original delineations are available on the web under free academic licences.

关键词： Neuroanatomy Insula anatomy computer-assisted image processing Magnetic resonance imaging methods Statistics and numerical data Neurological models Sex characteristics

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Automated nasopharyngeal carcinoma detection with dynamic gadolinium-enhanced MR imaging

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METHODS OF INFORMATION IN MEDICINE 2001年第4期40卷 331-337页

作者： Hsu, CC Lai, PH Lee, C Huang, WC Natl Sun Yat Sen Univ Dept Comp Sci & Engn Kaohsiung 80424 Taiwan Kaohsiung Vet Gen Hosp Dept Radiol Kaohsiung Taiwan Chia Nan Univ Pharm & Sci Dept Management Informat Syst Tainan Taiwan Yung Ta Inst Technol & Commerce Pingtung Taiwan

Objectives. The purpose of this research is to develop an automatic medical diagnosis for segmenting nasopharyngeal carcinoma (NPC) with dynamic gadolinium-enhanced MR imaging. Methods: This system is a multistage process, involving motion correction, head mask generation, dynamic MR data quantitative evaluation, rough segmentation, and rough segmentation refinement. Two approaches, a relative signal increase method and a slope method, are proposed for the quantitative evaluation of dynamic MR data. Results. The NPC detection results obtained using the proposed methods had a rating of 85% in match percent compared with these lesions identified by an experienced radiologist. The match percent for the two proposed methods did not have significant differences. However, the computation cost for the slope method was about twelve times faster than the relative signal increase method. Conclusions. The proposed methods can identify the NPC regions quickly and effectively. This system can enhance the performance of clinical diagnosis.

关键词： nasopharyngeal neoplasms computer-assisted image processing magnetic resonance imaging motion pharmacokinetics

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Boosting in Nonlinear Regression Models with an Application to DCE-MRI Data

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METHODS OF INFORMATION IN MEDICINE 2016年第1期55卷 31-41页

作者： Feilke, M. Bischl, B. Schmid, V. J. Gertheiss, J. Univ Munich Inst Stat D-80539 Munich Germany Tech Univ Dortmund Fak Stat D-44221 Dortmund Germany Univ Gottingen Dept Nutztierwissensch D-37073 Gottingen Germany Univ Gottingen Zentrum Stat D-37073 Gottingen Germany

Background: For the statistical analysis of dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) data, compartment models are a commonly used tool. By these models, the observed uptake of contrast agent in some tissue over time is linked to physiologic properties like capillary permeability and blood flow. Up to now, models of different complexity have been used, and it is still unclear which model should be used in which situation. In previous studies, it has been found that for DCE-MRI data, the number of compartments differs for different types of tissue, and that in cancerous tissue, it might actually differ over a region of voxels of one DCE-MR image. Objectives: To find the appropriate number of compartments and estimate the parameters of a regression model for each voxel in an DCE-MR image. With that, tumors in an DCE-MR image can be located, and for example therapy success can be assessed. Methods: The observed uptake of contrast agent in a voxel of an image of some tissue is described by a concentration time curve. This curve can be modeled using a nonlinear regression model. We present a boosting approach with nonlinear regression as base procedure, which allows us to estimate the number of compartments and the related parameters for each voxel of an DCE-MR image. In addition, a spatially regularized version of this approach is proposed. Results: With the proposed approach, the number of compartments - and with that the complexity of the model - per voxel is not fixed but data-driven, which allows us to fit models of adequate complexity to the concentration time curves of all voxels. The parameters of the model remain nevertheless interpretable because of the underlying compartment model. Conclusions: The proposed boosting approaches outperform all competing methods considered in this paper regarding the correct localization of tumors in DCE-MR images as well as the spatial homogeneity of the estimated number of compartments across the image, and

关键词： Statistical computing computer-assisted image processing statistical models algorithms regression analysis spatial regulariza tion biological models magnetic resonance imaging

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Creating normograms of dural sinuses in healthy persons using computer-assisted detection for analysis and comparison of cross-section dural sinuses in the brain

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JOURNAL OF CLINICAL NEUROSCIENCE 2017年第0期40卷 190-194页

作者： Anconina, Reut Zur, Dinah Kesler, Anat Lublinsky, Svetlana Toledano, Ronen Novack, Victor Benkobich, Elya Novoa, Rosa Novic, Evelyne Farkash Shelef, Ilan Ben Gurion Univ Negev Soroka Univ Med Ctr Radiol Inst Beer Sheva Israel Tel Aviv Univ Sourasky Med Ctr Ophthalmol Div Tel Aviv Israel Ben Gurion Univ Negev Dept Biomed Engn Beer Sheva Israel Ben Gurion Univ Negev Soroka Univ Med Ctr Clin Res Ctr Beer Sheva Israel

Dural sinuses vary in size and shape in many pathological conditions with abnormal intracranial pressure. Size and shape normograms of dural brain sinuses are not available. The creation of such normograms may enable computer-assisted comparison to pathologic exams and facilitate diagnoses. The purpose of this study was to quantitatively evaluate normal magnetic resonance venography (MRV) studies in order to create normograms of dural sinuses using a computerized algorithm for vessel cross-sectional analysis. This was a retrospective analysis of MRV studies of 30 healthy persons. Data were analyzed using a specially developed Matlab algorithm for vessel cross-sectional analysis. The cross-sectional area and shape measurements were evaluated to create normograms. Mean cross-sectional size was 53.27 +/- 13.31 for the right transverse sinus (TS), 46.87 + 12.57 for the left TS (p = 0.089) and 36.65 + 12.38 for the superior sagittal sinus. Normograms were created. The distribution of cross-sectional areas along the vessels showed distinct patterns and a parallel course for the median, 25th, 50th and 75th percentiles. In conclusion, using a novel computerized method for vessel cross-sectional analysis we were able to quantitatively characterize dural sinuses of healthy persons and create normograms. (C) 2017 Elsevier Ltd. All rights reserved.

关键词： Neuroimaging Magnetic resonance imaging Intracranial pressure computer-assisted image processing

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DCE MRI reveals early decreased and later increased placenta perfusion after a stress challenge during pregnancy in a mouse model

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PLACENTA 2018年 65卷 15-19页

作者： Remus, Chressen Catharina Kording, Fabian Arck, Petra Solano, Emilia Sedlacik, Jan Adam, Gerhard Hecher, Kurt Forkert, Nils Daniel Univ Med Ctr Hamburg Eppendorf Ctr Radiol & Endoscopy Dept Diagnost & Intervent Radiol & Nucl Med Martinistr 52 D-20246 Hamburg Germany Univ Med Ctr Hamburg Eppendorf Ctr Obstet & Paediat Dept Obstet & Fetal Med Martinistr 52 D-20246 Hamburg Germany Univ Med Ctr Hamburg Eppendorf Ctr Radiol & Endoscopy Dept Diagnost & Intervent Neuroradiol Martinistr 52 D-20246 Hamburg Germany Univ Calgary Dept Radiol 3330 Hosp Dr NW Calgary AB T2N 4N1 Canada Univ Calgary Hotchkiss Brain Inst 3330 Hosp Dr NW Calgary AB T2N 4N1 Canada

Objectives: Stress during pregnancy is known to have negative effects on fetal outcome. The purpose of this exploratory study was to examine placental perfusion alterations after stress challenge during pregnancy in a mouse model. Material and Methods: Seven Tesla MRI was performed on pregnant mice at embrionic day (ED) 14.5 and 16.5. Twenty dams were exposed to an established acoustic stress challenge model while twenty nonexposed dams served as controls. Placental perfusion was analyzed in dynamic contrast-enhanced (DCE) MRI using the steepest slope model. The two functional placental compartments, the highly vascularized labyrinth and the endocrine junctional zone, were assessed separately. Results: Statistical analysis revealed decreased perfusion levels in the stress group at ED 14.5 compared to controls in both placenta compartments. On ED 16.5, the perfusion level increased significantly in the stress group while placenta perfusion in controls remained similar or even slightly decreased leading to an overall increased perfusion in the stress group on ED 16.5 compared to controls. Conclusion: MR imaging allows noninvasive placenta perfusion assessment in this fetal stress mimicking animal model. In this exploratory study, we demonstrated that stress challenge during pregnancy leads to an initial reduction followed by an increase of placenta perfusion. (C) 2018 Elsevier Ltd. All rights reserved.

关键词： Magnetic resonance imaging Placenta Perfusion computer-assisted image processing IUGR

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Partial voxel interpolation to reduce partial volume error of cardiac computed tomography ventricular volumetry in patients with congenital heart disease

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PEDIATRIC RADIOLOGY 2023年第12期53卷 2528-2538页

作者： Goo, Hyun Woo Park, Sang Hyub Univ Ulsan Res Inst Radiol Coll Med Asan Med Ctr 88 Olymp Ro 43 Gil Seoul 05505 South Korea Univ Ulsan Coll Med Dept Radiol 88 Olymp Ro 43 Gil Seoul 05505 South Korea

Background Varying degrees of partial volume error depending on the complexity of the endocardial borders are inevitable in threshold-based cardiac computed tomography (CT) ventricular volumetry. These errors can potentially be reduced by using a partial voxel interpolation (PVI) method, but this has not been tested for cardiac CT ventricular *** To evaluate the partial volume error-reducing effects of the PVI method in cardiac CT ventricular volumetry among patients with congenital heart disease (CHD).Materials and methods The cardiac CT ventricular volumetry data were obtained from 55 patients (median age 12.0 years) with CHD. The ventricular and myocardial volumes, ejection fraction and ventricular mass-volume ratio were quantified and compared before and after the PVI method. The correlation between the myocardial volumes in the end-systolic and end-diastolic phases was tested. The effect of the PVI method on the classification of ventricular hypertrophy was *** The indexed ventricular volumes after PVI were significantly smaller (7.4-11.5%) than those before PVI (P<0.001). In contrast, the indexed myocardial volumes were significantly larger (6.2-27.7%) after PVI (P<0.001). The ejection fractions and mass-volume ratios were significantly larger (1.6-2.2% and 19.7-42.5%, respectively) after PVI (PP<0.001, respectively). The indexed myocardial masses showed prominently high correlation between the end-systolic and end-diastolic phases (R, 0.961-0.990;P<0.001). The proportions of no and severe hypertrophy were significantly decreased (P<0.002) and increased (P<0.032), respectively, after the application of the PVI *** The PVI method can reduce partial volume error in cardiac CT ventricular volumetry among patients with CHD.

关键词： Computed tomography angiography computer-assisted image processing Congenital heart defects Partial voxel interpolation Threshold-based segmentation Ventricular function

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Artificial intelligence and machine learning in oncologic imaging

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ONKOLOGE 2020年第1期26卷 60-65页

作者： Kleesiek, Jens Murray, Jacob M. Kaissis, Georgios Braren, Rickmer German Canc Res Ctr Dept Radiol AG Computat Radiol Heidelberg Germany German Canc Consortium DKTK Heidelberg Germany Tech Univ Munich Sch Med Dept Diagnost & Intervent Radiol Munich Germany

Background. Machine learning (ML) is finding entry into many areas of society, including medicine. This transformation has the potential to drastically change the perception of medicine and medical practice. While these advances currently only influence clinical routine in isolated cases, they also come with risks. These aspects become particularly clear when considering the different stages of oncologic patient care and the involved interdisciplinary and intermodality interactions. In recent publications, computers-in collaboration with humans or alone-have been outperforming humans. This pertains to tumor identification, tumor classification, creation of prognoses, and evaluation of treatments. Additionally, ML algorithms, e.g., artificial neural networks (ANNs), which constitute the drivers behind many of the latest achievements in ML, can deliver this level of performance in a reproducible, fast, and cheap manner. Objective. This review elucidates the current state of research on ML in oncology by focusing on selected tumor entities, and relates this to the development of research and medicine as a whole. Materials and methods. This work is based on a selective literature search in the databases PubMed and arXiv. Conclusion. In the future, AI applications will develop into an integral part of the medical profession and offer advantages for oncologic diagnostics and treatment.

关键词： Machine learning computer-assisted image processing Diagnostic imaging Deep Learning Neural networks (computer)

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