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Validation of mitosis counting by automated phosphohistone H3 (PHH3) digital image analysis in a breast carcinoma tissue microarray

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PATHOLOGY 2015年第4期47卷 329-334页

作者： Dessauvagie, B. F. Thomas, C. Robinson, C. Frost, F. A. Harvey, J. Sterrett, G. F. QEII Med Ctr PathWest Lab Med Dept Anat Pathol Nedlands WA 6009 Australia Univ Western Australia Sch Pathol & Lab Med Crawley WA Australia Univ Western Australia Sch Med & Pharmacol Crawley WA Australia

Mitosis counting in H&E stained sections is the most informative constituent of the Nottingham histological grade in breast carcinoma prognosis. Phosphohistone H3 (PHH3) immunohistochemistry (IHC) is a highly specific marker of mitoses, with practical application in identifying mitoses in poorly fixed or distorted tissue and is of prognostic significance in breast carcinoma. Our aim was to assess methods of PHH3 IHC mitosis counting in a tissue microarray (TMA) of 2mm cores from 36 resected breast carcinomas. Mitoses in H&E and PHH3 stained slides were manually scored by pathologist consensus and expressed as counts/2 mm(2). PHH3 stained cores were also evaluated by automated digital image analysis (DIA). Results were compared using Spearman correlation. A strong and significant correlation was observed between manual PHH3 and manual H&E mitotic counts (correlation = 0.81;p< 0.0001) and between automated PHH3 DIA and manual H&E mitotic counts (correlation = 0.79;p< 0.0001). More mitoses were identified with PHH3 IHC than with H&E. Manual and DIA PHH3 counts were strongly and significantly correlated (correlation = 0.83;p< 0.0001) and of similar absolute values. PHH3 DIA is a valid alternative to manual counting with potential application in breast cancer reporting and prognostication.

关键词： Breast carcinoma computer-assisted image processing digital image analysis immunohistochemistry mitotic index PHH3 phosphohistone H3 tissue microarray TMA

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Sub-milliSievert (sub-mSv) CT colonography: a prospective comparison of image quality and polyp conspicuity at reduced-dose versus standard-dose imaging

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EUROPEAN RADIOLOGY 2015年第7期25卷 2089-2102页

作者： Lubner, Meghan G. Pooler, B. Dustin Kitchin, Douglas R. Tang, Jie Li, Ke Kim, David H. del Rio, Alejandro Munoz Chen, Guang-Hong Pickhardt, Perry J. Univ Wisconsin Sch Med & Publ Hlth Dept Radiol Madison WI 53792 USA Univ Wisconsin Sch Med & Publ Hlth Med Phys Madison WI 53792 USA

To prospectively compare reduced-dose (RD) CT colonography (CTC) with standard-dose (SD) imaging using several reconstruction algorithms. Following SD supine CTC, 40 patients (mean age, 57.3 years;17 M/23 F;mean BMI, 27.2) underwent an additional RD supine examination (targeted dose reduction, 70-90 %). DLP, CTDIvol, effective dose, and SSDE were compared. Several reconstruction algorithms were applied to RD series. SD-FBP served as reference standard. Objective image noise, subjective image quality and polyp conspicuity were assessed. Mean CTDIvol and effective dose for RD series was 0.89 mGy (median 0.65) and 0.6 mSv (median 0.44), compared with 3.8 mGy (median 3.1) and 2.8 mSv (median 2.3) for SD series, respectively. Mean dose reduction was 78 %. Mean image noise was significantly reduced on RD-PICCS (24.3 +/- 19HU) and RD-MBIR (19 +/- 18HU) compared with RD-FBP (90 +/- 33), RD-ASIR (72 +/- 27) and SD-FBP (47 +/- 14 HU). 2D image quality score was higher with RD-PICCS, RD-MBIR, and SD-FBP (2.7 +/- 0.4/2.8 +/- 0.4/2.9 +/- 0.6) compared with RD-FBP (1.5 +/- 0.4) and RD-ASIR (1.8 +/- 0.44). A similar trend was seen with 3D image quality scores. Polyp conspicuity scores were similar between SD-FBP/RD-PICCS/RD-MBIR (3.5 +/- 0.6/3.2 +/- 0.8/3.3 +/- 0.6). Sub-milliSievert CTC performed with iterative reconstruction techniques demonstrate decreased image quality compared to SD, but improved image quality compared to RD images reconstructed with FBP. aEuro cent CT colonography dose can be substantially lowered using advanced iterative reconstruction techniques. aEuro cent Iterative reconstruction techniques (MBIR/PICCS) reduce image noise and improve image quality. aEuro cent The PICCS/MBIR-reconstructed, reduced-dose series shows decreased 2D/3D image quality compared to the standard-dose series. aEuro cent Polyp conspicuity was similar on standard-dose images compared to reduced-dose images reconstructed with MBIR/PICCS.

关键词： Computed Tomographic Colonography Radiation Dosage Multidetector Computed Tomography Colonic Neoplasms computer-assisted image processing

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Trans-rectal ultrasound visibility of prostate lesions identified by magnetic resonance imaging increases accuracy of image-fusion targeted biopsies

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WORLD JOURNAL OF UROLOGY 2015年第11期33卷 1669-1676页

作者： Ukimura, Osamu Marien, Arnaud Palmer, Suzanne Villers, Arnauld Aron, Manju Abreu, Andre Luis de Castro Leslie, Scott Shoji, Sunao Matsugasumi, Toru Gross, Mitchell Dasgupta, Prokar Gill, Inderbir S. Univ So Calif Keck Sch Med USC Inst Urol Los Angeles CA 90089 USA Univ So Calif Keck Sch Med Dept Radiol Los Angeles CA 90089 USA Univ So Calif Keck Sch Med Dept Pathol Los Angeles CA 90089 USA Kings Coll London Dept Urol London England

To compare the diagnostic yield of targeted prostate biopsy using image-fusion of multi-parametric magnetic resonance (mp-MR) with real-time trans-rectal ultrasound (TRUS) for clinically significant lesions that are suspicious only on mp-MR versus lesions that are suspicious on both mp-MR and TRUS. Pre-biopsy MRI and TRUS were each scaled on a 3-point score: highly suspicious, likely, and unlikely for clinically significant cancer (sPCa). Using an MR-TRUS elastic image-fusion system (Koelis), a 127 consecutive patients with a suspicious clinically significant index lesion on pre-biopsy mp-MR underwent systematic biopsies and MR/US-fusion targeted biopsies (01/2010-09/2013). Biopsy histological outcomes were retrospectively compared with MR suspicion level and TRUS-visibility of the MR-suspicious lesion. sPCa was defined as biopsy Gleason score a parts per thousand yen7 and/or maximum cancer core length a parts per thousand yen5 mm. Targeted biopsies outperformed systematic biopsies in overall cancer detection rate (61 vs. 41 %;p = 0.007), sPCa detection rate (43 vs. 23 %;p = 0.0013), cancer core length (7.5 vs. 3.9 mm;p = 0.0002), and cancer rate per core (56 vs. 12 %;p < 0.0001), respectively. Highly suspicious lesions on mp-MR correlated with higher positive biopsy rate (p < 0.0001), higher Gleason score (p = 0.018), and greater cancer core length (p < 0.0001). Highly suspicious lesions on TRUS in corresponding to MR-suspicious lesion had a higher biopsy yield (p < 0.0001) and higher sPCa detection rate (p < 0.0001). Since majority of MR-suspicious lesions were also suspicious on TRUS, TRUS-visibility allowed selection of the specific MR-visible lesion which should be targeted from among the multiple TRUS suspicious lesions in each prostate. MR-TRUS fusion-image-guided biopsies outperformed systematic biopsies. TRUS-visibility of a MR-suspicious lesion facilitates image-guided biopsies, resulting in higher detection of significant cancer.

关键词： Prostate neoplasms Magnetic resonance imaging image-guided biopsy Ultrasonography computer-assisted image processing

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Automatic detection of osteoporosis based on hybrid genetic swarm fuzzy classifier approaches

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DENTOMAXILLOFACIAL RADIOLOGY 2016年第7期45卷 20160076-20160076页

作者： Kavitha, Muthu Subash Kumar, Pugalendhi Ganesh Park, Soon-Yong Huh, Kyung-Hoe Heo, Min-Suk Kurita, Takio Asano, Akira An, Seo-Yong Chien, Sung-Il Kyungpook Natl Univ Sch Elect Engn Daegu South Korea Anna Univ Dept Informat Technol Reg Campus Coimbatore Tamil Nadu India Kyungpook Natl Univ Sch Comp Sci & Engn Daegu South Korea Seoul Natl Univ Sch Dent Dept Oral & Maxillofacial Radiol Seoul South Korea Hiroshima Univ Grad Sch Engn Hiroshima Japan Kansai Univ Fac Informat Osaka Japan Kyungpook Natl Univ Sch Dent Dept Oral & Maxillofacial Radiol Daegu South Korea

Objectives: This study proposed a new automated screening system based on a hybrid genetic swarm fuzzy (GSF) classifier using digital dental panoramic radiographs to diagnose females with a low bone mineral density (BMD) or osteoporosis. Methods: The geometrical attributes of both the mandibular cortical bone and trabecular bone were acquired using previously developed software. Designing an automated system for osteoporosis screening involved partitioning of the input attributes to generate an initial membership function (MF) and a rule set (RS), classification using a fuzzy inference system and optimization of the generated MF and RS using the genetic swarm algorithm. Fivefold cross-validation (5-FCV) was used to estimate the classification accuracy of the hybrid GSF classifier. The performance of the hybrid GSF classifier has been further compared with that of individual genetic algorithm and particle swarm optimization fuzzy classifiers. Results: Proposed hybrid GSF classifier in identifying low BMD or osteoporosis at the lumbar spine and femoral neck BMD was evaluated. The sensitivity, specificity and accuracy of the hybrid GSF with optimized MF and RS in identifying females with a low BMD were 95.3%, 94.7% and 96.01%, respectively, at the lumbar spine and 99.1%, 98.4% and 98.9%, respectively, at the femoral neck BMD. The diagnostic performance of the proposed system with femoral neck BMD was 0.986 with a confidence interval of 0.942-0.998. The highest mean accuracy using 5-FCV was 97.9%. with femoral neck BMD. Conclusions: The combination of high accuracy along with its interpretation ability makes this proposed automatic system using hybrid GSF classifier capable of identifying a large proportion of undetected low BMD or osteoporosis at its early stage.

关键词： panoramic radiograph computer-assisted image processing osteoporosis

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Doppler ultrasound compared with electrocardiogram and pulse oximetry cardiac triggering: A pilot study

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MAGNETIC RESONANCE IN MEDICINE 2015年第5期74卷 1257-1265页

作者： Kording, Fabian Schoennagel, Bjoern Lund, Gunnar Ueberle, Friedrich Jung, Caroline Adam, Gerhard Yamamura, Jin Univ Med Ctr Hamburg Eppendorf Ctr Radiol & Endoscopy Dept Diagnost & Intervent Radiol D-20246 Hamburg Germany Hamburg Univ Appl Sci Hamburg Germany

PurposeAccurate triggering of the cardiac cycle is mandatory for optimal image acquisition and thus diagnostic quality in cardiac magnetic resonance imaging. The purpose of this work was to evaluate Doppler ultrasound as an alternative trigger method in cardiac MRI. MethodsSteady-state free precession (SSFP) 2D cine CMR was performed in 11 healthy subjects at 1.5T. Doppler ultrasound (DUS), electrocardiogram (ECG) and pulse oximetry (POX) were used for cardiac triggering. DUS peak detection was verified in comparison to ECG. Quantitative analysis of image quality of each gating method was determined by calculating endocardial border sharpness (EBS) and left ventricular (LV) function parameters and compared with ECG. ResultsMean difference between DUS and ECG in detected RR intervals was 0.04 63 ms (r = 0.96). Trigger jitter was not different between ECG and DUS (P = 0.15) but significant different between ECG and POX (P = 0.01). EBS was similar between each method (3.1 +/- 0.2 / 2.6 +/- 0.2 / 2.9 +/- 0.2 pixel). Mean differences in stroke volume were not significantly different with -1 +/- 7 mL (ECG/DUS, P = 0.9) and 2 +/- 10 mL (ECG/POX, P = 0.8). ConclusionCine cardiac MRI using DUS was successfully demonstrated. DUS triggering is an alternative method for cardiac MRI and may be applied in a clinical setting. Magn Reson Med 74:1257-1265, 2015. (c) 2014 Wiley Periodicals, Inc.

关键词： cine magnetic resonance imaging Doppler ultrasound cardiac-gated imaging techniques oximetry electrocardiogram computer-assisted image processing

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Automatic differentiation of placental perfusion compartments by time-to-peak analysis in mice

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PLACENTA 2015年第3期36卷 255-261页

作者： Kording, F. Forkert, N. D. Sedlacik, J. Adam, G. Hecher, K. Arck, P. Remus, C. C. Univ Med Ctr Hamburg Eppendorf Dept Diagnost & Intervent Radiol Ctr Radiol & Endoscopy D-20246 Hamburg Germany Univ Calgary Calgary AB T2N 1N4 Canada Univ Med Ctr Hamburg Eppendorf Ctr Radiol & Endoscopy Dept Diagnost & Intervent Neuroradiol D-20246 Hamburg Germany Univ Med Ctr Hamburg Eppendorf Ctr Obstet & Paediat Dept Obstet & Fetal Med D-20246 Hamburg Germany

Introduction: The aim of this study was to develop an automatic differentiation of two perfusion compartments within the mouse placenta based on times of maximal contrast enhancement for a detailed and reproducible perfusion assessment. Methods: Placentas (n = 17) from pregnant BALB/c mice (n = 10) were examined in vivo at 7T on gestation day 16.5. Corona] dual-echo 3D TI-weighted gradient-echo sequences were acquired after application of contrast agent for dynamic MRI. An adapted gamma variate function was fitted to the discrete contentration time curves to evaluate the effect of noise on perfusion and segmentation results. Time-to-peak maps based on fitted and discrete curves of each placenta were used to classify each voxel into the high- or low-blood flow compartment using k-means clustering. Perfusion analysis was performed using the steepest slope model and also applied to fitted and discrete curves. Results were compared to manually defined compartments from two independent observers using the Dice coefficient D. Results: Manually defined placental areas of high-flow and low-flow were similar to the automatic segmentation for discrete (D = 0.76/0.75;D = 0.76/0.79) and fitted (D = 0.80/0.80;D = 0.81/0.82) concentration time curves. Mean perfusion values of discrete and fitted curves ranged in the high-flow compartment from 134 to 142 ml/min/100 ml (discrete) vs. 138-143 ml/min/100 ml (fitted) and in the low-flow compartment from 91 to 94 ml/min/100 ml (discrete) vs. 74-82 ml/min/100 ml (fitted). Discussion: Our novel approach allows the automatic differentiation of perfusion compartments of the mouse placenta. The approach may overcome limitations of placental perfusion analyses caused by tissue heterogeneity and a potentially biased selection of regions of interest. (C) 2014 Elsevier Ltd. All rights reserved.

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

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Parameter optimization of a computer-aided diagnosis system for detection of masses on digitized mammograms

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TECHNOLOGY AND HEALTH CARE 2015年第6期23卷 757-774页

作者： Radovic, Milos Milosevic, Marina Ninkovic, Srdjan Filipovic, Nenad Peulic, Aleksandar Univ Kragujevac Kragujevac Serbia Res & Dev Ctr Bioengn Kragujevac Serbia Clin Ctr Kragujevac Kragujevac Serbia

BACKGROUND: Reading mammograms is a difficult task and for this reason any development that may improve the performance in breast cancer screening is of great importance. OBJECTIVE: We proposed optimized computer aided diagnosis (CAD) system, equipped with reliability estimate module, for mass detection on digitized mammograms. METHODS: Proposed CAD system consists of four major steps: preprocessing, segmentation, feature extraction and classification. We propose a simple regression function as a threshold function for extraction of potential masses. By running optimization procedure we estimate parameters of the preprocessing and segmentation steps thus ensuring maximum mass detection sensitivity. In addition to the classification, where we tested seven different classifiers, the CAD system is equipped with reliability estimate module. RESULTS: By performing segmentation 91.3% of masses were correctly segmented with 4.14 false positives per image (FPpi). This result is improved in the classification phase where, among the seven tested classifiers, multilayer perceptron neural network achieved the best result including 77.4% sensitivity and 0.49 FPpi. CONCLUSION: By using the proposed regression function and parameter optimization we were able to improve segmentation results comparing to the literature. In addition, we showed that CAD system has high potential for being equipped with reliability estimate module.

关键词： Breast cancer computer-assisted image processing data mining mammography optimization

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Visualization and quality assessment of the contrast transfer function estimation

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JOURNAL OF STRUCTURAL BIOLOGY 2015年第2期192卷 222-234页

作者： Sheth, Lisa K. Piotrowski, Angela L. Voss, Neil R. Roosevelt Univ Dept Biol Chem & Phys Sci Schaumburg IL 60173 USA

The contrast transfer function (CTF) describes an undesirable distortion of image data from a transmission electron microscope. Many users of full-featured processing packages are often new to electron microscopy and are unfamiliar with the CTF concept. Here we present a common graphical output to clearly demonstrate the CTF fit quality independent of estimation software. Separately, many software programs exist to estimate the four CTF parameters, but their results are difficult to compare across multiple runs and it is all but impossible to select the best parameters to use for further processing. A new measurement is presented based on the correlation falloff of the calculated CTF oscillations against the normalized oscillating signal of the data, called the CTF resolution. It was devised to provide a robust numerical quality metric of every CTF estimation for high-throughput screening of micrographs and to select the best parameters for each micrograph. These new CTF visualizations and quantitative measures will help users better assess the quality of their CTF parameters and provide a mechanism to choose the best CTF tool for their data. (C) 2015 Elsevier Inc. All rights reserved.

关键词： Contrast transfer function Transmission electron microscopy Cryo-electron microscopy methods computer-assisted image processing

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A novel semi-automatic segmentation method for volumetric assessment of the colon based on magnetic resonance imaging

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ABDOMINAL IMAGING 2015年第7期40卷 2232-2241页

作者： Sandberg, Thomas Holm Nilsson, Matias Poulsen, Jakob Lykke Gram, Mikkel Frokjaer, Jens Brondum Ostergaard, Lasse Riis Drewes, Asbjorn Mohr Aalborg Univ Hosp Mech Sense Dept Gastroenterol & Hepatol DK-9000 Aalborg Denmark Aalborg Univ Hosp Mech Sense Dept Radiol DK-9000 Aalborg Denmark Aalborg Univ Dept Hlth Sci & Technol Aalborg Denmark Aalborg Univ Dept Clin Med Aalborg Denmark

To develop a novel semi-automatic segmentation method for quantification of the colon from magnetic resonance imaging (MRI). Fourteen abdominal T2-weighted and dual-echo Dixon-type water-only MRI scans were obtained from four healthy subjects. Regions of interest containing the colon were outlined manually on the T2-weighted images. Segmentation of the colon and feces was obtained using k-means clustering and image registration. Regional colonic and fecal volumes were obtained. Inter-observer agreement between two observers was assessed using the Dice similarity coefficient as measure of overlap. Colonic segmentations showed wide variation in volume and morphology between subjects. Colon volumes of the four healthy subjects for both observers were (median [interquartile range]) ascending colon 200 mL [169.5-260], transverse 200.5 mL [113.5-242.5], descending 148 mL [121.5-178.5], sigmoid-rectum 277 mL [192-345], and total 819 mL [687-898.5]. Overlap agreement for the total colon segmentation between the two observers was high with a Dice similarity coefficient of 0.91 [0.84-0.94]. The colon volume to feces volume ratio was on average 0.7. Regional colon volumes were comparable to previous findings using fully manual segmentation. The method showed good agreement between observers and may be used in future studies of gastrointestinal disorders to assess colon and fecal volume and colon morphology. Novel insight into morphology and quantitative assessment of the colon using this method may provide new biomarkers for constipation and abdominal pain compared to radiography which suffers from poor reliability.

关键词： Colon Magnetic resonance imaging Machine learning Artificial intelligence computer-assisted image processing Constipation

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Effect of exposure parameters and voxel size on bone structure analysis in CBCT

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DENTOMAXILLOFACIAL RADIOLOGY 2015年第8期44卷 art. no. 20150078-art. no. 20150078页

作者： Pauwels, R. Faruangsaeng, T. Charoenkarn, T. Ngonphloy, N. Panmekiate, S. Chulalongkorn Univ Fac Dent Dept Radiol Bangkok Thailand Univ Leuven Biomed Sci Grp Dept Imaging & Pathol OMFS IMPATH Res GrpOral Imaging Ctr Leuven Belgium

Objective: To evaluate the effect of exposure parameters and voxel size on bone structure analysis in dental CBCT. Methods: 20 cylindrical bone samples underwent CBCT scanning (3D Accuitomo 170;J. Morita, Kyoto, Japan) using three combinations of tube voltage (kV) and tube current-exposure time product (mAs), corresponding with a CT dose index of 3.4 mGy: 90 kV and 62 mAs, 73 kV and 108.5 mAs, and 64 kV and 155 mAs. images were reconstructed with a voxel size of 0.080 mm. In addition, the 90 kV scan was reconstructed at voxel sizes of 0.125, 0.160, 0.200, 0.250 and 0.300 mm. The following parameters were measured: bone surface (BS) and bone volume (BV) per total volume (TV), fractal dimension, connectivity density, anisotropy, trabecular thickness (Tb. Th.) and trabecular spacing (Tb. Sp.), structure model index (SMI), plateness, branches, junctions, branch length and triple points. Results: For most parameters, there was no significant effect of the kV value. For BV/TV, "90 kV" differed significantly from the other kV settings;for SMI, "64 vs 73 kV" was significant. For BS/TV, fractal dimension, connectivity density, branches, junctions and triple points values incrementally decreased at larger voxel sizes, whereas an increase was seen for Tb. Th., Tb. Sp., SMI and branch length. For anisotropy and plateness, no (or little) effect of voxel size was seen;for BV/TV, the effect was inconsistent. Conclusions: Most bone structure parameters are not affected by the kV if the radiation dose is constant. Parameters dealing with the trabecular structure are heavily affected by the voxel size.

关键词： cone beam CT bone quality trabecular bone computer-assisted image processing

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