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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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3D printing based on imaging data: review of medical applications

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INTERNATIONAL JOURNAL OF computer assisted RADIOLOGY AND SURGERY 2010年第4期5卷 335-341页

作者： Rengier, F. Mehndiratta, A. von Tengg-Kobligk, H. Zechmann, C. M. Unterhinninghofen, R. Kauczor, H. -U. Giesel, F. L. German Canc Res Ctr Heidelberg Dkfz Dept Radiol E010 D-69120 Heidelberg Germany Univ Heidelberg Hosp Dept Diagnost & Intervent Radiol D-69120 Heidelberg Germany Indian Inst Technol Sch Med Sci & Technol Kharagpur 721302 W Bengal India Univ Heidelberg Hosp Dept Nucl Med D-69120 Heidelberg Germany Univ Karlsruhe Inst Comp Sci & Engn D-76131 Karlsruhe Germany

Purpose Generation of graspable three-dimensional objects applied for surgical planning, prosthetics and related applications using 3D printing or rapid prototyping is summarized and evaluated. Materials and methods Graspable 3D objects overcome the limitations of 3D visualizations which can only be displayed on flat screens. 3D objects can be produced based on CT or MRI volumetric medical images. Using dedicated post-processing algorithms, a spatial model can be extracted from image data sets and exported to machine-readable data. That spatial model data is utilized by special printers for generating the final rapid prototype model. Results Patient-clinician interaction, surgical training, medical research and education may require graspable 3D objects. The limitations of rapid prototyping include cost and complexity, as well as the need for specialized equipment and consumables such as photoresist resins. Conclusions Medical application of rapid prototyping is feasible for specialized surgical planning and prosthetics applications and has significant potential for development of new medical applications.

关键词： Rapid prototyping Patient care Prostheses and implants Medical education computer-assisted image processing

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Urinary stone size estimation: a new segmentation algorithm-based CT method

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EUROPEAN RADIOLOGY 2012年第4期22卷 731-737页

作者： Liden, Mats Andersson, Torbjorn Broxvall, Mathias Thunberg, Per Geijer, Hakan Orebro Univ Hosp Dept Radiol S-70185 Orebro Sweden Univ Orebro Sch Hlth & Med Sci S-70182 Orebro Sweden Univ Orebro Ctr Modelling & Simulat S-70182 Orebro Sweden Orebro Univ Hosp Dept Med Phys S-70185 Orebro Sweden

The size estimation in CT images of an obstructing ureteral calculus is important for the clinical management of a patient presenting with renal colic. The objective of the present study was to develop a reader independent urinary calculus segmentation algorithm using well-known digital image processing steps and to validate the method against size estimations by several readers. Fifty clinical CT examinations demonstrating urinary calculi were included. Each calculus was measured independently by 11 readers. The mean value of their size estimations was used as validation data for each calculus. The segmentation algorithm consisted of interpolated zoom, binary thresholding and morphological operations. Ten examinations were used for algorithm optimisation and 40 for validation. Based on the optimisation results three segmentation method candidates were identified. Between the primary segmentation algorithm using cubic spline interpolation and the mean estimation by 11 readers, the bias was 0.0 mm, the standard deviation of the difference 0.26 mm and the Bland-Altman limits of agreement 0.0 +/- 0.5 mm. The validation showed good agreement between the suggested algorithm and the mean estimation by a large number of readers. The limit of agreement was narrower than the inter-reader limit of agreement previously reported for the same data. The size of kidney stones is usually estimated manually by the radiologist. An algorithm for computer-aided size estimation is introduced. The variability between readers can be reduced. A reduced variability can give better information for treatment decisions.

关键词： X-ray computed tomography Ureteral calculi Kidney stone computer-assisted image processing computer-assisted image interpretation

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Validation of a Web-Based Planning Tool for Percutaneous Cryoablation of Renal Tumors

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CARDIOVASCULAR AND INTERVENTIONAL RADIOLOGY 2020年第11期43卷 1661-1670页

作者： van Oostenbrugge, Tim J. Heidkamp, Jan Moche, Michael Weir, Phil Mariappan, Panchatcharam Flanigan, Ronan Pollari, Mika Payne, Stephen Kolesnik, Marina Jenniskens, Sjoerd F. M. Futterer, Jurgen J. Radboud Univ Nijmegen Med Ctr Dept Urol POB 9101 NL-6500 HB Nijmegen Netherlands Radboud Univ Nijmegen Med Ctr Dept Radiol & Nucl Med Nijmegen Netherlands Univ Hosp Dept Diagnost & Intervent Radiol Leipzig Germany NUMA Engn Serv Ltd Dublin Ireland Aalto Univ Dept Neurosci & Biomed Engn Espoo Finland Univ Oxford Inst Biomed Engn Dept Engn Sci Oxford England Fraunhofer FIT Inst Appl Informat Technol St Augustin Germany Univ Twente Inst Biomed Technol & Tech Med MIRA Enschede Netherlands Indian Inst Technol Dept Math Tirupati Andhra Pradesh India

Purpose To validate a simulation environment for virtual planning of percutaneous cryoablation of renal tumors. Materials and Methods Prospectively collected data from 19 MR-guided procedures were used for validation of the simulation model. Volumetric overlap of the simulated ablation zone volume (sigma) and the segmented ablation zone volume (S;assessed on 1-month follow-up scan) was quantified. Validation metrics were DICE Similarity Coefficient (DSC;the ratio between twice the overlapping volume of both ablation zones divided by the sum of both ablation zone volumes), target overlap (the ratio between the overlapping volume of both ablation zones to the volume ofS;low ratio meansSis underestimated), and positive predictive value (the ratio between the overlapping volume of both ablation zones to the volume of sigma;low ratio meansSis overestimated). Values were between 0 (no alignment) and 1 (perfect alignment), a value > 0.7 is considered good. Results Mean volumes ofSand sigma were 14.8 cm(3)(+/- 9.9) and 26.7 cm(3)(+/- 15.0), respectively. Mean DSC value was 0.63 (+/- 0.2), and >= 0.7 in 9 cases (47%). Mean target overlap and positive predictive value were 0.88 (+/- 0.11) and 0.53 (+/- 0.24), respectively. In 17 cases (89%), target overlap was >= 0.7;positive predictive value was >= 0.7 in 4 cases (21%) and < 0.6 in 13 cases (68%). This indicatesSis overestimated in the majority of cases. Conclusion The validation results showed a tendency of the simulation model to overestimate the ablation effect. Model adjustments are necessary to make it suitable for clinical use.

关键词： Cryosurgery Kidney neoplasms computer-assisted image processing Intraoperative monitoring Preoperative care

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Cavernous transformation of the portal vein: three-dimensional dynamic contrast-enhanced MR angiography

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ABDOMINAL IMAGING 2008年第4期33卷 463-468页

作者： Wang, Li Li, Zhao-shen Lu, Jian-ping Wang, Fei Liu, Qi Tian, Jian-ming Changhai Hosp Dept Gastroenterol Shanghai 200433 Peoples R China Changhai Hosp Dept Radiol Shanghai 200433 Peoples R China

Background: To investigate characteristic features of three-dimensional dynamic contrast- enhanced MR angiography ( 3D DCE-MRA) and validate its clinical significance for the diagnosis of cavernous transformation of the portal vein ( CTPV). Methods: 3D DCE-MRA, along with subsequent data processing using three-dimensional reconstruction, was performed in 33 CTPV patients. We observed 33 emboli in the portal vein, 29 in the left and/or right portal branches, 18 in the superior mesenteric vein, and nine emboli in the splenic vein. Results: The main presentation of CTPV on 3D DCE-MRA was the replacement of the normal configuration of the portal vein by numerous distorted hepatopetal collateral vessels, the presence of arterio-portal venous shunts, and the appearance of hepatofugal collateral vessels in the abdominal cavity and wall. Conclusion: 3D DCE-MRA can be used to simultaneously characterize the portal system and collateral vessels, and can improve the diagnosis and clinical treatment of CTPV.

关键词： cavernous transformation of the portal vein magnetic resonance angiography computer-assisted image processing

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Feasibility of use of medical dual energy scanner for forensic detection and characterization of explosives, a phantom study

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INTERNATIONAL JOURNAL OF LEGAL MEDICINE 2020年第5期134卷 1915-1925页

作者： Ognard, Julien Bourhis, David Cadieu, Romain Grenier, Michel Saccardy, Claire Alavi, Zarrin Ben Salem, Douraied Univ Hosp Brest Forens Imaging Unit F-29609 Brest France Brest Occident Univ UBO Latim INSERM UMR 1101 F-29238 Brest France Univ Hosp Brest Nucl Med Dept F-29609 Brest France Brest Occident Univ UBO GETBO EA 3878 F-29238 Brest France French Minist Interior Explos Ordinance Disposal Off Gen Directorate Civil Secur & Crisis Management F-75008 Paris France Univ Hosp Brest Forens Inst F-29609 Brest France Univ Hosp Brest Clin Invest Ctr 1412 INSERM F-29609 Brest France

Objective Detection of explosives is a challenge due to the use of improvised and concealed bombs. Post-bomb strike bodies are handled by emergency and forensic teams. We aimed to determine whether medical dual-energy computed tomography (DECT) algorithm and prediction model can readily detect and distinguish a range of explosives on the human body during disaster victim identification (DVI) processes of bombings. Materials and Methods A medical DECT of 8 explosives (Semtex, Pastex, Hexamethylene triperoxide diamine, Acetone peroxide, Nitrocellulose, Pentrite, Ammonium Nitrate, and classified explosive) was conducted ex-vivo and on an anthropomorphic phantom. Hounsfield unit (HU), electron density (ED), effective atomic number (Z(eff)), and dual energy index (DEI),were compared by Wilcoxon signed rank test. Intra-class (ICC) and Pearson correlation coefficients (r) were computed. Explosives classification was performed through a prediction model with test-retest samples. Results Except for DEI (p = 0.036), means of HU, ED, and Z(eff) were not statistically different (p > 0.05) between explosives ex-vivo and on the phantom (r > 0.80). Intra- and inter-reader ICC were good to excellent: 0.806 to 0.997 and 0.890, respectively. Except for the phantom DEI, all measurements from each individual explosive differed significantly. HU, ED, Z(eff), and DEI differed depending on the type of explosive. Our decision tree provided Z(eff) and ED for explosives classification with high accuracy (83.7%) and excellent reliability (100%). Conclusion Our medical DECT algorithm and prediction model can readily detect and distinguish our range of explosives on the human body. This would avoid possible endangering of DVI staff.

关键词： Explosives Artificial intelligence Machine learning computer-assisted image processing Forensic medicine

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Functional outcome after partial glossectomy with reconstruction using radial forearm free flap

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AURIS NASUS LARYNX 2013年第3期40卷 303-307页

作者： Joo, Young-Hoon Hwang, Se-Hwan Park, Jun-Ook Cho, Kwang-Jae Kim, Min-Sik Catholic Univ Korea Coll Med Dept Otolaryngol Head & Neck Surg Seoul 137040 South Korea

Objective: The purpose of this study was to investigate the relationship between the radial forearm free flap (RFFF) volume changes and speech and swallowing outcomes. Methods: The study included 18 subjects with squamous cell carcinoma of the oral tongue. Results: Average percentage changes in flap volume between 3 and 12 months was 19.2%. Postoperative free flap volume changes were significantly and negatively correlated with the word and sentence intelligibility (Y= -0.338X + 43.641, r(2) = 0.383, p = 0.006 and Y= -0.246X + 34.322, r(2) = 0.321, p = 0.014, respectively). A significant positive correlation was also found between word and sentence intelligibility and floor of mouth resected, postoperative irradiation. Postoperative flap volume changes between 3 and 12 months were correlated with reduced posterior bolus movement by tongue (p = 0.002), reduced tongue base to posterior pharyngeal wall contact (p = 0.002), reduced laryngeal elevation (p = 0.005), increased aspiration (p = 0.005), delayed oral (p = 0.010) and pharyngeal transit time (p = 0.011). Floor of mouth resected, tongue base resected, and postoperative irradiation also influenced the swallowing outcomes. Conclusions: This study shows that postoperative flap volume changes are significantly related to speech and swallowing outcomes in patients undergoing partial glossectomy reconstructed with RFFF. (C) 2012 Elsevier Ireland Ltd. All rights reserved.

关键词： Surgical flaps Organ size computer-assisted image processing Tongue Treatment outcome

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Complimentary Cardiac Computed Tomography Ventricular Volumetry-Derived Metrics of Severity in Patients with Ebstein Anomaly: Comparison with Echocardiography-Based Severity Indices

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PEDIATRIC CARDIOLOGY 2024年第1期45卷 24-31页

作者： Goo, Hyun Woo Park, Sang Hyub Univ Ulsan Asan Med Ctr Coll Med Dept Radiol 88 Olymp Ro43 Gil Seoul 05505 South Korea Univ Ulsan Res Inst Radiol Asan Med Ctr 88 Olymp Ro43 Gil Seoul 05505 South Korea

Detailed three-dimensional cardiac segmentations using cardiac computed tomography (CT) data is technically feasible in patients with Ebstein anomaly, but its complementary role has not been evaluated. This single-center, retrospective study was aimed to evaluate the complementary role of cardiac CT ventricular volumetry in evaluating the severity of Ebstein anomaly. Preoperative cardiac CT ventricular volumetry was performed in 21 children with Ebstein anomaly. CT-based ventricular functional measures were compared between Carpentier types, and between definitive surgical repair types. The Celermajer severity index measured with echocardiography was correlated with CT-based functional parameters. Total right ventricle (RV) and functional RV (fRV) volumes, fRV fraction, fRV/left ventricle (LV) volume ratio, and end-diastolic CT severity index demonstrated statistically significant differences between Carpentier type A/B and Carpentier type C/D (p < 0.05). The Celermajer severity index measured with echocardiography showed a high positive correlation with the end-diastolic CT severity index (R = 0.720, p < 0.002). There were no statistically significant differences in both echocardiography- and CT-based functional measures between patients with biventricular repair and patients with one-and-a-half or univentricular repair (p > 0.05). Compared with echocardiography, cardiac CT ventricular volumetry can provide the severity of Ebstein anomaly objectively and may be used in select patients when echocardiographic results are inconclusive or inconsistent.

关键词： Computed tomography angiography computer-assisted image processing Ebstein anomaly Severity of illness index Ventricular function

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Semi-automatic magnetic resonance imaging based orbital fat volumetry: reliability and correlation with computed tomography

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INTERNATIONAL JOURNAL OF ORAL AND MAXILLOFACIAL SURGERY 2021年第3期50卷 416-422页

作者： Willaert, R. Degrieck, B. Orhan, K. Deferm, J. Politis, C. Shaheen, E. Jacobs, R. Ghent Univ Hosp Dept Head & Neck Surg Ghent Belgium Univ Hosp Leuven Dept Oral & Maxillofacial Surg Herestr 49 B-3000 Leuven Belgium Ghent Univ Hosp Dept Radiol Ghent Belgium Katholieke Univ Leuven OMFS IMPATH Res Grp Fac Med Dept Imaging & Pathol Leuven Belgium Ankara Univ Dept DentoMaxillofacial Radiol Fac Dent Ankara Turkey Radboud UMC Dept Oral & Maxillofacial Surg Nijmegen Netherlands Karolinska Inst Dept Dent Med Stockholm Sweden

Post-processing analysis can provide valuable information for diagnosis and planning of orbital disorders. This cross-sectional study aims to evaluate the reliability of semi-automatic, orbital fat volumetry using magnetic resonance imaging (MRI). Two observers assessed the orbital fat volume using a standard MRI protocol (3T, T1w sequence) in 12 orbits diagnosed with Graves' orbitopathy (GO) and 10 healthy control orbits. MRI and computed tomography (CT) based analysis were compared. Intra-observer variability was good (intraclass correlation coefficient (ICC) 0.88;95% confidence interval (CI) [0.70, 0.95]) and interobserver agreement was moderate (ICC 0.55;95% CI [-0.09, 0.81]), which corresponds to a mean percentage difference of 1.3% and 17.9% of the total orbital fat volume. Mean differences between MRI and CT measurements were, respectively, 1.1 cm(3) (P= 0.064, 95% CI [-0.20, 2.43]) and 1.4 cm(3) (P=0.016, 95% CI [0.21, 2.56]) for the control and the GO group. MRI volumetry was strongly correlated with CT (Pearson's r= 0.7, P<0.001). We conclude that orbital fat volumetry is feasible with a semi-automatic segmentation procedure and standard MRI protocol. Correlation with CT volumetry is good, but considerable bias may derive from observer variability and these errors should be taken into account for the purpose of volumetric analysis. Better definition of error sources may increase measurement accuracy.

关键词： computed tomography magnetic resonance imaging Graves' Orbitopathy orbit computer-assisted image processing

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Outlining of the detailed structures in sectioned images from Visible Korean

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SURGICAL AND RADIOLOGIC ANATOMY 2012年第3期34卷 235-247页

作者： Shin, Dong Sun Park, Jin Seo Park, Hyo Seok Hwang, Sung Bae Chung, Min Suk Ajou Univ Sch Med Dept Anat Suwon 443749 South Korea Dongguk Univ Coll Med Dept Anat Gyeongju 780714 South Korea Kyungbuk Coll Dept Phys Therapy Youngju 750712 South Korea

Sectioned images of cadavers enable creation of realistic three-dimensional (3D) models. In order to build a 3D model of a structure, the structure has to be outlined in the sectioned images. The outlining process is time consuming;therefore, users want to be provided with outlined images. The more detailed structures are outlined, the greater potential for wider application of the outlined images. In the Visible Korean, sectioned images (intervals 0.2 mm) of the entire body of a male cadaver were prepared. In the available 1,702 sectioned images (intervals 1 mm), 937 structures were outlined over a period of 8 years. The outlined images were altered to black-filled images for each structure;black-filled images were selected for distribution in order to maintain small file sizes. We attempted to determine whether black-filled images could be used in various situations. The outlines of these images were interpolated for production of new images at 0.2 mm intervals. The outlines were then filled with different colors for construction of color-filled images of all structures. Volume and surface reconstructions of the black-filled images were executed in order to build volume and surface models. The black-filled images with corresponding sectioned images presented here are the source of realistic 3D models for use in medical simulation systems.

关键词： Visible Human Projects Cadaver Frozen sections computer-assisted image processing Three-dimensional imaging

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