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Application of two segmentation protocols during the processing of virtual images in rapid prototyping: ex vivo study with human dry mandibles

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CLINICAL ORAL INVESTIGATIONS 2013年第9期17卷 2113-2118页

作者： Ferraz, Eduardo Gomes Safira Andrade, Lucio Costa dos Santos, Aline Rode Torregrossa, Vinicius Rabelo Fischer Rubira-Bullen, Izabel Regina Sarmento, Viviane Almeida Univ Fed Bahia Sch Dent BR-41110150 Salvador BA Brazil State Univ Sao Paulo Bauru Sch Dent BR-17012101 Bauru SP Brazil Univ Estadual Feira de Santana Sch Dent Feira De Santana BA Brazil

The aim of this study was to evaluate the accuracy of virtual three-dimensional (3D) reconstructions of human dry mandibles, produced from two segmentation protocols ("outline only" and "all-boundary lines"). Twenty virtual three-dimensional (3D) images were built from computed tomography exam (CT) of 10 dry mandibles, in which linear measurements between anatomical landmarks were obtained and compared to an error probability of 5 %. The results showed no statistically significant difference among the dry mandibles and the virtual 3D reconstructions produced from segmentation protocols tested (p = 0,24). During the designing of a virtual 3D reconstruction, both "outline only" and "all-boundary lines" segmentation protocols can be used. Virtual processing of CT images is the most complex stage during the manufacture of the biomodel. Establishing a better protocol during this phase allows the construction of a biomodel with characteristics that are closer to the original anatomical structures. This is essential to ensure a correct preoperative planning and a suitable treatment.

关键词： X-ray computed tomography computer-assisted image processing Three-dimensional imaging Rapid prototyping

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Two-dimensional sectioned images and three-dimensional surface models for learning the anatomy of the female pelvis

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ANATOMICAL SCIENCES EDUCATION 2013年第5期6卷 316-323页

作者： Shin, Dong Sun Jang, Hae Gwon Hwang, Sung Bae Har, Dong-Hwan Moon, Young Lae Chung, Min Suk Ajou Univ Dept Anat Sch Med Suwon 441749 South Korea Ajou Univ Grad Sch Informat & Commun Suwon 441749 South Korea Kyungbuk Coll Dept Phys Therapy Youngju South Korea Chung Ang Univ Grad Sch Adv Imaging Sci Multimedia & Film Seoul South Korea Chosun Univ Hosp Dept Orthoped Kwangju South Korea

In the Visible Korean project, serially sectioned images of the pelvis were made from a female cadaver. Outlines of significant structures in the sectioned images were drawn and stacked to build surface models. To improve the accessibility and informational content of these data, a five-step process was designed and implemented. First, 154 pelvic structures were outlined with additional surface reconstruction to prepare the image data. Second, the sectioned and outlined images (in a browsing software) as well as the surface models (in a PDF file) were placed on the Visible Korean homepage in a readily-accessible format. Third, all image data were visualized with interactive elements to stimulate creative learning. Fourth, two-dimensional (2D) images and three-dimensional (3D) models were superimposed on one another to provide context and spatial information for students viewing these data. Fifth, images were designed such that structure names would be shown when the mouse pointer hovered over the 2D images or the 3D models. The state-of-the-art sectioned images, outlined images, and surface models, arranged and systematized as described in this study, will aid students in understanding the anatomy of female pelvis. The graphic data accompanied by corresponding magnetic resonance images and computed tomographs are expected to promote the production of 3D simulators for clinical practice. Anat Sci Educ 6: 316-323. (c) 2013 American Association of Anatomists.

关键词： anatomic models computer-assisted image processing female pelvis three-dimensional imaging user-computer interface visible human projects

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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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New technology in dietary assessment: a review of digital methods in improving food record accuracy

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PROCEEDINGS OF THE NUTRITION SOCIETY 2013年第1期72卷 70-76页

作者： Stumbo, Phyllis J. Univ Iowa Inst Clin & Translat Sci Iowa City IA 52242 USA

Methods for conducting dietary assessment in the United States date back to the early twentieth century. Methods of assessment encompassed dietary records, written and spoken dietary recalls, FFQ using pencil and paper and more recently computer and internet applications. Emerging innovations involve camera and mobile telephone technology to capture food and meal images. This paper describes six projects sponsored by the United States National Institutes of Health that use digital methods to improve food records and two mobile phone applications using crowdsourcing. The techniques under development show promise for improving accuracy of food records.

关键词： Dietary assessment Dietary record Mobile telephone computer-assisted image processing Epidemiological methods

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Study of edge detection task in dental panoramic radiographs

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DENTOMAXILLOFACIAL RADIOLOGY 2013年第7期42卷 20120391-20120391页

作者： Grafova, L. Kasparova, M. Kakawand, S. Prochazka, A. Dostalova, T. Inst Chem Technol Fac Chem Engn Dept Comp & Control Engn CR-16628 Prague 6 Czech Republic Charles Univ Prague Dept Stomatol Fac Med 2 Prague Czech Republic

The purpose of this study is (1) to introduce a new approach for edge detection in orthopantograms (OPGs) and an improved automatic parameter selector for common edge detectors, (2) to present a comparison between our novel approach with common edge detectors and (3) to provide faster outputs without compromising quality. A new approach for edge detection based on statistical measures was introduced: (1) a set of N edge detection results is calculated from a given input image and a selected type of edge detector, (2) N correspondence maps are constructed from N edge detection results, (3) probabilities and average probabilities are computed, (4) an overall correspondence is evaluated for each correspondence map and (5) the correspondence map providing the best overall correspondence is taken as the result of edge detection procedure. A comparison with common edge detectors (the Roberts, Prewitt, Sobel, Laplacian of the Gaussian and Canny methods) with various parameter settings (304 combinations for each test image) was carried out. The methods were assessed objectively [edge mismatch error (EME), modified Hausdorff distance (MHD) and principal component analysis] and subjectively by experts in dentistry and based on time demands. The suitability of the new approach for edge detection in OPGs was confirmed by experts. The current conventional methods in edge detection in OPGs are inadequate (none of the tested methods reach an EME value or MHD value below 0.1). Our proposed approach for edge detection shows promising potential for its implementation in clinical dentistry. It enhances the accuracy of OPG interpretation and advances diagnosis and treatment planning.

关键词： panoramic radiography medical imaging computer-assisted image processing

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A Statistical Cerebroarterial Atlas Derived from 700 MRA Datasets

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METHODS OF INFORMATION IN MEDICINE 2013年第6期52卷 467-474页

作者： Forkert, N. D. Fiehler, J. Suniaga, S. Wersching, H. Knecht, S. Kemmling, A. Univ Med Ctr Hamburg Eppendorf Dept Diagnost & Intervent Neuroradiol D-20246 Hamburg Germany Univ Med Ctr Hamburg Eppendorf Dept Computat Neuroscience D-20246 Hamburg Germany Univ Munster Dept Epidemiol & Social Med Munster Germany Univ Munster Dept Neurol D-48149 Munster Germany Univ Munster Dept Clin Radiol Munster Germany

Objectives: The cerebroarterial system is a complex network of arteries that supply the brain cells with vitally important nutrients and oxygen. The inter-individual differences of the cerebral arteries, especially at a finer level, are still not understood sufficiently. The aim of this work is to present a statistical cerebroarterial atlas that can be used to overcome this problem. Methods: Overall, 700 Time-of-Flight (TOF) magnetic resonance angiography (MRA) datasets of healthy subjects were used for atlas generation. Therefore, the cerebral arteries were automatically segmented in each dataset and used for a quantification of the;vessel diameters. After this, each TOF MRA dataset as well as the corresponding vessel segmentation and vessel diameter dataset were registered to the MM brain atlas. Finally, the registered datasets were used to calculate a statistical cerebroarterial atlas that incorporates information about the average TOF intensity, probability for a vessel occurrence and mean vessel diameter for each voxel. Results: Visual analysis revealed that arteries with a diameter as small as 0.5 mm are well represented in the atlas with quantitative values that are within range of anatomical reference values. Moreover, a highly significant strong positive correlation between the vessel diameter and occurrence probability was found. Furthermore, it was shown that an intensity-based automatic segmentation of cerebral vessels can be considerable improved by incorporating the atlas information leading to results within the range of the inter-observer agreement. Conclusion: The presented cerebroarterial atlas seems useful for improving the understanding about normal variations of cerebral arteries, initialization of cerebrovascular segmentation methods and may even lay the foundation for a reliable quantification of subtle morphological vascular changes.

关键词： Magnetic resonance imaging angiography arteries statistical atlas computer-assisted image processing

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Research on focal nodular hyperplasia with MSCT and postprocessing

Research on focal nodular hyperplasia with MSCT and postproc...

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第九届中国肿瘤微创治疗学术大会

作者： Yuan-Jian Liu Wei-Jun Fan Zhi-Dong Yuan Peng-Cheng Liu Chun-Rong Wang Wei-Qiang Yan Su-Mei Wang Jun-Hui Chen Zheng Liu Imaging Center Peking University Shenzhen Hospital State Key Laboratory of Oncology in Southern China Imaging and Interventional CenterCancer CenterSun Yat-sen University

＜正＞AIM:To investigate and evaluate the pathological features and diagnostic value of focal nodular hyperplasia （FNH） with multi-section spiral computed tomography （MSCT） and postprocessing. METHODS:A total of 25 patients with FNH who had undergone MSCT and postprocessing were included in the *** patients had been pathologically or clinically confirmed with FNH.A number of 75 cases of hepatic carcinomas,hemangiomas and adenomas were randomly selected at a same period for a comparative study. RESULTS:There was a single focus in 22 cases and multiple foci in 3 *** the plain scan,17 lesions showed hypodensity,7 isodensity and 4 hyperdensity （the case with fatty liver）.With contrast,28 lesions were enhanced evenly or in the nodules in the arterial phase;13 lesions still showed hyperdensity,11 lesions isodensity and 4 lesions hypodensity in the parenchymatous phase;in the delayed phase only 5 lesions showed hyperdensity but 9 lesions showed isodensity or slight hypodensity and 14 lesions showed *** lesions of 28 had central asteroid *** feeding arteries in postprocessing were seen in 24 lesions,and were integrated into the parenchymatous lesions with a gradual and smooth *** the contrary,there were no artery penetrated into the lesion found in any of comparative hepatic tumors. CONCLUSION:Doctors could make a correct diagnosis and differentiation of FNH on evaluation of the characteristic appearance on MSCT with postprocessing.

关键词： Angiography computer-assisted image processing Focal nodular hyperplasia Liver diseases X-ray Computed tomography

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Enabling user-guided segmentation and tracking of surface-labeled cells in time-lapse image sets of living tissues

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CYTOMETRY PART A 2012年第5期81A卷 409-418页

作者： Mashburn, David N. Lynch, Holley E. Ma, Xiaoyan Hutson, M. Shane Vanderbilt Univ Dept Phys & Astron Nashville TN 37235 USA Vanderbilt Univ Dept Biol Sci Nashville TN 37235 USA Vanderbilt Univ Vanderbilt Inst Integrat Biosyst Res & Educ Nashville TN 37235 USA

To study the process of morphogenesis, one often needs to collect and segment time-lapse images of living tissues to accurately track changing cellular morphology. This task typically involves segmenting and tracking tens to hundreds of individual cells over hundreds of image frames, a scale that would certainly benefit from automated routines;however, any automated routine would need to reliably handle a large number of sporadic, and yet typical problems (e.g., illumination inconsistency, photobleaching, rapid cell motions, and drift of focus or of cells moving through the imaging plane). Here, we present a segmentation and cell tracking approach based on the premise that users know their data bestinterpreting and using image features that are not accounted for in any a priori algorithm design. We have developed a program, SeedWater Segmenter, that combines a parameter-less and fast automated watershed algorithm with a suite of manual intervention tools that enables users with little to no specialized knowledge of image processing to efficiently segment images with near-perfect accuracy based on simple user interactions. (c) 2012 International Society for Advancement of Cytometry

关键词： image segmentation computer-assisted image processing tissue analysis confocal microscopy Drosophila embryogenesis

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Volumetric difference evaluation of registered three-dimensional pre-operative and post-operative CT dental data

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DENTOMAXILLOFACIAL RADIOLOGY 2012年第4期41卷 328-339页

作者： Economopoulos, T. L. Asvestas, P. A. Matsopoulos, G. K. Molnar, B. Windisch, P. Natl Tech Univ Athens Sch Elect & Comp Engn GR-10682 Athens Greece Technol Educ Inst Athens Dept Med Instruments Technol Athens Greece Semmelweis Univ Dept Periodontol Budapest Hungary

Objective: The purpose of this study is to propose a complete methodology for automatically registering three-dimensional (3D) pre-operative and post-operative CT scan dental volumes as well as to provide a toolset for quantifying and evaluating their volumetric differences. Methods: The proposed methodology was applied to cone beam CT (CBCT) data from 20 patients in order to assess the volume of augmented bone in the alveolar region. In each case, the pre-operative and post-operative data were registered using a 3D affine-based scheme. The performance of the 3D registration algorithm was evaluated by measuring the average distance between the edges of the registered sets. The differences between the registered sets were assessed through 3D subtraction radiography. The volume of the differences was finally evaluated by defining regions of interest in each slice of the subtracted 3D data and by combining all respective slices to model the desired volume of interest. The effectiveness of the algorithm was verified by applying it to several reference standard-shaped objects with known volumes. Results: Satisfactory alignment was achieved as a low average offset of 1.483 +/- 1.558 mm was recorded between the edges of the registered sets. Moreover, the estimated volumes closely matched the volumes of the reference objects used for verification, as the recorded volume differences were less than 0.4 mm(3) in all cases. Conclusion: The proposed method allows for automatic registration of 3D CBCT data sets and the volumetric assessment of their differences in particular areas of interest. The proposed approach provides accurate volumetric measurements in three dimensions, requiring minimal user interaction. Dentomaxillofacial Radiology (2012) 41, 328-339. doi: 10.1259/dmfr/94040044

关键词： computer-assisted image processing digital subtraction radiography volumetric computed tomography alveolar ridge augmentation

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computerized Photogrammetry Used to Calculate the Brow Position Index

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AESTHETIC PLASTIC SURGERY 2012年第5期36卷 1047-1051页

作者： Naif-de-Andrade, Naif Thadeu Hochman, Bernardo Naif-de-Andrade, Camila Zirlis Ferreira, Lydia Masako Univ Fed Sao Paulo UNIFESP Div Plast Surg BR-04024900 Sao Paulo Brazil Univ Sao Paulo Gen Hosp Ribeirao Preto Sch Med Ribeirao Preto SP Brazil

Background The orbital region is of vital importance to facial expression. Brow ptosis, besides having an impact on facial harmony, is a sign of aging. Various surgical techniques have been developed to increase the efficacy of brow-lift surgery. However, no consensus method exists for an objective measurement of the eyebrow position due to the curvature of the face. Therefore, this study aimed to establish a method for measuring the eyebrow position using computerized photogrammetry. Methods For this study, 20 orbital regions of 10 volunteers were measured by direct anthropometry using a digital caliper and by indirect anthropometry (computerized photogrammetry) using standardized digital photographs. Lines, points, and distances were defined based on the position of the anthropometric landmarks endocanthion and exocanthion and then used to calculate the brow position index (BPI). Statistical analysis was performed using Student's t test with a significance level of 5 %. Results The BPI values obtained by computerized photogrammetric measurements did not differ significantly from those obtained by direct anthropometric measurements (p > 0.05). The mean BPI was 84.89 +/- A 10.30 for the computerized photogrammetric measurements and 85.27 +/- A 10.67 for the direct anthropometric measurements. Conclusion The BPI defined in this study and obtained by computerized photogrammetry is a reproducible and efficient method for measuring the eyebrow position.

关键词： Anthropometry computer-assisted image processing Eyebrows Photogrammetry Plastic surgery

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