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Sample records for three-dimensional ct scan

  1. Evaluation of diagnostic quality in musculoskeletal three-dimensional CT scans

    International Nuclear Information System (INIS)

    Vannier, M.W.; Hildebolt, C.F.; Gilula, L.A.; Sutherland, C.J.; Offutt, C.J.; Drebin, R.; Mantle, M.; Giordono, T.A.

    1988-01-01

    A major application of three-dimensional computed tomography (CT) is in the imaging of the skeleton. Three-dimensional CT has an important role in determining the presence and extent of congenital and acquired orthopedic abnormalities. The objective of this study was to compare the diagnostic sensitivity and specificity of three-dimensional CT, planar CT, and plain radiography in the detection and characterization of orthopedic abnormalities. Three-dimensional CT scan reconstructions were obtained by two methods, surface reconstruction and volumetric techniques. Seventy patients were imaged with CT, three-dimensional CT, and plain radiography. The consensus opinion of experts with access to all images plus clinical history, surgical findings, and follow-up findings were taken as truth. Expert radiologists read these cases in a blinded fashion. The results were compared using receiver operating characteristic (ROC) analysis. The diagnostic value of each three-dimensional reconstruction method and the parameters used to perform the reconstructions were evaluated

  2. Three-dimensional-CT imaging of colorectal disease with thin collimation helical CT scanning

    International Nuclear Information System (INIS)

    Ogura, Toshihiro; Koizumi, Koichi; Sakai, Tatsuya; Kai, Shunkichi; Takatsu, Kazuaki; Maruyama, Masakazu

    1998-01-01

    We have conducted research on three-dimensional (3D)-CT-colonoscopy with thin collimation helical CT scanning over the past three years. This has lately become a subject of special interest. 3D-CT-colonoscopy has three kinds of visualizing methods depending on the threshold setting of CT values. The first one is the virtual endoscopy method which is displayed in a similar fashion to colonoscopic images. The second one is the air image method using the air in the digestive tract as a contrast medium. The third one is the pseudo-tract method which has characteristics of both virtual endoscopy and the air image method and visualizes in a shape of the digestive tract. The image visualized by 3D-CT-colonoscopy is similar to that of conventional colonoscopy and barium enema study, which is obtained with minimal invasion to patients. Obvious advanced carcinomas were easily visualized, and even a small flat polyp measuring 5 mm in size, was able to be observed retrospectively. The characteristics of our method are that we can easily make an examination in a short time and with little dependence on expert technique. Also patients have little discomfort compared to that experienced during colonoscopy and barium enema study. Important features are as follows; long calculation time, insufficient air insufflation, fecal material in the patient''s bowel, whole abdominal scan, and spatial resolution. In the near future, a multislice CT scanner system will have ability to overcome these problems. Therefore, 3D-CT-colonoscopy might be applied in the future for first line examination as a mass screening for colorectal carcinoma. (author)

  3. Three-dimensional image analysis of the skull using variable CT scanning protocols-effect of slice thickness on measurement in the three-dimensional CT images

    Energy Technology Data Exchange (ETDEWEB)

    Jeong, Ho Gul; Kim, Kee Deog; Park, Hyok; Kim, Dong Ook; Jeong, Hai Jo; Kim, Hee Joung; Yoo, Sun Kook; Kim, Yong Oock; Park, Chang Seo [Yonsei University College of Medicine, Seoul (Korea, Republic of)

    2004-07-15

    To evaluate the quantitative accuracy of three-dimensional (3D) images by mean of comparing distance measurements on the 3D images with direct measurements of dry human skull according to slice thickness and scanning modes. An observer directly measured the distance of 21 line items between 12 orthodontic landmarks on the skull surface using a digital vernier caliper and each was repeated five times. The dry human skull was scanned with a Helical CT with various slice thickness (3, 5, 7 mm) and acquisition modes (Conventional and Helical). The same observer measured corresponding distance of the same items on reconstructed 3D images with the internal program of V-works 4.0 (Cybermed Inc., Seoul, Korea). The quantitative accuracy of distance measurements were statistically evaluated with Wilcoxons' two-sample test. 11 line items in Conventional 3 mm, 8 in Helical 3 mm, 11 in Conventional 5 mm, 10 in Helical 5 mm, 5 in Conventional 7 mm and 9 in Helical 7 mm showed no statistically significant difference. Average difference between direct measurements and measurements on 3D CT images was within 2 mm in 19 line items of Conventional 3 mm. 20 of Helical 3 mm, 15 of Conventional 5 mm, 18 of Helical 5 mm, 11 of Conventional 7 mm and 16 of Helical 7 mm. Considering image quality and patient's exposure time, scanning protocol of Helical 5 mm is recommended for 3D image analysis of the skull in CT.

  4. Clinical Application of colored three-dimensional CT (3D-CT) for brain tumors using helical scanning CT (HES-CT)

    International Nuclear Information System (INIS)

    Ogura, Yuko; Katada, Kazuhiro; Fujisawa, Kazuhisa; Imai, Fumihiro; Kawase, Tsukasa; Kamei, Yoshifumi; Kanno, Tetsuo; Takeshita, Gen; Koga, Sukehiko

    1995-01-01

    We applied colored three-dimensional CT (colored 3D-CT) images to distinguish brain tumors from the surrounding vascular and bony structures using a work station system and helical scanning CT (HES-CT). CT scanners with a slip-ring system were employed (TCT-900S and X vigor). A slice thickness of 2 mm and bed speed of 2 mm/s were used. The volume of contrast medium injected was 60 to 70 ml. Four to 8 colors were used for the tissue segmentation on the workstation system (xtension) using the data transferred from HES-CT. Tissue segmentation succeeded on the colored 3D-CT images in all 13 cases. The relationship between the tumors and the surrounding structures were easily recognized. The technique was useful to simulate operative fields, because deep structures could be visualized by cutting and drilling the colored 3D-CT volumetric data. On the basis of our findings, we suggest that colored 3D-CT images should be used as a supplementary aid for preoperative simulation. (author)

  5. Automatic three-dimensional rib centerline extraction from CT scans for enhanced visualization and anatomical context

    Science.gov (United States)

    Ramakrishnan, Sowmya; Alvino, Christopher; Grady, Leo; Kiraly, Atilla

    2011-03-01

    We present a complete automatic system to extract 3D centerlines of ribs from thoracic CT scans. Our rib centerline system determines the positional information for the rib cage consisting of extracted rib centerlines, spinal canal centerline, pairing and labeling of ribs. We show an application of this output to produce an enhanced visualization of the rib cage by the method of Kiraly et al., in which the ribs are digitally unfolded along their centerlines. The centerline extraction consists of three stages: (a) pre-trace processing for rib localization, (b) rib centerline tracing, and (c) post-trace processing to merge the rib traces. Then we classify ribs from non-ribs and determine anatomical rib labeling. Our novel centerline tracing technique uses the Random Walker algorithm to segment the structural boundary of the rib in successive 2D cross sections orthogonal to the longitudinal direction of the ribs. Then the rib centerline is progressively traced along the rib using a 3D Kalman filter. The rib centerline extraction framework was evaluated on 149 CT datasets with varying slice spacing, dose, and under a variety of reconstruction kernels. The results of the evaluation are presented. The extraction takes approximately 20 seconds on a modern radiology workstation and performs robustly even in the presence of partial volume effects or rib pathologies such as bone metastases or fractures, making the system suitable for assisting clinicians in expediting routine rib reading for oncology and trauma applications.

  6. Effect of Scanning and Reconstruction Parameters on Three Dimensional Volume and CT Value Measurement of Pulmonary Nodules: A Phantom Study

    Directory of Open Access Journals (Sweden)

    Datong SU

    2017-08-01

    Full Text Available Background and objective The computed tomography (CT follow-up of indeterminate pulmonary nodules aiming to evaluate the change of the volume and CT value is the common strategy in clinic. The CT dose needs to considered on serious CT scans in addition to the measurement accuracy. The purpose of this study is to quantify the precision of pulmonary nodule volumetric measurement and CT value measurement with various tube currents and reconstruction algorithms in a phantom study with dual-energy CT. Methods A chest phantom containing 9 artificial spherical solid nodules with known diameter (D=2.5 mm, 5 mm, 10 mm and density (-100 HU, 60 HU and 100 HU was scanned using a 64-row detector CT canner at 120 Kilovolt & various currents (10 mA, 20 mA, 50 mA, 80 mA,100 mA, 150 mA and 350 mA. Raw data were reconstructed with filtered back projection and three levels of adaptive statistical iterative reconstruction algorithm (FBP, ASIR; 30%, 50% and 80%. Automatic volumetric measurements were performed using commercially available software. The relative volume error (RVE and the absolute attenuation error (AAE between the software measures and the reference-standard were calculated. Analyses of the variance were performed to evaluate the effect of reconstruction methods, different scan parameters, nodule size and attenuation on the RPE. Results The software substantially overestimated the very small (D=2.5 mm nodule's volume [mean RVE: (100.8%±28%] and underestimated it attenuation [mean AAE: (-756±80 HU]. The mean RVEs of nodule with diameter as 5 mm and 10 mm were small [(-0.9%±1.1% vs (0.9%±1.4%], however, the mean AAEs [(-243±26 HU vs (-129±7 HU] were large. The ANOVA analysis for repeated measurements showed that different tube current and reconstruction algorithm had no significant effect on the volumetric measurements for nodules with diameter of 5 mm and 10 mm (F=5.60, P=0.10 vs F=11.13, P=0.08, but significant effects on the measurement of CT

  7. The accuracy of three-dimensional fused deposition modeling (FDM) compared with three-dimensional CT-Scans on the measurement of the mandibular ramus vertical length, gonion-menton length, and gonial angle

    Science.gov (United States)

    Savitri, I. T.; Badri, C.; Sulistyani, L. D.

    2017-08-01

    Presurgical treatment planning plays an important role in the reconstruction and correction of defects in the craniomaxillofacial region. The advance of solid freeform fabrication techniques has significantly improved the process of preparing a biomodel using computer-aided design and data from medical imaging. Many factors are implicated in the accuracy of the 3D model. To determine the accuracy of three-dimensional fused deposition modeling (FDM) models compared with three-dimensional CT scans in the measurement of the mandibular ramus vertical length, gonion-menton length, and gonial angle. Eight 3D models were produced from the CT scan data (DICOM file) of eight patients at the Department of Oral and Maxillofacial Surgery, Faculty of Dentistry, University of Indonesia, Cipto Mangunkusumo Hospital. Three measurements were done three times by two examiners. The measurements of the 3D CT scans were made using OsiriX software, while the measurements of the 3D models were made using a digital caliper and goniometry. The measurement results were then compared. There is no significant difference between the measurements of the mandibular ramus vertical length, gonion-menton length, and gonial angle using 3D CT scans and FDM 3D models. FDM 3D models are considered accurate and are acceptable for clinical applications in dental and craniomaxillofacial surgery.

  8. Panoramic three-dimensional CT imaging

    International Nuclear Information System (INIS)

    Kawamata, Akitoshi; Fujishita, Masami

    1998-01-01

    Panoramic radiography is a unique projection technique for producing a single image of both maxillary and mandibular arches and many other anatomical structures. To obtain a similar panoramic image without panoramic radiography system, a modified three-dimensional (3D) CT imaging technique was designed. A set of CT slice image data extending from the chin to the orbit was used for 3D reconstruction. The CT machine used in this study was the X-Vision (TOSHIBA, Japan). The helical scan technique was used. The slice thickness of reconstructed image was one or 1.5 mm. The occlusal plane or Frankfort horizontal (FH) plane was used as the reference line. The resultant slice image data was stored on a magnetic optical disk and then used to create panoramic 3D-CT images on a Macintosh computer systems (Power Macintosh 8600/250, Apple Computer Inc., USA). To create the panoramic 3D-CT image, the following procedure was designed: Design a curved panoramic 3D-CT imaging layer using the imaging layer and the movement of the x-ray beam in panoramic radiography system as a template; Cut this imaging layer from each slice image, then the trimmed image was transformed to a rectangular layer using the ''still image warping'' special effect in the Elastic Reality special effects system (Elastic Reality Inc., USA); Create panoramic 3D-CT image using the Voxel View (Vital Images Inc., USA) rendering system and volume rendering technique. Although the image quality was primitive, a panoramic view of maxillofacial region was obtained by this technique. (author)

  9. Three-dimensional model of the skull and the cranial bones reconstructed from CT scans designed for rapid prototyping process.

    Science.gov (United States)

    Skrzat, Janusz; Spulber, Alexandru; Walocha, Jerzy

    This paper presents the effects of building mesh models of the human skull and the cranial bones from a series of CT-scans. With the aid of computer so ware, 3D reconstructions of the whole skull and segmented cranial bones were performed and visualized by surface rendering techniques. The article briefly discusses clinical and educational applications of 3D cranial models created using stereolitographic reproduction.

  10. Three-dimensional analysis of rodent paranasal sinus cavities from X-ray computed tomography (CT) scans

    Science.gov (United States)

    Phillips, Jonathan E.; Ji, Lunan; Rivelli, Maria A.; Chapman, Richard W.; Corboz, Michel R.

    2009-01-01

    Continuous isometric microfocal X-ray computed tomography (CT) scans were acquired from an AKR/J mouse, Brown-Norway rat, and Hartley guinea pig. The anatomy and volume of the paranasal sinus cavities were defined from 2-dimensional (2-D) and 3-dimensional (3-D) CT images. Realistic 3-D images were reconstructed and used to determine the anterior maxillary, posterior maxillary, and ethmoid sinus cavity airspace volumes (mouse: 0.6, 0.7, and 0.7 mm3, rat: 8.6, 7.7, and 7.0 mm3, guinea pig: 63.5, 46.6 mm3, and no ethmoid cavity, respectively). The mouse paranasal sinus cavities are similar to the corresponding rat cavities, with a reduction in size, while the corresponding maxillary sinus cavities in the guinea pig are different in size, location, and architecture. Also, the ethmoid sinus cavity is connected by a common drainage pathway to the posterior maxillary sinus in mouse and rat while a similar ethmoid sinus was not present in the guinea pig. We conclude that paranasal sinus cavity airspace opacity (2-D) or volume (3-D) determined by micro-CT scanning may be used to conduct longitudinal studies on the patency of the maxillary sinus cavities of rodents. This represents a potentially useful endpoint for developing and testing drugs in a small animal model of sinusitis. PMID:19794893

  11. Study of three-dimensional image display by systemic CT

    International Nuclear Information System (INIS)

    Fujioka, Tadao; Ebihara, Yoshiyuki; Unei, Hiroshi; Hayashi, Masao; Shinohe, Tooru; Wada, Yuji; Sakai, Takatsugu; Kashima, Kenji; Fujita, Yoshihiro

    1989-01-01

    A head phantom for CT was scanned at 2 mm intervals from the cervix to the vertex in an attempt to obtain a three-dimensional image display of bones and facial epidermis from an ordinary axial image. Clinically, three-dimensional images were formed at eye sockets and hip joints. With the three-dimensional image using the head phantom, the entire head could be displayed at any angle. Clinically, images were obtained that could not be attained by ordinary CT scanning, such as broken bones in eye sockets and stereoscopic structure at the bottom of a cranium. The three-dimensional image display is considered to be useful in clinical diagnosis. (author)

  12. A comparative study of linear measurement of the brain and three-dimensional measurement of brain volume using CT scans

    International Nuclear Information System (INIS)

    Hamano, K.; Iwasaki, N.; Takeya, T.; Takita, H.

    1993-01-01

    Parameters of linear measurement were compared with actual brain volume to assess the significance of linear measurements as indices of atrophy in 31 neurologically normal children and 22 neurologically abnormal children. Brain volume was established by means of an image-analyzing system using contiguous CT scans. The parameters or indices estimated were: (1) the maximum transverse width of both hemispheres, (2) the maximum longitudinal length of both hemispheres, (3) the maximum frontal subarachnoid space, (4) the maximum width of the interhemispheric fissure, (5) the maximum width of the Sylvian fissure, (6) Evans' ratio, (7) the maximum width of the third ventricle, (8) the cella media index, (9) the maximum width of the fourth ventricle. In neurologically normal children, the maximum transverse width of both hemispheres, the maximum longitudinal length of both hemispheres, the maximum width of the interhemispheric fissure and the maximum width of the Sylvian fissure correlated significantly with the combined volume (CV) of both hemipheres and basal ganglia. In particular, the maximum transverse width of both hemispheres and the maximum longitudinal length of both hemispheres had a high correlation. In neurologically abnormal children the maximum transverse width of both hemispheres and the maximum width of the interhemispheric fissure were significantly correlated with the CV of both hemispheres and basal ganglia. (orig.)

  13. Three-dimensional CT of the mandible

    International Nuclear Information System (INIS)

    Zinreich, S.J.; Price, J.C.; Wang, H.; Ahn, H.S.; Kashima, H.

    1988-01-01

    Seventeen patients with mandibular oblation for facial neoplasia, primary neoplasm, and trauma were evaluated with CT and three-dimensional CT. In eight of these patients, a computerized acrylic model was generated for preoperative planning and postoperative reconstruction. The ramus and body of the mandible were reconstructed with mirror image and fusion techniques. Reconstructions of the anterior mandible were generated from models including the midface, skull based, and residual mandibular fragments. The results are preliminary; however, the authors believe that these represent a powerful new tool and a significant advance in mandibular reconstructive technique, reduced anesthesia time, and the optimized restoration of dental alignment and facial contour

  14. Three-dimensional reconstruction of CT images

    Energy Technology Data Exchange (ETDEWEB)

    Watanabe, Toshiaki; Kattoh, Keiichi; Kawakami, Genichiroh; Igami, Isao; Mariya, Yasushi; Nakamura, Yasuhiko; Saitoh, Yohko; Tamura, Koreroku; Shinozaki, Tatsuyo

    1986-09-01

    Computed tomography (CT) has the ability to provide sensitive visualization of organs and lesions. Owing to the nature of CT to be transaxial images, a structure which is greater than a certain size appears as several serial CT images. Consequently each observer must reconstruct those images into a three-dimensional (3-D) form mentally. It has been supposed to be of great use if such a 3-D form can be described as a definite figure. A new computer program has been developed which can produce 3-D figures from the profiles of organs and lesions on CT images using spline curves. The figures obtained through this method are regarded to have practical applications.

  15. A three-dimensional-weighted cone beam filtered backprojection (CB-FBP) algorithm for image reconstruction in volumetric CT-helical scanning

    International Nuclear Information System (INIS)

    Tang Xiangyang; Hsieh Jiang; Nilsen, Roy A; Dutta, Sandeep; Samsonov, Dmitry; Hagiwara, Akira

    2006-01-01

    Based on the structure of the original helical FDK algorithm, a three-dimensional (3D)-weighted cone beam filtered backprojection (CB-FBP) algorithm is proposed for image reconstruction in volumetric CT under helical source trajectory. In addition to its dependence on view and fan angles, the 3D weighting utilizes the cone angle dependency of a ray to improve reconstruction accuracy. The 3D weighting is ray-dependent and the underlying mechanism is to give a favourable weight to the ray with the smaller cone angle out of a pair of conjugate rays but an unfavourable weight to the ray with the larger cone angle out of the conjugate ray pair. The proposed 3D-weighted helical CB-FBP reconstruction algorithm is implemented in the cone-parallel geometry that can improve noise uniformity and image generation speed significantly. Under the cone-parallel geometry, the filtering is naturally carried out along the tangential direction of the helical source trajectory. By exploring the 3D weighting's dependence on cone angle, the proposed helical 3D-weighted CB-FBP reconstruction algorithm can provide significantly improved reconstruction accuracy at moderate cone angle and high helical pitches. The 3D-weighted CB-FBP algorithm is experimentally evaluated by computer-simulated phantoms and phantoms scanned by a diagnostic volumetric CT system with a detector dimension of 64 x 0.625 mm over various helical pitches. The computer simulation study shows that the 3D weighting enables the proposed algorithm to reach reconstruction accuracy comparable to that of exact CB reconstruction algorithms, such as the Katsevich algorithm, under a moderate cone angle (4 deg.) and various helical pitches. Meanwhile, the experimental evaluation using the phantoms scanned by a volumetric CT system shows that the spatial resolution along the z-direction and noise characteristics of the proposed 3D-weighted helical CB-FBP reconstruction algorithm are maintained very well in comparison to the FDK

  16. Two-and three-dimensional CT reconstruction

    International Nuclear Information System (INIS)

    Fishman, E.K.; Ney, D.R.; Magid, D.

    1990-01-01

    This paper determines the optimal imaging sequence for creating two- and three-dimensional (2D/3D) skeletal reconstructions from CT data. A cadaver femur, a bone phantom, and a surgically created fracture were scanned with varying protocols to determine the optimal protocol for creating 2D/3D images. The scanning protocols used varying section thickness (2, 4, and 8 mm) as well as scan spacing (2, 3, 4 and 8 mm). All images were reconstructed into 2D data sets with a bicubic interpolation and 3D datasets with volumetric rendering. The results were reviewed by two reviewers to determine the quality of images reconstruction

  17. Quantification of Emphysema with a Three-Dimensional Chest CT Scan: Correlation with the Visual Emphysema Scoring on Chest CT, Pulmonary Function Tests and Dyspnea Severity

    Energy Technology Data Exchange (ETDEWEB)

    Park, Hyun Jeong; Hwang, Jung Hwa [Dept. of Radiology, Soonchunhyang University Seoul Hospital, Seoul (Korea, Republic of)

    2011-09-15

    We wanted to prospectively evaluate the correlation between the quantification of emphysema using 3D CT densitometry with the visual emphysema score, pulmonary function tests (PFT) and the dyspnea score in patients with chronic obstructive pulmonary disease (COPD). Non-enhanced chest CT with 3D reconstruction was performed in 28 men with COPD (age 54-88 years). With histogram analysis, the total lung volume, mean lung density and proportion of low attenuation lung volume below predetermined thresholds were measured. The CT parameters were compared with the visual emphysema score, the PFT and the dyspnea score. A low attenuation lung volume below -950 HU was well correlated with the DLco and FEV{sub 1}/FVC. A Low attenuation lung volume below -950 HU and -930 HU was correlated with visual the emphysema score. A low attenuation lung volume below -950 HU was correlated with the dyspnea score, although the correlations between the other CT parameters and the dyspnea score were not significant. Objective quantification of emphysema using 3D CT densitometry was correlated with the visual emphysema score. A low attenuation lung volume below -950 HU was correlated with the DLco, the FEV{sub 1}/FVC and the dyspnea score.

  18. Quantification of Emphysema with a Three-Dimensional Chest CT Scan: Correlation with the Visual Emphysema Scoring on Chest CT, Pulmonary Function Tests and Dyspnea Severity

    International Nuclear Information System (INIS)

    Park, Hyun Jeong; Hwang, Jung Hwa

    2011-01-01

    We wanted to prospectively evaluate the correlation between the quantification of emphysema using 3D CT densitometry with the visual emphysema score, pulmonary function tests (PFT) and the dyspnea score in patients with chronic obstructive pulmonary disease (COPD). Non-enhanced chest CT with 3D reconstruction was performed in 28 men with COPD (age 54-88 years). With histogram analysis, the total lung volume, mean lung density and proportion of low attenuation lung volume below predetermined thresholds were measured. The CT parameters were compared with the visual emphysema score, the PFT and the dyspnea score. A low attenuation lung volume below -950 HU was well correlated with the DLco and FEV 1 /FVC. A Low attenuation lung volume below -950 HU and -930 HU was correlated with visual the emphysema score. A low attenuation lung volume below -950 HU was correlated with the dyspnea score, although the correlations between the other CT parameters and the dyspnea score were not significant. Objective quantification of emphysema using 3D CT densitometry was correlated with the visual emphysema score. A low attenuation lung volume below -950 HU was correlated with the DLco, the FEV 1 /FVC and the dyspnea score.

  19. Pulmonary sequestration: diagnosis with three dimensional reconstruction using spiral CT

    International Nuclear Information System (INIS)

    Nie Yongkang; Zhao Shaohong; Cai Zulong; Yang Li; Zhao Hong; Zhang Ailian; Huang Hui

    2003-01-01

    Objective: To evaluate the role of three dimensional (3D) reconstruction using spiral CT in the diagnosis of pulmonary sequestration. Methods: Ten patients with pulmonary sequestration were analyzed. The diagnoses were confirmed by angiography in 2 patients, by operation in 2 patients, and by CT angiography in 6 patients. All patients were examined with Philips SR 7000 or GE Lightspeed Plus scanner. CT images were transferred to a workstation and 3D reconstruction was performed. All images were reviewed and analyzed by two radiologists. Results: Among 10 patients, the pulmonary sequestration was in the right lower lobe in 1 patient and in the left lower lobe in 9 patients. Anomalous systemic arteries originated from thoracic aorta in 8 patients and from celiac artery in 2 patients. On plain CT scan, there were 4 patients with patchy opacities, 3 patients with hilar mass accompanying vascular engorgement and profusion in adjacent parenchyma, 2 patients with finger-like appendage surrounded by hyper-inflated lung, and 1 patient with lung mass-like lesion. Enhanced CT revealed anomalous systemic arteries in 9 patients and drainage vein in 7 patients. Maximum intensity projection (MIP) and curvilinear reconstruction could depict the abnormal systemic artery and drainage vein in sequestration. Surface shadow display (SSD) and volume rendering (VR) could delineate the anomalous systemic artery. Conclusion: 3D reconstruction with enhanced spiral CT can depict anomalous systemic artery and drainage vein and it is the first method of choice in diagnosing pulmonary sequestration

  20. Two- and three-dimensional CT analysis of ankle fractures

    International Nuclear Information System (INIS)

    Magid, D.; Fishman, E.K.; Ney, D.R.; Kuhlman, J.E.

    1988-01-01

    CT with coronal and sagittal reformatting (two-dimensional CT) and animated volumetric image rendering (three-dimensional CT) was used to assess ankle fractures. Partial volume limits transaxial CT in assessments of horizontally oriented structures. Two-dimensional CT, being orthogonal to the plafond, superior mortise, talar dome, and tibial epiphysis, often provides the most clinically useful images. Two-dimensional CT is most useful in characterizing potentially confusing fractures, such as Tillaux (anterior tubercle), triplane, osteochondral talar dome, or nondisplaced talar neck fractures, and it is the best study to confirm intraarticular fragments. Two-and three-dimensional CT best indicate the percentage of articular surface involvement and best demonstrate postoperative results or complications (hardware migration, residual step-off, delayed union, DJD, AVN, etc). Animated three-dimensional images are the preferred means of integrating the two-dimensional findings for surgical planning, as these images more closely simulate the clinical problem

  1. Three-Dimensional scanning transmission electron microscopy of biological specimens

    KAUST Repository

    De Jonge, Niels; Sougrat, Rachid; Northan, Brian M.; Pennycook, Stephen J.

    2010-01-01

    A three-dimensional (3D) reconstruction of the cytoskeleton and a clathrin-coated pit in mammalian cells has been achieved from a focal-series of images recorded in an aberration-corrected scanning transmission electron microscope (STEM

  2. Body CT (CAT Scan)

    Science.gov (United States)

    ... a CT scan can be reformatted in multiple planes, and can even generate three-dimensional images. These ... other medical conditions and whether you have a history of heart disease, asthma, diabetes, kidney disease or ...

  3. Application of Simulated Three Dimensional CT Image in Orthognathic Surgery

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Hyun Don; Park, Chang Seo [Dept. of Dental Radiology, College of Dentistry, Yensei University, Seoul (Korea, Republic of); Yoo, Sun Kook; Lee, Kyoung Sang [Dept. of Medical Engineering, College of Medicine, Yensei University, Seoul (Korea, Republic of)

    1998-08-15

    In orthodontics and orthognathic surgery, cephalogram has been routine practice in diagnosis and treatment evaluation of craniofacial deformity. But its inherent distortion of actual length and angles during projecting three dimensional object to two dimensional plane might cause errors in quantitative analysis of shape and size. Therefore, it is desirable that three dimensional object is diagnosed and evaluated three dimensionally and three dimensional CT image is best for three dimensional analysis. Development of clinic necessitates evaluation of result of treatment and comparison before and after surgery. It is desirable that patient that was diagnosed and planned by three dimensional computed tomography before surgery is evaluated by three dimensional computed tomography after surgery, too. But Because there is no standardized normal values in three dimension now and three dimensional Computed Tomography needs expensive equipment and because of its expenses and amount of exposure to radiation, limitations still remain to be solved in its application to routine practice. If postoperative three dimensional image is constructed by pre and postoperative lateral and postero-anterior cephalograms and preoperative three dimensional computed tomogram, pre and postoperative image will be compared and evaluated three dimensionally without three dimensional computed tomography after surgery and that will contribute to standardize normal values in three dimension. This study introduced new method that computer-simulated three dimensional image was constructed by preoperative three dimensional computed tomogram and pre and postoperative lateral and postero-anterior cephalograms, and for validation of new method, in four cases of dry skull that position of mandible was displaced and four patients of orthognathic surgery, computer-simulated three dimensional image and actual postoperative three dimensional image were compared. The results were as follows. 1. In four cases of

  4. Application of Simulated Three Dimensional CT Image in Orthognathic Surgery

    International Nuclear Information System (INIS)

    Kim, Hyun Don; Park, Chang Seo; Yoo, Sun Kook; Lee, Kyoung Sang

    1998-01-01

    In orthodontics and orthognathic surgery, cephalogram has been routine practice in diagnosis and treatment evaluation of craniofacial deformity. But its inherent distortion of actual length and angles during projecting three dimensional object to two dimensional plane might cause errors in quantitative analysis of shape and size. Therefore, it is desirable that three dimensional object is diagnosed and evaluated three dimensionally and three dimensional CT image is best for three dimensional analysis. Development of clinic necessitates evaluation of result of treatment and comparison before and after surgery. It is desirable that patient that was diagnosed and planned by three dimensional computed tomography before surgery is evaluated by three dimensional computed tomography after surgery, too. But Because there is no standardized normal values in three dimension now and three dimensional Computed Tomography needs expensive equipment and because of its expenses and amount of exposure to radiation, limitations still remain to be solved in its application to routine practice. If postoperative three dimensional image is constructed by pre and postoperative lateral and postero-anterior cephalograms and preoperative three dimensional computed tomogram, pre and postoperative image will be compared and evaluated three dimensionally without three dimensional computed tomography after surgery and that will contribute to standardize normal values in three dimension. This study introduced new method that computer-simulated three dimensional image was constructed by preoperative three dimensional computed tomogram and pre and postoperative lateral and postero-anterior cephalograms, and for validation of new method, in four cases of dry skull that position of mandible was displaced and four patients of orthognathic surgery, computer-simulated three dimensional image and actual postoperative three dimensional image were compared. The results were as follows. 1. In four cases of

  5. Three-dimensional CT of the pediatric spine

    International Nuclear Information System (INIS)

    Starshak, R.J.; Crawford, C.R.; Waisman, R.C.; Sty, J.R.

    1987-01-01

    CT of the spine has been shown to be useful in evaluating congenital, neoplastic, inflammatory, and traumatic lesions. Any portion of the neural arch may be involved by these disease processes. However, the complex nature of the spinal column can make evaluation of these abnormalities difficult on axial CT. This is especially true if the spine is distorted by scoliosis, kyphosis, or lordosis. The principal advantage of three-dimensional CT is its ability to display the surface relationships of complicated objects. The complexity of the spinal axis makes it ideal for study with three-dimensional CT. This presentation illustrates the advantages and drawbacks of three-dimensional CT in spinal abnormalities in children

  6. Three-dimensional spiral CT for neurosurgical planning.

    Science.gov (United States)

    Klein, H M; Bertalanffy, H; Mayfrank, L; Thron, A; Günther, R W; Gilsbach, J M

    1994-08-01

    We carried out 22 examinations to determine the value of three-dimensional (3D) volumetric CT (spiral CT) for planning neurosurgical procedures. All examinations were carried out on a of the first generation spiral CT. A tube model was used to investigate the influence of different parameter settings. Bolus injection of nonionic contrast medium was used when vessels or strongly enhancing tumours were to be delineated. 3D reconstructions were carried out using the integrated 3D software of the scanner. We found a table feed of 3 mm/s with a slice thickness of 2 mm and an increment of 1 mm to be suitable for most purposes. For larger regions of interest a table feed of 5 mm was the maximum which could be used without blurring of the 3D images. Particular advantages of 3D reconstructed spiral scanning were seen in the planning of approaches to the lower clivus, acquired or congenital bony abnormalities and when the relationship between vessels, tumour and bone was important.

  7. Application of CT three-dimensional reconstruction in elbow injury

    International Nuclear Information System (INIS)

    Liang Wenhua; Qian Li

    2009-01-01

    Objective: To investigate the application of multi-slice spiral CT in fracture of elbow, and to study the value of different methods of the reconstruction. Methods: Thin line cross-section spiral CT scan was carried out in 13 cases with elbow injury, three-dimensional reconstruction was completed later. Several reconstructed image quality to display f the elbow fracture and dislocation were analyzed and compared. Results: 13 cases (17) elbow trauma included humeral media epicondyle fracture, humeral external epicondyle fracture, intercondylar fracture, olecranal fracture and radial head fracture. Among them, X-ray film showed negative in three sites, showed suspect fractures in 2 cases, and only showed single fracture in 2 cases. MPR reconstruction image could not only identify the diagnosis of fracture, but also provide further multi-angle display on fracture line and the extent of articular surface involvement. Surface reconstruction technology could exclude the impact of passive elbow flexion and display elbow injury more intuitively. Conclusion The elbow fracture dislocation could be showed clearly in multi-slice spiral CT, especially for complex fractures, with unmatched advantages compared to X-ray for clinical diagnosis and treatment determination. (authors)

  8. Three-dimensional spiral CT for neurosurgical planning

    International Nuclear Information System (INIS)

    Klein, H.M.; Bertalanffy, H.; Mayfrank, L.; Thron, A.; Guenther, R.W.; Gilsbach, J.M.

    1994-01-01

    We carried out 22 examinations to determine the value of three-dimensional (3D) volumetric CT (spiral CT) for planning neurosurgical procedures. All examinations were carried out on a of the first generation spiral CT. A tube model was used to investigate the influence of different parameter settings. Bolus injection of nonionic contrast medium was used when vessels or strongly enhancing tumours were to be delineated. 3D reconstructions were carried out using the integrated 3D software of the scanner. We found a table feed of 3 mm/s with a slice thickness of 2 mm and an increment of 1 mm to be suitable for most purposes. For larger regions of interest a table feed of 5 mm was the maximum which could be used without blurring of the 3D images. Particular advantages of 3D reconstructed spiral scanning were seen in the planning of approaches to the lower clivus, acquired or congenital bony abnormalities and when the relationship between vessels, tumour and bone was important. (orig.)

  9. Three-dimensional CT of the pediatric spine

    International Nuclear Information System (INIS)

    Starshak, R.J.; Crawford, C.R.; Waisman, R.C.; Sty, J.R.

    1987-01-01

    CT of the spine has been shown to be useful in evaluating congenital, neoplastic, inflammatory, and traumatic lesions. Any portion of the neural arch may be involved by these disease processes. The complex nature of the spinal column can make evaluation of these abnormalities difficult on axial CT. This is especially true if the spine is distorted by scoliosis, kyphosis, or lordosis. This exhibit illustrates the advantages and drawbacks of three-dimensional CT reconstructed images of spinal abnormalities in children

  10. Application of three-dimensional CT reconstruction cranioplasty

    International Nuclear Information System (INIS)

    Yan Shuli; Yun Yongxing; Wan Kunming; Qiu Jian

    2011-01-01

    Objective: To study the application of three-dimensional CT reconstruction in cranioplasty. Methods: 46 patients with skull defect were divided into two group. One group underwent CT examination and three-dimensional reconstruction, and then the Titanium nets production company manufactured corresponding titanium meshes were shaped those data before the operation. The other group received traditional operation in which titanium meshes were shaped during operation. The average time of operation were compared. Results: The average time of operation of the first group is 86.6±13.6 mins, and that of the second group is 115±15.0 mins. The difference of average operation time between the two groups was statistically significant. Conclusion: Three-dimensional CT reconstruction techniques contribute to shorten the average operation time, reduce the intensity of neurosurgeon's work and the patien's risk. (authors)

  11. Integrated three-dimensional display of MR, CT, and PET images of the brain

    International Nuclear Information System (INIS)

    Levin, D.N.; Herrmann, A.; Chen, G.T.Y.

    1988-01-01

    MR, CT, and PET studies depict complementary aspects of brain anatomy and function. The authors' own image-processing software and a Pixar image computer were used to create three-dimensional models of brain soft tissues from MR images, of the skull and calcifications from CT scans, and of brain metabolism from PET images. An image correlation program, based on surface fitting, was used for retrospective registration and merging of these three-dimensional models. The results are demonstrated in a video clip showing how the operator may rotate and perform electronic surgery on the integrated, multimodality three-dimensional model of each patient's brain

  12. Three dimensional CT imaging of ossicular chain: a preliminary study

    International Nuclear Information System (INIS)

    Hu Chunhong; Zhong Shenbin; Fu Yindi; Zhu Wei; Wang Xueyuan; Chen Jianhua; Ding Yi

    2001-01-01

    Objective: To analysis the features of normal and abnormal ossicular chain in three dimensional images and asses the best parameters and its usefulness in diagnosis and treatment of chronic otitis media (COM). Methods: All patients, including 43 patients with normal ears and 24 ears with COM, were examined using spiral CT with inner ear software, 1-mm slice width and 1 pitch. SSD method was used in three dimensional reconstruction and the threshold was 100-300 Hu. Results: In normal cases, Malleus, incus, stapes crura, incudomalleal joints and incudostapedial joints were displayed well, but stapes footplate unsatisfactorily. The disruption of the ossicular chain showed in three-dimensional images in cases of chronic otitis media was in accord with that seen in the operation. Conclusion: It is very important for imaging with high quality through selecting proper parameters, and three-dimensional image can provide valuable information for surgery

  13. [Three dimensional CT reconstruction system on a personal computer].

    Science.gov (United States)

    Watanabe, E; Ide, T; Teramoto, A; Mayanagi, Y

    1991-03-01

    A new computer system to produce three dimensional surface image from CT scan has been invented. Although many similar systems have been already developed and reported, they are too expensive to be set up in routine clinical services because most of these systems are based on high power mini-computer systems. According to the opinion that a practical 3D-CT system should be used in daily clinical activities using only a personal computer, we have transplanted the 3D program into a personal computer working in MS-DOS (16-bit, 12 MHz). We added to the program a routine which simulates surgical dissection on the surface image. The time required to produce the surface image ranges from 40 to 90 seconds. To facilitate the simulation, we connected a 3D system with the neuronavigator. The navigator gives the position of the surgical simulation when the surgeon places the navigator tip on the patient's head thus simulating the surgical excision before the real dissection.

  14. New possibilities of three-dimensional reconstruction of computed tomography scans

    International Nuclear Information System (INIS)

    Herman, M.; Tarjan, Z.; Pozzi-Mucelli, R.S.

    1996-01-01

    Three-dimensional (3D) computed tomography (CT) scan reconstructions provide impressive and illustrative images of various parts of the human body. Such images are reconstructed from a series of basic CT scans by dedicated software. The state of the art in 3D computed tomography is demonstrated with emphasis on the imaging of soft tissues. Examples are presented of imaging the craniofacial and maxillofacial complex, central nervous system, cardiovascular system, musculoskeletal system, gastrointestinal and urogenital systems, and respiratory system, and their potential in clinical practice is discussed. Although contributing no new essential diagnostic information against conventional CT scans, 3D scans can help in spatial orientation. 11 figs., 25 refs

  15. Three dimensional analysis of coelacanth body structure by computer graphics and X-ray CT images

    International Nuclear Information System (INIS)

    Suzuki, Naoki; Hamada, Takashi.

    1990-01-01

    Three dimensional imaging processes were applied for the structural and functional analyses of the modern coelacanth (Latimeria chalumnae). Visualization of the obtained images is performed with computer graphics on the basis of serial images by an X-ray CT scanning method. Reconstruction of three dimensional images of the body structure of coelacanth using the volume rendering and surface rendering methods provides us various information about external and internal shapes of this exquisite fish. (author)

  16. Three-dimensional quadratic modeling and quantitative evaluation of the diaphragm on a volumetric CT scan in patients with chronic obstructive pulmonary disease

    Energy Technology Data Exchange (ETDEWEB)

    Chang, Yongjun [School of Electrical Engineering, Korea Advanced Institute of Science and Technology, 291 Daehak-ro, Yuseong-gu, Daejeon 34138 (Korea, Republic of); Bae, Jangpyo [Interdisciplinary Program, Bioengineering Major, Graduate School, Seoul National University, Seoul 08826 (Korea, Republic of); Kim, Namkug, E-mail: namkugkim@gmail.com [Department of Convergence Medicine, University of Ulsan College of Medicine, 88 Olympic-ro 43-gil, Songpa-gu, Seoul 05505 (Korea, Republic of); Park, Joo-Young; Lee, Sang Min; Seo, Joon Beom [Department of Radiology, University of Ulsan College of Medicine, 88 Olympic-ro 43-gil, Songpa-gu, Seoul 05505 (Korea, Republic of)

    2016-07-15

    Purpose: In patients with chronic obstructive pulmonary disease (COPD), diaphragm function may deteriorate due to reduced muscle fiber length. Quantitative analysis of the morphology of the diaphragm is therefore important. In the authors current study, they propose a diaphragm segmentation method for COPD patients that uses volumetric chest computed tomography (CT) data, and they provide a quantitative analysis of the diaphragmatic dimensions. Methods: Volumetric CT data were obtained from 30 COPD patients and 10 normal control patients using a 16-row multidetector CT scanner (Siemens Sensation 16) with 0.75-mm collimation. Diaphragm segmentation using 3D ray projections on the lower surface of the lungs was performed to identify the draft diaphragmatic lung surface, which was modeled using quadratic 3D surface fitting and robust regression in order to minimize the effects of segmentation error and parameterize diaphragm morphology. This result was visually evaluated by an expert thoracic radiologist. To take into consideration the shape features of the diaphragm, several quantification parameters—including the shape index on the apex (SIA) (which was computed using gradient set to 0), principal curvatures on the apex on the fitted diaphragm surface (CA), the height between the apex and the base plane (H), the diaphragm lengths along the x-, y-, and z-axes (XL, YL, ZL), quadratic-fitted diaphragm lengths on the z-axis (FZL), average curvature (C), and surface area (SA)—were measured using in-house software and compared with the pulmonary function test (PFT) results. Results: The overall accuracy of the combined segmentation method was 97.22% ± 4.44% while the visual accuracy of the models for the segmented diaphragms was 95.28% ± 2.52% (mean ± SD). The quantitative parameters, including SIA, CA, H, XL, YL, ZL, FZL, C, and SA were 0.85 ± 0.05 (mm{sup −1}), 0.01 ± 0.00 (mm{sup −1}), 17.93 ± 10.78 (mm), 129.80 ± 11.66 (mm), 163.19 ± 13.45 (mm), 71

  17. CT Scan

    Science.gov (United States)

    ... disease, lung nodules and liver masses Monitor the effectiveness of certain treatments, such as cancer treatment Detect ... scan done in a hospital or an outpatient facility. CT scans are painless and, with newer machines, ...

  18. Three-dimensional volumetric display by inclined-plane scanning

    Science.gov (United States)

    Miyazaki, Daisuke; Eto, Takuma; Nishimura, Yasuhiro; Matsushita, Kenji

    2003-05-01

    A volumetric display system based on three-dimensional (3-D) scanning that uses an inclined two-dimensional (2-D) image is described. In the volumetric display system a 2-D display unit is placed obliquely in an imaging system into which a rotating mirror is inserted. When the mirror is rotated, the inclined 2-D image is moved laterally. A locus of the moving image can be observed by persistence of vision as a result of the high-speed rotation of the mirror. Inclined cross-sectional images of an object are displayed on the display unit in accordance with the position of the image plane to observe a 3-D image of the object by persistence of vision. Three-dimensional images formed by this display system satisfy all the criteria for stereoscopic vision. We constructed the volumetric display systems using a galvanometer mirror and a vector-scan display unit. In addition, we constructed a real-time 3-D measurement system based on a light section method. Measured 3-D images can be reconstructed in the 3-D display system in real time.

  19. Three-dimensional spiral CT of craniofacial malformations in children

    International Nuclear Information System (INIS)

    Binaghi, S.; Gudinchet, F.

    2000-01-01

    Objective. To assess the value of three-dimensional CT (3D CT) in the diagnosis and management of suspected paediatric craniofacial malformations. Materials and methods. Twenty-eight children (12 girls, 16 boys) with a mean age of 4 years, suffering from craniofacial or cervical malformations, underwent craniofacial spiral CT. 3D reformatting was performed using an independent workstation. Results. 3D CT allowed the preoperative evaluation of 16 patients with craniosynostosis and the post-surgical management of 2 patients. 3D CT clearly depicted malformations of the skull base involving the petrous bone in seven patients (four cases of Goldenhar-Gorlin syndrome, one case of Treacher-Collins syndrome and two cases of Crouzon's disease). Four patients with craniofacial clefts were also evaluated. Radiological findings were confirmed by the clinical and intraoperative findings in all patients that underwent surgical treatment. Movement artefacts and ''Lego effect'' related to abrupt change of cranial vault border were encountered and are discussed. Conclusions. 3D CT of the skull can safely and reliably identify paediatric craniofacial malformations involving bone, and it should be used as morphological mapping to help the surgeon in planning surgical treatment. (orig.)

  20. Three dimensional plastic model of the skull from CT images by using photocurable polymer

    International Nuclear Information System (INIS)

    Goto, Masaaki; Katsuki, Takeshi; Uchida, Yuuki; Ihara, Kouichiro; Noguchi, Nobuhiro

    1992-01-01

    Three dimensional analysis in medicine is increasingly becoming a valuable tool in preoperative planning, educating to students, and explaining to patients. Recently three dimensional reconstruction technology has been coupled with computerized resin hardening processes to create acrylic models from the three dimensional reconstruction data. We have fabricated two anatomical models of the skull by the computer controlled resin hardening device. Three dimensional data were created by the three-dimensional reformation system (TRI). As data entry and storage process, contour of bone tissue is manually drawn from each serial CT photographic image of transverse skull sections. These traces are then input to the frame memory by way of the video camera. The computer stores the X, Y coordinates of points along an outline as it is traced. A depth value into the structure, assigned to each section, provides the Z coordinate, that is, the third dimension. Wire frame image is generated by using the storage data. The final image produced by hidden surface removal and shading is displayed on a full color graphic display monitor. Anatomical resin models were generated by a photo hardening device which is controlled by a minicomputer and three dimensional reconstruction data. He-Cd laser beam (wave length: 325 nm) conducted through the fibers scans the bottom of the monometer liquid surface according to the each CT contour data. The elevator moves up after the polymerization of the liquid has been performed in one slice. This device is suitable for the creation of human anatomical structure because the branched form and hollow model can be made easily. Three dimensional resin models are more useful for simulation surgery, education, and explanation than computer aided three-dimensional images. (author)

  1. Radiation therapy treatment planning: CT, MR imaging and three-dimensional planning

    International Nuclear Information System (INIS)

    Lichter, A.S.

    1987-01-01

    The accuracy and sophistication of radiation therapy treatment planning have increased rapidly in the last decade. Currently, CT-based treatment planning is standard throughout the country. Care must be taken when CT is used for treatment planning because of clear differences between diagnostic scans and scans intended for therapeutic management. The use of CT in radiation therapy planning is discussed and illustrated. MR imaging adds another dimension to treatment planning. The ability to use MR imaging directly in treatment planning involves an additional complex set of capabilities from a treatment planning system. The ability to unwarp the geometrically distorted MR image is a first step. Three-dimensional dose calculations are important to display the dose on sagittal and acoronal sections. The ability to integrate the MR and CT images into a unified radiographic image is critical. CT and MR images are two-dimensional representations of a three-dimensional problem. Through sophisticated computer graphics techniques, radiation therapists are now able to integrate a three-dimensional image of the patient into the treatment planning process. This allows the use of noncoplanar treatment plans and a detailed analysis of tumor and normal tissue anatomy; it is the first step toward a fully conformational treatment planning system. These concepts are illustrated and future research goals outlined

  2. Three-dimensional monochromatic x-ray CT

    Science.gov (United States)

    Saito, Tsuneo; Kudo, Hiroyuki; Takeda, Tohoru; Itai, Yuji; Tokumori, Kenji; Toyofuku, Fukai; Hyodo, Kazuyuki; Ando, Masami; Nishimura, Ktsuyuki; Uyama, Chikao

    1995-08-01

    In this paper, we describe a 3D computed tomography (3D CT) using monochromatic x-rays generated by synchrotron radiation, which performs a direct reconstruction of 3D volume image of an object from its cone-beam projections. For the develpment of 3D CT, scanning orbit of x-ray source to obtain complete 3D information about an object and corresponding 3D image reconstruction algorithm are considered. Computer simulation studies demonstrate the validities of proposed scanning method and reconstruction algorithm. A prototype experimental system of 3D CT was constructed. Basic phantom examinations and specific material CT image by energy subtraction obtained in this experimental system are shown.

  3. Interactive, three dimensional, CT-based treatment planning of stereotaxic I-125 brain implants. 132

    International Nuclear Information System (INIS)

    Lulu, B.; Lewis, J.; Smith, V.; Stuart, A.

    1987-01-01

    Brain implants of I-125 seeds are done with the Brown-Roberts-Wells stereotaxic frame. The patient is CT scanned with the frame bolted to the skull. In the time between the scan and surgery, while the patient is under anesthesia, an interactive three dimensional CT-based treatment plan is performed on a VAX computer. The program is menu driven, easy to use, and easily modifiable. Device dependencies are limited to a small number of subroutines, and an array processor is used to speed dose calculations

  4. Three-Dimensional scanning transmission electron microscopy of biological specimens

    KAUST Repository

    De Jonge, Niels

    2010-01-18

    A three-dimensional (3D) reconstruction of the cytoskeleton and a clathrin-coated pit in mammalian cells has been achieved from a focal-series of images recorded in an aberration-corrected scanning transmission electron microscope (STEM). The specimen was a metallic replica of the biological structure comprising Pt nanoparticles 2-3 nm in diameter, with a high stability under electron beam radiation. The 3D dataset was processed by an automated deconvolution procedure. The lateral resolution was 1.1 nm, set by pixel size. Particles differing by only 10 nm in vertical position were identified as separate objects with greater than 20% dip in contrast between them. We refer to this value as the axial resolution of the deconvolution or reconstruction, the ability to recognize two objects, which were unresolved in the original dataset. The resolution of the reconstruction is comparable to that achieved by tilt-series transmission electron microscopy. However, the focal-series method does not require mechanical tilting and is therefore much faster. 3D STEM images were also recorded of the Golgi ribbon in conventional thin sections containing 3T3 cells with a comparable axial resolution in the deconvolved dataset. © 2010 Microscopy Society of America.

  5. Three-dimensional helical (spiral) CT angiography. Visualization of vessels in the maxillofacial regions

    International Nuclear Information System (INIS)

    Hanawa, Shigeo; Sakamoto, Hidetomo; Mori, Shin-ichiro; Kagawa, Toyohiro; Seze, Ryosuke; Ishioka, Hisakazu; Tashiro, Himiko; Ogawa, Kazuhisa; Wada, Tadako

    1998-01-01

    Authors performed the contrast helical CT for tumors on the maxillofacial regions, and reconstituted these data into the three-dimensional helical (spiral) CT angiography (CTA). Furthermore the conditions of photographing and the clinical significance of CTA were discussed. The subjects were 24 cases (including 13 of malignant tumors, 4 of benign tumors, 4 of inflammation and 3 of malformations), to which the contrast helical CT was performed transvenously. The photographing condition was set in principal to 140 kV of the tube voltage, 160 (200) mA of the tube current, 3 mm of the X-ray beam width, 3 mm/sec (pitch=1) of the turn-table moving speed. The relationship between the beam width and the pitch was determined by the phantom experiments. The scanning was carried out maximally for continuous 60 sec as the scanning time of a turn/sec. Of all cases, CTA visualized three-dimensionally vessels, but it was hard in the total carotid arteries and the internal-external carotid arteries. Authors analyzed the axial and the multiplanar reconstitution (MPR) images as the two-dimensional display, and the surface rendering (SR), the volume rendering and the maximum intensity projections (MIP) as the three-dimensional display. The axial and MPR image of the facial arteries and the lingual arteries as the branched vessels from the external carotid arteries were recognized easily. By SR, it was easily to understand the anatomical relationship among vessels, gnathic bone and cervical vertebrae, and by MIP sufficiently observe the concentration dependent calcification of the vessel walls. Three-dimensional CTA is very useful to get the three-dimensional visual information about the anatomical structures of the maxillofacial regions which is necessary for oral surgeons to plan the pre-operational strategies. (K.H.)

  6. Color-coded volume rendering for three-dimensional reconstructions of CT data

    International Nuclear Information System (INIS)

    Rieker, O.; Mildenberger, P.; Thelen, M.

    1999-01-01

    Purpose: To evaluate a technique of colored three-dimensional reconstructions without segmentation. Material and methods: Color-coded volume rendered images were reconstructed from the volume data of 25 thoracic, abdominal, musculoskeletal, and vascular helical CT scans using commercial software. The CT volume rendered voxels were encoded with color in the following manner. Opacity, hue, lightness, and chroma were assigned to each of four classes defined by CT number. Color-coded reconstructions were compared to the corresponding grey-scale coded reconstructions. Results: Color-coded volume rendering enabled realistic visualization of pathologic findings when there was sufficient difference in CT density. Segmentation was necessary in some cases to demonstrate small details in a complex volume. Conclusion: Color-coded volume rendering allowed lifelike visualisation of CT volumes without the need of segmentation in most cases. (orig.) [de

  7. Postoperative assessment of surgical results using three dimensional surface reconstruction CT (3D-CT) in a craniofacial anomaly

    International Nuclear Information System (INIS)

    Nishimura, Jiro; Sato, Kaoru; Nishimoto, Hiroshi; Tsukiyama, Takashi; Fujioka, Mutsuhisa; Akagawa, Tetsuya.

    1988-01-01

    In 1983, Michael W. Vannier and Jeffrey L. Marsh developed a computer method that reconstructs three dimensional (3D) born and soft tissue surfaces, given a high resolution CT scan-series of the facial skeleton. This method has been applied to craniofacial anomalies, basal encephaloceles, and musculoskeletal anomalies. In this study, a postoperative assessment of the craniofacial surgical results has been accomplished using this 3D-CT in 2 children with craniofacial dysmorphism. The authors discuss the advantages of this 3D-CT imaging method in the postoperative assessments of craniofacial anomalies. Results are detailed in the following listing : 1) a postoperative 3D-CT reveals the anatomical details corrected by the craniofacial surgery more precisely and stereographically than conventional radiological methods ; 2) secondary changes of the cranium after the surgery, such as bony formation in the area of the osteotomy and postoperative asymmetric deformities, are detected early by the 3D-CT imaging technique, and, 3) 3D-CT mid-sagittal and top axial views of the intracranial skull base are most useful in postoperative assessments of the surgical results. Basesd on our experience, we expect that three dimensional surface reconstructions from CT scans will become to be used widely in the postoperative assessments of the surgical results of craniofacial anomalies. (author)

  8. Synthetic display of three-dimensional CT and MPR for gastric neoplasm

    International Nuclear Information System (INIS)

    Ogura, Toshihiro; Maruyama, Masakazu

    1998-01-01

    We attempted to obtain synthesized three dimensional (3D) and MPR (Multi Planar Reconstruction) helical CT scans (3D-MPR-CT) of gastric neoplasm by using the air as a contrast medium, and we assessed the usefulness of 3D-MPR-CT gastroendoscopy in the diagnosis of gastric neoplasm. Five minutes before the scan, 20 mg Scopolamine Butylbromide (Buscopan) was injected intramuscularly to minimize gastric peristalsis. An effervescent agent (bubble-make granules) was fed to extend the stomach wall. Non-ionic contrast material (100 mL) was power injected immediately before the scan start. Axial images were obtained with an intersection gap of 5-mm, a 5-mm/sec table speed, and 1-mm reconstruction intervals. 3D-MPR-CT images were reconstructed from these images. In abdominal study, 3D-MPR-CT images enabled the visualization of neoplasm and its adjacent structures in versatile directions, including a view similar to endoscopic observation, proximal aspect of narrowing by tumor and also could get the information about invasive depth of gastric neoplasm. Reports on some clinical cases and the advantages and disadvantages of 3D-MPR-CT gastroendoscopy were discussed. (author)

  9. Three-dimensional CT imaging of soft-tissue anatomy

    International Nuclear Information System (INIS)

    Fishman, E.K.; Ney, D.R.; Magid, D.; Kuhlman, J.E.

    1988-01-01

    Three-dimensional display of computed tomographic data has been limited to skeletal structures. This was in part related to the reconstruction algorithm used, which relied on a binary classification scheme. A new algorithm, volumetric rendering with percentage classification, provides the ability to display three-dimensional images of muscle and soft tissue. A review was conducted of images in 35 cases in which muscle and/or soft tissue were part of the clinical problem. In all cases, individual muscle groups could be clearly identified and discriminated. Branching vessels in the range of 2.3 mm could be identified. Similarly, lymph nodes could be clearly defined. High-resolution three-dimensional images were found to be useful both in providing an increased understanding of complex muscle and soft tissue anatomy and in surgical planning

  10. Volume-editing tools for three-dimensional imaging of CT data

    International Nuclear Information System (INIS)

    Ney, D.R.; Fishman, E.K.

    1989-01-01

    Three-dimensional imaging of complex structures relies heavily on the ability to edit the routine CT scans to provide an optimal view of the area in question. The authors present a series of strategies for defining the volume editing tools. The authors have developed a series of editing tools that allow the operator to edit critical areas out of an image. The tools are based on a variety of imaging strategies that are implemented depending on the difficulty of separating two structures. The tools combine rectangular masking, threshold base filling, arbitrary curve-based masking, masking, threshold base filling, arbitrary curve-based masking, and object definition via edge detection

  11. [Application Progress of Three-dimensional Laser Scanning Technology in Medical Surface Mapping].

    Science.gov (United States)

    Zhang, Yonghong; Hou, He; Han, Yuchuan; Wang, Ning; Zhang, Ying; Zhu, Xianfeng; Wang, Mingshi

    2016-04-01

    The booming three-dimensional laser scanning technology can efficiently and effectively get spatial three-dimensional coordinates of the detected object surface and reconstruct the image at high speed,high precision and large capacity of information.Non-radiation,non-contact and the ability of visualization make it increasingly popular in three-dimensional surface medical mapping.This paper reviews the applications and developments of three-dimensional laser scanning technology in medical field,especially in stomatology,plastic surgery and orthopedics.Furthermore,the paper also discusses the application prospects in the future as well as the biomedical engineering problems it would encounter with.

  12. Three dimensional CT of stapes. Stapedial imagings in dry temporal bone and clinical applications

    Energy Technology Data Exchange (ETDEWEB)

    Edamatsu, Hideo; Kubota, Osamu; Yamashita, Koichi [Kanazawa Medical Univ., Ishikawa (Japan)

    1995-03-01

    This study was performed to evaluate the usefulness and limitations of three dimensional (3-D) imagings of stapes in the middle ear by high speed helical CT. One dissected human temporal bone, ten normal and diseased ears were scanned with a slice of 1.0 mm and reconstructed in a thickness of 0.2-0.5 mm. Every specimen of 3-D can be observed in any plane and from any direction. Ossicular imagings of the temporal bone in 3-D were reconstructed as if the malleus, incus and stapes were observed under microscope. The whole structure of stapes was impossible to be represented by two dimensional CT heretofore in use, but 3-D in our study showed the head, crus and foot plate of the stapes in detail. Stapedial imagings of 3-D CT in normal ears showed the same findings as those recorded in temporal bone. Preoperative diagnostic findings of ossicles in the affected ears were very useful. Especially in ossicular anomalies, 3-D CT was positive in diagnosis and its accuracies were confirmed with operative observation. For the postoperative evaluation concerning the ossicular reconstruction, i.e. TORP and PORP, 3-D CT was also important method. It could present an anatomical relation between those prosthesis and the oval window. High speed helical CT can scan an object more quickly and clearly than formerly used CT, and its biological damage for human is less than that of the others. 3-D CT can be more clearly reconstructed with helical CT than former CT. (author).

  13. Technique and value of three dimensional reconstruction of stones in the renal pelvis using spiral CT

    International Nuclear Information System (INIS)

    Fink, B.K.; Fink, U.; Pentenrieder, M.; Kohz, P.; Englmeier, H.K.; Schmeller, N.

    1994-01-01

    5 patients with staghorn calculi in the renal pelvis were examined by spiral CT. From the raw data three dimensional reconstructions of the stones were obtained. In all patients it was possible to compare the three dimensional model with the stone following performance of percutaneous lithopaxy and endoscopic removal of the fragments. In all cases the three dimensional reconstruction provided a realistic image of the stones and was of practical value for the urologist for preoperative diagnosis and intraoperative control. (orig.) [de

  14. Three-dimensional helical CT for treatment planning of breast cancer

    Energy Technology Data Exchange (ETDEWEB)

    Hiramatsu, Hideko; Enomoto, Kohji; Ikeda, Tadashi [Keio Univ., Tokyo (Japan). School of Medicine] [and others

    1999-01-01

    The role of three-dimensional (3D) helical CT in the treatment planning of breast cancer was evaluated. Of 36 patients examined, 30 had invasive ductal carcinoma, three had invasive lobular carcinoma, one had DCIS, one had DCIS with minimal invasion, and 1 had Paget`s disease. Patients were examined in the supine position. The whole breast was scanned under about 25 seconds of breath-holding using helical CT (Proceed, Yokogawa Medical Systems, or High-speed Advantage, GE Medical Systems). 3D imaging was obtained with computer assistance (Advantage Windows, GE Medical Systems). Linear and/or spotty enhancement on helical CT was considered to suggest DCIS or intraductal spread in the area surrounding the invasive cancer. Of 36 patients, 24 showed linear and/or spotty enhancement on helical CT, and 22 of those 24 patients had DCIS or intraductal spread. In contrast, 12 of 36 patients were considered to have little or no intraductal spread on helical CT, and eight of the 12 patients had little or no intraductal spread on pathological examination. The sensitivity, specificity, and accuracy rates for detecting intraductal spread on MRI were 85%, 80%, and 83%, respectively. 3D helical CT was considered useful in detecting intraductal spread and planning surgery, however, a larger study using a precise correlation with pathology is necessary. (author)

  15. Clinical assessment of hypopharyngeal and laryngeal disorders by three-dimensional multidetector-row CT. Feasibility of imaging during phonation

    International Nuclear Information System (INIS)

    Tan, Xiaotian

    2002-01-01

    The hypopharynx and larynx can adapt their structures to physiological functions. To clarify the relation between morphologic changes and the development of pharyngeal and laryngeal disorders, images of the hypopharynx and larynx were obtained by multidetector-row CT (MD-CT) during phonation and quiet breathing. The clinical usefulness of such imaging study was assessed by comparing the images taken in the two phases. The study included 23 subjects, 20 patients with a hypopharyngeal or laryngeal disorder and 3 healthy volunteers. MD-CT scanning of the hypopharynx and larynx was not influenced by breathing and body movement. The volume rendering (VR) method was useful in that three-dimensional imaging could visualize the internal structure of the hypopharynx and larynx. Thus, the volume rendering method can be regarded as a virtual three-dimensional method. The normal anatomic structure of the hypopharynx and larynx were depicted in full and three-dimensionally. The extent of hypopharyngeal and laryngeal cancer was shown clearly. Edema due to paralysis of recurrent nerve was demonstrated in full and three-dimensionally, providing for functional diagnosis. In the case of mucosal edema caused by trauma, the extent of the edema and its effect on the airway were clearly observed. These results suggest that MD-CT with three-dimensional imaging during phonation is useful in the diagnosis of hypopharyngeal and laryngeal disorders. (author)

  16. A pilot study of three dimensional color CT images of brain diseases to improve informed consent

    International Nuclear Information System (INIS)

    Tanizaki, Yoshio; Akiyama, Takenori; Hiraga, Kenji; Akaji, Kazunori

    2005-01-01

    We have described brain diseases to patients and their family using monochrome CT images. It is thought that patients have difficulties in giving their consent to our conventional explanation because their understanding of brain diseases is based on three dimensional and color images, however, standard CT images are two dimensional and gray scale images. We have been trying to use three dimensional color CT images to improve the typical patient's comprehension of brain diseases. We also try to simulate surgery using these images. Multi-slice CT accumulates precise isotropic voxel data within a half minute. These two dimensional and monochrome data are converted to three dimensional color CT images by 3D workstation. Three dimensional color CT images of each brain structures (e.g. scalp, skull, brain, ventricles and lesions) are created separately. Then, selected structures are fused together for different purposes. These images are able to rotate around any axis. Because the methods to generate three-dimensional color images have not established, we neurosurgeons must create these images. In particular, when an operation is required, the surgeon should create the images. In this paper, we demonstrate how three-dimensional color CT images can improve informed consent. (author)

  17. Three-dimensional multislice CT imaging of otitis media

    International Nuclear Information System (INIS)

    Suzuki, Miyako; Yoshikawa, Hiroshi; Hosokawa, Akira; Furukawa, Tomoyasu; Ichikawa, Ginichiro; Wada, Akihiro; Ando, Ichiro

    2002-01-01

    In recent years, the multislice CT system has come into practical use that enables table movement of half mm, resulting in a significant improvement in resolution. The use of this CT system enables to depict the entire auditory ossicles, including the stapes. 3D reconstruction was performed using helical CT data in 5 patients with chronic otitis media and 5 patients with cholesteatoma. An Aquilion Multi (Toshiba) multislice helical CT scanner and a Xtension (Toshiba) image workstation were used in this study. We demonstrated the 3D display with axial, coronal and sagittal images. Compared with the normal ears, it was necessary to set a higher threshold for the affected ears. It is important to select suitable threshold for demonstration of 3D images optimally. Bone destruction of the stapes was confirmed at surgery in 2 ears. The stapes was observed at 3D-CT imaging in other 18 ears. It was found that the 3D images of the ossicular destruction in ears with cholesteatoma were consistent with surgical findings. It is therefore concluded that 3D imaging of the middle ear using a multislice CT scanner is clinically useful. (author)

  18. Three-dimensional multislice CT imaging of otitis media

    Energy Technology Data Exchange (ETDEWEB)

    Suzuki, Miyako [Yanagibasi Hospital, Tokyo (Japan); Yoshikawa, Hiroshi; Hosokawa, Akira; Furukawa, Tomoyasu; Ichikawa, Ginichiro [Juntendo Univ., Tokyo (Japan). School of Medicine; Wada, Akihiro; Ando, Ichiro [Juntendo Univ., Chiba (Japan). Urayasu Hospital

    2002-07-01

    In recent years, the multislice CT system has come into practical use that enables table movement of half mm, resulting in a significant improvement in resolution. The use of this CT system enables to depict the entire auditory ossicles, including the stapes. 3D reconstruction was performed using helical CT data in 5 patients with chronic otitis media and 5 patients with cholesteatoma. An Aquilion Multi (Toshiba) multislice helical CT scanner and a Xtension (Toshiba) image workstation were used in this study. We demonstrated the 3D display with axial, coronal and sagittal images. Compared with the normal ears, it was necessary to set a higher threshold for the affected ears. It is important to select suitable threshold for demonstration of 3D images optimally. Bone destruction of the stapes was confirmed at surgery in 2 ears. The stapes was observed at 3D-CT imaging in other 18 ears. It was found that the 3D images of the ossicular destruction in ears with cholesteatoma were consistent with surgical findings. It is therefore concluded that 3D imaging of the middle ear using a multislice CT scanner is clinically useful. (author)

  19. Three dimensional phase imaging using a scanning optical fiber interferometer

    International Nuclear Information System (INIS)

    Walford, J.N.; Nugent, K.A.; Roberts, A.; Scholten, R.E.

    1998-01-01

    A quantitative method for measuring phase in three dimensions using a scanning optical fiber interferometer is described. By exploiting phase modulation in the reference arm, this technique is insensitive to large variations in the intensity of the field being studied, and is therefore highly suitable for measurement of phase within spatially confined optical beams. It uses only a single detector, and is not reliant on lock-in electronics. The technique is applied to the measurement of the near field of a cleaved optical fiber and shown to produce results in good agreement with theory. (authors)

  20. Three dimensional positron-CT: 3D-PET

    International Nuclear Information System (INIS)

    Ishii, K.

    2000-01-01

    Positron-CT, namely the positron emission tomograph (PET) provides us the metabolism images obtained by the administration of the drug labeled by the positron emission nuclide in the human body. For example, the carbohydrate metabolism image is obtained by the administration of glucose labelled by 18 F-radioisotopes, and it can be applied to early detection of the cancer and research of high-order function of the brain. As well as X-ray CT, the examine receives the exposure in the positron CT. 3D-PET is based on the solid measurement of γ-rays, therefore, the detection sensitivity of 3D-PET becomes very high and it is possible to drastically reduce the dose of the positron emission nuclide. Because the exposure is reduced to the utmost, the positron CT diagnosis would be possible for the child and the exposure of positron CT doctor in charge can be also reduced. This ideal functional diagnostic imaging equipment, namely, 3D-PET is introduced here. (author)

  1. Three-dimensional laser scanning technique to quantify aggregate and ballast shape properties

    CSIR Research Space (South Africa)

    Anochie-Boateng, Joseph

    2013-06-01

    Full Text Available methods towards a more accurate and automated techniques to quantify aggregate shape properties. This paper validates a new flakiness index equation using three-dimensional (3-D) laser scanning data of aggregate and ballast materials obtained from...

  2. Application status of three-dimensional CT reconstruction in hepatobiliary surgery

    Directory of Open Access Journals (Sweden)

    JIANG Chao

    2017-02-01

    Full Text Available With the development of imaging technology, three-dimensional CT reconstruction has been widely used in hepatobiliary surgery. Three-dimensional CT reconstruction can divide and reconstruct two-dimensional images into three-dimensional images and clearly show the location of lesion and its relationship with the intrahepatic bile duct system. It has an important value in the preoperative assessment of liver volume, diagnosis and treatment decision-making process, intraoperative precise operation, and postoperative individualized management, and promotes the constant development of hepatobiliary surgery and minimally invasive technology, and therefore, it holds promise for clinical application.

  3. Three-dimensional versus conventional CT in the evaluation of facial trauma

    International Nuclear Information System (INIS)

    Mayer, J.S.; Yeakley, J.W.; Kulkarni, M.V.; Wainwright, D.J.; Lee, K.F.; Harris, J.H. Jr.

    1987-01-01

    An accurate knowledge of the three-dimensional pattern of facial fractures is surgically important. This exhibit shows how this may be difficult if not impossible to obtain using axial and reconstructed CT images and how 3D CT is superior in this regard. 3D CT displays the course of anterior and lateral facial fractures and the spatial orientation of bone fragments that can be missed when using other CT techniques. 3D CT and facial CT images can be generated from a single CT examination and are complementary. Together they display posttraumatic facial anatomy better than conventional planar CT images

  4. Three-dimensional modeling and simulation of asphalt concrete mixtures based on X-ray CT microstructure images

    Directory of Open Access Journals (Sweden)

    Hainian Wang

    2014-02-01

    Full Text Available X-ray CT (computed tomography was used to scan asphalt mixture specimen to obtain high resolution continuous cross-section images and the meso-structure. According to the theory of three-dimensional (3D reconstruction, the 3D reconstruction algorithm was investigated in this paper. The key to the reconstruction technique is the acquisition of the voxel positions and the relationship between the pixel element and node. Three-dimensional numerical model of asphalt mixture specimen was created by a self-developed program. A splitting test was conducted to predict the stress distributions of the asphalt mixture and verify the rationality of the 3D model.

  5. Three-dimensional nanostructure determination from a large diffraction data set recorded using scanning electron nanodiffraction

    Directory of Open Access Journals (Sweden)

    Yifei Meng

    2016-09-01

    Full Text Available A diffraction-based technique is developed for the determination of three-dimensional nanostructures. The technique employs high-resolution and low-dose scanning electron nanodiffraction (SEND to acquire three-dimensional diffraction patterns, with the help of a special sample holder for large-angle rotation. Grains are identified in three-dimensional space based on crystal orientation and on reconstructed dark-field images from the recorded diffraction patterns. Application to a nanocrystalline TiN thin film shows that the three-dimensional morphology of columnar TiN grains of tens of nanometres in diameter can be reconstructed using an algebraic iterative algorithm under specified prior conditions, together with their crystallographic orientations. The principles can be extended to multiphase nanocrystalline materials as well. Thus, the tomographic SEND technique provides an effective and adaptive way of determining three-dimensional nanostructures.

  6. Three-dimensional visualization of CT data in medical radiology

    International Nuclear Information System (INIS)

    Rieker, O.

    2000-01-01

    3D visualisation of the liver is much too complex a task for conventional methods. Superposed structures must be suppressed, while tumours and the artery must be enhanced. A combination of volume rendering and segmentation is recommended. Virtual planning of liver resections requires a mathematical model, e.g. analysis of the vessel tree with spherical shells. The use of Windows-NT may be an advantage of the Mainz project as it permits the use of a common PC. It is expected that 3D CT imaging will bring about dramatic changes in surgery of the liver. 3D reconstructions of the liver will result in individualized, parenchyma-saving resection proposals which deviate from the idealized resection according to Couinaud. (orig.) [de

  7. Evaluation of living renal donors: accuracy of three-dimensional 16-section CT

    International Nuclear Information System (INIS)

    Rastogi, N; Sahani, D.V.; Blake, M.A.; Ko, D.C.; Mueller, P.R.

    2006-01-01

    Purpose: To retrospectively assess the sensitivity and specificity of three-dimensional (3D) 16-section computed tomography (CT) in the evaluation of vessels, pelvicalyceal system, and ureters in living renal donors, with surgical findings as the reference standard. Materials and methods: This was a HIPAA-compliant study. Institutional review board approval was obtained for the review of subjects' medical records and data analysis, with waiver of informed consent. Forty-six renal donors (18 men, 28 women; mean age, 42 years) were examined with 16-section CT. Two blinded reviewers independently studied renal vascular and urographic anatomy of each donor CT scans by fist using 3D images alone, then transverse images alone, and finally transverse and 3D data set. Image quality, degree of diagnostic confidence, and time used for review were recorded. Sensitivity and specificity were calculated. Results: For 3D images, transverse images, and transverse in conjunction with 3D data sets, the respective sensitivity and specificity of CT in evaluation of accessory arteries by reviewer 1 were 100% and 100%, 89% and 100%, and 100% and 100%, and those by reviewer 2 were 89% and 97%, 89% and 100%, and 89% and 100%; the respective sensitivity and specificity in evaluation of venous anomalies by reviewer 1 were 100% and 98%, 100% and 98%, and 100% and 98%, and those by reviewer 2 were 100% and 98%, 100% and 95%, and 100% and 98%. For focused comprehensive assessment of renal donors with 3D scans alone, a reviewer on average (average of reviewers 1 and 2) used 2.4 minutes per scan, demonstrated full confidence in 93%, and rated the quality as excellent in 76%. Conclusion: For focused assessment of renal vascular and urographic anatomy, review of 3D data set alone provides high sensitivity and specificity with regard to findings seen at surgery. (author)

  8. Evaluation of living renal donors: accuracy of three-dimensional 16-section CT

    Energy Technology Data Exchange (ETDEWEB)

    Rastogi, N; Sahani, D.V.; Blake, M.A.; Ko, D.C.; Mueller, P.R. [Massachusetts General Hospital, Boston, MA (United States). Dept. of Radiology

    2006-07-15

    Purpose: To retrospectively assess the sensitivity and specificity of three-dimensional (3D) 16-section computed tomography (CT) in the evaluation of vessels, pelvicalyceal system, and ureters in living renal donors, with surgical findings as the reference standard. Materials and methods: This was a HIPAA-compliant study. Institutional review board approval was obtained for the review of subjects' medical records and data analysis, with waiver of informed consent. Forty-six renal donors (18 men, 28 women; mean age, 42 years) were examined with 16-section CT. Two blinded reviewers independently studied renal vascular and urographic anatomy of each donor CT scans by fist using 3D images alone, then transverse images alone, and finally transverse and 3D data set. Image quality, degree of diagnostic confidence, and time used for review were recorded. Sensitivity and specificity were calculated. Results: For 3D images, transverse images, and transverse in conjunction with 3D data sets, the respective sensitivity and specificity of CT in evaluation of accessory arteries by reviewer 1 were 100% and 100%, 89% and 100%, and 100% and 100%, and those by reviewer 2 were 89% and 97%, 89% and 100%, and 89% and 100%; the respective sensitivity and specificity in evaluation of venous anomalies by reviewer 1 were 100% and 98%, 100% and 98%, and 100% and 98%, and those by reviewer 2 were 100% and 98%, 100% and 95%, and 100% and 98%. For focused comprehensive assessment of renal donors with 3D scans alone, a reviewer on average (average of reviewers 1 and 2) used 2.4 minutes per scan, demonstrated full confidence in 93%, and rated the quality as excellent in 76%. Conclusion: For focused assessment of renal vascular and urographic anatomy, review of 3D data set alone provides high sensitivity and specificity with regard to findings seen at surgery. (author)

  9. Three-dimensional contrasted visualization of pancreas in rats using clinical MRI and CT scanners.

    Science.gov (United States)

    Yin, Ting; Coudyzer, Walter; Peeters, Ronald; Liu, Yewei; Cona, Marlein Miranda; Feng, Yuanbo; Xia, Qian; Yu, Jie; Jiang, Yansheng; Dymarkowski, Steven; Huang, Gang; Chen, Feng; Oyen, Raymond; Ni, Yicheng

    2015-01-01

    The purpose of this work was to visualize the pancreas in post-mortem rats with local contrast medium infusion by three-dimensional (3D) magnetic resonance imaging (MRI) and computed tomography (CT) using clinical imagers. A total of 16 Sprague Dawley rats of about 300 g were used for the pancreas visualization. Following the baseline imaging, a mixed contrast medium dye called GadoIodo-EB containing optimized concentrations of Gd-DOTA, iomeprol and Evens blue was infused into the distally obstructed common bile duct (CBD) for post-contrast imaging with 3.0 T MRI and 128-slice CT scanners. Images were post-processed with the MeVisLab software package. MRI findings were co-registered with CT scans and validated with histomorphology, with relative contrast ratios quantified. Without contrast enhancement, the pancreas was indiscernible. After infusion of GadoIodo-EB solution, only the pancreatic region became outstandingly visible, as shown by 3D rendering MRI and CT and proven by colored dissection and histological examinations. The measured volume of the pancreas averaged 1.12 ± 0.04 cm(3) after standardization. Relative contrast ratios were 93.28 ± 34.61% and 26.45 ± 5.29% for MRI and CT respectively. We have developed a multifunctional contrast medium dye to help clearly visualize and delineate rat pancreas in situ using clinical MRI and CT scanners. The topographic landmarks thus created with 3D demonstration may help to provide guidelines for the next in vivo pancreatic MRI research in rodents. Copyright © 2015 John Wiley & Sons, Ltd.

  10. Three-dimensional CT endoscopic images of the larynx. Clinical application of helical CT

    International Nuclear Information System (INIS)

    Yumoto, Eiji; Sanuki, Tetsuji; Yasuhara, Yoshifumi; Ochi, Takashi

    1998-01-01

    Twenty-seven patients with several laryngeal ailments underwent helical computed tomography (CT) on 37 occasions. Ten of these 27 patients suffered from unilateral vocal fold paralysis (UVFP). Three-dimensional (3D) images of the laryngeal lumen viewed from various angles were produced for all sets of CT volumetric data, except for three which contained excessive motion artifacts. The present paper examined whether 3D endoscopic images could offer useful diagnostic and therapeutic information about UVFP. The 3D endoscopic images viewed from the tracheal side and the hemilaryngeal images viewed from the opposite side could delineate the vocal folds, ventricular fold and ventricle three-dimensionally. Atrophy and hypotonic changes to the vocal fold and expansion of the ventricle on the affected side were clearly shown. The 3D endoscopic images accurately showed the phonosurgical effects on the laryngeal structures. The 3D endoscopic images could be produced even when the vocal folds could not be observed with conventional endoscopy due to their overadduction. Multiplanar reconstruction (MPR) images in the coronal plane were reconstructed at a right angle to the glottic axis when the whole larynx was deviated. In addition, coronal MPR images showed a better resolution among the different layers of the vocal fold soft tissue than X-ray tomography. In conclusion, 3D endoscopic images combined with coronal MPR images can provide useful diagnostic an therapeutic information about UVFP, although motion artifacts may occur. (author)

  11. Head CT scan

    Science.gov (United States)

    ... scan - orbits; CT scan - sinuses; Computed tomography - cranial; CAT scan - brain ... head size in children Changes in thinking or behavior Fainting Headache, when you have certain other signs ...

  12. Development of Scanning-Imaging X-Ray Microscope for Quantitative Three-Dimensional Phase Contrast Microimaging

    International Nuclear Information System (INIS)

    Takeuchi, Akihisa; Suzuki, Yoshio; Uesugi, Kentaro

    2013-01-01

    A novel x-ray microscope system has been developed for the purpose of quantitative and sensitive three-dimensional (3D) phase-contrast x-ray microimaging. The optical system is a hybrid that consists of a scanning microscope optics with a one-dimensional (1D) focusing (line-focusing) device and an imaging microscope optics with a 1D objective. These two optics are orthogonally arranged regarding their common optical axis. Each is used for forming each dimension of two-dimensional (2D) image. The same data acquisition process as that of the scanning microscope system enables quantitative and sensitive x-ray imaging such as phase contrast and absorption contrast. Because a 2D image is measured with only 1D translation scan, much shorter measurement time than that of conventional scanning optics has been realized. By combining a computed tomography (CT) technique, some 3D CT application examples are demonstrated

  13. Postoperative follow-up study of craniosynostosis using three-dimensional surface reconstruction CT (3D-CT)

    Energy Technology Data Exchange (ETDEWEB)

    Nishimoto, Hiroshi; Tsukiyama, Takashi; Nishimura, Jiro; Fujioka, Mutsuhisa; Tsubokawa, Takashi.

    1988-12-01

    In 1983, Michael W. Vannier and Jeffrey L. Marsh developed a computer method that reconstructs three-dimensional images from high-resolution CT-scan series of the facial skeleton. This method has been applied to craniofacial anomalies, basal encephalocele, and other skeletal pathologies. In this study, the postoperative assessment of craniofacial surgical results has been accomplished using 3D-CT techniques in craniosynostosis. The results are as follows: (1) Postoperative 3D-CTs reveal the bony anatomical details corrected by the craniofacial surgery more precisely and more stereographically than do conventional radiological techniques. (2) Secondary changes in the cranium after the surgery, such as reossification at the area of osteotomies or postoperative asymmetric skull deformities, are more early detected by the 3D-CT imaging technique than by a craniogram. (3) In 3D-CT images, internal views of the skull, such mid-sagittal, rear internal, or top axial views of the intracranial skull base, are most useful in postoperative assessments of the surgical results and of postoperative secondary changes in the cranium. Based on our experience, we expect that 3D-CT imaging techniques will become more important in the management of craniosynostosis.

  14. Postoperative follow-up study of craniosynostosis using three-dimensional surface reconstruction CT (3D-CT)

    International Nuclear Information System (INIS)

    Nishimoto, Hiroshi; Tsukiyama, Takashi; Nishimura, Jiro; Fujioka, Mutsuhisa; Tsubokawa, Takashi.

    1988-01-01

    In 1983, Michael W. Vannier and Jeffrey L. Marsh developed a computer method that reconstructs three-dimensional images from high-resolution CT-scan series of the facial skeleton. This method has been applied to craniofacial anomalies, basal encephalocele, and other skeletal pathologies. In this study, the postoperative assessment of craniofacial surgical results has been accomplished using 3D-CT techniques in craniosynostosis. The results are as follows: 1) Postoperative 3D-CTs reveal the bony anatomical details corrected by the craniofacial surgery more precisely and more stereographically than do conventional radiological techniques. 2) Secondary changes in the cranium after the surgery, such as reossification at the area of osteotomies or postoperative asymmetric skull deformities, are more early detected by the 3D-CT imaging technique than by a craniogram. 3) In 3D-CT images, internal views of the skull, such mid-sagittal, rear internal, or top axial views of the intracranial skull base, are most useful in postoperative assessments of the surgical results and of postoperative secondary changes in the cranium. Based on our experience, we expect that 3D-CT imaging techniques will become more important in the management of craniosynostosis. (author)

  15. Scanning three-dimensional x-ray diffraction microscopy using a high-energy microbeam

    International Nuclear Information System (INIS)

    Hayashi, Y.; Hirose, Y.; Seno, Y.

    2016-01-01

    A scanning three-dimensional X-ray diffraction (3DXRD) microscope apparatus with a high-energy microbeam was installed at the BL33XU Toyota beamline at SPring-8. The size of the 50 keV beam focused using Kirkpatrick-Baez mirrors was 1.3 μm wide and 1.6 μm high in full width at half maximum. The scanning 3DXRD method was tested for a cold-rolled carbon steel sheet sample. A three-dimensional orientation map with 37 "3 voxels was obtained.

  16. Scanning three-dimensional x-ray diffraction microscopy using a high-energy microbeam

    Energy Technology Data Exchange (ETDEWEB)

    Hayashi, Y., E-mail: y-hayashi@mosk.tytlabs.co.jp; Hirose, Y.; Seno, Y. [Toyota Central R& D Toyota Central R& D Labs., Inc., 41-1 Nagakute Aichi 480-1192 Japan (Japan)

    2016-07-27

    A scanning three-dimensional X-ray diffraction (3DXRD) microscope apparatus with a high-energy microbeam was installed at the BL33XU Toyota beamline at SPring-8. The size of the 50 keV beam focused using Kirkpatrick-Baez mirrors was 1.3 μm wide and 1.6 μm high in full width at half maximum. The scanning 3DXRD method was tested for a cold-rolled carbon steel sheet sample. A three-dimensional orientation map with 37 {sup 3} voxels was obtained.

  17. Sexual difference of human hyoid bones. Quantitative analysis of CT three-dimensional image

    International Nuclear Information System (INIS)

    Terashima, Yoshiharu; Izumi, Masahiro; Hanamura, Hajime; Takada, Yasushi

    2007-01-01

    We investigated sexual differences in hyoid bones of 50 dissected Japanese cadavers: 26 males (aged 52 to 101, averaged 81.9 years) and 24 females (aged 61 to 94, averaged 83.6 years). All extracted hyoid bones were scanned by multi-slice CT. Length of body, distance between bilateral greater horns, length of greater horns, distance between bilateral lesser horns, and length of lesser horns were measured on CT three-dimensional image, and were analyzed by univariate and multivariate statistics. t-tests showed significant sexual differences in all the dimensions; being about 20% longer in males than in females. In principal component analysis using five hyoid dimensions, factor 1, expressing the overall size of the bone, fairly separated each sex, but factors 2 and 3, expressing the shape, did not. Discriminant analysis by a stepwise model, using all the eight dimensions, classified sex rightly (88.6% of the bone) by a function of two dimensions: length of body and distance between bilateral tips of lesser horns. In conclusion, a sexual difference of the hyoid bone was evident in size rather than in shape. (author)

  18. Determination of optimal parameters for three-dimensional reconstruction images of central airways using helical CT

    International Nuclear Information System (INIS)

    Hirose, Takahumi; Akata, Soichi; Matsuno, Naoto; Nagao, Takeshi; Abe, Kimihiko

    2002-01-01

    Three-dimensional (3D) image reconstruction of central airways using helical CT requires several user-defined parameters that exceed the requirements of conventional CT. The purpose of this study was to evaluate the optimal parameters for 3D images of central airways using helical CT. In our experimental study using a piglet immediately after sacrifice, 3D images of the central airway were evaluated with changes of 3D imaging parameters, such as detector collimation (1, 2, 3 and 6 mm), table speed (1, 2, 3 and 5 mm/sec), tube electric current (50, 100, 150, 200 and 250 mA), reconstruction interval (0.3, 0.5, 1, 2 and 3 mm), algorithm (mediastinum and lung) and interpolation method (180 deg and 360 deg). To minimize detector collimation, table speed, and reconstruction interval could provide the best 3D images of the central airway. Stair-step artifacts could also be reduced with a slow table speed. However, decreasing the collimation and table speed decreases not only the effective section thickness but also the scan coverage that can be achieved with a helical CT. For routine diagnosis, we conclude that optimal parameters for 3D images of the central airway are to minimize the table speed necessary to cover the volume of interest and to set detector collimation to 1/2 of the table speed. The reconstruction intervals should also be selected at up to 1/2 of the detector collimation, but with trade-offs of increased image processing time, data storage requirements, and physician time for image review. Regarding to tube electric current, 200 mA or more was necessary. Pixel noise increased with the algorithm for the lung. The 180 deg interpolation is better than 360 deg interpolation due to thin effective section thickness. (author)

  19. Two- and three-dimensional CT evaluation of sacral and pelvic anomalies

    International Nuclear Information System (INIS)

    Kuhlman, J.E.; Fishman, E.K.; Magid, D.

    1988-01-01

    Pelvic anomalies are difficult to evaluate with standard techniques. Detailed knowledge of the existing pelvic structures and musculature is essential for successful repair. The authors evaluated 12 patients with complex malformations of the pelvis using two- and three-dimensional imaging. The anomalies included bladder exstrophy (n = 4), cloacal exstrophy (n = 1), duplicated and absent sacrum (n = 3), myelomeningoceles (n = 2), and diastrophic dwarfism (n = 2). The two-dimensional images consisted of sequential coronal and sagittal reconstructions that could be reviewed dynamically on screen. Three-dimensional images were generated on the Pixar imaging computer with use of volumetric rendering. Two- and three-dimensional CT proved complementary in the evaluation of pelvic anomalies, providing optimal information from transaxial CT data

  20. Three-dimensional CT and MR imaging in congenital dislocation of the hip: Technical considerations

    International Nuclear Information System (INIS)

    Lang, P.; Steiger, P.; Lindquist, T.; Skinner, S.; Moore, S.; Chafetz, N.I.; Genant, H.K.

    1987-01-01

    Two-dimensional (2D) software techniques were developed to generate diagnostic-quality three-dimensional (3D) MR studies in two patients with congenital dislocation of the hip. Comparable 3D CT studies were obtained in two other patients. Unsharp masks were divided into the original MR images to correct for local variations in signal intensity. Combinations of first- and second-echo images improved the object contrast. Pixels with insufficient homogeneity relative to their neighboring data were excluded. CT did not require 2D preprocessing. Three-dimensional CT and MR images demonstrated subluxation and dislocation. 3D MR, in contrast to CT, demonstrated the cartilaginous femoral head. The described 2D MR preprocessing provides diagnostic-quality 3D MR studies. It will be useful for generating 3D MR images of other anatomic structures

  1. High-resolution three-dimensional visualization of the rat spinal cord microvasculature by synchrotron radiation micro-CT

    Energy Technology Data Exchange (ETDEWEB)

    Hu, Jianzhong; Cao, Yong; Wu, Tianding; Li, Dongzhe [Department of Spine Surgery, Xiangya Hospital, Central South University, Changsha 410008 (China); Lu, Hongbin, E-mail: hongbinlu@hotmail.com [Department of Sports Medicine, Research Centre of Sports Medicine, Xiangya Hospital, Central South University, Changsha 410008 (China)

    2014-10-15

    Purpose: Understanding the three-dimensional (3D) morphology of the spinal cord microvasculature has been limited by the lack of an effective high-resolution imaging technique. In this study, synchrotron radiation microcomputed tomography (SRµCT), a novel imaging technique based on absorption imaging, was evaluated with regard to the detection of the 3D morphology of the rat spinal cord microvasculature. Methods: Ten Sprague-Dawley rats were used in this ex vivo study. After contrast agent perfusion, their spinal cords were isolated and scanned using conventional x-rays, conventional micro-CT (CµCT), and SRµCT. Results: Based on contrast agent perfusion, the microvasculature of the rat spinal cord was clearly visualized for the first time ex vivo in 3D by means of SRµCT scanning. Compared to conventional imaging techniques, SRµCT achieved higher resolution 3D vascular imaging, with the smallest vessel that could be distinguished approximately 7.4 μm in diameter. Additionally, a 3D pseudocolored image of the spinal cord microvasculature was generated in a single session of SRµCT imaging, which was conducive to detailed observation of the vessel morphology. Conclusions: The results of this study indicated that SRµCT scanning could provide higher resolution images of the vascular network of the spinal cord. This modality also has the potential to serve as a powerful imaging tool for the investigation of morphology changes in the 3D angioarchitecture of the neurovasculature in preclinical research.

  2. Improvement in printing technique of spiral CT three-dimensional colour image

    International Nuclear Information System (INIS)

    Wang Yicheng; Liu Feng; Zhang Ling

    2005-01-01

    Objective: To investigate the printing technique of spiral CT three-dimensional (3D) colour image. Methods: The 3D colour images of 136 patients were printed, with the equipment of Marconi spiral CT, personnel computer, colour ink printer, and network switchboard. Results: All printed images were satisfied by this method. Conclusion: This technique is economic, simple, and useful, and can meet the need for clinical diagnosis and operation. (authors)

  3. Image-guided stereotactic surgery using ultrasonography and reconstructive three-dimensional CT-imaging system

    International Nuclear Information System (INIS)

    Kawamura, Hirotsune; Iseki, Hiroshi; Umezawa, Yoshihiro

    1991-01-01

    A new simulation and navigation system utilizing three-dimensional CT images has been developed for image-guided stereotactic surgery. Preoperative CT images are not always useful in predicting the intraoperative location of lesions, for cerebral lesions are easily displaced or distorted by gravity, brain retraction, and/or CSF aspiration during operative procedure. This new system, however, has the advantage that the intraoperative locations of intracranial lesions or the anatomical structures of the brain can be precisely confirmed during stereotactic surgery. Serial CT images were obtained from a patient whose head had been fixed to the ISEKI CT-guided stereotactic frame. The data of serial CT images were saved on a floppy disc and then transferred to the work station (IRIS) using the off line. In order to find the best approach angle for ultrasound-guided stereotactic surgery, three-dimenstional CT images were reconstructed using the work station. The site of the craniotomy or the angle of the trajectory of the ultrasound probe was measured preoperatively based on the three-dimensional CT images. Then, in the operating room, the patient's head was fixed to the ISEKI frame with the subframe at the same position as before according to the measurement of the CT images. In a case of cystic glioma, the predicable ultrasonograms from three-dimensional reconstructive CT images were ascertained to correspond well to the actual ultrasound images during ultrasound-guided stereotactic surgery. Therefore, the new simulation and navigation system can be judged to be a powerful operative supporting modality for correcting the locations of cerebral lesions; it allows one to perform stereotactic surgery more accurately and less invasively. (author)

  4. Three-dimensional patient setup errors at different treatment sites measured by the Tomotherapy megavoltage CT

    Energy Technology Data Exchange (ETDEWEB)

    Hui, S.K.; Lusczek, E.; Dusenbery, K. [Univ. of Minnesota Medical School, Minneapolis, MN (United States). Dept. of Therapeutic Radiology - Radiation Oncology; DeFor, T. [Univ. of Minnesota Medical School, Minneapolis, MN (United States). Biostatistics and Informatics Core; Levitt, S. [Univ. of Minnesota Medical School, Minneapolis, MN (United States). Dept. of Therapeutic Radiology - Radiation Oncology; Karolinska Institutet, Stockholm (Sweden). Dept. of Onkol-Patol

    2012-04-15

    Reduction of interfraction setup uncertainty is vital for assuring the accuracy of conformal radiotherapy. We report a systematic study of setup error to assess patients' three-dimensional (3D) localization at various treatment sites. Tomotherapy megavoltage CT (MVCT) images were scanned daily in 259 patients from 2005-2008. We analyzed 6,465 MVCT images to measure setup error for head and neck (H and N), chest/thorax, abdomen, prostate, legs, and total marrow irradiation (TMI). Statistical comparisons of the absolute displacements across sites and time were performed in rotation (R), lateral (x), craniocaudal (y), and vertical (z) directions. The global systematic errors were measured to be less than 3 mm in each direction with increasing order of errors for different sites: H and N, prostate, chest, pelvis, spine, legs, and TMI. The differences in displacements in the x, y, and z directions, and 3D average displacement between treatment sites were significant (p < 0.01). Overall improvement in patient localization with time (after 3-4 treatment fractions) was observed. Large displacement (> 5 mm) was observed in the 75{sup th} percentile of the patient groups for chest, pelvis, legs, and spine in the x and y direction in the second week of the treatment. MVCT imaging is essential for determining 3D setup error and to reduce uncertainty in localization at all anatomical locations. Setup error evaluation should be performed daily for all treatment regions, preferably for all treatment fractions. (orig.)

  5. Endoscopic mode for three-dimensional CT display of normal and pathologic laryngeal structures

    International Nuclear Information System (INIS)

    Sanuki, Tetsuji; Hyodo, Masamitsu; Yumoto, Eiji; Yasuhara, Yoshifumi; Ochi, Takashi

    1997-01-01

    The recent development of helical (spiral) computed tomography allows collection of volumetric data to obtain high quality three-dimensional (3D) reconstructed images. The authors applied the 3D CT endoscopic imaging technique to asses normal and pathologic laryngeal structures. The latter included trauma, vocal fold atrophy, cancer of the larynx and recurrent nerve palsy. This technique was able to show normal laryngeal structures and characteristic findings of each pathology. The 3D CT endoscopic images can be rotated around any axis, allowing optimal depiction of pathologic lesion. The use of 3D CT endoscopic technique provides the display of the location and extent of pathology and affords accurate therapeutic planning. (author)

  6. An improved three-dimensional non-scanning laser imaging system based on digital micromirror device

    Science.gov (United States)

    Xia, Wenze; Han, Shaokun; Lei, Jieyu; Zhai, Yu; Timofeev, Alexander N.

    2018-01-01

    Nowadays, there are two main methods to realize three-dimensional non-scanning laser imaging detection, which are detection method based on APD and detection method based on Streak Tube. However, the detection method based on APD possesses some disadvantages, such as small number of pixels, big pixel interval and complex supporting circuit. The detection method based on Streak Tube possesses some disadvantages, such as big volume, bad reliability and high cost. In order to resolve the above questions, this paper proposes an improved three-dimensional non-scanning laser imaging system based on Digital Micromirror Device. In this imaging system, accurate control of laser beams and compact design of imaging structure are realized by several quarter-wave plates and a polarizing beam splitter. The remapping fiber optics is used to sample the image plane of receiving optical lens, and transform the image into line light resource, which can realize the non-scanning imaging principle. The Digital Micromirror Device is used to convert laser pulses from temporal domain to spatial domain. The CCD with strong sensitivity is used to detect the final reflected laser pulses. In this paper, we also use an algorithm which is used to simulate this improved laser imaging system. In the last, the simulated imaging experiment demonstrates that this improved laser imaging system can realize three-dimensional non-scanning laser imaging detection.

  7. Evaluation of oral scanning in comparison to impression using three-dimensional registration

    Science.gov (United States)

    Brogle-Kim, Yur-Chung; Deyhle, Hans; Müller, Bert; Schulz, Georg; Bormann, Therese; Beckmann, Felix; Jäger, Kurt

    2012-10-01

    Crown and bridge restorations are one of the main treatment methods in fixed prosthodontics. The fabrication requires data on the patient's denture shape. This information is generally obtained as a hard copy from an impression mold. Alternatively, one can acquire the data electronically using oral optical three-dimensional (3D) imaging techniques, which determine the surface of the denture. The aim of the study was to quantitatively compare the accuracy of three dimensional scanning with that of conventional impressions and give a statement how far the scanner provides a clinical alternative with equal or better precision. Data from 10 teeth were acquired in the dental office with a polyether impression material and an oral scanner. Data from the impressions were digitalized by means of micro computed tomography. The data were then 3D registered to identify the potential differences between impression and optical scan. We could demonstrate that the oral scanner's data and the conventional impressions are comparable.

  8. On the use of video projectors for three-dimensional scanning

    Science.gov (United States)

    Juarez-Salazar, Rigoberto; Diaz-Ramirez, Victor H.; Robledo-Sanchez, Carlos; Diaz-Gonzalez, Gerardo

    2017-08-01

    Structured light projection is one of the most useful methods for accurate three-dimensional scanning. Video projectors are typically used as the illumination source. However, because video projectors are not designed for structured light systems, some considerations such as gamma calibration must be taken into account. In this work, we present a simple method for gamma calibration of video projectors. First, the experimental fringe patterns are normalized. Then, the samples of the fringe patterns are sorted in ascending order. The sample sorting leads to a simple three-parameter sine curve that is fitted using the Gauss-Newton algorithm. The novelty of this method is that the sorting process removes the effect of the unknown phase. Thus, the resulting gamma calibration algorithm is significantly simplified. The feasibility of the proposed method is illustrated in a three-dimensional scanning experiment.

  9. Virtual reality publication of spiral ct-derived three-dimensional models: or, creation of spiral, CT-derived, three-dimensional VRML objects.

    Science.gov (United States)

    Tyszka, J M

    1997-01-01

    Three-dimensional models can be generated from slice images, such as those obtained from computed tomography (CT) and magnetic resonance imaging (MRI) using a variety of techniques. A popular method for rendering 3D anatomical models is the creation of polygonal mesh surfaces representing the boundary between tissues. Mesh surfaces can be rendered extremely quickly using conventional personal computers, without recourse to more expensive graphic workstations. The dissemination of three-dimensional (3D) models across the Internet has been made significantly easier by the definition of the Virtual Reality Markup Language (VRML) format. The VRML definition allows the parameters and relationships of 3D objects to be described in a text format. The text file can be transfered from a host computer to a remote client computer through the World Wide Web and viewed using readily available software (See Appendix). VRML is based on the definition of primitive 3D objects such as polygons and spheres. Consequently, the transition from a mesh surface derived from a clinical image data set to a VRML object is relatively simple, allowing for convenient and cost-effective dissemination of 3D clinical models across the internet.

  10. Development of Three-Dimensional Dental Scanning Apparatus Using Structured Illumination

    OpenAIRE

    Ahn, Jae Sung; Park, Anjin; Kim, Ju Wan; Lee, Byeong Ha; Eom, Joo Beom

    2017-01-01

    We demonstrated a three-dimensional (3D) dental scanning apparatus based on structured illumination. A liquid lens was used for tuning focus and a piezomotor stage was used for the shift of structured light. A simple algorithm, which detects intensity modulation, was used to perform optical sectioning with structured illumination. We reconstructed a 3D point cloud, which represents the 3D coordinates of the digitized surface of a dental gypsum cast by piling up sectioned images. We performed ...

  11. Volume scanning three-dimensional display with an inclined two-dimensional display and a mirror scanner

    Science.gov (United States)

    Miyazaki, Daisuke; Kawanishi, Tsuyoshi; Nishimura, Yasuhiro; Matsushita, Kenji

    2001-11-01

    A new three-dimensional display system based on a volume-scanning method is demonstrated. To form a three-dimensional real image, an inclined two-dimensional image is rapidly moved with a mirror scanner while the cross-section patterns of a three-dimensional object are displayed sequentially. A vector-scan CRT display unit is used to obtain a high-resolution image. An optical scanning system is constructed with concave mirrors and a galvanometer mirror. It is confirmed that three-dimensional images, formed by the experimental system, satisfy all the criteria for human stereoscopic vision.

  12. Three-dimensional CT diagnosis of myositis ossificans of the sacrospinous ligament

    International Nuclear Information System (INIS)

    Agrons, G.A.; Markowitz, R.I.; Bronson, W.E.

    1993-01-01

    We present the case of a 4-year-old female with a complex fracture of the left hemipelvis who, on follow-up CT imaging, developed new ossific densities within the peripelvic soft tissues of the contralateral side. Three-dimensional surface reformations of the pelvis demonstrated myositis ossificans along the course of the right sacrospinous ligament, thus elucidating unsuspected ligamentous injury and implying prior instability. (orig.)

  13. Three-dimensional CT diagnosis of myositis ossificans of the sacrospinous ligament

    Energy Technology Data Exchange (ETDEWEB)

    Agrons, G.A. (Children' s Hospital of Philadelphia, PA (United States)); Markowitz, R.I. (Children' s Hospital of Philadelphia, PA (United States)); Bronson, W.E. (Children' s Hospital of Philadelphia, PA (United States))

    1993-04-01

    We present the case of a 4-year-old female with a complex fracture of the left hemipelvis who, on follow-up CT imaging, developed new ossific densities within the peripelvic soft tissues of the contralateral side. Three-dimensional surface reformations of the pelvis demonstrated myositis ossificans along the course of the right sacrospinous ligament, thus elucidating unsuspected ligamentous injury and implying prior instability. (orig.)

  14. Diagnosis of temporal bone diseases using three-dimensional images with multislice CT

    Energy Technology Data Exchange (ETDEWEB)

    Toyama, Yoshihiro; Togami, Taro; Murota, Makiko; Fukunaga, Kotaro; Hino, Ichiro; Sato, Katashi; Ohkawa, Motoomi [Kagawa Medical Univ., Miki (Japan)

    2001-08-01

    We evaluated the usefulness of three-dimensional images with multislice CT in the temporal bone diseases. Fifty-nine cases (26 with medial otitis, 8 choresteatoma, 10 congenital malformation, 3 high jugular bulb, 2 otosclerosis, and 10 others) were included in this study. In the ossicular and inner ear lesions, oblique multiplanar images of the long axis of each ossicle was useful the detection of abnormality. Structural deformity of ossicles and bony labyrinth were clearly delineated by surface rendering images. (author)

  15. Three-dimensional display of the heart, aorta, lungs, and airway using CT

    International Nuclear Information System (INIS)

    Fram, E.K.; Godwin, J.D.; Putman, C.E.

    1982-01-01

    In previous studies of human anatomy, three-dimensional display of CT data has required laborious manual boundary tracking, except for high-contrast structures such as the spine. Automated boundary tracking techniques have been extended so that they can function well for both high-contrast and soft-tissue interfaces. These methods have been applied to the in vivo study of human lungs, heart, aorta, and larynx in this paper

  16. Usefulness of preoperative three dimensional CT in laparoscopic cholecystectomy. Especially, its comparison to ERC

    International Nuclear Information System (INIS)

    Machida, Hiromichi; Nakaya, Yuzou; Kojima, Kojirou

    1996-01-01

    We studied the usefulness of three dimensional helical CT (3D-CT) combined with drip infusion cholangiography for determining the application of laparoscopic cholecystectomy (LC) and evaluating the cholecyst severity. The subjects were 56 patients who underwent LC with preoperative 3D-CT. Particularly, in 42 patients undergoing endoscopic retrograde cholangiography (ERC) and 3D-CT simultaneously, the results with both methods were compared. The detection rates of the original site, forward and backward direction, and left and right direction in the confluence form of the cystic duct by means of 3D-CT versus ERC were 100% vs. 92.9% 92.9% vs. 71.4%, and 92.9% vs. 88.1%, respectively. Abnormal biliary distribution was visualized in 5 cases and all of them were depicted by 3D-CT. The 3D-CT was superior to ERC in terms of X-ray dose and cost. These results indicate the usefulness of 3D-CT as a LC preoperative examination. (author)

  17. Utility of three-dimensional helical CT in the diagnosis of breast cancer

    International Nuclear Information System (INIS)

    Maeda, Yoshiaki; Hata, Yoshinobu; Matsuoka, Shinnichi; Nakajima, Nobuhisa; Ito, Toichi; Osada, Tadahiro; Sano, Fumio

    2004-01-01

    Although utility of three-dimensional (3D) helical CT for preoperative examination of breast cancer has been discussed, the accuracy of the helical CT in diagnosing breast cancer has not been fully evaluated. In this study 56 malignant and 28 benign breast tumors were evaluated preoperatively with 3D-helical CT, and their imaging results were compared with pathological findings of surgical specimens. Helical CT identified the presence of malignancy in 54 out of the 56 cancer cases tested and the sensitivity and specificity in distinguishing between malignant and benign tumors were 82% and 57%, respectively. The sensitivity and specificity in diagnosing the presence of metastatic axillary lymph nodes using helical CT were 70% and 80%, respectively. The sensitivity and specificity in diagnosing the presence of extensive intraductal component (EIC) using helical CT were 71% and 86%, respectively. Helical CT visualized all of the tumors in multifocal breast cancer cases. In conclusion, 3D-helical CT is a useful modality for preoperative examination of breast cancer, especially for assessing axillary lymph node status, and EIC, and will be helpful for conducting sentinel lymph node biopsy (SNLB) and breast-conserving surgery. (author)

  18. Application of three-dimensional CT reconstruction technology on inferior oblique muscle in congenital superior oblique palsy

    Directory of Open Access Journals (Sweden)

    Yang Zhang

    2014-05-01

    Full Text Available AIM: To investigate the viability of the morphology of inferior oblique muscle observed stereoscopically using 3-dimensional CT reconstruction technique. METHODS: This control study included of 29 cases which were clinically diagnosed with monocular congenital superior oblique palsy, examined by dimensional CT. The images of the inferior oblique muscle were reconstructed by Mimics software. 3D digital images on the basis of CT scanning data of the individuals were established. Observing the morphology of binocular inferior oblique muscle by self-controlled design, we compared the maximum transverse diameter of inferior oblique muscle of paralyzed eye with non-paralyzed one. We chose 5% as the significant level.RESULTS: The reconstructed results of 3-dimensional CT scan showed that not all of the inferior oblique abdominal muscle of paralyzed eyes were thinner than that of the non-paralyzed eye in maximum transverse diameter of cross-sectional area. The maximum transverse diameter of inferior oblique muscle was measured. The average maximum transverse diameter of the paralyzed eye was 6.797±1.083mm and the non-paralyzed eye was 6.507±0.848mm. The maximum transverse diameter of inferior oblique muscle of paralyzed eye did not, however, differ significantly from the normal(P>0.05. CONCLUSION: The three-dimensional CT reconstruction technology can be used for preoperative evaluation of the morphology of inferior oblique muscle.

  19. Measurement of acetabular morphology under three-dimensional reconstruction of CT and significance

    International Nuclear Information System (INIS)

    Han Yingying; Yang Qiwei; Lai Ying; Hao Shuang; Ma Hecheng; Xiao Chengshuang; Li Youqiong

    2011-01-01

    Objective: To measure the acetabular morphology of Chinese on CT three-dimensional (3D) reconstruction image, and provide the evidence on the prevention and treatment of hip disease. Methods: 96 cases (192 sides) of adult hip CT scans were reconstructed, the acetabular index (AA), center-edge (CE), ACE angle, anteversion angle (AVA), abduction angle (ABA), and vertical diameter (SID) were measured. Results: The total acetabular index was (8.78±5.34)°, of which male was (7.84±5.55)° and female was (9.60±5.06)°. The total CE was (33.59±5.91)°, of which male was (34.55±6.03)° and female was (32.78±5.70)°. The total ACE angle was (29.01±5.65)°, of which male was (28.02±5.94)° and female was (29.80±5.30)°. The total AVA was (20.92±5.55)°, of which male was (20.48±5.08)° and female was (21.25±5.89)°. The total ABA was (51.27±4.16)°, of which male was (51.71±4.37)° and female was (50.89±3.96)°. The total SID was (53.79±3.92) mm, of which male was (56.55±2.64) mm and female was (51.46±3.25) mm. Of the above data, there were statistical differences in the acetabular index, CE angle, ACE angle and acetabular diameter between men and women (P<0.05), Chinese and foreigners (P<0.05). While there was no statistical difference between the left and right sides (P>0.05). Conclusion: There are differences in acetabular morphology between men and women, Chinese and foreigners. Compared with simply using overseas data, it is better to study morphological parameters of native acetabula to instruct the preoperative preparation and operation of national total hip arthroplasty surgery. And it is meaningful to design national parameters. (authors)

  20. Multi-slice CT three dimensional volume measurement of tumors and livers in hepatocellular carcinoma

    International Nuclear Information System (INIS)

    Yu Yuanlong; Li Liangcai; Tang Binghang; Hu Zemin

    2004-01-01

    Objective: To examine the accuracy of multi-slice CT (MSCT) three dimensional (3D) volume measurement of tumors and livers in hepatocellular carcinoma cases by using immersion method as the standard. Methods: (1) The volume of 25 porkling livers was measured using immersion method in experiment group in vitro. Then the models were built according to Matsumoto's method and CT scanning and special software were used to measure the volume of the livers. (2) The volume of the tumors in 25 cases of hepatocellular carcinoma was measured using diameter measurement method and special volume measurement software (tissue measurements). Two tumors of them were measured respectively using MSCT 3D measurement, diameter measurement before the operation and immersion method after the operation. The data of the two groups were examined using pairing t test. Results: (1) The volume range of 25 porkling livers was 68.50-1150.10 ml using immersion method and 69.78-1069.97 ml using MSCT 3D measurement. There was no significant difference of the data in these two groups using t-test (t=1.427, P>0.05). (2) The volume range of 25 hepatocellular tumors was 395.16-2747.7 ml using diameter measurement and 203.10-1463.19 ml using MSCT 3D measurement before the operation. There was significant difference of the data in these two groups using t-test (t=7.689, P<0.001). In 2 ablated tumors, 1 case's volume was (21.75±0.60) ml using MSCT 3D measurement and 33.73 ml using diameter measurement before the operation and 21.50 ml using immersion measurement after the operation. The other case's volume was (696.13±5.30) ml using MSCT 3D measurement and 1323.51 ml using diameter measurement before the operation and 685.50 ml using immersion measurement after the operation. Conclusion: MSCT 3D volume measurement can accurately measure the volume of tumor and liver and has important clinical application value. There is no significant difference between MSCT 3D volume measurement and immersion method

  1. Development of an automated extraction method for liver tumors in three dimensional multiphase multislice CT images

    International Nuclear Information System (INIS)

    Nakagawa, Junya; Shimizu, Akinobu; Kobatake, Hidefumi

    2004-01-01

    This paper proposes a tumor detection method using four phase three dimensional (3D) CT images of livers, i.e. non-contrast, early, portal, and late phase images. The method extracts liver regions from the four phase images and enhances tumors in the livers using a 3D adaptive convergence index filter. Then it detects local maximum points and extracts tumor candidates by a region growing method. Subsequently several features of the candidates are measured and each candidate is classified into true tumor or normal tissue based on Mahalanobis distances. Above processes except liver region extraction are applied to four phase images, independently and four resultant images are integrated into one. We applied the proposed method to 3D abdominal CT images of ten patients obtained with multi-detector row CT scanner and confirmed that tumor detection rate was 100% without false positives, which was quite promising results. (author)

  2. Assessment of the usefulness of three-dimensional CT angiography after peripheral arterial bypass surgery

    International Nuclear Information System (INIS)

    Hayashi, Saihou; Sasaki, Masaru; Kawamoto, Jun

    1997-01-01

    Conventional CT and three-dimensional CT angiography (3D-CTA) were conducted after peripheral arterial bypass surgery on 17 patients (26 grafts) from October, 1994 to April, 1996. Seventeen grafts were patent. The following objectives were satisfied in these cases: 1. Prosthetic graft or saphenous vein was depicted by 3D-CTA, 2. The distal portion of the native artery was depicted by 3D-CTA, and 3. Opacification of the graft interior was recognized by transverse section of CT. Nine grafts were occluded but prosthetic grafts were depicted in 5 cases, and prosthetic grafts and the distal portions of native arteries in 3 cases. Opacification of the graft interior was not seen in any case. Achievement of the above three objectives was considered necessary to determine graft patency. (author)

  3. Scanning ion conductance microscopy for visualizing the three-dimensional surface topography of cells and tissues.

    Science.gov (United States)

    Nakajima, Masato; Mizutani, Yusuke; Iwata, Futoshi; Ushiki, Tatsuo

    2018-01-01

    Scanning ion conductance microscopy (SICM), which belongs to the family of scanning probe microscopy, regulates the tip-sample distance by monitoring the ion current through the use of an electrolyte-filled nanopipette as the probing tip. Thus, SICM enables "contact-free" imaging of cell surface topography in liquid conditions. In this paper, we applied hopping mode SICM for obtaining topographical images of convoluted tissue samples such as trachea and kidney in phosphate buffered saline. Some of the SICM images were compared with the images obtained by scanning electron microscopy (SEM) after drying the same samples. We showed that the imaging quality of hopping mode SICM was excellent enough for investigating the three-dimensional surface structure of the soft tissue samples. Thus, SICM is expected to be used for imaging a wide variety of cells and tissues - either fixed or alive- at high resolution under physiologically relevant liquid conditions. Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. Three-dimensional motion analysis of an improved head immobilization system for simulation, CT, MRI, and PET imaging

    International Nuclear Information System (INIS)

    Thornton, A.F. Jr.; Ten Haken, R.K.; Gerhardsson, A.; Correll, M.

    1991-01-01

    A mask/marker immobilization system for the routine radiation therapy treatment of head and neck disease is described, utilizing a commercially available thermoplastic mesh, indexed and mounted for a rigid frame attached to the therapy couch. Designed to permit CT, MRI, and PET diagnostics scans of the patient to be performed in the simulation and treatment position employing the same mask, the system has been tested in order to demonstrate the reproducibility of immobilization throughout a radical course of irradiation. Three-dimensional analysis of patient position over an 8-week course of daily radiation treatment has been performed for 9 patients from digitization of anatomic points identified on orthogonal radiographs. Studies employing weekly constructed system permits rapid mask formation to be performed on the treatment simulator, resulting in an immobilization device comparable to masks produced with vacuum-forming techniques. Details of motion analysis and central axis CT, MRI, and PET markers are offered. (author). 16 refs.; 3 figs

  5. The interpolation method based on endpoint coordinate for CT three-dimensional image

    International Nuclear Information System (INIS)

    Suto, Yasuzo; Ueno, Shigeru.

    1997-01-01

    Image interpolation is frequently used to improve slice resolution to reach spatial resolution. Improved quality of reconstructed three-dimensional images can be attained with this technique as a result. Linear interpolation is a well-known and widely used method. The distance-image method, which is a non-linear interpolation technique, is also used to convert CT value images to distance images. This paper describes a newly developed method that makes use of end-point coordinates: CT-value images are initially converted to binary images by thresholding them and then sequences of pixels with 1-value are arranged in vertical or horizontal directions. A sequence of pixels with 1-value is defined as a line segment which has starting and end points. For each pair of adjacent line segments, another line segment was composed by spatial interpolation of the start and end points. Binary slice images are constructed from the composed line segments. Three-dimensional images were reconstructed from clinical X-ray CT images, using three different interpolation methods and their quality and processing speed were evaluated and compared. (author)

  6. Three-dimensional CT angiography in the diagnosis of cerebrovascular disease

    International Nuclear Information System (INIS)

    Eguchi, Takahiko; Nikaido, Yuji; Nakamura, Takeshi; Yoneda, Shigeru

    1995-01-01

    We reported the usefulness of three dimensional CT angiography (3 DCTA) in cerebrovascular disease. Twenty two of twenty three intracerebral aneurysms were visualized in 3 DCTA. 3 DTPA was especially useful for the evaluation of posterior-projection anterior communicating arteries and the distinction between a carotid-posterior communicating aneurysm and an infundibular dilatation. An anterior-projection carotid bifurcation aneurysm, which we missed in DSA, was visualized clearly in 3 DCTA. Stenotic cervical carotid artery lesions were well evaluated in 3 DCTA, including ulceration. 3 DCTA was not so useful for evaluation of intracranial artery stenosis. 3 DCTA was useful as a non-invasive method to evaluate cerebrovascular diseases. (author)

  7. Endoscopic visualization of luminal organ and great vessels with three dimensional CT scanner

    International Nuclear Information System (INIS)

    Kobayashi, Hisashi; Okumura, Toshiyuki; Amemiya, Ryuta; Hasegawa, Hiroshi

    1992-01-01

    Thirty cases examined by three dimensional CT scanner (3DCT) are reported. The observation of inner view using 3DCT were performed in 12 large vessels with vascular disorder, 10 pulmonary bronchi with lung cancer and 8 common bile ducts involved obstructive disease. In order to visualize interface of the lumen, a new software, which was developed by HITACHI MEDICO Inc., was used. In all cases but one the inner view of the luminal organ was clearly demonstrated as 3D images and it was possible to judge some changes of luminal interface involved by the diseases. The 3DCT endoscopic image might be useful as a new endoscopic technique without fiberscopy. (author)

  8. Three dimensional volume rendering virtual endoscopy of the ossicles using a multi-row detector CT: applications and limitations

    International Nuclear Information System (INIS)

    Kim, Su Yeon; Choi, Sun Seob; Kang, Myung Jin; Shin, Tae Beom; Lee, Ki Nam; Kang, Myung Koo

    2005-01-01

    This study was conducted to know the applications and limitations of three dimensional volume rendering virtual endoscopy of the ossicles using a multi-row detector CT. This study examined 25 patients who underwent temporal bone CT using a 16-row detector CT as a result of hearing problems or trauma. The axial CT scan of the temporal bone was performed with a 0.6 mm collimation, and a reconstruction was carried out with a U70u sharp of kernel value, a 1 mm thickness and 0.5-1.0 mm increments. After observing the ossicles in the axial and coronal images, virtual endoscopy was performed using a three dimensional volume rendering technique with a threshold value of-500 HU. The intra-operative otoendoscopy was performed in 12 ears, and was compared with the virtual endoscopy findings. Virtual endoscopy of the 29 ears without hearing problems demonstrated hypoplastic or an incomplete depiction of the stapes superstructures in 25 ears and a normal depiction in 4 ears. Virtual endoscopy of 21 ears with hearing problems demonstrated no ossicles in 1 ears, no malleus in 3 ears, a malleoincudal subluxation in 6 ears, a dysplastic incus in 5 ears, an incudostapedial subluxation in 9 ears, dysplastic stapes in 2 ears, a hypoplastic or incomplete depiction of the stapes in 16 ears and no stapes in 1 ears. In contrast to the intra-operative otoendoscopy, 8 out of 12 ears showed a hypoplastic or deformed stapes in the virtual endoscopy. Volume rendering virtual endoscopy using a multi-row detector CT is an excellent method for evaluation the ossicles in three dimension, even thought the partial volume effect for the stapes superstructures needs to be considered

  9. The use of a neuronavigator in combination with three-dimensional CT reconstruction and angiography

    Energy Technology Data Exchange (ETDEWEB)

    Watanabe, Eiju; Mayanagi, Yoshiaki (Tokyo Metropolitan Police Hospital (Japan)); Ishii, Shigeo; Yoshimoto, Satonobu; Takakura, Kintomo

    1989-08-01

    A new CT-stereotactic device (navigator) has been developed which translates the operating site into preoperative CT coordination. We applied this system in combination with three-dimensional CT reconstruction and with angiogram. Method: The system consists of a 6-joint robotic arm and a personal computer. It projects the location of the arm tip onto a correlating CT slice with a cursor, which guides a surgeon toward his intracranial target during open surgery. The system translates the tip location into a 3D-CT reconstructed image and an angiogram. The system worked as the core of a multimodality navigation system during surgery. The detection error was less than 5 mm, which proved sufficient for open microsurgery. The system was combined with a 3D-CT reconstruction system. It produces 3D images and cuts off the surface image at the point of the cursor, simulating surgical excision. The navigator controlled the location of the cutting cursor, thus establishing a real-time surgical simulation. When the angiogram was referred to, it became easy to identify bridging veins within a small operating field. Conclusion: The neuronavigator combines various diagnostic images into one data base and effectively guides the surgeon during surgery. (author).

  10. The use of a neuronavigator in combination with three-dimensional CT reconstruction and angiography

    International Nuclear Information System (INIS)

    Watanabe, Eiju; Mayanagi, Yoshiaki; Ishii, Shigeo; Yoshimoto, Satonobu; Takakura, Kintomo.

    1989-01-01

    A new CT-stereotactic device (navigator) has been developed which translates the operating site into preoperative CT coordination. We applied this system in combination with three-dimensional CT reconstruction and with angiogram. Method: The system consists of a 6-joint robotic arm and a personal computer. It projects the location of the arm tip onto a correlating CT slice with a cursor, which guides a surgeon toward his intracranial target during open surgery. The system translates the tip location into a 3D-CT reconstructed image and an angiogram. The system worked as the core of a multimodality navigation system during surgery. The detection error was less than 5 mm, which proved sufficient for open microsurgery. The system was combined with a 3D-CT reconstruction system. It produces 3D images and cuts off the surface image at the point of the cursor, simulating surgical excision. The navigator controlled the location of the cutting cursor, thus establishing a real-time surgical simulation. When the angiogram was referred to, it became easy to identify bridging veins within a small operating field. Conclusion: The neuronavigator combines various diagnostic images into one data base and effectively guides the surgeon during surgery. (author)

  11. Spinal CT scan, 1

    International Nuclear Information System (INIS)

    Nakagawa, Hiroshi

    1982-01-01

    Methods of CT of the cervical and thoracic spines were explained, and normal CT pictures of them were described. Spinal CT was evaluated in comparison with other methods in various spinal diseases. Plain CT revealed stenosis due to spondylosis or ossification of posterior longitudinal ligament and hernia of intervertebral disc. CT took an important role in the diagnosis of spinal cord tumors with calcification and destruction of the bone. CT scan in combination with other methods was also useful for the diagnosis of spinal injuries, congenital anomalies and infections. (Ueda, J.)

  12. Three-Dimensional Digital Documentation of Heritage Sites Using Terrestrial Laser Scanning and Unmanned Aerial Vehicle Photogrammetry

    Science.gov (United States)

    Jo, Y. H.; Kim, J. Y.

    2017-08-01

    Three-dimensional digital documentation is an important technique for the maintenance and monitoring of cultural heritage sites. This study focuses on the three-dimensional digital documentation of the Magoksa Temple, Republic of Korea, using a combination of terrestrial laser scanning and unmanned aerial vehicle (UAV) photogrammetry. Terrestrial laser scanning mostly acquired the vertical geometry of the buildings. In addition, the digital orthoimage produced by UAV photogrammetry had higher horizontal data acquisition rate than that produced by terrestrial laser scanning. Thus, the scanning and UAV photogrammetry were merged by matching 20 corresponding points and an absolute coordinate system was established using seven ground control points. The final, complete threedimensional shape had perfect horizontal and vertical geometries. This study demonstrates the potential of integrating terrestrial laser scanning and UAV photogrammetry for three-dimensional digital documentation. This new technique is expected to contribute to the three-dimensional digital documentation and spatial analysis of cultural heritage sites.

  13. Three-dimensional image display by CT data processing and clinical applications in orthopaedics and craniofacial surgery

    International Nuclear Information System (INIS)

    Zonneveld, F.W.; Akkerveeken, P.F. van; Koornneef, L.

    1988-01-01

    The methods of generating three-dimensional images from two-dimensional CT data are described. Four cases are reported explaining its use in the planning of orthopaedic and craniofacial surgery. (orig.) [de

  14. Deviation of landmarks in accordance with methods of establishing reference planes in three-dimensional facial CT evaluation.

    Science.gov (United States)

    Yoon, Kaeng Won; Yoon, Suk-Ja; Kang, Byung-Cheol; Kim, Young-Hee; Kook, Min Suk; Lee, Jae-Seo; Palomo, Juan Martin

    2014-09-01

    This study aimed to investigate the deviation of landmarks from horizontal or midsagittal reference planes according to the methods of establishing reference planes. Computed tomography (CT) scans of 18 patients who received orthodontic and orthognathic surgical treatment were reviewed. Each CT scan was reconstructed by three methods for establishing three orthogonal reference planes (namely, the horizontal, midsagittal, and coronal reference planes). The horizontal (bilateral porions and bilateral orbitales) and midsagittal (crista galli, nasion, prechiasmatic point, opisthion, and anterior nasal spine) landmarks were identified on each CT scan. Vertical deviation of the horizontal landmarks and horizontal deviation of the midsagittal landmarks were measured. The porion and orbitale, which were not involved in establishing the horizontal reference plane, were found to deviate vertically from the horizontal reference plane in the three methods. The midsagittal landmarks, which were not used for the midsagittal reference plane, deviated horizontally from the midsagittal reference plane in the three methods. In a three-dimensional facial analysis, the vertical and horizontal deviations of the landmarks from the horizontal and midsagittal reference planes could vary depending on the methods of establishing reference planes.

  15. Deviation of landmarks in accordance with methods of establishing reference planes in three-dimensional facial CT evaluation

    International Nuclear Information System (INIS)

    Yoon, Kaeng Won; Yoon, Suk Ja; Kang, Byung Cheol; Kook, Min Suk; Lee, Jae Seo; Kim, Young Hee; Palomo, Juan Martin

    2014-01-01

    This study aimed to investigate the deviation of landmarks from horizontal or midsagittal reference planes according to the methods of establishing reference planes. Computed tomography (CT) scans of 18 patients who received orthodontic and orthognathic surgical treatment were reviewed. Each CT scan was reconstructed by three methods for establishing three orthogonal reference planes (namely, the horizontal, midsagittal, and coronal reference planes). The horizontal (bilateral porions and bilateral orbitales) and midsagittal (crista galli, nasion, prechiasmatic point, opisthion, and anterior nasal spine) landmarks were identified on each CT scan. Vertical deviation of the horizontal landmarks and horizontal deviation of the midsagittal landmarks were measured. The porion and orbitale, which were not involved in establishing the horizontal reference plane, were found to deviate vertically from the horizontal reference plane in the three methods. The midsagittal landmarks, which were not used for the midsagittal reference plane, deviated horizontally from the midsagittal reference plane in the three methods. In a three-dimensional facial analysis, the vertical and horizontal deviations of the landmarks from the horizontal and midsagittal reference planes could vary depending on the methods of establishing reference planes.

  16. Deviation of landmarks in accordance with methods of establishing reference planes in three-dimensional facial CT evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, Kaeng Won; Yoon, Suk Ja; Kang, Byung Cheol; Kook, Min Suk; Lee, Jae Seo [School of Dentistry, Dental Science Research Institute, Chonnam National University, Gwangju (Korea, Republic of); Kim, Young Hee [Dept. of Oral and Maxillofacial Radiology, Hallym University Sacred Heart Hospital, Anyang (Korea, Republic of); Palomo, Juan Martin [Dept. of Orthodontics, School of Dental Medicine, Case Western Reserve University, Cleveland (Korea, Republic of)

    2014-09-15

    This study aimed to investigate the deviation of landmarks from horizontal or midsagittal reference planes according to the methods of establishing reference planes. Computed tomography (CT) scans of 18 patients who received orthodontic and orthognathic surgical treatment were reviewed. Each CT scan was reconstructed by three methods for establishing three orthogonal reference planes (namely, the horizontal, midsagittal, and coronal reference planes). The horizontal (bilateral porions and bilateral orbitales) and midsagittal (crista galli, nasion, prechiasmatic point, opisthion, and anterior nasal spine) landmarks were identified on each CT scan. Vertical deviation of the horizontal landmarks and horizontal deviation of the midsagittal landmarks were measured. The porion and orbitale, which were not involved in establishing the horizontal reference plane, were found to deviate vertically from the horizontal reference plane in the three methods. The midsagittal landmarks, which were not used for the midsagittal reference plane, deviated horizontally from the midsagittal reference plane in the three methods. In a three-dimensional facial analysis, the vertical and horizontal deviations of the landmarks from the horizontal and midsagittal reference planes could vary depending on the methods of establishing reference planes.

  17. Three-dimensional optical transfer functions in the aberration-corrected scanning transmission electron microscope.

    Science.gov (United States)

    Jones, L; Nellist, P D

    2014-05-01

    In the scanning transmission electron microscope, hardware aberration correctors can now correct for the positive spherical aberration of round electron lenses. These correctors make use of nonround optics such as hexapoles or octupoles, leading to the limiting aberrations often being of a nonround type. Here we explore the effect of a number of potential limiting aberrations on the imaging performance of the scanning transmission electron microscope through their resulting optical transfer functions. In particular, the response of the optical transfer function to changes in defocus are examined, given that this is the final aberration to be tuned just before image acquisition. The resulting three-dimensional optical transfer functions also allow an assessment of the performance of a system for focal-series experiments or optical sectioning applications. © 2014 The Authors Journal of Microscopy © 2014 Royal Microscopical Society.

  18. Three-dimensional imaging and scanning: Current and future applications for pathology

    Directory of Open Access Journals (Sweden)

    Navid Farahani

    2017-01-01

    Full Text Available Imaging is vital for the assessment of physiologic and phenotypic details. In the past, biomedical imaging was heavily reliant on analog, low-throughput methods, which would produce two-dimensional images. However, newer, digital, and high-throughput three-dimensional (3D imaging methods, which rely on computer vision and computer graphics, are transforming the way biomedical professionals practice. 3D imaging has been useful in diagnostic, prognostic, and therapeutic decision-making for the medical and biomedical professions. Herein, we summarize current imaging methods that enable optimal 3D histopathologic reconstruction: Scanning, 3D scanning, and whole slide imaging. Briefly mentioned are emerging platforms, which combine robotics, sectioning, and imaging in their pursuit to digitize and automate the entire microscopy workflow. Finally, both current and emerging 3D imaging methods are discussed in relation to current and future applications within the context of pathology.

  19. Clinical application of three-dimensional spiral CT cerebral angiography with volume rendering

    International Nuclear Information System (INIS)

    Duan Shaoyin; Huang Xi'en; Kang Jianghe; Zhang Dantong; Lin Qingchi; Cai Guoxiang; Xu Meixin; Pang Ruilin

    2002-01-01

    Objective: To study the methodology and assess the clinical value of three-dimensional CT angiography (3D-CTA) with volume rendering (VR) in cerebral vessels. Methods: Sixty-two patients were examined by means of 3D-CTA with volume rendering. VR was used in the reconstruction of 3D images, and the demonstration of normal vessels and vascular lesions were particularly analyzed. At the same time, comparisons were made between the images of VR and SSD, MIP, and also between the diagnosis of VR-CTA and DSA or postoperative results. Results: In VR images, cerebral vessel routes and vessel cavities were showed clearly, while the relationship among vascular lesions, surrounding vessels, and neighboring structure was distinguished. 50 cases (80.6%) were found positive, 48 of which were correct and 2 were false-positive compared with DSA or postoperative results. The accurate rate of diagnosis was 96.0%. There was no obvious difference in showing the cerebral vessel among the images of VR, SSD and MIP (P > 0.25). Conclusion: Three-dimensional CT cerebral angiography with VR is a new noninvasive effective method. It can even partly replace the DSA. The 3D-images have the characteristics of showing the cerebral vascular cavity and overlapped vessels without cutting the skull

  20. Morphometric analysis of acetabular dysplasia in cerebral palsy: three-dimensional CT study.

    Science.gov (United States)

    Gose, Shinichi; Sakai, Takashi; Shibata, Toru; Murase, Tsuyoshi; Yoshikawa, Hideki; Sugamoto, Kazuomi

    2009-12-01

    Three-dimensional computed tomography (3D-CT) eliminates the positioning errors and allows the clinician to more accurately assess the radiographic parameters present. To elucidate the 3D geometry of the acetabulum and the extent of hip subluxation/dislocation in patients with cerebral palsy (CP), quantitative morphometric analysis was performed using 3D-CT data. We evaluated 150 hips in 75 patients with bilateral spastic CP. The mean age of the patients was 5.4 years (range: 2.7 to 6.9 y). The fitting plane of the ilium was projected onto the coronal plane and then onto the sagittal plane, and then the angle formed with a horizontal line was defined as CTalpha (the lateral opening angle) and CTbeta (the sagittal inclination angle), respectively. The center of the acetabulum and the femoral head were defined, and the distance between these centers was divided by the femoral head diameter, defined as CT migration percentage (CTMP, %). In 123 (82%) of the 150 hips, the femoral head center was located posteriorly, superiorly, and laterally relative to the acetabular center. Large CTalpha cases tended to show large CTMP. CTalpha and CTMP were significantly larger in the cases with Gross Motor Functional Classification System (GMFCS) level IV/V and spastic quadriplegia, than in the cases with GMFCS level II/III and spastic diplegia. CTbeta showed significant correlation with the acetabular defect on the lateral 3D reconstructed images. Three-dimensional acetabular geometry and migration percentage in CP patients can be analyzed quantitatively using 3D-CT regardless of the abnormal spastic posture. The extent of acetabular dysplasia and subluxation is more severe in patients with GMFCS level IV/V and spastic quadriplesia. Level 4.

  1. Clinical application of three-dimensional imaging with multislice CT for laparoscopic colorectal surgery

    International Nuclear Information System (INIS)

    Matsuki, Mitsuru; Okuda, Jyunji; Yoshikawa, Syushi

    2003-01-01

    Laparoscopic colorectal surgery, while minimally invasive, is a complicated technique. Therefore, prior to this surgery, it is important to determine the anatomical information of colorectal cancer. Fifty-eight cases of patients with a confirmed diagnosis of colon cancer [caecal (n=4), ascending colon (n=6), transverse colon (n=7), descending colon (n=2), sigmoid colon (n=22), and rectal (n=17) cancer] were evaluated using multislice CT before laparoscopic surgery. CT examination was performed in an air-filled colorectum by colon fiberscopy. Contrast-enhanced images on multislice CT were obtained at arterial and venous phases. All images were reviewed on a workstation, and three-dimensional (3D) images of vessels, colorectum, cancer, and swollen lymph nodes were reconstructed by volume rendering and fused (integrated 3D imaging). We evaluated the usefulness of integrated 3D imaging with multislice CT for laparoscopic colorectal surgery. Integrated 3D imaging demonstrated clearly the distribution of arteries feeding the colorectal cancer and the anatomical location of colorectal cancer and arterial and venous systems. Moreover, measurement of the distance between the aortic bifurcation and the origin of the inferior mesenteric artery and that between the base of the inferior mesenteric artery and the origin of the left colic artery on integrated 3D imaging contributed to safe, prompt ligation of the vessels and excision of lymph nodes. Integrated 3D imaging with multislice CT was useful for simulation of laparoscopic colorectal surgery. (author)

  2. Clinical application of three-dimensional imaging with multislice CT for laparoscopic colorectal surgery

    Energy Technology Data Exchange (ETDEWEB)

    Matsuki, Mitsuru; Okuda, Jyunji; Yoshikawa, Syushi [Osaka Medical Coll., Takatsuki (Japan)] (and others)

    2003-03-01

    Laparoscopic colorectal surgery, while minimally invasive, is a complicated technique. Therefore, prior to this surgery, it is important to determine the anatomical information of colorectal cancer. Fifty-eight cases of patients with a confirmed diagnosis of colon cancer [caecal (n=4), ascending colon (n=6), transverse colon (n=7), descending colon (n=2), sigmoid colon (n=22), and rectal (n=17) cancer] were evaluated using multislice CT before laparoscopic surgery. CT examination was performed in an air-filled colorectum by colon fiberscopy. Contrast-enhanced images on multislice CT were obtained at arterial and venous phases. All images were reviewed on a workstation, and three-dimensional (3D) images of vessels, colorectum, cancer, and swollen lymph nodes were reconstructed by volume rendering and fused (integrated 3D imaging). We evaluated the usefulness of integrated 3D imaging with multislice CT for laparoscopic colorectal surgery. Integrated 3D imaging demonstrated clearly the distribution of arteries feeding the colorectal cancer and the anatomical location of colorectal cancer and arterial and venous systems. Moreover, measurement of the distance between the aortic bifurcation and the origin of the inferior mesenteric artery and that between the base of the inferior mesenteric artery and the origin of the left colic artery on integrated 3D imaging contributed to safe, prompt ligation of the vessels and excision of lymph nodes. Integrated 3D imaging with multislice CT was useful for simulation of laparoscopic colorectal surgery. (author)

  3. Accuracy and Precision of Three-Dimensional Low Dose CT Compared to Standard RSA in Acetabular Cups: An Experimental Study.

    Science.gov (United States)

    Brodén, Cyrus; Olivecrona, Henrik; Maguire, Gerald Q; Noz, Marilyn E; Zeleznik, Michael P; Sköldenberg, Olof

    2016-01-01

    Background and Purpose. The gold standard for detection of implant wear and migration is currently radiostereometry (RSA). The purpose of this study is to compare a three-dimensional computed tomography technique (3D CT) to standard RSA as an alternative technique for measuring migration of acetabular cups in total hip arthroplasty. Materials and Methods. With tantalum beads, we marked one cemented and one uncemented cup and mounted these on a similarly marked pelvic model. A comparison was made between 3D CT and standard RSA for measuring migration. Twelve repeated stereoradiographs and CT scans with double examinations in each position and gradual migration of the implants were made. Precision and accuracy of the 3D CT were calculated. Results. The accuracy of the 3D CT ranged between 0.07 and 0.32 mm for translations and 0.21 and 0.82° for rotation. The precision ranged between 0.01 and 0.09 mm for translations and 0.06 and 0.29° for rotations, respectively. For standard RSA, the precision ranged between 0.04 and 0.09 mm for translations and 0.08 and 0.32° for rotations, respectively. There was no significant difference in precision between 3D CT and standard RSA. The effective radiation dose of the 3D CT method, comparable to RSA, was estimated to be 0.33 mSv. Interpretation. Low dose 3D CT is a comparable method to standard RSA in an experimental setting.

  4. Computer graphic display of cardiac CT scans

    International Nuclear Information System (INIS)

    Palmer, R.; Carlsson, E.

    1982-01-01

    In order to improve spatial conception and quantitative assessment of the cardiac structures based on cardiac computed tomography, methods for computer graphic display were developed. Excised hearts and living dogs with myocardial infarctions were subjected to CT scanning. The data on the scanner tapes were processed to provide isodensity plots, linear section plots, time-weighted integrated isodensity plots as well as topographical density displays and three-dimensional spatial reconstructions of single and multi-layer scans. (orig.)

  5. Three-dimensional CT virtual endoscopy in the detection of simulated tumors in a novel phantom bladder and ureter model.

    Science.gov (United States)

    Russell, Shane T; Kawashima, Akira; Vrtiska, Terri J; LeRoy, Andrew J; Bruesewitz, Michael R; Hartman, Robert P; Slezak, Jeffrey M; McCollough, Cynthia H; Chow, George K; King, Bernard F

    2005-03-01

    Cystoscopy and ureteroscopy have limitations in the evaluation for urothelial tumors, and both are invasive. We studied the utility of three-dimensional (3D) CT virtual endoscopy in phantom models. A phantom pelvis was constructed of Plexiglas, porcine pelvic bones, and processed animal fat and scanned at various table speeds in a four detector-row CT machine for ability to detect "tumors" of Solidwater plastic polymer. Images were reconstructed at slice thicknesses of 2.5 to 5.0 mm and reconstructed in 3D for evaluation by two radiologists with no knowledge of the scanning parameters or tumor location. Similar studies were performed with a ureter model. With 5-mm slices, the sensitivity for bladder tumors ranged from 67% for 2-mm tumors to 100% for 4-mm tumors, with 12 false-positive findings. The overall sensitivity was 86% with 3.75-mm slices with one false positive, and with 2.5-mm slices, the sensitivity was 93%, again with one false positive. For the ureteral tumors, the overall sensitivities and numbers of false positives were 88.9% and eight with 5.0-mm collimation, 88.9% and four with 3.75-mm collimation, and 100% and three with 2.5-mm collimation. The effective radiation dose for all studies was equivalent to that of a standard abdomen/pelvis scan. Although virtual endoscopy traditionally has had difficulty detecting tumors <5 mm, the multidetector-row CT protocols used in this study could detect most lesions smaller than this. The scan also depicts the other tissues of the pelvis, which is valuable for staging. The 3D images were produced using data from the CT urogram parameters standard at our institution.

  6. Pediatric CT Scans

    Science.gov (United States)

    The Radiation Epidemiology Branch and collaborators have initiated a retrospective cohort study to evaluate the relationship between radiation exposure from CT scans conducted during childhood and adolescence and the subsequent development of cancer.

  7. Heart CT scan

    Science.gov (United States)

    ... make to decrease the risk of heart disease. Risks Risks of CT scans include: Being exposed to ... urac.org). URAC's accreditation program is an independent audit to verify that A.D.A.M. follows ...

  8. Optimal design and fabrication of three-dimensional calibration specimens for scanning probe microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Liu Xiaoning; Luo Tingting; Chen Yuhang; Huang Wenhao [Department of Precision Machinery and Instrumentation, University of Science and Technology of China, 230026 Hefei (China); Piaszenski, Guido [Raith GmbH, Konrad-Adenauer-Allee 8, 44263 Dortmund (Germany)

    2012-05-15

    Micro-/nano-scale roughness specimens are highly demanded to synthetically calibrate the scanning probe microscopy (SPM) instrument. In this study, three-dimensional (3D) specimens with controllable main surface evaluation parameters were designed. In order to improve the design accuracy, the genetic algorithm was introduced into the conventional digital filter method. A primary 3D calibration specimen with the dimension of 10 {mu}m x 10 {mu}m was fabricated by electron beam lithography. Atomic force microscopy characterizations demonstrated that the statistical and spectral parameters of the fabricated specimen match well with the designed values. Such a kind of 3D specimens has the potential to calibrate the SPM for applications in quantitative surface evaluations.

  9. Three-dimensional scanning force/tunneling spectroscopy at room temperature

    International Nuclear Information System (INIS)

    Sugimoto, Yoshiaki; Ueda, Keiichi; Abe, Masayuki; Morita, Seizo

    2012-01-01

    We simultaneously measured the force and tunneling current in three-dimensional (3D) space on the Si(111)-(7 × 7) surface using scanning force/tunneling microscopy at room temperature. The observables, the frequency shift and the time-averaged tunneling current were converted to the physical quantities of interest, i.e. the interaction force and the instantaneous tunneling current. Using the same tip, the local density of states (LDOS) was mapped on the same surface area at constant height by measuring the time-averaged tunneling current as a function of the bias voltage at every lateral position. LDOS images at negative sample voltages indicate that the tip apex is covered with Si atoms, which is consistent with the Si-Si covalent bonding mechanism for AFM imaging. A measurement technique for 3D force/current mapping and LDOS imaging on the equivalent surface area using the same tip was thus demonstrated. (paper)

  10. Three-dimensional CT examination of the mastication system in the giant anteater.

    Science.gov (United States)

    Endo, Hideki; Niizawa, Nobuharu; Komiya, Teruyuki; Kawada, Shinichiro; Kimura, Junpei; Itou, Takuya; Koie, Hiroshi; Sakai, Takeo

    2007-10-01

    The gross anatomy of the mastication system of the giant anteater (Myrmecophaga tridactyla) was examined by means of three-dimensional image analysis. The anteater rotates the mandibles medially and laterally to control its tongue when it is elongated and to house it when it is relaxed. Three-dimensional CT image analysis demonstrated that the shape and size of the oral cavity changes drastically when the mandibles are rotated. The oral cavity expands bilaterally when the dorsal part of the mandibles bend medially. Macroscopic observations and muscle-weight data supported the observation that the superficial temporal and medial pterygoid muscles act as the main medial and lateral rotators of the mandible, respectively. The low height of the mandibular ramus and the incomplete zygomatic arch in this species represent adaptations for the rotational movement of the mandibles, since they both contribute to the medially oriented transmission of force from the temporal muscles and to preventing collision between the mandibles and the cranium during the rotational movement.

  11. The usefulness of three-dimensional imaging with spiral CT in the evaluation of upper airway stenosis

    Energy Technology Data Exchange (ETDEWEB)

    Jang, Won Ho; Yoon, Dae Young; Bae, Sang Hoon; Rho, Young Soo; Jung, Yin Gyo [Hallym Univ. College of Medicine, Seoul (Korea, Republic of)

    1996-01-01

    To assess the usefulness of three-dimensional (3D) spiral CT imaging in patients with upper airway stenosis. We performed 3D spiral CT imagings in ten patients in whom upper airway stenosis was clinically suspected. Eight of these patients had upper airway stenosis caused by intubation or tracheostomy (n-6), tuberculosis (n=1), or extrinsic compression by a thyroid mass (n=1). Spiral CT scanning (30-second continuous exposure and 90-mm length) was performed with a table speed of 3mm/sec and a section thickness of 3mm. The selected starting point was the epiglottis. The resulting data were reformatted by multiplanar reformation (MPR) and shaded surface display (SSD) with peeling after reconstruction of 2mm interval. In the evaluation of location and extent of stenosis, we compared fidings of 3D imaging with those of baseline axial images (n=10), endoscopy (n=9) and operation (n=4). The locations of stenosis in eight patients were as follows;tracheostoma (n=4), subglottic region (n=3), and larynx (n=1). In all eight, 3D imaging demonstrated the location and extent of stenosis, which exactly correlated with endoscopic and operative findings. In one patient, however, another stenotic area in the tracheal bifurcation was not discovered because this lesion was not included in the field of CT scan. In two patients, the diagnosis on 3D images of no 'stenosis' was comfirmed by clinical findings or operation. No differences in diagnostic accuracy were noted between axial images, MPR, and SSD when evalvating the location and extent of stenosis; vertical extent was shown more easily by 3D imaging than by axial images, however. 3D imaging with spiral CT may be an useful adjunctive method in the evaluation of upper airway stenosis with variable causes.

  12. The usefulness of three-dimensional imaging with spiral CT in the evaluation of upper airway stenosis

    International Nuclear Information System (INIS)

    Jang, Won Ho; Yoon, Dae Young; Bae, Sang Hoon; Rho, Young Soo; Jung, Yin Gyo

    1996-01-01

    To assess the usefulness of three-dimensional (3D) spiral CT imaging in patients with upper airway stenosis. We performed 3D spiral CT imagings in ten patients in whom upper airway stenosis was clinically suspected. Eight of these patients had upper airway stenosis caused by intubation or tracheostomy (n-6), tuberculosis (n=1), or extrinsic compression by a thyroid mass (n=1). Spiral CT scanning (30-second continuous exposure and 90-mm length) was performed with a table speed of 3mm/sec and a section thickness of 3mm. The selected starting point was the epiglottis. The resulting data were reformatted by multiplanar reformation (MPR) and shaded surface display (SSD) with peeling after reconstruction of 2mm interval. In the evaluation of location and extent of stenosis, we compared fidings of 3D imaging with those of baseline axial images (n=10), endoscopy (n=9) and operation (n=4). The locations of stenosis in eight patients were as follows;tracheostoma (n=4), subglottic region (n=3), and larynx (n=1). In all eight, 3D imaging demonstrated the location and extent of stenosis, which exactly correlated with endoscopic and operative findings. In one patient, however, another stenotic area in the tracheal bifurcation was not discovered because this lesion was not included in the field of CT scan. In two patients, the diagnosis on 3D images of no 'stenosis' was comfirmed by clinical findings or operation. No differences in diagnostic accuracy were noted between axial images, MPR, and SSD when evalvating the location and extent of stenosis; vertical extent was shown more easily by 3D imaging than by axial images, however. 3D imaging with spiral CT may be an useful adjunctive method in the evaluation of upper airway stenosis with variable causes

  13. Three-dimensional quantitative CT of the proximal femur: Relationship to vertebral trabecular bone density

    International Nuclear Information System (INIS)

    Bhasin, S.; Zlatkin, M.B.; Sartoris, D.J.; Andre, M.; Resnick, D.

    1987-01-01

    Integrated cancellous, cortical, and total bone density in the femoral neck and inter-trochanteric region was measured bilaterally in 25 women aged 35-90 years (mean age, 65). Contiguous-section (1-cm-thick) data were analyzed using three-dimensional histogram software on a Cemax 1000 image processor. Single-section quantitative CT was used to determine mean mineral equivalent values for vertebral cancellous bone from T-11 to L-3 in each woman. Significant correlation was found between cancellous bone density at the two sites. Cortical and total bone densities in the proximal femur were predicted less well with vertebral cancellous data, suggesting a greater dependence on weight-bearing and activity factors

  14. Three dimensional reconstruction of fossils with X-ray CT and computer graphics

    Energy Technology Data Exchange (ETDEWEB)

    Hamada, Takashi; Tateno, Satoko (Tokyo Univ. (Japan). Coll. of Arts and Sciences); Suzuki, Naoki

    1991-12-01

    We have developed a method for three dimensional (3D) visualization of fossils such as trilobites and ammonites by non-destructive measurement and computer graphics. The imaging techniques in the medical sciences are applied for fossils by us to have quantitative data analyses on the structural and functional features of some extinct creatures. These methods are composed of a high resolutional X-ray computed tomography (X-ray CT) and computer graphics. We are able to observe not only outer shape but also inner structure of fossils as a 3D image by this method. Consequently, the shape and volume are measurable on these 3D image quantitatively. In addition to that, it is able to reconstruct an ideal figure from the deformed fossils by graphical treatments of the data. Such a 3D reconstruction method is useful to obtain a new information from the paleontological standpoint. (author).

  15. Three dimensional reconstruction of fossils with X-ray CT and computer graphics

    International Nuclear Information System (INIS)

    Hamada, Takashi; Tateno, Satoko; Suzuki, Naoki.

    1991-01-01

    We have developed a method for three dimensional (3D) visualization of fossils such as trilobites and ammonites by non-destructive measurement and computer graphics. The imaging techniques in the medical sciences are applied for fossils by us to have quantitative data analyses on the structural and functional features of some extinct creatures. These methods are composed of a high resolutional X-ray computed tomography (X-ray CT) and computer graphics. We are able to observe not only outer shape but also inner structure of fossils as a 3D image by this method. Consequently, the shape and volume are measurable on these 3D image quantitatively. In addition to that, it is able to reconstruct an ideal figure from the deformed fossils by graphical treatments of the data. Such a 3D reconstruction method is useful to obtain a new information from the paleontological standpoint. (author)

  16. Three-dimensional anatomical evaluation of bronchial artery with CT angiography

    International Nuclear Information System (INIS)

    Yu Hong; Li Huimin; Xiao Xiangsheng; Liu Shiyuan; Li Chengzhou; Tao Xiaofeng

    2006-01-01

    Objective: To evaluate the ability of CT angiography in identifying and demonstrating the origins and courses of bronchial arteries by using the three-dimensional reformation technique. Methods Four hundred and forty-three eases were examined with thin-section enhanced MSCT. Three-dimensional images of bronchial arteries were processed at the workstation. Spatial anatomical characters of the bronchial arteries using volume rendering(VR), muhiplanar reconstruction (MPR), and maxium intensity projection (MIP) were observed. Results: At least one bronchial artery was clearly displayed in VR in 359 eases. The right bronchial arteries mainly appeared to originate from the right intercostal artery (213/436, 48.85% ) and descending aorta (207/436, 47.48%), while the left bronchial arteries mainly from the descending aorta (363/371, 97.84%). The right bronchial arteries of the descending aorta were mainly arised from fight wall (95/207, 45.89%), and then the anterior wall (88/207, 42.51%), while the left bronchial arteries of the descending aorta mainly arised from anterior wall of the aorta (272/363, 74.93%). The common trunk originated from the descending aorta mainly positioned in the anterior wall (57/77, 74.03%). 49.31% (215/436) of the fight bronchial arteries were coursing across the posterior edge of the right main bronchi, 35.55% (155/436) coursing the inferior edge, while 60.11% (223/371) of left bronchial arteries coursing forward across the superior edger of the left main bronchi, the others coursing the inferior or the posterior edge. There were eleven bronchial artery distribution patterns, with the right and left ones predominating (192/359, 53.48%), and then two right and one left (63/359, 17.55%). Conclusion: The bronchial artery anatomy was complicated, and CT angiography could clearly visualize the features. (authors)

  17. Comparative Three-Dimensional Morphology of Baleen: Cross-Sectional Profiles and Volume Measurements Using CT Images.

    Science.gov (United States)

    Jensen, Megan M; Saladrigas, Amalia H; Goldbogen, Jeremy A

    2017-11-01

    Baleen whales are obligate filter feeders, straining prey-laden seawater through racks of keratinized baleen plates. Despite the importance of baleen to the ecology and natural history of these animals, relatively little work has been done on baleen morphology, particularly with regard to the three-dimensional morphology and structure of baleen. We used computed tomography (CT) scanning to take 3D images of six baleen specimens representing five species, including three complete racks. With these images, we described the three-dimensional shape of the baleen plates using cross-sectional profiles from within the gum tissue to the tip of the plates. We also measured the percentage of each specimen that was composed of either keratinized plate material or was void space between baleen plates, and thus available for seawater flow. Baleen plates have a complex three-dimensional structure with curvature that varies across the anterior-posterior, proximal-distal, and medial-lateral (lingual-labial) axes. These curvatures also vary with location along the baleen rack, and between species. Cross-sectional profiles resemble backwards-facing airfoils, and some specimens display S-shaped, or reflexed, camber. Within a baleen specimen, the intra-baleen void volume correlates with the average bristle diameter for a species, suggesting that essentially, thinner plates (with more space between them for flow) have thinner bristles. Both plate curvature and the relative proportions of plate and void volumes are likely to have implications for the mechanics of mysticete filtration, and future studies are needed to determine the particular functions of these morphological characters. Anat Rec, 300:1942-1952, 2017. © 2017 The Authors The Anatomical Record published by Wiley Periodicals, Inc. on behalf of American Association of Anatomists. © 2017 The Authors The Anatomical Record published by Wiley Periodicals, Inc. on behalf of American Association of Anatomists.

  18. Clinical application of the three-dimensional reconstruction of spiral CT pneumocolon

    International Nuclear Information System (INIS)

    Yu Shenping; Li Ziping; Xu Dasheng; Lin Erjian; Lin Peizhang; Xu Qiaolan

    2000-01-01

    Objective: To evaluate the clinical role of the 3 types of reconstruction of the spiral CT pneumocolon in the diagnosis of colon lesions. Methods: Three types of reconstruction with spiral CT pneumocolon including air cast imaging (ACI), CT virtual endoscopy (CTVE), and multiple planner reconstruction (MPR) in 34 patients with colorectal cancer or polyps were correlated with surgical pathology respectively. Results: Among the 34 patients, 30 was colorectal cancer and 6 was polyps (2 of which in the proximal lumen of 2 colon cancer). (1) Comparison between the 3 types of the spiral CT pneumocolon reconstruction and pathology in colorectal cancer. 1) ACI: tumor patterns: coincide (n =22), anti-coincide (n = 8); tumor extension: coincide (n = 24), anti-coincide (n = 6); tumor size: coincide (n = 28), anti-coincide (n = 2). 2) CTVE: tumor patterns: coincide (n = 26), anti-coincide (n = 4); tumor extension: coincide (n = 25), anti-coincide ( n 5); tumor size: coincide (n = 23), anti-coincide (n = 7). 3) MPR: tumor patterns: coincide (n = 24), anti-coincide (n = 6); tumor extension: coincide (n = 30), anti-coincide (n = 0); tumor size: coincide (n = 26), anti-coincide (n = 4). (2) Comparison between the 3 types of the spiral CT pneumocolon reconstruction and pathology in colorectal polyps: the lesions were displayed in 4 (ACI) and in 6 (CTVE and MPR). Conclusion: (1) For the diagnosis of colorectal cancers: CTVE was the best means to display the tumor patterns, MPR most correct to judge the tumor extension, and ACI most suitable to measure the tumor size. (2) For the diagnosis of colorectal polyps, ACI can be used for oriented diagnosis, CTVE can well display the intra-luminal three-dimensional structure and can be used for characteristic diagnosis, MPR can be used for differential diagnosis

  19. How many CT detector rows are necessary to perform adequate three dimensional visualization?

    International Nuclear Information System (INIS)

    Fischer, Lars; Tetzlaff, Ralf; Schoebinger, Max; Radeleff, Boris; Bruckner, Thomas; Meinzer, H.P.; Buechler, M.W.; Schemmer, Peter

    2010-01-01

    Introduction: The technical development of computer tomography (CT) imaging has experienced great progress. As consequence, CT data to be used for 3D visualization is not only based on 4 row CTs and 16 row CTs but also on 64 row CTs, respectively. The main goal of this study was to examine whether the increased amount of CT detector rows is correlated with improved quality of the 3D images. Material and Methods: All CTs were acquired during routinely performed preoperative evaluation. Overall, there were 12 data sets based on 4 detector row CT, 12 data sets based on 16 detector row CT, and 10 data sets based on 64 detector row CT. Imaging data sets were transferred to the DKFZ Heidelberg using the CHILI teleradiology system. For the analysis all CT scans were examined in a blinded fashion, i.e. both the name of the patient as well as the name of the CT brand were erased. For analysis, the time for segmentation of liver, both portal and hepatic veins as well as the branching depth of portal veins and hepatic veins was recorded automatically. In addition, all results were validated in a blinded fashion based on given quality index. Results: Segmentation of the liver was performed in significantly shorter time (p < 0.01, Kruskal-Wallis test) in the 16 row CT (median 479 s) compared to 4 row CT (median 611 s), and 64 row CT (median 670 s), respectively. The branching depth of the portal vein did not differ significantly among the 3 different data sets (p = 0.37, Kruskal-Wallis test). However, the branching depth of the hepatic veins was significantly better (p = 0.028, Kruskal-Wallis test) in the 4 row CT and 16 row CT compared to 64 row CT. The grading of the quality index was not statistically different for portal veins and hepatic veins (p = 0.80, Kruskal-Wallis test). Even though the total quality index was better for the vessel tree based on 64 row CT data sets (mean scale 2.6) compared to 4 CT row data (mean scale 3.25) and 16 row CT data (mean scale 3.0), these

  20. Efficacy of dynamic CT perfusion imaging in conjunction with three dimensional CT angiography for the evaluation of acute ischemic stroke

    Energy Technology Data Exchange (ETDEWEB)

    Nakaguchi, Hiroshi; Teraoka, Akira; Adachi, Shinobu; Yanagibashi, Kazutaka [Teraoka Memorial Hospital, Shinichi, Hiroshima (Japan)

    2003-01-01

    Through the use of a high-speed spiral CT scanner (GEMedical HiSpeedZX/i), CT/P/A technique, where conventional CT, CT perfusion imaging (CTP) and CT angiography (CTA) are consecutively performed, can now be performed with an imaging time of 90 seconds and a total contrast medium volume of 100 ml. A prospective clinical study was performed to ascertain the effectiveness of CT/P/A in diagnosing acute ischemic strokes. Twenty-nine consecutive patients of Teraoka Memorial Hospital suspected of suffering from the occlusion or constriction of cerebral arteries and who underwent CT/P/A within 3 hours from the onset served as subjects. The sensitivity, specificity, or Odds ratio of CTP and CTA in detecting lesions that caused cerebral infarction was calculated. CTP detected a hypoperfusion area with a sensitivity, specificity, and Odds ratio of 80%, 64%, and 7.2. The sensitivity in lobar infarcts, white matter infarcts, basal ganglia infarcts, and brainstem infarcts was 100%, 100%, 100%, 0% (p=0.0022). The sensitivity and Odds ratio of CT/P/A in cerebral infarcts differed according to the diameter of the infarcts. That with infarcts of 10 mm or more was 91%, 20. That with infarcts smaller than 10 mm was 50%, 2. CTA detected arterial lesions that caused cerebral ischemic attack with a sensitivity of 94% and specificity of 90%. The examination time for CT/P/A was 18 minutes, total radiation time being 90 seconds. Although CT/P/A was ineffective for the diagnosis of brainstem infarcts and lesions smaller than 10 mm, CT/P/A was useful in detecting moderate-sized hypoperfusion areas and arterial lesions three-dimensionally before an infarct is completed. (author)

  1. Scanning photoelectron microscope for nanoscale three-dimensional spatial-resolved electron spectroscopy for chemical analysis.

    Science.gov (United States)

    Horiba, K; Nakamura, Y; Nagamura, N; Toyoda, S; Kumigashira, H; Oshima, M; Amemiya, K; Senba, Y; Ohashi, H

    2011-11-01

    In order to achieve nondestructive observation of the three-dimensional spatially resolved electronic structure of solids, we have developed a scanning photoelectron microscope system with the capability of depth profiling in electron spectroscopy for chemical analysis (ESCA). We call this system 3D nano-ESCA. For focusing the x-ray, a Fresnel zone plate with a diameter of 200 μm and an outermost zone width of 35 nm is used. In order to obtain the angular dependence of the photoelectron spectra for the depth-profile analysis without rotating the sample, we adopted a modified VG Scienta R3000 analyzer with an acceptance angle of 60° as a high-resolution angle-resolved electron spectrometer. The system has been installed at the University-of-Tokyo Materials Science Outstation beamline, BL07LSU, at SPring-8. From the results of the line-scan profiles of the poly-Si/high-k gate patterns, we achieved a total spatial resolution better than 70 nm. The capability of our system for pinpoint depth-profile analysis and high-resolution chemical state analysis is demonstrated. © 2011 American Institute of Physics

  2. Three-dimensional three-component particle velocimetry for microscale flows using volumetric scanning

    International Nuclear Information System (INIS)

    Klein, S A; Moran, J L; Posner, J D; Frakes, D H

    2012-01-01

    We present a diagnostic platform for measuring three-dimensional three-component (3D3C) velocity fields in microscopic volumes. The imaging system uses high-speed Nipkow spinning disk confocal microscopy. Confocal microscopy provides optical sectioning using pinhole spatial filtering which rejects light originating from out-of-focus objects. The system accomplishes volumetric scanning by rapid translation of the high numerical aperture objective using a piezo objective positioner. The motion of fluorescent microspheres is quantified using 3D3C super resolution particle-imaging velocimetry with instantaneous spatial resolutions of the order of 5 µm or less in all three dimensions. We examine 3D3C flow in a PDMS microchannel with an expanding section at 3D acquisition rates of 30 Hz, and find strong agreement with a computational model. Equations from the PIV and PTV literature adapted for a scanning objective provide estimates of maximum measurable velocity. The technique allows for isosurface visualization of 3D particle motion and robust high spatial resolution velocity measurements without requiring a calibration step or reconstruction algorithms. (paper)

  3. Clinical applications for multiplanar- and three-dimensional-reconstructions by helical-CT for the diagnosis of acetabular fractures

    International Nuclear Information System (INIS)

    Stroszczynski, C.; Schedel, H.; Stoeckle, U.; Wellmann, A.; Beier, J.; Wicht, L.; Hoffmann, R.; Felix, R.

    1996-01-01

    This review describes recent visualizations of computed tomography for the diagnosis of acetabular fractures. The techniques of conventional and helical-CT for the imaging of the acetabulum are compared. Furthermore, the different methods of multiplaner and three-dimensional reconstructions e.g. shaded surface display, maximum intensity projection, and volume rendering are presented. Figures of multiplanar and three-dimensional imaging for fractures of the pelvis is discussed. (orig.) [de

  4. Three-dimensional CT pyelography for planning of percutaneous nephrostolithotomy: accuracy of stone measurement, stone depiction and pelvicalyceal reconstruction

    Energy Technology Data Exchange (ETDEWEB)

    Patel, Uday [St George' s Hospital and Medical School, Department of Radiology, London (United Kingdom); Princess Grace Hospital, London (United Kingdom); Walkden, Richard Miles [St George' s Hospital and Medical School, Department of Radiology, London (United Kingdom); Ghani, Khurshid R. [St George' s Hospital and Medical School, Department of Urology, London (United Kingdom); Anson, Ken [St George' s Hospital and Medical School, Department of Urology, London (United Kingdom); Princess Grace Hospital, London (United Kingdom)

    2009-05-15

    Retrospective evaluation of computed tomographic (CT) pyelography before percutaneous nephrostolithotomy (PCNL). Twenty patients with renal calculi underwent CT pyelography using a dedicated protocol. Calculus size, uniformity of contrast excretion and accuracy of calculus and pelvicalyceal (PC) system reconstructions were scored and compared on axial and coronal maximum intensity projections (MIP) and volume reconstructions (VRmovie loops). After contrast medium administration, the size of calculi is accurate on axial images, but underestimated on coronal studies: mean 14.7 mm vs. 14.4 mm (axial) and 17.2 mm vs. 16.1 mm (coronal) for measurements before and after enhancement, respectively (p = 0.11 and 0.03). Uniform contrast medium excretion (median 228 HU; 95% CI 209-266 HU) was sufficiently lower than calculus density (median 845 HU; 95% CI 457-1,193 HU) for precise calculus and pelvicalyceal reconstructions in 87% and 85%, respectively. Coronal MIP scans were rated best for calculus depiction (mean score 2.68 vs. 2.50 and 2.41 for coronal, axial and VRs, respectively; p = 0.14) and VR studies best for PC anatomy (mean score 4.4 vs. 3.73 and 2.89 for VR, coronal and axial studies, respectively; p = <0.0001). Three-dimensional CT pyelography can accurately demonstrate calculus position and spatial relationships of the collecting system before PCNL. (orig.)

  5. Three-dimensional CT pyelography for planning of percutaneous nephrostolithotomy: accuracy of stone measurement, stone depiction and pelvicalyceal reconstruction

    International Nuclear Information System (INIS)

    Patel, Uday; Walkden, Richard Miles; Ghani, Khurshid R.; Anson, Ken

    2009-01-01

    Retrospective evaluation of computed tomographic (CT) pyelography before percutaneous nephrostolithotomy (PCNL). Twenty patients with renal calculi underwent CT pyelography using a dedicated protocol. Calculus size, uniformity of contrast excretion and accuracy of calculus and pelvicalyceal (PC) system reconstructions were scored and compared on axial and coronal maximum intensity projections (MIP) and volume reconstructions (VRmovie loops). After contrast medium administration, the size of calculi is accurate on axial images, but underestimated on coronal studies: mean 14.7 mm vs. 14.4 mm (axial) and 17.2 mm vs. 16.1 mm (coronal) for measurements before and after enhancement, respectively (p = 0.11 and 0.03). Uniform contrast medium excretion (median 228 HU; 95% CI 209-266 HU) was sufficiently lower than calculus density (median 845 HU; 95% CI 457-1,193 HU) for precise calculus and pelvicalyceal reconstructions in 87% and 85%, respectively. Coronal MIP scans were rated best for calculus depiction (mean score 2.68 vs. 2.50 and 2.41 for coronal, axial and VRs, respectively; p = 0.14) and VR studies best for PC anatomy (mean score 4.4 vs. 3.73 and 2.89 for VR, coronal and axial studies, respectively; p = <0.0001). Three-dimensional CT pyelography can accurately demonstrate calculus position and spatial relationships of the collecting system before PCNL. (orig.)

  6. Validation of phalanx bone three-dimensional surface segmentation from computed tomography images using laser scanning

    Energy Technology Data Exchange (ETDEWEB)

    DeVries, Nicole A.; Gassman, Esther E.; Kallemeyn, Nicole A. [The University of Iowa, Department of Biomedical Engineering, Center for Computer Aided Design, Iowa City, IA (United States); Shivanna, Kiran H. [The University of Iowa, Center for Computer Aided Design, Iowa City, IA (United States); Magnotta, Vincent A. [The University of Iowa, Department of Biomedical Engineering, Department of Radiology, Center for Computer Aided Design, Iowa City, IA (United States); Grosland, Nicole M. [The University of Iowa, Department of Biomedical Engineering, Department of Orthopaedics and Rehabilitation, Center for Computer Aided Design, Iowa City, IA (United States)

    2008-01-15

    To examine the validity of manually defined bony regions of interest from computed tomography (CT) scans. Segmentation measurements were performed on the coronal reformatted CT images of the three phalanx bones of the index finger from five cadaveric specimens. Two smoothing algorithms (image-based and Laplacian surface-based) were evaluated to determine their ability to represent accurately the anatomic surface. The resulting surfaces were compared with laser surface scans of the corresponding cadaveric specimen. The average relative overlap between two tracers was 0.91 for all bones. The overall mean difference between the manual unsmoothed surface and the laser surface scan was 0.20 mm. Both image-based and Laplacian surface-based smoothing were compared; the overall mean difference for image-based smoothing was 0.21 mm and 0.20 mm for Laplacian smoothing. This study showed that manual segmentation of high-contrast, coronal, reformatted, CT datasets can accurately represent the true surface geometry of bones. Additionally, smoothing techniques did not significantly alter the surface representations. This validation technique should be extended to other bones, image segmentation and spatial filtering techniques. (orig.)

  7. Validation of phalanx bone three-dimensional surface segmentation from computed tomography images using laser scanning

    International Nuclear Information System (INIS)

    DeVries, Nicole A.; Gassman, Esther E.; Kallemeyn, Nicole A.; Shivanna, Kiran H.; Magnotta, Vincent A.; Grosland, Nicole M.

    2008-01-01

    To examine the validity of manually defined bony regions of interest from computed tomography (CT) scans. Segmentation measurements were performed on the coronal reformatted CT images of the three phalanx bones of the index finger from five cadaveric specimens. Two smoothing algorithms (image-based and Laplacian surface-based) were evaluated to determine their ability to represent accurately the anatomic surface. The resulting surfaces were compared with laser surface scans of the corresponding cadaveric specimen. The average relative overlap between two tracers was 0.91 for all bones. The overall mean difference between the manual unsmoothed surface and the laser surface scan was 0.20 mm. Both image-based and Laplacian surface-based smoothing were compared; the overall mean difference for image-based smoothing was 0.21 mm and 0.20 mm for Laplacian smoothing. This study showed that manual segmentation of high-contrast, coronal, reformatted, CT datasets can accurately represent the true surface geometry of bones. Additionally, smoothing techniques did not significantly alter the surface representations. This validation technique should be extended to other bones, image segmentation and spatial filtering techniques. (orig.)

  8. Reporducibilities of cephalometric measurements of three-dimensional CT images reconstructed in the personal computer

    Energy Technology Data Exchange (ETDEWEB)

    Jeon, Kug Jin; Park, Hyok; Lee, Hee Cheol; Kim, Kee Deog; Park, Chang Seo [Yonsei University College of Medicine, Seoul (Korea, Republic of)

    2003-09-15

    The purpose of this study was to report the reproducibility of intra-observer and inter-observer consistency of cephalometric measurements using three-dimensional (3D) computed tomography (CT), and the degree of difference of the cephalometric measurements. CT images of 16 adult patients with normal class I occlusion were sent to personal computer and reconstructed into 3D images using V-Works 3.5{sup TM} (Cybermed Inc., Seoul, Korea). With the internal program of V-Works 3.5{sup TM}, 12 landmarks on regular cephalograms were transformed into 21 analytic categories and measured by 2 observers and in addition, one of the observers repeated their measurements. Intra-observer difference was calculated using paired t-test, and inter-observer by two sample test. There were significant differences in the intra-observer measurements (p<0.05) in four of the categories which included ANS-Me, ANS-PNS, Cdl-GO (Lt), GoL-GoR, but with the exception of Cdl-Go (Lt), ZmL-ZmR, Zyo-Zyo, the average differences were within 2 mm of each other. The inter-observer observations also showed significant differences in the measurements of the ZmL-ZmR and Zyo-Zyo categories (p<0.05). With the exception of the Cdl-Me (Rt), ZmL-ZmR, Zyo-Zyo categories, the average differences between the two observers were within 2mm, but the ZmL-ZmR and Zyo-Zyo values differed greatly with values of 8.10 and 19.8 mm respectively. In general, 3D CT images showed greater accuracy and reproducibility, with the exception of suture areas such as Zm and Zyo, than regular cephalograms in orthodontic measurement, showing differences of less than 2 mm, therefore 3D CT images can be useful in cephalometric measurements and treatment planning.

  9. Dynamic evaluation of pelvic floor reconstructive surgery using radiopaque meshes and three-dimensional helical CT

    Directory of Open Access Journals (Sweden)

    Paulo Palma

    2010-04-01

    Full Text Available PURPOSE: This prospective study was performed to achieve visualization of the reestablishment of anatomy after reconstructive surgery in the different pelvic compartments with non-absorbable radiopaque meshes, providing valuable anatomic information for surgeons implanting meshes. MATERIALS AND METHODS: A total of 30 female patients with stress urinary incontinence (SUI, anterior and posterior vaginal wall prolapse, or both underwent surgical repair using radiopaque meshes after written informed consent. Patients with SUI underwent five different surgeries. Patients with anterior vaginal prolapse underwent a procedure using a combined pre-pubic and transobturator mesh, and those with posterior vaginal prolapse underwent posterior slingplasty. Three-dimensional reconstruction using helical CT was performed four weeks postoperatively. RESULTS: In all cases, the mesh was clearly visualized. Transobturator slings were shown at the midurethra, and the anchoring tails perforated the obturator foramen at the safety region. Mini-slings were in the proper place, and computed angiography revealed that the anchoring system was away from the obturator vessels. In patients undergoing procedure for anterior vaginal prolapse, both pre-pubic armpit and obturator slings were clearly seen and the mesh was in the proper position, supporting the bladder base and occluding the distal part of the urogenital hiatus. Transcoccygeal sacropexy revealed indirectly a well-supported "neo rectovaginal fascia" and the anchoring tails at the level of ischial spines. CONCLUSION: Three-dimensional helical tomography images of the female pelvis using radiopaque meshes have a potential role in improving our understanding of pelvic floor reconstructive surgeries. These radiopaque meshes might be the basis of a new investigative methodology.

  10. Three-dimensional imaging of porous media using confocal laser scanning microscopy.

    Science.gov (United States)

    Shah, S M; Crawshaw, J P; Boek, E S

    2017-02-01

    In the last decade, imaging techniques capable of reconstructing three-dimensional (3-D) pore-scale model have played a pivotal role in the study of fluid flow through complex porous media. In this study, we present advances in the application of confocal laser scanning microscopy (CLSM) to image, reconstruct and characterize complex porous geological materials with hydrocarbon reservoir and CO 2 storage potential. CLSM has a unique capability of producing 3-D thin optical sections of a material, with a wide field of view and submicron resolution in the lateral and axial planes. However, CLSM is limited in the depth (z-dimension) that can be imaged in porous materials. In this study, we introduce a 'grind and slice' technique to overcome this limitation. We discuss the practical and technical aspects of the confocal imaging technique with application to complex rock samples including Mt. Gambier and Ketton carbonates. We then describe the complete workflow of image processing to filtering and segmenting the raw 3-D confocal volumetric data into pores and grains. Finally, we use the resulting 3-D pore-scale binarized confocal data obtained to quantitatively determine petrophysical pore-scale properties such as total porosity, macro- and microporosity and single-phase permeability using lattice Boltzmann (LB) simulations, validated by experiments. © 2016 The Authors Journal of Microscopy © 2016 Royal Microscopical Society.

  11. Three-Dimensional (3D) Nanometrology Based on Scanning Electron Microscope (SEM) Stereophotogrammetry.

    Science.gov (United States)

    Tondare, Vipin N; Villarrubia, John S; Vlada R, András E

    2017-10-01

    Three-dimensional (3D) reconstruction of a sample surface from scanning electron microscope (SEM) images taken at two perspectives has been known for decades. Nowadays, there exist several commercially available stereophotogrammetry software packages. For testing these software packages, in this study we used Monte Carlo simulated SEM images of virtual samples. A virtual sample is a model in a computer, and its true dimensions are known exactly, which is impossible for real SEM samples due to measurement uncertainty. The simulated SEM images can be used for algorithm testing, development, and validation. We tested two stereophotogrammetry software packages and compared their reconstructed 3D models with the known geometry of the virtual samples used to create the simulated SEM images. Both packages performed relatively well with simulated SEM images of a sample with a rough surface. However, in a sample containing nearly uniform and therefore low-contrast zones, the height reconstruction error was ≈46%. The present stereophotogrammetry software packages need further improvement before they can be used reliably with SEM images with uniform zones.

  12. A proposal of a three-dimensional CT measurement method of maxillofacial structure

    International Nuclear Information System (INIS)

    Tanaka, Ray; Hayashi, Takafumi

    2007-01-01

    Three-dimensional CT measurement is put in practice in order to grasp the pathological condition on diseases such as the temporomandibular joint disorder, maxillofacial anomaly, jaw deformity, or fracture which cause the morphologic changes of the maxillofacial bones. On the 3D measurement, the unique system that is obtained by volume rendering 3D images with a simultaneous reference of axial images combined with coronal and sagittal multi-planar reconstruction (MPR) images (we call this MPR referential method), is employed in order to define the measurement points. Our purpose in this report is to indicate the usefulness of this unique method by comparing with the common way to define the measurement points on only 3D reconstruction images without consulting of MPR images. Clinical CT data obtained from a male patient with skeletal malocclusion was used. Contiguous axial images were reconstructed at 4 times magnification, with a reconstruction interval of 0.5 mm, focused on the temporomandibular joint region in his left side. After these images were converted to Digital Imaging and Communications in Medicine (DICOM) format and sent to personal computer (PC), 3D reconstruction image was created using free 3D DICOM medical image viewer. The coordinates of 3 measurement points (the lateral and medial pole of the mandibular condyle, and the left foramen ovale) were defined with MPR images (MPR coordinates) as reference coordinates, and then the coordinates that were defined on only 3D reconstruction image without consulting to MPR images (3D coordinates) were compared to those of MPR coordinates. Three examiners were engaged independently 10 times for every measurement point. In our result, there was no correspondence between 3D coordinates and MPR coordinates, and contribution of 3D coordinates showed a variety in every measurement point and in every observer. We deemed that ''MPR referential method'' is useful to assess the location of the target point of anatomical

  13. Three-dimensional hard and soft tissue imaging of the human cochlea by scanning laser optical tomography (SLOT.

    Directory of Open Access Journals (Sweden)

    Nadine Tinne

    Full Text Available The present study focuses on the application of scanning laser optical tomography (SLOT for visualization of anatomical structures inside the human cochlea ex vivo. SLOT is a laser-based highly efficient microscopy technique which allows for tomographic imaging of the internal structure of transparent specimens. Thus, in the field of otology this technique is best convenient for an ex vivo study of the inner ear anatomy. For this purpose, the preparation before imaging comprises decalcification, dehydration as well as optical clearing of the cochlea samples in toto. Here, we demonstrate results of SLOT imaging visualizing hard and soft tissue structures with an optical resolution of down to 15 μm using extinction and autofluorescence as contrast mechanisms. Furthermore, the internal structure can be analyzed nondestructively and quantitatively in detail by sectioning of the three-dimensional datasets. The method of X-ray Micro Computed Tomography (μCT has been previously applied to explanted cochlea and is solely based on absorption contrast. An advantage of SLOT is that it uses visible light for image formation and thus provides a variety of contrast mechanisms known from other light microscopy techniques, such as fluorescence or scattering. We show that SLOT data is consistent with μCT anatomical data and provides additional information by using fluorescence. We demonstrate that SLOT is applicable for cochlea with metallic cochlear implants (CI that would lead to significant artifacts in μCT imaging. In conclusion, the present study demonstrates the capability of SLOT for resolution visualization of cleared human cochleae ex vivo using multiple contrast mechanisms and lays the foundation for a broad variety of additional studies.

  14. Multimodal registration of three-dimensional maxillodental cone beam CT and photogrammetry data over time.

    Science.gov (United States)

    Bolandzadeh, N; Bischof, W; Flores-Mir, C; Boulanger, P

    2013-01-01

    In recent years, one of the foci of orthodontics has been on systems for the evaluation of treatment results and the tracking of tissue variations over time. This can be accomplished through analysing three-dimensional orthodontic images obtained before and after the treatments. Since complementary information is achieved by integrating multiple imaging modalities, cone beam CT (CBCT) and stereophotogrammetry technologies are used in this study to develop a method for tracking bone, teeth and facial soft-tissue variations over time. We propose a two-phase procedure of multimodal (Phase 1) and multitemporal (Phase 2) registration which aligns images taken from the same patient by different imaging modalities and at different times. Extrinsic (for Phase 1) and intrinsic (for Phase 2) landmark-based registration methods are employed as an initiation for a robust iterative closest points algorithm. Since the mandible moves independently of the upper skull, the registration procedure is applied separately on the mandible and the upper skull. The results show that the signed error distributions of both mandible and skull registrations follow a mixture of two Gaussian distributions, corresponding to alignment errors (due to our method) and temporal change over time. We suggest that the large values among the total registration errors correspond to the temporal change resulting from (1) the effect of treatment (i.e. the orthodontic changes of teeth positions); (2) the biological changes such as teeth growth over time, especially for teenagers; and (3) the segmentation procedure and CBCT precision change over time.

  15. Three-dimensional focus of attention for iterative cone-beam micro-CT reconstruction

    International Nuclear Information System (INIS)

    Benson, T M; Gregor, J

    2006-01-01

    Three-dimensional iterative reconstruction of high-resolution, circular orbit cone-beam x-ray CT data is often considered impractical due to the demand for vast amounts of computer cycles and associated memory. In this paper, we show that the computational burden can be reduced by limiting the reconstruction to a small, well-defined portion of the image volume. We first discuss using the support region defined by the set of voxels covered by all of the projection views. We then present a data-driven preprocessing technique called focus of attention that heuristically separates both image and projection data into object and background before reconstruction, thereby further reducing the reconstruction region of interest. We present experimental results for both methods based on mouse data and a parallelized implementation of the SIRT algorithm. The computational savings associated with the support region are substantial. However, the results for focus of attention are even more impressive in that only about one quarter of the computer cycles and memory are needed compared with reconstruction of the entire image volume. The image quality is not compromised by either method

  16. Evaluation of gastric carcinoma with CT three-dimensional imaging compared with conventional barium study

    International Nuclear Information System (INIS)

    Ju Shenghong; Chen Feng; Zheng Kai'er; Sun Jun

    2002-01-01

    Objective: To assess the role of three-dimensional (3D) CT imaging including CT virtual gastroscopy (CTVG), surface-shaded display (SSD), and Raysum Display in the evaluation of gastric carcinoma compared with upper gastrointestinal series (UGI). Methods: In 43 histologically proved gastric carcinoma patients (37 advanced gastric carcinomas and 6 early gastric carcinomas), the results of CTVG and 3D CT imaging were compared to that of UGI. Two observers blindly evaluated images with all four techniques in terms of image quality, artifacts, diagnostic confidence, and Borrmann classification. Sensitivities of lesion detection and classification based on Borrmann classification of CTVG and 3D CT were determined by comparing them to surgical and histological findings. Results: The lesion detection sensitivity of CTVG, SSD, Raysum, and UGI by two observers were 98%, 67%, 60% and 84%, and 98%, 70%, 70% and 88%, respectively. The Borrmann's classification sensitivity by two observers were 76%, 49%, 38% and 49%, and 78%, 51%, 35% and 43%, respectively. Overall image quality of CTVG, SSD, and Raysum was considered similar to that of UGI by both observers (P>0.05). There was no statistical significant difference for advanced lesion (with diagnostic confidence of 3 or above) in detection sensitivity between CTVG and UGI (χ 2 = 0.50 and 0.25, P>0.05), but the lesion detection sensitivity of SSD and Raysum display were lower than that of UGI (χ 2 4.17, 7.11 and 5.14, 4.17, P 2 = 4.90 and 4.92, P 2 = 2.25, P > 0.05). Excess fluid remained in the stomach and patient respiratory movement during breath holds were the reasons causing severe artifacts (6.1%) that influenced the diagnostic evaluation. Conclusion: The performance of CTVG was equivalent to UGI in the Borrmann's classification. CTVG has potential in the detection of early gastric carcinoma. The value of SSD and Raysum display was limited in the evaluation of gastric carcinoma when used alone clinically

  17. A comparison of primary two- and three-dimensional methods to review CT colonography

    International Nuclear Information System (INIS)

    Gelder, Rogier E. van; Florie, Jasper; Nio, C. Yung; Jager, Steven W. de; Lameris, Johan S.; Stoker, Jaap; Jensch, Sebastiaan; Vos, Frans M.; Venema, Henk W.; Bartelsman, Joep F.; Reitsma, Johannes B.; Bossuyt, Patrick M.M.

    2007-01-01

    The aim of our study was to compare primary three-dimensional (3D) and primary two-dimensional (2D) review methods for CT colonography with regard to polyp detection and perceptive errors. CT colonography studies of 77 patients were read twice by three reviewers, first with a primary 3D method and then with a primary 2D method. Mean numbers of true and false positives, patient sensitivity and specificity and perceptive errors were calculated with colonoscopy as a reference standard. A perceptive error was made if a polyp was not detected by all reviewers. Mean sensitivity for large (≥10 mm) polyps for primary 3D and 2D review was 81% (14.7/18) and 70%(12.7/18), respectively (p-values ≥0.25). Mean numbers of large false positives for primary 3D and 2D were 8.3 and 5.3, respectively. With primary 3D and 2D review 1 and 6 perceptive errors, respectively, were made in 18 large polyps (p = 0.06). For medium-sized (6-9 mm) polyps these values were for primary 3D and 2D, respectively: mean sensitivity: 67%(11.3/17) and 61%(10.3/17; p-values≥ 0.45), number of false positives: 33.3 and 15.6, and perceptive errors: 4 and 6 (p = 0.53). No significant differences were found in the detection of large and medium-sized polyps between primary 3D and 2D review. (orig.)

  18. Modeling Vehicle Collision Angle in Traffic Crashes Based on Three-Dimensional Laser Scanning Data

    Directory of Open Access Journals (Sweden)

    Nengchao Lyu

    2017-02-01

    Full Text Available In road traffic accidents, the analysis of a vehicle’s collision angle plays a key role in identifying a traffic accident’s form and cause. However, because accurate estimation of vehicle collision angle involves many factors, it is difficult to accurately determine it in cases in which less physical evidence is available and there is a lack of monitoring. This paper establishes the mathematical relation model between collision angle, deformation, and normal vector in the collision region according to the equations of particle deformation and force in Hooke’s law of classical mechanics. At the same time, the surface reconstruction method suitable for a normal vector solution is studied. Finally, the estimation model of vehicle collision angle is presented. In order to verify the correctness of the model, verification of multi-angle collision experiments and sensitivity analysis of laser scanning precision for the angle have been carried out using three-dimensional (3D data obtained by a 3D laser scanner in the collision deformation zone. Under the conditions with which the model has been defined, validation results show that the collision angle is a result of the weighted synthesis of the normal vector of the collision point and the weight value is the deformation of the collision point corresponding to normal vectors. These conclusions prove the applicability of the model. The collision angle model proposed in this paper can be used as the theoretical basis for traffic accident identification and cause analysis. It can also be used as a theoretical reference for the study of the impact deformation of elastic materials.

  19. Three-dimensional structure of wind turbine wakes as measured by scanning lidar

    Science.gov (United States)

    Bodini, Nicola; Zardi, Dino; Lundquist, Julie K.

    2017-08-01

    The lower wind speeds and increased turbulence that are characteristic of turbine wakes have considerable consequences on large wind farms: turbines located downwind generate less power and experience increased turbulent loads. The structures of wakes and their downwind impacts are sensitive to wind speed and atmospheric variability. Wake characterization can provide important insights for turbine layout optimization in view of decreasing the cost of wind energy. The CWEX-13 field campaign, which took place between June and September 2013 in a wind farm in Iowa, was designed to explore the interaction of multiple wakes in a range of atmospheric stability conditions. Based on lidar wind measurements, we extend, present, and apply a quantitative algorithm to assess wake parameters such as the velocity deficits, the size of the wake boundaries, and the location of the wake centerlines. We focus on wakes from a row of four turbines at the leading edge of the wind farm to explore variations between wakes from the edge of the row (outer wakes) and those from turbines in the center of the row (inner wakes). Using multiple horizontal scans at different elevations, a three-dimensional structure of wakes from the row of turbines can be created. Wakes erode very quickly during unstable conditions and can in fact be detected primarily in stable conditions in the conditions measured here. During stable conditions, important differences emerge between the wakes of inner turbines and the wakes of outer turbines. Further, the strong wind veer associated with stable conditions results in a stretching of the wake structures, and this stretching manifests differently for inner and outer wakes. These insights can be incorporated into low-order wake models for wind farm layout optimization or for wind power forecasting.

  20. Standardization of MIP technique in three-dimensional CT portography: usefulness in evaluation of portosystemic collaterals in cirrhotic patients

    International Nuclear Information System (INIS)

    Kim, Jong Gi; Kim, Yong; Kim, Chang Won; Lee, Jun Woo; Lee, Suk Hong

    2003-01-01

    To assess the usefulness of three-dimensional CT portography using a standardized maximum intensity projection (MIP) technique for the evaluation of portosystemic collaterals in cirrhotic patients. In 25 cirrhotic patients with portosystemic collaterals, three-phase CT using a multide-tector-row helical CT scanner was performed to evaluate liver disease. Late arterial-phase images were transferred to an Advantage Windows 3.1 workstation (Gener Electric). Axial images were reconstructed by means of three-dimensional CT portography, using both a standardized and a non-standardized MIP technique, and the respective reconstruction times were determined. Three-dimensional CT portography with the standardized technique involved eight planes, namely the spleno-portal confluence axis (coronal, lordotic coronal, lordotic coronal RAO 30 .deg. C, and lordotic coronal LAO 30 .deg. C), the left renal vein axis (lordotic coronal), and axial MIP images (lower esophagus level, gastric fundus level and splenic hilum). The eight MIP images obtained in each case were interpreted by two radiologists, who reached a consensus in their evaluation. The portosystemic collaterals evaluated were as follows: left gastric vein dilatation; esophageal, paraesophageal, gastric, and splenic varix; paraumbilical vein dilatation; gastro-renal, spleno-renal, and gastro-spleno-renal shunt; mesenteric, retroperitoneal, and omental collaterals. The average reconstruction time using the non-standardized MIP technique was 11 minutes 23 seconds, and with the standardized technique, the time was 6 minutes 5 seconds. Three-dimensional CT portography with the standardized technique demonstrated left gastric vein dilatation (n=25), esophageal varix (n=18), paraesophageal varix (n=13), gastric varix (n=4), splenic varix (n=4), paraumbilical vein dilatation (n=4), gastro-renal shunt (n=3), spleno-renal shunt (n=3), and gastro-spleno-renal shunt (n=1). Using three-dimensional CT protography and the non

  1. Three dimensional dose distribution comparison of simple and complex acquisition trajectories in dedicated breast CT

    Energy Technology Data Exchange (ETDEWEB)

    Shah, Jainil P., E-mail: jainil.shah@duke.edu [Department of Biomedical Engineering, Duke University, Durham, North Carolina 27705 and Multi Modality Imaging Lab, Duke University Medical Center, Durham, North Carolina 27710 (United States); Mann, Steve D. [Medical Physics Graduate Program, Duke University Medical Center, Durham, North Carolina 27705 and Multi Modality Imaging Lab, Duke University Medical Center, Durham, North Carolina 27710 (United States); McKinley, Randolph L. [ZumaTek, Inc., Research Triangle Park, North Carolina 27709 (United States); Tornai, Martin P. [Department of Biomedical Engineering, Duke University, Durham, North Carolina 27705 (United States); Medical Physics Graduate Program, Duke University Medical Center, Durham, North Carolina 27705 (United States); Multi Modality Imaging Lab, Duke University Medical Center, Durham, North Carolina 27710 (United States)

    2015-08-15

    Purpose: A novel breast CT system capable of arbitrary 3D trajectories has been developed to address cone beam sampling insufficiency as well as to image further into the patient’s chest wall. The purpose of this study was to characterize any trajectory-related differences in 3D x-ray dose distribution in a pendant target when imaged with different orbits. Methods: Two acquisition trajectories were evaluated: circular azimuthal (no-tilt) and sinusoidal (saddle) orbit with ±15° tilts around a pendant breast, using Monte Carlo simulations as well as physical measurements. Simulations were performed with tungsten (W) filtration of a W-anode source; the simulated source flux was normalized to the measured exposure of a W-anode source. A water-filled cylindrical phantom was divided into 1 cm{sup 3} voxels, and the cumulative energy deposited was tracked in each voxel. Energy deposited per voxel was converted to dose, yielding the 3D distributed dose volumes. Additionally, three cylindrical phantoms of different diameters (10, 12.5, and 15 cm) and an anthropomorphic breast phantom, initially filled with water (mimicking pure fibroglandular tissue) and then with a 75% methanol-25% water mixture (mimicking 50–50 fibroglandular-adipose tissues), were used to simulate the pendant breast geometry and scanned on the physical system. Ionization chamber calibrated radiochromic film was used to determine the dose delivered in a 2D plane through the center of the volume for a fully 3D CT scan using the different orbits. Results: Measured experimental results for the same exposure indicated that the mean dose measured throughout the central slice for different diameters ranged from 3.93 to 5.28 mGy, with the lowest average dose measured on the largest cylinder with water mimicking a homogeneously fibroglandular breast. These results align well with the cylinder phantom Monte Carlo studies which also showed a marginal difference in dose delivered by a saddle trajectory in the

  2. Three dimensional dose distribution comparison of simple and complex acquisition trajectories in dedicated breast CT

    International Nuclear Information System (INIS)

    Shah, Jainil P.; Mann, Steve D.; McKinley, Randolph L.; Tornai, Martin P.

    2015-01-01

    Purpose: A novel breast CT system capable of arbitrary 3D trajectories has been developed to address cone beam sampling insufficiency as well as to image further into the patient’s chest wall. The purpose of this study was to characterize any trajectory-related differences in 3D x-ray dose distribution in a pendant target when imaged with different orbits. Methods: Two acquisition trajectories were evaluated: circular azimuthal (no-tilt) and sinusoidal (saddle) orbit with ±15° tilts around a pendant breast, using Monte Carlo simulations as well as physical measurements. Simulations were performed with tungsten (W) filtration of a W-anode source; the simulated source flux was normalized to the measured exposure of a W-anode source. A water-filled cylindrical phantom was divided into 1 cm"3 voxels, and the cumulative energy deposited was tracked in each voxel. Energy deposited per voxel was converted to dose, yielding the 3D distributed dose volumes. Additionally, three cylindrical phantoms of different diameters (10, 12.5, and 15 cm) and an anthropomorphic breast phantom, initially filled with water (mimicking pure fibroglandular tissue) and then with a 75% methanol-25% water mixture (mimicking 50–50 fibroglandular-adipose tissues), were used to simulate the pendant breast geometry and scanned on the physical system. Ionization chamber calibrated radiochromic film was used to determine the dose delivered in a 2D plane through the center of the volume for a fully 3D CT scan using the different orbits. Results: Measured experimental results for the same exposure indicated that the mean dose measured throughout the central slice for different diameters ranged from 3.93 to 5.28 mGy, with the lowest average dose measured on the largest cylinder with water mimicking a homogeneously fibroglandular breast. These results align well with the cylinder phantom Monte Carlo studies which also showed a marginal difference in dose delivered by a saddle trajectory in the

  3. [Clinical effect of three dimensional human body scanning system BurnCalc in the evaluation of burn wound area].

    Science.gov (United States)

    Lu, J; Wang, L; Zhang, Y C; Tang, H T; Xia, Z F

    2017-10-20

    Objective: To validate the clinical effect of three dimensional human body scanning system BurnCalc developed by our research team in the evaluation of burn wound area. Methods: A total of 48 burn patients treated in the outpatient department of our unit from January to June 2015, conforming to the study criteria, were enrolled in. For the first 12 patients, one wound on the limbs or torso was selected from each patient. The stability of the system was tested by 3 attending physicians using three dimensional human body scanning system BurnCalc to measure the area of wounds individually. For the following 36 patients, one wound was selected from each patient, including 12 wounds on limbs, front torso, and side torso, respectively. The area of wounds was measured by the same attending physician using transparency tracing method, National Institutes of Health (NIH) Image J method, and three dimensional human body scanning system BurnCalc, respectively. The time for getting information of 36 wounds by three methods was recorded by stopwatch. The stability among the testers was evaluated by the intra-class correlation coefficient (ICC). Data were processed with randomized blocks analysis of variance and Bonferroni test. Results: (1) Wound area of patients measured by three physicians using three dimensional human body scanning system BurnCalc was (122±95), (121±95), and (123±96) cm(2,) respectively, and there was no statistically significant difference among them ( F =1.55, P >0.05). The ICC among 3 physicians was 0.999. (2) The wound area of limbs of patients measured by transparency tracing method, NIH Image J method, and three dimensional human body scanning system BurnCalc was (84±50), (76±46), and (84±49) cm(2,) respectively. There was no statistically significant difference in the wound area of limbs of patients measured by transparency tracing method and three dimensional human body scanning system BurnCalc ( P >0.05). The wound area of limbs of patients

  4. Preoperative cerebral aneurysm assessment by three-dimensional CT angiography. Feasibility of surgery without cerebral angiography

    International Nuclear Information System (INIS)

    Kashiwagi, Shiro; Yamashita, Katsuhiro; Kato, Shoichi; Ito, Haruhide; Kurokawa, Kensuke; Watanabe, Yutaka

    1999-01-01

    The purpose of this study is to assess the capability of three-dimensional CT angiography (3D-CTA) to replace conventional catheter angiography as a preoperative examination for unruptured intracranial aneurysms. A prospective study was designed to evaluate 18 patients with 20 unruptured intracranial aneurysms (13 middle cerebral artery aneurysms, 6 anterior communicating artery aneurysms, and 1 internal carotid posterior communicating artery aneurysm) who underwent surgery. There were 12 women and 6 men with the average age of 63 years old. All patients were initially diagnosed as having intracranial aneurysms by MR angiography, followed by 3D-CTA and conventional catheter angiography for confirmation. Three experienced neurosurgeons were in charge of the operations. One of the neurosurgeons (surgeon 1) was provided with only 3D-CTA as the preoperative radiological evaluation, while the others (surgeon 2 and 3) were given through assessments with MRA, 3D-CTA, and conventional angiography. Surgeon 1 carried out the operations under careful observation by the surgeons 2 and 3. Problems encountered by the surgeon 1 during surgery were recorded. Neck clipping in 19 aneurysms and dome wrapping in 1 were successfully accomplished. All patients were discharged without complication. Surgeries went smoothly in 16 aneurysms with 3D-CTA alone. Discrepancies between the 3D-CTA findings and microsurgical anatomy were noted in 4 aneurysms: the size of the neck was overestimated in 3 aneurysms, the relationships to parent arteries were obscure in 2 aneurysms, and a perforating artery problematic to neck clipping was missed in 1 aneurysms by 3D-CTA. The results of this study support the notion that 3D-CTA can replace conventional catheter angiography as preoperative examination in the majority of regular-sized anterior circulation aneurysms. Nevertheless, surgeons should recognize and be prepared for the fact that 3D-CTA can give false impression about the aneurysm neck and

  5. Three dimensional CT angiography (3D-CTA) in ruptured aneurysm surgery on acute stage

    International Nuclear Information System (INIS)

    Matsumoto, Masato; Endo, Yuji; Nakano, Masayuki

    1998-01-01

    We evaluated three-dimensional CT angiography (3D-CTA) for the treatment of acutely ruptured cerebral aneurysms. Sixty patients with subarachnoid hemorrhage from cerebral aneurysms were investigated both by 3D-CTA and conventional angiography and 26 patients were studied using 3D-CTA without conventional angiography. In the 60 cases, both 3D-CTA and the conventional angiography revealed 100% accuracy in diagnosing ruptured aneurysms, and 3D-CTA and the conventional angiography showed 96% and 92% accuracy for unruptured aneurysms respectively. 3D-CTA was equal or superior to the conventional angiography. Based on these data, since December, 1996, we have operated on 26 consecutive patients with ruptured aneurysms located in the anterior circulation of the circle of Willis, using 3D-CTA without conventional angiography. Thirty-one aneurysms, including 5 associated unruptured aneurysms, were visualized by 3D-CTA and verified at surgery. All aneurysms were clipped successfully. We think that it will be possible to operate on most ruptured aneurysms using only 3D-CTA without the conventional angiography except for the cases of the following situations: if a cerebral infarction is present, conventional angiography is required to evaluate for a stenotic or occlusive lesion of the intracranial arteries, cervical carotid, or vertebral arteries; in cases of giant or large aneurysms, the dynamic information provided by the conventional angiography is needed in case bypass surgery is necessary; and for aneurysms close to bony structures, such as an internal carotid-ophthalmic artery aneurysm, conventional angiography is necessary. (author)

  6. Propagation of aortic dissection and visceral artery compromise. Three-dimensional analysis on CT angiography

    International Nuclear Information System (INIS)

    Minamiguchi, Hiroki

    2003-01-01

    artery were significant factors to explain the difference. Three-dimensional analysis using CT angiography was essential to understand the propagation of aortic dissection and visceral artery compromise. (author)

  7. Three-dimensional anisotropic adaptive filtering of projection data for noise reduction in cone beam CT

    Energy Technology Data Exchange (ETDEWEB)

    Maier, Andreas; Wigstroem, Lars; Hofmann, Hannes G.; Hornegger, Joachim; Zhu Lei; Strobel, Norbert; Fahrig, Rebecca [Department of Radiology, Stanford University, Stanford, California 94305 (United States); Department of Radiology, Stanford University, Stanford, California 94305 (United States) and Center for Medical Image Science and Visualization, Linkoeping University, Linkoeping (Sweden); Pattern Recognition Laboratory, Department of Computer Science, Friedrich-Alexander University of Erlangen-Nuremberg, 91054, Erlangen (Germany); Nuclear and Radiological Engineering and Medical Physics Programs, George W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332 (United States); Siemens AG Healthcare, Forchheim 91301 (Germany); Department of Radiology, Stanford University, Stanford, California 94305 (United States)

    2011-11-15

    Purpose: The combination of quickly rotating C-arm gantry with digital flat panel has enabled the acquisition of three-dimensional data (3D) in the interventional suite. However, image quality is still somewhat limited since the hardware has not been optimized for CT imaging. Adaptive anisotropic filtering has the ability to improve image quality by reducing the noise level and therewith the radiation dose without introducing noticeable blurring. By applying the filtering prior to 3D reconstruction, noise-induced streak artifacts are reduced as compared to processing in the image domain. Methods: 3D anisotropic adaptive filtering was used to process an ensemble of 2D x-ray views acquired along a circular trajectory around an object. After arranging the input data into a 3D space (2D projections + angle), the orientation of structures was estimated using a set of differently oriented filters. The resulting tensor representation of local orientation was utilized to control the anisotropic filtering. Low-pass filtering is applied only along structures to maintain high spatial frequency components perpendicular to these. The evaluation of the proposed algorithm includes numerical simulations, phantom experiments, and in-vivo data which were acquired using an AXIOM Artis dTA C-arm system (Siemens AG, Healthcare Sector, Forchheim, Germany). Spatial resolution and noise levels were compared with and without adaptive filtering. A human observer study was carried out to evaluate low-contrast detectability. Results: The adaptive anisotropic filtering algorithm was found to significantly improve low-contrast detectability by reducing the noise level by half (reduction of the standard deviation in certain areas from 74 to 30 HU). Virtually no degradation of high contrast spatial resolution was observed in the modulation transfer function (MTF) analysis. Although the algorithm is computationally intensive, hardware acceleration using Nvidia's CUDA Interface provided an 8

  8. Three-dimensional anisotropic adaptive filtering of projection data for noise reduction in cone beam CT

    International Nuclear Information System (INIS)

    Maier, Andreas; Wigstroem, Lars; Hofmann, Hannes G.; Hornegger, Joachim; Zhu Lei; Strobel, Norbert; Fahrig, Rebecca

    2011-01-01

    Purpose: The combination of quickly rotating C-arm gantry with digital flat panel has enabled the acquisition of three-dimensional data (3D) in the interventional suite. However, image quality is still somewhat limited since the hardware has not been optimized for CT imaging. Adaptive anisotropic filtering has the ability to improve image quality by reducing the noise level and therewith the radiation dose without introducing noticeable blurring. By applying the filtering prior to 3D reconstruction, noise-induced streak artifacts are reduced as compared to processing in the image domain. Methods: 3D anisotropic adaptive filtering was used to process an ensemble of 2D x-ray views acquired along a circular trajectory around an object. After arranging the input data into a 3D space (2D projections + angle), the orientation of structures was estimated using a set of differently oriented filters. The resulting tensor representation of local orientation was utilized to control the anisotropic filtering. Low-pass filtering is applied only along structures to maintain high spatial frequency components perpendicular to these. The evaluation of the proposed algorithm includes numerical simulations, phantom experiments, and in-vivo data which were acquired using an AXIOM Artis dTA C-arm system (Siemens AG, Healthcare Sector, Forchheim, Germany). Spatial resolution and noise levels were compared with and without adaptive filtering. A human observer study was carried out to evaluate low-contrast detectability. Results: The adaptive anisotropic filtering algorithm was found to significantly improve low-contrast detectability by reducing the noise level by half (reduction of the standard deviation in certain areas from 74 to 30 HU). Virtually no degradation of high contrast spatial resolution was observed in the modulation transfer function (MTF) analysis. Although the algorithm is computationally intensive, hardware acceleration using Nvidia's CUDA Interface provided an 8.9-fold

  9. Accuracy assessment of three-dimensional surface reconstructions of teeth from cone beam computed tomography scans

    NARCIS (Netherlands)

    Al-Rawi, B.; Hassan, B.; Vandenberge, B.; Jacobs, R.

    2010-01-01

    The use of three-dimensional (3D) models of the dentition obtained from cone beam computed tomography (CBCT) is becoming increasingly more popular in dentistry. A recent trend is to replace the traditional dental casts with digital CBCT models for diagnosis, treatment planning and simulation. The

  10. The usefulness of three-dimensional helical CT for the detection of abnormalities of the auditory ossicles

    International Nuclear Information System (INIS)

    Gong, Honghan; Hiraishi, Kumiko; Uesugi, Yasuo; Shimizu, Tadafumi; Narabayashi, Isamu

    1996-01-01

    To evaluate the usefulness of three-dimensional (3D) helical CT for the detection of abnormalities of the auditory ossicles, 3D helical CT of the middle ear was performed in seven patients with hearing disorder. It revealed that 4 patients had congenital deficiency of the auditory ossicles, 2 patients with chronic otitis media had shortening of the incus and one patient with head injury had doubtful fracture of the incus. This study indicated that 3D helical CT of the middle ear can represent the auditory ossicles objectively and can offer detailed diagnosis. (author)

  11. CT scans in encephalitis

    International Nuclear Information System (INIS)

    Imanishi, Masami; Morimoto, Tetsuya; Iida, Noriyuki; Hisanaga, Manabu; Kinugawa, Kazuhiko

    1980-01-01

    Generally, CT scans reveal a decrease in the volume of the ventricular system, sylvian fissures and cortical sulci in the acute stage of encephalitis, and softening of the cerebral lobes with dilatation of the lateral ventricles and subarachnoidian dilated spaces in the chronic stage. We encountered three cases of encephalitis: mumps (case 1), herpes simplex (case 2), and syphilis (case 3). In case 1, brain edema was seen in the acute stage and brain atrophy in the chronic stage. In case 2, necrosis of the temporal pole, which is pathognomonic in herpes simplex encephalitis, was recognized. And in case 3, multiple lesions whose CT appearance was enhanced by contrast materials were found scattered over the whole brain. These lesions were diagnosed as inflammatory granuloma by histological examination. (author)

  12. Contrast agent comparison for three-dimensional micro-CT angiography: A cadaveric study.

    Science.gov (United States)

    Kingston, Mitchell J; Perriman, Diana M; Neeman, Teresa; Smith, Paul N; Webb, Alexandra L

    2016-07-01

    Barium sulfate and lead oxide contrast media are frequently used for cadaver-based angiography studies. These contrast media have not previously been compared to determine which is optimal for the visualisation and measurement of blood vessels. In this study, the lower limb vessels of 16 embalmed Wistar rats, and four sets of cannulae of known diameter, were injected with one of three different contrast agents (barium sulfate and resin, barium sulfate and gelatin, and lead oxide combined with milk powder). All were then scanned using micro-computed tomography (CT) angiography and 3-D reconstructions generated. The number of branching generations of the rat lower limb vessels were counted and compared between the contrast agents using ANOVA. The diameter of the contrast-filled cannulae, were measured and used to calculate the accuracy of the measurements by comparing the bias and variance of the estimates. Intra- and inter-observer reliability were calculated using intra-class correlation coefficients. There was no significant difference (mean difference [MD] 0.05; MD 95% confidence interval [CI] -0.83 to 0.93) between the number of branching generations for barium sulfate-resin and lead oxide-milk powder. Barium sulfate-resin demonstrated less bias and less variance of the estimates (MD 0.03; standard deviation [SD] 1.96 mm) compared to lead oxide-milk powder (MD 0.11; SD 1.96 mm) for measurements of contrast-filled cannulae scanned at high resolution. Barium sulfate-resin proved to be more accurate than lead oxide-milk powder for high resolution micro-CT scans and is preferred due to its non-toxicity. This technique could be applied to any embalmed specimen model. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

  13. Primitive experience of three dimensional multi-slice spiral CT angiography for the follow-up of intracranial aneurysm clipping

    International Nuclear Information System (INIS)

    Yang Yunjun; Chen Weijian; Hu Zhangyong; Wu Enfu; Wang Meihao; Zhuge Qichuan; Zhongming; Cheng Jingliang; Ren Cuiping; Zhang Yong

    2008-01-01

    Objective To evaluate multi-slice three-dimensional CT angiography (MS 3D-CTA) for the follow-up of intracranial aneurysm clipping. Methods: MS 3D-CTA of 16 patients with intracranial aneurysm clipping were retrospectively analyzed. The patients were scanned on a 16-slice spiral CT (GE Lightspeed pro). Volume rendering(VR), thin maximum intensity projection(thin MIP) and multi-planar reconstruction (MPR) were employed in image postprocessing in all cases. Results: There were 17 clips in the 16 patients with aneurysm clipping. Six clips were located at the posterior communicating artery, 5 at the anterior communicating artery, 4 at the middle cerebral artery, and the remaining 2 clips were located at the pericallosal artery, in 1 patient. There were no abnormalities found in the aneurysm clipping region in 7 cases by MS 3D- CTA. There were residual aneurysm in 2 cases, parent artery stenosis in 4 cases, and artery spasm in 3 eases. There was no parent artery occlusion and clip displacement in all cases. VR showed excellent 3D spacial relations between the clip and parent artery in 12 cases, and showed good relations in 3 cases. The 1 case with 2 clips in the pericallosal artery showed heavy beam-hardening artifacts. The size and shape of aneurysm clips were clearly depicted by MPR and thin MIP, while 3D spacial relation of aneurysm clip and parent artery were poorly showed. Conclusion: MS 3D-CTA is a safe and efficient method for the follow-up of intracranialaneurysm clipping. Combined VR with MPR or thin MIP can well reveal postoperative changes after aneurysm clipping. (authors)

  14. Compact design of a transmission electron microscope-scanning tunneling microscope holder with three-dimensional coarse motion

    International Nuclear Information System (INIS)

    Svensson, K.; Jompol, Y.; Olin, H.; Olsson, E.

    2003-01-01

    A scanning tunneling microscope (STM) with a compact, three-dimensional, inertial slider design is presented. Inertial sliding of the STM tip, in three dimensions, enables coarse motion and scanning using only one piezoelectric tube. Using the same electronics both for scanning and inertial sliding, step lengths of less than 5% of the piezo range were achieved. The compact design, less than 1 cm3 in volume, ensures a low mechanical noise level and enables us to fit the STM into the sample holder of a transmission electron microscope (TEM), while maintaining atomic scale resolution in both STM and TEM imaging

  15. Computer-assisted three-dimensional reconstruction of the corticospinal system as a reference for CT and MRI

    Energy Technology Data Exchange (ETDEWEB)

    Buhmann, C. [Department of Neuroanatomy, Hannover Medical School (Germany)]|[University Hospital Eppendorf, Hamburg (Germany); Kretschmann, H.J. [Department of Neuroanatomy, Hannover Medical School (Germany)

    1998-09-01

    We present a three-dimensional (3D) anatomical computer-graphics model of the corticospinal system acquired from equidistant serial anatomical slices of six intracranially-fixed human brains. This model is part of a neuroanatomical reference system (NeuRef) which enables 3D visualization of the brain and shows the relationship of its components such as anatomical structures, functional fibre tracts and arteries. Sections through the models can be matched with corresponding CT or MR images. This allows the probable localisation of corticospinal fibres on CT or MRI. (orig.) (orig.) With 18 figs., 3 tabs., 40 refs.

  16. Computer-assisted three-dimensional reconstruction of the corticospinal system as a reference for CT and MRI

    International Nuclear Information System (INIS)

    Buhmann, C.; Kretschmann, H.J.

    1998-01-01

    We present a three-dimensional (3D) anatomical computer-graphics model of the corticospinal system acquired from equidistant serial anatomical slices of six intracranially-fixed human brains. This model is part of a neuroanatomical reference system (NeuRef) which enables 3D visualization of the brain and shows the relationship of its components such as anatomical structures, functional fibre tracts and arteries. Sections through the models can be matched with corresponding CT or MR images. This allows the probable localisation of corticospinal fibres on CT or MRI. (orig.) (orig.)

  17. Three-dimensional analysis of micro- and nanostructure of biomaterials and cells by method of scanning probe nanotomography

    Directory of Open Access Journals (Sweden)

    A. E. Efimov

    2017-01-01

    Full Text Available Aim: to perform a three-dimensional analysis of micro- and nanosctucture and quantitative morphological parameters of alginate spherical microcarriers and porous regenerated silk macrocarriers modifi ed by microparticles of decellularized rat liver matrix and human hepatoma HepG2 cells adhered to micro- and macro carriers. Materials and methods. Three-dimensional porous matrices made from regenerated silk by salt leaching technique and alginate spherical microcarriers fabricated by encapsulation were vitalized by human hepatome HepG2 cells. Study of three-dimensional structure of cells and micro- and macro carriers was carried out at –120 °С by scanning probe cryonanotomography technique with use of experimental setup combining cryoultramicrotome and scanning probe microscope.Results. Three-dimensional nanotomographical reconstructions of HepG2 cells adhered to macropore wall of regenerated silk macrocarrier and to spherical alginate microcarrier are obtained. Morphological parameters (mean roughness, effective surface area and autocorrelation length are determined for surfaces of macro and microcarriers and adhered cells. The determined mean roughness of alginate microcarrier surface is 76.4 ± 7.5 nm, while that of surface of macropore wall of regenerated silk macrocarrier is 133.8 ± 16.2 nm. At the same time mean roughness of cells adhered to micro- and macrocarriers are 118.5 ± 9.0 и 158.8 ± 21.6 nm correspondingly. Three-dimensional reconstructions of intracellular compartments with dimensions from 140 to 500 nm are also obtained.Conclusion. Obtained as a result of study quantitative morphology characteristics of surfaces of cell carriers and adhered cells show signifi cant degree of correlation of morphological parameters of cells and their carriers. Use of scanning probe cryonanotomography technique for three-dimensional analysis of structure and characteristics of biomaterials, cells and bio-artifi cial cellular systems

  18. Three-dimensional visualization and measurement of water distributions in PEFC by dynamic CT method on neutron radiography

    International Nuclear Information System (INIS)

    Hashimoto, Michinori; Murakawa, Hideki; Sugimoto, Katsumi; Asano, Hitoshi; Takenaka, Nobuyuki; Mochiki, Koh-ichi

    2011-01-01

    Visualization of dynamic three-dimensional water behavior in a PEFC stack was carried out by neutron CT for clarifying water effects on performances of a Polymer Electrolyte Fuel Cell (PEFC) stack. Neutron radiography system at JRR-3 in Japan Atomic Energy Agency was used. An operating stack with three cells based on Japan Automobile Research Institute standard was visualized. A consecutive CT reconstruction method by rotating the fuel stack continuously was developed by using a neutron image intensifier and a C-MOS high speed video camera. The dynamic water behavior in channels in the operating PEFC stack was clearly visualized 15 sec in interval by the developed dynamic neutron CT system. From the CT reconstructed images, evaluation of water amount in each cell was carried out. It was shown that the water distribution in each cell was correlated well with power generation characteristics in each cell. (author)

  19. Three-dimensional spiral CT during arterial portography: comparison of three rendering techniques.

    Science.gov (United States)

    Heath, D G; Soyer, P A; Kuszyk, B S; Bliss, D F; Calhoun, P S; Bluemke, D A; Choti, M A; Fishman, E K

    1995-07-01

    The three most common techniques for three-dimensional reconstruction are surface rendering, maximum-intensity projection (MIP), and volume rendering. Surface-rendering algorithms model objects as collections of geometric primitives that are displayed with surface shading. The MIP algorithm renders an image by selecting the voxel with the maximum intensity signal along a line extended from the viewer's eye through the data volume. Volume-rendering algorithms sum the weighted contributions of all voxels along the line. Each technique has advantages and shortcomings that must be considered during selection of one for a specific clinical problem and during interpretation of the resulting images. With surface rendering, sharp-edged, clear three-dimensional reconstruction can be completed on modest computer systems; however, overlapping structures cannot be visualized and artifacts are a problem. MIP is computationally a fast technique, but it does not allow depiction of overlapping structures, and its images are three-dimensionally ambiguous unless depth cues are provided. Both surface rendering and MIP use less than 10% of the image data. In contrast, volume rendering uses nearly all of the data, allows demonstration of overlapping structures, and engenders few artifacts, but it requires substantially more computer power than the other techniques.

  20. Three-dimensional C-arm CT-guided transjugular intrahepatic portosystemic shunt placement: Feasibility, technical success and procedural time

    Energy Technology Data Exchange (ETDEWEB)

    Ketelsen, Dominik; Groezinger, Gerd; Maurer, Michael; Grosse, Ulrich; Horger, Marius; Nikolaou, Konstantin; Syha, Roland [University of Tuebingen, Department of Diagnostic and Interventional Radiology, Tuebingen (Germany); Lauer, Ulrich M. [University of Tuebingen, Internal Medicine I, Department of Gastroenterology, Hepatology and Infectious disease, Tuebingen (Germany)

    2016-12-15

    Establishment of transjugular intrahepatic portosystemic shunts (TIPS) constitutes a standard procedure in patients suffering from portal hypertension. The most difficult step in TIPS placement is blind puncture of the portal vein. This study aimed to evaluate three-dimensional mapping of portal vein branches and targeted puncture of the portal vein. Twelve consecutive patients suffering from refractory ascites by liver cirrhosis were included in this retrospective study to evaluate feasibility, technical success and procedural time of C-arm CT-targeted puncture of the portal vein. As a control, 22 patients receiving TIPS placement with fluoroscopy-guided blind puncture were included to compare procedural time. Technical success could be obtained in 100 % of the study group (targeted puncture) and in 95.5 % of the control group (blind puncture). Appropriate, three-dimensional C-arm CT-guided mapping of the portal vein branches could be achieved in all patients. The median number of punctures in the C-arm CT-guided study group was 2 ± 1.3 punctures. Procedural time was significantly lower in the study group (14.8 ± 8.2 min) compared to the control group (32.6 ± 22.7 min) (p = 0.02). C-arm CT-guided portal vein mapping is technically feasible and a promising tool for TIPS placement resulting in a significant reduction of procedural time. (orig.)

  1. Comparison of prostate positioning guided by three-dimensional transperineal ultrasound and cone beam CT

    Energy Technology Data Exchange (ETDEWEB)

    Li, Minglun; Ballhausen, Hendrik; Hegemann, Nina-Sophie; Reiner, Michael; Manapov, Farkhad; Corradini, Stefanie; Ganswindt, Ute; Belka, Claus [University Hospital Munich, LMU Munich, Department of Radiation Oncology, Munich (Germany); Tritschler, Stefan; Gratzke, Christian [University Hospital Munich, LMU Munich, Department of Urology, Munich (Germany)

    2017-03-15

    The accuracy of a transperineal three-dimensional ultrasound system (3DUS) was assessed for prostate positioning and compared to fiducial- and bone-based positioning in kV cone beam computed tomography (CBCT) during definitive radiotherapy of prostate cancer. Each of the 7 patients had three fiducial markers implanted into the prostate before treatment. Prostate positioning was simultaneously measured by 3DUS and CBCT before each fraction. In total, 177 pairs of 3DUS and CBCT scans were collected. Bone-match and seed-match were performed for each CBCT. Using seed-match as a reference, the accuracy of 3DUS and bone-match was evaluated. Systematic and random errors as well as optimal setup margins were calculated for 3DUS and bone-match. The discrepancy between 3DUS and seed-match in CBCT (average ± standard deviation) was 0.0 ± 1.7 mm laterally, 0.2 ± 2.0 mm longitudinally, and 0.3 ± 1.7 mm vertically. Using seed-match as a reference, systematic errors for 3DUS were 1.2 mm, 1.1 mm, and 0.9 mm; and random errors were 1.4 mm, 1.8 mm, and 1.6 mm, on lateral, longitudinal, and vertical axes, respectively. By analogy, the difference of bone-match to seed-match was 0.1 ± 1.1 mm laterally, 1.3 ± 3.8 mm longitudinally, and 1.3 ± 4.5 mm vertically. Systematic errors were 0.5 mm, 2.2 mm, and 2.6 mm; and random errors were 1.0 mm, 3.1 mm, and 3.9 mm on lateral, longitudinal, and vertical axes, respectively. The accuracy of 3DUS was significantly higher than that of bone-match on longitudinal and vertical axes, but not on the lateral axis. Image-guided radiotherapy of prostate cancer based on transperineal 3DUS was feasible, with overall small discrepancy to seed-match in CBCT in this retrospective study. Compared to bone-match, transperineal 3DUS achieved higher accuracy on longitudinal and vertical axes. (orig.) [German] Bewertung der Genauigkeit eines transperinealen dreidimensionalen Ultraschallsystems (3DUS) fuer die Prostatapositionierung und Vergleich mit

  2. Three-dimensional apoptotic nuclear behavior analyzed by means of Field Emission in Lens Scanning Electron Microscope

    Directory of Open Access Journals (Sweden)

    S. Salucci

    2015-09-01

    Full Text Available Apoptosis is an essential biological function required during embryogenesis, tissue homeostasis, organ development and immune system regulation. It is an active cell death pathway involved in a variety of pathological conditions. During this process cytoskeletal proteins appear damaged and undergo an enzymatic disassembling, leading to formation of apoptotic features. This study was designed to examine the three-dimensional chromatin behavior and cytoskeleton involvement, in particular actin re-modeling. HL-60 cells, exposed to hyperthermia, a known apoptotic trigger, were examined by means of a Field Emission in Lens Scanning Electron Microscope (FEISEM. Ultrastructural observations revealed in treated cells the presence of apoptotic patterns after hyperthermia trigger. In particular, three-dimensional apoptotic chromatin rearrangements appeared involving the translocation of filamentous actin from cytoplasm to the nucleus. FEISEM immunogold techniques showed actin labeling and its precise three-dimensional localization in the diffuse chromatin, well separated from the condensed one. The actin presence in dispersed chromatin inside the apoptotic nucleus can be considered an important feature, indispensable to permit the apoptotic machinery evolution.

  3. Three-dimensional ultrastructure of osteocytes assessed by focused ion beam-scanning electron microscopy (FIB-SEM).

    Science.gov (United States)

    Hasegawa, Tomoka; Yamamoto, Tomomaya; Hongo, Hiromi; Qiu, Zixuan; Abe, Miki; Kanesaki, Takuma; Tanaka, Kawori; Endo, Takashi; de Freitas, Paulo Henrique Luiz; Li, Minqi; Amizuka, Norio

    2018-04-01

    The aim of this study is to demonstrate the application of focused ion beam-scanning electron microscopy, FIB-SEM for revealing the three-dimensional features of osteocytic cytoplasmic processes in metaphyseal (immature) and diaphyseal (mature) trabeculae. Tibiae of eight-week-old male mice were fixed with aldehyde solution, and treated with block staining prior to FIB-SEM observation. While two-dimensional backscattered SEM images showed osteocytes' cytoplasmic processes in a fragmented fashion, three-dimensional reconstructions of FIB-SEM images demonstrated that osteocytes in primary metaphyseal trabeculae extended their cytoplasmic processes randomly, thus maintaining contact with neighboring osteocytes and osteoblasts. In contrast, diaphyseal osteocytes extended thin cytoplasmic processes from their cell bodies, which ran perpendicular to the bone surface. In addition, these osteocytes featured thick processes that branched into thinner, transverse cytoplasmic processes; at some point, however, these transverse processes bend at a right angle to run perpendicular to the bone surface. Osteoblasts also possessed thicker cytoplasmic processes that branched off as thinner processes, which then connected with cytoplasmic processes of neighboring osteocytes. Thus, FIB-SEM is a useful technology for visualizing the three-dimensional structures of osteocytes and their cytoplasmic processes.

  4. Production of accurate skeletal models of domestic animals using three-dimensional scanning and printing technology.

    Science.gov (United States)

    Li, Fangzheng; Liu, Chunying; Song, Xuexiong; Huan, Yanjun; Gao, Shansong; Jiang, Zhongling

    2018-01-01

    Access to adequate anatomical specimens can be an important aspect in learning the anatomy of domestic animals. In this study, the authors utilized a structured light scanner and fused deposition modeling (FDM) printer to produce highly accurate animal skeletal models. First, various components of the bovine skeleton, including the femur, the fifth rib, and the sixth cervical (C6) vertebra were used to produce digital models. These were then used to produce 1:1 scale physical models with the FDM printer. The anatomical features of the digital models and three-dimensional (3D) printed models were then compared with those of the original skeletal specimens. The results of this study demonstrated that both digital and physical scale models of animal skeletal components could be rapidly produced using 3D printing technology. In terms of accuracy between models and original specimens, the standard deviations of the femur and the fifth rib measurements were 0.0351 and 0.0572, respectively. All of the features except the nutrient foramina on the original bone specimens could be identified in the digital and 3D printed models. Moreover, the 3D printed models could serve as a viable alternative to original bone specimens when used in anatomy education, as determined from student surveys. This study demonstrated an important example of reproducing bone models to be used in anatomy education and veterinary clinical training. Anat Sci Educ 11: 73-80. © 2017 American Association of Anatomists. © 2017 American Association of Anatomists.

  5. Prenatal diagnosis of chondrodysplasia punctata tibia-metacarpal type using multidetector CT and three-dimensional reconstruction

    Energy Technology Data Exchange (ETDEWEB)

    Miyazaki, Osamu [National Centre for Child Health and Development, Department of Radiology, Tokyo (Japan); Nishimura, Gen [Tokyo Metropolitan Kiyose Children' s Hospital, Department of Radiology, Tokyo (Japan); Sago, Haruhiko; Watanabe, Noriyoshi; Ebina, Shunsuke [National Centre for Child Health and Development, Department of Perinatal Medicine and Maternal Care, Tokyo (Japan)

    2007-11-15

    We report a case of chondrodysplasia punctata tibia-metacarpal type (CDP-TM) that was diagnosed prenatally using multidetector CT (MDCT) with three-dimensional (3-D) CT reconstructions. Prenatal US had shown severe thoracic hypoplasia and rhizomelic shortening of the limbs, raising the suspicion of thanatophoric dysplasia. However, MDCT showed punctate calcifications in the epiphyseal cartilage of the humeri and femora, carpal bones, and paravertebral region. On 3-D CT, the tibiae were much shorter than the fibulae, the humeri were very short and bowed, and severe platyspondyly was evident. These findings led to the diagnosis of CDP-TM. The diagnosis was confirmed on postnatal radiographs. Prenatal MDCT with 3-D images may make a useful contribution to prenatal diagnosis in selected fetuses with severe skeletal dysplasia. (orig.)

  6. Pre-operative evaluation of cleft palate using three dimensional computerized tomography (s-D CT)

    International Nuclear Information System (INIS)

    Azia, A.; Hashmi, R.

    1999-01-01

    Cleft palate is a congenital anomaly with major development concerns. Surgery with bone grafting is often required to correct the lesion. With the introduction of 3-D CT the evaluation of cleft pa late has become more accurate. We present two cases of cleft palate, which were operated upon with bone grafting. We employed 3-D CT techniques in addition to the conventional 2-D CT, 3-D CT improves the estimation of the required bone graft and signification reduces length of surgery and complications. (author)

  7. 4 T MRI of chondrocalcinosis in combination with three-dimensional CT, radiography, and arthroscopy: a report of three cases

    International Nuclear Information System (INIS)

    Suan, J.C.; Chhem, R.K.; Gati, J.S.; Norley, C.J.; Holdsworth, D.W.

    2005-01-01

    To describe 4 T MRI techniques in imaging chondrocalcinosis within the knee and examine the results together with those demonstrated using three-dimensional (3D) computed tomography, conventional radiography, and arthroscopy. From a larger clinical imaging study of early osteoarthritis, knee arthroscopy patients were imaged using high-field MRI and high-resolution 3D CT prior to their surgery. Retrospective review of the imaging data diagnosed three patients with chondrocalcinosis. Fat-suppressed 3D spoiled gradient (3D SPGR) and two-dimensional fat-suppressed fast spin echo (FSE) imaging was performed at 4 T. The MR images, multi-planar reformatted CT (MPR-CT) and maximum intensity projection CT (MIP-CT) images, and radiographs were examined by a musculoskeletal radiologist for the presence and location of chondrocalcinosis. The findings from arthroscopy were also included. MRI showed 16 sites of punctate hypointense regions from 18 articular surfaces and five of six menisci with similar signal characteristics. Both meniscal chondrocalcinosis and meniscal tears were clearly visible using the 3D SPGR sequence. Only three sites were demonstrated to have calcification using MPR-CT and MIP-CT revealed an additional three. In articular cartilage surfaces showing surface disruption, arthroscopy demonstrated 11 sites with crystal deposition. Arthroscopy also revealed five menisci with calcification present. Our preliminary findings suggest that imaging chondrocalcinosis using spoiled gradient 4 T MRI is superior and complementary to the other imaging modalities in the detection of crystal deposition in both articular cartilage and menisci. (orig.)

  8. 4 T MRI of chondrocalcinosis in combination with three-dimensional CT, radiography, and arthroscopy: a report of three cases

    Energy Technology Data Exchange (ETDEWEB)

    Suan, J.C.; Chhem, R.K.; Gati, J.S.; Norley, C.J.; Holdsworth, D.W. [Robarts Research Institute, Imaging Research Laboratories, London, Ontario (Canada)

    2005-11-01

    To describe 4 T MRI techniques in imaging chondrocalcinosis within the knee and examine the results together with those demonstrated using three-dimensional (3D) computed tomography, conventional radiography, and arthroscopy. From a larger clinical imaging study of early osteoarthritis, knee arthroscopy patients were imaged using high-field MRI and high-resolution 3D CT prior to their surgery. Retrospective review of the imaging data diagnosed three patients with chondrocalcinosis. Fat-suppressed 3D spoiled gradient (3D SPGR) and two-dimensional fat-suppressed fast spin echo (FSE) imaging was performed at 4 T. The MR images, multi-planar reformatted CT (MPR-CT) and maximum intensity projection CT (MIP-CT) images, and radiographs were examined by a musculoskeletal radiologist for the presence and location of chondrocalcinosis. The findings from arthroscopy were also included. MRI showed 16 sites of punctate hypointense regions from 18 articular surfaces and five of six menisci with similar signal characteristics. Both meniscal chondrocalcinosis and meniscal tears were clearly visible using the 3D SPGR sequence. Only three sites were demonstrated to have calcification using MPR-CT and MIP-CT revealed an additional three. In articular cartilage surfaces showing surface disruption, arthroscopy demonstrated 11 sites with crystal deposition. Arthroscopy also revealed five menisci with calcification present. Our preliminary findings suggest that imaging chondrocalcinosis using spoiled gradient 4 T MRI is superior and complementary to the other imaging modalities in the detection of crystal deposition in both articular cartilage and menisci. (orig.)

  9. Three-dimensional analysis of mesiobuccal root canal of Japanese maxillary first molar using Micro-CT

    International Nuclear Information System (INIS)

    Yamada, Masashi; Ide, Yoshinobu; Matsunaga, Satoru; Kato, Hiroshi; Nakagawa, Kan-Ichi

    2011-01-01

    The objective of this study was to three-dimensionally observe the morphological characteristics of mesiobuccal root canals of Japanese maxillary first molars using microcomputed tomography (Micro-CT) and classify root canal variations. This study used 90 maxillary first molars. Three-dimensional reconstruction was performed using data obtained by Micro-CT, and cross-sections of the root canals were observed. Moreover, the root canal morphology was classified by the configuration and root canal diameter, and was evaluated for occurrence using the classification by Weine et al. (1969) as a reference. Overall, single root canals were observed in 44.4%, incomplete separation root canals in 22.3%, and completely separate root canals (upper and lower separation root canals) in 33.3%. Mesiobuccal root canals often had intricate configurations, and accessory root canals (lateral canals and apical ramifications) were observed in most of the mesiobuccal root canals (76.7%), irrespective of whether there were ramifications of the main root canals. While there were no marked differences in the incidence of root canal ramifications between this study and earlier reports, the incidence of accessory root canals was higher in this study. This result may be explained by the far more superior visualization ability of Micro-CT than conventional methods, which allowed the detection of microscopic apical ramifications previously difficult to observe. (author)

  10. MR vs CT imaging: low rectal cancer tumour delineation for three-dimensional conformal radiotherapy.

    LENUS (Irish Health Repository)

    O'Neill, B D P

    2009-06-01

    Modern three-dimentional radiotherapy is based upon CT. For rectal cancer, this relies upon target definition on CT, which is not the optimal imaging modality. The major limitation of CT is its low inherent contrast resolution. Targets defined by MRI could facilitate smaller, more accurate, tumour volumes than CT. Our study reviewed imaging and planning data for 10 patients with locally advanced low rectal cancer (defined as < 6 cm from the anal verge on digital examination). Tumour volume and location were compared for sagittal pre-treatment MRI and planning CT. CT consistently overestimated all tumour radiological parameters. Estimates of tumour volume, tumour length and height of proximal tumour from the anal verge were larger on planning CT than on MRI (p < 0.05). Tumour volumes defined on MRI are smaller, shorter and more distal from the anal sphincter than CT-based volumes. For radiotherapy planning, this may result in smaller treatment volumes, which could lead to a reduction in dose to organs at risk and facilitate dose escalation.

  11. Helical CT for emergency patients with cerebrovascular diseases. Diagnosis of cerebral aneurysms with subarachnoid hemorrhage (SAH) by three-dimensional CT angiography (3D-CTA)

    International Nuclear Information System (INIS)

    Matsumoto, Masato; Satoh, Naoki; Kobayashi, Touru; Kodama, Namio; Nakano, Masayuki; Watanabe, Youichi; Fujii, Masayuki

    1996-01-01

    Recently, the usefulness of three-dimensional CT angiography (3D-CTA) using helical CT has been reported. Although 3D-CTA has been applied for neurosurgical diseases, especially for surgical planning, it has not done for emergency patients because of the long time required for image reconstruction and location of a helical CT scanner. We studied emergency patients with SAH, and compared the 3D-CTA with angiography and surgical findings, using TOSHIBA X vigor. Twenty-two patients with SAH were evaluated. The helical CT was performed for 55 seconds with a bolus injection of 90 ml non-ionic, iodinated contrast medium at a rate of 3 ml/sec with a delay of 20 sec. Angiography was carried out immediately after the helical CT. Eighteen of 22 cases were operated on urgently. We were able to create the 3D-CTA in about 7 minutes, and diagnose aneurysms by the 3D-CTA before angiography. The 3D-CTA was able to demonstrate 30 of 31 aneurysms including 9 unruptured aneurysms. An unruptured internal carotid-posterior communicating artery aneurysm 1.3 mm in diameter and associated with a ruptured aneurysm was not detected by either the 3D-CTA or angiography. On the other hand, an unruptured Acom aneurysm 0.8 mm in diameter and associated with a ruptured aneurysm could be detected by the: 3D-CTA, but not by angiography. The 3D-CTA gave us useful information concerning the anatomical relationship of the aneurysm, its neck and parent artery, and the surrounding branches. There were no complications or side effects associated with the helical CT scan. Although the 3D-CTA requires further development of visualization of small arteries less than 1 mm in diameter, such as perforating arteries, subtraction technique of bony structure, and a method for checking cervical arteries, it is useful for diagnosis of emergency patients with SAH and urgent operations. We believe that an operation might be performed by only the 3D-CTA without the angiography in the near future. (author)

  12. Helical CT for emergency patients with cerebrovascular diseases. Diagnosis of cerebral aneurysms with subarachnoid hemorrhage (SAH) by three-dimensional CT angiography (3D-CTA)

    Energy Technology Data Exchange (ETDEWEB)

    Matsumoto, Masato; Satoh, Naoki; Kobayashi, Touru; Kodama, Namio; Nakano, Masayuki; Watanabe, Youichi; Fujii, Masayuki [Fukushima Medical School (Japan)

    1996-05-01

    Recently, the usefulness of three-dimensional CT angiography (3D-CTA) using helical CT has been reported. Although 3D-CTA has been applied for neurosurgical diseases, especially for surgical planning, it has not done for emergency patients because of the long time required for image reconstruction and location of a helical CT scanner. We studied emergency patients with SAH, and compared the 3D-CTA with angiography and surgical findings, using TOSHIBA X vigor. Twenty-two patients with SAH were evaluated. The helical CT was performed for 55 seconds with a bolus injection of 90 ml non-ionic, iodinated contrast medium at a rate of 3 ml/sec with a delay of 20 sec. Angiography was carried out immediately after the helical CT. Eighteen of 22 cases were operated on urgently. We were able to create the 3D-CTA in about 7 minutes, and diagnose aneurysms by the 3D-CTA before angiography. The 3D-CTA was able to demonstrate 30 of 31 aneurysms including 9 unruptured aneurysms. An unruptured internal carotid-posterior communicating artery aneurysm 1.3 mm in diameter and associated with a ruptured aneurysm was not detected by either the 3D-CTA or angiography. On the other hand, an unruptured Acom aneurysm 0.8 mm in diameter and associated with a ruptured aneurysm could be detected by the: 3D-CTA, but not by angiography. The 3D-CTA gave us useful information concerning the anatomical relationship of the aneurysm, its neck and parent artery, and the surrounding branches. There were no complications or side effects associated with the helical CT scan. Although the 3D-CTA requires further development of visualization of small arteries less than 1 mm in diameter, such as perforating arteries, subtraction technique of bony structure, and a method for checking cervical arteries, it is useful for diagnosis of emergency patients with SAH and urgent operations. We believe that an operation might be performed by only the 3D-CTA without the angiography in the near future. (author)

  13. 16 multi-slice CT three-dimensional and multiplanar reconstruction for evaluation of pediatric congenital scoliosis

    International Nuclear Information System (INIS)

    Peng Yun; Zhang Ningning; Zhang Xuejun; Sun Guoqiang; Zeng Jinjin

    2006-01-01

    Objective: Our study is to use of 16 MSCT three-dimensional images and multiplanar reconstruction images in the preoperative investigation of patients with congenital scoliosis, to study its technical advantage and work out surgical plan. Methods: Twenty-seven pediatric patients with congenital scoliosis processing between April to October 2004 were reviewed, including 13 boys and 14 girls. X-ray plain film and sixteen multi-slice CT examination on curved/standard multiplanar reconstruction and three- dimensional computed tomographic imaging may offer, many potential advantages for defining congenital spine anomalies liable to cause progression of scoliosis, including visualization of the deformity in any plane, from any angle, with the overlying structures subtracted. Results: Ten patients had segmentation defects, 6 patients underwent formation defects, 11 patients had complex, unclassifiable anomalies. The patients of rib deformity were found in 15 patients, the most prominent part of the rib cage deformity was at the same level as the most rotated vertebra in 7 patients; 8 patients had vertebral anomalies accompanied with diastematomyelie, including 6 patients with uncompleted or completed bony spur. In 19 of 27 cases, the muhiplanar reconstruction and three-dimensional images allowed identification of unrecognized malformations and completely evaluated the degree of scoliosis, during conventional X-ray images and axial CT images, including volume 3D imaging evaluated approximately classification and modality of complex anomalies in 11 cases, which were unclassifiable malformation in 7 cases and unsegmented bar with contralateral hemivertebrae; 4 children had segmentation defects revealed unilateral unsegmented bar (3 cases) and bilateral block vertebra (1 case) in volume 3D reconstruction images; 2 children were found occultation hemivertebrae which were not been discovered during conventional X-ray images and axial CT images; and 2 children were revaluated

  14. Three-Dimensional Laser Scanning for Geometry Documentation and Construction Management of Highway Tunnels during Excavation

    Science.gov (United States)

    Gikas, Vassilis

    2012-01-01

    Driven by progress in sensor technology, computer software and data processing capabilities, terrestrial laser scanning has recently proved a revolutionary technique for high accuracy, 3D mapping and documentation of physical scenarios and man-made structures. Particularly, this is of great importance in the underground space and tunnel construction environment as surveying engineering operations have a great impact on both technical and economic aspects of a project. This paper discusses the use and explores the potential of laser scanning technology to accurately track excavation and construction activities of highway tunnels. It provides a detailed overview of the static laser scanning method, its principles of operation and applications for tunnel construction operations. Also, it discusses the planning, execution, data processing and analysis phases of laser scanning activities, with emphasis given on geo-referencing, mesh model generation and cross-section extraction. Specific case studies are considered based on two construction sites in Greece. Particularly, the potential of the method is examined for checking the tunnel profile, producing volume computations and validating the smoothness/thickness of shotcrete layers at an excavation stage and during the completion of excavation support and primary lining. An additional example of the use of the method in the geometric documentation of the concrete lining formwork is examined and comparisons against dimensional tolerances are examined. Experimental comparisons and analyses of the laser scanning method against conventional surveying techniques are also considered. PMID:23112655

  15. Method and apparatus for a high-resolution three dimensional confocal scanning transmission electron microscope

    Science.gov (United States)

    de Jonge, Niels [Oak Ridge, TN

    2010-08-17

    A confocal scanning transmission electron microscope which includes an electron illumination device providing an incident electron beam propagating in a direction defining a propagation axis, and a precision specimen scanning stage positioned along the propagation axis and movable in at least one direction transverse to the propagation axis. The precision specimen scanning stage is configured for positioning a specimen relative to the incident electron beam. A projector lens receives a transmitted electron beam transmitted through at least part of the specimen and focuses this transmitted beam onto an image plane, where the transmitted beam results from the specimen being illuminated by the incident electron beam. A detection system is placed approximately in the image plane.

  16. Newly defined landmarks for a three-dimensionally based cephalometric analysis: a retrospective cone-beam computed tomography scan review.

    Science.gov (United States)

    Lee, Moonyoung; Kanavakis, Georgios; Miner, R Matthew

    2015-01-01

    To identify two novel three-dimensional (3D) cephalometric landmarks and create a novel three-dimensionally based anteroposterior skeletal measurement that can be compared with traditional two-dimensional (2D) cephalometric measurements in patients with Class I and Class II skeletal patterns. Full head cone-beam computed tomography (CBCT) scans of 100 patients with all first molars in occlusion were obtained from a private practice. InvivoDental 3D (version 5.1.6, Anatomage, San Jose, Calif) was used to analyze the CBCT scans in the sagittal and axial planes to create new landmarks and a linear 3D analysis (M measurement) based on maxillary and mandibular centroids. Independent samples t-test was used to compare the mean M measurement to traditional 2D cephalometric measurements, ANB and APDI. Interexaminer and intraexaminer reliability were evaluated using 2D and 3D scatterplots. The M measurement, ANB, and APDI could statistically differentiate between patients with Class I and Class II skeletal patterns (P < .001). The M measurement exhibited a correlation coefficient (r) of -0.79 and 0.88 with APDI and ANB, respectively. The overall centroid landmarks and the M measurement combine 2D and 3D methods of imaging; the measurement itself can distinguish between patients with Class I and Class II skeletal patterns and can serve as a potential substitute for ANB and APDI. The new three-dimensionally based landmarks and measurements are reliable, and there is great potential for future use of 3D analyses for diagnosis and research.

  17. Performance analysis of three-dimensional ridge acquisition from live finger and palm surface scans

    Science.gov (United States)

    Fatehpuria, Abhishika; Lau, Daniel L.; Yalla, Veeraganesh; Hassebrook, Laurence G.

    2007-04-01

    Fingerprints are one of the most commonly used and relied-upon biometric technology. But often the captured fingerprint image is far from ideal due to imperfect acquisition techniques that can be slow and cumbersome to use without providing complete fingerprint information. Most of the diffculties arise due to the contact of the fingerprint surface with the sensor platen. To overcome these diffculties we have been developing a noncontact scanning system for acquiring a 3-D scan of a finger with suffciently high resolution which is then converted into a 2-D rolled equivalent image. In this paper, we describe certain quantitative measures evaluating scanner performance. Specifically, we use some image software components developed by the National Institute of Standards and Technology, to derive our performance metrics. Out of the eleven identified metrics, three were found to be most suitable for evaluating scanner performance. A comparison is also made between 2D fingerprint images obtained by the traditional means and the 2D images obtained after unrolling the 3D scans and the quality of the acquired scans is quantified using the metrics.

  18. Three-dimensional body scanning system for apparel mass-customization

    Science.gov (United States)

    Xu, Bugao; Huang, Yaxiong; Yu, Weiping; Chen, Tong

    2002-07-01

    Mass customization is a new manufacturing trend in which mass-market products (e.g., apparel) are quickly modified one at a time based on customers' needs. It is an effective competing strategy for maximizing customers' satisfaction and minimizing inventory costs. An automatic body measurement system is essential for apparel mass customization. This paper introduces the development of a body scanning system, body size extraction methods, and body modeling algorithms. The scanning system utilizes the multiline triangulation technique to rapidly acquire surface data on a body, and provides accurate body measurements, many of which are not available with conventional methods. Cubic B-spline curves are used to connect and smooth body curves. From the scanned data, a body form can be constructed using linear Coons surfaces. The body form can be used as a digital model of the body for 3-D garment design and for virtual try-on of a designed garment. This scanning system and its application software enable apparel manufacturers to provide custom design services to consumers seeking personal-fit garments.

  19. Accurate three dimensional characterization of ultrasonic sound fields (by computer controlled rotational scanning)

    International Nuclear Information System (INIS)

    Gundtoft, H.E.; Nielsen, T.

    1981-07-01

    A rotational scanning system has recently been developed at Risoe National Laboratory. It allows sound fields from ultrasonic transducers to be examined in 3 dimensions. Using different calculation and plotting programs, any section in the sound field can be plotted. Results from examination of transducers for automatic inspection are presented. (author)

  20. Analysis of the sacrum: CT with two-dimensional and three-dimensional imaging

    International Nuclear Information System (INIS)

    Magid, D.; Fishman, E.K.; Scott, W.W. Jr.; Brooker, A.F. Jr.

    1987-01-01

    Fifteen patients with sacral lesions were assessed using CT and volumetric 3D image rendering. Lesions imaged included sacral fractures, tumors, osteomyelitis, dysplasia, and sacroiliac diastasis. In all cases, transaxial CT alone was superior to conventional radiographs, and CT with 3D was more clinically useful than CT alone. The 3D real-time video format allows rotation and manipulation in several planes, including the X (spinal) and Z (somersaulting) axes, for optimal visualization of abnormalities. The Z axis gives unique unimpeded inlet, outlet, and ''bird's-eye'' views of the pelvis and sacrum, enhancing detection and characterization of sacral of SI disruptions and subsequent pelvic ring compromise. Because of the ease of assimilating information in such a format, 3D may become the key modality for preoperative planning and for postoperative follow-up

  1. Spinal CT scan, 2

    International Nuclear Information System (INIS)

    Nakagawa, Hiroshi

    1982-01-01

    Plain CT described fairly accurately the anatomy and lesions of the lumbar and sacral spines on their transverse sections. Since hernia of the intervertebral disc could be directly diagnosed by CT, indications of myelography could be restricted. Spinal-canal stenosis of the lumbar spine occurs because of various factors, and CT not only demonstrated the accurate size and morphology of bony canals, but also elucidated thickening of the joints and yellow ligament. CT was also useful for the diagnosis of tumors in the lumbar and sacral spines, visualizing the images of bone changes and soft tissues on the trasverse sections. But the diagnosis of intradural tumors required myelography and metrizamide CT. CT has become important for the diagnosis of spinal and spinal-cord diseases and for selection of the route of surgical arrival. (Chiba, N.)

  2. A three-dimensional CT-based target definition for elective irradiation of the neck

    International Nuclear Information System (INIS)

    Nowak, Peter J.C.M.; Wijers, Oda B.; Lagerwaard, Frank J.; Levendag, Peter C.

    1999-01-01

    Introduction: Elective treatment of the clinically node-negative neck by radiation results in excellent control rates. However, radiation therapy with its organ-preserving properties is not without morbidity. Side effects of elective neck irradiation are mainly due to damage of the major and minor salivary glands, resulting in the dry mouth syndrome. Given that RT is the preferred treatment modality in case of elective treatment of the neck in many institutions, it is of utmost importance to try and reduce the associated sequelae of RT. Material and Methods: With the introduction of CT-planning systems and the development of 3D conformal radiation therapy (3D CRT) techniques, it has become feasible to deliver adequate doses of radiation to the target (neck) and at the same time saving (parts of) the salivary glands from doses beyond tolerance. A prerequisite for these techniques is that they require a precise knowledge of the target (i.e., of the elective neck) on CT. To be able to correlate borders of the surgical levels in the neck (I-VI) with structures seen on CT, an anatomical study, using two fixed (phenol, formaldehyde) human cadavers, was performed. Subsequently, the 6 potential lymph node regions in the neck on CT were defined. Results and Discussion: The reference for the current 3D CT-based definition of the lymph node regions in the neck is the official report of the American Academy of Otolaryngology, describing, based on surgical anatomy, the lymph node groups in the neck by Levels I-VI. The present investigation depicts reproducible landmarks on transversal CT images, corresponding to anatomical reference structures known from surgical levels (I-VI) and, this way, CT-based lymph node regions (1-6) were constructed

  3. The helical three-dimensional CT in the diagnosis of torticollis with occipitocondylar hypoplasia

    International Nuclear Information System (INIS)

    Ilkko, E.; Tikkakoski, T.; Pyhtinen, J.

    1998-01-01

    Congenital anomalies of the atlanto-occipital and atlantoaxial joints are rare. Those most commonly reported are atlantoaxial instability, basilar impression, anomalies of the odontoid process, laxity of the transverse atlantal ligament and atlanto-occipital fusion. Occipital condylar hypoplasia is infrequent and difficult to recognise. We recently diagnosed it using helical 3D CT in association with torticollis in two patients. The first patient had a several year history of torticollis. The second patient had acute cervical lymphadenitis associated with post-operative torticollis. 3D CT distinctly revealed atlantoaxial subluxation with hypoplasia of the occipital condyles in both cases. (Copyright (c) 1998 Elsevier Science B.V., Amsterdam. All rights reserved.)

  4. The helical three-dimensional CT in the diagnosis of torticollis with occipitocondylar hypoplasia

    International Nuclear Information System (INIS)

    Ilkko, E.; Tikkakoski, T.; Pyhtinen, J.

    1998-01-01

    Congenital anomalies of the atlanto-occipital and atlantoaxial joints are rare. Those most commonly reported are atlantoaxial instability, basilar impression, anomalies of the odontoid process, laxity of the transverse atlantal ligament and atlanto-occipital fusion. Occipital condylar hypoplasia is infrequent and difficult to recognise. We recently diagnosed it using helical 3D CT in association with torticollis in two patients. The first patient had a several year history of torticollis. The second patient had acute cervical lymphadenitis associated with post-operative torticollis. 3D CT distinctly revealed atlantoaxial subluxation with hypoplasia of the occipital condyles in both cases

  5. Real-time interactive three-dimensional display of CT and MR imaging volume data

    International Nuclear Information System (INIS)

    Yla-Jaaski, J.; Kubler, O.; Kikinis, R.

    1987-01-01

    Real-time reconstruction of surfaces from CT and MR imaging volume data is demonstrated using a new algorithm and implementation in a parallel computer system. The display algorithm accepts noncubic 16-bit voxels directly as input. Operations such as interpolation, classification by thresholding, depth coding, simple lighting effects, and removal of parts of the volume by clipping planes are all supported on-line. An eight-processor implementation of the algorithm renders surfaces from typical CT data sets in real time to allow interactive rotation of the volume

  6. Long term three dimensional tracking of orthodontic patients using registered cone beam CT and photogrammetry.

    Science.gov (United States)

    Boulanger, Pierre; Flores-Mir, Carlos; Ramirez, Juan F; Mesa, Elizabeth; Branch, John W

    2009-01-01

    The measurements from registered images obtained from Cone Beam Computed Tomography (CBCT) and a photogrammetric sensor are used to track three-dimensional shape variations of orthodontic patients before and after their treatments. The methodology consists of five main steps: (1) the patient's bone and skin shapes are measured in 3D using the fusion of images from a CBCT and a photogrammetric sensor. (2) The bone shape is extracted from the CBCT data using a standard marching cube algorithm. (3) The bone and skin shape measurements are registered using titanium targets located on the head of the patient. (4) Using a manual segmentation technique the head and lower jaw geometry are extracted separately to deal with jaw motion at the different record visits. (5) Using natural features of the upper head the two datasets are then registered with each other and then compared to evaluate bone, teeth, and skin displacements before and after treatments. This procedure is now used at the University of Alberta orthodontic clinic.

  7. Three-dimensional renal CT angiography for guiding segmental renal artery clamping during laparoscopic partial nephrectomy

    International Nuclear Information System (INIS)

    Xu, Yi; Shao, Pengfei; Zhu, Xiaomei; Lv, Qiang; Liu, Wangyan; Xu, Hai; Zhu, Yinsu; Yang, Guangyu; Tang, Lijun; Yin, Changjun

    2013-01-01

    Aim: To evaluate the effectiveness of three-dimensional (3D) renal computed tomography angiography (CTA) in guiding segmental renal artery clamping during laparoscopic partial nephrectomy (LPN). Materials and methods: Forty-three patients with renal tumours undergoing renal CTA before LPN were retrospectively enrolled in this study. 3D arteriogram reconstructed images were created to identify the renal tumour-supplying arteries. The number and location of these targeted vessels were annotated on 3D images preoperatively and compared with the clamped vessels during LPN. The consistency between target vessels annotated at CTA and clamped arteries at LPN was compared both using a patient-based analysis and vessel-based analysis. The χ 2 test was applied to analyse the influence of tumour size, location, and growth pattern on the number of clamped segmental renal branches. Results: On patient-based analysis, the number of targeted vessels was consistent with the clamped vessels during LPN in 33 of 43 patients. On vessel-based analysis, 56 of 65 target vessels annotated at CTA were clamped during LPN. More segmental renal branches (p = 0.04) were clamped in patients with tumours of larger size. Tumour location and growth pattern had no association with the number of clamped segmental branches during LPN. Conclusion: High-quality CTA images and 3D reconstruction images can detect detailed information of tumour-supplying arteries to renal tumours. 3D renal CTA is an effective way to guide segmental renal artery clamping during LPN

  8. Quantification of pneumothorax volume on chest radiographs: comparison between the collins' and the axel's methods with three-dimensional CT as the standard of reference

    International Nuclear Information System (INIS)

    Lee, Chang Keun; Kim, Hyung Jin; Lee, Kyung Hee; Kim, Joung Taek; Kim, Kwang Ho; Suh, Chang Hae; Han, Heon

    1999-01-01

    The purpose of this study was twofold. In a preliminary study, we evaluated the accuracy of 3-D (three-dimensional) CT for the estimation of pneumothorax volume and for providing the optimal postprocessing method for clinical study. In the clinical study, we determined which of the two methods, Collins' and Axel's, was more accurate for the estimation of pneumothorax volume, as seen on chest radiographs, using 3-D CT as the standard of reference. In the preliminary study, 3-D CT was applied to phantoms and to four patients with pneumothorax using two different postprocessing methods, manual contour delineation and thresholding. In the clinical study, 3-D CT was performed in 13 patients with pneumothorax. For the purpose of evaluating conventional radiographs, a localizer scan was used for comparing the accuracy of Collins' method with that of Axel's method, with 3-D CT as the standard of reference. The preliminary study revealed that 3-D CT estimated pneumothorax volume with great accuracy and that manual contour delineation and thresholding measured volume equally well. Because of the shorter postprocessing time required with thresholding than with manual contour delineation (5 min versus 30 min), the former was used during clinical study. The results of this indicated close correlation between the measurements obtained using Collins' method on chest radiographs and those obtained by 3-D CT(r=0.95, p 0.05). 3-D CT can estimate pneumothorax volume with great accuracy. Collins' method is superior to Axel's method for the quantification of pneumothorax volume as seen on chest radiographs

  9. Photogrammetry of the three-dimensional shape and texture of a nanoscale particle using scanning electron microscopy and free software

    International Nuclear Information System (INIS)

    Gontard, Lionel C.; Schierholz, Roland; Yu, Shicheng; Cintas, Jesús; Dunin-Borkowski, Rafal E.

    2016-01-01

    We apply photogrammetry in a scanning electron microscope (SEM) to study the three-dimensional shape and surface texture of a nanoscale LiTi_2(PO_4)_3 particle. We highlight the fact that the technique can be applied non-invasively in any SEM using free software (freeware) and does not require special sample preparation. Three-dimensional information is obtained in the form of a surface mesh, with the texture of the sample stored as a separate two-dimensional image (referred to as a UV Map). The mesh can be used to measure parameters such as surface area, volume, moment of inertia and center of mass, while the UV map can be used to study the surface texture using conventional image processing techniques. We also illustrate the use of 3D printing to visualize the reconstructed model. - Highlights: • 3D shape and surface texture of a nanoscale LiTi_2(PO_4)_3 particle. • The technique can be applied non-invasively in any SEM using freeware software. • The mesh can be used to measure parameters such as surface area, volume, moment of inertia and center of mass. • The UV map can be processed using 2D image processing software.

  10. Photogrammetry of the three-dimensional shape and texture of a nanoscale particle using scanning electron microscopy and free software

    Energy Technology Data Exchange (ETDEWEB)

    Gontard, Lionel C., E-mail: lionelcg@gmail.com [Departamento de Ciencia de los Materiales e Ingeniería Metalúrgica y Química Inorgánica, Universidad de Cádiz, Puerto Real 11510 (Spain); Faico PCT Cartuja. Edif. TI Marie Curie, C/ Leonardo da Vinci 18, 4a Planta, 41092 Sevilla (Spain); Schierholz, Roland; Yu, Shicheng [Institute of Energy and Climate Research, Fundamental Electrochemistry (IEK-9), Forschungszentrum Jülich, D-52425 Jülich (Germany); Cintas, Jesús [Servicio de Microscopía Centro de Investigación, Tecnología e Innovación (CITIUS), Universidad de Sevilla, Av. Reina Mercedes 4b, 41012 Sevilla (Spain); Dunin-Borkowski, Rafal E. [Ernst Ruska-Centre for Microscopy and Spectroscopy with Electrons and Peter Grünberg Institute, Forschungszentrum Jülich, D-52425 Jülich (Germany)

    2016-10-15

    We apply photogrammetry in a scanning electron microscope (SEM) to study the three-dimensional shape and surface texture of a nanoscale LiTi{sub 2}(PO{sub 4}){sub 3} particle. We highlight the fact that the technique can be applied non-invasively in any SEM using free software (freeware) and does not require special sample preparation. Three-dimensional information is obtained in the form of a surface mesh, with the texture of the sample stored as a separate two-dimensional image (referred to as a UV Map). The mesh can be used to measure parameters such as surface area, volume, moment of inertia and center of mass, while the UV map can be used to study the surface texture using conventional image processing techniques. We also illustrate the use of 3D printing to visualize the reconstructed model. - Highlights: • 3D shape and surface texture of a nanoscale LiTi{sub 2}(PO{sub 4}){sub 3} particle. • The technique can be applied non-invasively in any SEM using freeware software. • The mesh can be used to measure parameters such as surface area, volume, moment of inertia and center of mass. • The UV map can be processed using 2D image processing software.

  11. Three-dimensional machining of carbon nanotube forests using water-assisted scanning electron microscope processing

    Energy Technology Data Exchange (ETDEWEB)

    Rajabifar, Bahram; Maschmann, Matthew R., E-mail: MaschmannM@missouri.edu [Department of Mechanical and Aerospace Engineering, University of Missouri, Columbia, Missouri 65211 (United States); Kim, Sanha; Hart, A. John [Department of Mechanical Engineering and Laboratory for Manufacturing and Productivity, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States); Slinker, Keith [Materials and Manufacturing Directorate, AFRL/RX, Air Force Research Lab, Ohio 45433 (United States); Universal Technology Corporation, Beavercreek, Ohio 45424 (United States); Ehlert, Gregory J. [Materials and Manufacturing Directorate, AFRL/RX, Air Force Research Lab, Ohio 45433 (United States)

    2015-10-05

    We demonstrate that vertically aligned carbon nanotubes (CNTs) can be precisely machined in a low pressure water vapor ambient using the electron beam of an environmental scanning electron microscope. The electron beam locally damages the irradiated regions of the CNT forest and also dissociates the water vapor molecules into reactive species including hydroxyl radicals. These species then locally oxidize the damaged region of the CNTs. The technique offers material removal capabilities ranging from selected CNTs to hundreds of cubic microns. We study how the material removal rate is influenced by the acceleration voltage, beam current, dwell time, operating pressure, and CNT orientation. Milled cuts with depths between 0–100 microns are generated, corresponding to a material removal rate of up to 20.1 μm{sup 3}/min. The technique produces little carbon residue and does not disturb the native morphology of the CNT network. Finally, we demonstrate direct machining of pyramidal surfaces and re-entrant cuts to create freestanding geometries.

  12. Three-dimensional machining of carbon nanotube forests using water-assisted scanning electron microscope processing

    Science.gov (United States)

    Rajabifar, Bahram; Kim, Sanha; Slinker, Keith; Ehlert, Gregory J.; Hart, A. John; Maschmann, Matthew R.

    2015-10-01

    We demonstrate that vertically aligned carbon nanotubes (CNTs) can be precisely machined in a low pressure water vapor ambient using the electron beam of an environmental scanning electron microscope. The electron beam locally damages the irradiated regions of the CNT forest and also dissociates the water vapor molecules into reactive species including hydroxyl radicals. These species then locally oxidize the damaged region of the CNTs. The technique offers material removal capabilities ranging from selected CNTs to hundreds of cubic microns. We study how the material removal rate is influenced by the acceleration voltage, beam current, dwell time, operating pressure, and CNT orientation. Milled cuts with depths between 0-100 microns are generated, corresponding to a material removal rate of up to 20.1 μm3/min. The technique produces little carbon residue and does not disturb the native morphology of the CNT network. Finally, we demonstrate direct machining of pyramidal surfaces and re-entrant cuts to create freestanding geometries.

  13. Three-dimensional imaging modalities in endodontics

    Science.gov (United States)

    Mao, Teresa

    2014-01-01

    Recent research in endodontics has highlighted the need for three-dimensional imaging in the clinical arena as well as in research. Three-dimensional imaging using computed tomography (CT) has been used in endodontics over the past decade. Three types of CT scans have been studied in endodontics, namely cone-beam CT, spiral CT, and peripheral quantitative CT. Contemporary endodontics places an emphasis on the use of cone-beam CT for an accurate diagnosis of parameters that cannot be visualized on a two-dimensional image. This review discusses the role of CT in endodontics, pertaining to its importance in the diagnosis of root canal anatomy, detection of peri-radicular lesions, diagnosis of trauma and resorption, presurgical assessment, and evaluation of the treatment outcome. PMID:25279337

  14. Three-dimensional imaging modalities in endodontics

    Energy Technology Data Exchange (ETDEWEB)

    Mao, Teresa; Neelakantan, Prasanna [Dept. of Conservative Dentistry and Endodontics, Saveetha Dental College and Hospitals, Saveetha University, Chennai (India)

    2014-09-15

    Recent research in endodontics has highlighted the need for three-dimensional imaging in the clinical arena as well as in research. Three-dimensional imaging using computed tomography (CT) has been used in endodontics over the past decade. Three types of CT scans have been studied in endodontics, namely cone-beam CT, spiral CT, and peripheral quantitative CT. Contemporary endodontics places an emphasis on the use of cone-beam CT for an accurate diagnosis of parameters that cannot be visualized on a two-dimensional image. This review discusses the role of CT in endodontics, pertaining to its importance in the diagnosis of root canal anatomy, detection of peri-radicular lesions, diagnosis of trauma and resorption, presurgical assessment, and evaluation of the treatment outcome.

  15. Three-dimensional imaging modalities in endodontics

    International Nuclear Information System (INIS)

    Mao, Teresa; Neelakantan, Prasanna

    2014-01-01

    Recent research in endodontics has highlighted the need for three-dimensional imaging in the clinical arena as well as in research. Three-dimensional imaging using computed tomography (CT) has been used in endodontics over the past decade. Three types of CT scans have been studied in endodontics, namely cone-beam CT, spiral CT, and peripheral quantitative CT. Contemporary endodontics places an emphasis on the use of cone-beam CT for an accurate diagnosis of parameters that cannot be visualized on a two-dimensional image. This review discusses the role of CT in endodontics, pertaining to its importance in the diagnosis of root canal anatomy, detection of peri-radicular lesions, diagnosis of trauma and resorption, presurgical assessment, and evaluation of the treatment outcome

  16. Three-dimensional CT features of occipital squama normal anatomy, anatomic variations and fractures

    International Nuclear Information System (INIS)

    Liu Jungang; Li Xin; Wang Chunxiang; Zhang Lin; Guo Wanhua

    2013-01-01

    Objective: To evaluate 3D CT features of normal anatomy, anatomic variations and fractures of occipital squama. Methods: The 3D CT features on MIP, VR images were analyzed retrospectively in 589 pediatric cases. The normal anatomy, anatomic variations and fractures of occipital squama were observed respectively, and the differential diagnostic features including the individual location, appearance and extension were analyzed. Results: Four hundred and thirty-three patients (75.2%) showed normal anatomy, including 154 patients with adult occipital anatomical features, 279 patients with posterior intraoccipital synchondrosis, and 37 patients with Kerckring-supraoccipital synchondrosis. When cases with recent trauma history were excluded, 113 patients (19.1%) showed anatomic variants, including unpenetrating sutures and penetrating sutures. The former could be subdivided to Mendosal sutures in 23 cases, superior median fissures in 19 cases, and midline supraoccipital fissures in 4 cases, while the latter could be subdivided to the interparietal bone variations in 54 cases, wormian bones in 23 cases, and accessory bones in 7 cases. Two or more variations coexisted in 33 cases. The occipital squama fractures were shown in 34 cases (5.6%), including linear fractures in 27 cases, comminuted fractures in 3 cases, with depression fracture in one case, separation of cranial sutures in 3 cases, and other fractures associated with variants in 3 cases. The fractures were sharp, or jagged, without limitation of the occification. Conclusion: There are different 3D CT features of normal anatomy, anatomic variations and fractures of occipital squama in children, which are important for making the accurate diagnosis. (authors)

  17. A hybrid scanning force and light microscope for surface imaging and three-dimensional optical sectioning in differential interference contrast.

    Science.gov (United States)

    Stemmer, A

    1995-04-01

    The design of a scanned-cantilever-type force microscope is presented which is fully integrated into an inverted high-resolution video-enhanced light microscope. This set-up allows us to acquire thin optical sections in differential interference contrast (DIC) or polarization while the force microscope is in place. Such a hybrid microscope provides a unique platform to study how cell surface properties determine, or are affected by, the three-dimensional dynamic organization inside the living cell. The hybrid microscope presented in this paper has proven reliable and versatile for biological applications. It is the only instrument that can image a specimen by force microscopy and high-power DIC without having either to translate the specimen or to remove the force microscope. Adaptation of the design features could greatly enhance the suitability of other force microscopes for biological work.

  18. The Osteometry of Equine Third Phalanx by the Use of Three-Dimensional Scanning: New Measurement Possibilities

    Directory of Open Access Journals (Sweden)

    Sławomir Paśko

    2017-01-01

    Full Text Available This study consisted in analyzing the asymmetry between bilateral third phalanges (coffin bones in cold-blood horses based on the angle range of the plantar margin of the bone. The study employed a scanner projecting a hybrid set of images, consisting of sinusoidal stripes preceded by a Gray code sequence. As it turned out, three-dimensional scanning can be used to effectively determine the angle range for a selected portion of the studied bone. This provides broad possibilities for osteometric studies, as it enables the determination of angle distribution in a given fragment. The results obtained indicate a weak correlation between age and bilateral third-phalanx asymmetry in terms of the angle range of the plantar margins and no correlation between body weight and the asymmetry described.

  19. Three-dimensional characterization of pigment dispersion in dried paint films using focused ion beam-scanning electron microscopy.

    Science.gov (United States)

    Lin, Jui-Ching; Heeschen, William; Reffner, John; Hook, John

    2012-04-01

    The combination of integrated focused ion beam-scanning electron microscope (FIB-SEM) serial sectioning and imaging techniques with image analysis provided quantitative characterization of three-dimensional (3D) pigment dispersion in dried paint films. The focused ion beam in a FIB-SEM dual beam system enables great control in slicing paints, and the sectioning process can be synchronized with SEM imaging providing high quality serial cross-section images for 3D reconstruction. Application of Euclidean distance map and ultimate eroded points image analysis methods can provide quantitative characterization of 3D particle distribution. It is concluded that 3D measurement of binder distribution in paints is effective to characterize the order of pigment dispersion in dried paint films.

  20. In Vivo CT Direct Volume Rendering: A Three-Dimensional Anatomical Description of the Heart

    International Nuclear Information System (INIS)

    Cutroneo, Giuseppina; Bruschetta, Daniele; Trimarchi, Fabio; Cacciola, Alberto; Cinquegrani, Maria; Duca, Antonio; Rizzo, Giuseppina; Alati, Emanuela; Gaeta, Michele; Milardi, Demetrio

    2016-01-01

    Since cardiac anatomy continues to play an important role in the practice of medicine and in the development of medical devices, the study of the heart in three dimensions is particularly useful to understand its real structure, function and proper location in the body. This study demonstrates a fine use of direct volume rendering, processing the data set images obtained by Computed Tomography (CT) of the heart of 5 subjects with age range between 18 and 42 years (2 male, 3 female), with no history of any overt cardiac disease. The cardiac structure in CT images was first extracted from the thorax by marking manually the regions of interest on the computer, and then it was stacked to create new volumetric data. The use of a specific algorithm allowed us to observe with a good perception of depth the heart and the skeleton of the thorax at the same time. Besides, in all examined subjects, it was possible to depict its structure and its position within the body and to study the integrity of papillary muscles, the fibrous tissue of cardiac valve and chordae tendineae and the course of coronary arteries. Our results demonstrated that one of the greatest advantages of algorithmic modifications of direct volume rendering parameters is that this method provides much necessary information in a single radiologic study. It implies a better accuracy in the study of the heart, being complementary to other diagnostic methods and facilitating the therapeutic plans

  1. Three-dimensional automatic computer-aided evaluation of pleural effusions on chest CT images

    Science.gov (United States)

    Bi, Mark; Summers, Ronald M.; Yao, Jianhua

    2011-03-01

    The ability to estimate the volume of pleural effusions is desirable as it can provide information about the severity of the condition and the need for thoracentesis. We present here an improved version of an automated program to measure the volume of pleural effusions using regular chest CT images. First, the lungs are segmented using region growing, mathematical morphology, and anatomical knowledge. The visceral and parietal layers of the pleura are then extracted based on anatomical landmarks, curve fitting and active contour models. The liver and compressed tissues are segmented out using thresholding. The pleural space is then fitted to a Bezier surface which is subsequently projected onto the individual two-dimensional slices. Finally, the volume of the pleural effusion is quantified. Our method was tested on 15 chest CT studies and validated against three separate manual tracings. The Dice coefficients were 0.74+/-0.07, 0.74+/-0.08, and 0.75+/-0.07 respectively, comparable to the variation between two different manual tracings.

  2. Validation of the blurring of a small object on CT images calculated on the basis of three-dimensional spatial resolution

    International Nuclear Information System (INIS)

    Okubo, Masaki; Wada, Shinichi; Saito, Masatoshi

    2005-01-01

    We determine three-dimensional (3D) blurring of a small object on computed tomography (CT) images calculated on the basis of 3D spatial resolution. The images were characterized by point spread function (PSF), line spread function (LSF) and slice sensitivity profile (SSP). In advance, we systematically arranged expressions in the model for the imaging system to calculate 3D images under various conditions of spatial resolution. As a small object, we made a blood vessel phantom in which the direction of the vessel was not parallel to either the xy scan-plane or the z-axis perpendicular to the scan-plane. Therefore, when scanning the phantom, non-sharpness must be induced in all axes of the image. To predict the image blurring of the phantom, 3D spatial resolution is essential. The LSF and SSP were measured on our scanner, and two-dimensional (2D) PSF in the scan-plane was derived from the LSF by solving an integral equation. We obtained 3D images by convolving the 3D object-function of the phantom with both 2D PSF and SSP, corresponding to the 3D convolution. Calculated images showed good agreement with scanned images. Our technique of determining 3D blurring offers an accuracy advantage in 3D shape (size) and density measurements of small objects. (author)

  3. Documentation and analysis of traumatic injuries in clinical forensic medicine involving structured light three-dimensional surface scanning versus photography.

    Science.gov (United States)

    Shamata, Awatif; Thompson, Tim

    2018-05-10

    Non-contact three-dimensional (3D) surface scanning has been applied in forensic medicine and has been shown to mitigate shortcoming of traditional documentation methods. The aim of this paper is to assess the efficiency of structured light 3D surface scanning in recording traumatic injuries of live cases in clinical forensic medicine. The work was conducted in Medico-Legal Centre in Benghazi, Libya. A structured light 3D surface scanner and ordinary digital camera with close-up lens were used to record the injuries and to have 3D and two-dimensional (2D) documents of the same traumas. Two different types of comparison were performed. Firstly, the 3D wound documents were compared to 2D documents based on subjective visual assessment. Additionally, 3D wound measurements were compared to conventional measurements and this was done to determine whether there was a statistical significant difference between them. For this, Friedman test was used. The study established that the 3D wound documents had extra features over the 2D documents. Moreover; the 3D scanning method was able to overcome the main deficiencies of the digital photography. No statistically significant difference was found between the 3D and conventional wound measurements. The Spearman's correlation established strong, positive correlation between the 3D and conventional measurement methods. Although, the 3D surface scanning of the injuries of the live subjects faced some difficulties, the 3D results were appreciated, the validity of 3D measurements based on the structured light 3D scanning was established. Further work will be achieved in forensic pathology to scan open injuries with depth information. Crown Copyright © 2018. Published by Elsevier Ltd. All rights reserved.

  4. Precision of three-dimensional CT-assisted model production in the maxillofacial area

    International Nuclear Information System (INIS)

    Solar, P.; Ulm, C.; Lill, W.; Imhof, H.; Watzek, G.; Blahout, R.; Gruber, H.; Matejka, M.

    1992-01-01

    Individual skull model fabrication was introduced into preoperative diagnostics in maxillofacial surgery in the mid-1980s. The aim of the present study was to collect information on the reproducibility of a skull model milled from hardened polyurethane foam. This model was based on the CT data of a real skull. Twenty comparative studies were carried out on both the model and the original skull, the model showing an average inaccuracy of 1.6 mm. The deviations ranged between 0.0 and 3.6 mm; the general trend favouring enlargements. The total deviation of the model as compared to the original skull was 1.8%. A convincing aspect of the model, which cannot be obtained by any other method, is its plasticity and the possibility of 3D orientation on a lifesize model. This new method is already used in preoperative planning of corrections of post-traumatic defects and craniofacial deformities as well as in tumour surgery. (orig.)

  5. Automated extraction of pleural effusion in three-dimensional thoracic CT images

    Science.gov (United States)

    Kido, Shoji; Tsunomori, Akinori

    2009-02-01

    It is important for diagnosis of pulmonary diseases to measure volume of accumulating pleural effusion in threedimensional thoracic CT images quantitatively. However, automated extraction of pulmonary effusion correctly is difficult. Conventional extraction algorithm using a gray-level based threshold can not extract pleural effusion from thoracic wall or mediastinum correctly, because density of pleural effusion in CT images is similar to those of thoracic wall or mediastinum. So, we have developed an automated extraction method of pulmonary effusion by use of extracting lung area with pleural effusion. Our method used a template of lung obtained from a normal lung for segmentation of lungs with pleural effusions. Registration process consisted of two steps. First step was a global matching processing between normal and abnormal lungs of organs such as bronchi, bones (ribs, sternum and vertebrae) and upper surfaces of livers which were extracted using a region-growing algorithm. Second step was a local matching processing between normal and abnormal lungs which were deformed by the parameter obtained from the global matching processing. Finally, we segmented a lung with pleural effusion by use of the template which was deformed by two parameters obtained from the global matching processing and the local matching processing. We compared our method with a conventional extraction method using a gray-level based threshold and two published methods. The extraction rates of pleural effusions obtained from our method were much higher than those obtained from other methods. Automated extraction method of pulmonary effusion by use of extracting lung area with pleural effusion is promising for diagnosis of pulmonary diseases by providing quantitative volume of accumulating pleural effusion.

  6. Three dimensional analysis of CT image on naso-maxillary complex in cleft lip and palate patients

    International Nuclear Information System (INIS)

    Ma, Rong-Rong

    1994-01-01

    This study was designed to clarify the three dimensional features of naso-maxillary complex in cleft lip and palate (CLP) by using computed tomography (CT) and to examine its change following an upper dental arch expansion. Sequential CT images with 2mm-thickness were obtained for 11 unilateral CLP boys (UCLP), 6 bilateral CLP boys (BCLP) and 4 boys without cleft (non-cleft). Additionally, two serial sets of upper dental cast before and after dental arch expansion coupled with CT images in UCLP were used to evaluate the effect of dental arch expansion on the naso-maxillary complex. UCLP demonstrated a remarkable naso-maxillary deformity characterized by a decreased volume of maxillary sinus in comparison with the non-cleft patients. Both the volume and shape of nasal cavity were significantly different between the cleft and non cleft side. Naso-maxillary morphology of BCLP, however, was similar to that of the non cleft except for the decreased volume of alveolar arch. Comparative study of UCLP and BCLP showed a significant difference in naso-maxillary morphology. There were some significant correlations between the dental arch expansion and change of each naso-maxillary component, suggesting the effect of expansion stress on the naso-maxillary complex in UCLP. However, deformation caused by expansion stress varied, depending on each component of the naso-maxillary complex. (author) 61 refs

  7. Reduction of metal artifact in three-dimensional computed tomography (3D CT) with dental impression materials.

    Science.gov (United States)

    Park, W S; Kim, K D; Shin, H K; Lee, S H

    2007-01-01

    Metal Artifact still remains one of the main drawbacks in craniofacial Three-Dimensional Computed Tomography (3D CT). In this study, we tried to test the efficacy of additional silicone dental impression materials as a "tooth shield" for the reduction of metal artifact caused by metal restorations and orthodontic appliances. 6 phantoms with 4 teeth were prepared for this in vitro study. Orthodontic bracket, bands and amalgam restorations were placed in each tooth to reproduce various intraoral conditions. Standardized silicone shields were fabricated and placed around the teeth. CT image acquisition was performed with and without silicone shields. Maximum value, mean, and standard deviation of Hounsfield Units (HU) were compared with the presence of silicone shields. In every situation, metal artifacts were reduced in quality and quantity when silicone shields are used. Amalgam restoration made most serious metal artifact. Silicone shields made by dental impression material might be effective way to reduce the metal artifact caused by dental restoration and orthodontic appliances. This will help more excellent 3D image from 3D CT in craniofacial area.

  8. Three dimensional analysis of CT image on naso-maxillary complex in cleft lip and palate patients

    Energy Technology Data Exchange (ETDEWEB)

    Ma, Rong-Rong [Tokyo Medical and Dental Univ. (Japan). School of Dentistry

    1994-12-01

    This study was designed to clarify the three dimensional features of naso-maxillary complex in cleft lip and palate (CLP) by using computed tomography (CT) and to examine its change following an upper dental arch expansion. Sequential CT images with 2mm-thickness were obtained for 11 unilateral CLP boys (UCLP), 6 bilateral CLP boys (BCLP) and 4 boys without cleft (non-cleft). Additionally, two serial sets of upper dental cast before and after dental arch expansion coupled with CT images in UCLP were used to evaluate the effect of dental arch expansion on the naso-maxillary complex. UCLP demonstrated a remarkable naso-maxillary deformity characterized by a decreased volume of maxillary sinus in comparison with the non-cleft patients. Both the volume and shape of nasal cavity were significantly different between the cleft and non cleft side. Naso-maxillary morphology of BCLP, however, was similar to that of the non cleft except for the decreased volume of alveolar arch. Comparative study of UCLP and BCLP showed a significant difference in naso-maxillary morphology. There were some significant correlations between the dental arch expansion and change of each naso-maxillary component, suggesting the effect of expansion stress on the naso-maxillary complex in UCLP. However, deformation caused by expansion stress varied, depending on each component of the naso-maxillary complex. (author) 61 refs.

  9. SU-F-J-57: Effectiveness of Daily CT-Based Three-Dimensional Image Guided and Adaptive Proton Therapy

    Energy Technology Data Exchange (ETDEWEB)

    Moriya, S [University of Tsukuba, Tsukuba, Ibaraki (Japan); National Cancer Center, Kashiwa, Chiba (Japan); Tachibana, H; Hotta, K; Baba, H; Kohno, R; Akimoto, T [National Cancer Center, Kashiwa, Chiba (Japan); Nakamura, N [National Cancer Center Hospital East, Kashiwa, Chiba (Japan); Miyakawa, S; Kurosawa, T [Komazawa University, Setagaya, Tokyo (Japan)

    2016-06-15

    Purpose: Daily CT-based three-dimensional image-guided and adaptive (CTIGRT-ART) proton therapy system was designed and developed. We also evaluated the effectiveness of the CTIGRT-ART. Methods: Retrospective analysis was performed in three lung cancer patients: Proton treatment planning was performed using CT image datasets acquired by Toshiba Aquilion ONE. Planning target volume and surrounding organs were contoured by a well-trained radiation oncologist. Dose distribution was optimized using 180-deg. and 270-deg. two fields in passive scattering proton therapy. Well commissioned Simplified Monte Carlo algorithm was used as dose calculation engine. Daily consecutive CT image datasets was acquired by an in-room CT (Toshiba Aquilion LB). In our in-house program, two image registrations for bone and tumor were performed to shift the isocenter using treatment CT image dataset. Subsequently, dose recalculation was performed after the shift of the isocenter. When the dose distribution after the tumor registration exhibits change of dosimetric parameter of CTV D90% compared to the initial plan, an additional process of was performed that the range shifter thickness was optimized. Dose distribution with CTV D90% for the bone registration, the tumor registration only and adaptive plan with the tumor registration was compared to the initial plan. Results: In the bone registration, tumor dose coverage was decreased by 16% on average (Maximum: 56%). The tumor registration shows better coverage than the bone registration, however the coverage was also decreased by 9% (Maximum: 22%) The adaptive plan shows similar dose coverage of the tumor (Average: 2%, Maximum: 7%). Conclusion: There is a high possibility that only image registration for bone and tumor may reduce tumor coverage. Thus, our proposed methodology of image guidance and adaptive planning using the range adaptation after tumor registration would be effective for proton therapy. This research is partially supported

  10. Three-dimensional whole-brain perfused blood volume imaging with multimodal CT for evaluation of acute ischaemic stroke

    International Nuclear Information System (INIS)

    Lu, J.; Zhang, M.; Cao, Y.; Ma, Q.; Chen, J.; Ji, X.; Li, K.

    2011-01-01

    Aim: To determine the diagnostic value of integrating three-dimensional perfused blood volume (3D PBV) with multimodal computed tomography (CT) [non-enhanced CT (NECT), CT perfusion (CTP), and CT angiography (CTA)] in acute ischaemic stroke. Materials and methods: NECT, CTP, and CTA were performed in 25 acute ischaemic stroke patients. The ischaemia detection rate of 3D PBV was compared with the results of baseline NECT and CTP. The correlation of ischaemic lesion volume between 3D PBV, CTP images, and follow-up NECT were analysed. Results: NECT demonstrated ischaemic signs in 12 of 25 patients with proven infarction. CTP maps of cerebral blood flow (CBF), cerebral blood volume (CBV), and time to peak (TTP) all demonstrated perfusion deficits in 21 of 25 patients. However, 3D PBV demonstrated perfusion deficits in all of the 25 patients. Among the 25 patients, a strong correlation was found between PBV and the follow-up NECT infarct (r = 0.858). The correlation between CTP and the follow-up NECT infarct as following: CBF (r = 0.718), CBV (r = 0.785), and TTP (r = 0.569). In 14 thrombolytic patients, strong correlation was found between the ischaemic volume on 3D PBV and follow-up NECT (r = 0.798). Conclusion: In acute stroke patients, the combination of 3D PBV and multimodal CT (NECT, CTP, and CTA) can improve the detection rate of ischaemia and enable assessment of the full extent of ischaemia, which correlates well with follow-up NECT.

  11. A three-dimensional reconstruction algorithm for an inverse-geometry volumetric CT system

    International Nuclear Information System (INIS)

    Schmidt, Taly Gilat; Fahrig, Rebecca; Pelc, Norbert J.

    2005-01-01

    An inverse-geometry volumetric computed tomography (IGCT) system has been proposed capable of rapidly acquiring sufficient data to reconstruct a thick volume in one circular scan. The system uses a large-area scanned source opposite a smaller detector. The source and detector have the same extent in the axial, or slice, direction, thus providing sufficient volumetric sampling and avoiding cone-beam artifacts. This paper describes a reconstruction algorithm for the IGCT system. The algorithm first rebins the acquired data into two-dimensional (2D) parallel-ray projections at multiple tilt and azimuthal angles, followed by a 3D filtered backprojection. The rebinning step is performed by gridding the data onto a Cartesian grid in a 4D projection space. We present a new method for correcting the gridding error caused by the finite and asymmetric sampling in the neighborhood of each output grid point in the projection space. The reconstruction algorithm was implemented and tested on simulated IGCT data. Results show that the gridding correction reduces the gridding errors to below one Hounsfield unit. With this correction, the reconstruction algorithm does not introduce significant artifacts or blurring when compared to images reconstructed from simulated 2D parallel-ray projections. We also present an investigation of the noise behavior of the method which verifies that the proposed reconstruction algorithm utilizes cross-plane rays as efficiently as in-plane rays and can provide noise comparable to an in-plane parallel-ray geometry for the same number of photons. Simulations of a resolution test pattern and the modulation transfer function demonstrate that the IGCT system, using the proposed algorithm, is capable of 0.4 mm isotropic resolution. The successful implementation of the reconstruction algorithm is an important step in establishing feasibility of the IGCT system

  12. The study on three-dimensional measurement of the Human Eustachian tube examined by Multislice CT

    International Nuclear Information System (INIS)

    Yoshioka, Satoshi; Naito, Kensei; Fujii, Naoko; Katada, Kazuhiro; Takeuchi, Kenji

    2007-01-01

    Morphological aberration of the Eustachian tube is a significant factor of various middle ear diseases. Traditionally, cadaveric specimens have been used for studies on the morphology of Eustachian tubes. However, this approach was not too efficient, as samples were limited in number as they were difficult to obtain, and biological conditions were not reflected due to rigor mortis and atrophy during specimen preparation. We thus decided to use Multi-Slice CT (MSCT) to perform 3-dimensional (3-D) anatomic measurements of the Eustachian tube. MSCT has benefits of isotropy and high resolution, and it is useful in preparing images of any plane. Forty-eight adults were studied. For the purpose of measurement, various anatomic indices were carefully and precisely defined to identify each area on the image. Calculations based on each coordinate value enabled the measurement of length, diameter and angle of the Eustachian tube of normal adults. Therefore, measurements of the Eustachian tube, which were traditionally difficult as it is located in the deep part of the cranium, were simplified in many specimens. Mean value of total length was 39.2±3.2 mm, cartilage part length of the tube 30.0±2.7 mm and bony part 9.2±1.6 mm. Mean values of diameter of tympanic orifice were 5.2 x 3.2 mm, and pharyngeal orifice 9.7 x 4.4 mm. Mean value of angle between bony part and cartilage part was 160.9±13.6 degrees. This approach to anatomic measurement is expected to contribute greatly to investigation on various middle ear diseases. (author)

  13. Creation and evaluation of complementary composite three-dimensional image in various brain diseases. An application of three-dimensional brain SPECT image and three-dimensional CT image

    International Nuclear Information System (INIS)

    Seiki, Yoshikatsu; Shibata, Iekado; Mito, Toshiaki; Sugo, Nobuo

    2000-01-01

    The purpose of this study was to develop 3D composite images for use in functional and anatomical evaluation of various cerebral pathologies. Imaging studies were performed in normal volunteers, patients with hydrocephalus and patients with brain tumor (meningioma and metastatic tumor) using a three-detector SPECT system (Prism 3000) and helical CT scanner (Xvigor). 123 I-IMP was used in normal volunteers and patients with hydrocephalus, and 201 TLCL in patients with brain tumor. An Application Visualization System-Medical Viewer (AVS-MV) was used on a workstation (Titan 2) to generate 3D images. A new program was developed by synthesizing surface rendering and volume rendering techniques. The clinical effects of shunt operations were successfully evaluated in patients with hydrocephalus by means of translucent 3D images of the deep brain. Changes in the hypoperfusion area around the cerebral ventricle were compared with morphological changes in the cerebral ventricle on CT. In addition to the information concerning the characteristics of brain tumors and surrounding edemas, hemodynamic changes and changeable hypoperfusion areas around the tumors were visualized on 3D composite CT and SPECT images. A new method of generating 3D composite images of CT and SPECT was developed by combining graphic data from different systems on the same workstation. Complementary 3D composite images facilitated quantitative analysis of brain volume and functional analysis in various brain diseases. (author)

  14. Three-dimensional image analysis of a head of the giant panda by the cone-beam type CT

    International Nuclear Information System (INIS)

    Endo, H.; Komiya, T.; Narushima, E.; Suzuki, N.

    2002-01-01

    The cone-beam type CT (Computed Tomography) enabled us to collect the three-dimensional (3D) digitalized data directly from the animal carcass. In this study, we applied the techniques of the cone-beam type CT for a carcass head of the giant panda (Ailuropoda melanoleuca) to obtain the 3D images easily without reconstruction process, and could morphologically examine the sections from the 3D data by means of non-destructive observations. The important results of the study represent the two following points. 1) We could show the morphological relationships between the muscles of mastication and the mandible in non-destructive status from the 3D data. The exact position of the coronoid process could be recognized in the rostro-lateral space of the temporal fossa. 2) By the serial sections from the 3D data sets, the morphological characteristics in the nasal cavity were detailed with high resolution in this rare species. The nasal concha was well-developed in the nasal cavity. The ethmoidal labyrinth was encountered immediately caudal to the nasal cavity and close to the region of the olfactory bulb. The ethmoidal labyrinth consisted of the complicated osseous structure in this area. The data will be useful to discuss the olfactory function in the reproduction behavior of this species

  15. Three-dimensional fracture visualisation of multidetector CT of the skull base in trauma patients: comparison of three reconstruction algorithms

    International Nuclear Information System (INIS)

    Ringl, Helmut; Schernthaner, Ruediger; Philipp, Marcel O.; Metz-Schimmerl, Sylvia; Czerny, Christian; Weber, Michael; Steiner-Ringl, Andrea; Peloschek, Philipp; Herold, Christian J.; Schima, Wolfgang; Gaebler, Christian

    2009-01-01

    The purpose of this study was to retrospectively assess the detection rate of skull-base fractures for three different three-dimensional (3D) reconstruction methods of cranial CT examinations in trauma patients. A total of 130 cranial CT examinations of patients with previous head trauma were subjected to 3D reconstruction of the skull base, using solid (SVR) and transparent (TVR) volume-rendering technique and maximum intensity projection (MIP). Three radiologists independently evaluated all reconstructions as well as standard high-resolution multiplanar reformations (HR-MPRs). Mean fracture detection rates for all readers reading rotating reconstructions were 39, 36, 61 and 64% for SVR, TVR, MIP and HR-MPR respectively. Although not significantly different from HR-MPR with respect to sensitivity (P = 0.9), MIP visualised 18% of fractures that were not reported in HR-MPR. Because of the relatively low detection rate using HR-MPRs alone, we recommend reading MIP reconstructions in addition to the obligatory HR-MPRs to improve fracture detection. (orig.)

  16. Extent of emphysema estimated by the three dimensional CT (3D-CT) predicts pulmonary dysfunction in patients with COPD

    International Nuclear Information System (INIS)

    Fujita, Etsuo; Inoue, Yoshikazu; Tanaka Isao

    2003-01-01

    We assessed the extent of emphysematous area by the 3D-CT in 35 chronic stable patients (age 66.5±8.9 yrs). And we evaluated the data from the total lung volume estimated by the 3D-CT, % low attenuation area below -950 HU (%LAA) and pulmonary function tests (PFT). Total lung volume estimated by 3D-CT was correlated with total lung capacity (TLC) by PFT (r=0.736, p<0.0005). The % LAA correlated with forced expiratory volume (FEV) 1% (r=-0.716, p<0.001). We concluded that the 3D-CT is the excellent method of evaluating the extent of emphysema without effort. (author)

  17. Three dimensional reflection velocity analysis based on velocity model scan; Model scan ni yoru sanjigen hanshaha sokudo kaiseki

    Energy Technology Data Exchange (ETDEWEB)

    Minegishi, M; Tsuru, T [Japan National Oil Corp., Tokyo (Japan); Matsuoka, T [Japan Petroleum Exploration Corp., Tokyo (Japan)

    1996-05-01

    Introduced herein is a reflection wave velocity analysis method using model scanning as a method for velocity estimation across a section, the estimation being useful in the construction of a velocity structure model in seismic exploration. In this method, a stripping type analysis is carried out, wherein optimum structure parameters are determined for reflection waves one after the other beginning with those from shallower parts. During this process, the velocity structures previously determined for the shallower parts are fixed and only the lowest of the layers undergoing analysis at the time is subjected to model scanning. To consider the bending of ray paths at each velocity boundaries involving shallower parts, the ray path tracing method is utilized for the calculation of the reflection travel time curve for the reflection surface being analyzed. Out of the reflection wave travel time curves calculated using various velocity structure models, one that suits best the actual reflection travel time is detected. The degree of matching between the calculated result and actual result is measured by use of data semblance in a time window provided centering about the calculated reflective wave travel time. The structure parameter is estimated on the basis of conditions for the maximum semblance. 1 ref., 4 figs.

  18. Predicting Peri-Device Leakage of Left Atrial Appendage Device Closure Using Novel Three-Dimensional Geometric CT Analysis.

    Science.gov (United States)

    Chung, Hyemoon; Jeon, Byunghwan; Chang, Hyuk-Jae; Han, Dongjin; Shim, Hackjoon; Cho, In Jeong; Shim, Chi Young; Hong, Geu-Ru; Kim, Jung-Sun; Jang, Yangsoo; Chung, Namsik

    2015-12-01

    After left atrial appendage (LAA) device closure, peri-device leakage into the LAA persists due to incomplete occlusion. We hypothesized that pre-procedural three-dimensional (3D) geometric analysis of the interatrial septum (IAS) and LAA orifice can predict this leakage. We investigated the predictive parameters of LAA device closure obtained from baseline cardiac computerized tomography (CT) using a novel 3D analysis system. We conducted a retrospective study of 22 patients who underwent LAA device closure. We defined peri-device leakage as the presence of a Doppler signal inside the LAA after device deployment (group 2, n = 5) compared with patients without peri-device leakage (group 1, n = 17). Conventional parameters were measured by cardiac CT. Angles θ and φ were defined between the IAS plane and the line, linking the LAA orifice center and foramen ovale. Group 2 exhibited significantly better left atrial (LA) function than group 1 (p = 0.031). Pre-procedural θ was also larger in this group (41.9° vs. 52.3°, p = 0.019). The LAA cauliflower-type morphology was more common in group 2. Overall, the patients' LA reserve significantly decreased after the procedure (21.7 mm(3) vs. 17.8 mm(3), p = 0.035). However, we observed no significant interval changes in pre- and post-procedural values of θ and φ in either group (all p > 0.05). Angles between the IAS and LAA orifice might be a novel anatomical parameter for predicting peri-device leakage after LAA device closure. In addition, 3D CT analysis of the LA and LAA orifice could be used to identify clinically favorable candidates for LAA device closure.

  19. Two and three-dimensional morphometric analysis of trabecular bone using X-ray microtomography (μCT)

    International Nuclear Information System (INIS)

    Silva, Alessandro Marcio Hakme da; Silva, Orivaldo Lopes da; Silva Junior, Nelson Ferreira da; Alves, Jose Marcos

    2014-01-01

    Introduction: trabecular bones have a porous microstructure and can be modeled as linear elastic solids, heterogeneous and anisotropic. In the literature, few investigations have compared the two- dimensional (2D) and three-dimensional (3D) morphometric analyses of cancellous bone. Methods: In this investigation eighteen cylindrical samples of cancellous bone (10 mm of diameter and 20 mm of height) were obtained from six bovine head femurs, with similar values for the weight and age, of the same race and gender. The samples were harvested and freeze at - 20 °C before carrying out the micro CT analysis. The CT-Analyzer software was used to measure in three directions (superior-inferior, lateral-medial and anterior-posterior) parameters such as trabecular thickness, trabecular separation, trabecular number and the eigenvalues of the fabric tensor (M). Results: the Comparison of 2D and 3D analyses for the parameters: 2D (plate model) trabecular thickness, trabecular separation and trabecular number were statistically different (p = 0) showing that measurements are not similar to the 3D ones. However, 2D (rod model) trabecular thickness and 3D trabecular thickness measurements presented no significant difference (p = 0.26). The eigenvalues show that the bovine trabecular microstructure has a tendency to transversally isotropic symmetry. Discussion: The method proved to be quite interesting for the characterization of the bone structure through 3D measurements of trabecular bone morphometric parameters in the three possible directions of loading. The results show that x-ray microtomography (μCT) is a technique of great potential for characterization and generating bone quality parameters for the diagnosis of bone metabolism diseases. (author)

  20. Two and three-dimensional morphometric analysis of trabecular bone using X-ray microtomography (μCT)

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Alessandro Marcio Hakme da; Silva, Orivaldo Lopes da; Silva Junior, Nelson Ferreira da, E-mail: alhakme@sc.usp.br [Universidade de Sao Paulo (EESC/FMRP/IQSC/USP), Sao Carlos, SP (Brazil); Alves, Jose Marcos [Universidade de Sao Paulo (USP), Sao Carlos, SP (Brazil). Escola de Engenharia. Departamento de Engenharia Eletrica e Computacao

    2014-07-01

    Introduction: trabecular bones have a porous microstructure and can be modeled as linear elastic solids, heterogeneous and anisotropic. In the literature, few investigations have compared the two- dimensional (2D) and three-dimensional (3D) morphometric analyses of cancellous bone. Methods: In this investigation eighteen cylindrical samples of cancellous bone (10 mm of diameter and 20 mm of height) were obtained from six bovine head femurs, with similar values for the weight and age, of the same race and gender. The samples were harvested and freeze at - 20 °C before carrying out the micro CT analysis. The CT-Analyzer software was used to measure in three directions (superior-inferior, lateral-medial and anterior-posterior) parameters such as trabecular thickness, trabecular separation, trabecular number and the eigenvalues of the fabric tensor (M). Results: the Comparison of 2D and 3D analyses for the parameters: 2D (plate model) trabecular thickness, trabecular separation and trabecular number were statistically different (p = 0) showing that measurements are not similar to the 3D ones. However, 2D (rod model) trabecular thickness and 3D trabecular thickness measurements presented no significant difference (p = 0.26). The eigenvalues show that the bovine trabecular microstructure has a tendency to transversally isotropic symmetry. Discussion: The method proved to be quite interesting for the characterization of the bone structure through 3D measurements of trabecular bone morphometric parameters in the three possible directions of loading. The results show that x-ray microtomography (μCT) is a technique of great potential for characterization and generating bone quality parameters for the diagnosis of bone metabolism diseases. (author)

  1. Three-dimensional reconstruction of highly complex microscopic samples using scanning electron microscopy and optical flow estimation.

    Directory of Open Access Journals (Sweden)

    Ahmadreza Baghaie

    Full Text Available Scanning Electron Microscope (SEM as one of the major research and industrial equipment for imaging of micro-scale samples and surfaces has gained extensive attention from its emerge. However, the acquired micrographs still remain two-dimensional (2D. In the current work a novel and highly accurate approach is proposed to recover the hidden third-dimension by use of multi-view image acquisition of the microscopic samples combined with pre/post-processing steps including sparse feature-based stereo rectification, nonlocal-based optical flow estimation for dense matching and finally depth estimation. Employing the proposed approach, three-dimensional (3D reconstructions of highly complex microscopic samples were achieved to facilitate the interpretation of topology and geometry of surface/shape attributes of the samples. As a byproduct of the proposed approach, high-definition 3D printed models of the samples can be generated as a tangible means of physical understanding. Extensive comparisons with the state-of-the-art reveal the strength and superiority of the proposed method in uncovering the details of the highly complex microscopic samples.

  2. Three-dimensional imaging of individual point defects using selective detection angles in annular dark field scanning transmission electron microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, Jared M.; Im, Soohyun; Windl, Wolfgang; Hwang, Jinwoo, E-mail: hwang.458@osu.edu

    2017-01-15

    We propose a new scanning transmission electron microscopy (STEM) technique that can realize the three-dimensional (3D) characterization of vacancies, lighter and heavier dopants with high precision. Using multislice STEM imaging and diffraction simulations of β-Ga{sub 2}O{sub 3} and SrTiO{sub 3}, we show that selecting a small range of low scattering angles can make the contrast of the defect-containing atomic columns substantially more depth-dependent. The origin of the depth-dependence is the de-channeling of electrons due to the existence of a point defect in the atomic column, which creates extra “ripples” at low scattering angles. The highest contrast of the point defect can be achieved when the de-channeling signal is captured using the 20–40 mrad detection angle range. The effect of sample thickness, crystal orientation, local strain, probe convergence angle, and experimental uncertainty to the depth-dependent contrast of the point defect will also be discussed. The proposed technique therefore opens new possibilities for highly precise 3D structural characterization of individual point defects in functional materials. - Highlights: • A new electron microscopy technique that can visualize 3D position of point defect is proposed. • The technique relies on the electron de-channeling signals at low scattering angles. • The technique enables precise determination of the depth of vacancies and lighter impurity atoms.

  3. CT scan of Parkinson's disease

    Energy Technology Data Exchange (ETDEWEB)

    Konishi, T; Noguchi, S; Nishitani, H [National Sanatorium of Utano, Kyoto (Japan); Kitano, H; Ikegami, Y

    1981-04-01

    In forty-eight patients with Parkinson's disease, we examined the ventricular size and the degree of cortical atrophy which were measured by the photos of CT scan and compared them with their clinical symptoms and side effects of anti-parkinsonian drugs. The ventricular size was expressed as the ventricular ratio which is the percentage of superimposed lateral ventricular area to the white and gray matter area at the slice number 2B of CT scan photos. The degree of the cortical atrophy was expressed as the sulcal numbers which were clearly visualized at the slice number 3B or 4A of CT scan photos. We used the CT scan photos of age-matched other patients which did not show definit central nervous system abnormalities. Our findings were as follows: (1) The ventricular enlargement was observed in the parkinsonian patients who showed dementia and/or Yahr's classification grades IV or V. (2) There was no correlation between the duration of this disease and the L--dopa treatments with the ventricular size and sulcal numbers. (3) The side effects of drugs such as visual hallucination were tended to be observed in the patients who showed the ventricular enlargement. (4) There was no definite correlation between the degree of cortical atrophy with clinical symptoms and side effects of various drugs. These findings suggested that the ventricular enlargement in Parkinson's disease was an important sign of dementia and the tendency of appearance of side effects of various drugs.

  4. CT scan of Parkinson's disease

    International Nuclear Information System (INIS)

    Konishi, Tetsuro; Noguchi, Sadako; Nishitani, Hiroshi; Kitano, Haruo; Ikegami, Yoshinori.

    1981-01-01

    In forty-eight patients with Parkinson's disease, we examined the ventricular size and the degree of cortical atrophy which were measured by the photos of CT scan and compared them with their clinical symptoms and side effects of anti-parkinsonian drugs. The ventricular size was expressed as the ventricular ratio which is the percentage of superimposed lateral ventricular area to the white and gray matter area at the slice number 2B of CT scan photos. The degree of the cortical atrophy was expressed as the sulcal numbers which were clearly visualized at the slice number 3B or 4A of CT scan photos. We used the CT scan photos of age-matched other patients which did not show definit central nervous system abnormalities. Our findings were as follows: (1) The ventricular enlargement was observed in the parkinsonian patients who showed dementia and/or Yahr's classification grades IV or V. (2) There was no correlation between the duration of this disease and the L--dopa treatments with the ventricular size and sulcal numbers. (3) The side effects of drugs such as visual hallucination were tended to be observed in the patients who showed the ventricular enlargement. (4) There was no definite correlation between the degree of cortical atrophy with clinical symptoms and side effects of various drugs. These findings suggested that the ventricular enlargement in Parkinson's disease was an important sign of dementia and the tendency of appearance of side effects of various drugs. (author)

  5. Usefulness of three-dimensional CT pancreatography (3D-CTP) after the balloon-ERP for pancreatic diseases

    International Nuclear Information System (INIS)

    Ueki, Toshiharu; Oishi, Yayoi; Sakaguchi, Seigo; Sakurai, Toshihiro; Yao, Tsuneyoshi; Ichimaru, Yoshihiko; Koga, Yuki; Ikeda, Seiyo

    1998-01-01

    The clinical usefulness of 3D-CTP combined with the balloon-ERP and helical-CT was discussed. Authors diagnosed 42 patients with pancreatic diseases, including 5 of pancreatic carcinoma, 3 of serous cystadenoma, 6 of muciparous pancreatic cyst, 28 of chronic pancreatitis (including 8 cases of complicated pseudocyst). The images could reconstruct three-dimensionally the tapering constriction in the main pancreatic duct for all 5 cases of pancreatic carcinoma, the exclusion in the main pancreatic duct for 3 cases of serous cystadenoma and 1 case of muciparous pancreatic cyst, the parietal irregularity for 14 cases and the smooth constriction for 9 cases in main pancreatic duct of chronic pancreatitis, the morphology of the cyst and the spatial relationship between the cyst and the pancreatic duct in 5 of 6 cases of muciparous pancreatic cyst and 7 of 8 cases of complicated pseudocyst. Furthermore, the 3D-CTP could demonstrate the branched pancreatic duct at the constriction site which was not detected by the balloon-ERP in 2 cases of chronic pancreatitis with the constriction at the main pancreatic duct, and the joining manner of cyst to the pancreatic duct which was indistinct by the balloon-ERP in 6 cases of pancreatic cyst. These results show that 3D-CTP is useful for the qualitative diagnosis and applicable for the understanding of pancreatic diseases and for the simulation of surgery. (K.H.)

  6. Detection of intracranial aneurysms using three-dimensional multidetector-row CT angiography: Is bone subtraction necessary?

    International Nuclear Information System (INIS)

    Hwang, Seung Bae; Kwak, Hyo Sung; Han, Young Min; Chung, Gyung Ho

    2011-01-01

    Purpose: The aim of this study was to evaluate the usefulness of three-dimensional CT angiography (3D CTA) with bone subtraction in a comparison with 3D CTA without bone subtraction for the detection of intracranial aneurysms. Materials and methods: Among 337 consecutive patients who had intracranial aneurysms detected on 3D CTA, 170 patients who underwent digital subtraction angiography (DSA) were included in the study. CTA was performed with a 16-slice multidetector-row CT (MDCT) scanner. We created the 3D reconstruction images with and without bone subtraction by using the volume rendering technique. Three neuroradiologists in a blinded fashion interpreted both 3D CTA images with and without bone subtraction. The diagnostic accuracy of both techniques was evaluated using the alternative free-response receiver operating characteristic (ROC) analysis. The sensitivity and positive predictive value were also evaluated. Results: A total of 200 aneurysms (size: 2-23 mm) were detected in 170 patients. The area under the receiver operating characteristic curve (Az) for 3D CTA with bone subtraction (mean, Az = 0.933) was significantly higher than that for 3D CTA without bone subtraction (mean, Az = 0.879) for all observers (P < 0.05). The sensitivity of 3D CTA with bone subtraction for three observers was 90.0, 92.0 and 92.5%, respectively, while the sensitivity of 3D CTA without bone subtraction was 83.5, 83.5 and 87.5%, respectively. No significant difference in positive predictive value was observed between the two modalities. Conclusions: 3D CTA with bone subtraction showed significantly higher diagnostic accuracy for the detection of intracranial aneurysms as compared to 3D CTA without bone subtraction.

  7. CT scan of pituitary adenomas

    International Nuclear Information System (INIS)

    Sakoda, K.; Mukada, K.; Yonezawa, M.; Matsumura, S.; Yoshimoto, H.; Mori, S.; Uozumi, T.

    1981-01-01

    CT scan is an extremely useful, almost harmless means of diagnosing pituitary adenomas. Growth hormone (GH)-secreting adenomas tend to have higher absorption coefficent in plain CT than the nonfunctioning and prolactin (PRL)-secreting adenomas. The absorption coefficent on contrast-enhanced CT does not identify the specific type of adenoma. Ring-like enhancement was observed in five nonfunctioning and four PRL-secreting adenomas with suprasellar extension, while cystic components were observed in four nonfunctioning and four PRL-secreting adenomas. In three of ten cases of PRL-secreting microadenomas, the site corresponding to the adenoma was not enhanced, whereas the normal pituitary was. A correlation exists between the size of PRL-secreting adenoma and the serum PRL level, but not between the size of GH-secreting adenomas and the serum GH level. (orig.)

  8. Phantom study on three-dimensional target volume delineation by PET/CT-based auto-contouring

    International Nuclear Information System (INIS)

    Zhang, Tiejiao; Sakaguchi, Yuichi; Mitsumoto, Katsuhiko; Mitsumoto, Tatsuya; Sasaki, Masayuki; Tachiya, Yosuke; Ohya, Nobuyoshi

    2010-01-01

    The aim of this study was to determine an appropriate threshold value for delineation of the target volume in positron emission tomography (PET)/CT and to investigate whether we could delineate a target volume by phantom studies. A phantom consisted of six spheres (φ10-37 mm) filled with 18 F solution. Data acquisition was performed PET/CT in non-motion and motion status with high 18 F solution and in non-motion status with low 18 F solution. In non-motion phantom experiments, we determined two types of threshold value, an absolute SUV (T SUV ) and a percentage of the maximum SUV (T % ). Delineation using threshold values was applied for all spheres and for selected large spheres (a diameter of 22 mm or larger). In motion phantom experiments, data acquisition was performed in a static mode (sPET) and a gated mode (gPET). CT scanning was performed with helical CT (HCT) and 4-dimentional CT (4DCT). The appropriate threshold values were aT % =27% and aT SUV =2.4 for all spheres, and sT % =30% and sT SUV =4.3 for selected spheres. For all spheres in sPET/HCT in motion, the delineated volumes were 84%-129% by the aT % and 34%-127% by the aT SUV . In gPET/4DCT in motion, the delineated volumes were 94-103% by the aT % and 51-131% by the aT SUV . For low radioactivity spheres, the delineated volumes were all underestimated. A threshold value of T % =27% was proposed for auto-contouring of lung tumors. Our results also suggested that the respiratory gated data acquisition should be performed in both PET and CT for target volume delineation. (author)

  9. Validation of an enhanced knowledge-based method for segmentation and quantitative analysis of intrathoracic airway trees from three-dimensional CT images

    International Nuclear Information System (INIS)

    Sonka, M.; Park, W.; Hoffman, E.A.

    1995-01-01

    Accurate assessment of airway physiology, evaluated in terms of geometric changes, is critically dependent upon the accurate imaging and image segmentation of the three-dimensional airway tree structure. The authors have previously reported a knowledge-based method for three-dimensional airway tree segmentation from high resolution CT (HRCT) images. Here, they report a substantially improved version of the method. In the current implementation, the method consists of several stages. First, the lung borders are automatically determined in the three-dimensional set of HRCT data. The primary airway tree is semi-automatically identified. In the next stage, potential airways are determined in individual CT slices using a rule-based system that uses contextual information and a priori knowledge about pulmonary anatomy. Using three-dimensional connectivity properties of the pulmonary airway tree, the three-dimensional tree is constructed from the set of adjacent slices. The method's performance and accuracy were assessed in five 3D HRCT canine images. Computer-identified airways matched 226/258 observer-defined airways (87.6%); the computer method failed to detect the airways in the remaining 32 locations. By visual assessment of rendered airway trees, the experienced observers judged the computer-detected airway trees as highly realistic

  10. A cone-beam computed tomography triple scan procedure to obtain a three-dimensional augmented virtual skull model appropriate for orthognathic surgery planning.

    NARCIS (Netherlands)

    Swennen, G.R.J.; Mollemans, W.; Clercq, C. De; Abeloos, J.V.S.; Lamoral, P.; Lippens, F.R.C.; Neyt, N.; Casselman, J.W.; Schutyser, F.A.C.

    2009-01-01

    The aim of this study was to present a new approach to acquire a three-dimensional virtual skull model appropriate for orthognathic surgery planning without the use of plaster dental models and without deformation of the facial soft-tissue mask. A "triple" cone-beam computed tomography (CBCT) scan

  11. Activity and three-dimensional distribution of toluene-degrading Pseudomonas putida in a multispecies biofilm assessed by quantitative in situ hybridization and scanning confocal laser microscopy

    DEFF Research Database (Denmark)

    Møller, Søren; Pedersen, Anne Rathmann; Poulsen, L.K.

    1996-01-01

    As a representative member of the toluene-degrading population in a biofilter for waste gas treatment, Pseudomonas putida was investigated with a 16S rRNA targeting probe, The three-dimensional distribution of P. putida was visualized in the biofilm matrix by scanning confocal laser microscopy...

  12. Three-dimensional visualization and characterization of bone structure using reconstructed in-vitro μCT images: A pilot study for bone microarchitecture analysis

    Energy Technology Data Exchange (ETDEWEB)

    Latief, Fourier Dzar Eljabbar, E-mail: fourier@fi.itb.ac.id [Physics of Earth and Complex Systems, Faculty of Mathematics and Natural Sciences, Institut Teknologi Bandung, Jl. Ganesha 10, Bandung 40132 (Indonesia); Dewi, Dyah Ekashanti Octorina [2Biomedical Engineering Research Division, School of Electrical Engineering and Informatics, Institut Teknologi Bandung, Jl. Ganesha 10, Bandung 40132 (Indonesia); Shari, Mohd Aliff Bin Mohd [Faculty of Electrical Engineering, Universiti Teknologi MARA Malaysia, 40000 Shah Alam, Selangor (Malaysia)

    2014-03-24

    Micro Computed Tomography (μCT) has been largely used to perform micrometer scale imaging of specimens, bone biopsies and small animals for the study of porous or cavity-containing objects. One of its favored applications is for assessing structural properties of bone. In this research, we perform a pilot study to visualize and characterize bone structure of a chicken bone thigh, as well as to delineate its cortical and trabecular bone regions. We utilize an In-Vitro μCT scanner Skyscan 1173 to acquire a three dimensional image data of a chicken bone thigh. The thigh was scanned using X-ray voltage of 45 kV and current of 150 μA. The reconstructed images have spatial resolution of 142.50 μm/pixel. Using image processing and analysis e.i segmentation by thresholding the gray values (which represent the pseudo density) and binarizing the images, we were able to visualize each part of the bone, i.e., the cortical and trabecular regions. Total volume of the bone is 4663.63 mm{sup 3}, and the surface area of the bone is 7913.42 mm{sup 2}. The volume of the cortical is approximately 1988.62 mm{sup 3} which is nearly 42.64% of the total bone volume. This pilot study has confirmed that the μCT is capable of quantifying 3D bone structural properties and defining its regions separately. For further development, these results can be improved for understanding the pathophysiology of bone abnormality, testing the efficacy of pharmaceutical intervention, or estimating bone biomechanical properties.

  13. Study of Anthropometric Measurements of the Anterior Ethmoidal Artery using Three-dimensional Scanning on 300 Patients

    Science.gov (United States)

    Bortoli, Vinicius Tomadon; Martins, Rafael Ferri; Negri, Krystal Calmeto

    2017-01-01

    Introduction The anterior ethmoidal artery (AEA) is one of the main arteries that supply both the nasal mucosa and the ethmoid sinuses. The AEA shows variability regarding its distance from adjacent structures. Several studies have developed techniques to identify the AEA. Objective This study aimed to compare the measurements from the AEA to the ethmoid bulla and to the frontal beak by using computed tomography of the face, while identifying their intraindividual and interindividual variations. Methods We analyzed 300 CT scans of the face performed at the CT scan Center at Hospital. The average age of subjects was 36 ± 15.1 years (range 4–84). Results We found that the average distance from the AEA to the ethmoid bulla was 17.2 ± 1.8 mm and the distance from the AEA to the frontal beak was 15.1 ± 2.2 mm. Regarding the average distance from the AEA to the frontal beak (AEA-frontal beak), there was a difference between the right and left sides, with the former being 0.4 mm higher on average than the latter. Among the age groups, there was a significant difference of distances between the AEA and the ethmoid bulla (AEA-ethmoid bulla), which were shorter in the ≤ 12 years group. There was a positive and significant correlation between both measurements analyzed, with low values (high) of AEA-ethmoid bulla distance corresponding to low values (high) of AEA-frontal beak distance. Conclusion The measurements obtained adds anatomical knowledge that can serve as a parameter in frontal and ethmoid sinus surgery. PMID:28382116

  14. CT liver volumetry using three-dimensional image data in living donor liver transplantation: Effects of slice thickness on volume calculation

    Science.gov (United States)

    Hori, Masatoshi; Suzuki, Kenji; Epstein, Mark L.; Baron, Richard L.

    2011-01-01

    The purpose was to evaluate a relationship between slice thickness and calculated volume on CT liver volumetry by comparing the results for images with various slice thicknesses including three-dimensional images. Twenty adult potential liver donors (12 men, 8 women; mean age, 39 years; range, 24–64) underwent CT with a 64-section multi-detector row CT scanner after intra-venous injection of contrast material. Four image sets with slice thicknesses of 0.625 mm, 2.5 mm, 5 mm, and 10 mm were used. First, a program developed in our laboratory for automated liver extraction was applied to CT images, and the liver boundary was obtained automatically. Then, an abdominal radiologist reviewed all images on which automatically extracted boundaries were superimposed, and edited the boundary on each slice to enhance the accuracy. Liver volumes were determined by counting of the voxels within the liver boundary. Mean whole liver volumes estimated with CT were 1322.5 cm3 on 0.625-mm, 1313.3 cm3 on 2.5-mm, 1310.3 cm3 on 5-mm, and 1268.2 cm3 on 10-mm images. Volumes calculated for three-dimensional (0.625-mm-thick) images were significantly larger than those for thicker images (Pvolumetry. If not, three-dimensional images could be essential. PMID:21850689

  15. Combination of three-dimensional laser scanning and digital photogrammetric shoot for fixing and measurement of architectural monuments

    OpenAIRE

    S.V. Tiurin; S.G. Tihonov

    2010-01-01

    Several variants of architectural monument fixing using photogrammetric method are considered: black-and-white and colour three-dimensional point models; black-and-white and colour orthophotomaps in format SPO; black-and-white and colour orthophotomaps in standard raster formats. For different aims authors recommend corresponding data formats.

  16. Uncertainty evaluation for three-dimensional scanning electron microscope reconstructions based on the stereo-pair technique

    DEFF Research Database (Denmark)

    Carli, Lorenzo; Genta, G; Cantatore, Angela

    2011-01-01

    3D-SEM is a method, based on the stereophotogrammetry technique, which obtains three-dimensional topographic reconstructions starting typically from two SEM images, called the stereo-pair. In this work, a theoretical uncertainty evaluation of the stereo-pair technique, according to GUM (Guide to ...

  17. New Statistical Method to Analyze Three-Dimensional Landmark Configurations Obtained with Cone-Beam CT: Basic Features and Clinical Application for Rapid Maxillary Expansion

    Energy Technology Data Exchange (ETDEWEB)

    Gamble, Jennifer; Lagravere, Manuel O.; Major, Paul W.; Heo, Giseon [University of Alberta, Edmonton (Canada)

    2012-03-15

    To describe a statistical method of three-dimensional landmark configuration data and apply it to an orthodontic data set comparing two types of rapid maxillary expansion (RME) treatments. Landmark configurations obtained from cone beam CT scans were used to represent patients in two types (please describe what were two types) of RME groups and a control group over four time points. A method using tools from persistent homology and dimensionality reduction is presented and used to identify variability between the subjects. The analysis was in agreement with previous results using conventional methods, which found significant differences between treatment groups and the control, but no distinction between the types of treatment. Additionally, it was found that second molar eruption varied considerably between the subjects, and this has not been evaluated in previous analyses. This method of analysis allows entire configurations to be considered as a whole, and does not require specific inter-landmark distances or angles to be selected. Sources of variability present themselves, without having to be individually sought after. This method is suggested as an additional tool for the analysis of landmark configuration data.

  18. Three-dimensional reconstructions of the orbital floor by volume-rendering of multidetector-row CT data

    International Nuclear Information System (INIS)

    Yoshikawa, Tetsuya; Miyajima, Akira; Fujita, Yuko; Yamada, Kazuo

    2011-01-01

    The advent of 3D-CT has made the evaluation of complicated facial fractures much easier than before. However, its use in injuries involving the orbital floor has been limited by the difficulty of visualizing the thin bony structures given artifacts caused by the partial volume effect. Nevertheless, high-technology machines such as multidetector-row CT (MDCT) and new-generation software have improved the quality of 3D imaging, and this paper describes a procedure for obtaining better visualization of the orbital floor using a MDCT scanner. Forty trauma cases were subject to MDCT: 13 with injury to the orbital floor, and 27 without. All scans were performed in the standard manner, at slice thicknesses of 0.5 mm. 3D-CT images were created overlooking the orbital floor including soft tissue to minimize the pseudo-foramen artifacts produced through volume rendering. Bone deficits, fracture lines, and grafted bone were visible in the 3D images, and visualization was supported by the ready creation of stereoscopic images from MDCT volume data. Measurement of the pseudo-foramen revealed approximately half the artifacts to be less than 5 mm in diameter, suggesting practicality of this method without subjecting the patient to undue increases in radiation exposure in the treatment of cases involving injury to the orbital floor. (author)

  19. Definition of the supraclavicular and infraclavicular nodes: implications for three-dimensional CT-based conformal radiation therapy.

    Science.gov (United States)

    Madu, C N; Quint, D J; Normolle, D P; Marsh, R B; Wang, E Y; Pierce, L J

    2001-11-01

    To delineate with computed tomography (CT) the anatomic regions containing the supraclavicular (SCV) and infraclavicular (IFV) nodal groups, to define the course of the brachial plexus, to estimate the actual radiation dose received by these regions in a series of patients treated in the traditional manner, and to compare these doses to those received with an optimized dosimetric technique. Twenty patients underwent contrast material-enhanced CT for the purpose of radiation therapy planning. CT scans were used to study the location of the SCV and IFV nodal regions by using outlining of readily identifiable anatomic structures that define the nodal groups. The brachial plexus was also outlined by using similar methods. Radiation therapy doses to the SCV and IFV were then estimated by using traditional dose calculations and optimized planning. A repeated measures analysis of covariance was used to compare the SCV and IFV depths and to compare the doses achieved with the traditional and optimized methods. Coverage by the 90% isodose surface was significantly decreased with traditional planning versus conformal planning as the depth to the SCV nodes increased (P correlation was found between brachial plexus depth and SCV depth up to 7 cm. Conformal optimized planning provided improved dosimetric coverage compared with standard techniques.

  20. A three-dimensional definition of nodal spaces on the basis of CT images showing enlarged nodes for pelvic radiotherapy

    International Nuclear Information System (INIS)

    Portaluri, Maurizio; Bambace, Santa; Perez, Celeste; Angone, Grazia

    2005-01-01

    Purpose: To demonstrate that margins of each pelvic chain may be derived by verifying the bony and soft tissue structures around abnormal nodes on computed tomography (CT) slices. Methods and Materials: Twenty consecutive patients (16 males, 4 females; mean age, 66 years; range, 43-80 years) with radiologic diagnosis of nodal involvement by histologically proved cervix carcinoma (two), rectum carcinoma (three), prostate carcinoma (four), lymphoma (five), penis carcinoma (one), corpus uteri carcinoma (one), bladder carcinoma (two), cutis tumor (one), and soft-tissue sarcoma (one) were retrospectively reviewed. One hundred CT scans showing 85 enlarged pelvic nodes were reviewed by two radiation oncologists (M.P., S.B.), and two radiologists (C.P., G.A.). Results: The more proximal structures to each enlarged node or group of nodes were thus recorded in a clockwise direction. Conclusion: According to their frequency and visibility, craniocaudal, anterior, lateral, posterior and medial margins of common iliac, external and internal iliac nodal chains, obturator and pudendal nodes, and deep and superficial inguinal nodes were derived from CT observations

  1. Trabecular bone strains around a dental implant and associated micromotions--a micro-CT-based three-dimensional finite element study.

    Science.gov (United States)

    Limbert, Georges; van Lierde, Carl; Muraru, O Luiza; Walboomers, X Frank; Frank, Milan; Hansson, Stig; Middleton, John; Jaecques, Siegfried

    2010-05-07

    The first objective of this computational study was to assess the strain magnitude and distribution within the three-dimensional (3D) trabecular bone structure around an osseointegrated dental implant loaded axially. The second objective was to investigate the relative micromotions between the implant and the surrounding bone. The work hypothesis adopted was that these virtual measurements would be a useful indicator of bone adaptation (resorption, homeostasis, formation). In order to reach these objectives, a microCT-based finite element model of an oral implant implanted into a Berkshire pig mandible was developed along with a robust software methodology. The finite element mesh of the 3D trabecular bone architecture was generated from the segmentation of microCT scans. The implant was meshed independently from its CAD file obtained from the manufacturer. The meshes of the implant and the bone sample were registered together in an integrated software environment. A series of non-linear contact finite element (FE) analyses considering an axial load applied to the top of the implant in combination with three sets of mechanical properties for the trabecular bone tissue was devised. Complex strain distribution patterns are reported and discussed. It was found that considering the Young's modulus of the trabecular bone tissue to be 5, 10 and 15GPa resulted in maximum peri-implant bone microstrains of about 3000, 2100 and 1400. These results indicate that, for the three sets of mechanical properties considered, the magnitude of maximum strain lies within an homeostatic range known to be sufficient to maintain/form bone. The corresponding micro-motions of the implant with respect to the bone microstructure were shown to be sufficiently low to prevent fibrous tissue formation and to favour long-term osseointegration. Copyright 2010 Elsevier Ltd. All rights reserved.

  2. Influence of heart rhythm, breathing and arm position during computed tomography scanning on the registration accuracy of electro anatomical map (EAM) images, left atrium three-dimensional computed tomography angiography images, and fluoroscopy time during ablation to treat atrial fibrillation

    International Nuclear Information System (INIS)

    Chono, Taiki; Shimoshige, Shinya; Yoshikawa, Kenta; Mizonobe, Kazuhusa; Ogura, Keishi

    2013-01-01

    In CARTOMERGE for treatment of atrial fibrillation (AF) by ablation, by integrating electro anatomical map (EAM) and left atrium three-dimensional computed tomography angiography (3D-CTA) images, identification of the ablation points is simplified and the procedure can be made carried out more rapidly. However, the influence that heart rhythm, breathing and arm position during CT scanning have on registration accuracy and fluoroscopy time is not clear. To clarify the influence on registration accuracy and fluoroscopy time of heart rhythm, breathing and arm position during CT scanning. The patients were CT-scanned during both sinus rhythm (SR) and AF in each study subject. We evaluated the registration accuracy of images reconstructed between the cardiac cycle and assessed the registration accuracy and fluoroscopy time of images obtained during inspiratory breath-hold, expiratory breath-hold and up and down position of the arm. Although the registration accuracy of the EAM image and left atrium 3D-CTA image showed a significant difference during SR, no significant difference was seen during AF. Expiratory breath-hold and down position of the arm resulted in the highest registration accuracy and the shortest fluoroscopy time. However, arm position had no significant effect on registration accuracy. Heart rhythm and breathing during CT scanning have a significant effect on the registration accuracy of EAM images, left atrium 3D-CTA images, and fluoroscopy time. (author)

  3. Imaging the Aqueous Humor Outflow Pathway in Human Eyes by Three-dimensional Micro-computed Tomography (3D micro-CT)

    Energy Technology Data Exchange (ETDEWEB)

    C Hann; M Bentley; A Vercnocke; E Ritman; M Fautsch

    2011-12-31

    The site of outflow resistance leading to elevated intraocular pressure in primary open-angle glaucoma is believed to be located in the region of Schlemm's canal inner wall endothelium, its basement membrane and the adjacent juxtacanalicular tissue. Evidence also suggests collector channels and intrascleral vessels may have a role in intraocular pressure in both normal and glaucoma eyes. Traditional imaging modalities limit the ability to view both proximal and distal portions of the trabecular outflow pathway as a single unit. In this study, we examined the effectiveness of three-dimensional micro-computed tomography (3D micro-CT) as a potential method to view the trabecular outflow pathway. Two normal human eyes were used: one immersion fixed in 4% paraformaldehyde and one with anterior chamber perfusion at 10 mmHg followed by perfusion fixation in 4% paraformaldehyde/2% glutaraldehyde. Both eyes were postfixed in 1% osmium tetroxide and scanned with 3D micro-CT at 2 {mu}m or 5 {mu}m voxel resolution. In the immersion fixed eye, 24 collector channels were identified with an average orifice size of 27.5 {+-} 5 {mu}m. In comparison, the perfusion fixed eye had 29 collector channels with a mean orifice size of 40.5 {+-} 13 {mu}m. Collector channels were not evenly dispersed around the circumference of the eye. There was no significant difference in the length of Schlemm's canal in the immersed versus the perfused eye (33.2 versus 35.1 mm). Structures, locations and size measurements identified by 3D micro-CT were confirmed by correlative light microscopy. These findings confirm 3D micro-CT can be used effectively for the non-invasive examination of the trabecular meshwork, Schlemm's canal, collector channels and intrascleral vasculature that comprise the distal outflow pathway. This imaging modality will be useful for non-invasive study of the role of the trabecular outflow pathway as a whole unit.

  4. Colour-coded three-dimensional reconstruction from spiral CT data sets: Improvement from the physical point of view

    International Nuclear Information System (INIS)

    Wunderlich, A.P.; Lenz, M.; Kirsten, R.; Gerhardt, P.

    1993-01-01

    This paper demonstrates the possibility of improving the spatial depth impression of colour-coded three-dimensional reconstructions by modulation of colour saturation. Patients were observed with spiral computed tomography (slice thickness 10 mm, table feed 10 mm/s, reconstruction of overlapping axial images at 2 mm increment). Interesting anatomical and pathological objects (vessels, organs, tumours, metastases) were segmented, colour-coded, and reconstructed three-dimensionally. Spatial depth impression of the coloured objects could be improved by modulating not only the brightness, but also the colour saturation. (orig.) [de

  5. Pre-operative CT angiography and three-dimensional image post processing for deep inferior epigastric perforator flap breast reconstructive surgery.

    Science.gov (United States)

    Lam, D L; Mitsumori, L M; Neligan, P C; Warren, B H; Shuman, W P; Dubinsky, T J

    2012-12-01

    Autologous breast reconstructive surgery with deep inferior epigastric artery (DIEA) perforator flaps has become the mainstay for breast reconstructive surgery. CT angiography and three-dimensional image post processing can depict the number, size, course and location of the DIEA perforating arteries for the pre-operative selection of the best artery to use for the tissue flap. Knowledge of the location and selection of the optimal perforating artery shortens operative times and decreases patient morbidity.

  6. Three-dimensional nanofabrication by electron-beam-induced deposition using 200-keV electrons in scanning transmission electron microscope

    International Nuclear Information System (INIS)

    Liu, Z.Q.; Mitsuishi, K.; Furuya, K.

    2005-01-01

    Attempts were made to fabricate three-dimensional nanostructures on and out of a substrate by electron-beam-induced deposition in a 200-kV scanning transmission electron microscope. Structures with parallel wires over the substrate surface were difficult to fabricate due to the direct deposition of wires on both top and bottom surfaces of the substrate. Within the penetration depth of the incident electron beam, nanotweezers were fabricated by moving the electron beam beyond different substrate layers. Combining the deposition of self-supporting wires and self-standing tips, complicated three-dimensional doll-like, flag-like, and gate-like nanostructures that extend out of the substrate were successfully fabricated with one-step or multi-step scans of the electron beam. Effects of coarsening, nucleation, and distortion during electron-beam-induced deposition are discussed. (orig.)

  7. Three-dimensional image technology in forensic anthropology: Assessing the validity of biological profiles derived from CT-3D images of the skeleton

    Science.gov (United States)

    Garcia de Leon Valenzuela, Maria Julia

    This project explores the reliability of building a biological profile for an unknown individual based on three-dimensional (3D) images of the individual's skeleton. 3D imaging technology has been widely researched for medical and engineering applications, and it is increasingly being used as a tool for anthropological inquiry. While the question of whether a biological profile can be derived from 3D images of a skeleton with the same accuracy as achieved when using dry bones has been explored, bigger sample sizes, a standardized scanning protocol and more interobserver error data are needed before 3D methods can become widely and confidently used in forensic anthropology. 3D images of Computed Tomography (CT) scans were obtained from 130 innominate bones from Boston University's skeletal collection (School of Medicine). For each bone, both 3D images and original bones were assessed using the Phenice and Suchey-Brooks methods. Statistical analysis was used to determine the agreement between 3D image assessment versus traditional assessment. A pool of six individuals with varying experience in the field of forensic anthropology scored a subsample (n = 20) to explore interobserver error. While a high agreement was found for age and sex estimation for specimens scored by the author, the interobserver study shows that observers found it difficult to apply standard methods to 3D images. Higher levels of experience did not result in higher agreement between observers, as would be expected. Thus, a need for training in 3D visualization before applying anthropological methods to 3D bones is suggested. Future research should explore interobserver error using a larger sample size in order to test the hypothesis that training in 3D visualization will result in a higher agreement between scores. The need for the development of a standard scanning protocol focusing on the optimization of 3D image resolution is highlighted. Applications for this research include the possibility

  8. Experimental validation of a newly designed 6 degrees of freedom scanning laser head: Application to three-dimensional beam structure

    International Nuclear Information System (INIS)

    Di Maio, D.; Copertaro, E.

    2013-01-01

    A new scanning laser head is designed to use single Laser Doppler Vibrometer (LDV) for performing measurements up to 6 degrees of freedom (DOF) at a target. The scanning head is supported by a rotating hollow shaft, which allows the laser beam to travel up to the scanning head from an opposite direction where an LDV is set up. The scanning head is made of a set of two mirrors, which deflects the laser beam with an angle so that the rotation of the scanning head produces a conical scan. When measurements are performed at the focal point of the conical scan then three translational vibration components can be measured, otherwise the very small circle scan, before and after the focal point, can measure up to 6 degrees of freedom, including three translations and three rotations. This paper presents the 6DOF scanning head and the measurements of 3D operational deflection shapes of a test structure

  9. [Measurement of the frontal and prefrontal lobe volumes in children with malnutrition by three dimensional magnetic resonance imaging scan].

    Science.gov (United States)

    Kanemura, Hideaki; Aihara, Masao; Nakazawa, Shinpei

    2002-09-01

    To evaluate the effects of malnutrition in early life on the growth of the frontal and prefrontal lobes, we quantitatively measured the volumes of the frontal and prefrontal lobes by three dimensional (3-D) MRI in three children (1 year 2 months to 2 years 5 months) with malnutrition. The 3-D MRI data were acquired by the fast spoiled gradient recalled (SPGR) sequence using a 1.5T MR imager. The frontal and prefrontal lobe volumes were measured by the volume measurement function of the Workstation. The data obtained were compared with those of 16 normal subjects (13 children aged 5 months to 14 years, and 3 adults aged 27 to 39 years). The volumes of the frontal and prefrontal lobes in the subjects were smaller compared with age matched controls. The results suggest that malnutrition in early life affects the growth of the frontal and prefrontal lobes.

  10. Automatic prostate localization on cone-beam CT scans for high precision image-guided radiotherapy

    NARCIS (Netherlands)

    Smitsmans, Monique H. P.; de Bois, Josien; Sonke, Jan-Jakob; Betgen, Anja; Zijp, Lambert J.; Jaffray, David A.; Lebesque, Joos V.; van Herk, Marcel

    2005-01-01

    PURPOSE: Previously, we developed an automatic three-dimensional gray-value registration (GR) method for fast prostate localization that could be used during online or offline image-guided radiotherapy. The method was tested on conventional computed tomography (CT) scans. In this study, the

  11. Uncertainty evaluation for three-dimensional scanning electron microscope reconstructions based on the stereo-pair technique

    International Nuclear Information System (INIS)

    Carli, L; Cantatore, A; De Chiffre, L; Genta, G; Barbato, G; Levi, R

    2011-01-01

    3D-SEM is a method, based on the stereophotogrammetry technique, which obtains three-dimensional topographic reconstructions starting typically from two SEM images, called the stereo-pair. In this work, a theoretical uncertainty evaluation of the stereo-pair technique, according to GUM (Guide to the Expression of Uncertainty in Measurement), was carried out, considering 3D-SEM reconstructions of a wire gauge with a reference diameter of 250 µm. Starting from the more commonly used tilting strategy, one based on the item rotation inside the SEM chamber was also adopted. The latter enables multiple-view reconstructions of the cylindrical item under consideration. Uncertainty evaluation was performed starting from a modified version of the Piazzesi equation, enabling the calculation of the z-coordinate from a given stereo-pair. The metrological characteristics of each input variable have been taken into account and a SEM stage calibration has been performed. Uncertainty tables for the cases of tilt and rotation were then produced, leading to the calculation of expanded uncertainty. For the case of rotation, the largest uncertainty contribution resulted to be the rotational angle; however, for the case of tilt it resulted to be the pixel size. A relative expanded uncertainty equal to 5% and 4% was obtained for the case of rotation and tilt, respectively

  12. Image Quality and Radiation Dose of CT Coronary Angiography with Automatic Tube Current Modulation and Strong Adaptive Iterative Dose Reduction Three-Dimensional (AIDR3D.

    Directory of Open Access Journals (Sweden)

    Hesong Shen

    Full Text Available To investigate image quality and radiation dose of CT coronary angiography (CTCA scanned using automatic tube current modulation (ATCM and reconstructed by strong adaptive iterative dose reduction three-dimensional (AIDR3D.Eighty-four consecutive CTCA patients were collected for the study. All patients were scanned using ATCM and reconstructed with strong AIDR3D, standard AIDR3D and filtered back-projection (FBP respectively. Two radiologists who were blinded to the patients' clinical data and reconstruction methods evaluated image quality. Quantitative image quality evaluation included image noise, signal-to-noise ratio (SNR, and contrast-to-noise ratio (CNR. To evaluate image quality qualitatively, coronary artery is classified into 15 segments based on the modified guidelines of the American Heart Association. Qualitative image quality was evaluated using a 4-point scale. Radiation dose was calculated based on dose-length product.Compared with standard AIDR3D, strong AIDR3D had lower image noise, higher SNR and CNR, their differences were all statistically significant (P<0.05; compared with FBP, strong AIDR3D decreased image noise by 46.1%, increased SNR by 84.7%, and improved CNR by 82.2%, their differences were all statistically significant (P<0.05 or 0.001. Segments with diagnostic image quality for strong AIDR3D were 336 (100.0%, 486 (96.4%, and 394 (93.8% in proximal, middle, and distal part respectively; whereas those for standard AIDR3D were 332 (98.8%, 472 (93.7%, 378 (90.0%, respectively; those for FBP were 217 (64.6%, 173 (34.3%, 114 (27.1%, respectively; total segments with diagnostic image quality in strong AIDR3D (1216, 96.5% were higher than those of standard AIDR3D (1182, 93.8% and FBP (504, 40.0%; the differences between strong AIDR3D and standard AIDR3D, strong AIDR3D and FBP were all statistically significant (P<0.05 or 0.001. The mean effective radiation dose was (2.55±1.21 mSv.Compared with standard AIDR3D and FBP, CTCA

  13. Three-dimensional evaluation of the repeatability of scans of stone models and impressions using a blue LED scanner.

    Science.gov (United States)

    Jeon, Jin-Hun; Jung, Il-Do; Kim, Ji-Hwan; Kim, Hae-Young; Kim, Woong-Chul

    2015-01-01

    In this study, we evaluated the repeatability of scans of stone models and impressions of abutment teeth using a blue LED scanner and compared the findings between different abutment teeth types. For the stone models as well as impression of the canines, premolars, and molars, we generated 10 color-difference-maps and reports for each tooth type (n=10 per tooth type). One-way analysis of variance (ANOVA) and independent t-tests were performed to evaluate the repeatability of scans of the stone models and impressions obtained from a blue LED scanner. Our results indicate a high repeatability of scans of stone models and impressions of abutment teeth using the blue LED scanner and suggest a possible clinical advantage for scanning impressions of different abutment teeth types.

  14. Preoperative Prediction of Ki-67 Labeling Index By Three-dimensional CT Image Parameters for Differential Diagnosis Of Ground-Glass Opacity (GGO.

    Directory of Open Access Journals (Sweden)

    Mingzheng Peng

    Full Text Available The aim of this study was to predict Ki-67 labeling index (LI preoperatively by three-dimensional (3D CT image parameters for pathologic assessment of GGO nodules. Diameter, total volume (TV, the maximum CT number (MAX, average CT number (AVG and standard deviation of CT number within the whole GGO nodule (STD were measured by 3D CT workstation. By detection of immunohistochemistry and Image Software Pro Plus 6.0, different Ki-67 LI were measured and statistically analyzed among preinvasive adenocarcinoma (PIA, minimally invasive adenocarcinoma (MIA and invasive adenocarcinoma (IAC. Receiver operating characteristic (ROC curve, Spearman correlation analysis and multiple linear regression analysis with cross-validation were performed to further research a quantitative correlation between Ki-67 labeling index and radiological parameters. Diameter, TV, MAX, AVG and STD increased along with PIA, MIA and IAC significantly and consecutively. In the multiple linear regression model by a stepwise way, we obtained an equation: prediction of Ki-67 LI=0.022*STD+0.001* TV+2.137 (R=0.595, R's square=0.354, p<0.001, which can predict Ki-67 LI as a proliferative marker preoperatively. Diameter, TV, MAX, AVG and STD could discriminate pathologic categories of GGO nodules significantly. Ki-67 LI of early lung adenocarcinoma presenting GGO can be predicted by radiologic parameters based on 3D CT for differential diagnosis.

  15. Developing a methodology for three-dimensional correlation of PET-CT images and whole-mount histopathology in non-small-cell lung cancer.

    Science.gov (United States)

    Dahele, M; Hwang, D; Peressotti, C; Sun, L; Kusano, M; Okhai, S; Darling, G; Yaffe, M; Caldwell, C; Mah, K; Hornby, J; Ehrlich, L; Raphael, S; Tsao, M; Behzadi, A; Weigensberg, C; Ung, Y C

    2008-10-01

    Understanding the three-dimensional (3D) volumetric relationship between imaging and functional or histopathologic heterogeneity of tumours is a key concept in the development of image-guided radiotherapy. Our aim was to develop a methodologic framework to enable the reconstruction of resected lung specimens containing non-small-cell lung cancer (NSCLC), to register the result in 3D with diagnostic imaging, and to import the reconstruction into a radiation treatment planning system. We recruited 12 patients for an investigation of radiology-pathology correlation (RPC) in nsclc. Before resection, imaging by positron emission tomography (PET) or computed tomography (CT) was obtained. Resected specimens were formalin-fixed for 1-24 hours before sectioning at 3-mm to 10-mm intervals. To try to retain the original shape, we embedded the specimens in agar before sectioning. Consecutive sections were laid out for photography and manually adjusted to maintain shape. Following embedding, the tissue blocks underwent whole-mount sectioning (4-mum sections) and staining with hematoxylin and eosin. Large histopathology slides were used to whole-mount entire sections for digitization. The correct sequence was maintained to assist in subsequent reconstruction. Using Photoshop (Adobe Systems Incorporated, San Jose, CA, U.S.A.), contours were placed on the photographic images to represent the external borders of the section and the extent of macroscopic disease. Sections were stacked in sequence and manually oriented in Photoshop. The macroscopic tumour contours were then transferred to MATLAB (The Mathworks, Natick, MA, U.S.A.) and stacked, producing 3D surface renderings of the resected specimen and embedded gross tumour. To evaluate the microscopic extent of disease, customized "tile-based" and commercial confocal panoramic laser scanning (TISSUEscope: Biomedical Photometrics, Waterloo, ON) systems were used to generate digital images of whole-mount histopathology sections

  16. A walk by the river: three-dimensional reconstruction of surface sedimentology and topography using wearable laser scanning

    Science.gov (United States)

    Williams, R.; Lamy, M. L.; Stott, E.; Maniatis, G.

    2017-12-01

    In the last two decades, quantification of fluvial topography has been transformed by a number of geomatics technologies that have enabled the acquisition of data with unprecedented spatial resolution. Hyperscale surveys with spatial extents of <1 km2 have been widely demonstrated, by means of Terrestrial Laser Scanning (TLS) and Structure-from-Motion (SfM) photogrammetry. Recent advances in the development and integration of GNSS, IMU, lightweight laser scanning and SLAM technologies are now resulting in the emergence of wearable, mobile laser scanning systems that have the potential to increase data acquisition and processing rates by 1-2 orders of magnitude compared to TLS/SfM, and thus challenge the recent dominance of these two geomatics technologies. In this study we describe the methods and results of a comparison between a wearable laser scanning survey, using a Leica Pegasus Backpack, and a multi-station static TLS survey, using a Riegl VZ-1000 scanner. The evaluation is undertaken on a 600 m long reach of the braided River Feshie, Scotland, using data acquired in June 2017. Comparison between the DEMs produced from static and mobile laser scanning, across non-vegetated areas, revealed a Mean Error (ME) of -0.002 m and a Standard Deviation Error (SDE) of 0.109 m. Comparison to 100 independent check point resulted in a similar ME and SDE for static (ME = 0.061m; SDE = 0.030 m) and mobile (ME = 0.044 m; SDE = 0.029 m) laser scanning. Empirical relationships between sub-metre topographic variability and median sediment grain size (10-100 mm), across 14 grid-by-number samples, were similar and demonstrate that surface roughness from wearable laser scanning can be used to derive reach-scale maps of median grain size. These results demonstrate that wearable laser scanning generates hyperscale topographic models that are comparable in quality to more time-consuming multi-station TLS setups. Wearable laser scanning is likely to be commonly adopted for fluvial

  17. Investigation on the traceability of three dimensional scanning electron microscope measurements based on the stereo-pair technique

    DEFF Research Database (Denmark)

    Bariani, Paolo; De Chiffre, Leonardo; Hansen, Hans Nørgaard

    2005-01-01

    An investigation was carried out concerning the traceability of dimensional measurements performed with the scanning electron microscope (SEM) using reconstruction of surface topography through stereo-photogrammetry. A theoretical description of the effects that the main instrumental variables...... with the scanning electron microscope (SEM) using reconstruction of surface topography through stereo-photogrammetry. A theoretical description of the effects that the main instrumental variables and measurement parameters have on the reconstruction accuracy of any point on the surface of the object being imaged......-dimensional topography of the type C roughness standards showed good agreement with the nominal profile wavelength values. An investigation was carried out concerning the traceability of dimensional measurements performed with the scanning electron microscope (SEM) using reconstruction of surface topography through...

  18. Investigation of the effects of type of crusher on coarse aggregates shape properties using three-dimensional Laser Scanning Technique

    CSIR Research Space (South Africa)

    Komba, Julius J

    2016-07-01

    Full Text Available of quartzite aggregates crushed by using four different types of crushers were investigated. The results have demonstrated the extent to which the aggregate shape indices computed using laser scan results can be used to distinguish aggregate by-product from...

  19. Impact of the planning CT scan time on the reflection of the lung tumor motion

    International Nuclear Information System (INIS)

    Kim, Su San; Choi, Eun Kyung; Yi, Byong Yong; Ha, Sung Whan

    2004-01-01

    To evaluate the reflection of tumor motion according to the planning CT scan time. A model of N-shape, which moved along the longitudinal axis during the ventilation caused by a mechanical ventilator, was produced. The model was scanned by planning CT, while setting the relative CT scan time (T; CT scan time/ventilatory period) to 0.33, 0.50, 0.67, 0.75, 1.00, 1.33 T, and 1.53 T. In addition, three patients with non-small cell lung cancer who received stereotactic radiosurgery in the Department of Radiation Oncology, Asan Medical Center from 03/19/2002 to 05/21/2002 were scanned. Slow (IQ Premier, Picker, scan time 2.0 seconds per slice) and fast CT scans (Light Speed, GE Medical System, with a scan time of 0.8 second per slice) were performed for each patient. The magnitude of reflected movement of the N-shaped model was evaluated by measuring the transverse length, which reflected the movement of the declined bar of the model at each slice. For patients' scans, all CT data sets were registered using a stereotactic body frame scale with the gross tumor volumes delineated in one CT image set. The volume and three-dimensional diameter of the gross tumor volume were measured and analyzed between the slow and fast CT scans. The reflection degree of longitudinal movement of the model increased in proportion to the relative CT scan times below 1.00 T, but remained constant above 1.00 T. Assuming the mean value of scanned transverse lengths with CT scan time 1.00 T to be 100%, CT scans with scan times of 0.33, 0.50, 0.67, and 0.75 T missed the tumor motion by 30, 27, 20, and 7.0% respectively. Slow (scan time 2.0 sec) and Fast (scan time 0.8 sec) CT scans of three patients with longitudinal movement of 3, 5, and 10 mm measured by fluoroscopy revealed the increases in the diameter along the longitudinal axis increased by 6.3, 17, and 23% in the slow CT scans. As the relative CT scan time increased, the reflection of the respiratory tumor movement on planning CT also

  20. Advanced imaging of the musculoskeletal system: Standard, three-dimensional, and contrast-enhanced CT and MR imaging, and quantitative bone densitometry

    International Nuclear Information System (INIS)

    Resnick, D.; Sartoris, D.J.

    1987-01-01

    This course reviews the application of advanced imaging techniques to a broad spectrum of musculoskeletal disorders. The indications for and utility of standard CT in both the axial and the appendicular skeleton is explored. The combined use of CT with air and contrast arthrography at sites including the hip, knee, and shoulder is discussed. A summary of the proved and potential applications of MR imaging in osseous, articular, bone marrow, and soft-tissue disorders is provided. The utility of intraarticular contrast agents in enhancing the diagnostic capabilities of MR imaging for disorders of hyaline cartilage and and fibrocartilage is demonstrated. The advantages of multiplanar reformation and three-dimensional image reconstruction of cross-sectional imaging data are described in conjunction with the fundamental technological principles of these strategies. Accepted methods as well as investigative techniques for the diagnosis and follow-up of metabolic bone disease are contrasted with regard to relative indications, advantages, and limitations

  1. The advantage of the three dimensional computed tomographic (3 D-CT for ensuring accurate bone incision in sagittal split ramus osteotomy

    Directory of Open Access Journals (Sweden)

    Coen Pramono D

    2005-03-01

    Full Text Available Functional and aesthetic dysgnathia surgery requires accurate pre-surgical planning, including the surgical technique to be used related with the difference of anatomical structures amongst individuals. Programs that simulate the surgery become increasingly important. This can be mediated by using a surgical model, conventional x-rays as panoramic, cephalometric projections and another sophisticated method such as a three dimensional computed tomography (3 D-CT. A patient who had undergone double jaw surgeries with difficult anatomical landmarks was presented. In this case the mandible foramens were seen highly relatively related to the sigmoid notches. Therefore, ensuring the bone incisions in sagittal split was presumed to be difficult. A 3D-CT was made and considered to be very helpful in supporting the pre-operative diagnostic.

  2. Development of a dynamic CT system for neutron radiography and consecutive visualization of three-dimensional water behavior in a PEFC stack

    International Nuclear Information System (INIS)

    Murakawa, Hideki; Hashimoto, Michinori; Sugimoto, Katsumi; Asano, Hitoshi; Takenaka, Nobuyuki; Mochiki, Koh-ichi; Yasuda, Ryo

    2011-01-01

    A dynamic CT system was developed for visualization of consecutive three-dimensional water behavior in a PEFC stack for neutron radiography. The system is composed of a neutron image intensifier and a C-MOS high speed video camera. An operating stack with three cells based on the Japan Automobile Research Institute standard was visualized using the neutron radiography system at a research reactor JRR-3 in Japan Atomic Energy Agency. The dynamic water behavior in channels in the operating PEFC stack was clearly visualized every 15 seconds by using the system. The water amount in each cell was evaluated by the CT reconstructed images. It was shown that a cell voltage decreased gradually when the water increased and increased rapidly when the water was evacuated. It was estimated that the power generation stopped when the channel of a cell was partly filled with the water because the air supply was blocked to a cell in the stack. (author)

  3. Accuracy of cancellous bone volume fraction measured by micro-CT scanning

    DEFF Research Database (Denmark)

    Ding, Ming; Odgaard, A; Hvid, I

    1999-01-01

    Volume fraction, the single most important parameter in describing trabecular microstructure, can easily be calculated from three-dimensional reconstructions of micro-CT images. This study sought to quantify the accuracy of this measurement. One hundred and sixty human cancellous bone specimens...... which covered a large range of volume fraction (9.8-39.8%) were produced. The specimens were micro-CT scanned, and the volume fraction based on Archimedes' principle was determined as a reference. After scanning, all micro-CT data were segmented using individual thresholds determined by the scanner...

  4. Single scan femtosecond laser transverse writing of depressed cladding waveguides enabled by three-dimensional focal field engineering.

    Science.gov (United States)

    Zhang, Qian; Yang, Dong; Qi, Jia; Cheng, Ya; Gong, Qihuang; Li, Yan

    2017-06-12

    We report single scan transverse writing of depressed cladding waveguides inside ZBLAN glass with the longitudinally oriented annular ring-shaped focal intensity distribution of the femtosecond laser. The entire region of depressed cladding at the cross section, where a negative change of refraction index is induced, can be modified simultaneously with the ring-shaped focal intensity profile. The fabricated waveguides exhibit good single guided mode.

  5. Direct observation for atomically flat and ordered vertical {111} side-surfaces on three-dimensionally figured Si(110) substrate using scanning tunneling microscopy

    Science.gov (United States)

    Yang, Haoyu; Hattori, Azusa N.; Ohata, Akinori; Takemoto, Shohei; Hattori, Ken; Daimon, Hiroshi; Tanaka, Hidekazu

    2017-11-01

    A three-dimensional Si{111} vertical side-surface structure on a Si(110) wafer was fabricated by reactive ion etching (RIE) followed by wet-etching and flash-annealing treatments. The side-surface was studied with scanning tunneling microscopy (STM) in atomic scale for the first time, in addition to atomic force microscopy (AFM), scanning electron microscopy (SEM), and low-energy electron diffraction (LEED). AFM and SEM showed flat and smooth vertical side-surfaces without scallops, and STM proved the realization of an atomically-flat 7 × 7-reconstructed structure, under optimized RIE and wet-etching conditions. STM also showed that a step-bunching occurred on the produced {111} side-surface corresponding to a reversely taped side-surface with a tilt angle of a few degrees, but did not show disordered structures. Characteristic LEED patterns from both side- and top-reconstructed surfaces were also demonstrated.

  6. Microsurgical management of cerebral aneurysms based in CT angiography with three-dimensional reconstruction (3D-CTA) and without preoperative cerebral angiography

    International Nuclear Information System (INIS)

    Gonzalez-Darder, J.M.; Pesudo-Martinez, J.V.; Feliu-Tatay, R.A.

    2001-01-01

    Objective. To study the possibilities of the microsurgical management of ruptured intracranial aneurysms with the sole preoperative information provided by computed tomography angiography with three-dimensional reconstruction (3D-CTA). Methods. Patients were studied with 3D-CTA after diagnosis of subarachnoid hemorrhage. If the study had an adequate quality and revealed an aneurysm congruent with the clinical findings or neurological examination and/or with the location of the bleeding on computed tomography (CT) scan an early microsurgical clipping of the lesion was done. When the quality of the 3D-CTA study was not adequate or the quality being adequate displayed no lesions or the findings were not accurate enough to warrant direct microsurgical treatment, the patient was studied with cerebral digital substraction (DS) angiography. A total of 44 consecutive patients harboring a total of 47 intracranial aneurysms diagnosed by 3D-CTA and without preoperative DS angiography were submitted to microsurgical clipping and included in the study. Results. The overall mortality was 15.9 % and the favorable results evaluated 6 months after discharge by means of the Glasgow outcome scale reached 70.4 %. All lesions were successfully clipped. Surgery was done a mean of 4.1 days after the admission bleeding. A total of four microlesions undiagnosed by 3D-CTA were found at surgery and clipped. Postoperative DS angiography and necropsy findings were also used as control of the 3D-CTA findings but no additional information was provided excepting the finding in DS angiography of an asymptomatic intracavemous aneurysm. Therefore the sensitivity of the 3D-CTA for diagnosis of symtomatic aneurysms was 100 % and the overall sensitivity 90.4 %. Conclusions. We have reached similar results in patients operated on with or without preoperative angiography. 3D-CTA provides very valuable anatomical information, which has an additional value in the microsurgical treatment of aneurysms of the

  7. Vascular anatomy of the liver and porta hepatis with dynamic CT scan

    International Nuclear Information System (INIS)

    Hiramatsu, Yoshihiro; Wada, Mitsuyoshi; Nakajima, Teiichi; Tonooka, Reiko; Matsumoto, Kunihiko

    1983-01-01

    Vascular anatomy of the liver and porta heaptis demonstrated by dynamic CT scan was studied Identification of the individual vessels was sometimes difficult due to slight differencies in respiratory depths among the scans. Limitation in the number of slices also made the evalution of the vascular anatomy difficult. Angiography was therefore utilized for comparison in identifying the vessels. Dynamic CT scan was proved to be usefull in demonstrating the anteroposterior relationship of the vessels and surrounding structures, which is difficult with convetional angiography without multiple projections. Three dimensional understanding of the vessels was then possible with dynamic CT scan and angiography. When combined with recently advancing digital subtraction angiography, dynamic CT scan might reduce the necessity for conventional angiography with Seldinger's technique. (author)

  8. Automatic Mapping of Forest Stands Based on Three-Dimensional Point Clouds Derived from Terrestrial Laser-Scanning

    Directory of Open Access Journals (Sweden)

    Tim Ritter

    2017-07-01

    Full Text Available Mapping of exact tree positions can be regarded as a crucial task of field work associated with forest monitoring, especially on intensive research plots. We propose a two-stage density clustering approach for the automatic mapping of tree positions, and an algorithm for automatic tree diameter estimates based on terrestrial laser-scanning (TLS point cloud data sampled under limited sighting conditions. We show that our novel approach is able to detect tree positions in a mixed and vertically structured stand with an overall accuracy of 91.6%, and with omission- and commission error of only 5.7% and 2.7% respectively. Moreover, we were able to reproduce the stand’s diameter in breast height (DBH distribution, and to estimate single trees DBH with a mean average deviation of ±2.90 cm compared with tape measurements as reference.

  9. Dental image replacement on cone beam computed tomography with three-dimensional optical scanning of a dental cast, occlusal bite, or bite tray impression.

    Science.gov (United States)

    Kang, S-H; Lee, J-W; Lim, S-H; Kim, Y-H; Kim, M-K

    2014-10-01

    The goal of the present study was to compare the accuracy of dental image replacement on a cone beam computed tomography (CBCT) image using digital image data from three-dimensional (3D) optical scanning of a dental cast, occlusal bite, and bite tray impression. A Bracket Typodont dental model was used. CBCT of the dental model was performed and the data were converted to stereolithography (STL) format. Three experimental materials, a dental cast, occlusal bite, and bite tray impression, were optically scanned in 3D. STL files converted from the CBCT of the Typodont model and the 3D optical-scanned STL files of the study materials were image-registered. The error range of each methodology was measured and compared with a 3D optical scan of the Typodont. For the three materials, the smallest error observed was 0.099±0.114mm (mean error±standard deviation) for registering the 3D optical scan image of the dental cast onto the CBCT dental image. Although producing a dental cast can be laborious, the study results indicate that it is the preferred method. In addition, an occlusal bite is recommended when bite impression materials are used. Copyright © 2014 International Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.

  10. High-speed scanning stroboscopic fringe-pattern projection technology for three-dimensional shape precision measurement.

    Science.gov (United States)

    Yang, Guowei; Sun, Changku; Wang, Peng; Xu, Yixin

    2014-01-10

    A high-speed scanning stroboscopic fringe-pattern projection system is designed. A high-speed rotating polygon mirror and a line-structured laser cooperate to produce stable and unambiguous stroboscopic fringe patterns. The system combines the rapidity of the grating projection with the high accuracy of the line-structured laser light source. The fringe patterns have fast frame rate, great density, high precision, and high brightness, with convenience and accuracy in adjusting brightness, frequency, linewidth, and the amount of phase shift. The characteristics and the stability of this system are verified by experiments. Experimental results show that the finest linewidth can reach 40 μm and that the minimum fringe cycle is 80 μm. Circuit modulation makes the light source system flexibly adjustable, easy to control in real time, and convenient to project various fringe patterns. Combined with different light intensity adjustment algorithms and 3D computation models, the 3D topography with high accuracy can be obtained for objects measured under different environments or objects with different sizes, morphologies, and optical properties. The proposed system shows a broad application prospect for fast 3D shape precision measurements, particularly in the industrial field of 3D online detection for precision devices.

  11. Three-dimensional reconstruction and visualization system for medical images

    International Nuclear Information System (INIS)

    Preston, D.F.; Batnitzky, S.; Kyo Rak Lee; Cook, P.N.; Cook, L.T.; Dwyer, S.J.

    1982-01-01

    A three-dimensional reconstruction and visualization system could be of significant advantage in medical application such as neurosurgery and radiation treatment planning. The reconstructed anatomic structures from CT head scans could be used in a head stereotactic system to help plan the surgical procedure and the radiation treatment for a brain lesion. Also, the use of three-dimensional reconstruction algorithm provides for quantitative measures such as volume and surface area estimation of the anatomic features. This aspect of the three-dimensional reconstruction system may be used to monitor the progress or staging of a disease and the effects of patient treatment. Two cases are presented to illustrate the three-dimensional surface reconstruction and visualization system

  12. Tree crown structural characterization: A study using terrestrial laser scanning and three-dimensional radiative transfer modeling

    Science.gov (United States)

    Moorthy, Inian

    Spectroscopic observational data for vegetated environments, have been coupled with 3D physically-based radiative transfer models for retrievals of biochemical and biophysical indicators of vegetation health and condition. With the recent introduction of Terrestrial Laser Scanning (TLS) units, there now exists a means of rapidly measuring intricate structural details of vegetation canopies, which can also serve as input into 3D radiative transfer models. In this investigation, Intelligent Laser Ranging and Imaging System (ILRIS-3D) data was acquired of individual tree crowns in laboratory, and field-based experiments. The ILRIS-3D uses the Time-Of-Flight (TOF) principle to measure the distances of objects based on the time interval between laser pulse exitance and return, upon reflection from an object. At the laboratory-level, this exploratory study demonstrated and validated innovative approaches for retrieving crown-level estimates of Leaf Area Index (LAI) (r2 = 0.98, rmse = 0.26m2/m2), a critical biophysical parameter for vegetation monitoring and modeling. These methods were implemented and expanded in field experiments conducted in olive (Olea europaea L.) orchards in Cordoba, Spain, where ILRIS-3D observations for 24 structurally-variable trees were made. Robust methodologies were developed to characterize diagnostic architectural parameters, such as tree height (r2 = 0.97, rmse = 0.21m), crown width (r 2 = 0.98, rmse = 0.12m), crown height (r2 = 0.81, rmse = 0.11m), crown volume (r2 = 0.99, rmse = 2.6m3), and LAI (r2 = 0.76, rmse = 0.27m2/ m2). These parameters were subsequently used as direct inputs into the Forest LIGHT (FLIGHT) 3D ray tracing model for characterization of the spectral behavior of the olive crowns. Comparisons between FLIGHT-simulated spectra and measured data showed small differences in the visible (measurements were significantly correlated to TLS-derived tree crown complexity metrics. The specific implications of internal crown

  13. Three-dimensional fabric analysis for anisotropic material using multi-directional scanning line. Application to x-ray CI image

    International Nuclear Information System (INIS)

    Takemura, Takato; Takahashi, Manabu; Oda, Masanobu; Hirai, Hidekazu; Murakoshi, Atsushi; Miura, Makoto

    2007-01-01

    In microscopic analysis, materials are characterized by a three-dimensional (3D) microstructure which is composed of constituent elements such as pores, voids and cracks. A material's mechanical and hydrological properties are strongly dependent on its microstructure. In order to discuss the mechanics of geomaterials on a microstructural level, detailed information on their 3D macrostructure is required. X-ray computed tomography is a powerful non-destructive method for determining the microstructure, however it can be difficult to determine a material's microstructure from the reconstructed 3D image. We successfully evaluated the 3D microstructural anisotropy of porous and fibrous materials using a multi-directional scanning line method that employs straightforward image analysis, and its results were visualized using stereonet projection. (author)

  14. Two-dimensional and three-dimensional CT analysis of congenital hip dysplasia in the older child and adult

    International Nuclear Information System (INIS)

    Magid, D.; Fishman, E.K.; Brooker, A.F.; Sponseller, P.D.

    1987-01-01

    In the older child or adult with congenital dysplasia of the hip, a spectrum of developmental abnormalities of the femoral head, neck, and acetabulum produce progressive hip dysfunction, pain, and premature arthritis. Treatment is oriented to restoring normal and pain-free function, although (unlike the infant with successfully treated dislocation) a truly normal hip cannot be restored. For these patients, who may require extensive reconstruction, transaxial CT with both static 2D (coronal and sagittal) and animated volumetric 3D image reformatting offers the most complete, accurate, and integrated approach to diagnosis and therapeutic planning. Parameters preoperatively assessed include head subluxation, neck anteversion, quadrilateral plate thickness, degree of dysplasia, potential for concentric reduction, acetabular capacity, and muscle status. Postoperatively, both immediate and long-term results or complications are easily assessed and readily compared

  15. Real-time three dimensional CT and MRI to guide interventions for congenital heart disease and acquired pulmonary vein stenosis.

    Science.gov (United States)

    Suntharos, Patcharapong; Setser, Randolph M; Bradley-Skelton, Sharon; Prieto, Lourdes R

    2017-10-01

    To validate the feasibility and spatial accuracy of pre-procedural 3D images to 3D rotational fluoroscopy registration to guide interventional procedures in patients with congenital heart disease and acquired pulmonary vein stenosis. Cardiac interventions in patients with congenital and structural heart disease require complex catheter manipulation. Current technology allows registration of the anatomy obtained from 3D CT and/or MRI to be overlaid onto fluoroscopy. Thirty patients scheduled for interventional procedures from 12/2012 to 8/2015 were prospectively recruited. A C-arm CT using a biplane C-arm system (Artis zee, VC14H, Siemens Healthcare) was acquired to enable 3D3D registration with pre-procedural images. Following successful image fusion, the anatomic landmarks marked in pre-procedural images were overlaid on live fluoroscopy. The accuracy of image registration was determined by measuring the distance between overlay markers and a reference point in the image. The clinical utility of the registration was evaluated as either "High", "Medium" or "None". Seventeen patients with congenital heart disease and 13 with acquired pulmonary vein stenosis were enrolled. Accuracy and benefit of registration were not evaluated in two patients due to suboptimal images. The distance between the marker and the actual anatomical location was 0-2 mm in 18 (64%), 2-4 mm in 3 (11%) and >4 mm in 7 (25%) patients. 3D3D registration was highly beneficial in 18 (64%), intermediate in 3 (11%), and not beneficial in 7 (25%) patients. 3D3D registration can facilitate complex congenital and structural interventions. It may reduce procedure time, radiation and contrast dose.

  16. Evaluation strategies in CT scanning

    DEFF Research Database (Denmark)

    In this talk, dimensional measurement results using different measuring strategies applied in different inspection software packages for volume and surface data analysis are presented. The influence of the strategy on the dimensional measurement is determined by calculating the measurement...... uncertainty. This investigation includes measurements of two industrial items, an aluminum pipe connector and a plastic toggle, a hearing aid component. These are measured using a commercial CT scanner. Traceability is transferred using tactile and optical coordinate measuring machines, which are used...

  17. Optical-CT scanning of polymer gels

    Energy Technology Data Exchange (ETDEWEB)

    Oldham, M [Radiation Oncology Physics, Duke University Medical Center, Duke University, NC (United States)

    2004-01-01

    The application of optical-CT scanning to achieve accurate high-resolution 3D dosimetry is a subject of current interest. The purpose of this paper is to provide a brief overview of past research and achievements in optical-CT polymer gel dosimetry, and to review current issues and challenges. The origins of optical-CT imaging of light-scattering polymer gels are reviewed. Techniques to characterize and optimize optical-CT performance are presented. Particular attention is given to studies of artifacts in optical-CT imaging, an important area that has not been well studied to date. The technique of optical-CT simulation by Monte-Carlo modeling is introduced as a tool to explore such artifacts. New simulation studies are presented and compared with experimental data.

  18. Optical-CT scanning of polymer gels

    International Nuclear Information System (INIS)

    Oldham, M

    2004-01-01

    The application of optical-CT scanning to achieve accurate high-resolution 3D dosimetry is a subject of current interest. The purpose of this paper is to provide a brief overview of past research and achievements in optical-CT polymer gel dosimetry, and to review current issues and challenges. The origins of optical-CT imaging of light-scattering polymer gels are reviewed. Techniques to characterize and optimize optical-CT performance are presented. Particular attention is given to studies of artifacts in optical-CT imaging, an important area that has not been well studied to date. The technique of optical-CT simulation by Monte-Carlo modeling is introduced as a tool to explore such artifacts. New simulation studies are presented and compared with experimental data

  19. Three dimensional and high resolution magnetic resonance imaging of the inner ear. Normal ears and anomaly scanned with 3D-CISS sequence

    International Nuclear Information System (INIS)

    Edamatsu, Hideo; Uechi, Yoko; Honjyo, Shiro; Yamashita, Koichi; Tonami, Hisao.

    1997-01-01

    The MRI system used in this study was a new scanning sequence, 3D-CISS (Three dimensional-constructive interference in steady state) with 1.5 Tesla. Ten normal ears and one ear with Mondini type anomaly were scanned and reconstructed. In imagings of normal inner ears, the cochlea has three spiral layers; basal, middle and apical turns. Each turn was separated into three parts; the scala vestibuli, osseous spiral lamina and scala tympani. Three semicircular ducts, utricle and saccule were also reconstructed in one frame. In the inner ear of Mondini anomaly, 3D MRI showed cochlear aplasia, hypoplasia of semicircular ducts and widely dilated vestibule. The imaging was identical with findings of ''common cavity''. The anomaly was easily recognized in 3D MRI more than in 2D imagings. The detailed and cubic imagings of the Mondini anomaly in 3D MRI could not be observed with conventional 2D MRI. 3D MRI is not invasive method and can scan a target very quickly. (author)

  20. Comparison of Bolton analysis and Little’s irregularity index on laser scanned three-dimensional digital study models with conventional study models

    Science.gov (United States)

    Kurnia, H.; Noerhadi, N. A. I.

    2017-08-01

    Three-dimensional digital study models were introduced following advances in digital technology. This study was carried out to assess the reliability of digital study models scanned by a laser scanning device newly assembled. The aim of this study was to compare the digital study models and conventional models. Twelve sets of dental impressions were taken from patients with mild-to-moderate crowding. The impressions were taken twice, one with alginate and the other with polyvinylsiloxane. The alginate impressions were made into conventional models, and the polyvinylsiloxane impressions were scanned to produce digital models. The mesiodistal tooth width and Little’s irregularity index (LII) were measured manually with digital calipers on the conventional models and digitally on the digital study models. Bolton analysis was performed on each study models. Each method was carried out twice to check for intra-observer variability. The reproducibility (comparison of the methods) was assessed using independent-sample t-tests. The mesiodistal tooth width between conventional and digital models did not significantly differ (p > 0.05). Independent-sample t-tests did not identify statistically significant differences for Bolton analysis and LII (p = 0.603 for Bolton and p = 0894 for LII). The measurements of the digital study models are as accurate as those of the conventional models.

  1. Three-dimensional reconstruction used in the diagnosis and treatment of depressed fracture of skull

    International Nuclear Information System (INIS)

    Li Liang; Luo Zhikun; Lin Xiaohui; Liu Shuyi; Chen Xu; Liu Chenghui

    2005-01-01

    Objective: To evaluate three-dimensional reconstruction used in the diagnosis and management of depressed fracture of skull. Methods: The images of CT scan and three-dimensional reconstruction in 23 patients with depressed fracture of skull were studied. The clinical treatment was guided by the images. Results: The fracture site and depth in all 23 cases were well demonstrated in the imaging of three-dimensional reconstruction, which successfully guided the clinical management in every case. Conclusion: Three-dimensional reconstruction is a valuable modality for the diagnosis and management of depressed fracture of skull. (authors)

  2. Noninvasive computerized scanning method for the correlation between the facial soft and hard tissues for an integrated three-dimensional anthropometry and cephalometry.

    Science.gov (United States)

    Galantucci, Luigi Maria; Percoco, Gianluca; Lavecchia, Fulvio; Di Gioia, Eliana

    2013-05-01

    The article describes a new methodology to scan and integrate facial soft tissue surface with dental hard tissue models in a three-dimensional (3D) virtual environment, for a novel diagnostic approach.The facial and the dental scans can be acquired using any optical scanning systems: the models are then aligned and integrated to obtain a full virtual navigable representation of the head of the patient. In this article, we report in detail and further implemented a method for integrating 3D digital cast models into a 3D facial image, to visualize the anatomic position of the dentition. This system uses several 3D technologies to scan and digitize, integrating them with traditional dentistry records. The acquisitions were mainly performed using photogrammetric scanners, suitable for clinics or hospitals, able to obtain high mesh resolution and optimal surface texture for the photorealistic rendering of the face. To increase the quality and the resolution of the photogrammetric scanning of the dental elements, the authors propose a new technique to enhance the texture of the dental surface. Three examples of the application of the proposed procedure are reported in this article, using first laser scanning and photogrammetry and then only photogrammetry. Using cheek retractors, it is possible to scan directly a great number of dental elements. The final results are good navigable 3D models that integrate facial soft tissue and dental hard tissues. The method is characterized by the complete absence of ionizing radiation, portability and simplicity, fast acquisition, easy alignment of the 3D models, and wide angle of view of the scanner. This method is completely noninvasive and can be repeated any time the physician needs new clinical records. The 3D virtual model is a precise representation both of the soft and the hard tissue scanned, and it is possible to make any dimensional measure directly in the virtual space, for a full integrated 3D anthropometry and

  3. Three-Dimensional post-myelographic CT reconstruction in the diagnosis and therapy planning for spinal development disorders; Dreidimensionale postmyelographische CT-Rekonstruktion in der Diagnostik und Therapieplanung spinaler Entwicklungsstoerungen

    Energy Technology Data Exchange (ETDEWEB)

    Wicht, L. [Strahlenklinik und Poliklinik, Virchow Klinikum, Humboldt-Univ. zu Berlin (Germany); Schedel, H. [Strahlenklinik und Poliklinik, Virchow Klinikum, Humboldt-Univ. zu Berlin (Germany); Benndorf, G. [Strahlenklinik und Poliklinik, Virchow Klinikum, Humboldt-Univ. zu Berlin (Germany); Beier, J. [Strahlenklinik und Poliklinik, Virchow Klinikum, Humboldt-Univ. zu Berlin (Germany); Haberl, H. [Neurochirurgische Abt., Virchow-Klinikum, Humboldt-Univ. zu Berlin (Germany); Felix, R. [Strahlenklinik und Poliklinik, Virchow Klinikum, Humboldt-Univ. zu Berlin (Germany)

    1996-05-01

    Dysrhaphia is often associated with severe osseous aberrations of the spine such as, for example scoliosis, hemivertebra, and synostosis. With the advanced possibilities of the post-processing of CT-data (segmentation, three-dimensional reconstruction), post-myelo-CT is an excellent method for the evaluation of osseous structures and the myelon in preoperative planning. (orig.) [Deutsch] Dysraphien gehen haeufig mit ausgepraegten ossaeren Veraenderungen der Wirbelsaeule wie Skoliose, Halbwirbelbildungen und Synostosen einher. Mit den verbesserten Moeglichkeiten der Datennachbearbeitung (Segmentierung, 3D-dimensionale Rekonstruktion) stellt die postmyelographische Computertomographie vor allem bei komplexen Fehlbildungen ein geeignetes Verfahren zur praeoperativen Beurteilung der ossaeren Strukturen der Wirbelsaeule und des Myelons dar. (orig.)

  4. Comparison of planning target volumes based on three-dimensional and four-dimensional CT imaging of thoracic esophageal cancer

    Directory of Open Access Journals (Sweden)

    Wang W

    2016-08-01

    Full Text Available Wei Wang, Jianbin Li, Yingjie Zhang, Qian Shao, Min Xu, Tingyong Fan, Jinzhi Wang Department of Radiation Oncology, Shandong Cancer Hospital Affiliated to Shandong University, Shandong Academy of Medical Sciences, Shandong, People’s Republic of China Background and purpose: To investigate the definition of planning target volumes (PTVs based on four-dimensional computed tomography (4DCT compared with conventional PTV definition and PTV definition using asymmetrical margins for thoracic primary esophageal cancer. Materials and methods: Forty-three patients with esophageal cancer underwent 3DCT and 4DCT simulation scans during free breathing. The motions of primary tumors located in the proximal (group A, middle (group B, and distal (group C thoracic esophagus were obtained from the 4DCT scans. PTV3D was defined on 3DCT using the tumor motion measured based on 4DCT, PTV conventional (PTVconv was defined on 3DCT by adding a 1.0 cm margin to the clinical target volume, and PTV4D was defined as the union of the target volumes contoured on the ten phases of the 4DCT images. The centroid positions, volumetric differences, and dice similarity coefficients were evaluated for all PTVs. Results: The median centroid shifts between PTV3D and PTV4D and between PTVconv and PTV4D in all three dimensions were <0.3 cm for the three groups. The median size ratios of PTV4D to PTV3D were 0.80, 0.88, and 0.71, and PTV4D to PTVconv were 0.67, 0.73, and 0.76 (χ2=–3.18, –2.98, and –3.06; P=0.001, 0.003, and 0.002 for groups A, B, and C, respectively. The dice similarity coefficients were 0.87, 0.90, and 0.81 between PTV4D and PTV3D and 0.80, 0.84, and 0.83 between PTV4D and PTVconv (χ2=–3.18, –2.98, and –3.06; P=0.001, 0.003, and 0.002 for groups A, B, and C, respectively. The difference between the degree of inclusion of PTV4D in PTV3D and that of PTV4D in PTVconv was <2% for all groups. Compared with PTVconv, the amount of irradiated normal tissue

  5. CT scan of bacterial and aseptic meningitis

    International Nuclear Information System (INIS)

    Takemoto, Kazumasa; Saiwai, Shigeo; Tamaoka, Koichi

    1983-01-01

    CT scans of the patients with aseptic and bacterial meningitis were reviewed and compared to previous reports. In aseptic meningitis, no abnormal CT findings were observed. In bacterial meningitis, CT findings were ventricular dilatation, subdural fluid collection, parenchymal low density, intracerebral hematoma and meningeal enhancement after contrast injection. Three patients among 48 suffered from status epileptics during the course of the illness. All of 3 patients developed parenchymal inhomogeneous low density and progressive ventricular dilatation which did not improve after ventricular peritoneal shunt surgery. We believe that these changes are most likely due to hypoxic hypoxemia during epileptic seizure and meningitis itself seems to play a little role. (author)

  6. Incidental apical disease at CT scanning

    International Nuclear Information System (INIS)

    McLoud, T.C.; Satoh, K.; Shepard, J.O.; Moore, E.H.; Kosiuk, J.P.

    1990-01-01

    Apical caps are commonly noted on standard radiographs. This paper determines how often abnormalities in the extreme apex of the lung could be identified on CT scans obtained for other reasons. A total of 158 consecutive CT scans were reviewed prospectively. Excluded were patients with obvious upper lobe pleural or parenchymal disease. Apical abnormalities were identified in 74 (46.8%) of the 158 cases. The prevalence increased with age (19% in the 8-39-year age group and 82% in patients older than 80 years). Opacities were unilateral in 44.5% and bilateral in 55.5%. The most common abnormality was linear opacities (95%)

  7. Three-dimensional CT might be a potential evaluation modality in correction of asymmetrical masseter muscle hypertrophy by botulinum toxin injection.

    Science.gov (United States)

    No, Yeon A; Ahn, Byeong Heon; Kim, Beom Joon; Kim, Myeung Nam; Hong, Chang Kwon

    2016-01-01

    For correction of this asymmetrical hypertrophy, botulinum toxin type A (BTxA) injection is one of convenient treatment modalities. Unfortunately, physical examination of masseter muscle is not enough to estimate the exact volume of muscle hypertrophy difference. Two Koreans, male and female, of bilateral masseter hypertrophy with asymmetricity were evaluated. BTxA (NABOTA(®), Daewoong, Co. Ltd., Seoul, Korea) was injected at master muscle site with total 50 U (25 U at each side) and volume change was evaluated with three-dimensional (3D) CT image analysis. Maximum reduction of masseter hypertrophy was recognized at 2-month follow-up and reduced muscle size started to restore after 3 months. Mean reduction of masseter muscle volume was 36% compared with baseline. More hypertrophied side of masseter muscle presented 42% of volume reduction at 2-month follow-up but less hypertrophied side of masseter muscle showed 30% of volume shrinkage. In conclusion, 3D CT image analysis might be the exact evaluation tool for correction of asymmetrical masseter hypertrophy by botulinum toxin injection.

  8. Semiautomatic three-dimensional CT ventricular volumetry in patients with congenital heart disease: agreement between two methods with different user interaction.

    Science.gov (United States)

    Goo, Hyun Woo; Park, Sang-Hyub

    2015-12-01

    To assess agreement between two semi-automatic, three-dimensional (3D) computed tomography (CT) ventricular volumetry methods with different user interactions in patients with congenital heart disease. In 30 patients with congenital heart disease (median age 8 years, range 5 days-33 years; 20 men), dual-source, multi-section, electrocardiography-synchronized cardiac CT was obtained at the end-systolic (n = 22) and/or end-diastolic (n = 28) phase. Nineteen left ventricle end-systolic (LV ESV), 28 left ventricle end-diastolic (LV EDV), 22 right ventricle end-systolic (RV ESV), and 28 right ventricle end-diastolic volumes (RV EDV) were successfully calculated using two semi-automatic, 3D segmentation methods with different user interactions (high in method 1, low in method 2). The calculated ventricular volumes of the two methods were compared and correlated. A P value volumetry shows good agreement and high correlation between the two methods, but method 2 tends to slightly underestimate LV ESV, LV EDV, and RV ESV.

  9. Scanning and contrast enhancement protocols for multi-slice CT in evaluation of the upper abdomen

    International Nuclear Information System (INIS)

    Awai, Kazuo; Onishi, Hiromitsu; Takada, Koichi; Yamaguchi, Yasuo; Eguchi, Nobuko; Hiraishi, Kumiko; Hori, Shinichi

    2000-01-01

    The advent of multi-slice CT is one of the quantum leaps in computed tomography since the introduction of helical CT. Multi-slice CT can rapidly scan a large longitudinal (z-axis) volume with high longitudinal resolution and low image artifacts. The rapid volume coverage speed of multi-slice CT can increase the difficulty in optimizing the delay time between the beginning of contrast material injection and the acquisition of images and we need accurate knowledge about optimal temporal window for adequate contrast enhancement. High z-axis resolution of multi-slice can improve the quality of three-dimensional images and MPR images and we must select adequate slice thickness and slice intervals in each case. We discuss basic considerations for adequate contrast enhancement and scanning protocols by multi-slice CT scanner in the upper abdomen. (author)

  10. Two- and three-dimensional evaluation of the acetabulum in the pediatric patient

    International Nuclear Information System (INIS)

    Magid, D.; Fishman, E.K.; Sponseller, P.D.

    1987-01-01

    Complex anatomic structures such as the hip and acetabulum are best evaluated with the use of two- and three-dimensional reconstruction techniques and standard transaxial CT data. CT scans of children with various hip pathologies, including congenital hip dislocation, slipped capital femoral epiphyses, hip dysplasias, dwarfism, and acetabular fractures, were reviewed to determine the value of two- and three-dimensional imaging. The advantages of two-dimensional imaging techniques (sequential coronal/sagittal reconstruction) and three-dimensional valumetric imaging techniques (using real-time video display) are illustrated with specific examples

  11. Diagnostic value of axial CT scan

    International Nuclear Information System (INIS)

    Kiuchi, Sousuke

    1983-01-01

    Axial CT scan was used to investigate the radiological details of the temporal bone of 33 patients with chronic otitis media, secondary cholesteatoma, sensorineural hearing loss, Meniere disease, vertigo, facial spasm, and neoplasma. The axial scans showed anatomic details of the temporal bone, and at the same time clearly demonstrated the extent of the soft-tissue masses in the middle ears, as well as the destructions of the ossicles. Bone changes of the anterior walls of the epitympanum and external auditory meatus were more clearly demonstrated than by coronary CT scan. However, the axial scan had the disadvantages in demonstrating the stapes, crista transversa, and the mastoid portion of the facial canal. (author)

  12. Accuracy of renal volume assessment in children by three-dimensional sonography; Nierenvolumetrie im Kindesalter: Genauigkeit der dreidimensionalen Sonographie im Vergleich zur konventionellen Sonographie und CT/MRT

    Energy Technology Data Exchange (ETDEWEB)

    Fritz, G.A.; Riccabona, M.; Bohdal, G. [Klinik fuer Radiologie, Universitaetsklinikum Graz (Austria); Quehenberger, F. [Inst. fuer medizinische Informatik, Statistik und Dokumentation, Universitaetsklinikum Graz (Austria)

    2003-04-01

    Purpose: Prospective evaluation of the accuracy of three-dimensional ultrasound (3DUS) to assess the renal parenchymal volume. Materials and Methods: CT, MRI, 2DUS and 3DUS were used to measure the renal volume in 40 patients (range: neonate to 17 years; mean age: 8.95 years). The 3DUS was determined with a Voluson 730 (Kretztechnik, GE) or an external 3D-system (EchoTech, GE) using electromagnetic positioning sensors attached to conventional 2DUS-equipment. The 2DUS volume was calculated with the ellipsoid equation and the 3DUS volume computed with the system integrated software. For CT and MRI, planimetric analysis was used to determine the renal parenchymal volume, whereby the dilated collecting system of a hydronephrosis was subtracted to obtain the real renal parenchymal volume. The results of 2DUS and 3DUS were compared to the results of CT and MRI, and inter- and intraobserver variabilities were calculated. Results: In 74 of 77 kidneys, the 3DUS study was of diagnostic quality. The accuracy of the 3DUS volumes compared well to the CT and MRI volumes with a mean difference of -1.8 {+-} 4.6% versus a mean difference of -2.4 {+-} 15.4% for 2DUS. In normal kidneys, the accuracy was -2.6 {+-} 4.4% for 3DUS and -3.8 {+-} 14.7% for 2DUS. In hydronephrosis, the accuracy was +4.0 {+-} 5.9% and +9.6 {+-} 21.3%, respectively, indicating that 3DUS is more accurate than 2DUS, particularly in kidneys with a dilated collecting system. Inter- and intraobserver variabilities were {+-} 7.3% and {+-} 5.3%. Conclusion: For assessing the renal parenchymal volume in children, 3DUS is feasible and comparable to CT and MRI. (orig.) [German] Studienziel: Prospektive Evaluation der Genauigkeit des drei-dimensionalen Ultraschalls (3DUS) bei der Volumetrie der kindlichen Niere im Vergleich zur CT/MRT. Methode: Bei 40 Patienten (Alter: 0 - 17 Jahre) mit einer klinisch indizierten CT/MRT des Abdomens oder des Harntrakts wurde zusaetzlich ein 2D- und 3DUS inklusive Volumetrie des

  13. Three dimensional strained semiconductors

    Science.gov (United States)

    Voss, Lars; Conway, Adam; Nikolic, Rebecca J.; Leao, Cedric Rocha; Shao, Qinghui

    2016-11-08

    In one embodiment, an apparatus includes a three dimensional structure comprising a semiconductor material, and at least one thin film in contact with at least one exterior surface of the three dimensional structure for inducing a strain in the structure, the thin film being characterized as providing at least one of: an induced strain of at least 0.05%, and an induced strain in at least 5% of a volume of the three dimensional structure. In another embodiment, a method includes forming a three dimensional structure comprising a semiconductor material, and depositing at least one thin film on at least one surface of the three dimensional structure for inducing a strain in the structure, the thin film being characterized as providing at least one of: an induced strain of at least 0.05%, and an induced strain in at least 5% of a volume of the structure.

  14. Change in the collateral and accessory collateral ligament lengths of the proximal interphalangeal joint using cadaveric model three-dimensional laser scanning.

    Science.gov (United States)

    Sandhu, S S; Dreckmann, S; Binhammer, P A

    2016-05-01

    The purpose of this study was to assess the lengths of the index and middle finger proximal interphalangeal joint ligaments and determine the relative changes in the collateral and accessory collateral ligament lengths at 0°, 45° and 90° flexion. We generated three-dimensional scans of 16 finger (eight index and eight middle) proximal interphalangeal joints to assess relative changes in ligament length. Significant changes were found between 45°-90° and 0°-90° for the ulnar collateral ligament of the index finger and both collateral ligaments of the middle finger between 45°-90° and 0°-90°. No significant changes in length were found for the radial collateral ligament of the index finger or the accessory collateral ligaments of the index and middle fingers. Overall, it was found that the collateral ligament length changed significantly, but there was no significant change in the accessory collateral ligaments. Therapeutic IV. © The Author(s) 2015.

  15. Accuracy and precision of polyurethane dental arch models fabricated using a three-dimensional subtractive rapid prototyping method with an intraoral scanning technique.

    Science.gov (United States)

    Kim, Jae-Hong; Kim, Ki-Baek; Kim, Woong-Chul; Kim, Ji-Hwan; Kim, Hae-Young

    2014-03-01

    This study aimed to evaluate the accuracy and precision of polyurethane (PUT) dental arch models fabricated using a three-dimensional (3D) subtractive rapid prototyping (RP) method with an intraoral scanning technique by comparing linear measurements obtained from PUT models and conventional plaster models. Ten plaster models were duplicated using a selected standard master model and conventional impression, and 10 PUT models were duplicated using the 3D subtractive RP technique with an oral scanner. Six linear measurements were evaluated in terms of x, y, and z-axes using a non-contact white light scanner. Accuracy was assessed using mean differences between two measurements, and precision was examined using four quantitative methods and the Bland-Altman graphical method. Repeatability was evaluated in terms of intra-examiner variability, and reproducibility was assessed in terms of inter-examiner and inter-method variability. The mean difference between plaster models and PUT models ranged from 0.07 mm to 0.33 mm. Relative measurement errors ranged from 2.2% to 7.6% and intraclass correlation coefficients ranged from 0.93 to 0.96, when comparing plaster models and PUT models. The Bland-Altman plot showed good agreement. The accuracy and precision of PUT dental models for evaluating the performance of oral scanner and subtractive RP technology was acceptable. Because of the recent improvements in block material and computerized numeric control milling machines, the subtractive RP method may be a good choice for dental arch models.

  16. Three-dimensional scanning near field optical microscopy (3D-SNOM) imaging of random arrays of copper nanoparticles: implications for plasmonic solar cell enhancement.

    Science.gov (United States)

    Ezugwu, Sabastine; Ye, Hanyang; Fanchini, Giovanni

    2015-01-07

    In order to investigate the suitability of random arrays of nanoparticles for plasmonic enhancement in the visible-near infrared range, we introduced three-dimensional scanning near-field optical microscopy (3D-SNOM) imaging as a useful technique to probe the intensity of near-field radiation scattered by random systems of nanoparticles at heights up to several hundred nm from their surface. We demonstrated our technique using random arrays of copper nanoparticles (Cu-NPs) at different particle diameter and concentration. Bright regions in the 3D-SNOM images, corresponding to constructive interference of forward-scattered plasmonic waves, were obtained at heights Δz ≥ 220 nm from the surface for random arrays of Cu-NPs of ∼ 60-100 nm in diameter. These heights are too large to use Cu-NPs in contact of the active layer for light harvesting in thin organic solar cells, which are typically no thicker than 200 nm. Using a 200 nm transparent spacer between the system of Cu-NPs and the solar cell active layer, we demonstrate that forward-scattered light can be conveyed in 200 nm thin film solar cells. This architecture increases the solar cell photoconversion efficiency by a factor of 3. Our 3D-SNOM technique is general enough to be suitable for a large number of other applications in nanoplasmonics.

  17. Simulation and experimental studies of three-dimensional (3D) image reconstruction from insufficient sampling data based on compressed-sensing theory for potential applications to dental cone-beam CT

    International Nuclear Information System (INIS)

    Je, U.K.; Lee, M.S.; Cho, H.S.; Hong, D.K.; Park, Y.O.; Park, C.K.; Cho, H.M.; Choi, S.I.; Woo, T.H.

    2015-01-01

    In practical applications of three-dimensional (3D) tomographic imaging, there are often challenges for image reconstruction from insufficient sampling data. In computed tomography (CT), for example, image reconstruction from sparse views and/or limited-angle (<360°) views would enable fast scanning with reduced imaging doses to the patient. In this study, we investigated and implemented a reconstruction algorithm based on the compressed-sensing (CS) theory, which exploits the sparseness of the gradient image with substantially high accuracy, for potential applications to low-dose, high-accurate dental cone-beam CT (CBCT). We performed systematic simulation works to investigate the image characteristics and also performed experimental works by applying the algorithm to a commercially-available dental CBCT system to demonstrate its effectiveness for image reconstruction in insufficient sampling problems. We successfully reconstructed CBCT images of superior accuracy from insufficient sampling data and evaluated the reconstruction quality quantitatively. Both simulation and experimental demonstrations of the CS-based reconstruction from insufficient data indicate that the CS-based algorithm can be applied directly to current dental CBCT systems for reducing the imaging doses and further improving the image quality

  18. CT scanning in pediatric head trauma: correlation of clinical features with CT scan diagnosis

    International Nuclear Information System (INIS)

    Arkoncel, Mary Ann P.; Posadas, Ma. Belen A.

    1997-01-01

    A retrospective review was conducted on 205 cases of pediatric head trauma for which cranial computed tomography scans were done at the Makati Medical Center, to determine which clinical features might positively predict an abnormality on CT scan. The clinical findings of loss of consciousness, GCS < 12, vomiting headache, seizures, and focal abnormalities on Neurologic Examination were significantly associated with abnormal findings on CT scan. However, a significant discrepancy does exist as to how accurately clinical findings do in fact predict normal and abnormal CT scan findings. Such a discrepancy allows us to conclude that a more liberal use of CT Scanning in cases of pediatric head trauma must be stressed to insure proper diagnosis. This study shows that when a patient presents with the aforementioned positive signs and symptoms, or with a focal neurologic deficit, or in combination, a 60-100 % positive prediction of abnormal CT Scan can be made. However, prediction of normal CT Scan is only 0-40%. (Author)

  19. Contrast bolus technique with rapid CT scanning

    International Nuclear Information System (INIS)

    Arnold, H.; Kuehne, D.; Rohr, W.; Heller, M.

    1981-01-01

    Twenty-three patients complying with the clinical criteria for brain death were studied by contrast-enhanced CT. In all but one, the great intracranial vessels escaped visualization; accordingly, angiography demonstrated cerebral circulatory arrest. In the remaining case, faint enhancement of the circle of Willis corresponded to angiographic demonstration of the proximal segments of cerebral arteris. Neither in normal brain nor in dead brain did slow CT scanning disclose any postcontrast increase in parenchymal attenuation. An improved technique is proposed to demonstrate the transit of the contrast bolus by rapid CT with image splitting. If cerebral blood flow is preserved, the grey and white matter will enhance significantly following administration of contrast medium. Vice versa, the absence of enhancement confirms brain death, even in instances in which the great cerebral vessels are obscured by hemorrhage or other extensive lesions. Two additional cases of brain death were evaluated by rapid CT scanning. As to brain death, the technique obviates the need for angiography or radionuclide angiography, usually applied in prospective organ donors, because its informative content is superior to that of either method. The CT technique described affords a reliable and safe diagnosis of brain death, and can be interpreted easily. (orig.)

  20. Particle coagulation in molten metal based on three-dimensional analysis of cluster by x-ray micro-computer tomography (CT)

    International Nuclear Information System (INIS)

    Li, Tao; Shimasaki, Shin-ichi; Taniguchi, Shoji; Narita, Shunsuke; Uesugi, Kentaro

    2013-01-01

    Particle coagulation plays a key role in steel refining process to remove inclusions. Many research works focus on the behaviors of particle coagulation. To reveal its mechanism water model experiments have been performed by some researchers including the authors' group. In this paper, experiments of particle coagulation were carried out with molten Al including SiC particles in a mechanically agitated crucible with two baffles. Particle coagulation and formation of clusters were observed on the microscopy images of as-polished samples. Three-dimensional (3D) analysis of the clusters in solidified Al was implemented by X-ray micro CT available at SPring-8. The methods to distinguish clusters on two-dimensional (2D) cross-sectional images were discussed, which were established in the previous works by the present authors' group. The characteristics of the 3D SiC clusters and their 2D cross-sections were analyzed. The statistical ranges of the parameters for 2D clusters were used as criterions to distinguish the clusters on 2D microscopy images from the as-polished samples. The kinetics of SiC particle coagulation was studied by the measured cluster number density and size using our program to distinguish cluster in 2D cross-sectional images according to 3D information (DC-2D-3D). The calculated and experimental results of the SiC particle coagulation in molten Al agree well with each other. (author)

  1. Morphological characteristics of the bony birth canal in patients with developmental dysplasia of the hip (DDH). Investigation by three-dimensional CT

    Energy Technology Data Exchange (ETDEWEB)

    Kojima, Seiichi; Kobayashi, Seneki; Saito, Naoto; Nawata, Masashi; Horiuchi, Hiroshi; Takaoka, Kunio [Shinshu Univ., Matsumoto, Nagano (Japan). School of Medicine

    2001-07-01

    We investigated the three-dimensional morphological characteristics of the pelvis in adult female patients with developmental dysplasia of the hip (DDH), using computerized tomography (CT) images. Forty-two subjects with normal hips and 40 DDH patients were recruited for the study. In the DDH group, the average transverse diameter of the pelvic inlet was significantly less and the average transverse diameter of the pelvic outlet was significantly greater than the measurements in the normal group. Further, the bony birth canal in DDH patients exhibited a higher incidence of anthropoid-type geometry, as defined by a longer sagittal diameter relative to the transverse diameter of the pelvic inlet. These findings indicate a characteristic pelvic geometry and suggest different development of the pelvis in the transverse direction in DDH patients. In addition, the obstetric conjugate length/transverse diameter of the pelvic inlet ratio was correlated to the degree of severity of acetabular dysplasia. This finding suggests that DDH is a manifestation of a developmental characteristic of the pelvis. (author)

  2. Retrospectively ECG-gated multi-detector row CT of the chest: does ECG-gating improve three-dimensional visualization of the bronchial tree?

    International Nuclear Information System (INIS)

    Schertler, T.; Wildermuth, S.; Willmann, J.K.; Crook, D.W.; Marincek, B.; Boehm, T.

    2004-01-01

    Purpose: To determine the impact of retrospectively ECG-gated multi-detector row CT (MDCT) on three-dimensional (3D) visualization of the bronchial tree and virtual bronchoscopy (VB) as compared to non-ECG-gated data acquisition. Materials and Methods: Contrast-enhanced retrospectively ECG-gated and non-ECG-gated MDCT of the chest was performed in 25 consecutive patients referred for assessment of coronary artery bypass grafts and pathology of the ascending aorta. ECG-gated MDCT data were reconstructed in diastole using an absolute reverse delay of -400 msec in all patients. In 10 patients additional reconstructions at -200 msec, -300 msec, and -500 msec prior to the R-wave were performed. Shaded surface display (SSD) and virtual bronchoscopy (VB) for visualization of the bronchial segments was performed with ECG-gated and non-ECG-gated MDCT data. The visualization of the bronchial tree underwent blinded scoring. Effective radiation dose and signal-to-noise ratio (SNR) for both techniques were compared. Results: There was no significant difference in visualizing single bronchial segments using ECG-gated compared to non-ECG-gated MDCT data. However, the total sum of scores for all bronchial segments visualized with non-ECG-gated MDCT was significantly higher compared to ECG-gated MDCT (P [de

  3. The role of three-dimensional multidetector CT gastrography in the preoperative imaging of stomach cancer: Emphasis on detection and localization of the tumor

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jin Woong; Shin, Sang Soo; Heo, Suk Hee; Lim, Hyo Soon; Park, Young Kyu; Jeong, Yong Yeon; Kang, Heoung Keun [Chonnam National University Medical School, Gwangju (Korea, Republic of); Lim, Nam Yeol [Dept. of Radiology, Chonnam National University Hospital, Gwangju (Korea, Republic of)

    2015-02-15

    Multidetector CT (MDCT) gastrography has been regarded as a promising technique for the preoperative imaging of gastric cancer. It has the ability to produce various three-dimensional (3D) images. Because 3D reconstruction images are more effective and intuitive for recognizing abnormal changes in the gastric folds and subtle mucosal nodularity than two-dimensional images, 3D MDCT gastrography can enhance the detection rate of early gastric cancer, which, in turn, contributes to the improvement of the accuracy of preoperative tumor (T) staging. In addition, shaded surface display and tissue transition projection images provide a global view of the stomach, with the exact location of gastric cancer, which may replace the need for barium studies. In this article, we discuss technical factors in producing high-quality MDCT gastrographic images and present cases demonstrating the usefulness of MDCT gastrography for the detection and T staging of gastric cancer while emphasizing the significance of preoperative localization of gastric cancer in terms of surgical margin.

  4. Abnormal course of the vertebral artery at the craniovertebral junction in patients with Down syndrome visualized by three-dimensional CT angiography

    International Nuclear Information System (INIS)

    Yamazaki, Masashi; Okawa, Akihiko; Hashimoto, Mitsuhiro; Aiba, Atsuomi; Someya, Yukio; Koda, Masao

    2008-01-01

    We determined the incidence of vertebral artery (VA) anomalies at the craniovertebral junction (CVJ) in patients with Down syndrome, and characterized the VA anomalies. The course of the VA in 46 consecutive patients who were due to undergo posterior arthrodesis surgery at the CVJ were evaluated by three-dimensional CT angiography (3DCTA). Included were five patients with Down syndrome who suffered from myelopathy due to atlantoaxial subluxation. All five patients with Down syndrome also had a simultaneous congenital skeletal anomaly, either os odontoideum or ossiculum terminale. Of the five patients with Down syndrome, three had VA anomalies at the CVJ, two had fenestration and one had a persistent first intersegmental artery. Of the other 41 patients without Down syndrome, five had VA anomalies at the CVJ. The incidence of VA anomalies at the CVJ was much higher in patients with Down syndrome than in those without Down syndrome. In planning surgery in patients with Down syndrome with symptomatic atlantoaxial subluxation and a congenital skeletal anomaly at the CVJ, we should consider the possible presence of VA anomalies. Preoperative 3DCTA allows us to precisely identify an anomalous VA and evaluate the possible risk of intraoperative VA injury in advance. (orig.)

  5. Abnormal course of the vertebral artery at the craniovertebral junction in patients with Down syndrome visualized by three-dimensional CT angiography

    Energy Technology Data Exchange (ETDEWEB)

    Yamazaki, Masashi; Okawa, Akihiko; Hashimoto, Mitsuhiro; Aiba, Atsuomi; Someya, Yukio; Koda, Masao [Chiba University Graduate School of Medicine, Spine Section, Department of Orthopaedic Surgery, Chiba (Japan)

    2008-06-15

    We determined the incidence of vertebral artery (VA) anomalies at the craniovertebral junction (CVJ) in patients with Down syndrome, and characterized the VA anomalies. The course of the VA in 46 consecutive patients who were due to undergo posterior arthrodesis surgery at the CVJ were evaluated by three-dimensional CT angiography (3DCTA). Included were five patients with Down syndrome who suffered from myelopathy due to atlantoaxial subluxation. All five patients with Down syndrome also had a simultaneous congenital skeletal anomaly, either os odontoideum or ossiculum terminale. Of the five patients with Down syndrome, three had VA anomalies at the CVJ, two had fenestration and one had a persistent first intersegmental artery. Of the other 41 patients without Down syndrome, five had VA anomalies at the CVJ. The incidence of VA anomalies at the CVJ was much higher in patients with Down syndrome than in those without Down syndrome. In planning surgery in patients with Down syndrome with symptomatic atlantoaxial subluxation and a congenital skeletal anomaly at the CVJ, we should consider the possible presence of VA anomalies. Preoperative 3DCTA allows us to precisely identify an anomalous VA and evaluate the possible risk of intraoperative VA injury in advance. (orig.)

  6. CT-based three-dimensional kinematic comparison of dart-throwing motion between wrists with malunited distal radius and contralateral normal wrists

    International Nuclear Information System (INIS)

    Lee, S.; Kim, Y.S.; Park, C.S.; Kim, K.G.; Lee, Y.H.; Gong, H.S.; Lee, H.J.; Baek, G.H.

    2014-01-01

    Aim: To compare motion of the capitate, scaphoid, and lunate in wrists with a malunited distal radius and contralateral normal wrists during dart-throwing motion (DTM) by three-dimensional kinematic studies using computed tomography (CT) images. Materials and methods: CT was performed simultaneously on both wrists in six patients with a unilateral distal radius malunion at three stepwise positions simulating DTM. Using volume registration technique, the kinematic variables of helical axis motion of the capitate, scaphoid, and lunate were calculated and compared between both wrists. The helical motion of the capitate was also evaluated in a scaphoid- and lunate-based coordinate system. Results: Among the average rotation and translation of the scaphoid, lunate, and capitate during DTM, only the average rotation of the capitate was significantly different between the uninjured (88.9°) and the injured (70°) wrist (p = 0.0075). Rotation of the capitate relative to the scaphoid (26.3° versus 37.8°, p = 0.029) or lunate (39.2° versus 59.3°, p = 0.028) was smaller in the malunited wrist. The centres of helical axis motion of the three carpal bones were located more dorsally and radially in the injured wrist. Conclusions: The present study showed that decreased DTM in wrists with a distal radius malunion resulted from decreased midcarpal motion. The present study of the capitate, scaphoid, and lunate in wrists with distal radius malunion might be the first to present a 3D kinematic analysis of the effect of distal radius malunion on the carpal bones

  7. Three-dimensional drip infusion CT cholangiography in patients with suspected obstructive biliary disease: a retrospective analysis of feasibility and adverse reaction to contrast material

    International Nuclear Information System (INIS)

    Persson, A; Dahlström, N; Smedby, Ö; Brismar, TB

    2006-01-01

    Computed Tomography Cholangiography (CTC) is a fast and widely available alternative technique to visualise hepatobiliary disease in patients with an inconclusive ultrasound when MRI cannot be performed. The method has previously been relatively unknown and sparsely used, due to concerns about adverse reactions and about image quality in patients with impaired hepatic function and thus reduced contrast excretion. In this retrospective study, the feasibility and the frequency of adverse reactions of CTC when using a drip infusion scheme based on bilirubin levels were evaluated. The medical records of patients who had undergone upper abdominal spiral CT with subsequent three-dimensional rendering of the biliary tract by means of CTC during seven years were retrospectively reviewed regarding serum bilirubin concentration, adverse reaction and presence of visible contrast media in the bile ducts at CT examination. In total, 153 consecutive examinations in 142 patients were reviewed. Contrast media was observed in the bile ducts at 144 examinations. In 110 examinations, the infusion time had been recorded in the medical records. Among these, 42 examinations had an elevated bilirubin value (>19 umol/L). There were nine patients without contrast excretion; 3 of which had a normal bilirubin value and 6 had an elevated value (25–133 umol/L). Two of the 153 examinations were inconclusive. One subject (0.7%) experienced a minor adverse reaction – a pricking sensation in the face. No other adverse effects were noted. We conclude that drip infusion CTC with an infusion rate of the biliary contrast agent iotroxate governed by the serum bilirubin value is a feasible and safe alternative to MRC in patients with and without impaired biliary excretion. In this retrospective study the feasibility and the frequency of adverse reactions when using a drip infusion scheme based on bilirubin levels has been evaluated

  8. Morphological changes of the internal structure of maxillae with tooth loss. Three-dimensional and mechanical analysis using micro-CT and finite element method

    International Nuclear Information System (INIS)

    Usami, Akinobu; Hara, Toshihiro; Ide, Yoshinobu

    2003-01-01

    The purpose of this study was to analyze the morphological and mechanical properties of the internal structures of maxillae at the molar region using a micro-CT system. Ten dentulous and edentulous maxillae were employed in this study. Images and angle information from all materials were taken by a micro-CT and 100 x 100 x 100 voxels were extracted from the fixed buccal and palatal molar regions in each material for three-dimensional morphological analysis of the internal structure. The bone volume fraction, trabecular thickness, trabecular separation and trabecular number were calculated. To analyze mechanical properties all voxels were converted to micro finite element models with element size of 33 x 33 x 33 μm 3 and maximal stiffness, axial stiffness and angle between the stiffest direction of trabecular and the axial loading direction (angleα) were determined using micro finite element method. In the result, the morphological changes including decrease of bone volume fraction, trabecular thickness and increase of trabecular separation were evident with tooth loss, although trabecular number was not changed. Mechanically, maximal stiffness was decreased with tooth loss at buccal region. However, the axial stiffness at buccal region was larger and the angleα was distributed widely in each edentulous maxilla, comparing to the same region of dentulous maxilla. These findings suggest that trabecular bone become thinner in both buccal and palatal regions, consequently maximal stiffness at buccal region become smaller with tooth loss. On the other hand, axial stiffness at the buccal region in edentulous was larger than one in dentulous. It seems to be caused by the change of the angleα. (author)

  9. Serial CT scannings in herpes simplex encephalitis

    Energy Technology Data Exchange (ETDEWEB)

    Fukushima, M.; Sawada, T.; Kuriyama, Y.; Kinugawa, H.; Yamaguchi, T. (National Cardivascular Center, Osaka (Japan))

    1981-10-01

    Two patients with serologically confirmed herpes simplex encephalitis were studied by serial CT scannings. Case 1, a 60-year-old woman, was admitted to National Cardiovascular Center because of headache, fever, and attacks of Jacksonian seizure. Case 2, a 54-year-old man, was admitted because of fever, consciousness disturbance and right hemiparesis. Pleocytosis (mainly lymphocytes) and elevation of protein content in cerebrospinal fluid were observed in both cases. Both patients presented ''das apallische Syndrom'' one month after admission. The diagnosis of herpes simplex encephalitis was confirmed by typical clinical courses and by greater than fourfold rises in serum antibody titer for herpes simplex virus as well as that in cerebrospinal fluid in case 1. Characteristic CT findings observed in these two cases were summarized as follows: Within a week after the onset, no obvious abnormalities could be detected on CT scans (Case 1). Two weeks after the onset, a large low-density area appeared in the left temporal lobe and in the contralateral insular cortex with midline shift toward the right side (Case 2). One month later, an ill-defined linear and ring-like high-density area (Case 1), or a well-defined high-density area (Case 2), that was enhanced after contrast administration, was observed in the large low-density area in the temporal lobe. These findings were considered as characteristic for hemorrhagic encephalitis. These high-density areas disappeared two months later, however, widespread and intensified low-density areas still remained. In both cases, the basal ganglia and thalamus were completely spared on CT scans. From these observations, it can be concluded that serial CT scannings are quite useful for diagnosis of herpes simplex encephalitis.

  10. Serial CT scannings in herpes simplex encephalitis

    International Nuclear Information System (INIS)

    Fukushima, Masashi; Sawada, Tohru; Kuriyama, Yoshihiro; Kinugawa, Hidekazu; Yamaguchi, Takenori

    1981-01-01

    Two patients with serologically confirmed herpes simplex encephalitis were studied by serial CT scannings. Case 1, a 60-year-old woman, was admitted to National Cardiovascular Center because of headache, fever, and attacks of Jacksonian seizure. Case 2, a 54-year-old man, was admitted because of fever, consciousness disturbance and right hemipare sis. Pleocytosis (mainly lymphocytes) and elevation of protein content in cerebrospinal fluid were observed in both cases. Both patients presented ''das apallische Syndrom'' one month after admission. The diagnosis of herpes simplex encephalitis was confirmed by typical clinical courses and by greater than fourfold rises in serum antibody titer for herpes simplex virus as well as that in cerebrospinal fluid in case 1. Characteristic CT findings observed in these two cases were summarized as follows: Within a week after the onset, no obvious abnormalities could be detected on CT scans (Case 1). Two weeks after the onset, a large low-density area appeared in the left temporal lobe and in the contralateral insular cortex with midline shift toward the right side (Case 2). One month later, an ill-defined linear and ring-like high-density area (Case 1), or a well-defined high-density area (Case 2), that was enhanced after contrast administration, was observed in the large low-density area in the temporal lobe. These findings were considered as characteristic for hemorrhagic encephalitis. These high-density areas disappeared two months later, however, widespread and intensified low-density areas still remained. In both cases, the basal ganglia and thalamus were completely spared on CT scans. From these observations, it can be concluded that serial CT scannings are quite useful for diagnosis of herpes simplex encephalitis. (author)

  11. CT scanning in patients with amputated legs

    International Nuclear Information System (INIS)

    Huebener, K.H.; Ahlemann, L.M.

    1981-01-01

    CT scanning after above-knee amputation and below-knee amputation helps to determine the calcium salt content of the examined bones, and to differentiate changes in the surrounding soft parts. By comaring the sides, it is quite easy to detect osteoporotic changes shortly after amputation which would otherwise remain undetected by X-ray film examination. It is equally easy to verify muscular changes, whereas characteristic changes in density allow to determine the share of vacant fat in muscular atrophy. Initial examinations proved the usefulness of CT diagnosis for early detection of dystrophic osseous and muscular changes and also show the possibilities of early therapy control of dystrophy treatment. (orig.) [de

  12. Eustachian tube three-dimensional reconstruction of secretory otitis media

    International Nuclear Information System (INIS)

    Yu Yafeng; Zhou Weirong; Bao Xueping; Li Min; Hu Zhenmin

    2006-01-01

    Objective: To study relationship between Eustachian tube and secretory otitis media and to explore the pathogeny of secretory otitis by three-dimensional reconstruction of Eustachian tube. Methods: Thirty cases of secretory otitis media (male 19, female 11) were selected randomly. Everyone was checked by otoscope and audiometry. Their bilateral Eustachian tubes were scanning by helix CT while making Valsalva's action. All images were passed on to work station to make three-dimensional reconstruction. Results: Four patients were found have Eustachian tube diseases, while most of patients' Eustachian tubes ventilated normally. Conclusions: Three-dimensional reconstruction of Eustachian tube can open out some pathogens of some secretory otitis medias. It will be helpful to diagnosis and therapy of secretory otitis media. (authors)

  13. Postoperative three-dimensional CT angiography after cerebral aneurysm clipping with titanium clips: detection with single detector CT. Comparison with intra-arterial digital subtraction angiography

    International Nuclear Information System (INIS)

    Sakuma, I.; Tomura, N.; Kinouchi, H.; Takahashi, S.; Otani, T.; Watarai, J.; Mizoi, K.

    2006-01-01

    AIM: To assess the significance of three-dimensional computed tomography angiography (3D-CTA) in detecting remnant necks after cerebral aneurysm clipping. MATERIALS AND METHODS: A total of 59 patients (77 aneurysms) underwent surgery using titanium clips. Two blinded observers independently evaluated the presence of neck remnants on shaded-surface display (SSD) imaging, volume rendered (VR) imaging, and intra-arterial digital subtraction angiography (IADSA). RESULTS: Mean sensitivity and specificity for detecting neck remnants were 50.0 and 74.2% for SSD imaging, 61.5 and 82.8% for VR imaging, and 92.3 and 92.2% for IADSA, respectively. Receiver operating characteristic (ROC) analysis revealed excellent diagnostic performance for IADSA [mean area under ROC curve (Az)=0.97], and good diagnostic performance for 3D-CTA (Az=0.70 and 0.76 for SSD and VR, respectively). Specificity of VR was better than that SSD (p=0.082), however, there was no significant difference between them. CONCLUSION: Use of 3D-CTA techniques can facilitate postoperative evaluation

  14. CT-scanning in otolaryngology, 2

    International Nuclear Information System (INIS)

    Kusakari, Jun; Endo, Satomi; Hara, Akira

    1982-01-01

    Combined computerized tomography-sialography was performed in 28 patients with parotid tumors. Sialography was performed in the usual fashion. After confirming the presence of the contrast material within the parotid gland by X-ray, 4 to 5 scannings were done at the width of 10 mm below Repid's base line. With this procedure, the parotid gland was clearly demonstrated and the location of the tumor was shown as a shadow defect. Although the nature of the tumor, especially whether it was malignant or benign was difficult to predict, the CT-findings regarding the size and location of the tumor were completely coincident with the operative findings in all the cases. Accurate appraisal of the relation between the tumor and the facial nerve was possible in all but two cases. The preoperative information obtained from CT-scanning is extremely useful in the case of parotid tumor surgery. (author)

  15. Ocular volume measured by CT scans

    International Nuclear Information System (INIS)

    Hahn, F.J.; Wei-Kom Chu

    1984-01-01

    Newer CT scans have greatly enhanced oculometric research and made it possible to measure ocular dimensions. With these measurements, ocular volume can be more accurately estimated to understand its relationship with age and sex. One hundred CT orbit scans with presumed normal eyes were used for the data base. The mean values and normal variations of ocular volumes at various ages in both sexes are presented. Rapid growth of the eyeball was noted during the first 24 months of age. It reached its peak between the ages of 18 and 30 years of age, after which there was a reduction. Results may be of help in recognizing eye abnormalities such as microophthalmus and macrophthalmia. (orig.)

  16. Usefulness of three dimensional reconstructive images for thoracic trauma induced fractures

    Energy Technology Data Exchange (ETDEWEB)

    Koh, Kyung Hun; Kim, Dong Hun; Kim, Young Sook; Byun, Joo Nam [Chosun University Hospital, Gwangju (Korea, Republic of)

    2006-09-15

    We wanted to evaluate the usefulness of three-dimensional reconstructive images using multidetector computed tomography (MDCT) for thoracic traumatic patients visiting emergency room. 76 patients with fractures of the 105 patients who visited our emergency room with complaints of thoracic trauma were analyzed retrospectively. All the patients had thoracic MDCT performed and the three-dimensional reconstructive images were taken. The fractures were confirmed by axial CT, the clinical information, whole body bone scanning and the multiplanar reformation images. Plain x-ray images were analyzed by the fractured sites in a blind comparison of two radiologists' readings, and then that finding was compared with the axial CT scans and the three-dimensional reconstructive images. The fracture sites were rib (n 68), sternum (n = 14), clavicle (n = 6), scapula (n = 3), spine (n = 5) and combined fractures (n = 14). Plain x-ray and axial CT scans had a correspondency of 0.555 for the rib fractures. Axial CT scans and the three-dimensional reconstructive images had a correspondency of .952. For sternal fractures, those values were 0.692 and 0.928, respectively. The axial CT scans and three-dimensional reconstructive images showed sensitivities of 94% and 91% for rib and other fractures, respectively, and 93% and 100% for sternal fracture, respectively. Three-dimensional reconstructive image had an especially high sensitivity for the diagnosis of sternal fracture. While evaluating thoracic trauma at the emergency room, the three-dimensional reconstructive image was useful to easily diagnose the extent of fracture and it was very sensitive for detecting sternal fracture.

  17. Usefulness of three dimensional reconstructive images for thoracic trauma induced fractures

    International Nuclear Information System (INIS)

    Koh, Kyung Hun; Kim, Dong Hun; Kim, Young Sook; Byun, Joo Nam

    2006-01-01

    We wanted to evaluate the usefulness of three-dimensional reconstructive images using multidetector computed tomography (MDCT) for thoracic traumatic patients visiting emergency room. 76 patients with fractures of the 105 patients who visited our emergency room with complaints of thoracic trauma were analyzed retrospectively. All the patients had thoracic MDCT performed and the three-dimensional reconstructive images were taken. The fractures were confirmed by axial CT, the clinical information, whole body bone scanning and the multiplanar reformation images. Plain x-ray images were analyzed by the fractured sites in a blind comparison of two radiologists' readings, and then that finding was compared with the axial CT scans and the three-dimensional reconstructive images. The fracture sites were rib (n 68), sternum (n = 14), clavicle (n = 6), scapula (n = 3), spine (n = 5) and combined fractures (n = 14). Plain x-ray and axial CT scans had a correspondency of 0.555 for the rib fractures. Axial CT scans and the three-dimensional reconstructive images had a correspondency of .952. For sternal fractures, those values were 0.692 and 0.928, respectively. The axial CT scans and three-dimensional reconstructive images showed sensitivities of 94% and 91% for rib and other fractures, respectively, and 93% and 100% for sternal fracture, respectively. Three-dimensional reconstructive image had an especially high sensitivity for the diagnosis of sternal fracture. While evaluating thoracic trauma at the emergency room, the three-dimensional reconstructive image was useful to easily diagnose the extent of fracture and it was very sensitive for detecting sternal fracture

  18. The correlation between the paired inspiratory and expiratory three-dimensional quantitative CT and pulmonary function test in chronic obstructive pulmonary disease

    International Nuclear Information System (INIS)

    Sui Xi; Song Wei; Xue Huadan; Song Lan; Yang Liang; Jin Zhengyu

    2013-01-01

    Objective: To investigate the correlation between the paired inspiratory and expiratory quantitative CT and pulmonary function tests (PFTs) in patients with chronic obstructive pulmonary disease (COPD). Methods: A total of 84 patients with COPD were enrolled. For each patient, CT scan was performed in deep inspiration and expiration. Using automatic post-processing software, a three-dimension quantitative measurement was employed to assess the CT parameters of emphysema and air trapping. The correlation between CT and PFT was evaluated by the Spearman rank correlation test and multivariate linear regression analysis. Results: The percent 1 [Perc_1, (-984.28 ± 17.93) HU] and percent 15 [Perc_1_5, (-948.35 ± 22.26) HU] from the CT parameters of emphysema were positively correlated with the forced expiratory volume in 1 second predicted (FEV_1%, 48.69 ± 23, 47), the ratio of forced expiratory volume in 1 second over forced vital capacity [FEV_1/FVC, (45.89 ± 15.36)%, r = 0.45-0.67, P < 0.01], was negatively correlated with the ratio of residual volume to total lung capacity [RV/TLC, (61.32 ± 14.48)%]. The other CT parameters of emphysema index (EI) and the parameters of air trapping, the change in relative lung volume with attenuation values from -860 to -950 HU [RVC_-_8_6_0_-_-_9_5_0, (17.66 ± 22.36)%], the expiration to inspiration ratio of mean lung density (MLD_e_x_/_i_n, 0.93 ± 0.06), the expiration to inspiration ratio of lung volume (LV_e_x_/_i_n, 0.71 ± 0.14) had negative correlations with logFEV_1%, FEV_1/FVC (r = -0.48--0.69, P < 0.01) and positive correlations with RV/TLC (r = 0.41-0.66, P < 0.01). The further univariate linear regressions showed that EI, Perc_1, Pere_1_5, RVC_-_8_6_0_-_-_9_5_0, MLD_e_x_/_i_n, LV_e_x_/_i_n were correlated with the parameters of PFTs (R square values of the regression equation, ranged from 0.27 to 0.66, P < 0.01). After the pairwise combinations of the parameters of emphysema and air trapping, multivariate stepwise

  19. Development of the three dimensional image display program for limited cone beam X-ray CT for dental use (Ortho-CT)

    International Nuclear Information System (INIS)

    Arai, Yoshinori; Hashimoto, Koji; Shinoda, Koji

    2000-01-01

    We have already developed and reported a limited cone beam X-ray CT system for dental use (Ortho-CT). This system has been used clinically since 1997. In this study, we report a 3D surface display program for Ortho-CT which has been newly-developed by the authors. The 3D surface display software has been developed using visual C ++ (Microsoft Co. WA. USA) and a personal computer (Pentium 450MHz Intel Co. CA USA, Windows NT 4.0 Microsoft WA. USA). In this software, the 3D surface images are recorded as AVI files and can be displayed on the personal computer. The 3D images can be rotated and a stepwise change of the threshold voxel value for binary image formation can be automatically used. We have applied these 3D surface images to clinical studies from January 1999 to May 1999 at the Radiology section in our Dental hospital. The images can be displayed very easily in personal computers using AVI files. Thirty-five cases have been reconstructed using 3D surface images in this way. The 3D surface image is useful in the diagnosis of fractures of the mandibular head and impacted teeth. Only teeth are observed when a relative threshold voxel value is set at a high level such as about 0.37. When the threshold is changed to a lower value (about 0.3), we can observe both teeth and the surface of the bone. We have developed a 3D surface display program for personal computers. The images are useful for the diagnosis of the pathosis in the maxillofacial region. (author)

  20. CT Enterography

    Science.gov (United States)

    ... a CT scan can be reformatted in multiple planes, and can even generate three-dimensional images. These ... other medical conditions, and if you have a history of heart disease, asthma, diabetes, kidney disease or ...

  1. Evaluation of the relationship between extremity soft tissue sarcomas and adjacent major vessels using contrast-enhanced multidetector CT and three-dimensional volume-rendered CT angiography - A preliminary study

    International Nuclear Information System (INIS)

    Li, YangKang; Lin, JianBang; Cai, AiQun; Zhou, XiuGuo; Zheng, Yu; Wei, XiaoLong; Cheng, Ying; Liu, GuoRui

    2013-01-01

    Background: Accurate description of the relationship between extremity soft tissue sarcoma and the adjacent major vessels is crucial for successful surgery. In addition to magnetic resonance imaging (MRI) or in patients who cannot undergo MRI, two-dimensional (2D) postcontrast computed tomography (CT) images and three-dimensional (3D) volume-rendered CT angiography may be valuable alternative imaging techniques for preoperative evaluation of extremity sarcomas. Purpose: To preoperatively assess extremity sarcomas using multidetector CT (MDCT), with emphasis on postcontrast MDCT images and 3D volume-rendered MDCT angiography in evaluating the relationship between tumors and adjacent major vessels. Material and Methods: MDCT examinations were performed on 13 patients with non-metastatic extremity sarcomas. Conventional CT images and 3D volume-rendered CT angiography were evaluated, with focus on the relationship between tumors and adjacent major vessels. Kappa consistency statistics were performed with surgery serving as the reference standard. Results: The relationship between sarcomas and adjacent vessels was described as one of three patterns: proximity, adhesion, and encasement. Proximity was seen in five cases on postcontrast CT images or in eight cases on volume-rendered images. Adhesion was seen in three cases on both postcontrast CT images and volume-rendered images. Encasement was seen in five cases on postcontrast CT images or in two cases on volume-rendered images. Compared to surgical results, postcontrast CT images had 100% sensitivity, 83.3% specificity, 87.5% positive predictive value, 100% negative predictive value, and 92.3% accuracy in the detection of vascular invasion (κ = 0.843, P = 0.002). 3D volume-rendered CT angiography had 71.4% sensitivity, 100% specificity, 100% positive predictive value, 75% negative predictive value, and 84.6% accuracy in the detection of vascular invasion (κ = 0.698, P = 0.008). On volume-rendered images, all cases

  2. Three dimensional canonical transformations

    International Nuclear Information System (INIS)

    Tegmen, A.

    2010-01-01

    A generic construction of canonical transformations is given in three-dimensional phase spaces on which Nambu bracket is imposed. First, the canonical transformations are defined as based on cannonade transformations. Second, it is shown that determination of the generating functions and the transformation itself for given generating function is possible by solving correspondent Pfaffian differential equations. Generating functions of type are introduced and all of them are listed. Infinitesimal canonical transformations are also discussed as the complementary subject. Finally, it is shown that decomposition of canonical transformations is also possible in three-dimensional phase spaces as in the usual two-dimensional ones.

  3. Three-dimensional neuroimaging

    International Nuclear Information System (INIS)

    Toga, A.W.

    1990-01-01

    This book reports on new neuroimaging technologies that are revolutionizing the study of the brain be enabling investigators to visualize its structure and entire pattern of functional activity in three dimensions. The book provides a theoretical and practical explanation of the new science of creating three-dimensional computer images of the brain. The coverage includes a review of the technology and methodology of neuroimaging, the instrumentation and procedures, issues of quantification, analytic protocols, and descriptions of neuroimaging systems. Examples are given to illustrate the use of three-dimensional enuroimaging to quantitate spatial measurements, perform analysis of autoradiographic and histological studies, and study the relationship between brain structure and function

  4. CT two-dimensional reformation versus three-dimensional volume rendering with regard to surgical findings in the preoperative assessment of the ossicular chain in chronic suppurative otitis media

    International Nuclear Information System (INIS)

    Guo, Yong; Liu, Yang; Lu, Qiao-hui; Zheng, Kui-hong; Shi, Li-jing; Wang, Qing-jun

    2013-01-01

    Purpose: To assess the role of three-dimensional volume rendering (3DVR) in the preoperative assessment of the ossicular chain in chronic suppurative otitis media (CSOM). Materials and methods: Sixty-six patients with CSOM were included in this prospective study. Temporal bone was scanned with a 128-channel multidetector row CT and the axial data was transferred to the workstation for multiplanar reformation (MPR) and 3DVR reconstructions. Evaluation of the ossicular chain according to a three-point scoring system on two-dimensional reformation (2D) and 3DVR was performed independently by two radiologists. The evaluation results were compared with surgical findings. Results: 2D showed over 89% accuracy in the assessment of segmental absence of the ossicular chain in CSOM, no matter how small the segmental size was. 3DVR was as accurate as 2D for the assessment of segmental absence. However, 3DVR was found to be more accurate than 2D in the evaluation of partial erosion of segments. Conclusion: Both 3DVR and 2D are accurate and reliable for the assessment of the ossicular chain in CSOM. The inclusion of 3DVR images in the imaging protocol improves the accuracy of 2D in detecting ossicular erosion from CSOM

  5. CT two-dimensional reformation versus three-dimensional volume rendering with regard to surgical findings in the preoperative assessment of the ossicular chain in chronic suppurative otitis media

    Energy Technology Data Exchange (ETDEWEB)

    Guo, Yong, E-mail: guoyong27@hotmail.com [Department of Radiology, Navy General Hospital, 6# Fucheng Road, Beijing 100048 (China); Liu, Yang, E-mail: liuyangdoc@sina.com [Department of Otorhinolaryngology, Navy General Hospital, 6# Fucheng Road, Beijing 100048 (China); Lu, Qiao-hui, E-mail: Luqiaohui465@126.com [Department of Radiology, Navy General Hospital, 6# Fucheng Road, Beijing 100048 (China); Zheng, Kui-hong, E-mail: zhengkuihong1971@sina.com [Department of Radiology, Navy General Hospital, 6# Fucheng Road, Beijing 100048 (China); Shi, Li-jing, E-mail: Shilijing2003@yahoo.com.cn [Department of Radiology, Navy General Hospital, 6# Fucheng Road, Beijing 100048 (China); Wang, Qing-jun, E-mail: wangqingjun77@163.com [Department of Radiology, Navy General Hospital, 6# Fucheng Road, Beijing 100048 (China)

    2013-09-15

    Purpose: To assess the role of three-dimensional volume rendering (3DVR) in the preoperative assessment of the ossicular chain in chronic suppurative otitis media (CSOM). Materials and methods: Sixty-six patients with CSOM were included in this prospective study. Temporal bone was scanned with a 128-channel multidetector row CT and the axial data was transferred to the workstation for multiplanar reformation (MPR) and 3DVR reconstructions. Evaluation of the ossicular chain according to a three-point scoring system on two-dimensional reformation (2D) and 3DVR was performed independently by two radiologists. The evaluation results were compared with surgical findings. Results: 2D showed over 89% accuracy in the assessment of segmental absence of the ossicular chain in CSOM, no matter how small the segmental size was. 3DVR was as accurate as 2D for the assessment of segmental absence. However, 3DVR was found to be more accurate than 2D in the evaluation of partial erosion of segments. Conclusion: Both 3DVR and 2D are accurate and reliable for the assessment of the ossicular chain in CSOM. The inclusion of 3DVR images in the imaging protocol improves the accuracy of 2D in detecting ossicular erosion from CSOM.

  6. The use of a wax bite wafer and a double computed tomography scan procedure to obtain a three-dimensional augmented virtual skull model.

    NARCIS (Netherlands)

    Swennen, G.R.J.; Mommaerts, M.Y.; Abeloos, J.V.S.; Clercq, C. De; Lamoral, P.; Neyt, N.; Casselman, J.W.; Schutyser, F.A.C.

    2007-01-01

    A detailed visualization of the interocclusal relationship is essential in a three-dimensional virtual planning setup for orthognathic and facial orthomorphic surgery. The purpose of this study was to introduce and evaluate the use of a wax bite wafer in combination with a double computed tomography

  7. Implementation of dual energy CT scanning

    International Nuclear Information System (INIS)

    Marshall, W.; Hall, E.; Doost-Hoseini, A.; Alvarez, R.; Macovski, A.; Cassel, D.

    1984-01-01

    A prereconstruction method for dual energy (PREDECT) analysis of CT scans is described. In theory, this method can (a) eliminate beam hardening and produce an accuracy comparable with monoenergetic scans and (b) provide the effective atomic number and electron density of any voxel scanned. The implementation proves these statements and eliminates some of the objectionable noise. A phantom was constructed with a cylindrical sleeve-like compartment containing known amounts of high atomic number material simulating a removable skull. Conventional scans, with and without this beam hardener, were done of a water bath containing tubes of high electron and high atomic number material. Dual energy scans were then done for PREDECT. To increase the effective separation of the low and high energy beams by using more appropriate tube filtration, a beam filter changer was fabricated containing erbium, tungsten, aluminum, and steel. Erbium, tungsten, and steel were used at high energy and aluminum, steel, and erbium at low energy for data acquisition. The reconstructions were compared visually and numerically for noise levels with the original steel only filtration. A decrease was found in noise down to approximately one-half the prior level when erbium/aluminum or tungsten/aluminum replaced the steel/steel filter. Erbium and tungsten were equally effective. Steel/erbium and steel/aluminum also significantly reduced image noise. The noise in the photoelectric (P) and Compton (C) images is negatively correlated. At any pixel, if the noise is positive in the P image, it is most probably negative in the C. Using this fact, the noise was reduced by postreconstruction processing

  8. CT SCAN EVALUATION OF PULMONARY NODULE

    Directory of Open Access Journals (Sweden)

    A. Ravi Kumar

    2016-06-01

    Full Text Available BACKGROUND Lung carcinomas are quite commonly diagnosed. Thanks to the ever increasing smokers’ population. Majority of the city dwellers are at a higher risk of having this disease when compared to the village counterparts. The stigma through which the person and the family have to undergo before confirming the diagnosis is enormous. So the radiographic methods of diagnosing the malignancies have to improve. Before confirming the diagnosis, the radiologists, the treating physicians should be somewhat confident about the diagnosis so as to prepare the patients and their relatives for the most probable diagnosis before the confirmatory report. The confirmatory procedures include the PET scan and the Histopathology. Both are time consuming procedures and in an economy like ours, finding a PET scanning centre is rather difficult. So the most probable diagnosis has to be thought of using minimal resource. This study puts in a sincere effort to understand and evaluate the pulmonary nodule when identified by a CT scan. This paper is intended to help the practicing radiologists and also make life easy for a practicing physician to identify correctly the lesions and also help the patients to prevent further progression of the disease. METHODS The study was a cross-sectional study. The sample size of the study consisted of thirty patients. CT scan was done in thirty patients who were identified to have lung nodules either by other mode of radiological studies or first time identified in a CT scan itself. The study was conducted in Fathima Institute of Medical Sciences, Kadapa. The study was conducted from 2014 to 2015. RESULT Non-solid nodules were more in number when compared to the solid nodules. All the non-solid nodules were confirmed to be adenomas. Eighty percent of the nodules which were more than 8 mm in size were confirmed to be malignant. One hundred percent of the spiculated border on CT was confirmed to be malignant. In the present study

  9. Trabecular bone strains around a dental implant and associated micromotions--a micro-CT-based three-dimensional finite element study.

    NARCIS (Netherlands)

    Limbert, G.; Lierde, C. van; Muraru, O.L.; Walboomers, X.F.; Frank, M.; Hansson, S.; Middleton, J.; Jaecques, S.

    2010-01-01

    The first objective of this computational study was to assess the strain magnitude and distribution within the three-dimensional (3D) trabecular bone structure around an osseointegrated dental implant loaded axially. The second objective was to investigate the relative micromotions between the

  10. Three dimensional MEMS supercapacitors

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Wei

    2011-10-15

    The overall objective of this research is to achieve compact supercapacitors with high capacitance, large power density, and long cycle life for using as micro power sources to drive low power devices and sensors. The main shortcoming of supercapacitors as a power source is that its energy density typically is about 1/10 of that of batteries. To achieve compact supercapacitors of large energy density, supercapacitors must be developed with high capacitance and power density which are mainly depended on the effective surface area of the electrodes of the supercapacitors. Many studies have been done to increase the effective surface area by modifying the electrode materials, however, much less investigations are focus on machining the electrodes. In my thesis work, micro- and nano-technologies are applied as technology approaches for machining the electrodes with three dimensional (3D) microstructures. More specific, Micro-electro-mechanical system (MEMS) fabrication process flow, which integrates the key process such as LIGA-like (German acronym for Lithographie, Galvanoformung, Abformung, which mean Lithography, Electroplating and Molding) technology or DRIE (deep reactive ion etching), has been developed to enable innovative designs of 3D MEMS supercapacitors which own the electrodes of significantly increased geometric area. Two types of 3D MEMS supercapcitors, based on LIGA-like and DRIE technology respectively, were designed and successfully created. The LIGA-like based 3D MEMS supercapacitor is with an interdigital 3D structure, and consists of silicon substrate, two electroplated nickel current collectors, two PPy (poly pyrrole) electrodes, and solid state electrolyte. The fabrication process flow developed includes the flowing key processes, SU-8 lithography, nickel electroplating, PPy polymerization and solid state electrolyte coating. Electrochemical tests showed that the single electrode of the supercapacitor has the specific capacitance of 0.058 F cm-2

  11. Full-Body CT Scans - What You Need to Know

    Science.gov (United States)

    ... Procedures Medical Imaging Medical X-ray Imaging Full-Body CT Scans - What You Need to Know Share ... if you are thinking of having a whole-body screening: Whole-body CT screening has not been ...

  12. Microcomputer-based image processing system for CT/MRI scans II

    International Nuclear Information System (INIS)

    Kwok, J.C.K.; Yu, P.K.N.; Cheng, A.Y.S.; Ho, W.C.

    1991-01-01

    This paper reports that a microcomputer-based image processing system is used to digitize and process serial sections of CT/MRI scan and reconstruct three-dimensional images of brain structures and brain lesions. The images grabbed also serve as templates and different vital regions with different risk values are also traced out for 3D reconstruction. A knowledge-based system employing rule-based programming has been built to help identifying brain lesions and to help planning trajectory for operations. The volumes of the lesions are also automatically determined. Such system is very useful for medical skills archival, tumor size monitoring, survival and outcome forecasting, and consistent neurosurgical planning

  13. The sensitivity of computed tomography (CT) scans in detecting trauma: are CT scans reliable enough for courtroom testimony?

    Science.gov (United States)

    Molina, D Kimberley; Nichols, Joanna J; Dimaio, Vincent J M

    2007-09-01

    Rapid and accurate recognition of traumatic injuries is extremely important in emergency room and surgical settings. Emergency departments depend on computed tomography (CT) scans to provide rapid, accurate injury assessment. We conducted an analysis of all traumatic deaths autopsied at the Bexar County Medical Examiner's Office in which perimortem medical imaging (CT scan) was performed to assess the reliability of the CT scan in detecting trauma with sufficient accuracy for courtroom testimony. Cases were included in the study if an autopsy was conducted, a CT scan was performed within 24 hours before death, and there was no surgical intervention. Analysis was performed to assess the correlation between the autopsy and CT scan results. Sensitivity, specificity, positive predictive value, and negative predictive value were defined for the CT scan based on the autopsy results. The sensitivity of the CT scan ranged from 0% for cerebral lacerations, cervical vertebral body fractures, cardiac injury, and hollow viscus injury to 75% for liver injury. This study reveals that CT scans are an inadequate detection tool for forensic pathologists, where a definitive diagnosis is required, because they have a low level of accuracy in detecting traumatic injuries. CT scans may be adequate for clinicians in the emergency room setting, but are inadequate for courtroom testimony. If the evidence of trauma is based solely on CT scan reports, there is a high possibility of erroneous accusations, indictments, and convictions.

  14. Lung nodule detection performance in five observers on computed tomography (CT) with adaptive iterative dose reduction using three-dimensional processing (AIDR 3D) in a Japanese multicenter study: Comparison between ultra-low-dose CT and low-dose CT by receiver-operating characteristic analysis.

    Science.gov (United States)

    Nagatani, Yukihiro; Takahashi, Masashi; Murata, Kiyoshi; Ikeda, Mitsuru; Yamashiro, Tsuneo; Miyara, Tetsuhiro; Koyama, Hisanobu; Koyama, Mitsuhiro; Sato, Yukihisa; Moriya, Hiroshi; Noma, Satoshi; Tomiyama, Noriyuki; Ohno, Yoshiharu; Murayama, Sadayuki

    2015-07-01

    To compare lung nodule detection performance (LNDP) in computed tomography (CT) with adaptive iterative dose reduction using three dimensional processing (AIDR3D) between ultra-low dose CT (ULDCT) and low dose CT (LDCT). This was part of the Area-detector Computed Tomography for the Investigation of Thoracic Diseases (ACTIve) Study, a multicenter research project being conducted in Japan. Institutional Review Board approved this study and informed consent was obtained. Eighty-three subjects (body mass index, 23.3 ± 3.2) underwent chest CT at 6 institutions using identical scanners and protocols. In a single visit, each subject was scanned using different tube currents: 240, 120 and 20 mA (3.52, 1.74 and 0.29 mSv, respectively). Axial CT images with 2-mm thickness/increment were reconstructed using AIDR3D. Standard of reference (SOR) was determined based on CT images at 240 mA by consensus reading of 2 board-certificated radiologists as to the presence of lung nodules with the longest diameter (LD) of more than 3mm. Another 5 radiologists independently assessed and recorded presence/absence of lung nodules and their locations by continuously-distributed rating in CT images at 20 mA (ULDCT) and 120 mA (LDCT). Receiver-operating characteristic (ROC) analysis was used to evaluate LNDP of both methods in total and also in subgroups classified by LD (>4, 6 and 8 mm) and nodular characteristics (solid and ground glass nodules). For SOR, 161 solid and 60 ground glass nodules were identified. No significant difference in LNDP for entire solid nodules was demonstrated between both methods, as area under ROC curve (AUC) was 0.844 ± 0.017 in ULDCT and 0.876 ± 0.026 in LDCT (p=0.057). For ground glass nodules with LD 8mm or more, LNDP was similar between both methods, as AUC 0.899 ± 0.038 in ULDCT and 0.941 ± 0.030 in LDCT. (p=0.144). ULDCT using AIDR3D with an equivalent radiation dose to chest x-ray could have comparable LNDP to LDCT with AIDR3D except for smaller ground

  15. Differential Aging Signals in Abdominal CT Scans.

    Science.gov (United States)

    Orlov, Nikita V; Makrogiannis, Sokratis; Ferrucci, Luigi; Goldberg, Ilya G

    2017-12-01

    Changes in the composition of body tissues are major aging phenotypes, but they have been difficult to study in depth. Here we describe age-related change in abdominal tissues observable in computed tomography (CT) scans. We used pattern recognition and machine learning to detect and quantify these changes in a model-agnostic fashion. CT scans of abdominal L4 sections were obtained from Baltimore Longitudinal Study of Aging (BLSA) participants. Age-related change in the constituent tissues were determined by training machine classifiers to differentiate age groups within male and female strata ("Younger" at 50-70 years old vs "Older" at 80-99 years old). The accuracy achieved by the classifiers in differentiating the age cohorts was used as a surrogate measure of the aging signal in the different tissues. The highest accuracy for discriminating age differences was 0.76 and 0.72 for males and females, respectively. The classification accuracy was 0.79 and 0.71 for adipose tissue, 0.70 and 0.68 for soft tissue, and 0.65 and 0.64 for bone. Using image data from a large sample of well-characterized pool of participants dispersed over a wide age range, we explored age-related differences in gross morphology and texture of abdominal tissues. This technology is advantageous for tracking effects of biological aging and predicting adverse outcomes when compared to the traditional use of specific molecular biomarkers. Application of pattern recognition and machine learning as a tool for analyzing medical images may provide much needed insight into tissue changes occurring with aging and, further, connect these changes with their metabolic and functional consequences. Published by Elsevier Inc.

  16. Three-Dimensional Flows

    CERN Document Server

    Araujo, Vitor; Viana, Marcelo

    2010-01-01

    In this book, the authors present the elements of a general theory for flows on three-dimensional compact boundaryless manifolds, encompassing flows with equilibria accumulated by regular orbits. The book aims to provide a global perspective of this theory and make it easier for the reader to digest the growing literature on this subject. This is not the first book on the subject of dynamical systems, but there are distinct aspects which together make this book unique. Firstly, this book treats mostly continuous time dynamical systems, instead of its discrete counterpart, exhaustively treated

  17. Three dimensional system integration

    CERN Document Server

    Papanikolaou, Antonis; Radojcic, Riko

    2010-01-01

    Three-dimensional (3D) integrated circuit (IC) stacking is the next big step in electronic system integration. It enables packing more functionality, as well as integration of heterogeneous materials, devices, and signals, in the same space (volume). This results in consumer electronics (e.g., mobile, handheld devices) which can run more powerful applications, such as full-length movies and 3D games, with longer battery life. This technology is so promising that it is expected to be a mainstream technology a few years from now, less than 10-15 years from its original conception. To achieve thi

  18. Fabrication of malleable three-dimensional-printed customized bolus using three-dimensional scanner.

    Directory of Open Access Journals (Sweden)

    Jae Won Park

    Full Text Available A three-dimensional (3D-printed customized bolus (3D bolus can be used for radiotherapy application to irregular surfaces. However, bolus fabrication based on computed tomography (CT scans is complicated and also delivers unwanted irradiation. Consequently, we fabricated a bolus using a 3D scanner and evaluated its efficacy. The head of an Alderson Rando phantom was scanned with a 3D scanner. The 3D surface data were exported and reconstructed with Geomagic Design X software. A 3D bolus of 5-mm thickness designed to fit onto the nose was printed with the use of rubber-like printing material, and a radiotherapy plan was developed. We successfully fabricated the customized 3D bolus, and further, a CT simulation indicated an acceptable fit of the 3D bolus to the nose. There was no air gap between the bolus and the phantom surface. The percent depth dose (PDD curve of the phantom with the 3D bolus showed an enhanced surface dose when compared with that of the phantom without the bolus. The PDD of the 3D bolus was comparable with that of a commercial superflab bolus. The radiotherapy plan considering the 3D bolus showed improved target coverage when compared with that without the bolus. Thus, we successfully fabricated a customized 3D bolus for an irregular surface using a 3D scanner instead of a CT scanner.

  19. A comparison between intrastomal 3D ultrasonography, CT scanning and findings at surgery in patients with stomal complaints.

    Science.gov (United States)

    Näsvall, P; Wikner, F; Gunnarsson, U; Rutegård, J; Strigård, K

    2014-10-01

    Since there are no reliable investigative tools for imaging parastomal hernia, new techniques are needed. The aim of this study was to assess the validity of intrastomal three-dimensional ultrasonography (3D) as an alternative to CT scanning for the assessment of stomal complaints. Twenty patients with stomal complaints, indicating surgery, were examined preoperatively with a CT scan in the supine position and 3D intrastomal ultrasonography in the supine and erect positions. Comparison with findings at surgery, considered to be the true state, was made. Both imaging methods, 3D ultrasonography and CT scanning, showed high sensitivity (ultrasound 15/18, CT scan 15/18) and specificity (ultrasound 2/2, CT scan 1/2) when judged by a dedicated radiologist. Corresponding values for interpretation of CT scans in routine clinical practice was for sensitivity 17/18 and for specificity 1/2. 3D ultrasonography has a high validity and is a promising alternative to CT scanning in the supine position to distinguish a bulge from a parastomal hernia.

  20. CT scan for the diagnosis of maxillary sinus carcinoma

    International Nuclear Information System (INIS)

    Kimura, Yo; Kato, Isao; Aoyagi, Masaru; Kikuchi, Akira; Koike, Yoshio; Suzuki, Hachiro.

    1984-01-01

    A comparative study between the conventional radiological examination and the computed tomographical examination for the diagnosis of maxillary sinus carcinoma was done. CT scan has been more appreciated to detect the tumor invasion in the pterygopalatine fossa, orbit, posterior ethmoid sinus and skull base than the conventional examination. CT scan was most usefull for the determination of size and location of the tumor. The prognosis by the stage-grouping was significantly separated by the new classification with CT scan. Therefore, new TNM classification of maxillary sinus carcinoma with CT scan should be taken into account. (author)

  1. Three dimensional visualization of medical images

    International Nuclear Information System (INIS)

    Suto, Yasuzo

    1992-01-01

    Three dimensional visualization is a stereoscopic technique that allows the diagnosis and treatment of complicated anatomy site of the bone and organ. In this article, the current status and technical application of three dimensional visualization are introduced with special reference to X-ray CT and MRI. The surface display technique is the most common for three dimensional visualization, consisting of geometric model, voxel element, and stereographic composition techniques. Recent attention has been paid to display method of the content of the subject called as volume rendering, whereby information on the living body is provided accurately. The application of three dimensional visualization is described in terms of diagnostic imaging and surgical simulation. (N.K.)

  2. Three Dimensional Dirac Semimetals

    Science.gov (United States)

    Zaheer, Saad

    2014-03-01

    Dirac points on the Fermi surface of two dimensional graphene are responsible for its unique electronic behavior. One can ask whether any three dimensional materials support similar pseudorelativistic physics in their bulk electronic spectra. This possibility has been investigated theoretically and is now supported by two successful experimental demonstrations reported during the last year. In this talk, I will summarize the various ways in which Dirac semimetals can be realized in three dimensions with primary focus on a specific theory developed on the basis of representations of crystal spacegroups. A three dimensional Dirac (Weyl) semimetal can appear in the presence (absence) of inversion symmetry by tuning parameters to the phase boundary separating a bulk insulating and a topological insulating phase. More generally, we find that specific rules governing crystal symmetry representations of electrons with spin lead to robust Dirac points at high symmetry points in the Brillouin zone. Combining these rules with microscopic considerations identifies six candidate Dirac semimetals. Another method towards engineering Dirac semimetals involves combining crystal symmetry and band inversion. Several candidate materials have been proposed utilizing this mechanism and one of the candidates has been successfully demonstrated as a Dirac semimetal in two independent experiments. Work carried out in collaboration with: Julia A. Steinberg, Steve M. Young, J.C.Y. Teo, C.L. Kane, E.J. Mele and Andrew M. Rappe.

  3. Ultrafast CT scanning of an oak log for internal defects

    Science.gov (United States)

    Francis G. Wagner; Fred W. Taylor; Douglas S. Ladd; Charles W. McMillin; Fredrick L. Roder

    1989-01-01

    Detecting internal defects in sawlogs and veneer logs with computerized tomographic (CT) scanning is possible, but has been impractical due to the long scanning time required. This research investigated a new scanner able to acquire 34 cross-sectional log scans per second. This scanning rate translates to a linear log feed rate of 85 feet (25.91 m) per minute at one...

  4. Three-dimensional reconstruction of the biliary tract using spiral computed tomography. Three-dimensional cholangiography

    International Nuclear Information System (INIS)

    Gon, Masanori; Ogura, Norihiro; Uetsuji, Shouji; Ueyama, Yasuo

    1995-01-01

    In this study, 310 patients with benign biliary diseases, 20 with gallbladder cancer, and 8 with biliary tract carcinoma underwent spiral CT (SCT) scanning at cholangiography. Depiction rate of the shape of the conjunction site of the gallbladder and biliary tract was 27.5% by conventional intravenous cholangiography (DIC), 92.5% by ERC, and 90.0% by DIC-SCT. Abnormal cystic duct course was admitted in 14.1%. Multiplanar reconstruction by DIC-SCT enabled identification of the common bile duct and intrahepatic bile duct stone. Three-dimensional reconstruction of DIC-SCT was effective in evaluating obstruction of the anastomosis or passing condition of after hepatico-jejunostomy. Two-dimensional SCT images through PTCD tube enabled degree of hepatic invasion in bile duct cancer, and three-dimensional images were useful in grasping the morphology of the bile duct branches near the obstruction site. DIC-SCT is therefore considered a useful procedure as non-invasive examination of bile duct lesions. (S.Y.)

  5. Computerized three-dimensional normal atlas

    International Nuclear Information System (INIS)

    Mano, Isamu; Suto, Yasuzo; Suzuki, Masataka; Iio, Masahiro.

    1990-01-01

    This paper presents our ongoing project in which normal human anatomy and its quantitative data are systematically arranged in a computer. The final product, the Computerized Three-Dimensional Normal Atlas, will be able to supply tomographic images in any direction, 3-D images, and coded information on organs, e.g., anatomical names, CT numbers, and T 1 and T 2 values. (author)

  6. Clinical and CT scan pictures of cerebral cysticercosis

    Energy Technology Data Exchange (ETDEWEB)

    Singounas, E.G.; Krassanakis, K.; Karvounis, P.C. (Evangelismos Hospital, Athens (Greece))

    1982-01-01

    The clinical presentations and CT scan pictures of four patients harbouring big cysticercus cysts are described. The value of CT scanning in detecting these cysts is emphasized, and also the fact that these cysts can behave as space-occyping lesions, which must be differentiated from other cystic formations.

  7. Three-dimensional display improves observer speed and accuracy

    International Nuclear Information System (INIS)

    Nelson, J.A.; Rowberg, A.H.; Kuyper, S.; Choi, H.S.

    1989-01-01

    In an effort to evaluate the potential cost-effectiveness of three-dimensional (3D) display equipment, we compared the speed and accuracy of experienced radiologists identifying in sliced uppercase letters from CT scans with 2D and pseudo-3D display. CT scans of six capital letters were obtained and printed as a 2D display or as a synthesized pseudo-3D display (Pixar). Six observes performed a timed identification task. Radiologists read the 3D display an average of 16 times faster than the 2D, and the average error rate of 2/6 (± 0.6/6) for 2D interpretations was totally eliminated. This degree of improvement in speed and accuracy suggests that the expense of 3D display may be cost-effective in a defined clinical setting

  8. Automatic calibration method of voxel size for cone-beam 3D-CT scanning system

    International Nuclear Information System (INIS)

    Yang Min; Wang Xiaolong; Wei Dongbo; Liu Yipeng; Meng Fanyong; Li Xingdong; Liu Wenli

    2014-01-01

    For a cone-beam three-dimensional computed tomography (3D-CT) scanning system, voxel size is an important indicator to guarantee the accuracy of data analysis and feature measurement based on 3D-CT images. Meanwhile, the voxel size changes with the movement of the rotary stage along X-ray direction. In order to realize the automatic calibration of the voxel size, a new and easily-implemented method is proposed. According to this method, several projections of a spherical phantom are captured at different imaging positions and the corresponding voxel size values are calculated by non-linear least-square fitting. Through these interpolation values, a linear equation is obtained that reflects the relationship between the voxel size and the rotary stage translation distance from its nominal zero position. Finally, the linear equation is imported into the calibration module of the 3D-CT scanning system. When the rotary stage is moving along X-ray direction, the accurate value of the voxel size is dynamically exported. The experimental results prove that this method meets the requirements of the actual CT scanning system, and has virtues of easy implementation and high accuracy. (authors)

  9. Measurements of the frontal and prefrontal lobe volumes by three dimensional magnetic resonance imaging scan. III. Analysis of sex differences with advanced age

    Energy Technology Data Exchange (ETDEWEB)

    Kanemura, Hideaki; Aihara, Masao; Nakazawa, Shinpei [Yamanashi Medical Univ., Tamaho (Japan)

    2002-09-01

    To determine whether there is sex difference in the growth of the frontal and prefrontal lobes, we quantitatively measured the volume of these lobes by three dimensional (3-D) MRI in healthy 12 males (5 months to 39 years) and six females (1 year 11 months to 27 years). The left and right lobes were studied separately. The 3-D MRI data were acquired by the fast spoiled gradient recalled (SPGR) sequence using a 1.5 T MR imager. The frontal and prefrontal lobe volumes were measured by the volume measurement function of the Workstation. In males, the left to right ratio (L/R ratio) of the frontal and prefrontal lobes increased with age. On the contrary, in females, L/R ratio of the frontal and prefrontal lobes showed no significant change with advancing age. These results highlighted sex-specific maturational changes of the frontal and prefrontal lobes and suggested that quantitative data on the frontal and prefrontal lobe are important in interpreting brain abnormalities in children with developmental disorders. (author)

  10. Measurements of the frontal and prefrontal lobe volumes by three dimensional magnetic resonance imaging scan. III. Analysis of sex differences with advanced age

    International Nuclear Information System (INIS)

    Kanemura, Hideaki; Aihara, Masao; Nakazawa, Shinpei

    2002-01-01

    To determine whether there is sex difference in the growth of the frontal and prefrontal lobes, we quantitatively measured the volume of these lobes by three dimensional (3-D) MRI in healthy 12 males (5 months to 39 years) and six females (1 year 11 months to 27 years). The left and right lobes were studied separately. The 3-D MRI data were acquired by the fast spoiled gradient recalled (SPGR) sequence using a 1.5 T MR imager. The frontal and prefrontal lobe volumes were measured by the volume measurement function of the Workstation. In males, the left to right ratio (L/R ratio) of the frontal and prefrontal lobes increased with age. On the contrary, in females, L/R ratio of the frontal and prefrontal lobes showed no significant change with advancing age. These results highlighted sex-specific maturational changes of the frontal and prefrontal lobes and suggested that quantitative data on the frontal and prefrontal lobe are important in interpreting brain abnormalities in children with developmental disorders. (author)

  11. Spinal CT scan, 1. Cervical and thoracic spines

    Energy Technology Data Exchange (ETDEWEB)

    Nakagawa, Hiroshi (Aichi Medical Univ. (Japan))

    1982-01-01

    Methods of CT of the cervical and thoracic spines were explained, and normal CT pictures of them were described. Spinal CT was evaluated in comparison with other methods in various spinal diseases. Plain CT revealed stenosis due to spondylosis or ossification of posterior longitudinal ligament and hernia of intervertebral disc. CT took an important role in the diagnosis of spinal cord tumors with calcification and destruction of the bone. CT scan in combination with other methods was also useful for the diagnosis of spinal injuries, congenital anomalies and infections.

  12. Early appearance of SARS on chest CT scan

    International Nuclear Information System (INIS)

    Cheng Xiaoguang; Feng Suchen; Xia Guoguang; Zhao Tao; Gu Xiang; Qu Hui

    2003-01-01

    Objective: To evaluate the early appearance of SARS on chest CT scan and its role in the early diagnosis. Methods: Forty cases of SARS in keeping with the criteria of the Ministry of Health had chest CT scans within 7 days of onset of symptoms, and CR chest X-ray films were available as well. These chest X-rays and CT images were retrospectively reviewed to determine if there were any abnormalities on the images. The lesions on the chest CT images were then further analyzed in terms of the number, location, size, and density. Results: Positive abnormalities on chest CT scans were revealed in all 40 SARS cases. Positive findings on CR chest films were showed in only 25 cases, equivocal in 6, and normal in 9 cases. The main abnormalities seen on CT and X-rays were pulmonary infiltrations varied markedly in severity. 70 % cases had 1 or 2 lesions on chest CT scan, 30 % cases had 3 or more lesions. The lesions seen on chest CT scan tended to be ground-glass opacification, sometimes with consolidation which was very faint and inhomogeneous, easily missed on chest X-rays. Typically the lesions were located in the periphery of the lung, or both central and peripheral lung, but very rare in a pure central location. They were commonly in the shape of patch or ball. Conclusions: Chest CT scan is much more sensitive in detecting the lesions of the lung in SARS. The early appearance of SARS on chest CT scan is characteristic but non-specific, indicating that chest CT scan plays a very important role in the early diagnosis and differential diagnosis of SARS

  13. Virtual planning of dental implant placement using CT double scan-technique - own experience

    International Nuclear Information System (INIS)

    Wojciechowski, W.; Urbanik, A.; Kownacki, P.; Kownacki, S.

    2007-01-01

    The correctness of CT performed with the use of a double-scan technique is the basis for achieving proper quality of 3D reconstructions of the maxilla or mandible and subsequent virtual planning of dental implant placement. The aim of this study was the presentation of the methodology of computed tomography scanning and own experience with the use of the double-scan technique. The study group included 26 individuals who underwent MDCT with a double-scan technique using a MDCT scanner SOMATOM Sensation (Siemens, Germany). The parameters of the examination: slice-collimation 10 x 0.75 mm, slice-thickness 0.75 mm. The first CT scan in the procedure was the scan of the patient wearing a radiological prosthesis and occlusal index, which was followed by a separate scan of the radiological prosthesis. These two CT scans were copied and transferred to PC with Procera Software program (Nobel Biocare, Sweden) where dental implant placement was virtually planned. In all 26 patients, precise three-dimensional reconstructions of the anatomical structure were obtained. In 11 patients, on the basis of the virtual planning, the implant placement was performed, 5 patients were referred to preparatory procedures, that is, restoration of the alveolar process, otolaryngological treatment of the maxillary sinuses. The remaining 10 patients did not qualify to the procedure because of unfavorable anatomical ideation's. Correct computed tomography with double-scan technique enables virtual planning of dental implant placement, on the basis of which the real procedure of implantation can be performed. (author)

  14. Human vocal tract resonances and the corresponding mode shapes investigated by three-dimensional finite-element modelling based on CT measurement.

    Science.gov (United States)

    Vampola, Tomáš; Horáček, Jaromír; Laukkanen, Anne-Maria; Švec, Jan G

    2015-04-01

    Resonance frequencies of the vocal tract have traditionally been modelled using one-dimensional models. These cannot accurately represent the events in the frequency region of the formant cluster around 2.5-4.5 kHz, however. Here, the vocal tract resonance frequencies and their mode shapes are studied using a three-dimensional finite element model obtained from computed tomography measurements of a subject phonating on vowel [a:]. Instead of the traditional five, up to eight resonance frequencies of the vocal tract were found below the prominent antiresonance around 4.7 kHz. The three extra resonances were found to correspond to modes which were axially asymmetric and involved the piriform sinuses, valleculae, and transverse vibrations in the oral cavity. The results therefore suggest that the phenomenon of speaker's and singer's formant clustering may be more complex than originally thought.

  15. Three dimensional energy profile:

    International Nuclear Information System (INIS)

    Kowsari, Reza; Zerriffi, Hisham

    2011-01-01

    The provision of adequate, reliable, and affordable energy has been considered as a cornerstone of development. More than one-third of the world's population has a very limited access to modern energy services and suffers from its various negative consequences. Researchers have been exploring various dimensions of household energy use in order to design strategies to provide secure access to modern energy services. However, despite more than three decades of effort, our understanding of household energy use patterns is very limited, particularly in the context of rural regions of the developing world. Through this paper, the past and the current trends in the field of energy analysis are investigated. The literature on rural energy and energy transition in developing world has been explored and the factors affecting households' decisions on energy use are listed. The and the factors affecting households' decisions on energy use are listed. The gaps identified in the literature on rural household energy analysis provide a basis for developing an alternative model that can create a more realistic view of household energy use. The three dimensional energy profile is presented as a new conceptual model for assessment of household energy use. This framework acts as a basis for building new theoretical and empirical models of rural household energy use. - Highlights: ► Reviews literature on household energy, energy transitions and decision-making in developing countries. ► Identifies gaps in rural household energy analysis and develops a new conceptual framework. ► The 3-d energy profile provides a holistic view of household energy system characteristics. ► Illustrates the use of the framework for understanding household energy transitions.

  16. Three-dimensional echocardiography

    International Nuclear Information System (INIS)

    Buck, Thomas

    2011-01-01

    Presents tips and tricks for beginners and experts Provides educational material for 3D training courses Features comprehensively illustrated cases Includes an accompanying DVD with video clips of all sample cases Three-dimensional echocardiography is the most recent fundamental advancement in echocardiography. Since real-time 3D echocardiography became commercially available in 2002, it has rapidly been accepted in echo labs worldwide. This book covers all clinically relevant aspects of this fascinating new technology, including a comprehensive explanation of its basic principles, practical aspects of clinical application, and detailed descriptions of specific uses in the broad spectrum of clinically important heart disease. The book was written by a group of well-recognized international experts in the field, who have not only been involved in the scientific and clinical evolution of 3D echocardiography since its inception but are also intensively involved in expert training courses. As a result, the clear focus of this book is on the practical application of 3D echocardiography in daily clinical routine with tips and tricks for both beginners and experts, accompanied by more than 150 case examples comprehensively illustrated in more than 800 images and more than 500 videos provided on a DVD. In addition to an in-depth review of the most recent literature on real-time 3D echocardiography, this book represents an invaluable reference work for beginners and expert users of 3D echocardiography. - Tips and tricks for beginners and experts - Educational material for 3D training courses - Comprehensively illustrated cases - DVD with video clips of all sample cases.

  17. Using Intraoral Scanning Technology for Three-Dimensional Printing of Kennedy Class I Removable Partial Denture Metal Framework: A Clinical Report.

    Science.gov (United States)

    Hu, Feng; Pei, Zhenhua; Wen, Ying

    2017-11-16

    Removable partial dentures (RPDs) are used to restore missing teeth and are traditionally fabricated using the lost-wax casting technique. The casting process is arduous, time-consuming, and requires a skilled technician. The development of intraoral scanning and 3D printing technology has made rapid prototyping of the RPD more achievable. This article reports a completed case of direct fabrication of a maxillary RPD metal framework (Kennedy Class I) using intraoral scanning and 3D printing techniques. Acceptable fit and satisfactory clinical outcome were demonstrated. Intraoral scanning and 3D printing for fabrication of the RPD metal framework is a useful alternative to conventional impression and casting techniques, especially for patients suffering from nasal obstruction or intolerance. © 2017 by the American College of Prosthodontists.

  18. Confidence in Assessment of Lumbar Spondylolysis Using Three-Dimensional Volumetric T2-Weighted MRI Compared With Limited Field of View, Decreased-Dose CT.

    Science.gov (United States)

    Delavan, Joshua Adam; Stence, Nicholas V; Mirsky, David M; Gralla, Jane; Fadell, Michael F

    2016-07-01

    Limited z-axis-coverage computed tomography (CT) to evaluate for pediatric lumbar spondylolysis, altering the technique such that the dose to the patient is comparable or lower than radiographs, is currently used at our institution. The objective of the study was to determine whether volumetric 3-dimensional fast spin echo magnetic resonance imaging (3D MRI) can provide equal or greater diagnostic accuracy compared with limited CT in the diagnosis of pediatric lumbar spondylolysis without ionizing radiation. Volumetric 3D MRI can provide equal or greater diagnostic accuracy compared with low-dose CT for pediatric lumbar spondylolysis without ionizing radiation. Clinical review. Level 2. Three pediatric neuroradiologists evaluated 2-dimensional (2D) MRI, 2D + 3D MRI, and limited CT examinations in 42 pediatric patients who obtained imaging for low back pain and suspected spondylolysis. As there is no gold standard for the diagnosis of spondylolysis besides surgery, interobserver agreement and degree of confidence were compared to determine which modality is preferable. Decreased-dose CT provided a greater level of agreement than 2D MRI and 2D + 3D MRI. The kappa for rater agreement with 2D MRI, 2D + 3D MRI, and CT was 0.19, 0.32, and 1.0, respectively. All raters agreed in 31%, 40%, and 100% of cases with 2D MRI, 2D + 3D MRI, and CT. Lack of confidence was significantly lower with CT (0%) than with 2D MRI (30%) and 2D + 3D MRI (25%). For diagnosing spondylolysis, radiologist agreement and confidence trended toward improvement with the addition of a volumetric 3D MRI sequence to standard 2D MRI sequences compared with 2D MRI alone; however, agreement and confidence remain significantly greater using decreased-dose CT when compared with either MRI acquisition. Decreased-dose CT of the lumbar spine remains the optimal examination to confirm a high suspicion of spondylolysis, with dose essentially equivalent to radiographs. If clinical symptoms are not classic for

  19. Role of CT scan in diagnosis of acute appendicitis

    International Nuclear Information System (INIS)

    Salem, O.A.; Khasawneh, M.

    2007-01-01

    To evaluate the diagnostic accuracy of the spiral-CT in patients with clinically suspected acute appendicitis. A total of 124 patients referred for CT scan with suspected appendicitis between January 2005 and October 2006 were assessed for the appendiceal size and the presence of signs of appendicitis. The findings were correlated with surgical histopathology. CT scan had a sensitivity of 95 percent and a specifity of 93 percent and an overall accuracy of 92 percent. The use of spiral CT in patients with equivocal clinical presentation suspected of having acute appendicitis can lead to significant improvement in the preoperative diagnosis. (author)

  20. Three-dimensional reconstruction of the naupliar musculature and a scanning electron microscopy atlas of nauplius development of Balanus improvisus (Crustacea

    DEFF Research Database (Denmark)

    Semmler, Henrike; Høeg, Jens Thorvald; Scholtz, Gerhard

    2009-01-01

    , as is the setation pattern of the first antennae. The naupliar musculature of B. improvisus was stained with phalloidin to visualise F-actin, followed by analysis using confocal laser scanning microscopy (CLSM) with subsequent application of 3D imaging software. The larval musculature is already fully established......An atlas of the naupliar development of the cirripede Balanus improvisus Darwin, 1854 using scanning electron microscopy (SEM) is provided. Existing spikes on the hindbody increase in number with each moult and are an applicable character for identification of the different nauplius stages...

  1. Computed Tomography (CT) Scans and Cancer

    Science.gov (United States)

    ... Reporting & Auditing Grant Transfer Grant Closeout Contracts & Small Business Training Cancer Training at NCI (Intramural) Resources for ... companies (and Medicare) do not currently reimburse the costs of this procedure. Also, because CT ... the effectiveness of low-dose helical CT for lung cancer ...

  2. Adult Sex Identification Using Three-Dimensional Computed Tomography (3D-CT of the Pelvis: A Study Among a Sample of the Egyptian Population

    Directory of Open Access Journals (Sweden)

    Enas M. A. Mostafa

    2016-06-01

    Full Text Available Sex identification of unknown human skeletal remains is of great importance in establishing identity and individuality. In adults, the hip bone is the most reliable sex indicator because of its sexual dimorphism. Each population should have its own specific standards of identification. The objective of this study is to develop a logistic regression formula for adult sex identification using threedimensional computed tomography (3D-CT of the pelvis and to perform an assessment of its validity in sex determination among a sample of the Egyptian population in the Suez Canal region. 141 pelvic-abdominal CT images (free of any pelvic orthopaedic disorder were included; they were reconstructed to produce 3D-CT pelvic images which were divided into a calibration group (47 male and 47 female and a test group (47 CT images the sex of which was unknown to the observers. Twenty radiometric variables were measured for the calibration group. A logit response formula for sex prediction was developed and applied on the test group for sex prediction. The logit response formula for the test sample showed sensitivity, specificity, and an overall accuracy of 100%. The proposed method represents a quick and reliable metric method in establishing sex from a CT image of the pelvis bone.

  3. Abdominal and Pelvic CT

    Science.gov (United States)

    ... a CT scan can be reformatted in multiple planes, and can even generate three-dimensional images. These ... other medical conditions and whether you have a history of heart disease, asthma, diabetes, kidney disease or ...

  4. Computed Tomography (CT) -- Head

    Medline Plus

    Full Text Available ... a CT scan can be reformatted in multiple planes, and can even generate three-dimensional images. These ... other medical conditions and whether you have a history of heart disease, asthma, diabetes, kidney disease or ...

  5. Computed Tomography (CT) -- Sinuses

    Medline Plus

    Full Text Available ... a CT scan can be reformatted in multiple planes, and can even generate three-dimensional images. These ... other medical conditions and whether you have a history of heart disease, asthma, diabetes, kidney disease or ...

  6. Abdominal and Pelvic CT

    Medline Plus

    Full Text Available ... a CT scan can be reformatted in multiple planes, and can even generate three-dimensional images. These ... other medical conditions and whether you have a history of heart disease, asthma, diabetes, kidney disease or ...

  7. Computed Tomography (CT) -- Sinuses

    Science.gov (United States)

    ... a CT scan can be reformatted in multiple planes, and can even generate three-dimensional images. These ... other medical conditions and whether you have a history of heart disease, asthma, diabetes, kidney disease or ...

  8. Computed Tomography (CT) -- Head

    Science.gov (United States)

    ... a CT scan can be reformatted in multiple planes, and can even generate three-dimensional images. These ... other medical conditions and whether you have a history of heart disease, asthma, diabetes, kidney disease or ...

  9. Diagnosis of gynecologic pelvic masses by CT scans

    International Nuclear Information System (INIS)

    Ito, Hisao; Kubo, Atsushi; Takagi, Yaeko; Kinoshita, Fumio; Maekawa, Akira.

    1981-01-01

    Two hundred eighty four patients with gynecologic pelvic masses were evaluated with CT scans. Of the patients, 196 had subsequent surgical determination of abnormalities and pathological proof of diagnosis was obtained. Only these 196 patients were included in this study. The CT scans could provide correct diagnosis in 113 of 114 (99%) patients with benign uterine tumor and in all (100%) patients with either serous cystadenoma or dermoid cyst. However, evaluation of mucinous cystadenoma (44%) and endometriosis cyst (37%) by CT scan has some limitations. It was difficult to differentiate mucinous cystadenoma from ovarian carcinoma, because both lesions had partial multiloculation and solid-like areas in the cyst. The CT findings of endometriosis cyst had similarity with serous cystadenoma, and 5 of 8 patients with this disease were diagnosed as serous cystadenoma. Ovarian fibroma and endometrial cancer were also not determined by CT scans. CT identified 87% of patients with ovarian cancer, while false positive rate of this disease was 38% (8/21). In 6 of 13 patients with both of leiomyoma and ovarian cyst, CT was able to demonstrate ovarian lesions that were overlooked by bimanual examinations. The role of CT scanning in our clinical practice is discussed. (author)

  10. CT scan findings in focal epilepsy

    International Nuclear Information System (INIS)

    Kobayashi, Eiki; Mihara, Tadahiro; Yamamoto, Kunimitsu; Yamashita, Kenji; Asakura, Tetsuhiko

    1980-01-01

    In 80 cases of focal epilepsy, excluding such cases as late onset after the age of 30 and traumatic or expansive lesions, the epileptogenic foci have been studied by comparing the CT findings with the seizure types and the EEG findings. The results were as follows: (1) Abnormal CT findings were observed in 36% of the patients. (2) These findings were classified into 4 large groups: localized cerebral atrophy, localized low density, localized high density with contrast enhancement and diffuse cerebral atrophy. (3) The incidence of CT abnormality was higher in the cases with continuous and localized EEG abnormality than in the cases with other types of EEG abnormality. In 48% of the cases, the location of the abnormal CT findings coincided with their EEG foci. (4) In the cases of temporal lobe epilepsy without abnormal CT images, the print-out data compared with the bilateral promised temporal regions, before and after contrast enhancement. The EMI-No. of the medial temporal focus increased more than that of the contralateral side in 3 cases out of 4 after contrast-media injection. (5) Moreover, for the purpose of comparing the CT findings on general seizures with those in focal seizures, we have studied 80 cases of general seizures. In the cases of the general seizures, abnormal CT findings were observed in only 16%. These abnormal findings were diffuse in 5 cases, localized in 6 cases, and combined in 3 cases. (author)

  11. Three dimensional imaging of otoliths

    International Nuclear Information System (INIS)

    Barry, B.; Markwitz, A.; David, B.

    2008-01-01

    Otoliths are small structures in fish ears made of calcium carbonate which carry a record of the environment in which the fish live. Traditionally, in order to study their microchemistry by a scanning technique such as PIXE the otoliths have been either ground down by hand or thin sectioned to expose the otolith core. However this technique is subject to human error in judging the core position. In this study we have scanned successive layers of otoliths 50 and 100 μm apart by removing the otolith material in a lapping machine which can be set to a few μm precision. In one study by comparing data from otoliths from the two ears of a freshwater species we found that polishing by hand could miss the core and thus give misleading results as to the life cycle of the fish. In another example we showed detail in a marine species which could be used to build a three dimensional picture of the Sr distribution. (author)

  12. Photon CT scanning of advanced ceramic materials

    International Nuclear Information System (INIS)

    Sawicka, B.D.; Ellingson, W.A.

    1987-02-01

    Advanced ceramic materials are being developed for high temperature applications in advanced heat engines and high temperature heat recovery systems. Small size flaws (10 - 200 μm) and small nonuniformities in density distributions (0.1 -2%) present as long-range density gradients, are critical in most ceramics and their detection is of crucial importance. Computed tomographic (CT) imaging provides a means of obtaining a precise two-dimensional density map of a cross section through an object from which accurate information about small flaws and small density gradients can be obtained. With the use of high energy photon sources high contrast CT images can be obtained for both low and high density ceramics. In the present paper we illustrate the applicability of the photon CT technique to the examination of advanced ceramics. CT images of sintered alumina tiles are presented from which data on high-density inclusions, cracks and density gradients have been extracted

  13. Three-dimensional ICT reconstruction

    International Nuclear Information System (INIS)

    Zhang Aidong; Li Ju; Chen Fa; Sun Lingxia

    2005-01-01

    The three-dimensional ICT reconstruction method is the hot topic of recent ICT technology research. In the context, qualified visual three-dimensional ICT pictures are achieved through multi-piece two-dimensional images accumulation by, combining with thresholding method and linear interpolation. Different direction and different position images of the reconstructed pictures are got by rotation and interception respectively. The convenient and quick method is significantly instructive to more complicated three-dimensional reconstruction of ICT images. (authors)

  14. Three-dimensional ICT reconstruction

    International Nuclear Information System (INIS)

    Zhang Aidong; Li Ju; Chen Fa; Sun Lingxia

    2004-01-01

    The three-dimensional ICT reconstruction method is the hot topic of recent ICT technology research. In the context qualified visual three-dimensional ICT pictures are achieved through multi-piece two-dimensional images accumulation by order, combining with thresholding method and linear interpolation. Different direction and different position images of the reconstructed pictures are got by rotation and interception respectively. The convenient and quick method is significantly instructive to more complicated three-dimensional reconstruction of ICT images. (authors)

  15. CT scan findings in cerebral paragonimiasis

    International Nuclear Information System (INIS)

    Udaka, Fukashi; Okuda, Bungo; Okada, Masako; Okae, Shunji; Kameyama, Masakuni

    1982-01-01

    Computed tomography was performed on 5 patients with chronic cerebral paragonimiasis. CT showed solitary or multiple, amorphous, round, or oval calcifications, and ventricular enlargement in all 5 cases. A large low-density area is also found in 4 of the 5 cases. These CT findings are compatible with previously reported findings of simple X-ray films of the skull, pneumoencephalography, and pathological studies. (author)

  16. Cushing's syndrome with an apparently normal CT scan

    International Nuclear Information System (INIS)

    Vlahos, L.; Strigaris, K.; Aliferopoulos, D.; Pontifex, G.

    1981-01-01

    A case of Cushing's syndrome is described in which the CT scan was considered as normal. The diagnosis was established with selective venography and blood sampling and was verified surgically. (orig.)

  17. Clinical study of retrocaval ureter diagnosed by CT scan

    International Nuclear Information System (INIS)

    Kiriyama, Isao; Hata, Ryosuke; Amemiya, Hiroshi

    1987-01-01

    Although retrocaval ureter is relatively uncommon congenital anomaly, surgical intervention is often necessary to alleviate the clinical signs and symptoms of the patients. Vena cavography has been indispensable imaging modality for the definitive diagnosis of this anomaly. Recently, however, CT scan in addition to excretory urography (IVP) and retrograde pyelography(RP) has been utilized in many reported cases in the diagnosis of retrocaval ureter. We have experienced 3 cases of retrocaval ureter consecutively. In this paper we report these 3 cases of retrocaval ureter, in which CT scan enabled us to confirm the definitive diagnosis. We also report another case of pelviureteric stenosis that was taken for retrocaval ureter by CT scan. Causes of the misdiagnosis is discussed. In conclusion CT scan is useful diagnostic modality in the diagnosis of retrocaval ureter and this lesser invasive technique might lessen the need for vena cavography. (author)

  18. A case study on the historical peninsula of Istanbul based on three-dimensional modeling by using photogrammetry and terrestrial laser scanning.

    Science.gov (United States)

    Ergun, Bahadir; Sahin, Cumhur; Baz, Ibrahim; Ustuntas, Taner

    2010-06-01

    Terrestrial laser scanning is a popular methodology that is used frequently in the process of documenting historical buildings and cultural heritage. The historical peninsula region sprawls over an area of approximately 1,500 ha and is one of the main aggregate areas of the historical buildings in Istanbul. In this study, terrestrial laser scanning and close range photogrammetry techniques are integrated into each other to create a 3D city model of this part of Istanbul, including some of the buildings that represent the most brilliant areas of Byzantine and Ottoman Empires. Several terrestrial laser scanners with their different specifications were used to solve various geometric scanning problems for distinct areas of the subject city. Photogrammetric method was used for the documentation of the façades of these historical buildings for architectural purposes. This study differentiates itself from the similar ones by its application process that focuses on the geometry, the building texture, and density of the study area. Nowadays, the largest-scale studies among 3D modeling studies, in terms of the methodology of measurement, are urban modeling studies. Because of this large scale, the application of 3D urban modeling studies is executed in a gradual way. In this study, a modeling method based on the façades of the streets was used. In addition, the complimentary elements for the process of modeling were combined in several ways. A street model was presented as a sample, as being the subject of the applied study. In our application of 3D modeling, the modeling based on close range photogrammetry and the data of combined calibration with the data of terrestrial laser scanner were used in a compatible way. The final work was formed with the pedestal data for 3D visualization.

  19. Delayed intracerebral hemorrhage as demonstrated by CT scanning

    International Nuclear Information System (INIS)

    Brunetti, J.; Zingesser, L.; Dunn, J.; Rovit, R.L.; Saint Vincent's Hospital and Medical Center, New York

    1979-01-01

    Three patients are presented who developed delayed intracerebral hematomas after head injury. Two patients had essentially negative CT scans on admission and developed intracerebral hematomas within 24 h after injury. They required surgical treatment and had fatal outcomes. The third patient presented with an epidural hematoma on CT scan, developed an intracerebral hematoma 48 h after evacuation of the epidural hematoma, and did well with conservative management. (orig.) [de

  20. Dual scan CT image recovery from truncated projections

    Science.gov (United States)

    Sarkar, Shubhabrata; Wahi, Pankaj; Munshi, Prabhat

    2017-12-01

    There are computerized tomography (CT) scanners available commercially for imaging small objects and they are often categorized as mini-CT X-ray machines. One major limitation of these machines is their inability to scan large objects with good image quality because of the truncation of projection data. An algorithm is proposed in this work which enables such machines to scan large objects while maintaining the quality of the recovered image.

  1. Lung nodule detection performance in five observers on computed tomography (CT) with adaptive iterative dose reduction using three-dimensional processing (AIDR 3D) in a Japanese multicenter study: Comparison between ultra-low-dose CT and low-dose CT by receiver-operating characteristic analysis

    Energy Technology Data Exchange (ETDEWEB)

    Nagatani, Yukihiro, E-mail: yatsushi@belle.shiga-med.ac.jp [Department of Radiology, Shiga University of Medical Science, Otsu 520-2192, Shiga (Japan); Takahashi, Masashi; Murata, Kiyoshi [Department of Radiology, Shiga University of Medical Science, Otsu 520-2192, Shiga (Japan); Ikeda, Mitsuru [Department of Radiological and Medical Laboratory Science, Nagoya University Graduate School of Medicine, Nagoya 461-8673, Aichi (Japan); Yamashiro, Tsuneo [Department of Radiology, Graduate School of Medical Science, University of the Ryukyus, Nishihara 903-0215, Okinawa (Japan); Miyara, Tetsuhiro [Department of Radiology, Graduate School of Medical Science, University of the Ryukyus, Nishihara 903-0215, Okinawa (Japan); Department of Radiology, Okinawa Prefectural Yaeyama Hospital, Ishigaki 907-0022, Okinawa (Japan); Koyama, Hisanobu [Department of Radiology, Kobe University Graduate School of Medicine, Kobe 650-0017, Hyogo (Japan); Koyama, Mitsuhiro [Department of Radiology, Osaka Medical College, Takatsuki 569-8686, Osaka (Japan); Sato, Yukihisa [Department of Radiology, Osaka University Graduate School of Medicine, Suita 565-0871, Osaka (Japan); Department of Radiology, Osaka Medical Center of Cancer and Cardiovascular Diseases, Osaka 537-8511, Osaka (Japan); Moriya, Hiroshi [Department of Radiology, Ohara General Hospital, Fukushima 960-8611 (Japan); Noma, Satoshi [Department of Radiology, Tenri Hospital, Tenri 632-8552, Nara (Japan); Tomiyama, Noriyuki [Department of Radiology, Osaka University Graduate School of Medicine, Suita 565-0871, Osaka (Japan); Ohno, Yoshiharu [Department of Radiology, Kobe University Graduate School of Medicine, Kobe 650-0017, Hyogo (Japan); Murayama, Sadayuki [Department of Radiology, Graduate School of Medical Science, University of the Ryukyus, Nishihara 903-0215, Okinawa (Japan)

    2015-07-15

    Highlights: • Using AIDR 3D, ULDCT showed comparable LND of solid nodules to LDCT. • Using AIDR 3D, LND of smaller GGN in ULDCT was inferior to that in LDCT. • Effective dose in ULDCT was about only twice of that in chest X-ray. • BMI values in study population were mostly in the normal range body habitus. - Abstract: Purpose: To compare lung nodule detection performance (LNDP) in computed tomography (CT) with adaptive iterative dose reduction using three dimensional processing (AIDR3D) between ultra-low dose CT (ULDCT) and low dose CT (LDCT). Materials and methods: This was part of the Area-detector Computed Tomography for the Investigation of Thoracic Diseases (ACTIve) Study, a multicenter research project being conducted in Japan. Institutional Review Board approved this study and informed consent was obtained. Eighty-three subjects (body mass index, 23.3 ± 3.2) underwent chest CT at 6 institutions using identical scanners and protocols. In a single visit, each subject was scanned using different tube currents: 240, 120 and 20 mA (3.52, 1.74 and 0.29 mSv, respectively). Axial CT images with 2-mm thickness/increment were reconstructed using AIDR3D. Standard of reference (SOR) was determined based on CT images at 240 mA by consensus reading of 2 board-certificated radiologists as to the presence of lung nodules with the longest diameter (LD) of more than 3 mm. Another 5 radiologists independently assessed and recorded presence/absence of lung nodules and their locations by continuously-distributed rating in CT images at 20 mA (ULDCT) and 120 mA (LDCT). Receiver-operating characteristic (ROC) analysis was used to evaluate LNDP of both methods in total and also in subgroups classified by LD (>4, 6 and 8 mm) and nodular characteristics (solid and ground glass nodules). Results: For SOR, 161 solid and 60 ground glass nodules were identified. No significant difference in LNDP for entire solid nodules was demonstrated between both methods, as area under ROC

  2. CT study of pancreatic diseases with modified dynamic scanning

    International Nuclear Information System (INIS)

    Qian Minghui; Zhu Guangying

    1990-01-01

    Experience of 20 cases modified dynamic CT scanning is presented. With a slight increased X-ray tube burden, it is possible to investigate tumor blood supply and find small pancreatic insulinoma with this method. The capsular sign typical for chronic traumatic pancreatic hematoma on CT is presented

  3. Dynamic CT scan in cerebral infarction

    International Nuclear Information System (INIS)

    Kobayashi, Shigeki; Oka, Nobuo; Mitsuhashi, Hiromitsu

    1984-01-01

    Forty-two dynamic CT studies were performed on 27 patients with cerebral infarction (11 to 75 years of age), and perfusion patterns of low density areas on plain CT were evaluated. The initial studies were performed 1.5 hours to 60 days after acute onset. The following results were obtained. 1) The perfusion pattern in the low density area on plain CT varies among patients at any periods after onset, ranging from absent perfusion pattern to hyperfusion pattern. No consisitent perfusion pattern was obtained at any given time after onset. 2) Repeat dynamic CT revealed that the perfusion pattern in the low density area changed with time variously. 3) The perfusion pattern or change of perfusion pattern did not correlate with outcome of the patient. 4) At an acute stage, when no abnormal findings were obtained on plain CT, dynamic CT revealed abnormal perfusion pattern, enabling early diagnosis of cerebral infarction and estimation of blood perfusion in the infarcted area. In determining the treatment for the cerebral infarction at an acute stage, it is important to know the condition of the blood perfusion in the infarcted area. For the patients in whom recanalization has already taken place, mannitol or steroid might be effective, providing protection against severe brain edema and hemorrhagic infarction. On the other hand, if recanalization has not taken place, revascularization therapy might be worth trying within 6 hours since the onset. It has been said that ischemic brain damage may not be reversed by the revascularization after 6 hours. Dynamic CT is safe, less invasive, convenient and very useful for early diagnosis of the cerebral infarction and determination of the treatment at the acute stage. (J.P.N.)

  4. Metal artifact reduction of CT scans to improve PET/CT

    NARCIS (Netherlands)

    Van Der Vos, Charlotte S.; Arens, Anne I.J.; Hamill, James J.; Hofmann, Christian; Panin, Vladimir Y.; Meeuwis, Antoi P.W.; Visser, Eric P.; De Geus-Oei, Lioe Fee

    2017-01-01

    In recent years, different metal artifact reduction methods have been developed for CT. These methods have only recently been introduced for PET/CT even though they could be beneficial for interpretation, segmentation, and quantification of the PET/CT images. In this study, phantom and patient scans

  5. Metal Artifact Reduction of CT Scans to Improve PET/CT

    NARCIS (Netherlands)

    Vos, C.S. van der; Arens, A.I.J.; Hamill, J.J.; Hofmann, C.; Panin, V.Y.; Meeuwis, A.P.W.; Visser, E.P.; Geus-Oei, L.F. de

    2017-01-01

    In recent years, different metal artifact reduction methods have been developed for CT. These methods have only recently been introduced for PET/CT even though they could be beneficial for interpretation, segmentation, and quantification of the PET/CT images. In this study, phantom and patient scans

  6. The impact of different cone beam computed tomography and multi-slice computed tomography scan parameters on virtual three-dimensional model accuracy using a highly precise ex vivo evaluation method.

    Science.gov (United States)

    Matta, Ragai-Edward; von Wilmowsky, Cornelius; Neuhuber, Winfried; Lell, Michael; Neukam, Friedrich W; Adler, Werner; Wichmann, Manfred; Bergauer, Bastian

    2016-05-01

    Multi-slice computed tomography (MSCT) and cone beam computed tomography (CBCT) are indispensable imaging techniques in advanced medicine. The possibility of creating virtual and corporal three-dimensional (3D) models enables detailed planning in craniofacial and oral surgery. The objective of this study was to evaluate the impact of different scan protocols for CBCT and MSCT on virtual 3D model accuracy using a software-based evaluation method that excludes human measurement errors. MSCT and CBCT scans with different manufacturers' predefined scan protocols were obtained from a human lower jaw and were superimposed with a master model generated by an optical scan of an industrial noncontact scanner. To determine the accuracy, the mean and standard deviations were calculated, and t-tests were used for comparisons between the different settings. Averaged over 10 repeated X-ray scans per method and 19 measurement points per scan (n = 190), it was found that the MSCT scan protocol 140 kV delivered the most accurate virtual 3D model, with a mean deviation of 0.106 mm compared to the master model. Only the CBCT scans with 0.2-voxel resolution delivered a similar accurate 3D model (mean deviation 0.119 mm). Within the limitations of this study, it was demonstrated that the accuracy of a 3D model of the lower jaw depends on the protocol used for MSCT and CBCT scans. Copyright © 2016 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.

  7. Automated three-dimensional tracking of the left ventricular myocardium in time-resolved and dose-modulated cardiac CT images using deformable image registration.

    Science.gov (United States)

    Gupta, Vikas; Lantz, Jonas; Henriksson, Lilian; Engvall, Jan; Karlsson, Matts; Persson, Anders; Ebbers, Tino

    Assessment of myocardial deformation from time-resolved cardiac computed tomography (4D CT) would augment the already available functional information from such an examination without incurring any additional costs. A deformable image registration (DIR) based approach is proposed to allow fast and automatic myocardial tracking in clinical 4D CT images. Left ventricular myocardial tissue displacement through a cardiac cycle was tracked using a B-spline transformation based DIR. Gradient of such displacements allowed Lagrangian strain estimation with respect to end-diastole in clinical 4D CT data from ten subjects with suspected coronary artery disease. Dice similarity coefficient (DSC), point-to-curve error (PTC), and tracking error were used to assess the tracking accuracy. Wilcoxon signed rank test provided significance of tracking errors. Topology preservation was verified using Jacobian of the deformation. Reliability of estimated strains and torsion (normalized twist angle) was tested in subjects with normal function by comparing them with normal strain in the literature. Comparison with manual tracking showed high accuracy (DSC: 0.99±0.05; PTC: 0.56mm±0.47 mm) and resulted in determinant(Jacobian)>0 for all subjects, indicating preservation of topology. Average radial (0.13 mm), angular (0.64) and longitudinal (0.10 mm) tracking errors for the entire cohort were not significant (p > 0.9). For patients with normal function, average strain [circumferential, radial, longitudinal] and peak torsion estimates were: [-23.5%, 31.1%, -17.2%] and 7.22°, respectively. These estimates were in conformity with the reported normal ranges in the existing literature. Accurate wall deformation tracking and subsequent strain estimation are feasible with the proposed method using only routine time-resolved 3D cardiac CT. Copyright © 2018 Society of Cardiovascular Computed Tomography. Published by Elsevier Inc. All rights reserved.

  8. CT scan findings of fungal pneumonia

    International Nuclear Information System (INIS)

    Heckmann, M.; Uder, M.; Bautz, W.; Heinrich, M.

    2008-01-01

    The importance of fungal infection of the lung in immunocompromised patients has increased substantially during the last decades. Numerically the most patients are those with neutropenia, e.g. patients with malignancies or solid organ and stem cell transplantation, chemotherapy, corticosteroid use and HIV infection. Although fungal infections can occur in immunocompetent patients, their frequency in this population is rare. The clinical symptoms such as fever accompanied with non-productive cough are unspecific. In some patients progression to hypoxemia and dyspnea may occur rapidly. In spite of improved antifungal therapy morbidity and mortality of these infections are still high. Therefore an early and non-invasive diagnosis is very important. That is why CT and even better High-Resolution-CT (HR-CT) is a very important modality in examining immunocompromised patients with a probability of fungal infection. CT is everywhere available and, as a non-invasive method, able to give the relevant diagnose efficiently. This paper should give an overview about the radiologic findings and possible differential diagnosis of diverse pulmonary fungal infections in CT. Pneumonias caused by Aspergillus, Cryptococcus, Candida, Histoplasma, Mucor and Geotrichum capitatum are illustrated. (orig.)

  9. Study on the brain CT scan of SLE patients

    Energy Technology Data Exchange (ETDEWEB)

    Nagaoka, S; Narita, M; Katoh, K; Matsunaga, K; Ishigatsubo, Y [Yokohama City Univ. (Japan). Faculty of Medicine

    1982-03-01

    Cranial CT scanning revealed abnormality in 12 of 25 patients with SLE (48%). Ventricular sulcal enlargement was found mostly in younger patients between 16 and 36 years, an average of 25 years. Abnormality in electroencephalogram, principally paroxysmal abnormality, was found in 8 of 13 cases (62%) of normal CT findings. Non-paroxysmal slow-wave abnormality was observed in 9 of 12 abnormal CT cases. Of 13 patients with CNS symptoms, 8 had abnormal CT findings, and 5 had only mental disorder with normal CT findings. In 12 patients without neuropsychiatric involvement, 4 (33%) had abnormal CT findings. The rate of abnormal CT findings was increased in the patients receiving a high dosage of a steroid agent. Five of 6 patients who showed ventricular sulcal enlargement had been given prednisolone in a dosage of 35 mg or more per day.

  10. Post-operative abdominal CT scanning in extrahepatic biliary atresia

    Energy Technology Data Exchange (ETDEWEB)

    Day, D L; Mulcahy, P F; Letourneau, J G; Dehner, L P

    1989-07-01

    A retrospective review of the abdominal CT scans of 26 children with extrahepatic biliary atresia was performed, and the results were correlated with available surgical and pathologic data. Associated congenital anomalies or acquired abnormalities were identified in these patients. Congenital anomalies included polysplenia, venous anomalies and bowel stenosis. Acquired abnormalities developed secondary to cirrhosis, portal hypertension, intrahepatic biliary duct dilatation, and hepatic ischemia. Despite frequent episodes of ascending cholangitis in these children, no hepatic abscesses were identified by CT or by pathologic examination. In conclusion, abdominal CT scanning of children with extrahepatic biliary atresia can define congenital and acquired abnormalities and provide important anatomic data for the surgeons before liver transplantation. (orig.).

  11. Two-dimensional versus three-dimensional CT angiography in analysis of anatomical suitability for stentgraft repair of abdominal aortic aneurysms

    International Nuclear Information System (INIS)

    Pitoulias, Georgios A.; Aslanidou, Eleni A.; Papadimitriou, Dimitrios K.; Donas, Konstantinos P.; Schulte, Stefan

    2011-01-01

    Background The morphological analysis prior to endovascular abdominal aneurysm repair (EVAR) plays an important role in long-term outcomes. Post-imaging analysis of computed tomographic angiography (CTA) by three-dimensional reconstruction with central lumen line detection (CLL 3D-CTA) enables measurements to be made in orthogonal slices. This might be more precise than equal post-imaging analysis in axial slices by two-dimensional computed tomographic angiography (2D-CTA). Purpose To evaluate the intra- and interobserver variability of CLL 3D-CTA and 2D-CTA post-imaging analysis methods and the agreement between them in pre-EVAR suitability analysis of patients with abdominal aortic aneurysm (AAA). Material and Methods Anonymized CTA data-sets from 70 patients with AAA were analyzed retrospectively. Length measurements included proximal and distal aortic neck lengths and total distance from the lower renal artery to the higher iliac bifurcation. Width measurements included proximal and distal neck diameters, maximum AAA diameter and common iliac diameters just above the iliac bifurcations. The measurements were performed in random order by two vascular surgeons, twice per method with 1-month interval between readings. In the CLL 3D-CTA method we used semi-automated CLL detection by software and manual measurements on CTA slices perpendicular to CLL. The equal measurements in 2D-CTA were performed manually on axial CTA slices using a DICOM viewer workstation. The intra- and interobserver variability, as well as the agreement between the two methods were assessed by Bland-Altman test and bivariate correlation analysis. Results The intraobserver variability was significantly higher in 2D-CTA measurements for both readers. The interobserver variability was significant in 2D-CTA measurements of proximal neck dimensions while the agreement in CLL 3D-CTA analysis between the two readers was excellent in all studied parameters. The agreement between the two suitability

  12. Macrophages and dendritic cells in the rat meninges and choroid plexus: three-dimensional localisation by environmental scanning electron microscopy and confocal microscopy.

    Science.gov (United States)

    McMenamin, Paul G; Wealthall, Rosamund J; Deverall, Marie; Cooper, Stephanie J; Griffin, Brendan

    2003-09-01

    The present investigation provides novel information on the topographical distribution of macrophages and dendritic cells (DCs) in normal meninges and choroid plexus of the rat central nervous system (CNS). Whole-mounts of meninges and choroid plexus of Lewis rats were incubated with various anti-leucocyte monoclonal antibodies and either visualised with gold-conjugated secondary antibody followed by silver enhancement and subsequent examination by environmental scanning electron microscopy or by the use of fluorochromes and confocal microscopy. Large numbers of MHC class II(+) putative DCs were identified on the internal or subarachnoid aspect of dural whole-mounts, on the surface of the cortex (pia/arachnoid) and on the surface of the choroid plexus. Occupation of these sites would allow DCs access to cerebrospinal fluid (CSF) and therefore allow antigens into the subarachnoid space and ventricles. By contrast, macrophages were less evident at sites exposed to CSF and were more frequently located within the connective tissue of the dura/arachnoid and choroid plexus stroma and also in a sub-pial location. The present data suggest that DC may be strategically located within the CNS to sample CSF-borne antigens. Furthermore, the data suggest that CNS tissue samples collected without careful removal of the meninges may inadvertently be contaminated by DCs and meningeal macrophages.

  13. Automatic prostate localization on cone-beam CT scans for high precision image-guided radiotherapy

    International Nuclear Information System (INIS)

    Smitsmans, Monique H.P.; Bois, Josien de; Sonke, Jan-Jakob; Betgen, Anja; Zijp, Lambert J.; Jaffray, David A.; Lebesque, Joos V.; Herk, Marcel van

    2005-01-01

    Purpose: Previously, we developed an automatic three-dimensional gray-value registration (GR) method for fast prostate localization that could be used during online or offline image-guided radiotherapy. The method was tested on conventional computed tomography (CT) scans. In this study, the performance of the algorithm to localize the prostate on cone-beam CT (CBCT) scans acquired on the treatment machine was evaluated. Methods and Materials: Five to 17 CBCT scans of 32 prostate cancer patients (332 scans in total) were used. For 18 patients (190 CBCT scans), the CBCT scans were acquired with a collimated field of view (FOV) (craniocaudal). This procedure improved the image quality considerably. The prostate (i.e., prostate plus seminal vesicles) in each CBCT scan was registered to the prostate in the planning CT scan by automatic 3D gray-value registration (normal GR) starting from a registration on the bony anatomy. When these failed, registrations were repeated with a fixed rotation point locked at the prostate apex (fixed apex GR). Registrations were visually assessed in 3D by one observer with the help of an expansion (by 3.6 mm) of the delineated prostate contours of the planning CT scan. The percentage of successfully registered cases was determined from the combined normal and fixed apex GR assessment results. The error in gray-value registration for both registration methods was determined from the position of one clearly defined calcification in the prostate gland (9 patients, 71 successful registrations). Results: The percentage of successfully registered CBCT scans that were acquired with a collimated FOV was about 10% higher than for CBCT scans that were acquired with an uncollimated FOV. For CBCT scans that were acquired with a collimated FOV, the percentage of successfully registered cases improved from 65%, when only normal GR was applied, to 83% when the results of normal and fixed apex GR were combined. Gray-value registration mainly failed (or

  14. Three-dimensional (3-D) model utilization for fracture reconstruction in oral and maxillofacial surgery: A case report

    Science.gov (United States)

    Damayanti, Ista; Lilies, Latief, Benny S.

    2017-02-01

    Three-dimensional (3-D) printing has been identified as an innovative manufacturing technology of functional parts. The 3-D model was produced based on CT-Scan using Osyrix software, where automatic segmentation was performed and convert into STL format. This STL format was then ready to be produced physically, layer-by-layer to create 3-D model.

  15. Diagnostic value of the coronary CT scan

    International Nuclear Information System (INIS)

    Kiuchi, Sousuke

    1982-01-01

    Using high-resolution computed tomography, coronary scanning has been made to investigate the radiographical details of the middle and inner ear organs. Twenty patients with chronic otitis media, secondary cholesteatoma, sensorineural hearing loss, facial spasm, and suspected meningitis, were evaluated. In 26 of 40 ears in this series, the coronary scans sharply outlined almost all of the bony structures, and showed also the eardrum as a clearly defined soft tissue, but no abnormal radiographical findings were recognized. In the remaining ears with chronic otitis media, the scans were valuable in demonstration of mucosal thickening, granulation tissue, and destruction of the auditory ossicles. (author)

  16. Classication Methods for CT-Scanned Carcass Midsections

    DEFF Research Database (Denmark)

    Skytte, Jacob Lercke; Dahl, Anders Lindbjerg; Larsen, Rasmus

    2011-01-01

    Computed tomography (CT) has successfully been applied in medical environments for decades. In recent years CT has also made its entry to the industrial environments, including the slaughterhouses. In this paper we investigate classication methods for an online CT system, in order to assist...... in the segmentation of the outer fat layer in the mid- section of CT-scanned pig carcasses. Prior information about the carcass composition can potentially be applied for a fully automated solution, in order to optimize the slaughter line. The methods comprise Markov Random Field and contextual Bayesian classication...

  17. Semiautomated hybrid algorithm for estimation of three-dimensional liver surface in CT using dynamic cellular automata and level-sets.

    Science.gov (United States)

    Dakua, Sarada Prasad; Abinahed, Julien; Al-Ansari, Abdulla

    2015-04-01

    Liver segmentation continues to remain a major challenge, largely due to its intense complexity with surrounding anatomical structures (stomach, kidney, and heart), high noise level and lack of contrast in pathological computed tomography (CT) data. We present an approach to reconstructing the liver surface in low contrast CT. The main contributions are: (1) a stochastic resonance-based methodology in discrete cosine transform domain is developed to enhance the contrast of pathological liver images, (2) a new formulation is proposed to prevent the object boundary, resulting from the cellular automata method, from leaking into the surrounding areas of similar intensity, and (3) a level-set method is suggested to generate intermediate segmentation contours from two segmented slices distantly located in a subject sequence. We have tested the algorithm on real datasets obtained from two sources, Hamad General Hospital and medical image computing and computer-assisted interventions grand challenge workshop. Various parameters in the algorithm, such as [Formula: see text], [Formula: see text], [Formula: see text], [Formula: see text], [Formula: see text], [Formula: see text], and [Formula: see text], play imperative roles, thus their values are precisely selected. Both qualitative and quantitative evaluation performed on liver data show promising segmentation accuracy when compared with ground truth data reflecting the potential of the proposed method.

  18. Application of three-dimensional computed tomography in craniofacial clinical practice and research.

    Science.gov (United States)

    Anderson, P J; Yong, R; Surman, T L; Rajion, Z A; Ranjitkar, S

    2014-06-01

    Following the invention of the first computed tomography (CT) scanner in the early 1970s, many innovations in three-dimensional (3D) diagnostic imaging technology have occurred, leading to a wide range of applications in craniofacial clinical practice and research. Three-dimensional image analysis provides superior and more detailed information compared with conventional plain two-dimensional (2D) radiography, with the added benefit of 3D printing for preoperative treatment planning and regenerative therapy. Current state-of-the-art multidetector CT (MDCT), also known as medical CT, has an important role in the diagnosis and management of craniofacial injuries and pathology. Three-dimensional cone beam CT (CBCT), pioneered in the 1990s, is gaining increasing popularity in dental and craniofacial clinical practice because of its faster image acquisition at a lower radiation dose, but sound guidelines are needed to ensure its optimal clinical use. Recent innovations in micro-computed tomography (micro-CT) have revolutionized craniofacial biology research by enabling higher resolution scanning of teeth beyond the capabilities of MDCT and CBCT, presenting new prospects for translational clinical research. Even after four decades of refinement, CT technology continues to advance and broaden the horizons of craniofacial clinical practice and phenomics research. © 2014 Australian Dental Association.

  19. Three dimensional image reconstruction of computed tomograms of the head and neck in the pediatric age group

    International Nuclear Information System (INIS)

    Armstrong, E.A.; Smith, T.H.; Salyer, K.E.

    1985-01-01

    Between August 1983, and April 1984, we have clinically evaluated an experimental computed tomography (CT) software package capable of producing three dimensional (3-D) reconstructed images from axial CT scans. Three dimensional reconstructions have been performed in 115 patient CT examinations for congenital or acquired craniofacial abnormalities, 103 patients; intracranial neoplasms, 6 patients: and the cervical spine and craniocervical junction, 6 patients. Several patients have had studies pre- and postoperatively to plan craniofacial surgery and later evaluate its results on both the bone and soft tissue structures. The results indicate that three dimensional reconstruction using a low dose technique yields information valuable to conceptualize and demonstrate to clinicians the spatial relationships of often complex anatomical relationships in the craniofacial and craniocervical areas [fr

  20. Volumetric measurement of the maxillary sinus by coronal CT scan

    International Nuclear Information System (INIS)

    Ikeda, Atsuko

    1996-01-01

    The volume of the maxillary sinus was estimated by coronal CT scan. The purpose of this study was to compare the estimated volume of the normal maxillary sinus with that of the inflamed maxillary sinus. Patients were classified following evaluation by CT scan of the paranasal sinuses into 3 categories. Group A (n=12): Patients suffered from headache, facial pain and epistaxis, but CT scans of their nasal cavity and paranasal sinus were within normal limits without inflammatory change. Group B (n=69): Patients with bilateral chronic maxillary sinusitis, CT scans of whom showed inflammatory changes in both maxillary sinuses. All of the patients in this group underwent sinus surgery after coronal CT scans. Group C (n=14): Patients with unilateral chronic maxillary sinusitis, CT scans of whom showed inflammatory change in unilateral maxillary sinuses. CT scans of these patients were measured by Plannimeter to take the area of each image of the maxillary sinus. Consecutively imaged areas were summated by integral calculus to obtain an estimate of the sinus volume. The mean maxillary sinus volume in the affected sinuses was significantly smaller than those in the contralateral normal sinuses (p<0.05, Wilcoxon-test). The various volumes of the maxillary sinuses and the developmental cause were discussed. Comparison of groups A with B suggested three distinct patterns; the maxillary sinus volume has decreased due to inflammatory changes in the bone. The small sinuses have a tendency to develop chronic inflammatory change. The aeration in the maxillary sinus may be decreased when anatomic variations that may obstruct the ethmoid infundibulum exist. (K.H.)

  1. Volumetric measurement of the maxillary sinus by coronal CT scan

    Energy Technology Data Exchange (ETDEWEB)

    Ikeda, Atsuko [Tokyo Medical and Dental Univ. (Japan). School of Medicine

    1996-08-01

    The volume of the maxillary sinus was estimated by coronal CT scan. The purpose of this study was to compare the estimated volume of the normal maxillary sinus with that of the inflamed maxillary sinus. Patients were classified following evaluation by CT scan of the paranasal sinuses into 3 categories. Group A (n=12): Patients suffered from headache, facial pain and epistaxis, but CT scans of their nasal cavity and paranasal sinus were within normal limits without inflammatory change. Group B (n=69): Patients with bilateral chronic maxillary sinusitis, CT scans of whom showed inflammatory changes in both maxillary sinuses. All of the patients in this group underwent sinus surgery after coronal CT scans. Group C (n=14): Patients with unilateral chronic maxillary sinusitis, CT scans of whom showed inflammatory change in unilateral maxillary sinuses. CT scans of these patients were measured by Plannimeter to take the area of each image of the maxillary sinus. Consecutively imaged areas were summated by integral calculus to obtain an estimate of the sinus volume. The mean maxillary sinus volume in the affected sinuses was significantly smaller than those in the contralateral normal sinuses (p<0.05, Wilcoxon-test). The various volumes of the maxillary sinuses and the developmental cause were discussed. Comparison of groups A with B suggested three distinct patterns; the maxillary sinus volume has decreased due to inflammatory changes in the bone. The small sinuses have a tendency to develop chronic inflammatory change. The aeration in the maxillary sinus may be decreased when anatomic variations that may obstruct the ethmoid infundibulum exist. (K.H.)

  2. Segmental analysis of cochlea on three-dimensional MR imaging and high-resolution CT. Application to pre-operative assessment of cochlear implant candidates

    International Nuclear Information System (INIS)

    Akiba, Hidenari; Himi, Tetsuo; Hareyama, Masato

    2002-01-01

    High-resolution computed tomography (HRCT) and magnetic resonance imaging (MRI) have recently become standard pre-operative examinations for cochlear implant candidates. HRCT can demonstrate ossification and narrowing of the cochlea, but subtle calcification or soft tissue obstruction may not be detected by this method alone, and so conventional T2 weighted image (T2WI) on MRI has been recommended to disclose them. In this study, segmental analyses of the cochlea were made on three-dimensional MRI (3DMRI) and HRCT in order to predict cochlear implant difficulties. The study involved 59 consecutive patients with bilateral profound sensorineural hearing loss who underwent MRI and HRCT from November 1992 to February 1998. Etiologies of deafness were meningogenic labyrinthitis (n=9), tympanogenic labyrinthitis (n=12), and others (n=38). Pulse sequence of heavy T2WI was steady state free precession and 3DMRI was reconstructed by maximum intensity projection method. HRCT was reconstructed by bone algorithm focusing on the temporal bone. For alternative segmental analysis, cochleas were anatomically divided into five parts and each of them was classified by three ranks of score depending on 3DMRI or HRCT findings. There was a close correlation by ranks between the total score of the five parts on 3DMRI and HRCT (rs=0.86, P<0.001), and a statistically significant difference was identified between causes of deafness in the total score on 3DMRI or HRCT (P<0.001, respectively). There was a significant difference in the score among the five parts on each examination (P<0.001, respectively), and abnormal findings were more frequent in the inferior horizontal part (IHP) of the basal turn. Of the 35 patients who underwent cochlear implantation, no one had ossification in the IHP on HRCT and only one patient had an obstacle to implantation. When no signal void in the IHP on 3DMRI and no ossification in the IHP on HRCT were assumed to be the criteria for candidacy for cochlear

  3. Three-dimensional volumetric assessment of response to treatment

    International Nuclear Information System (INIS)

    Willett, C.G.; Stracher, M.A.; Linggood, R.M.; Leong, J.C.; Skates, S.J.; Miketic, L.M.; Kushner, D.C.; Jacobson, J.O.

    1988-01-01

    From 1981 to 1986, 12 patients with Stage I and II diffuse large cell lymphoma of the mediastinum were treated with 4 or more cycles of multiagent chemotherapy and for nine patients this was followed by mediastinal irradiation. The response to treatment was assessed by three-dimensional volumetric analysis utilizing thoracic CT scans. The initial mean tumor volume of the five patients relapsing was 540 ml in contrast to an initial mean tumor volume of 360 ml for the seven patients remaining in remission. Of the eight patients in whom mediastinal lymphoma volumes could be assessed 1-2 months after chemotherapy prior to mediastinal irradiation, the three patients who have relapsed had volumes of 292, 92 and 50 ml (mean volume 145 ml) in contrast to five patients who have remained in remission with residual volume abnormalities of 4-87 ml (mean volume 32 ml). Four patients in prolonged remission with CT scans taken one year after treatment have been noted to have mediastinal tumor volumes of 0-28 ml with a mean value of 10 ml. This volumetric technique to assess the extent of mediastinal large cell lymphoma from thoracic CT scans appears to be a useful method to quantitate the amount of disease at presentation as well as objectively monitor response to treatment. 13 refs.; 2 figs.; 1 table

  4. Three-dimensional digitizer (neuronavigator): new equipment for computed tomography-guided stereotaxic surgery.

    Science.gov (United States)

    Watanabe, E; Watanabe, T; Manaka, S; Mayanagi, Y; Takakura, K

    1987-06-01

    A new device was invented as an adjunct for computed tomography (CT)-guided stereotaxic or open neurosurgery. It is composed of a multijoint three-dimensional digitizer (sensor arm) and a microcomputer, which indicates the place of the sensor arm tip on preoperative CT images. Computed tomography scan is performed preoperatively with three markers placed on the nasion and ears. At surgery, after fixing the patient's head and the sensor arm, sampling of the standard points was done to translate the position of the tip of the sensor arm onto the CT images displayed on a computer screen. In this way positional data from conventional preoperative CT scan can be directly transferred into the surgical field. This system has the unique feature of introducing CT-guided stereotaxis into conventional open neurosurgery.

  5. Three-dimensional conformal radiotherapy by delineations on CT-based simulation in different respiratory phases for the treatment of senile patients with non-small cell lung cancer.

    Science.gov (United States)

    Wang, Weifeng; Yuan, Feng; Wang, Guoping; Lin, Zhiren; Pan, Yanling; Chen, Longhua

    2015-01-01

    This study aimed to evaluate the application of three-dimensional conformal radiotherapy (3D-CRT) for elderly patients with non-small cell lung cancer (NSCLC) based on computed tomography (CT) simulations in different respiratory phases. A total of 64 patients aged >70 years old with NSCLC were treated by 3D-CRT using CT images in different respiratory phases. The gross tumor volumes (GTVs) at the end of inspiration and end of expiration were combined to obtain the total GTV, which was close to the motional range of tumors during respiration, and no additional expansion of the clinical target volume (CTAV) to planning target volume (PTV) (CTAV:PTV) was included during the recording of respiratory movements. Patients were also planned according to the classic 3D-CRT approach. Efficacy, prognostic factors, and side effects were evaluated. Compared with the classic approach, the average PTV was 18.9% lower (median: 17.3%), and the average lung volume receiving a prescribed dose for a tumor was 22.4% lower (median: 20.9%). The 1-, 2-, and 3-year survival rates were 70.6%, 54.9%, and 29.4%, respectively, with an overall tumor response rate of 79.7%. The Karnofsky performance status and N stage were independent prognostic factors, whereas age was not. Without affecting therapeutic effects, CT simulations in different respiratory phases were well-tolerated in elderly patients with NSCLC, could effectively reduce PTV, and could improve the quality of life.

  6. Comparison of CT scanning and radionuclide imaging in liver disease

    International Nuclear Information System (INIS)

    Friedman, M.L.; Esposito, F.S.

    1980-01-01

    Early experience with body CT suggested its usefulness in many diagnostic problems; jaundice, renal and pancreatic masses, and in the evaluation of relatively inaccessible parts of the body, such as the retroperitineum, mediastinum, and pelvis. Investigation of hepatic disease by CT was not unexpectedly compared to radionuclide liver scanning, the major preexisting modality for imaging the liver. In the evaluation of the jaundiced patient, CT rapidly assumed a major role, providing more specific information about the liver than the RN liver scan, as well as demonstrating adjacent organs. CT differentiate obstructive from non-obstructive jaundice. With respect to mass lesions of the liver, the RN liver scan is more sensitive than CT but less specific. The abnormalities on an isotope image of the liver consist of normal variants in configuration, extrinsic compression by adjacent structures, cysts, hemangiomata, abscesses, and neoplasms. These suspected lesions may then be better delineated by the CT image, and a more precise diagnosis made. The physiologic information provided by the RN liver scan is an added facet which is helpful in the patient with diffuse hepatic disease. The CT image will be normal in many of these patients, however, hemochromatosis and fatty infiltration lend themselves especially to density evaluation by CT. The evaluation of lymphoma is more thorough with CT. Structures other than the liver, such as lymph nodes, are visualized. Gallium, however, provides additional isotopic information in patients with lymphoma, and in addition, is known to be useful in the investigation of a febrile patient with an abscess. Newer isotopic agents expand hepatic imaging in other directions, visualizing the biliary tree and evaluating the jaundiced patient

  7. CT-scanning of ancient Greenlandic Inuit temporal bones

    International Nuclear Information System (INIS)

    Homoe, P.; Videbaek, H.

    1992-01-01

    Additional morphological evidence of former infectious middle ear disease (IMED) was found by CT-scanning in 5 of 6 Greenlandic Inuit crania strongly suspected for former IMED due to earlier examination revealing either bilateral hypocellularity or asymmetry of the pneumatized area of the temporal bones. The CT-scans showed sclerosing and obliteration of the air cells and even destruction of the cellular septae, and a high degree of irregularity of the cells. Sclerosing of the surrounding bone tissue was also found. The findings in one cranium were dubious and could both be regarded as a congenital malformation or an infection in infanthood. CT-scan confirms and even adds to the results of conventional X-ray of temporal bones making hypotheses of paleopathology more reliable. The findings also support the environmental theory of pneumatization of the air cell system in the temporal bones. (13 refs., 10 figs.)

  8. CT-scanning of ancient Greenlandic Inuit temporal bones

    Energy Technology Data Exchange (ETDEWEB)

    Homoe, P [Copenhagen Univ. (Denmark). Lab. of Biological Anthropology and Dept. of Otolaryngology, Head and Neck Surgery; Lynnerup, N [Copenhagen Univ., Lab. of Biological Anthropology and Univ. Inst. of Ferensic Medicine, Copenhagen (Denmark); Videbaek, H [Hvidovre Univ. Hospital, Copenhagen (Denmark). Dept. of Radiology

    1992-01-01

    Additional morphological evidence of former infectious middle ear disease (IMED) was found by CT-scanning in 5 of 6 Greenlandic Inuit crania strongly suspected for former IMED due to earlier examination revealing either bilateral hypocellularity or asymmetry of the pneumatized area of the temporal bones. The CT-scans showed sclerosing and obliteration of the air cells and even destruction of the cellular septae, and a high degree of irregularity of the cells. Sclerosing of the surrounding bone tissue was also found. The findings in one cranium were dubious and could both be regarded as a congenital malformation or an infection in infanthood. CT-scan confirms and even adds to the results of conventional X-ray of temporal bones making hypotheses of paleopathology more reliable. The findings also support the environmental theory of pneumatization of the air cell system in the temporal bones. (13 refs., 10 figs.).

  9. Automated image quality assessment for chest CT scans.

    Science.gov (United States)

    Reeves, Anthony P; Xie, Yiting; Liu, Shuang

    2018-02-01

    Medical image quality needs to be maintained at standards sufficient for effective clinical reading. Automated computer analytic methods may be applied to medical images for quality assessment. For chest CT scans in a lung cancer screening context, an automated quality assessment method is presented that characterizes image noise and image intensity calibration. This is achieved by image measurements in three automatically segmented homogeneous regions of the scan: external air, trachea lumen air, and descending aorta blood. Profiles of CT scanner behavior are also computed. The method has been evaluated on both phantom and real low-dose chest CT scans and results show that repeatable noise and calibration measures may be realized by automated computer algorithms. Noise and calibration profiles show relevant differences between different scanners and protocols. Automated image quality assessment may be useful for quality control for lung cancer screening and may enable performance improvements to automated computer analysis methods. © 2017 American Association of Physicists in Medicine.

  10. Value of CT scan in synovial diseases

    International Nuclear Information System (INIS)

    Tamisier, J.N.; Regent, D.; Thomas, P.; Pere, P.; Gaucher, A.; Capesius, P.

    1986-01-01

    The authors have developed a technique of CT arthroscan which, by the use of a gas or opaque contrast medium, is able to demonstrate the synovial structures of the knee, the shoulder and the hip. Among the essential indications, they include the demonstration of neoplasia of the synovium and the evaluation of the pannus in rheumatoid arthritis. Their secondary indications include the demonstration of fluid effusions in the hip, the precise evaluation of hyperostotic lesions in the same joint, the detection of ossification phenomena in the capsule of the inter-apophyseal joints in ankylosing spondylitis and, in some cases, following negative or doubtful arthrography for the detection of synovial plica. They also recall the usefulness or the arthroscan in the diagnosis of lesions of the labrum glenoidale [fr

  11. Value of CT scan in synovial diseases

    Energy Technology Data Exchange (ETDEWEB)

    Tamisier, J.N.; Regent, D.; Thomas, P.; Pere, P.; Gaucher, A.; Capesius, P.

    1986-02-01

    The authors have developed a technique of CT arthroscan which, by the use of a gas or opaque contrast medium, is able to demonstrate the synovial structures of the knee, the shoulder and the hip. Among the essential indications, they include the demonstration of neoplasia of the synovium and the evaluation of the pannus in rheumatoid arthritis. Their secondary indications include the demonstration of fluid effusions in the hip, the precise evaluation of hyperostotic lesions in the same joint, the detection of ossification phenomena in the capsule of the inter-apophyseal joints in ankylosing spondylitis and, in some cases, following negative or doubtful arthrography for the detection of synovial plica. They also recall the usefulness or the arthroscan in the diagnosis of lesions of the labrum glenoidale.

  12. Diagnosis of pituitary adenoma by dynamic CT scanning

    International Nuclear Information System (INIS)

    Tanabe, Sumiyoshi; Uede, Teiji; Daibo, Masahiko; Niwa, Jun; Hashi, Kazuo

    1988-01-01

    The advantage of high resolution CT in the diagnosis of pituitary microadenomas has been established, but the diagnosis becomes more difficult when the pituitary microadenoma is less than 5 mm in diameter. We have studied the usefulness of dynamic CT scans particularly for diagnosis of small microadenomas. The dynamic CT scans were performed for 61 normal pituitary glands and 68 pituitary adenomas (36 microadenomas, 32 macroadenomas) with a GECT/T 9800 scanner. Coronal sections of 1.5 mm thickness were taken at the plane just in front of the pituitary stalk of the pituitary gland. Following a bolus intra-venous injection of 40 - 60 ml of contrast media using an automatic injector, ten consecutive CT scans of 2 seconds scan time were obtained, beginning 2 seconds from the start of intravenous injection. The first seven scans were taken with an interval of 2.3 seconds, and the last three scans with an interval of 10 seconds. Then, time-density curves were obtained at the ROI which were set on the anterior pituitary gland, the vascular bed of the pituitary gland, the pituitary stalk and the area of the pituitary adenoma respectively. In a normal pituitary gland, the density increases gradually and makes an S shaped curve, then attains the maximum density value (92.3 CT number) approximately 60 seconds after the administration of contrast media. The pituitary vascular bed is located in midline on the upper surface of the pituitary gland, and shows a symmetrical square, triangular or rhomboid shape. In case of pituitary adenoma, the time-density curve makes a plateau curve and attains the maximum density value (60.1 CT number) approximately 60 seconds after the administration of contrast media. In microadenoma, the pituitary vascular bed is either deformed or compressed, showing an asymmetrical shape. (author)

  13. Children's (Pediatric) CT (Computed Tomography)

    Medline Plus

    Full Text Available ... a CT scan can be reformatted in multiple planes, and can even generate three-dimensional images. These ... child may have, and if there is a history of heart disease, asthma, diabetes, kidney disease or ...

  14. Children's (Pediatric) CT (Computed Tomography)

    Science.gov (United States)

    ... a CT scan can be reformatted in multiple planes, and can even generate three-dimensional images. These ... child may have, and if there is a history of heart disease, asthma, diabetes, kidney disease or ...

  15. Three dimensional imaging in cardiac nuclear medicine

    International Nuclear Information System (INIS)

    Torizuka, Kanji; Ishii, Yasushi; Yonekura, Yoshiharu; Yamamoto, Kazutaka; Tamaki, Takeyoshi

    1981-01-01

    Methods to obtain three dimensional images of the heart were reviewed. Gated three dimensional display reconstructed from images using bidirectional collimator, was a useful method to detect akinesis of the heart wall. Tomographic observation of the heart can be carried out by a pinhole collimator to image ischemia with high sensitivity. However the focusing plane must be carefully selected to prevent false positives. In the case of emission CT (ECT), utilization of positron emitters gave a quantitative image without correction, whereas single photon ECT needed the correction due to the absorption of γ-ray. Though the reliability of the images by ECT was high, the time required for data acquisition was much longer than that by a 7 pinhole or bidirectional collimator. (Nakanishi, T.)

  16. MRI of patients with cerebral palsy and normal CT scan

    International Nuclear Information System (INIS)

    Bogaert, P. van; Szliwowski, H.B.

    1992-01-01

    Three children with clinical evidence of cerebral palsy (CP) and normal cerebral computed tomography (CT) scans were evaluated by magnetic resonance imaging (MRI) to identify CT-undetectable white matter lesions in the watershed zones of arterial territories. The two patients with spastic diplegia showed bilateral lesions either in the subcortical regions or in the occipital periventricular regions. The patient with congenital hemiplegia exhibited unilateral lesions in the periventricular region. We conclude that MRI is more informative than CT for the evaluation of patients with CP. (orig.)

  17. MRI of patients with cerebral palsy and normal CT scan

    Energy Technology Data Exchange (ETDEWEB)

    Bogaert, P. van; Szliwowski, H.B. (Hopital Erasme, Brussels (Belgium). Dept. of Neurology); Baleriaux, D.; Christophe, C. (Hopital Erasme, Brussels (Belgium). Dept. of Radiology (Neuroradiology))

    1992-02-01

    Three children with clinical evidence of cerebral palsy (CP) and normal cerebral computed tomography (CT) scans were evaluated by magnetic resonance imaging (MRI) to identify CT-undetectable white matter lesions in the watershed zones of arterial territories. The two patients with spastic diplegia showed bilateral lesions either in the subcortical regions or in the occipital periventricular regions. The patient with congenital hemiplegia exhibited unilateral lesions in the periventricular region. We conclude that MRI is more informative than CT for the evaluation of patients with CP. (orig.).

  18. Analysis of cranial CT-scan findings in cerebral palsy

    International Nuclear Information System (INIS)

    Wada, Fumio; Andoh, Tadashi; Une, Koji; Takamatsu, Tsurukichi

    1981-01-01

    CT-scan findings of 87 cerebral palsied children were studied. They consist of 23 cases of spastic quadriplegia, 9 cases of diplegia, 12 cases of paraplegia, 24 cases of athetosis and mixed type, and 19 cases of hemiplegia. In the former four types, ventricular dilatation and cortical atrophy were measured and abnormal changes in cerebral substance and cerebellar atrophy were observed. Spastic quadriplegia showed most intense changes in every aspect of the abnormalities, while paraplegia had almost normal appearance. Athetosis and mixed type had moderate changes. Hemiplegia always showed asymmetrical view on CT-scan, dilatation of lateral ventricle or atrophy of hemisphere in contralateral side being observed. (author)

  19. Analysis of cranial CT-scan findings in cerebral palsy

    Energy Technology Data Exchange (ETDEWEB)

    Wada, F.; Andoh, T.; Une, K.; Takamatsu, T. (Kitakyushu Municipal Sogo-Ryoiku Center (Japan))

    1981-06-01

    CT-scan findings of 87 cerebral palsied children were studied. They consist of 23 cases of spastic quadriplegia, 9 cases of diplegia, 12 cases of paraplegia, 24 cases of athetosis and mixed type, and 19 cases of hemiplegia. In the former four types, ventricular dilatation and cortical atrophy were measured and abnormal changes in cerebral substance and cerebellar atrophy were observed. Spastic quadriplegia showed most intense changes in every aspect of the abnormalities, while paraplegia had almost normal appearance. Athetosis and mixed type had moderate changes. Hemiplegia always showed asymmetrical view on CT-scan, dilatation of lateral ventricle or atrophy of hemisphere in contralateral side being observed.

  20. The pictures of CT scan of gold pneumonitis

    International Nuclear Information System (INIS)

    Taguchi, Yoshio; Iwata, Takekuni; Kuroda, Yasumasa; Sadato, Norihiro; Tanemoto, Kiichiro; Adachi, Kazuhiko.

    1987-01-01

    We experienced two cases of gold pneumonitis and their interesting findings of CT scan. After the cessation of gold salt, both cases were treated with the corticosteroid, resulting in the disappearance of pulmonary manifestations and clearing of shadows on chest roentgenograms. The findings of CT scan on both cases were very interesting. They were the high density shadows along the bronchovascular bundles, the fluffy figures surroundings these shadows and band like shadows reached to the thoracic wall. We considered that each shadows were pathologically compatible with severe exudative changes of interstitial pneumonitis, shrinkage surroundings them and thickness of interlobular septum. (author)

  1. Three-dimensional assessment of unilateral subcondylar fracture using computed tomography after open reduction

    Directory of Open Access Journals (Sweden)

    Sathya Kumar Devireddy

    2014-01-01

    Full Text Available Objective: The aim was to assess the accuracy of three-dimensional anatomical reductions achieved by open method of treatment in cases of displaced unilateral mandibular subcondylar fractures using preoperative (pre op and postoperative (post op computed tomography (CT scans. Materials and Methods: In this prospective study, 10 patients with unilateral sub condylar fractures confirmed by an orthopantomogram were included. A pre op and post op CT after 1 week of surgical procedure was taken in axial, coronal and sagittal plane along with three-dimensional reconstruction. Standard anatomical parameters, which undergo changes due to fractures of the mandibular condyle were measured in pre and post op CT scans in three planes and statistically analysed for the accuracy of the reduction comparing the following variables: (a Pre op fractured and nonfractured side (b post op fractured and nonfractured side (c pre op fractured and post op fractured side. P < 0.05 was considered as significant. Results: Three-dimensional anatomical reduction was possible in 9 out of 10 cases (90%. The statistical analysis of each parameter in three variables revealed (P < 0.05 that there was a gross change in the dimensions of the parameters obtained in pre op fractured and nonfractured side. When these parameters were assessed in post op CT for the three variables there was no statistical difference between the post op fractured side and non fractured side. The same parameters were analysed for the three variables in pre op fractured and post op fractured side and found significant statistical difference suggesting a considerable change in the dimensions of the fractured side post operatively. Conclusion: The statistical and clinical results in our study emphasised that it is possible to fix the condyle in three-dimensional anatomical positions with open method of treatment and avoid post op degenerative joint changes. CT is the ideal imaging tool and should be used on

  2. CT scan imaging in cervical infections

    International Nuclear Information System (INIS)

    Marsot-Dupuch, K.; Janklewicz, Ph.; Chabolle, F.

    1988-01-01

    Infections of face and neck represent serious and potentially life threatening conditions that are sometimes difficult to differentiate from neoplasic tumours, especially in subacute clinical forms. Conventional radiographic techniques offer interest for cervical masses, except Ultra-Sonographic examen, in sites regarding vascular axes, but carries little value for evaluating their spread the into different cervical spaces. On the other hand, C.T. is valuable to precise the location and the extent and to determine its inflammatory nature by studying the fats and the aponeurosis around it. It helps in the analysis of associated adjacent signs: soft tissue swelling, extensive obliteration of adjacent fats, swelling of cervical aponeurosis, thickening of adjacent muscles. These findings are documented by the study of fourteen patients, admitted in St-Antopine hospital. All abcesses, except one, were easy to diagnose because of their low central attenuation. False negative cases are possible and noted by other authors. So, in absence of response to appropriate therapy, surgery is necessary to eliminate a misdiagnosed abcess. Furthermore, it's sometimes possible to suspect an etiology (foreign body, tuberculosis) [fr

  3. Adult head CT scans: the uncertainties of effective dose estimates

    International Nuclear Information System (INIS)

    Gregory, Kent J.; Bibbo, Giovanni; Pattison, John E.

    2008-01-01

    Full Text: CT scanning is a high dose imaging modality. Effective dose estimates from CT scans can provide important information to patients and medical professionals. For example, medical practitioners can use the dose to estimate the risk to the patient, and judge whether this risk is outweighed by the benefits of the CT examination, while radiographers can gauge the effect of different scanning protocols on the patient effective dose, and take this into consideration when establishing routine scan settings. Dose estimates also form an important part of epidemiological studies examining the health effects of medical radiation exposures on the wider population. Medical physicists have been devoting significant effort towards estimating patient radiation doses from diagnostic CT scans for some years. The question arises: How accurate are these effective dose estimates? The need for a greater understanding and improvement of the uncertainties in CT dose estimates is now gaining recognition as an important issue (BEIR VII 2006). This study is an attempt to analyse and quantify the uncertainty components relating to effective dose estimates from adult head CT examinations that are calculated with four commonly used methods. The dose estimation methods analysed are the Nagel method, the ImpaCT method, the Wellhoefer method and the Dose-Length Product (DLP) method. The analysis of the uncertainties was performed in accordance with the International Standards Organisation's Guide to the Expression of Uncertainty in Measurement as discussed in Gregory et al (Australas. Phys. Eng. Sci. Med., 28: 131-139, 2005). The uncertainty components vary, depending on the method used to derive the effective dose estimate. Uncertainty components in this study include the statistical and other errors from Monte Carlo simulations, uncertainties in the CT settings and positions of patients in the CT gantry, calibration errors from pencil ionization chambers, the variations in the organ

  4. A Study for Reappearance According to the Scan Type, the CT Scanning by a Moving Phantom

    International Nuclear Information System (INIS)

    Choi, Jae Hyock; Jeong, Do Hyeong; Choi, Gye Suk; Jang, Yo Jong; Kim, Jae Weon; Lee, Hui Seok

    2007-01-01

    CT scan shows that significant tumor movement occurs in lesions located in the proximity of the heart, diaphragm, and lung hilus. There are differences concerning three kinds of type to get images following the Scan type called Axial, Helical, Cine (4D-CT) mode, when the scanning by CT. To know how each protocol describe accurately, this paper is going to give you reappearance using the moving phantom. To reconstruct the movement of superior-inferior and anterior-posterior, the manufactured moving phantom and the motor following breathing were used. To distinguish movement from captured images by CT scanning, a localizer adhered to the marker on the motor. The moving phantom fixed the movement of superior-inferior upon 1.3 cm /1 min. The motor following breathing fixed the movement of anterior-posterior upon 0.2 cm /1 min. After fixing each movement, CT scanning was taken by following the CT protocols. The movement of A localizer and volume-reappearance analyzed by RTP machine. Total volume of a marker was 88.2 cm 3 considering movement of superior-inferior. Total volume was 184.3 cm 3 . Total volume according to each CT scan protocol were 135 cm 3 by axial mode, 164.9 cm 3 by helical mode, 181.7 cm 3 by cine (4D-CT) mode. The most closely describable protocol about moving reappearance was cine mode, the marker attached localizer as well. CT scan should reappear concerning a exact organ-description and target, when the moving organ is being scanned by three kinds of CT protocols. The cine (4D-CT) mode has the advantage of the most highly reconstructible ability of the three protocols in reappearance of the marker using a moving phantom. The marker on the phantom has always regular motion but breathing patients don't move like a phantom. Breathing education and devices setting patients were needed so that images reconstruct breathing as exactly as possible. Users should also consider that an amount of radiation to patients is being bombed.

  5. Synchronized control of spiral CT scan for security inspection device

    International Nuclear Information System (INIS)

    Wang Jue; Jiang Zenghui; Wang Fuquan

    2008-01-01

    In security inspection system of spiral CT, the synchronization between removing and rotating, and the scan synchronization between rotating and sampling influence quality of image reconstruction, so it is difficulty and important that how to realize synchronized scan. According to the controlling demand of multi-slice Spiral CT, the method to realize synchronized scan is given. a synchronized control system is designed, in which we use a industrial PC as the control computer, use magnetic grids as position detectors, use alternating current servo motor and roller motor as drivers respectively drive moving axis and rotating axis. This method can solve the problem of synchronized scan, and has a feasibility and value of use. (authors)

  6. Aquilion ONE / ViSION Edition CT scanner realizing 3D dynamic observation with low-dose scanning

    International Nuclear Information System (INIS)

    Kazama, Masahiro; Saito, Yasuo

    2015-01-01

    Computed tomography (CT) scanners have been continuously advancing as essential diagnostic imaging equipment for the diagnosis and treatment of a variety of diseases, including the three major disease classes of cerebrovascular disease, cardiovascular disease, and cancer. Through the development of helical CT scanners and multislice CT scanners, Toshiba Medical Systems Corporation has developed the Aquilion ONE, a CT scanner with a scanning range of up to 160 mm per rotation that can obtain three-dimensional (3D) images of the brain, heart, and other organs in a single rotation. We have now developed the Aquilion ONE / ViSION Edition, a next-generation 320-row multislice CT scanner incorporating the latest technologies that achieves a shorter scanning time and significant reduction in dose compared with conventional products. This product with its low-dose scanning technology will contribute to the practical realization of new diagnosis and treatment modalities employing four-dimensional (4D) data based on 3D dynamic observations through continuous rotations. (author)

  7. Developing optimized CT scan protocols: Phantom measurements of image quality

    International Nuclear Information System (INIS)

    Zarb, Francis; Rainford, Louise; McEntee, Mark F.

    2011-01-01

    Purpose: The increasing frequency of computerized tomography (CT) examinations is well documented, leading to concern about potential radiation risks for patients. However, the consequences of not performing the CT examination and missing injuries and disease are potentially serious, impacting upon correct patient management. The ALARA principle of dose optimization must be employed for all justified CT examinations. Dose indicators displayed on the CT console as either CT dose index (CTDI) and/or dose length product (DLP), are used to indicate dose and can quantify improvements achieved through optimization. Key scan parameters contributing to dose have been identified in previous literature and in previous work by our group. The aim of this study was to optimize the scan parameters of mA; kV and pitch, whilst maintaining image quality and reducing dose. This research was conducted using psychophysical image quality measurements on a CT quality assurance (QA) phantom establishing the impact of dose optimization on image quality parameters. Method: Current CT scan parameters for head (posterior fossa and cerebrum), abdomen and chest examinations were collected from 57% of CT suites available nationally in Malta (n = 4). Current scan protocols were used to image a Catphan 600 CT QA phantom whereby image quality was assessed. Each scan parameter: mA; kV and pitch were systematically reduced until the contrast resolution (CR), spatial resolution (SR) and noise were significantly lowered. The Catphan 600 images, produced by the range of protocols, were evaluated by 2 expert observers assessing CR, SR and noise. The protocol considered as the optimization threshold was just above the setting that resulted in a significant reduction in CR and noise but not affecting SR at the 95% confidence interval. Results: The limit of optimization threshold was determined for each CT suite. Employing optimized parameters, CTDI and DLP were both significantly reduced (p ≤ 0.001) by

  8. Applicability of three-dimensional imaging techniques in fetal medicine

    Energy Technology Data Exchange (ETDEWEB)

    Werner Junior, Heron; Daltro, Pedro; Gasparetto, Emerson Leandro, E-mail: heronwerner@hotmail.com [Clinica de Diagnostico Por Imagem (CDPI), Rio de Janeiro, RJ (Brazil); Santos, Jorge Lopes dos; Belmonte, Simone; Ribeiro, Gerson [Pontificia Universidade Catolica do Rio de Janeiro (PUC-Rio), RJ (Brazil); Marchiori, Edson [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil)

    2016-09-15

    Objective: To generate physical models of fetuses from images obtained with three-dimensional ultrasound (3D-US), magnetic resonance imaging (MRI), and, occasionally, computed tomography (CT), in order to guide additive manufacturing technology. Materials and Methods: We used 3D-US images of 31 pregnant women, including 5 who were carrying twins. If abnormalities were detected by 3D-US, both MRI and in some cases CT scans were then immediately performed. The images were then exported to a workstation in DICOM format. A single observer performed slice-by-slice manual segmentation using a digital high resolution screen. Virtual 3D models were obtained from software that converts medical images into numerical models. Those models were then generated in physical form through the use of additive manufacturing techniques. Results: Physical models based upon 3D-US, MRI, and CT images were successfully generated. The postnatal appearance of either the aborted fetus or the neonate closely resembled the physical models, particularly in cases of malformations. Conclusion: The combined use of 3D-US, MRI, and CT could help improve our understanding of fetal anatomy. These three screening modalities can be used for educational purposes and as tools to enable parents to visualize their unborn baby. The images can be segmented and then applied, separately or jointly, in order to construct virtual and physical 3D models. (author)

  9. Applicability of three-dimensional imaging techniques in fetal medicine*

    Science.gov (United States)

    Werner Júnior, Heron; dos Santos, Jorge Lopes; Belmonte, Simone; Ribeiro, Gerson; Daltro, Pedro; Gasparetto, Emerson Leandro; Marchiori, Edson

    2016-01-01

    Objective To generate physical models of fetuses from images obtained with three-dimensional ultrasound (3D-US), magnetic resonance imaging (MRI), and, occasionally, computed tomography (CT), in order to guide additive manufacturing technology. Materials and Methods We used 3D-US images of 31 pregnant women, including 5 who were carrying twins. If abnormalities were detected by 3D-US, both MRI and in some cases CT scans were then immediately performed. The images were then exported to a workstation in DICOM format. A single observer performed slice-by-slice manual segmentation using a digital high resolution screen. Virtual 3D models were obtained from software that converts medical images into numerical models. Those models were then generated in physical form through the use of additive manufacturing techniques. Results Physical models based upon 3D-US, MRI, and CT images were successfully generated. The postnatal appearance of either the aborted fetus or the neonate closely resembled the physical models, particularly in cases of malformations. Conclusion The combined use of 3D-US, MRI, and CT could help improve our understanding of fetal anatomy. These three screening modalities can be used for educational purposes and as tools to enable parents to visualize their unborn baby. The images can be segmented and then applied, separately or jointly, in order to construct virtual and physical 3D models. PMID:27818540

  10. Three-dimensional biomedical imaging

    International Nuclear Information System (INIS)

    Robb, R.A.

    1985-01-01

    Scientists in biomedical imaging provide researchers, physicians, and academicians with an understanding of the fundamental theories and practical applications of three-dimensional biomedical imaging methodologies. Succinct descriptions of each imaging modality are supported by numerous diagrams and illustrations which clarify important concepts and demonstrate system performance in a variety of applications. Comparison of the different functional attributes, relative advantages and limitations, complementary capabilities, and future directions of three-dimensional biomedical imaging modalities are given. Volume 1: Introductions to Three-Dimensional Biomedical Imaging Photoelectronic-Digital Imaging for Diagnostic Radiology. X-Ray Computed Tomography - Basic Principles. X-Ray Computed Tomography - Implementation and Applications. X-Ray Computed Tomography: Advanced Systems and Applications in Biomedical Research and Diagnosis. Volume II: Single Photon Emission Computed Tomography. Position Emission Tomography (PET). Computerized Ultrasound Tomography. Fundamentals of NMR Imaging. Display of Multi-Dimensional Biomedical Image Information. Summary and Prognostications

  11. Intrathoracic kidney. Diagnostic value of CT scan imaging

    International Nuclear Information System (INIS)

    Baillet, A.M.; Escure, M.N.

    1988-01-01

    Two cases are reported of an ectopic right kidney that was partially intrathoracic in position. Diagnosis was simple from CT scan imaging appearances, the examination being performed to investigate an intrathoracic mass. Images showed a tissular mass within a fatty zone in sections without contrast and the typical appearance of the kidney on sections with contrast [fr

  12. Serial CT scans and Menkes' kinky hair disease

    International Nuclear Information System (INIS)

    Nakada, Eizo; Kameyama, Junji; Yoshimitsu, Hajime; Mori, Mikio; Tanaka, Mutsuo; Yoshimitsu, Kazunori.

    1988-01-01

    Menkes' kinky hair disease is a sex-linked recessive disorder of copper metabolism, characterized by progressive psychomotor deterioration, seizures, and peculiar hair structure. We examined serial CT scans of patients with this disease. A 2,210-g male infant was delivered after an uneventful gestation of 36 weeks. His one-minute Apgar score was 9. His uncle had died at 1 year of age. His first cousin was also diagnosed as having Menkes' kinky hair disease when our patient was 2 years old. Shortly after birth he had mild respiratory distress. At 5 days of age, he developed setting-sun signs. The first CT scan, at 10 days of age, revealed mild posterior fossa hemorrhages. At 3 months of age, myoclonic seizures began, and the CT scan revealed subdural effusion and mild brain atrophy. The seizures were controllable by using phenobarbital, valproic acid, and nitrazepam. He did not follow light or a fixate, but the fundi were normal. He was diffusely hypotonic. At 9 months of age, the seizures became uncontrollable. The CT scans at 15 and 31 months of age showed subdural hemorrhage and/or brain atrophy. At 15 months of age, the serum copper level was 42 μ g/dl, while the serum ceruloplasmin level was 3.2 mg/dl. He exhibited severe developmental failure. At 4 years of age, he died. (author)

  13. Serial CT scans and Menkes' kinky hair disease

    Energy Technology Data Exchange (ETDEWEB)

    Nakada, Eizo; Kameyama, Junji; Yoshimitsu, Hajime; Mori, Mikio; Tanaka, Mutsuo; Yoshimitsu, Kazunori.

    1988-02-01

    Menkes' kinky hair disease is a sex-linked recessive disorder of copper metabolism, characterized by progressive psychomotor deterioration, seizures, and peculiar hair structure. We examined serial CT scans of patients with this disease. A 2,210-g male infant was delivered after an uneventful gestation of 36 weeks. His one-minute Apgar score was 9. His uncle had died at 1 year of age. His first cousin was also diagnosed as having Menkes' kinky hair disease when our patient was 2 years old. Shortly after birth he had mild respiratory distress. At 5 days of age, he developed setting-sun signs. The first CT scan, at 10 days of age, revealed mild posterior fossa hemorrhages. At 3 months of age, myoclonic seizures began, and the CT scan revealed subdural effusion and mild brain atrophy. The seizures were controllable by using phenobarbital, valproic acid, and nitrazepam. He did not follow light or a fixate, but the fundi were normal. He was diffusely hypotonic. At 9 months of age, the seizures became uncontrollable. The CT scans at 15 and 31 months of age showed subdural hemorrhage and/or brain atrophy. At 15 months of age, the serum copper level was 42 ..mu.. g/dl, while the serum ceruloplasmin level was 3.2 mg/dl. He exhibited severe developmental failure. At 4 years of age, he died.

  14. CT-scanning of ancient Greenlandic Inuit temporal bones

    DEFF Research Database (Denmark)

    Homøe, P; Lynnerup, N; Videbaek, H

    1992-01-01

    Additional morphological evidence of former infectious middle ear disease (IMED) was found by CT-scanning in 5 of 6 Greenlandic Inuit crania strongly suspected for former IMED due to earlier examination revealing either bilateral hypocellularity or asymmetry of the pneumatized area of the temporal...

  15. Technological features and clinical feasibility of megavoltage CT scanning

    International Nuclear Information System (INIS)

    Nakagawa, Keiichi; Aoki, Yukimasa; Akanuma, Atsuo; Sakata, Kouichi; Karasawa, Katsuyuki; Terahara, Atsurou; Onogi, Yuzou; Hasezawa, Kenji; Sasaki, Yasuhito

    1992-01-01

    Megavoltage CT scanning using 4-MV and 6-MV radiotherapy beams has been developed and applied to verify errors in patient positioning. A detector system composed of 120 pairs of cadmium tungstate scintillators with photodiodes is mounted to the treatment unit at a distance of 160 cm from the beam source. Image reconstruction is performed with a standard filtered back-projection algorithm. Scanning time and reconstruction time for a slice is approximately 35 s and 60 s respectively. Although spatial resolution is as large as 4 mm, it has sufficient image quality to be applied for treatment planning and verification. The delivered dose with 4 MV and 6 MV is about 1.4 cGy and 2.8 cGy respectively. When a megavoltage CT image is taken in treatment position, the positioning errors are easily detected by comparing it with diagnostic CT sections for treatment planning. Several clinical examples are presented. (orig.)

  16. CT perfusion scanning of the brain in stroke and beyond

    International Nuclear Information System (INIS)

    Riedel, Christian

    2011-01-01

    CT perfusion scanning (CTP) allows for quantitative analysis of cerebral blood flow (CBF) and cerebral blood volume (CBV). Until recently, it was only possible to study brain perfusion parameters in a small stack of CT-slices close to the skull base. With the introduction of multidetector CT scanners with 64 and more detector rows it has become possible to assess perfusion of the entire brain. An optimal choice of scanning parameters like the new 'shuttle'-technique combined with a well adapted regimen for contrast administration is required to guarantee reliable perfusion measurements while still keeping the X-ray dose absorbed by the patient at a minimum. With these techniques, CTP is not only an important modality in the work-up of patients suffering from acute ischemic stroke but can also be valuable in other emergency situations such as in prolonged epileptic seizures or to monitor patients with subacute subarachnoid hemorrhage. (orig.)

  17. Effect of CT scanning parameters on volumetric measurements of pulmonary nodules by 3D active contour segmentation: a phantom study

    International Nuclear Information System (INIS)

    Way, Ted W; Chan, H-P; Goodsitt, Mitchell M; Sahiner, Berkman; Hadjiiski, Lubomir M; Zhou Chuan; Chughtai, Aamer

    2008-01-01

    The purpose of this study is to investigate the effects of CT scanning and reconstruction parameters on automated segmentation and volumetric measurements of nodules in CT images. Phantom nodules of known sizes were used so that segmentation accuracy could be quantified in comparison to ground-truth volumes. Spherical nodules having 4.8, 9.5 and 16 mm diameters and 50 and 100 mg cc -1 calcium contents were embedded in lung-tissue-simulating foam which was inserted in the thoracic cavity of a chest section phantom. CT scans of the phantom were acquired with a 16-slice scanner at various tube currents, pitches, fields-of-view and slice thicknesses. Scans were also taken using identical techniques either within the same day or five months apart for study of reproducibility. The phantom nodules were segmented with a three-dimensional active contour (3DAC) model that we previously developed for use on patient nodules. The percentage volume errors relative to the ground-truth volumes were estimated under the various imaging conditions. There was no statistically significant difference in volume error for repeated CT scans or scans taken with techniques where only pitch, field of view, or tube current (mA) were changed. However, the slice thickness significantly (p < 0.05) affected the volume error. Therefore, to evaluate nodule growth, consistent imaging conditions and high resolution should be used for acquisition of the serial CT scans, especially for smaller nodules. Understanding the effects of scanning and reconstruction parameters on volume measurements by 3DAC allows better interpretation of data and assessment of growth. Tracking nodule growth with computerized segmentation methods would reduce inter- and intraobserver variabilities

  18. Pulmonary nodule registration in serial CT scans based on rib anatomy and nodule template matching

    International Nuclear Information System (INIS)

    Shi Jiazheng; Sahiner, Berkman; Chan, H.-P.; Hadjiiski, Lubomir; Zhou, C.; Cascade, Philip N.; Bogot, Naama; Kazerooni, Ella A.; Wu, Y.-T.; Wei, J.

    2007-01-01

    An automated method is being developed in order to identify corresponding nodules in serial thoracic CT scans for interval change analysis. The method uses the rib centerlines as the reference for initial nodule registration. A spatially adaptive rib segmentation method first locates the regions where the ribs join the spine, which define the starting locations for rib tracking. Each rib is tracked and locally segmented by expectation-maximization. The ribs are automatically labeled, and the centerlines are estimated using skeletonization. For a given nodule in the source scan, the closest three ribs are identified. A three-dimensional (3D) rigid affine transformation guided by simplex optimization aligns the centerlines of each of the three rib pairs in the source and target CT volumes. Automatically defined control points along the centerlines of the three ribs in the source scan and the registered ribs in the target scan are used to guide an initial registration using a second 3D rigid affine transformation. A search volume of interest (VOI) is then located in the target scan. Nodule candidate locations within the search VOI are identified as regions with high Hessian responses. The initial registration is refined by searching for the maximum cross-correlation between the nodule template from the source scan and the candidate locations. The method was evaluated on 48 CT scans from 20 patients. Experienced radiologists identified 101 pairs of corresponding nodules. Three metrics were used for performance evaluation. The first metric was the Euclidean distance between the nodule centers identified by the radiologist and the computer registration, the second metric was a volume overlap measure between the nodule VOIs identified by the radiologist and the computer registration, and the third metric was the hit rate, which measures the fraction of nodules whose centroid computed by the computer registration in the target scan falls within the VOI identified by the

  19. Three-dimensional biplanar radiography as a new means of accessing femoral version: a comparitive study of EOS three-dimensional radiography versus computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Pomerantz, M.L. [University of California San Diego School of Medicine, Orthopaedic Surgery Department, San Diego, CA (United States); Glaser, Diana [Aurora Spine, Carlsbad, CA (United States); Doan, Josh [Orthopedic Biomechanics Research Center, San Diego, CA (United States); Kumar, Sita [University of California, San Diego, CA (United States); Edmonds, Eric W. [University of California San Diego School of Medicine, Orthopaedic Surgery Department, San Diego, CA (United States); Rady Children' s Hospital San Diego, Division of Orthopedic Surgery, San Diego, CA (United States)

    2014-10-17

    To validate femoral version measurements made from biplanar radiography (BR), three-dimensional (3D) reconstructions (EOS imaging, France) were made in differing rotational positions against the gold standard of computed tomography (CT). Two cadaveric femurs were scanned with CT and BR in five different femoral versions creating ten total phantoms. The native version was modified by rotating through a mid-diaphyseal hinge twice into increasing anteversion and twice into increased retroversion. For each biplanar scan, the phantom itself was rotated -10, -5, 0, +5 and +10 . Three-dimensional CT reconstructions were designated the true value for femoral version. Two independent observers measured the femoral version on CT axial slices and BR 3D reconstructions twice. The mean error (upper bound of the 95 % confidence interval), inter- and intraobserver reliability, and the error compared to the true version were determined for both imaging techniques. Interobserver intraclass correlation for CT axial images ranged from 0.981 to 0.991, and the intraobserver intraclass correlation ranged from 0.994 to 0.996. For the BR 3D reconstructions these values ranged from 0.983 to 0.998 and 0.982 to 0.998, respectively. For the CT measurements the upper bound of error from the true value was 5.4-7.5 , whereas for BR 3D reconstructions it was 4.0-10.1 . There was no statistical difference in the mean error from the true values for any of the measurements done with axial CT or BR 3D reconstructions. BR 3D reconstructions accurately and reliably provide clinical data on femoral version compared to CT even with rotation of the patient of up to 10 from neutral. (orig.)

  20. Comparison of Conventional Versus Spiral Computed Tomography with Three Dimensional Reconstruction in Chronic Otitis Media with Ossicular Chain Destruction

    International Nuclear Information System (INIS)

    Naghibi, Saeed; Seifirad, Sirous; Adami Dehkordi, Mahboobeh; Einolghozati, Sasan; Ghaffarian Eidgahi Moghadam, Nafiseh; Akhavan Rezayat, Amir; Seifirad, Soroush

    2016-01-01

    Chronic otitis media (COM) can be treated with tympanoplasty with or without mastoidectomy. In patients who have undergone middle ear surgery, three-dimensional spiral computed tomography (CT) scan plays an important role in optimizing surgical planning. This study was performed to compare the findings of three-dimensional reconstructed spiral and conventional CT scan of ossicular chain study in patients with COM. Fifty patients enrolled in the study underwent plane and three dimensional CT scan (PHILIPS-MX 8000). Ossicles changes, mastoid cavity, tympanic cavity, and presence of cholesteatoma were evaluated. Results of the two methods were then compared and interpreted by a radiologist, recorded in questionnaires, and analyzed. Logistic regression test and Kappa coefficient of agreement were used for statistical analyses. Sixty two ears with COM were found in physical examination. A significant difference was observed between the findings of the two methods in ossicle erosion (11.3% in conventional CT vs. 37.1% in spiral CT, P = 0.0001), decrease of mastoid air cells (82.3% in conventional CT vs. 93.5% in spiral CT, P = 0.001), and tympanic cavity opacity (12.9% in conventional CT vs. 40.3% in spiral CT, P=0.0001). No significant difference was observed between the findings of the two methods in ossicle destruction (6.5% conventional CT vs. 56.4% in spiral CT, P = 0.125), and presence of cholesteatoma (3.2% in conventional CT vs. 42% in spiral CT, P = 0.172). In this study, spiral CT scan demonstrated ossicle dislocation in 9.6%, decrease of mastoid air cells in 4.8%, and decrease of volume in the tympanic cavity in 1.6%; whereas, none of these findings were reported in the patients' conventional CT scans. Spiral-CT scan is superior to conventional CT in the diagnosis of lesions in COM before operation. It can be used for detailed evaluation of ossicular chain in such patients

  1. Creation of three-dimensional craniofacial standards from CBCT images

    Science.gov (United States)

    Subramanyan, Krishna; Palomo, Martin; Hans, Mark

    2006-03-01

    Low-dose three-dimensional Cone Beam Computed Tomography (CBCT) is becoming increasingly popular in the clinical practice of dental medicine. Two-dimensional Bolton Standards of dentofacial development are routinely used to identify deviations from normal craniofacial anatomy. With the advent of CBCT three dimensional imaging, we propose a set of methods to extend these 2D Bolton Standards to anatomically correct surface based 3D standards to allow analysis of morphometric changes seen in craniofacial complex. To create 3D surface standards, we have implemented series of steps. 1) Converting bi-plane 2D tracings into set of splines 2) Converting the 2D splines curves from bi-plane projection into 3D space curves 3) Creating labeled template of facial and skeletal shapes and 4) Creating 3D average surface Bolton standards. We have used datasets from patients scanned with Hitachi MercuRay CBCT scanner providing high resolution and isotropic CT volume images, digitized Bolton Standards from age 3 to 18 years of lateral and frontal male, female and average tracings and converted them into facial and skeletal 3D space curves. This new 3D standard will help in assessing shape variations due to aging in young population and provide reference to correct facial anomalies in dental medicine.

  2. Three dimensional imaging technique for laser-plasma diagnostics

    International Nuclear Information System (INIS)

    Jiang Shaoen; Zheng Zhijian; Liu Zhongli

    2001-01-01

    A CT technique for laser-plasma diagnostic and a three-dimensional (3D) image reconstruction program (CT3D) have been developed. The 3D images of the laser-plasma are reconstructed by using a multiplication algebraic reconstruction technique (MART) from five pinhole camera images obtained along different sight directions. The technique has been used to measure the three-dimensional distribution of X-ray of laser-plasma experiments in Xingguang II device, and the good results are obtained. This shows that a CT technique can be applied to ICF experiments

  3. Three dimensional imaging technique for laser-plasma diagnostics

    Energy Technology Data Exchange (ETDEWEB)

    Shaoen, Jiang; Zhijian, Zheng; Zhongli, Liu [China Academy of Engineering Physics, Chengdu (China)

    2001-04-01

    A CT technique for laser-plasma diagnostic and a three-dimensional (3D) image reconstruction program (CT3D) have been developed. The 3D images of the laser-plasma are reconstructed by using a multiplication algebraic reconstruction technique (MART) from five pinhole camera images obtained along different sight directions. The technique has been used to measure the three-dimensional distribution of X-ray of laser-plasma experiments in Xingguang II device, and the good results are obtained. This shows that a CT technique can be applied to ICF experiments.

  4. Progress of radiotherapy by three-dimensional treatment planning

    International Nuclear Information System (INIS)

    Imada, Hajime; Nomoto, Satoshi; Takahashi, Hiroyuki; Nakata, Hajime

    1998-01-01

    The recent progress of three-dimensional radiation treatment planning was reviewed. And clinical cases such as lung cancer and breast cancer are introduced. In the University of Occupational and Development Health, the treatment system FOCUS which is made up of CT simulator and linac was used mainly. Three-dimensional treatment planning was carried for about 90% of 330 patients who underwent radiotherapy for one year. The target becomes to be accurate and dose distribution with all CT slices in radiation field can be confirmed by using three-dimensional radiation treatment planning apparatus. High dose irradiation localized to tumor part is possible. Relations between total dose and volume of normal tissue and/or tumor can be estimated numerically and easily by DVH. A prediction of indication and affection became possible by this procedure. In conclusion, generalization of three-dimensional radiation treatment planning will bring progress of more effective radiotherapy with less adverse reaction. (K.H.). 21 refs

  5. CT Scanning in Identification of Sheep Cystic Echinococcosis.

    Science.gov (United States)

    Mao, Rui; Qi, Hongzhi; Pei, Lei; Hao, Jie; Dong, Jian; Jiang, Tao; Ainiwaer, Abudula; Shang, Ge; Xu, Lin; Shou, Xi; Zhang, Songan; Wu, Ge; Lu, Pengfei; Bao, Yongxing; Li, Haitao

    2017-01-01

    We aim to determine the efficiency of CT in identification of cystic echinococcosis in sheep. Fifty-three sheep with liver cysts confirmed by ultrasonography were subject to CT scan to evaluate the number, size, and type of the cysts in liver and lung, confirmed using necropsy. The correlation of numbers between liver cysts and lung cysts was calculated using Pearson analysis. Necropsy indicated a 98% consensus on size, location, number, and activity compared with CT scan. The viable cysts were 53.1% and 50.6% in the liver and lung, respectively. Among the cysts in liver, 35.5%, 9.5%, 5.7%, 10.2%, and 39.1% were Types CE1, CE2, CE3, CE4, and CE5, respectively. The cysts in the lungs, 17.4%, 26.9%, 12.1%, 11.6%, and 32.1%, were Types CE1, CE2, CE3, CE4, and CE5, respectively. A significant correlation was noticed between the number of cysts in liver and those in lung ( R = 0.770, P < 0.001). CT scan is a suitable tool in determining the size and type of cystic hydatid cysts in both liver and lung of sheep. A significant correlation was noticed between the numbers in liver and lung, indicating that lung infection was likely due to the expansion of liver cyst burden pressure.

  6. Helical CT scan for emergent patients with cerebrovascular diseases

    International Nuclear Information System (INIS)

    Matsumoto, Masato; Sato, Naoki; Nakano, Masayuki; Watanabe, Youichi; Kodama, Namio

    1995-01-01

    We studied 44 emergent patients with cerebrovascular diseases (18 cases of subarachnoid hemorrhage, 15 of occlusive lesions, 7 of intracerebral hematoma and 4 of suspected subarachnoid hemorrhage) using helical CT scan. The helical CT scan was performed with contrast medium at a rate of 3 ml/sec with a delay of 20 sec, and was carried out before conventional angiography. The reconstruction time of 3D-CTA was within 10 min. We were able to obtain findings for the lesion on 3D-CTA before those on conventional angiography. The 3D-CTA yielded excellent images of the vascular structures and anatomical relationships of the aneurysm, its neck and parent artery, and surrounding arteries. However, it proved difficult to visualize vessels of less than 1 mm in diameter, especially the perforating arteries. In occlusive diseases, the degree of stenosis depended on the changes in CT number threshold: at present, evaluations of the lesions should be made by conventional angiography. 3D-CTA using helical CT scan can thus be applied for emergent patients with cerebrovascular diseases. Surgical simulation images of 3D-CTA were especially useful at the time of operation. (author)

  7. Helical CT scan for emergent patients with cerebrovascular diseases

    Energy Technology Data Exchange (ETDEWEB)

    Matsumoto, Masato; Sato, Naoki; Nakano, Masayuki; Watanabe, Youichi; Kodama, Namio [Fukushima Medical Coll. (Japan)

    1995-08-01

    We studied 44 emergent patients with cerebrovascular diseases (18 cases of subarachnoid hemorrhage, 15 of occlusive lesions, 7 of intracerebral hematoma and 4 of suspected subarachnoid hemorrhage) using helical CT scan. The helical CT scan was performed with contrast medium at a rate of 3 ml/sec with a delay of 20 sec, and was carried out before conventional angiography. The reconstruction time of 3D-CTA was within 10 min. We were able to obtain findings for the lesion on 3D-CTA before those on conventional angiography. The 3D-CTA yielded excellent images of the vascular structures and anatomical relationships of the aneurysm, its neck and parent artery, and surrounding arteries. However, it proved difficult to visualize vessels of less than 1 mm in diameter, especially the perforating arteries. In occlusive diseases, the degree of stenosis depended on the changes in CT number threshold: at present, evaluations of the lesions should be made by conventional angiography. 3D-CTA using helical CT scan can thus be applied for emergent patients with cerebrovascular diseases. Surgical simulation images of 3D-CTA were especially useful at the time of operation. (author).

  8. Radiation exposure distribution in patients undergoing CT brain scans

    International Nuclear Information System (INIS)

    Yang Zhanshan; Feng Dinghua; Chang Zichi; Li Shijun

    1989-12-01

    The distribution of surface exposures in patients undergoing single and multiple computerized tomographic brain scans with Hitachi CT-W500 was measured by LiF(Mg, Ti) thermoluminescent dosimetry. It was found that there was no significant difference in the sufrace exposures from different scanning slices. However, the exposure doses at different scanning angles around the head were different significantly. The reference point of the maximum surface exposure was at the temporal part of the head. the maximum surface exposure was at 1.65 x 10 -3 C·kg -1 while the average exposure was 1.55 x 10 -3 C·kg -1 . The ratio of the average dose resulting from nine scans to that from a single scan was 1.3, and the surface exposure contribution of scattered radiation was computed. At the same time the radiation doses to eyes, thyroid, chest and gonads of patiens at corresponding position were also measured and were compared with those from CT cranial scans in children and skull radiographic procedures respectively

  9. Utility of three-dimensional method for diagnosing meniscal lesions

    International Nuclear Information System (INIS)

    Ohshima, Suguru; Nomura, Kazutoshi; Hirano, Mako; Hashimoto, Noburo; Fukumoto, Tetsuya; Katahira, Kazuhiro

    1998-01-01

    MRI of the knee is a useful method for diagnosing meniscal tears. Although the spin echo method is usually used for diagnosing meniscal tears, we examined the utility of thin slice scan with the three-dimensional method. We reviewed 70 menisci in which arthroscopic findings were confirmed. In this series, sensitivity was 90.9% for medial meniscal injuries and 68.8% for lateral meniscal injuries. There were 3 meniscal tears in which we could not detect tears on preoperative MRI. We could find tears in two of these cases when re-evaluated using the same MRI. In conclusion, we can get the same diagnostic rate with the three-dimensional method compared with the spin echo method. Scan time of the three-dimensional method is 3 minutes, on the other hand that of spin echo method in 17 minutes. This slice scan with three-dimensional method is useful for screening meniscal injuries before arthroscopy. (author)

  10. Multiparallel Three-Dimensional Optical Microscopy

    Science.gov (United States)

    Nguyen, Lam K.; Price, Jeffrey H.; Kellner, Albert L.; Bravo-Zanoquera, Miguel

    2010-01-01

    Multiparallel three-dimensional optical microscopy is a method of forming an approximate three-dimensional image of a microscope sample as a collection of images from different depths through the sample. The imaging apparatus includes a single microscope plus an assembly of beam splitters and mirrors that divide the output of the microscope into multiple channels. An imaging array of photodetectors in each channel is located at a different distance along the optical path from the microscope, corresponding to a focal plane at a different depth within the sample. The optical path leading to each photodetector array also includes lenses to compensate for the variation of magnification with distance so that the images ultimately formed on all the photodetector arrays are of the same magnification. The use of optical components common to multiple channels in a simple geometry makes it possible to obtain high light-transmission efficiency with an optically and mechanically simple assembly. In addition, because images can be read out simultaneously from all the photodetector arrays, the apparatus can support three-dimensional imaging at a high scanning rate.

  11. Clinical Utility of 4D FDG-PET/CT Scans in Radiation Treatment Planning

    Energy Technology Data Exchange (ETDEWEB)

    Aristophanous, Michalis, E-mail: maristophanous@lroc.harvard.edu [Department of Radiation Oncology, Dana-Farber/Brigham and Women' s Cancer Center and Harvard Medical School, Boston, MA (United States); Berbeco, Ross I.; Killoran, Joseph H. [Department of Radiation Oncology, Dana-Farber/Brigham and Women' s Cancer Center and Harvard Medical School, Boston, MA (United States); Yap, Jeffrey T. [Department of Radiology, Dana-Farber Cancer Institute and Harvard Medical School, Boston, MA (United States); Sher, David J.; Allen, Aaron M.; Larson, Elysia; Chen, Aileen B. [Department of Radiation Oncology, Dana-Farber/Brigham and Women' s Cancer Center and Harvard Medical School, Boston, MA (United States)

    2012-01-01

    Purpose: The potential role of four-dimensional (4D) positron emission tomography (PET)/computed tomography (CT) in radiation treatment planning, relative to standard three-dimensional (3D) PET/CT, was examined. Methods and Materials: Ten patients with non-small-cell lung cancer had sequential 3D and 4D [{sup 18}F]fluorodeoxyglucose PET/CT scans in the treatment position prior to radiation therapy. The gross tumor volume and involved lymph nodes were contoured on the PET scan by use of three different techniques: manual contouring by an experienced radiation oncologist using a predetermined protocol; a technique with a constant threshold of standardized uptake value (SUV) greater than 2.5; and an automatic segmentation technique. For each technique, the tumor volume was defined on the 3D scan (VOL3D) and on the 4D scan (VOL4D) by combining the volume defined on each of the five breathing phases individually. The range of tumor motion and the location of each lesion were also recorded, and their influence on the differences observed between VOL3D and VOL4D was investigated. Results: We identified and analyzed 22 distinct lesions, including 9 primary tumors and 13 mediastinal lymph nodes. Mean VOL4D was larger than mean VOL3D with all three techniques, and the difference was statistically significant (p < 0.01). The range of tumor motion and the location of the tumor affected the magnitude of the difference. For one case, all three tumor definition techniques identified volume of moderate uptake of approximately 1 mL in the hilar region on the 4D scan (SUV maximum, 3.3) but not on the 3D scan (SUV maximum, 2.3). Conclusions: In comparison to 3D PET, 4D PET may better define the full physiologic extent of moving tumors and improve radiation treatment planning for lung tumors. In addition, reduction of blurring from free-breathing images may reveal additional information regarding regional disease.

  12. Construction of realistic phantoms from patient images and a commercial three-dimensional printer.

    Science.gov (United States)

    Leng, Shuai; Chen, Baiyu; Vrieze, Thomas; Kuhlmann, Joel; Yu, Lifeng; Alexander, Amy; Matsumoto, Jane; Morris, Jonathan; McCollough, Cynthia H

    2016-07-01

    The purpose of this study was to use three-dimensional (3-D) printing techniques to construct liver and brain phantoms having realistic pathologies, anatomic structures, and heterogeneous backgrounds. Patient liver and head computed tomography (CT) images were segmented into tissue, vessels, liver lesion, white and gray matter, and cerebrospinal fluid (CSF). Stereolithography files of each object were created and imported into a commercial 3-D printer. Printing materials were assigned to each object after test scans, which showed that the printing materials had CT numbers ranging from 70 to 121 HU at 120 kV. Printed phantoms were scanned on a CT scanner and images were evaluated. CT images of the liver phantom had measured CT numbers of 77.8 and 96.6 HU for the lesion and background, and 137.5 to 428.4 HU for the vessels channels, which were filled with iodine solutions. The difference in CT numbers between lesions and background (18.8 HU) was representative of the low-contrast values needed for optimization tasks. The liver phantom background was evaluated with Haralick features and showed similar texture between patient and phantom images. CT images of the brain phantom had CT numbers of 125, 134, and 108 HU for white matter, gray matter, and CSF, respectively. The CT number differences were similar to those in patient images.

  13. (Weakly) three-dimensional caseology

    International Nuclear Information System (INIS)

    Pomraning, G.C.

    1996-01-01

    The singular eigenfunction technique of Case for solving one-dimensional planar symmetry linear transport problems is extended to a restricted class of three-dimensional problems. This class involves planar geometry, but with forcing terms (either boundary conditions or internal sources) which are weakly dependent upon the transverse spatial variables. Our analysis involves a singular perturbation about the classic planar analysis, and leads to the usual Case discrete and continuum modes, but modulated by weakly dependent three-dimensional spatial functions. These functions satisfy parabolic differential equations, with a different diffusion coefficient for each mode. Representative one-speed time-independent transport problems are solved in terms of these generalised Case eigenfunctions. Our treatment is very heuristic, but may provide an impetus for more rigorous analysis. (author)

  14. Spontaneous spinal epidural hematoma diagnosed by CT scan

    International Nuclear Information System (INIS)

    Abumiya, Takeo; Isu, Toyohiko; Iwasaki, Yoshinobu; Akino, Minoru; Abe, Hiroshi

    1985-01-01

    A case of spinal epidural hematoma diagnosed by CT scan is reported. A 58-year-old man was admitted on June 18, 1984. He had had a sudden onset of severe low-back pain 7 days before admission and had developed paraparesis and numbness of the lower limbs 4 day before admission. Physical examination revealed weakness in the lower limbs, with the reflexes there decreased. The Babinski reflex and the Chaddock reflex were, however, present on both sides. Sensory disturbances were noted below L 2 . Urinary incontinence was present, too. Metrizamide myelography revealed an epidural mass which was located from the power part of T 11 to the upper part of L 2 . A CT scan revealed a biconvex, relatively high-density mass in the posterior spinal canal. On the day of admission, a laminectomy was performed from T 11 to L 1 , and the epidural hematoma was evacuated. The postoperative course was uneventful. Spinal epidural hematoma is uncommon. A CT scan can be used for an early diagnosis of this lesion. According to the review of the CT findings in 15 reported cases, including our case, CT reveals a smoothly marginated biconvex homogeneous density mass. The density of the hematoma decreases with the time. An acute type (within 3 days) is high-density, while a chronic type has a relatively high or isodensity. The acute type is easily differentiated from other epidural masses, such as a herniated disc, an epidural abscess, and an epidural tumor. On the other hand, the diagnosis of the chronic type is not always easy. (author)

  15. Brain atrophy in Huntington's disease: A CT-scan study

    International Nuclear Information System (INIS)

    Starkstein, S.E.; Folstein, S.E.; Brandt, J.; McDonnell, A.; Folstein, M.

    1989-01-01

    CT-scan measurements of cortical and subcortical atrophy were carried out in 34 patients with Huntington's disease (HD). While a significant correlation was observed between parameters of subcortical atrophy (bicaudate ratio, bifrontal ratio and third ventricular ratio) and duration of the disease, there was no significant correlation between these parameters and age. On the other hand, measurements of cortical atrophy (frontal fissure ratio and cortical sulci ratio) correlated significantly with age but not with duration of the disease. When a group of 24 HD patients were compared on CT-scan measurements with a group of 24 age-matched normal controls, significant differences were obtained for all the variables examined, but the bicaudate ratio showed the highest sensitivity and specificity. Even mildly affected patients, with duration of motor symptoms less than 3 years had higher bicaudate ratios than age-matched controls. (orig.)

  16. Progression of CT scan findings in Rett syndrome

    Energy Technology Data Exchange (ETDEWEB)

    Suzuki, Hisaharu; Hirayama, Yoshito; Sakuragawa, Norio; Arima, Masataka (National Center of Neurology and Psychiatry, Kodaira, Tokyo (Japan))

    1989-07-01

    Progression of the lesions revealed by CT scan was observed in five girls with Rett syndrome. The most distinct and common finding was progressive dilatation of Sylvian fissures, frontal extracerebral space, interhemispheric fissure, and sulci mainly in frontal lobe. It may indicate progressive lesion in the frontal and the temporal lobes. In addition, dilatation of the anterior horns of the lateral ventricles and the third ventricle was noted in some cases. Brainstem and cerebellum were small at any age with some morphological development as the patients became elder. Neither malformations nor abnormalities in density were found in any case. It is concluded that the main lesion of Rett syndrome on CT scan is progressive and localized in the frontal and the temporal lobes. (author).

  17. Equilibrium: three-dimensional configurations

    International Nuclear Information System (INIS)

    Anon.

    1987-01-01

    This chapter considers toroidal MHD configurations that are inherently three-dimensional. The motivation for investigation such complicated equilibria is that they possess the potential for providing toroidal confinement without the need of a net toroidal current. This leads to a number of advantages with respect to fusion power generation. First, the attractive feature of steady-state operation becomes more feasible since such configurations no longer require a toroidal current transformer. Second, with zero net current, one potentially dangerous class of MHD instabilities, the current-driven kink modes, is eliminated. Finally, three-dimensional configurations possess nondegenerate flux surfaces even in the absence of plasma pressure and plasma current. Although there is an enormous range of possible three-dimensional equilibria, the configurations of interest are accurately described as axisymmetric tori with superimposed helical fields; furthermore, they possess no net toroidal current. Instead, two different and less obvious restoring forces are developed: the helical sideband force and the toroidal dipole current force. Each is discussed in detail in Chapter 7. A detailed discussion of the parallel current constraint, including its physical significance, is given in section 7.2. A general analysis of helical sideband equilibria, along with a detailed description of the Elmo bumpy torus, is presented in sections 7.3 and 7.4. A general description of toroidal dipole-current equilibria, including a detailed discussion of stellarators, heliotrons, and torsatrons, is given in sections 7.5 and 7.6

  18. Topographic diagnosis of parathyroid tumor by CT scan

    International Nuclear Information System (INIS)

    Fukunaga, Masao; Harioka, Toshio; Morita, Rikuji

    1981-01-01

    In order to detect the hyperfunctioning parathyroid gland(s), CT scan over the neck was performed in patients with parathyroid disorders, including 10 primary hyperparathyroidism (6 bone type, 3 stone type and 1 chemical type), 8 chronic renal failure on hemodialysis with renal osteodystrophy and 2 multiple endocrine adenomatosis (MEA) type I. We used a whole-body scanner (CT/T, GE). The slice thickness was 5 mm. All patients were scanned from the sternal notch upward to the larynx, and were enhanced by the administration of 30% DIP Conray for 15 min. The results of the topographic diagnosis were compared with the surgical findings. Precise preoperative localization was accomplished in 9/10 adenomas in primary hyperparathyroidism, 27/32 hyperplasias in secondary hyperparathyroidism, and 2/4 hyperplasias in MEA type I. The smallest lesion weighed 0.2 g. It was shown that CT scan over the neck was a noninvasive and simple method to define the localization of hyperfunctionig parathyroid gland(s). (author)

  19. Dose profile study in head CT scans using radiochromic films

    Energy Technology Data Exchange (ETDEWEB)

    Ladino G, A. M.; Prata M, A., E-mail: amlgphys@gmail.com [Universidade Federal de Minas Gerais, Departamento de Engenharia Nuclear, Av. Pte. Antonio Carlos 6627, 31270-901 Belo Horizonte, Minas Gerais (Brazil)

    2016-10-15

    Diagnostic images of computed tomography generate higher doses than other methods of diagnostic radiology using X-ray beam attenuation. Clinical applications of CT have been increased by technological advances, what leads to a wide variety of scanner in the Brazilian technological pool. It has been difficult to implement dose reduction strategies because of the lack of proper guidance on computed tomography examinations. However, CT scanners allow adjusting acquisition parameter according to the patients physical profile and diagnostic application for which the scan is intended. The knowledge of the dose distribution is important because changes in image acquisition parameters may provide dose reduction. In this study, it was used a cylindrical head phantom in PMMA with 5 openings, what allows dose measurement in 5 regions. In a GE CT scanner, Discovery model of 64 channels, the central slice of the head phantom was irradiated and the absorbed doses were measured using a pencil ionization chamber. Radiochromic film strips were placed in the peripheral and in the central region of the head phantom and was performed a scan of 10 cm in the phantom central region. The scan was performed using the head scanning protocol of the radiobiology service, with a voltage of 120 kV. After scanning, the radiochromic film strips were digitalized and their digital images were used to have the dose longitudinal profiles. The dose values recorded have variation in a range of 18.66 to 23.57 mGy. In the results it was compared the dose index values obtained by the pencil chamber measurement to the dose longitudinal profiles recorded by the film strips. (Author)

  20. Dose profile study in head CT scans using radiochromic films

    International Nuclear Information System (INIS)

    Ladino G, A. M.; Prata M, A.

    2016-10-01

    Diagnostic images of computed tomography generate higher doses than other methods of diagnostic radiology using X-ray beam attenuation. Clinical applications of CT have been increased by technological advances, what leads to a wide variety of scanner in the Brazilian technological pool. It has been difficult to implement dose reduction strategies because of the lack of proper guidance on computed tomography examinations. However, CT scanners allow adjusting acquisition parameter according to the patients physical profile and diagnostic application for which the scan is intended. The knowledge of the dose distribution is important because changes in image acquisition parameters may provide dose reduction. In this study, it was used a cylindrical head phantom in PMMA with 5 openings, what allows dose measurement in 5 regions. In a GE CT scanner, Discovery model of 64 channels, the central slice of the head phantom was irradiated and the absorbed doses were measured using a pencil ionization chamber. Radiochromic film strips were placed in the peripheral and in the central region of the head phantom and was performed a scan of 10 cm in the phantom central region. The scan was performed using the head scanning protocol of the radiobiology service, with a voltage of 120 kV. After scanning, the radiochromic film strips were digitalized and their digital images were used to have the dose longitudinal profiles. The dose values recorded have variation in a range of 18.66 to 23.57 mGy. In the results it was compared the dose index values obtained by the pencil chamber measurement to the dose longitudinal profiles recorded by the film strips. (Author)

  1. Polycrystal model of the mechanical behavior of a Mo–TiC30vol.% metal–ceramic composite using a three-dimensional microstructure map obtained by dual beam focused ion beam scanning electron microscopy

    International Nuclear Information System (INIS)

    Cédat, D.; Fandeur, O.; Rey, C.; Raabe, D.

    2012-01-01

    The mechanical behavior of a Mo–TiC 30vol.% ceramic–metal composite was investigated over a wide temperature range (25–700 °C). High-energy X-ray tomography was used to reveal percolation of the hard titanium carbide phase through the composite. Using a polycrystal approach for a two-phase material, finite-element simulations were performed on a real three-dimensional (3-D) aggregate of the material. The 3-D microstructure, used as the starting configuration for the predictions, was obtained by serial sectioning in a dual beam focused ion beam scanning electron microscope coupled to an electron backscattered diffraction system. The 3-D aggregate consists of a molybdenum matrix and a percolating TiC skeleton. As for most body-centered cubic (bcc) metals, the molybdenum matrix phase is characterized by a change in plasticity mechanism with temperature. We used a polycrystal model for bcc materials which was extended to two phases (TiC and Mo). The model parameters of the matrix were determined from experiments on pure molydenum. For all temperatures investigated the TiC particles were considered to be brittle. Gradual damage to the TiC particles was treated, based on an accumulative failure law that is approximated by evolution of the apparent particle elastic stiffness. The model enabled us to determine the evolution of the local mechanical fields with deformation and temperature. We showed that a 3-D aggregate representing the actual microstructure of the composite is required to understand the local and global mechanical properties of the composite studied.

  2. Pathophysiological study of experimental hydrocephalus with computed tomography (CT) scan

    International Nuclear Information System (INIS)

    Murata, Takaho

    1980-01-01

    In order to investigate the pathophysiological changes during a development of hydrocephalus, the observations employing computed tomography (CT) scans and monitorings of intracranial epidural pressure (EDP) were performed in a series of kaolin-induced canine hydrocephalus. According to ''volume index'' of ventricles which was calculated from printed-out