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Sample records for computed tomographic analysis

  1. Radiographic test phantom for computed tomographic lung nodule analysis

    International Nuclear Information System (INIS)

    Zerhouni, E.A.

    1987-01-01

    This patent describes a method for evaluating a computed tomograph scan of a nodule in a lung of a human or non-human animal. The method comprises generating a computer tomograph of a transverse section of the animal containing lung and nodule tissue, and generating a second computer tomograph of a test phantom comprising a device which simulates the transverse section of the animal. The tissue simulating portions of the device are constructed of materials having radiographic densities substantially identical to those of the corresponding tissue in the simulated transverse section of the animal and have voids therein which simulate, in size and shape, the lung cavities in the transverse section and which contain a test reference nodule constructed of a material of predetermined radiographic density which simulates in size, shape and position within a lung cavity void of the test phantom the nodule in the transverse section of the animal and comparing the respective tomographs

  2. Computer tomographs

    International Nuclear Information System (INIS)

    Niedzwiedzki, M.

    1982-01-01

    Physical foundations and the developments in the transmission and emission computer tomography are presented. On the basis of the available literature and private communications a comparison is made of the various transmission tomographs. A new technique of computer emission tomography ECT, unknown in Poland, is described. The evaluation of two methods of ECT, namely those of positron and single photon emission tomography is made. (author)

  3. Computer tomographic diagnosis of echinococcosis

    Energy Technology Data Exchange (ETDEWEB)

    Haertel, M.; Fretz, C.; Fuchs, W.A.

    1980-08-01

    The computer tomographic appearances and differential diagnosis in 22 patients with echinococcosis are described; of these, twelve were of the cystic and ten of the alveolar type. The computer tomographic appearances are characterised by the presence of daughter cysts (66%) within the sharply demarkated parasitic cyst of water density. In the absence of daughter cysts, a definite aetiological diagnosis cannot be made, although there is a tendency to clasification of the occassionally multiple echinococcus cysts. The computer tomographic appearances of advanced alveolar echinococcosis are characterised by partial collequative necrosis, with clacification around the necrotic areas (90%). The absence of CT evidence of partial necrosis and calsification of the pseudotumour makes it difficult to establish a specific diagnosis. The conclusive and non-invasive character of the procedure and its reproducibility makes computer tomography the method of choice for the diagnosis and follow-up of echinococcosis.

  4. Comparative study of the macroscopic finding, conventional tomographic imaging, and computed tomographic imaging in locating the mandibular canal

    International Nuclear Information System (INIS)

    Choi, Hang Moon; You, Dong Soo

    1995-01-01

    The purpose of this study was comparison of conventional tomography with reformatted computed tomography for dental implant in locating the mandibular canal. Five dogs were used and after conventional tomographs and fitted computed tomographs were taken, four dentist traced all films. Mandibles were sectioned with 2 mm slice thickness and the sections were then radiographed (contact radiography). Each radiograpic image was traced and linear measurements were made from mandibular canal to alveolar crest, buccal cortex, lingual cortex, and inferior border. The following results were obtained; 1. Reformatted computed tomographs were exacter than conventional tomography by alveolar crest to canal length of -0.6 mm difference between real values and radiographs 2. The average measurements of buccal cortex to mandibular canal width and lingual cortex to mandibular canal width of conventional tomographs were exacter than reformatted computed tomographs, but standard deviations were higher than reformatted computed tomographs. 3. Standard deviations of reformatted computed tomographs were lower than conventional tomographs at all comparing sites 4. At reformatted computed tomography 62.5% of the measurements performed were within ±1 mm of the true value, and at conventional tomography 24.1% were. 5. Mandibular canal invisibility was 0.8% at reformatted computed tomography and 9.2% at conventional tomography. Reformatted computed tomography has been shown to be more useful radiographic technique for assessment of the mandibular canal than conventional tomography.

  5. Computed tomographic appearances of sternocostoclavicular hyperostosis

    Energy Technology Data Exchange (ETDEWEB)

    Chigira, Masaki; Shimizu, Toru (Gunma Univ. (Japan). Dept. of Orthopaedic Surgery)

    1989-08-01

    Computed tomographical analysis of sternocostoclavicular hyperostosis was performed in 27 patients. In the earliest stage hyperostosis occurred around the cartilaginous portion of the first ribs. The sternoclavicular joint space was preserved even in the late stage III of the disorder. It is also suggested that perichondritis and periostitis play important roles in the etiology of this disorder. (orig./GDG).

  6. Computed tomographic appearances of sternocostoclavicular hyperostosis

    International Nuclear Information System (INIS)

    Chigira, Masaki; Shimizu, Toru

    1989-01-01

    Computed tomographical analysis of sternocostoclavicular hyperostosis was performed in 27 patients. In the earliest stage hyperostosis occurred around the cartilaginous portion of the first ribs. The sternoclavicular joint space was preserved even in the late stage III of the disorder. It is also suggested that perichondritis and periostitis play important roles in the etiology of this disorder. (orig./GDG)

  7. Computed tomographic findings of intracranial pyogenic abscess

    International Nuclear Information System (INIS)

    Kim, S. J.; Suh, J. H.; Park, C. Y.; Lee, K. C.; Chung, S. S.

    1982-01-01

    The early diagnosis and effective treatment of brain abscess pose a difficult clinical problem. With the advent of computed tomography, however, it appears that mortality due to intracranial abscess has significantly diminished. 54 cases of intracranial pyogenic abscess are presented. Etiologic factors and computed tomographic findings are analyzed and following result are obtained. 1. The common etiologic factors are otitis media, post operation, and head trauma, in order of frequency. 2. The most common initial computed tomographic findings of brain abscess is ring contrast enhancement with surrounding brain edema. 3. The most characteristic computed tomographic finding of ring contrast enhancement is smooth thin walled ring contrast enhancement. 4. Most of thick irregular ring contrast enhancement are abscess associated with cyanotic heart disease or poor operation. 5. The most common findings of epidural and subdural empyema is crescentic radiolucent area with thin wall contrast enhancement without surrounding brain edema in convexity of brain

  8. Computed Tomographic Analysis of Ventral Atlantoaxial Optimal Safe Implantation Corridors in 27 Dogs.

    Science.gov (United States)

    Leblond, Guillaume; Gaitero, Luis; Moens, Noel M M; Zur Linden, Alex; James, Fiona M K; Monteith, Gabrielle J; Runciman, John

    2017-11-01

    Objectives  Ventral atlantoaxial stabilization techniques are challenging surgical procedures in dogs. Available surgical guidelines are based upon subjective anatomical landmarks, and limited radiographic and computed tomographic data. The aims of this study were (1) to provide detailed anatomical descriptions of atlantoaxial optimal safe implantation corridors to generate objective recommendations for optimal implant placements and (2) to compare anatomical data obtained in non-affected Toy breed dogs, affected Toy breed dogs suffering from atlantoaxial instability and non-affected Beagle dogs. Methods  Anatomical data were collected from a prospectively recruited population of 27 dogs using a previously validated method of optimal safe implantation corridor analysis using computed tomographic images. Results  Optimal implant positions and three-dimensional numerical data were generated successfully in all cases. Anatomical landmarks could be used to generate objective definitions of optimal insertion points which were applicable across all three groups. Overall the geometrical distribution of all implant sites was similar in all three groups with a few exceptions. Clinical Significance  This study provides extensive anatomical data available to facilitate surgical planning of implant placement for atlantoaxial stabilization. Our data suggest that non-affected Toy breed dogs and non-affected Beagle dogs constitute reasonable research models to study atlantoaxial stabilization constructs. Schattauer GmbH Stuttgart.

  9. Experience of computed tomographic myelography and discography in cervical problem

    Energy Technology Data Exchange (ETDEWEB)

    Nakatani, Shigeru; Yamamoto, Masayuki; Uratsuji, Masaaki; Suzuki, Kunio; Matsui, Eigo [Hyogo Prefectural Awaji Hospital, Sumoto, Hyogo (Japan); Kurihara, Akira

    1983-06-01

    CTM (computed tomographic myelography) was performed on 15 cases of cervical lesions, and on 5 of them, CTD (computed tomographic discography) was also made. CTM revealed the intervertebral state, and in combination with CTD, providing more accurate information. The combined method of CTM and CTD was useful for soft disc herniation.

  10. Computed tomographic findings of intracranial gliosis

    International Nuclear Information System (INIS)

    Weisberg, L.

    1981-01-01

    The clinical and computed tomographic (CT) findings in eight patients with pathological evidence of cerebral gliosis are analyzed. CT findings do not permit differentiation of gliosis from other neoplastic and non-neoplastic conditions. (orig.)

  11. A Novel Quantitative Computed Tomographic Analysis Suggests How Sirolimus Stabilizes Progressive Air Trapping in Lymphangioleiomyomatosis.

    Science.gov (United States)

    Argula, Rahul G; Kokosi, Maria; Lo, Pechin; Kim, Hyun J; Ravenel, James G; Meyer, Cristopher; Goldin, Jonathan; Lee, Hye-Seung; Strange, Charlie; McCormack, Francis X

    2016-03-01

    The Multicenter International Lymphangioleiomyomatosis Efficacy and Safety of Sirolimus (MILES) trial demonstrated that sirolimus stabilized lung function and improved measures of functional performance and quality of life in patients with lymphangioleiomyomatosis. The physiologic mechanisms of these beneficial actions of sirolimus are incompletely understood. To prospectively determine the longitudinal computed tomographic lung imaging correlates of lung function change in MILES patients treated with placebo or sirolimus. We determined the baseline to 12-month change in computed tomographic image-derived lung volumes and the volume of the lung occupied by cysts in the 31 MILES participants (17 in sirolimus group, 14 in placebo group) with baseline and 12-month scans. There was a trend toward an increase in median expiratory cyst volume percentage in the placebo group and a reduction in the sirolimus group (+2.68% vs. +0.97%, respectively; P = 0.10). The computed tomographic image-derived residual volume and the ratio of residual volume to total lung capacity increased more in the placebo group than in the sirolimus group (+214.4 ml vs. +2.9 ml [P = 0.054] and +0.05 ml vs. -0.01 ml [P = 0.0498], respectively). A Markov transition chain analysis of respiratory cycle cyst volume changes revealed greater dynamic variation in the sirolimus group than in the placebo group at the 12-month time point. Collectively, these data suggest that sirolimus attenuates progressive gas trapping in lymphangioleiomyomatosis, consistent with a beneficial effect of the drug on airflow obstruction. We speculate that a reduction in lymphangioleiomyomatosis cell burden around small airways and cyst walls alleviates progressive airflow limitation and facilitates cyst emptying.

  12. Diagnostic accuracy of multi-slice computed tomographic angiography in the detection of cerebral aneurysms

    International Nuclear Information System (INIS)

    Haghighatkhah, H. R.; Sabouri, S.; Borzouyeh, F.; Bagherzadeh, M. H.; Bakhshandeh, H.; Jalali, A. H.

    2008-01-01

    Multislice computed tomographic angiography is a rapid and minimally invasive method for the detection of intracranial aneurysms. The purpose of this study was to compare Multislice computed tomographic angiography with digital subtraction angiography In the diagnosis of cerebral aneurysms. Patients and Methods: In this cross sectional study we evaluated 111 consecutive patients [42(37.8%) male and 69(62.2%) female], who were admitted under clinical symptoms and signs. suggestive of harboring an intracranial aneurysm by using a four detector Multislice computed tomographic angiography. Then we compared results of Multislice computed tomographic angiography with digital subtraction angiography results as a gold standard method. Digital subtraction angiography was performed by bilateral selective common carotid artery injections and either unilateral or bilateral vertebral artery injections, as necessary. Multislice computed tomographic angiography images were interpreted by one radiologist and digital subtraction angiography was performed by another radiologist who was blinded to the interpretation of the Multislice computed tomographic angiograms. Results: The mean ±S D age of the patients was 49.1±13.6 years (range: 12-84 years). We performed Multislice computed tomographic in 111 and digital subtraction angiography in 85 patients. The sensitivity, specificity, positive predictive value, negative predictive value, positive and negative likelihood ratio of Multislice computed tomographic angiography, when compared with digital subtraction angiography as the gold standard, were 100%, 90%, 87.5%, 100%, 10 and 0, respectively. Conclusion: Multislice computed tomographic angiography seems to be an accurate and noninvasive imaging modality in the diagnosis of intracranial aneurysms

  13. Computed tomographic findings of traumatic intracranial lesions

    International Nuclear Information System (INIS)

    Jeong, Seong Wook; Kim, Il Young; Lee, Byung Ho; Kim, Ki Jeoung; Yoon, Il Gyu

    1985-01-01

    Traumatic intracranial lesion has been one of the most frequent and serious problem in neurosurgical pathology. Computed tomography made it possible to get prompt diagnosis and surgical intervention of intracranial lesions by its safety, fastness and accuracy. Computed tomographic scan was carried out on 1309 cases at Soonchunhyang Chunan Hospital for 15 months from October 1983 to December 1984. We have reviewed the computed tomographic scans of 264 patients which showed traumatic intracranial lesion. The result were as follows: 1. Head trauma was the most frequent diagnosed disease using computed tomographic scans (57.8%) and among 264 cases the most frequent mode of injury was traffic accident (73.9%). 2. Skull fracture was accompanied in frequency of 69.7% and it was detected in CT in 38.6%: depression fracture was more easily detected in 81%. 3. Conutercoup lesion (9.5%) was usually accompanied with temporal and occipital fracture, and it appeared in lower incidence among pediatric group. 4. Intracranial lesions of all 264 cases were generalized cerebral swelling (24.6%), subdural hematoma (22.3%), epidural hematoma (20.8%), intracerebral hematoma (6.1%), and subarachnoid hemorrhage (3.0%). 5. The shape of hematoma was usually biconvex (92.7%) in acute epidural hematoma and cresentic (100%) in acute subdural hematoma, but the most chronic the case became, they showed planoconvex and bicconvex shapes. 6. Extra-axial hematoma was getting decreased in density as time gone by. 7. Hematoma density was not in direct proportion to serum hemoglobin level as single factor

  14. Computed tomographic findings of traumatic intracranial lesions

    Energy Technology Data Exchange (ETDEWEB)

    Jeong, Seong Wook; Kim, Il Young; Lee, Byung Ho; Kim, Ki Jeoung; Yoon, Il Gyu [Soonchunhyang University College of Medicine, Seoul (Korea, Republic of)

    1985-10-15

    Traumatic intracranial lesion has been one of the most frequent and serious problem in neurosurgical pathology. Computed tomography made it possible to get prompt diagnosis and surgical intervention of intracranial lesions by its safety, fastness and accuracy. Computed tomographic scan was carried out on 1309 cases at Soonchunhyang Chunan Hospital for 15 months from October 1983 to December 1984. We have reviewed the computed tomographic scans of 264 patients which showed traumatic intracranial lesion. The result were as follows: 1. Head trauma was the most frequent diagnosed disease using computed tomographic scans (57.8%) and among 264 cases the most frequent mode of injury was traffic accident (73.9%). 2. Skull fracture was accompanied in frequency of 69.7% and it was detected in CT in 38.6%: depression fracture was more easily detected in 81%. 3. Conutercoup lesion (9.5%) was usually accompanied with temporal and occipital fracture, and it appeared in lower incidence among pediatric group. 4. Intracranial lesions of all 264 cases were generalized cerebral swelling (24.6%), subdural hematoma (22.3%), epidural hematoma (20.8%), intracerebral hematoma (6.1%), and subarachnoid hemorrhage (3.0%). 5. The shape of hematoma was usually biconvex (92.7%) in acute epidural hematoma and cresentic (100%) in acute subdural hematoma, but the most chronic the case became, they showed planoconvex and bicconvex shapes. 6. Extra-axial hematoma was getting decreased in density as time gone by. 7. Hematoma density was not in direct proportion to serum hemoglobin level as single factor.

  15. Computed Tomographic Perfusion Improves Diagnostic Power of Coronary Computed Tomographic Angiography in Women

    DEFF Research Database (Denmark)

    Penagaluri, Ashritha; Higgins, Angela Y.; Vavere, Andrea L

    2016-01-01

    laboratories. Prevalence of flow-limiting CAD defined by invasive coronary angiography equal to 50% or greater with an associated single-photon emission computed tomography myocardial perfusion imaging defect was 45% (114/252) and 23% (30/129) in males and females, respectively. Patient-based diagnostic......Background-Coronary computed tomographic angiography (CTA) and myocardial perfusion imaging (CTP) is a validated approach for detection and exclusion of flow-limiting coronary artery disease (CAD), but little data are available on gender-specific performance of these modalities. In this study, we...... aimed to evaluate the diagnostic accuracy of combined coronary CTA and CTP in detecting flow-limiting CAD in women compared with men.  Methods and Results-Three hundred and eighty-one patients who underwent both CTA-CTP and single-photon emission computed tomography myocardial perfusion imaging...

  16. Computed-tomographic determination of mineral content of bones

    International Nuclear Information System (INIS)

    Delov, I.; Tabakov, S.

    1988-01-01

    The problem of precise computed-tomographic densitometry of the mineral content of bones is pointed out. A method is proposed including the use of standard density and observance of definite radiation, scanning and image estimation parameters. A good correlation of the results obtained for the mineral content of the lumbar vertebrae with literature data are reported. A method is also described for determining the mineral content of tubular bones based on densiprofile check-up of the computed-tomographic density. The procedure takes 10-15 minutes and includes 1 or 2 scans. It might therefore gain wide acceptance for the diagnosis and tracing of osteoporosis and other osteopathies associated with distrorted calcium metabolism

  17. Emission computed tomograph

    International Nuclear Information System (INIS)

    Hirose, Y.; Kanno, I.; Koga, K.; Miura, S.; Uemura, K.

    1981-01-01

    Emission computed tomograph wherein a pluralty of detectors surround an object to be examined so as to detect x- or gamma radiation emitted by said object. In front of each of said detectors there is provided a collimator which comprises a pair of main plates and a subsidiary plate interposed therebetween. The plates are made of a material capable of blocking penetration of the radiation therethrough and so supported as to be swingable over an angle sufficient to cover the whole of said object. The plates of all the collimators are simultaneously swung to the same side and at the same angular speed thereby to change the direction of incidence of said radiation on each of said detectors

  18. Computed tomographic analysis of temporal maxillary stability and pterygomaxillary generate formation following pediatric Le Fort III distraction advancement.

    Science.gov (United States)

    Hopper, Richard A; Sandercoe, Gavin; Woo, Albert; Watts, Robyn; Kelley, Patrick; Ettinger, Russell E; Saltzman, Babette

    2010-11-01

    Le Fort III distraction requires generation of bone in the pterygomaxillary region. The authors performed retrospective digital analysis on temporal fine-cut computed tomographic images to quantify both radiographic evidence of pterygomaxillary region bone formation and relative maxillary stability. Fifteen patients with syndromic midface hypoplasia were included in the study. The average age of the patients was 8.7 years; 11 had either Crouzon or Apert syndrome. The average displacement of the maxilla during distraction was 16.2 mm (range, 7 to 31 mm). Digital analysis was performed on fine-cut computed tomographic scans before surgery, at device removal, and at annual follow-up. Seven patients also had mid-consolidation computed tomographic scans. Relative maxillary stability and density of radiographic bone in the pterygomaxillary region were calculated between each scan. There was no evidence of clinically significant maxillary relapse, rotation, or growth between the end of consolidation and 1-year follow-up, other than a relatively small 2-mm subnasal maxillary vertical growth. There was an average radiographic ossification of 0.5 mm/mm advancement at the time of device removal, with a 25th percentile value of 0.3 mm/mm. The time during consolidation that each patient reached the 25th percentile of pterygomaxillary region bone density observed in this series of clinically stable advancements ranged from 1.3 to 9.8 weeks (average, 3.7 weeks). There was high variability in the amount of bone formed in the pterygomaxillary region associated with clinical stability of the advanced Le Fort III segment. These data suggest that a subsection of patients generate the minimal amount of pterygomaxillary region bone formation associated with advancement stability as early as 4 weeks into consolidation.

  19. Computed tomographic appearances of cherubism

    Energy Technology Data Exchange (ETDEWEB)

    Bianchi, S D; Boccardi, A; Mela, F; Romagnoli, R

    1987-01-01

    The computed tomographic (CT) aspects of six cases of cherubism are described. Through its optimal representation of the lesions, CT enabled certain characteristics of this disease to be substantiated, namely, limitation of the process to the bones of the jaw and primarily superficial development of the mandibular lesions, coupled with an unusual mandibular condylar impairment. Moreover, the composition of this series permitted investigation of the condition in its several stages of progression.

  20. Reciprocating vs Rotary Instrumentation in Pediatric Endodontics: Cone Beam Computed Tomographic Analysis of Deciduous Root Canals using Two Single-file Systems.

    Science.gov (United States)

    Prabhakar, Attiguppe R; Yavagal, Chandrashekar; Dixit, Kratika; Naik, Saraswathi V

    2016-01-01

    Primary root canals are considered to be most challenging due to their complex anatomy. "Wave one" and "one shape" are single-file systems with reciprocating and rotary motion respectively. The aim of this study was to evaluate and compare dentin thickness, centering ability, canal transportation, and instrumentation time of wave one and one shape files in primary root canals using a cone beam computed tomographic (CBCT) analysis. This is an experimental, in vitro study comparing the two groups. A total of 24 extracted human primary teeth with minimum 7 mm root length were included in the study. Cone beam computed tomographic images were taken before and after the instrumentation for each group. Dentin thickness, centering ability, canal transportation, and instrumentation times were evaluated for each group. A significant difference was found in instrumentation time and canal transportation measures between the two groups. Wave one showed less canal transportation as compared with one shape, and the mean instrumentation time of wave one was significantly less than one shape. Reciprocating single-file systems was found to be faster with much less procedural errors and can hence be recommended for shaping the root canals of primary teeth. How to cite this article: Prabhakar AR, Yavagal C, Dixit K, Naik SV. Reciprocating vs Rotary Instrumentation in Pediatric Endodontics: Cone Beam Computed Tomographic Analysis of Deciduous Root Canals using Two Single-File Systems. Int J Clin Pediatr Dent 2016;9(1):45-49.

  1. Case Report: Unusual computed tomographic features of ...

    African Journals Online (AJOL)

    A case report of a 57-year old woman who presented with signs and symptoms of intracranial mass. Computed tomographic (CT) and clinical features were unusual and suggestive of a parasaggital Meningioma. However an accurate diagnosis of a tuberculoma was made at surgery and histopathological examination.

  2. Design and applications of Computed Industrial Tomographic Imaging System (CITIS)

    International Nuclear Information System (INIS)

    Ramakrishna, G.S.; Umesh Kumar; Datta, S.S.; Rao, S.M.

    1996-01-01

    Computed tomographic imaging is an advanced technique for nondestructive testing (NDT) and examination. For the first time in India a computed aided tomography system has been indigenously developed in BARC for testing industrial components and was successfully demonstrated. The system in addition to Computed Tomography (CT) can also perform Digital Radiography (DR) to serve as a powerful tool for NDT applications. It has wider applications in the fields of nuclear, space and allied fields. The authors have developed a computed industrial tomographic imaging system with Cesium 137 gamma radiation source for nondestructive examination of engineering and industrial specimens. This presentation highlights the design and development of a prototype system and its software for image reconstruction, simulation and display. The paper also describes results obtained with several tests specimens, current development and possibility of using neutrons as well as high energy x-rays in computed tomography. (author)

  3. Computed tomographic evaluation of the altered pancreas in dog and cat

    International Nuclear Information System (INIS)

    Posch, B.

    2002-11-01

    Eighteen dogs and 12 cats of varying breed, age and sex underwent a computed tomographic study of the pancreas. Length, diameter and density of each lobe of the pancreas were measured. Further, the gained results were compared to the information established by the clinical examination, sonography, haematology and histology. Contrast CT improved evaluation of the pancreas in all cases of normal life controls. CT criteria such as changes in size, density, delimitation of the pancreas and the peripancreatic structures were analyzed. Increased pancreatic size was seen in inflammatory as well as in neoplastic diseases. There were no reliable computed tomographic criteria to differentiate pancreatic neoplasia from inflammation without peripancreatic findings. Ultrasonography proved to be a good screening method in this study: sonographic and computed tomographic results correlated in all cases with the exception of 5 cases. In contrast to ultrasonography CT could differentiate normal pancreas from pancreas atrophy. Computed tomography was superior to sonography in determining the full extent of pancreatic and peripancreatic signs due to the good overview and overall image of the abdominal structures. Serum chemistry of a- amylase and lipase were obtained in 28 animals. Assays of serum lipase and a- amylase activities were only able to detect acute pancreatitis in half of the canine cases. Despite morphological alterations detected with the help of sonography or CT, there were no significant increases in a- amylase and lipase in cats. Following computed tomography the pancreas of 10 animals was examined pathohistologically. With the exception of 2 cases the computed tomographic results correlated with the pathohistological findings. In conclusion, computed tomography (CT) proved to be a valuable method to evaluate the localization, the full extent and the seriousness of pancreatic lesions. (author)

  4. Computed tomographic diagnosis of abdominal abscess in childhood

    International Nuclear Information System (INIS)

    Kuhn, J.P.; Berger, P.E.

    1980-01-01

    Twenty-eight children suspected clinically of having an abdominal abscess were examined by CT. Eighteen had gallium 67 citrate scans and 22 had ultrasound studies. Computed tomography was found to be the most accurate test for diagnosis and evaluation of an abscess and the computed tomographic appearance of abscess is illustrated. However, because of cost factors, radiation dose, and clinical considerations, computed tomography is not always the first modality of choice in evaluating a suspected abdominal abscess [fr

  5. The computed tomographic appearances of cherubism

    International Nuclear Information System (INIS)

    Bianchi, S.D.; Boccardi, A.; Mela, F.; Romagnoli, R.

    1987-01-01

    The computed tomographic (CT) aspects of six cases of cherubism are described. Through its optimal representation of the lesions, CT enabled certain characteristics of this disease to be substantiated, namely, limitation of the process to the bones of the jaw and primarily superficial development of the mandibular lesions, coupled with an unusual mandibular condylar impairment. Moreover, the composition of this series permitted investigation of the condition in its several stages of progression. (orig.)

  6. TomoBank: a tomographic data repository for computational x-ray science

    Science.gov (United States)

    De Carlo, Francesco; Gürsoy, Doğa; Ching, Daniel J.; Joost Batenburg, K.; Ludwig, Wolfgang; Mancini, Lucia; Marone, Federica; Mokso, Rajmund; Pelt, Daniël M.; Sijbers, Jan; Rivers, Mark

    2018-03-01

    There is a widening gap between the fast advancement of computational methods for tomographic reconstruction and their successful implementation in production software at various synchrotron facilities. This is due in part to the lack of readily available instrument datasets and phantoms representative of real materials for validation and comparison of new numerical methods. Recent advancements in detector technology have made sub-second and multi-energy tomographic data collection possible (Gibbs et al 2015 Sci. Rep. 5 11824), but have also increased the demand to develop new reconstruction methods able to handle in situ (Pelt and Batenburg 2013 IEEE Trans. Image Process. 22 5238-51) and dynamic systems (Mohan et al 2015 IEEE Trans. Comput. Imaging 1 96-111) that can be quickly incorporated in beamline production software (Gürsoy et al 2014 J. Synchrotron Radiat. 21 1188-93). The x-ray tomography data bank, tomoBank, provides a repository of experimental and simulated datasets with the aim to foster collaboration among computational scientists, beamline scientists, and experimentalists and to accelerate the development and implementation of tomographic reconstruction methods for synchrotron facility production software by providing easy access to challenging datasets and their descriptors.

  7. The CDD system in computed tomographic diagnosis of diverticular disease

    International Nuclear Information System (INIS)

    Pustelnik, Daniel; Elsholtz, Fabian Henry Juergen; Hamm, Bernd; Niehues, Stefan Markus; Bojarski, Christian

    2017-01-01

    Purpose cation in computed tomographic diagnosis and briefly recapitulates its targeted advantages over preliminary systems. Primarily, application of the CDD in computed tomography diagnostics is described. Differences with respect to the categories of the older systems are pointed out on the level of each CDD type using imaging examples. The presented images are derived from our institute according to the S2k criteria. Literature was researched on PubMed. Results The CDD constitutes an improvement compared to older systems for categorizing the stages of diverticular disease. It provides more discriminatory power on the descriptive-morphological level and defines as well as differentiates more courses of the disease. Furthermore, the categories translate more directly into state-of-the-art decision-making concerning hospitalization and therapy. The CDD should be applied routinely in the computed tomographic diagnosis of diverticular disease. Typical imaging patterns are presented.

  8. Computed tomographic study of 50 patients with hypodense hepatic injuries in childhood

    International Nuclear Information System (INIS)

    Pereira, Ines Minniti Rodrigues; Alvares, Beatriz Regina; Baracat, Jamal; Martins, Daniel Lahan; Pereira, Ricardo Minniti Rodrigues

    2006-01-01

    Objective: To describe the different tomographic findings in hypodense hepatic lesions in children and its differential diagnosis. Materials and methods: computed tomographic studies were obtained from 50 patients (age range: 0-16 years) with low-density liver lesions previously diagnosed by ultrasound. Images were made before and after administration of intravenous contrast medium. Image findings were analyzed and afterwards correlated with anatomopathological diagnosis. Results: forty-seven of 50 cases were confirmed, 30 by anatomopathological diagnosis. Most of then were benign lesions, hemangioma in 20%. Such lesions presented a homogeneous contrast absorption, mainly at the delayed phase, differing from malignant lesions. Metastasis was the most frequently found malignant lesion (18%). Conclusion: computed tomographic study is of great value in complementing the diagnosis of hypodense hepatic lesions in children, and must follow ultrasound diagnosis as a routine procedure. (author)

  9. Computer tomographic examinations in epilepsy

    International Nuclear Information System (INIS)

    De Villiers, J.F.K.

    1984-01-01

    Epileptic patients that was examined at the Universitas Hospital (Bloemfontein) by means of computerized tomography for the period July 1978 - December 1980, are divided into two groups: a) Patients with general epilepsy of convulsions - 507; b) Patients with vocal or partial epilepsy - 111. The method of examination and the results for both general and vocal epilepsy are discussed. A degenerative state was found in 35% of the positive computer tomographic examinations in general epilepsy and 22% of the positive examinations for vocal epilepsy. The purpose of the article was to explain the circumstances that can be expected when a epileptic patient is examined by means of computerized tomography

  10. Ovarian metastases: Computed tomographic appearances

    International Nuclear Information System (INIS)

    Megibow, A.J.; Hulnick, D.H.; Bosniak, M.A.; Balthazar, E.J.

    1985-01-01

    Computed tomographic scans of 34 patients with ovarian metastases were reviewed to assess the radiographic appearances and to correlate these with the primary neoplasms. Primary neoplasms were located in the colon (20 patients), breast (six), stomach (five), small bowel (one), bladder (one), and Wilms tumor of the kidney (one). The radiographic appearance of the metastatic lesions could be described as predominantly cystic (14 lesions), mixed (12 lesions), or solid (seven lesions). The cystic and mixed lesions tended to be larger in overall diameter than the solid. The metastases from gastric carcinoma appeared solid in four of five cases. The metastases from the other neoplasms had variable appearances simulating primary ovarian carcinoma

  11. Computed tomographic investigations on intraventricular hematomas

    International Nuclear Information System (INIS)

    Laber-Szillat, S.

    1982-01-01

    This work investigated in 106 patients with intraventricular hematomas all the known factors which can have an influence on prognosis: age, sex, anamnesis of the patients, size, extent and localization of the intracranial bleeding, underlying angiopathy and differences between arterial and venous and spontaneous and traumatic bleedings. It was shown that the state of mind was the deciding prognostic factor, whereby viligance was the cumulative expression of all other investigated influences. A computed tomography (CT) examination is deciding in the question of operative hydrocephalus care. In 13 patients it was further shown, how clearly CT results and brain dissection allowed themselves to be compared. The computed tomographic examination method is best suited to achieve even physiological and more extensive prognostic possibilities. (orig.) [de

  12. Tomographic anthropomorphic models. Pt. 2. Organ doses from computed tomographic examinations in paediatric radiology

    International Nuclear Information System (INIS)

    Zankl, M.; Panzer, W.; Drexler, G.

    1993-11-01

    This report provides a catalogue of organ dose conversion factors resulting from computed tomographic (CT) examinations of children. Two radiation qualities and two exposure geometries were simulated as well as the use of asymmetrical beams. The use of further beam shaping devices was not considered. The organ dose conversion factors are applicable to babies at the age of ca. 2 months and to children between 5 and 7 years but can be used for other ages as well with the appropriate adjustments. For the calculations, the patients were represented by the GSF tomographic anthropomorphic models BABY and CHILD. The radiation transport in the body was simulated using a Monte Carlo method. The doses are presented as conversion factors of mean organ doses per air kerma free in air on the axis of rotation. Mean organ dose conversion factors are given per organ and per scanned body section of 1 cm height. The mean dose to an organ resulting from a particular CT examination can be estimated by summing up the contributions to the organ dose from all relevant sections. To facilitate the selection of the appropriate sections, a table is given which relates the tomographic models' coordinates to certain anatomical landmarks in the human body. (orig.)

  13. Design and applications of Computed Industrial Tomographic Imaging System (CITIS)

    Energy Technology Data Exchange (ETDEWEB)

    Ramakrishna, G S; Kumar, Umesh; Datta, S S [Bhabha Atomic Research Centre, Bombay (India). Isotope Div.

    1994-12-31

    This paper highlights the design and development of a prototype Computed Tomographic (CT) imaging system and its software for image reconstruction, simulation and display. It also describes results obtained with several test specimens including Dhruva reactor uranium fuel assembly and possibility of using neutrons as well as high energy x-rays in computed tomography. 5 refs., 4 figs.

  14. Computed tomographic determination of tracheal dimensions in children and adolescents

    International Nuclear Information System (INIS)

    Griscom, N.T.

    1982-01-01

    A computed tomographic system for determining the internal diameters, cross-sectional area, and length of the trachea in children and adolescents was developed. Intraluminal volumes were calculated from these measurements.The results of 18 analyses are reported

  15. Preexisting Dentinal Microcracks in Nonendodontically Treated Teeth: An Ex Vivo Micro-computed Tomographic Analysis.

    Science.gov (United States)

    PradeepKumar, Angambakkam Rajasekaran; Shemesh, Hagay; Chang, Jeffrey Wen-Wei; Bhowmik, Ahendita; Sibi, Swamy; Gopikrishna, Velayutham; Lakshmi-Narayanan, Lakshmikanthanbharathi; Kishen, Anil

    2017-06-01

    This study evaluated the prevalence, location, and pattern of preexisting dentinal microcracks in roots of extracted teeth without endodontic treatment in patients from 2 age groups using micro-computed tomographic imaging. Six hundred thirty-three nonendodontically treated teeth extracted using an atraumatic procedure because of reasons unrelated to this study were collected and divided based on the patient age. Teeth were scanned with micro-computed tomographic imaging (resolution of 26.7 μm) to examine the presence of preexisting dentinal microcracks in roots. The characteristic features of preexisting dentinal microcracks determined were location, extent, length, and coronoapical distribution. Chi-square bivariate analysis was performed to assess the association between various parameters. Forty-five of 633 nonendodontically treated teeth exhibited preexisting microcracks in roots with a prevalence of 7.1%. The prevalence of preexisting microcracks was found to be 8.3% in older patients (40-70 years) compared with 3.7% in younger patients (20-39 years) (P < .050). A significant association was found between the preexisting microcracks in mandibular teeth (10.3%) when compared with maxillary teeth (2.9%) (P < .001). All preexisting microcracks were located mesiodistally; 66% occurred in the cervical and middle thirds of root. Only 33% of the preexisting microcracks were complete in nature, showing canal involvement. Complete dentinal microcracks exhibited a mean length of 6.9 mm, whereas incomplete cracks had a mean length of 3.75 mm (P < .001). Preexisting dentinal microcracks in roots of nonendodontically treated teeth occurred more often in older patients (40-70 years) in the mesiodistal direction. They were predominantly found in the cervical and middle thirds of root and were more likely to be incomplete in nature. Copyright © 2017 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  16. Precision tomographic analysis of reactor fuels

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Yong Deok; Lee, Chang Hee; Kim, Jong Soo; Jeong, Jwong Hwan; Nam, Ki Yong

    2001-03-01

    For the tomographical assay, search of current status, analysis of neutron beam characteristics, MCNP code simulation, sim-fuel fabrication, neutron experiment for sim-fuel, multiaxes operation system design were done. In sensitivity simulation, the reconstruction results showed the good agreement. Also, the scoping test at ANL was very helpful for actual assay. Therefore, the results are applied for HANARO tomographical system setup and consecutive next research.

  17. Precision tomographic analysis of reactor fuels

    International Nuclear Information System (INIS)

    Lee, Yong Deok; Lee, Chang Hee; Kim, Jong Soo; Jeong, Jwong Hwan; Nam, Ki Yong

    2001-03-01

    For the tomographical assay, search of current status, analysis of neutron beam characteristics, MCNP code simulation, sim-fuel fabrication, neutron experiment for sim-fuel, multiaxes operation system design were done. In sensitivity simulation, the reconstruction results showed the good agreement. Also, the scoping test at ANL was very helpful for actual assay. Therefore, the results are applied for HANARO tomographical system setup and consecutive next research

  18. Computed tomographic findings in manifesting carriers of Duchenne muscular dystrophy

    NARCIS (Netherlands)

    de Visser, M.; Verbeeten, B.

    1985-01-01

    Clinical and computed tomographic (CT) findings in 3 manifesting carriers of Duchenne muscular dystrophy are reported. CT proved to be an important adjunct to the clinical examination: in all our 3 cases a decrease in density was found in various non-paretic muscles

  19. Permeability Surface of Deep Middle Cerebral Artery Territory on Computed Tomographic Perfusion Predicts Hemorrhagic Transformation After Stroke.

    Science.gov (United States)

    Li, Qiao; Gao, Xinyi; Yao, Zhenwei; Feng, Xiaoyuan; He, Huijin; Xue, Jing; Gao, Peiyi; Yang, Lumeng; Cheng, Xin; Chen, Weijian; Yang, Yunjun

    2017-09-01

    Permeability surface (PS) on computed tomographic perfusion reflects blood-brain barrier permeability and is related to hemorrhagic transformation (HT). HT of deep middle cerebral artery (MCA) territory can occur after recanalization of proximal large-vessel occlusion. We aimed to determine the relationship between HT and PS of deep MCA territory. We retrospectively reviewed 70 consecutive acute ischemic stroke patients presenting with occlusion of the distal internal carotid artery or M1 segment of the MCA. All patients underwent computed tomographic perfusion within 6 hours after symptom onset. Computed tomographic perfusion data were postprocessed to generate maps of different perfusion parameters. Risk factors were identified for increased deep MCA territory PS. Receiver operating characteristic curve analysis was performed to calculate the optimal PS threshold to predict HT of deep MCA territory. Increased PS was associated with HT of deep MCA territory. After adjustments for age, sex, onset time to computed tomographic perfusion, and baseline National Institutes of Health Stroke Scale, poor collateral status (odds ratio, 7.8; 95% confidence interval, 1.67-37.14; P =0.009) and proximal MCA-M1 occlusion (odds ratio, 4.12; 95% confidence interval, 1.03-16.52; P =0.045) were independently associated with increased deep MCA territory PS. Relative PS most accurately predicted HT of deep MCA territory (area under curve, 0.94; optimal threshold, 2.89). Increased PS can predict HT of deep MCA territory after recanalization therapy for cerebral proximal large-vessel occlusion. Proximal MCA-M1 complete occlusion and distal internal carotid artery occlusion in conjunction with poor collaterals elevate deep MCA territory PS. © 2017 American Heart Association, Inc.

  20. Direct computation of harmonic moments for tomographic reconstruction

    International Nuclear Information System (INIS)

    Nara, Takaaki; Ito, Nobutaka; Takamatsu, Tomonori; Sakurai, Tetsuya

    2007-01-01

    A novel algorithm to compute harmonic moments of a density function from its projections is presented for tomographic reconstruction. For projection p(r, θ), we define harmonic moments of projection by ∫ π 0 ∫ ∞ -∞ p(r,θ)(re iθ ) n drd θ and show that it coincides with the harmonic moments of the density function except a constant. Furthermore, we show that the harmonic moment of projection of order n can be exactly computed by using n+ 1 projection directions, which leads to an efficient algorithm to reconstruct the vertices of a polygon from projections.

  1. Computed tomographic study in children with microcephaly

    International Nuclear Information System (INIS)

    Ito, Masatoshi; Okuno, Takehiko; Mikawa, Haruki

    1989-01-01

    Computed tomographic (CT) brain scanning was performed on fifty-eight infants and children with microcephaly. CT scans were useful for detecting unsuspected brain lesions and for diagnosing underlying diseases. The head size did not correlate with the CT findings, the degree of mental retardation, or the existence of motor disturbance or epilepsy. On the other hand, the CT findings were correlated with the degree of mental retardation, and the existence of motor disturbance or epilepsy. CT scans were useful for determining the prognosis of the microcephaly. (author)

  2. The Use of Chest Computed Tomographic Angiography in Blunt Trauma Pediatric Population.

    Science.gov (United States)

    Hasadia, Rabea; DuBose, Joseph; Peleg, Kobi; Stephenson, Jacob; Givon, Adi; Kessel, Boris

    2018-02-05

    Blunt chest trauma in children is common. Although rare, associated major thoracic vascular injuries (TVIs) are lethal potential sequelae of these mechanisms. The preferred study for definitive diagnosis of TVI in stable patients is computed tomographic angiography imaging of the chest. This imaging modality is, however, associated with high doses of ionizing radiation that represent significant carcinogenic risk for pediatric patients. The aim of the present investigation was to define the incidence of TVI among blunt pediatric trauma patients in an effort to better elucidate the usefulness of computed tomographic angiography use in this population. A retrospective cohort study was conducted including all blunt pediatric (age blunt trauma victims, 119,821patients were younger than 14 years. Twelve (0.0001%, 12/119821) of these children were diagnosed with TVI. The most common mechanism in this group was pedestrian hit by a car. Mortality was 41.7% (5/12). Thoracic vascular injury is exceptionally rare among pediatric blunt trauma victims but does contribute to the high morbidity and mortality seen with blunt chest trauma. Computed tomographic angiography, with its associated radiation exposure risk, should not be used as a standard tool after trauma in injured children. Clinical protocols are needed in this population to minimize radiation risk while allowing prompt identification of life-threatening injuries.

  3. Bone densitometry with the computer tomograph

    International Nuclear Information System (INIS)

    Weiss, T.

    1978-01-01

    This work tests the usefulness of the EMI head scanner MARK I for a quantitative detection of ossary mineral content. Twenty-three concentration levels of a aqueous K 2 HPO 4 -solution were positioned by means of a special clamping device at the EMI-scanner and examined at tubevoltages of 100, 120 and 140 kV. This produces an almost linear dependence between CT-unit and sample concentration, whereby it shows that the measured special element densities of samples with the same densities vary in dependence with the voltage. The examination of an anotomical fore-arm preperate served as a statement for the reproductability of computer tomographic densitometry at non-moving biological objects. The test of reproductability of bone densitometry measurements under clinical conditions was made on the occation of the six time examinations of the right hand fore-arm bone of a young dummy. Furthermore densitometric examination were made at the fore-arm shelton of 40 long-time dialysis patients in the age levels between 17 and 67 years. The reproductability of the technique presented here is at least not better with the EMI-head-scanner MARK I used here. A change is possible by using the new whole body tomographs. (orig./MG) [de

  4. Analysis of computed tomographic manifestations of primary lung cancer by histologic types

    International Nuclear Information System (INIS)

    Kim, Kyo Yeoun; Choe, Kyu Ok

    1988-01-01

    It is well known that primary lung cancer is one of the most common malignancies in Korea. With respect to the histologic type, primary lung carcinoma manifests itself in a number of different ways. The authors analyzed the computed tomographic (C-T) findings of 183 cases of pathologically confirmed primary lung cancer from 1983 to Aug. 1987 without prior information of histologic types. The results are as follows. 1. The distribution of histologic types of primary lung cancer was as follows: epidermoid carcinoma, 96 cases (52.5%); adenocarcinoma, 43 cases (23.5%); undifferentiated large cell carcinoma, 17 cases (9.2%) and undifferentiated small cell carcinoma, 27 cases (14.8%). 2. The male to female ratio was 3.9:1, the highest ratio occurring in undifferentiated small cell carcinoma 12.5:1 and the lowest ratio in adenocarcinoma 1.1:1 where there was no significant difference in the male to female ratio. 3. Chest computed tomographic findings by histologic type were as follows: (a) Epidermoid carcinoma (96 cases): The central type was the most prevalent (52 cases) with an incidence of 54%. Major air way obstruction was most frequently encountered in this type and was complete in 60% of the cases and partial in 25%. The incidence of cavitating malignancy was 10%, more common than other histologica types. (b) Adenocarcinoma (43 cases): The peripheral type was the most prevalent (28 cases) with an incidence of 63%. Lung to lung metastasis was 23%, more common than other histologic types. (c) Undifferentiated large cell carcinoma (17 cases): The highest incidence occurred in the peripheral type, 9 cases (53%). Chest wall involvement was 12%, more common than other histologic types. (d) Undifferentiated small cell carcinoma (27 cases): The central type (19 cases) presented the highest incidence (70%). Major air way obstruction was noted less severe than epidermoid carcinoma: complete 33%, partial 63%. The incidence of pericardial effusion and/or thickening was 18

  5. Computer tomographic investigation of ancient Egyptian mummies

    Energy Technology Data Exchange (ETDEWEB)

    Huebner, K H; Pahl, W M

    1981-08-01

    Radiological and computer tomographic examinations of Egyptian mummies have been carried out at the Institute of Anthropology and Human Genetics from 1975 to 1978. These have demonstrated the value of CT in medical archaeology. It enables one to study the soft tissues, the skin (if bandaged), the muscles and any organs retained in situ for magical or religious reason. Measurements of attenuation values indicate the materials which were used for mummifying the skin and organs. Characteristic examples are described and the early results of these examinations are discussed.

  6. Computer tomographic investigation of ancient Egyptian mummies

    International Nuclear Information System (INIS)

    Huebner, K.H.; Pahl, W.M.; Tuebingen Univ.

    1981-01-01

    Radiological and computer tomographic examinations of Egyptian mummies have been carried out at the Institute of Anthropology and Human Genetics from 1975 to 1978. These have demonstrated the value of CT in medical archaeology. It enables one to study the soft tissues, the skin (if bandaged), the muscles and any organs retained in situ for magical or religious reason. Measurements of attenuation values indicate the materials which were used for mummifying the skin and organs. Characteristic examples are described and the early results of these examinations are discussed. (orig.) [de

  7. E-learn Computed Tomographic Angiography

    DEFF Research Database (Denmark)

    Havsteen, Inger; Christensen, Anders; Nielsen, Jens K

    2012-01-01

    BACKGROUND: Computed tomographic angiography (CTA) is widely available in emergency rooms to assess acute stroke patients. To standardize readings and educate new readers, we developed a 3-step e-learning tool based on the test-teach-retest methodology in 2 acute stroke scenarios: vascular...... occlusion and "spot sign" in acute intracerebral hemorrhage. We hypothesized that an e-learning program enhances reading skills in physicians of varying experience. METHODS: We developed an HTML-based program with a teaching segment and 2 matching test segments. Tests were taken before and after...... sign correctly 69% before versus 92% after teaching (P = .009) and reported a median self-perceived diagnostic certainty of 50% versus 75% (P = .030). Self-perceived diagnostic certainty revealed no significant increase for vascular occlusion. CONCLUSIONS: The e-learning program is a useful educational...

  8. Dental computed tomographic imaging as age estimation: morphological analysis of the third molar of a group of Turkish population.

    Science.gov (United States)

    Cantekin, Kenan; Sekerci, Ahmet Ercan; Buyuk, Suleyman Kutalmis

    2013-12-01

    Computed tomography (CT) is capable of providing accurate and measurable 3-dimensional images of the third molar. The aims of this study were to analyze the development of the mandibular third molar and its relation to chronological age and to create new reference data for a group of Turkish participants aged 9 to 25 years on the basis of cone-beam CT images. All data were obtained from the patients' records including medical, social, and dental anamnesis and cone-beam CT images of 752 patients. Linear regression analysis was performed to obtain regression formulas for dental age calculation with chronological age and to determine the coefficient of determination (r) for each sex. Statistical analysis showed a strong correlation between age and third-molar development for the males (r2 = 0.80) and the females (r2 = 0.78). Computed tomographic images are clinically useful for accurate and reliable estimation of dental ages of children and youth.

  9. Evaluation of paranasal sinus mucosa in coal worker's pneumoconiosis - A computed tomographic study

    Energy Technology Data Exchange (ETDEWEB)

    Ozdemir, H.; Altin, R.; Mahmutyazicioglu, K.; Kart, L.; Uzun, L.; Savranlar, A.; Davcanci, H.; Gundogdu, S. [Zonguldak Karaelmas University, Zonguldak (Turkey). School of Medicine

    2004-09-01

    Objective: To evaluate by computed tomographic scanning the paranasal mucosal changes of coal workers with and without pneumoconiosis. Methods: Examination of images and scores from paranasal computed tomographic scans. The study participants were 26 coal workers with pneumoconiosis, 29 coal workers without pneumoconiosis, and 20 controls. All were men. The extent and patterns of inflamatory paranasal sinus disease were evaluated on computed, tomographic scans by 2 radiologists using the terminology and definitions of Newman and associates. Results: Interobserver agreement for the presence of abnormalities was from good to excellent (K, 0.63-0.89). The mucosal scores of individuals and groups were higher for coal workers than for control subjects. Both scores were significantly higher in the pneumoconiosis group than in the 2 other groups. Conclusions: This study shows that paranasal sinuses were affected more severely in coal workers than in control subjects. In coal workers with pneumoconiosis, the affection was most severe. The relationship between coal dust exposure and paranasal mucosal changes needs further study.

  10. Computer tomographic and sonographic diagnosis of echinococcus

    Energy Technology Data Exchange (ETDEWEB)

    Schulze, K.; Huebener, K.H.; Klott, K.; Jenss, H.; Baehr, R. (Tuebingen Univ. (Germany, F.R.). Medizinisches Strahleninstitut und Roentgenabteilung; Tuebingen Univ. (Germany, F.R.). Medizinische Klinik; Tuebingen Univ. (Germany, F.R.). Chirurgische Klinik und Poliklinik)

    1980-05-01

    In 33 patients (18 cystic echinococci, 15 alveolar) both methods produced the following findings which could be correlated with the pathological results: single or multi-centric lesions, sharp or indefinite demarkation and abnormalities in the shape and size of the liver. The sonographic findings were analysed with respect to the echo characteristics, whereas the computer tomographically demonstrated lesions were examined densitometrically in order to show calcification. Both methods demonstrate the pathological changes satisfactorily. Computer tomography is more effective in alveolar echinococcus lesions by showing the different types of calcification, whereas sonography provides a more accurate picture of the internal structure of the cysts in cystic echinococcus. Comparison of the methods in 19 patients examined by both showed a high accuracy in each method, but sonography was relatively poor in demonstrating lesions in the spleen.

  11. On the computed tomographic diagnosis of pulmonary nodules

    International Nuclear Information System (INIS)

    Higashi, Yuuichirou

    1988-01-01

    Computed tomography (CT) was used to examine 53 pulmonary nodules which were considered not definitely calcified on plain radiographs or conventional tomograms. An average CT number was calculate for each lesion. For the primary lung cancers, the average CT number was 36 HU with a standard deviation of 6.6 HU, while the benign lesions had the mean CT number of 69 HU, with a standard deviation of 42.8 HU. The mean CT number separating lung malignancies from benign lesions was 78.8 HU. To evaluate the attenuation values within each nodule, iso-CT value map was obtained by using Siemens therapy planning system, MEVAPLAN. Nodules were classified into five categories, Type I to V. All of three nodules classified as Type IV were benign. Iso-CT value map was effective in establishing the benignancy of nodules. The quantitative computed tomographic analysis of pulmonary nodules was evaluated by dual-energy CT. Dual-energy CT has the potential to eliminate the effect of spectral hardening by use of monoenergic images derived from dual-kV data and to separate high CT numbers due to calcium from those due to high density organic material. (author)

  12. ULTRASOUND AND COMPUTED TOMOGRAPHIC DIAGNOSIS OF OPTIC NERVE TUMORS

    Directory of Open Access Journals (Sweden)

    S. V. Saakyan

    2012-01-01

    Full Text Available A comprehensive examination was made in 93 patients, including 18 children, with tumors of the optic nerve (ON. Duplex ultrasound scanning was performed in 39 patients, of them there were 11 patients with ON gliomas and 28 with ON meningiomas. The specific computed tomographic and echographic signs of ON glioma and meningiomas were detected. The studies have shown that duplex ultrasound scanning and structural computed tomography of orbital sockets are highly informative complementary imaging procedures for ON tumors, which permits one to make their correct diagnosis, to specify surgical volume, and to plan adequate treatment.

  13. Analysis of factors influencing the integrated bolus peak timing in contrast-enhanced brain computed tomographic angiography

    International Nuclear Information System (INIS)

    Son, Soon Yong; Choi, Kwan Woo; Jeong, Hoi Woun; Jang, Seo Goo; Jung, Jae Young; Yun, Jung Soo; Kim, Ki Won; Lee, Young Ah; Son, Jin Hyun; Min, Jung Whan

    2016-01-01

    The objective of this study was to analyze the factors influencing integrated bolus peak timing in contrast- enhanced computed tomographic angiography (CTA) and to determine a method of calculating personal peak time. The optimal time was calculated by performing multiple linear regression analysis, after finding the influence factors through correlation analysis between integrated peak time of contrast medium and personal measured value by monitoring CTA scans. The radiation exposure dose in CTA was 716.53 mGy·cm and the radiation exposure dose in monitoring scan was 15.52 mGy (2 - 34 mGy). The results were statistically significant (p < .01). Regression analysis revealed, a -0.160 times decrease with a one-step increase in heart rate in male, and -0.004, -0.174, and 0.006 times decrease with one-step in DBP, heart rate, and blood sugar, respectively, in female. In a consistency test of peak time by calculating measured peak time and peak time by using the regression equation, the consistency was determined to be very high for male and female. This study could prevent unnecessary dose exposure by encouraging in clinic calculation of personal integrated peak time of contrast medium prior to examination

  14. Computer tomographic evaluation of digestive tract non-Hodgkin lymphomas.

    Science.gov (United States)

    Lupescu, Ioana G; Grasu, Mugur; Goldis, Gheorghe; Popa, Gelu; Gheorghe, Cristian; Vasilescu, Catalin; Moicean, Andreea; Herlea, Vlad; Georgescu, Serban A

    2007-09-01

    Computer Tomographic (CT) study is crucial for defining distribution, characteristics and staging of primary gastrointestinal lymphomas. The presence of multifocal sites, the wall thickening with diffuse infiltration of the affected gastrointestinal (GI) segment in association with regional adenopathies, permit the orientation of the CT diagnosis for primary GI lymphomas. The gold standard for diagnosis remains, in all cases of digestive tract non-Hodgkin lymphomas (NHL), the histological examination, which allows a tissue diagnosis, performed preferably by transmural biopsy.

  15. Computed tomographic findings of hepatocellular carcinoma

    International Nuclear Information System (INIS)

    Jo, In Su; Jong, Woo Yung; Lee, Jong Yul; Choi, Han Yong; Kim, Bong Ki

    1987-01-01

    With Development of Computed Tomography, detection of the Hepatocellular Carcinoma are easily performed and frequently used in the world. During 15 months, from December 1985 to February 1987, 59 patients with hepatocellular carcinoma were evaluated with computed tomography in department of radiology at Wallace Memorial Baptist Hospital. The results were as follow: 1. The most prevalent age group was 5th to 7th decades, male to female ratio was 4.9:1. 2. Classification with incidence of computed tomographic appearance of the hepatocellular carcinoma were solitary type 28 cases (48%), multinodular type 24 cases (40%), and diffuse type 7 cases (12%), Association with liver cirrhosis was noted in 22 cases (38%). 3. Inhomogenous internal consistency of hepatocellular carcinoma due to central necrosis were 35 cases (60%). Portal vein invasion by hepatocellular carcinoma was noted in 15 cases (25%), and particularly most common in diffuse type 4 cases (55%). 4. On precontrast scan, all hepatocellular carcinoma were seen as area of low density except for 3 cases(0.5%) of near isodensity which turned out to be remarkable low density on postcontrast scan. 5. In solitary type, posterior segment of right lobe was most common site of involvement 12 cases (43%). In diffuse type, bilobar involvement was most common, 6 cases (85%)

  16. Development of x-ray computed tomographic scanner for iron and steel

    International Nuclear Information System (INIS)

    Taguchi, Isamu; Nakamura, Shigeo.

    1985-01-01

    X-ray computed tomography is extensively used in medicine, but has rarely been applied to non-medical purposes. Steel specimens pose particularly difficult problems-very poor transmission of X-rays and the need for high resolving capability. There has thus been no effective tomographic method of examining steel specimens. Due to the growing need for non-destructive, non-contact methods for observing and analyzing the internal conditions of steel microscopically, however, we have developed an X-ray Computed Tomographic Scanner for Steel (CTS) system, specifically for examination of steel specimens. Its major specifications and functions are as follows. Type: the second-generation CT, 8-channels, Scanning method: 6 0 revolution, 30-times traversing, Slice width: 0.5 mm, Resolving capability: 0.25 x 0.25 mm, X-ray source: 420 kV, 3 mA, X-ray detector: BGO scintillator, Standard specimen shape: 50 mm dia., 100 mm high, Measuring time: 10.5 min. Porosity of a stainless steel (SUS 304) bloom was examined three-dimensionally by the CTS system. Corrosion procedure of a steel slab was also examined. (author)

  17. Tomographic phase analysis to detect the site of accessory conduction pathway in Wolff-Parkinson-White syndrome

    International Nuclear Information System (INIS)

    Nakajima, K.; Bunko, H.; Tada, A.; Tonami, N.; Taki, J.; Nanbu, I.; Hisada, K.; Misaki, T.; Iwa, T.

    1984-01-01

    Phase analysis has been applied to Wolff-Parkinson-White syndrome (WPW) to detect the site of accessory conduction pathway (ACP); however, there was a limitation to estimate the precise location of ACP by planar phase analysis. In this study, the authors applied phase analysis to gated blood pool tomography. Twelve patients with WPW who underwent epicardial mapping and surgical division of ACP were studied by both of gated emission computed tomography (GECT) and routine gated blood pool study (GBPS). The GBPS was performed with Tc-99m red blood cells in multiple projections; modified left anterior oblique, right anterior oblique and/or left lateral views. In GECT, short axial, horizontal and vertical long axial blood pool images were reconstructed. Phase analysis was performed using fundamental frequency of the Fourier transform in both GECT and GBPS images, and abnormal initial contractions on both the planar and tomographic phase analysis were compared with the location of surgically confirmed ACPs. In planar phase analysis, abnormal initial phase was identified in 7 out of 12 (58%) patients, while in tomographic phase analysis, the localization of ACP was predicted in 11 out of 12 (92%) patients. Tomographic phase analysis is superior to planar phase images in 8 out of 12 patients to estimate the location of ACP. Phase analysis by GECT can avoid overlap of blood pool in cardiac chambers and has advantage to identify the propagation of phase three-dimensionally. Tomographic phase analysis is a good adjunctive method for patients with WPW to estimate the site of ACP

  18. Tomographic phase analysis to detect the site of accessory conduction pathway in Wolff-Parkinson-White syndrome

    Energy Technology Data Exchange (ETDEWEB)

    Nakajima, K.; Bunko, H.; Tada, A.; Tonami, N.; Taki, J.; Nanbu, I.; Hisada, K.; Misaki, T.; Iwa, T.

    1984-01-01

    Phase analysis has been applied to Wolff-Parkinson-White syndrome (WPW) to detect the site of accessory conduction pathway (ACP); however, there was a limitation to estimate the precise location of ACP by planar phase analysis. In this study, the authors applied phase analysis to gated blood pool tomography. Twelve patients with WPW who underwent epicardial mapping and surgical division of ACP were studied by both of gated emission computed tomography (GECT) and routine gated blood pool study (GBPS). The GBPS was performed with Tc-99m red blood cells in multiple projections; modified left anterior oblique, right anterior oblique and/or left lateral views. In GECT, short axial, horizontal and vertical long axial blood pool images were reconstructed. Phase analysis was performed using fundamental frequency of the Fourier transform in both GECT and GBPS images, and abnormal initial contractions on both the planar and tomographic phase analysis were compared with the location of surgically confirmed ACPs. In planar phase analysis, abnormal initial phase was identified in 7 out of 12 (58%) patients, while in tomographic phase analysis, the localization of ACP was predicted in 11 out of 12 (92%) patients. Tomographic phase analysis is superior to planar phase images in 8 out of 12 patients to estimate the location of ACP. Phase analysis by GECT can avoid overlap of blood pool in cardiac chambers and has advantage to identify the propagation of phase three-dimensionally. Tomographic phase analysis is a good adjunctive method for patients with WPW to estimate the site of ACP.

  19. Alveolar echinococcosis of the liver - computed tomographic findings

    International Nuclear Information System (INIS)

    Merkle, E.; Usadel, S.; Vogel, J.; Kern, P.; Friedrich, J.M.; Brambs, H.J.

    1995-01-01

    In order to ascertain the typical computed tomographic findings of hepatic alveolar echinococcosis, 24 computed tomograms of 19 patients were evaluated. The liver was involved in all cases whereas the diaphragma was infiltrated in 32%, and the retroperioteneal area in 42%. The right liver lobe was affected in 65%. Both before and after intravenous bolus contrast medium administration, the lesions were mainly inhomogeneous and of low density; a masking of the lesions due to the contrast medium administration was not observed; the enhancement pattern was irregular. Calcifications were detected in 96% of the cases, cystic structures in 50%, and cholestasis in 54%. On the basis of the crucial finding of calcifications in combination with the other typical observations, CT seems to be very suitable for the evaluation of hepatic alveolar echinococcosis. (orig.) [de

  20. Spiral Computed Tomographic Imaging Related to Computerized Ultrasonographic Images of Carotid Plaque Morphology and Histology

    DEFF Research Database (Denmark)

    Grønholdt, Marie-Louise M.; Wagner, Aase; Wiebe, Britt M.

    2001-01-01

    Echolucency of carotid atherosclerotic plaques, as evaluated by computerized B-mode ultrasonographic images, has been associated with an increased incidence of brain infarcts on cerebral computed tomographic scans. We tested the hypotheses that characterization of carotid plaques on spiral comput...

  1. Computed tomographic study of hormone-secreting microadenomas

    International Nuclear Information System (INIS)

    Hemminghytt, S.; Kalkhoff, R.K.; Daniels, D.L.; Williams, A.L.; Grogan, J.P.; Haughton, V.M.

    1983-01-01

    A review was made of the computed tomographic (CT) studies of 33 patients with hormone-secreting microadenomas that had been verified by transsphenoidal surgery and endocrinologic evaluation. In previous studies in small series of patients, the CT appearance of pituitary microadenomas has been reported as hypodense, isodense, and hyperdense. In this study, CT showed a region of diminished enhancement and ususally an enlarged pituitary gland in cases of prolactin-secreting adenomas. HGH- or ACTH-secreting adenomas were less consistently hypodense. It is concluded that hypodensity and enlargement in the pituitary gland are the most useful criteria for identification of microadenomas. Some technical factors that may affect the CT appearance of microadenomas and lead to conflicting reports are discussed

  2. Computed tomographic findings of cerebral arterial ectasia

    International Nuclear Information System (INIS)

    Choi, Woo Suk; Ko, Young Ho; Lim, Jae Hoon

    1987-01-01

    The computed tomographic findings of cerebral arterial ectasia in 8 patients, of which 5 cases were angiographically documented, are reported. The ecstatic arteries, located predominantly in the suprasellar and interpeduncular cisterns, appeared as serpignous, tubular structures on the unenhanced scan. The enhanced CT scan demonstrated dense, sharply defined, homogeneous intraluminal enhancement. Until recently, the diagnosis of cerebral arterial ectasia was usually established by angiography. With introduction of CT it has become possible to noninvasively identify and characterize this vascular disorder and its associated intracranial complications. The vertebrobasilar dolichoectasia may be diagnosed by CT as an extra-axial lesion in the cerebellopontine angle. It enhances in a tubular fashion after intravenous injection of contrast.

  3. Development of the Shimadzu computed tomographic scanner SCT-200N

    International Nuclear Information System (INIS)

    Ishihara, Hiroshi; Yamaoka, Nobuyuki; Saito, Masahiro

    1982-01-01

    The Shimadzu Computed Tomographic Scanner SCT-200N has been developed as an ideal CT scanner for diagnosing the head and spine. Due to the large aperture, moderate scan time and the Zoom Scan Mode, any part of the body can be scanned. High quality image can be obtained by adopting the precisely stabilized X-ray unit and densely packed array of 64-detectors. As for its operation, capability of computed radiography (CR) prior to patient positioning and real time reconstruction ensure efficient patient through-put. Details of the SCT-200N are described in this paper. (author)

  4. Computed tomographic diagnosis of calcified inferior vena cava thrombus in a child with Wilm's tumor

    Energy Technology Data Exchange (ETDEWEB)

    Kirks, D R; Ponzi, J W; Korobkin, M

    1980-01-01

    A calcified thrombus in the inferior vena cava of infants and children may be imaged by computed tomography. The precise location of the calcification within the inferior vena cava may be confirmed by computed tomographic scanning during injection of intravenous contrast material.

  5. Use of computed tomography and computed tomographic myelography for assessment of spinal tumoral calcinosis in a dog

    International Nuclear Information System (INIS)

    Ham, L.M. van; Bree, H.J. van; Tshamala, M.; Thoonen, H.

    1995-01-01

    Spinal tumoral calcinosis is reported in a Berner sennenhund puppy. The condition was manifested clinically as a non-ambulatory tetraparesis associated with neck pain. On survey radiographs there was a focal calcified mass at the atlantoaxial articulation. Computed tomography and computed tomographic myelography gave additional information on the extent of the mass and on the degree of spinal cord compression. The mass was removed surgically and the dog made a complete recovery

  6. Cost-effectiveness of computed tomographic colonography screening for colorectal cancer in the medicare population

    NARCIS (Netherlands)

    A.B. Knudsen (Amy); I. Lansdorp-Vogelaar (Iris); C.M. Rutter (Carolyn); J.E. Savarino (James); M. van Ballegooijen (Marjolein); K.M. Kuntz (Karen); A. Zauber (Ann)

    2010-01-01

    textabstractBackground The Centers for Medicare and Medicaid Services (CMS) considered whether to reimburse computed tomographic colonography (CTC) for colorectal cancer screening of Medicare enrollees. To help inform its decision, we evaluated the reimbursement rate at which CTC screening could be

  7. Blunt oesophageal perforation: treatment with surgical exclusion and percutaneous drainage under computed tomographic guidance

    International Nuclear Information System (INIS)

    Vauthey, J.N.; Lerut, J.; Laube, M.; Gertsch, P.

    1992-01-01

    We report a patient with a left thoracic contusion and rupture of the distal oesophagus. Persistent sepsis developed after oesophageal exclusion without closure. Two collection were drained percutaneously under computed tomographic guidance and the sepsis resolved. (11 refs., 1 fig.)

  8. Spontaneous Intracerebral Hemorrhage: Computed Tomographic Characteristics and Outcome

    Directory of Open Access Journals (Sweden)

    Aimara de la Caridad Vergara Santos

    2015-12-01

    Full Text Available Background: strokes are the third leading cause of death among adults and 10-15 % of them are due to spontaneous intracerebral hemorrhage. Objective: to characterize spontaneous intracerebral hemorrhage through computed tomography scan and its outcome. Methods: a case series study was conducted comprising patients diagnosed with spontaneous intracerebral hemorrhage admitted to the Arnaldo Milián Castro Provincial University Hospital in Villa Clara from January 2009 to January 2010. Tomographic variables of interest were derived from evaluation of spontaneous intracerebral hematomas. Results: fifty-nine cases of spontaneous intracerebral hemorrhage were studied, 23 were located in lobar regions, 4 had severe midline shift, and 2 showed volume greater than 80 ml. Eight out of eleven with extension into the ventricular system had an unfavorable outcome. Among those with thalamic hemorrhage, patients with diameter larger than 4cm and extension into the ventricular system died. Patients with putaminal hemorrhage larger than 4 cm and posterior fossa hematoma with hydrocephalus had a poor outcome, as well as most individuals (55 with other mass effects. Most lobar hematomas (14 out of 23 had a satisfactory outcome, unlike cerebellar and brainstem hematomas. Conclusions: tomographic variables that had a negative impact on the outcome were: volume greater than 80 ml, severe midline shift, diameter larger than 4 cm, extension into the ventricular system, hydrocephalus, other signs of mass effect and brainstem location.

  9. Low-dose computed tomographic imaging in orbital trauma

    Energy Technology Data Exchange (ETDEWEB)

    Jackson, A.; Whitehouse, R.W. (Manchester Univ. (United Kingdom). Dept. of Diagnostic Radiology)

    1993-08-01

    The authors review findings in 75 computed tomographic (CT) examinations of 66 patients with orbital trauma who were imaged using a low-radiation-dose CT technique. Imaging was performed using a dynamic scan mode and exposure factors of 120 kVp and 80 mAs resulting in a skin dose of 11 mGy with an effective dose-equivalent of 0.22 mSv. Image quality was diagnostic in all cases and excellent in 73 examinations. Soft-tissue abnormalities within the orbit including muscle adhesions were well demonstrated both on primary axial and reconstructed multiplanar images. The benefits of multiplanar reconstructions are stressed and the contribution of soft-tissue injuries to symptomatic diplopia examined. (author).

  10. Positioning of Nuclear Fuel Assemblies by Means of Image Analysis on Tomographic Data

    International Nuclear Information System (INIS)

    Troeng, Mats

    2005-06-01

    A tomographic measurement technique for nuclear fuel assemblies has been developed at the Department of Radiation Sciences at Uppsala University. The technique requires highly accurate information about the position of the measured nuclear fuel assembly relative to the measurement equipment. In experimental campaigns performed earlier, separate positioning measurements have therefore been performed in connection to the tomographic measurements. In this work, another positioning approach has been investigated, which requires only the collection of tomographic data. Here, a simplified tomographic reconstruction is performed, whereby an image is obtained. By performing image analysis on this image, the lateral and angular position of the fuel assembly can be determined. The position information can then be used to perform a more accurate tomographic reconstruction involving detailed physical modeling. Two image analysis techniques have been developed in this work. The stability of the two techniques with respect to some central parameters has been studied. The agreement between these image analysis techniques and the previously used positioning technique was found to meet the desired requirements. Furthermore, it has been shown that the image analysis techniques offer more detailed information than the previous technique. In addition, its off-line analysis properties reduce the need for valuable measurement time. When utilizing the positions obtained from the image analysis techniques in tomographic reconstructions of the rod-by-rod power distribution, the repeatability of the reconstructed values was improved. Furthermore, the reconstructions resulted in better agreement to theoretical data

  11. Correlation of computed tomographic and magnetic resonance imaging findings in cerebral infartion

    International Nuclear Information System (INIS)

    Komatsubara, Chizuko; Chuda, Moriyoshi; Taka, Toshihiko

    1989-01-01

    We evaluated neurological findings in 75 patients of cerebral infarction, and correlated computed tomographic (CT) and magnetic resonance imaging (MRI) findings. MRI was found to have the advantage when the lesion were multiple, or in the posterior fossa. MRI demonstrates the anatomical details, and lacks the bony artifact, so it is an excellent method for identification of cerebral infarction. (author)

  12. Morphologic analysis of Japanese adult sacroiliac joint using computed tomographic images

    International Nuclear Information System (INIS)

    Pan, Xuanchao; Takayama, Akinori; Shibata, Yasuaki; Ito, Hiromoto

    2003-01-01

    The purpose of this study was to study the relationship of angles in adult sacroiliac joints (SJ) with laterality, age, gender, degeneration, childbearing in different locations. The study was performed in 92 healthy Japanese adult volunteers (46 males and 46 females, aged 21∼86 years) who had no low back complaints. Axial computed tomographic (CT) images were obtained using an X-VIGOR apparatus (Toshiba Medical Inc. Japan). The angle measurements were taken directly using soft National Institutes of Health (NIH) Image 1.61 (Scion Inc. USA). We examined possible factors. Statistical evaluation was calculated using t-test by soft SPSS (SPSS Inc. Japan). Our findings indicated that SJ angles had no relationships with laterality, gender. But from upper part to lower part, the average of SJ angle was 7.61 deg±8.7 deg, 5.16 deg±7.3 deg, -0.85 deg±7.3 deg respectively in the left and 6.56 deg±9.4 deg, 4.10 deg±7.2 deg, -2.30 deg±7.0 deg in the right. The difference is significant between lower part and upper-middle part (P<0.05). Our results provided new anatomic and morphological data for better understandings of SJ in the clinic work. (author)

  13. Gastrointestinal stromal tumors: retrospective analysis of the computer-tomographic aspects.

    Science.gov (United States)

    Lupescu, Ioana G; Grasu, Mugur; Boros, Mirela; Gheorghe, Cristian; Ionescu, Mihnea; Popescu, Irinel; Herlea, Vlad; Georgescu, Serban A

    2007-06-01

    To describe the computer-tomographic (CT) aspects of gastrointestinal stromal tumors (GISTs) in correlation to their histology. The medical records of all patients at our hospital with a histologic diagnosis of GIST between January 2002 and June 2006, and investigated before surgery by CT, were reviewed. Two radiologists with knowledge of the diagnosis reviewed the CT findings. Amongst 15 cases of GISTs, 9 cases involved the stomach and 4 cases the small intestine. Location of the primary tumor could not be determined for 2 of 15 tumors, because of the presence of extensive peritoneal metastases. Most primary tumors were predominantly extraluminal (13 cases) while two were clearly endoluminal. The mean diameter of the primary tumor was 8 cm. The tumor margin was well defined in 12 patients and irregular in 3 cases. Central fluid attenuation was present in 11 tumors, while central gas was seen in two cases. Metastases were seen in 2 cases at presentation and in another 2 patients during follow-up. Spread was exclusive to the liver or peritoneum. Visceral obstruction was absent even in extensive peritoneal metastatic disease. Ascites was an unusual finding. CT plays an important role not only in the detection and the localization but also in the evaluation of the extension and follow-up of theses tumors. Using only CT aspects, we can only suspect the diagnosis to GISTs. Often other soft-tissue tumors with gastrointestinal involvement can mimic GISTs. In all cases histological diagnosis is essential.

  14. Computed tomographic findings in children with spastic diplegia

    International Nuclear Information System (INIS)

    Yokochi, Kenji; Horie, Masayo; Inukai, Kazuhisa; Kito, Hideyuki; Shimabukuro, Satoshi; Kodama, Kazuo.

    1989-01-01

    Computed tomographic findings of 46 children with spastic diplegia examined at nine months to three years of age corrected for preterm births were analyzed. Both the size of the lateral ventricles measured by the width of the anterior horns, and the volume of the extracerebral low-density areas were enlarged in some patiens. Both enlargements did not, however, correlate to the severity of the motor abnormality in the patients. The low-density areas of the periventricular white matter, especially adjacent to the trigone, were reduced in many children, probably due to the atrophy of the cerebral white matter having periventricular leukomalacia. The anterior expansion of the white matter reduction from the trigone corresponded to the severer motor abnormality in the children with spastic diplegia. (author)

  15. Computed tomographic spectrum of intracranial mycosis: correlation with histopathology

    International Nuclear Information System (INIS)

    Whelan, M.A.; Stern, J.; deNapoli, R.A.

    1981-01-01

    Four cases of intracerebral fungal infection are reviewed. The clinical course is outlined, and the computed tomographic (CT) characteristics are analyzed in light of known pathological data. The CT appearance of intracranial mycosis is dependent on the type of fungus as well as the dominant infecting form, i.e., yeast or hyphae. The hyphal form leads predominantly to a CT pattern consistent with vascular occlusion and secondary abscess formation; the yeast form generally results in noncaseating granulomas, which appear on CT scan as nodular enhancing lesions. If the patient survives the acute infective process, these fungal lesions undergo a prolonged subacute phase, and may eventually calcify

  16. Influence of using a single facial vein as outflow in full-face transplantation: A three-dimensional computed tomographic study.

    Science.gov (United States)

    Rodriguez-Lorenzo, Andres; Audolfsson, Thorir; Wong, Corrine; Cheng, Angela; Arbique, Gary; Nowinski, Daniel; Rozen, Shai

    2015-10-01

    The aim of this study was to evaluate the contribution of a single unilateral facial vein in the venous outflow of total-face allograft using three-dimensional computed tomographic imaging techniques to further elucidate the mechanisms of venous complications following total-face transplant. Full-face soft-tissue flaps were harvested from fresh adult human cadavers. A single facial vein was identified and injected distally to the submandibular gland with a radiopaque contrast (barium sulfate/gelatin mixture) in every specimen. Following vascular injections, three-dimensional computed tomographic venographies of the faces were performed. Images were viewed using TeraRecon Software (Teracon, Inc., San Mateo, CA, USA) allowing analysis of the venous anatomy and perfusion in different facial subunits by observing radiopaque filling venous patterns. Three-dimensional computed tomographic venographies demonstrated a venous network with different degrees of perfusion in subunits of the face in relation to the facial vein injection side: 100% of ipsilateral and contralateral forehead units, 100% of ipsilateral and 75% of contralateral periorbital units, 100% of ipsilateral and 25% of contralateral cheek units, 100% of ipsilateral and 75% of contralateral nose units, 100% of ipsilateral and 75% of contralateral upper lip units, 100% of ipsilateral and 25% of contralateral lower lip units, and 50% of ipsilateral and 25% of contralateral chin units. Venographies of the full-face grafts revealed better perfusion in the ipsilateral hemifaces from the facial vein in comparison with the contralateral hemifaces. Reduced perfusion was observed mostly in the contralateral cheek unit and contralateral lower face including the lower lip and chin units. Copyright © 2015 British Association of Plastic, Reconstructive and Aesthetic Surgeons. Published by Elsevier Ltd. All rights reserved.

  17. Computed tomographic findings of progressive supranuclear palsy compared with Parkinson's disease

    Energy Technology Data Exchange (ETDEWEB)

    Yuki, Nobuhiro; Sato, Shuzo; Yuasa, Tatsuhiko; Ito, Jusuke; Miyatake, Tadashi [Niigata Univ. (Japan). School of Dentistry

    1990-10-01

    We investigated computed tomographic (CT) films of 4 pathologically documented cases of progressive supranuclear palsy (PSP) in which the clinical presentations were atypical and compared the findings with those of 15 patients with Parkinson's disease (PD). Dilatation of the third ventricle, atrophy of the midbrain tegmentum, and enlargement of the interpeduncular cistern toward the aqueduct were found to be the characteristic findings in PSP. Thus, radiological findings can be useful when the differential diagnosis between PSP and PD is clinically difficult. (author).

  18. Computed tomographic analysis of vegetable during far infrared radiation drying process

    International Nuclear Information System (INIS)

    Maneechot, P.; Tojo, S.; Watanabe, K.

    2006-01-01

    Far Infrared Radiation (FIR) technology is widely used in the automotive industry to cure painted finishes during manufacturing. FIR drying is used not only in manufacturing but also in agricultural processing such as rice drying. At the present time, FIR drying technology has rarely been used for fruits and vegetables except in research laboratories. In this study, FIR drying and hot air convection drying were compared with respect to energy consumption and time requirement. The internal changes of the agricultural product were also observed during the FIR drying process. A Computed Tomographic (CT) scanner was employed for the observation of the tested material, carrot, and was used to analyze the structural deformation and the internal moisture distribution of the test material. CT data and the hardness of the sample were recorded at regular intervals during the drying experiment. For 200, 400 and 600W FIR drying, the maximum drying rates were 173, 459 and 724%d.b./hr respectively, and the required drying times were 26, 12 and 4.5 hours, respectively. The structure of the carrot sample shrank in accordance with the reduction of moisture content in 200W FIR drying as well as in hot air drying, whereas in 400W and 600W FIR drying the sample was dried without so much deformation

  19. Computer tomographic and angiographic studies of histologically confirmed intrahepatic masses

    International Nuclear Information System (INIS)

    Janson, R.; Lackner, K.; Paquet, K.J.; Thelen, M.; Thurn, P.

    1980-01-01

    The computer tomographic and angiographic findings in 53 patients with intrahepatic masses were compared. The histological findings show that 17 were due to echinococcus, 12 were due to hepatic carcinoma, ten were metastases, five patients had focal nodular hyperplasia, three an alveolar echinococcus and there were three cases with an haemangioma of the liver and a further three liver abscesses. Computer tomography proved superior in peripherally situated lesions, and in those in the left lobe of the liver. Arteriography was better at demonstrating lesions below 2 cm in size, particularly vascular tumours. As a pre-operative measure, angiography is to be preferred since it is able to demonstrate anatomic anomalies and variations in the blood supply, as well as invasion of the portal vein or of the inferior vena cava. (orig.) [de

  20. Computer tomographic and angiographic studies of histologically confirmed intrahepatic masses

    Energy Technology Data Exchange (ETDEWEB)

    Janson, R.; Lackner, K.; Paquet, K.J.; Thelen, M.; Thurn, P.

    1980-06-01

    The computer tomographic and angiographic findings in 53 patients with intrahepatic masses were compared. The histological findings show that 17 were due to echinococcus, 12 were due to hepatic carcinoma, ten were metastases, five patients had focal nodular hyperplasia, three an alveolar echinococcus and there were three cases with an haemangioma of the liver and a further three liver abscesses. Computer tomography proved superior in peripherally situated lesions, and in those in the left lobe of the liver. Arteriography was better at demonstrating lesions below 2 cm in size, particularly vascular tumours. As a pre-operative measure, angiography is to be preferred since it is able to demonstrate anatomic anomalies and variations in the blood supply, as well as invasion of the portal vein or of the inferior vena cava.

  1. Intra-articualr calcaneal fractures: Computed tomographic analysis

    International Nuclear Information System (INIS)

    Rosenberg, Z.S.; Feldman, F.; Singson, R.D.

    1987-01-01

    Computed tomography (CT) analysis of 21 intra-articular calcaneal fractures categorized according to the Essex-Lopresti classification revealed the following distribution: joint depression-type 57%, comminuted type 43%, tongue-type 0%. The posterior calcaneal facet was fractured and/or depressed in 100% of the cases while the medial facet was involved in only 25% of the cases. CT proved superior to plain films by consistently demonstrating additional fracture components within each major category suggesting subclassifications which have potential prognostic value. CT allowed more expeditious handling of acutely injured patients, and improved preoperative planning, postoperative follow-up, and detailed analysis of causes for chronic residual pain. CT further identified significant soft tissue injuries such as peroneal tendon displacement which cannot be delineated on plain films. (orig.)

  2. Results of work of neurological clinic in first year of computer tomograph application

    Energy Technology Data Exchange (ETDEWEB)

    Volejnik, V; Nettl, S; Heger, L [Karlova Univ., Hradec Kralove (Czechoslovakia). Lekarska Fakulta

    1980-11-01

    The results are analyzed of one year's use of a computer tomograph (CT) by a department of neurology. Detailed comparisons with corresponding PEG and CT findings showed the accuracy of CT examinations in the descriptions of the width of the subarachnoid spaces and of the ventricular system. The advantages of CT are assessed from the medical, economic, and ethical points of view.

  3. Results of work of neurological clinic in first year of computer tomograph application

    International Nuclear Information System (INIS)

    Volejnik, V.; Nettl, S.; Heger, L.

    1980-01-01

    The results are analyzed of one year's use of a computer tomograph (CT) by a department of neurology. Detailed comparisons with corresponding PEG and CT findings showed the accuracy of CT examinations in the descriptions of the width of the subarachnoid spaces and of the ventricular system. The advantages of CT are assessed from the medical, economic, and ethical points of view. (author)

  4. Central nervous system leukemia and lymphoma: computed tomographic manifestations

    International Nuclear Information System (INIS)

    Pagani, J.J.; Libshitz, H.I.; Wallace, S.; Hayman, L.A.

    1981-01-01

    Computed tomographic (CT) abnormalities in the brain were identified in 31 of 405 patients with leukemia or lymphoma. Abnormalities included neoplastic masses (15), hemorrhage (nine), abscess (two), other brain tumors (four), and methotrexate leukoencephalopathy (one). CT was normal in 374 patients including 148 with meningeal disease diagnosed by cerebrospinal fluid cytologic examination. Prior to treatment, malignant masses were isodense or of greater density with varying amounts of edema. Increase in size or number of the masses indicated worsening. Response to radiation and chemotherapy was manifested by development of a central low density region with an enhancing rim. CT findings correlated with clinical and cerebrospinal fluid findings. The differential diagnosis of the various abnormalities is considered

  5. Detectability in the presence of computed tomographic reconstruction noise

    International Nuclear Information System (INIS)

    Hanson, K.M.

    1977-01-01

    The multitude of commercial computed tomographic (CT) scanners which have recently been introduced for use in diagnostic radiology has given rise to a need to compare these different machines in terms of image quality and dose to the patient. It is therefore desirable to arrive at a figure of merit for a CT image which gives a measure of the diagnostic efficacy of that image. This figure of merit may well be dependent upon the specific visual task being performed. It is clearly important that the capabilities and deficiencies of the human observer as well as the interface between man and machine, namely the viewing system, be taken into account in formulating the figure of merit. Since the CT reconstruction is the result of computer processing, it is possible to use this processing to alter the characteristics of the displayed images. This image processing may improve or degrade the figure of merit

  6. First experience with a mobile computed tomograph in the USSR

    International Nuclear Information System (INIS)

    Portnoj, L.M.

    1989-01-01

    Utilization experience of mobile computerized tomograph mounted in the bus is presented. Problems concerning staff, selection of medical base institutes etc are considered. Efficiency of mobile computerized tomographes in revealing different diseases is pointed out

  7. Micro-computed Tomographic Analysis of Mandibular Second Molars with C-shaped Root Canals.

    Science.gov (United States)

    Amoroso-Silva, Pablo Andrés; Ordinola-Zapata, Ronald; Duarte, Marco Antonio Hungaro; Gutmann, James L; del Carpio-Perochena, Aldo; Bramante, Clovis Monteiro; de Moraes, Ivaldo Gomes

    2015-06-01

    The goal of the present study was to evaluate the morphometric aspects of the internal anatomy of the root canal system of mandibular second molars with C-shaped canals. Fifty-two extracted second mandibular molars with C-shaped canals, fused roots, and radicular grooves were selected from a Brazilian population. The samples were scanned with a micro-computed tomographic scanner at a voxel size of 19.6 μm. The root canal cross sections were recorded as C1, C2, C3, and C4 root canal configurations according to the modified Melton classification. Morphometric parameters, including the major and minor diameters of the root canals, the aspect ratio, the roundness, and the tridimensional configuration (merging, symmetric, and asymmetric), were evaluated. The 3-dimensional reconstruction images of the teeth indicated an even distribution within the sample. The analysis of the prevalence of the different cross-sectional configurations of the C-shaped molars revealed that these were predominantly of the C4 and C3 configurations (1 mm from the apex) and the C1 and C2 configurations in the cervical third. According to the morphometric parameters, the C1 and the distal aspect of the C2 configurations exhibited the lowest roundness values and higher values for the area, major diameter, and aspect ratio in the apical third. Mandibular molars with C-shaped root canals exhibited similar distributions of symmetric, asymmetric, and merging type canals. The C1 configuration and the distal aspect of the C2 configuration exhibited the highest area values, low roundness values, and large apical diameters. Copyright © 2015 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  8. Verification of computed tomographic estimates of cochlear implant array position: a micro-CT and histologic analysis.

    Science.gov (United States)

    Teymouri, Jessica; Hullar, Timothy E; Holden, Timothy A; Chole, Richard A

    2011-08-01

    To determine the efficacy of clinical computed tomographic (CT) imaging to verify postoperative electrode array placement in cochlear implant (CI) patients. Nine fresh cadaver heads underwent clinical CT scanning, followed by bilateral CI insertion and postoperative clinical CT scanning. Temporal bones were removed, trimmed, and scanned using micro-CT. Specimens were then dehydrated, embedded in either methyl methacrylate or LR White resin, and sectioned with a diamond wafering saw. Histology sections were examined by 3 blinded observers to determine the position of individual electrodes relative to soft tissue structures within the cochlea. Electrodes were judged to be within the scala tympani, scala vestibuli, or in an intermediate position between scalae. The position of the array could be estimated accurately from clinical CT scans in all specimens using micro-CT and histology as a criterion standard. Verification using micro-CT yielded 97% agreement, and histologic analysis revealed 95% agreement with clinical CT results. A composite, 3-dimensional image derived from a patient's preoperative and postoperative CT images using a clinical scanner accurately estimates the position of the electrode array as determined by micro-CT imaging and histologic analyses. Information obtained using the CT method provides valuable insight into numerous variables of interest to patient performance such as surgical technique, array design, and processor programming and troubleshooting.

  9. Development of an electrical impedance computed tomographic two-phase flows analyzer. Annual technical report for program renewal

    Energy Technology Data Exchange (ETDEWEB)

    Jones, O.C.

    1993-05-01

    This progress report details the theoretical development, numerical results, experimental design (mechanical), experimental design (electronic), and experimental results for the research program for the development of an electrical impedance computed tomographic two-phase flow analyzer.

  10. Utility of cervical spinal and abdominal computed tomography in diagnosing occult pneumothorax in patients with blunt trauma: Computed tomographic imaging protocol matters.

    Science.gov (United States)

    Akoglu, Haldun; Akoglu, Ebru Unal; Evman, Serdar; Akoglu, Tayfun; Denizbasi, Arzu; Guneysel, Ozlem; Onur, Ozge; Onur, Ender

    2012-10-01

    Small pneumothoraces (PXs), which are not initially recognized with a chest x-ray film and diagnosed by a thoracic computed tomography (CT), are described as occult PX (OCPX). The objective of this study was to evaluate cervival spine (C-spine) and abdominal CT (ACT) for diagnosing OCPX and overt PX (OVPX). All patients with blunt trauma who presented consecutively to the emergency department during a 26-months period were included. Among all the chest CTs (CCTs) (6,155 patients) conducted during that period, 254 scans were confirmed to have a true PX. The findings in their C-spine CT and ACT were compared with the findings in CCTs. Among these patients, 254 had a diagnosis of PX confirmed with CCT. OCPXs were identified on the chest computed tomographic scan of 128 patients (70.3%), whereas OVPXs were evident in 54 patients (29.7%). Computed tomographic imaging of the C-spine was performed in 74% of patients with OCPX and 66.7% of patients with OVPX trauma. Only 45 (35.2%) cases of OCPX and 42 (77.8%) cases of OVPX were detected by C-spine CT. ACT was performed in almost all patients, and 121 (95.3%) of 127 of these correctly identified an existing OCPX. Sensitivity of C-spine CT and ACT was 35.1% and 96.5%, respectively; specificity was 100% and 100%, respectively. Almost all OCPXs, regardless of intrathoracic location, could be detected by ACT or by combining C-spine and abdominal computed tomographic screening for patients. If the junction of the first and second vertebra is used as the caudad extent, C-spine CT does not have sufficient power to diagnose more than a third of the cases. Diagnostic study, level III.

  11. Costs and clinical outcomes in individuals without known coronary artery disease undergoing coronary computed tomographic angiography from an analysis of Medicare category III transaction codes.

    Science.gov (United States)

    Min, James K; Shaw, Leslee J; Berman, Daniel S; Gilmore, Amanda; Kang, Ning

    2008-09-15

    Multidetector coronary computed tomographic angiography (CCTA) demonstrates high accuracy for the detection and exclusion of coronary artery disease (CAD) and predicts adverse prognosis. To date, opportunity costs relating the clinical and economic outcomes of CCTA compared with other methods of diagnosing CAD, such as myocardial perfusion single-photon emission computed tomography (SPECT), remain unknown. An observational, multicenter, patient-level analysis of patients without known CAD who underwent CCTA or SPECT was performed. Patients who underwent CCTA (n = 1,938) were matched to those who underwent SPECT (n = 7,752) on 8 demographic and clinical characteristics and 2 summary measures of cardiac medications and co-morbidities and were evaluated for 9-month expenditures and clinical outcomes. Adjusted total health care and CAD expenditures were 27% (p cost-efficient alternative to SPECT for the initial coronary evaluation of patients without known CAD.

  12. Pipelining Computational Stages of the Tomographic Reconstructor for Multi-Object Adaptive Optics on a Multi-GPU System

    KAUST Repository

    Charara, Ali; Ltaief, Hatem; Gratadour, Damien; Keyes, David E.; Sevin, Arnaud; Abdelfattah, Ahmad; Gendron, Eric; Morel, Carine; Vidal, Fabrice

    2014-01-01

    called MOSAIC has been proposed to perform multi-object spectroscopy using the Multi-Object Adaptive Optics (MOAO) technique. The core implementation of the simulation lies in the intensive computation of a tomographic reconstruct or (TR), which is used

  13. Comparative validity and reproducibility study of various landmark-oriented reference planes in 3-dimensional computed tomographic analysis for patients receiving orthognathic surgery.

    Science.gov (United States)

    Lin, Hsiu-Hsia; Chuang, Ya-Fang; Weng, Jing-Ling; Lo, Lun-Jou

    2015-01-01

    Three-dimensional computed tomographic imaging has become popular in clinical evaluation, treatment planning, surgical simulation, and outcome assessment for maxillofacial intervention. The purposes of this study were to investigate whether there is any correlation among landmark-based horizontal reference planes and to validate the reproducibility and reliability of landmark identification. Preoperative and postoperative cone-beam computed tomographic images of patients who had undergone orthognathic surgery were collected. Landmark-oriented reference planes including the Frankfort horizontal plane (FHP) and the lateral semicircular canal plane (LSP) were established. Four FHPs were defined by selecting 3 points from the orbitale, porion, or midpoint of paired points. The LSP passed through both the lateral semicircular canal points and nasion. The distances between the maxillary or mandibular teeth and the reference planes were measured, and the differences between the 2 sides were calculated and compared. The precision in locating the landmarks was evaluated by performing repeated tests, and the intraobserver reproducibility and interobserver reliability were assessed. A total of 30 patients with facial deformity and malocclusion--10 patients with facial symmetry, 10 patients with facial asymmetry, and 10 patients with cleft lip and palate--were recruited. Comparing the differences among the 5 reference planes showed no statistically significant difference among all patient groups. Regarding intraobserver reproducibility, the mean differences in the 3 coordinates varied from 0 to 0.35 mm, with correlation coefficients between 0.96 and 1.0, showing high correlation between repeated tests. Regarding interobserver reliability, the mean differences among the 3 coordinates varied from 0 to 0.47 mm, with correlation coefficients between 0.88 and 1.0, exhibiting high correlation between the different examiners. The 5 horizontal reference planes were reliable and

  14. Computed Tomographic Morphometry of the Internal Anatomy of Mandibular Second Primary Molars.

    Science.gov (United States)

    Kurthukoti, Ameet J; Sharma, Pranjal; Swamy, Dinesh Francis; Shashidara, R; Swamy, Elaine Barretto

    2015-01-01

    Need for the study: The most important procedure for a successful endodontic treatment is the cleaning and shaping of the canal system. Understanding the internal anatomy of teeth provides valuable information to the clinician that would help him achieve higher clinical success during endodontic therapy. To evaluate by computed tomography-the internal anatomy of mandibular second primary molars with respect to the number of canals, cross-sectional shape of canals, cross-sectional area of canals and the root dentin thickness. A total of 31 mandibular second primary molars were subjected to computed-tomographic evaluation in the transverse plane, after mounting them in a prefabricated template. The images, thus, obtained were analyzed using De-winter Bio-wizard® software. All the samples demonstrated two canals in the mesial root, while majority of the samples (65.48%) demonstrated two canals in the distal root. The cross-sectional images of the mesial canals demonstrated a round shape, while the distal canals demonstrated an irregular shape. The root dentin thickness was highly reduced on the distal aspect of mesial and mesial aspect of distal canals. The mandibular second primary molars demonstrated wide variation and complexities in their internal anatomy. A thorough understanding of the complexity of the root canal system is essential for understanding the principles and problems of shaping and cleaning, determining the apical limits and dimensions of canal preparations, and for performing successful endodontic procedures. How to cite this article: Kurthukoti AJ, Sharma P, Swamy DF, Shashidara R, Swamy EB. Computed Tomographic Morphometry of the Internal Anatomy of Mandibular Second Primary Molars. Int J Clin Pediatr Dent 2015;8(3):202-207.

  15. Craniofacial fibrous dysplasia: Report of a case using computed tomographic scan diagnosis

    Directory of Open Access Journals (Sweden)

    Nikhil Diwan

    2013-01-01

    Full Text Available Fibro-osseous lesions are benign mesenchymal tumors in which mineralized tissue, blood vessels, and giant cells, in varying proportions, replace normal bone. Although this group of lesions includes reactive lesions, harmatomas, and neoplasms, they cannot be distinguished only on the basis of the histopathology which can only confirm their common fibro-osseous nature. Definitive diagnosis requires thorough radiological evaluation. Computed tomographic images of craniofacial fibrous dysplasia on bone windows may be helpful and allow precise pre-operative diagnosis and surgical planning.

  16. Computed tomographic findings of intracerebral cysticercosis

    Energy Technology Data Exchange (ETDEWEB)

    Hong, Jin Kyo; Lee, Sun Wha; Kim, Ho Kyun; Ahn, Chi Yul [School of Medicine, Kyung-Hee University, Seoul (Korea, Republic of)

    1980-12-15

    Cysticercosis is a parasitic disease in which man serves as the intermediate host of Taenia Solium, the pork tapeworm. The computed tomographic findings of 25 cases of intracerebral cysticercosis proven by pathologic and/or clinical findings during past 2 years were analysed. The results were as follows; 1. The sex was 19 males and 6 females, and 56 percent of the patients were seen in fourth and fifth decades. The most common symptom was epilepsy (72%). 2. The C. T. findings in precontrast study were varied; such as ill defined low density (48%), cystic low density (20%), dilated ventricles (20%), ill defined low density with isodense nodule (18%), cystic low density with isodense mural nodule (12%) and calcification (8%). 3. The areas of involvement were 20 cases (80%) of parenchymal form, 3 cases (12%) of ventricular form and 2 cases (8%) of mixed form. 4. The contrast-enhanced 13 cases were 5 nodular, 5 ring or rim-like and 3 mixed type enhancements, while 12 cases were not enhanced. 5. C.T. scan demonstrated more precise location and extents of cerebral cysticercosis, especially in parenchymal form. It was considered to be important in determination of surgical feasibility and its approach.

  17. Computed tomographic findings of cerebral paragonimiasis

    International Nuclear Information System (INIS)

    Sung, Nak Kwan; Nam, Kyung Jin; Park, Churl Min; Eun, Chung Kie; Lee, Sun Wha

    1983-01-01

    Paragonimiasis is widely distributed in Far East and Southeast Asia, particularly in Korea. The central nervous system is the most frequent location for paragonimiasis outside the lungs. We analyzed the computed tomographic findings of 17 cases which were diagnosed pathologically and clinically as cerebral paragonimiasis. The results were as follows: 1. The ratio of male to female was 10 : 7 and about 88% of cases were under the age of 40 years. 2. The common locations of cerebral paragonimiasis were the occipital (12 cases) and temporal (11 cases) lobes. 3. Precontrast CT findings of cerebral paragonimiasis were low density with calcifications in 6 cases, low and isodensities in 4 cases, mixed densities in 3 cases, only low density in 2 cases and only calcification in 2 cases. Hydrocephalus (7 cases), mass effect (6 cases), atrophic change (6 cases) and cyst formation (3 cases) were associated. 4. The shape of calcifications in CT scan were soap-bubble or ring in 6 cases, nodular or oval in 6 cases, stipple in 4 cases and amorphous conglomerated in 2 cases. 5. The contrast -enhanced 8 cases were 5 ring or rim like, 2 nodular and 1 irregular enhancements, while 9 cases were not enhanced

  18. Implementation of 3D tomographic visualisation through planar ICT data from experimental gamma-ray tomographic system

    International Nuclear Information System (INIS)

    Umesh Kumar; Singh, Gursharan; Ravindran, V.R.

    2001-01-01

    Industrial Computed Tomography (ICT) is one of the latest methods of non-destructive testing and examination. Different prototypes of Computed Industrial Tomographic Imaging System (CITIS) have been developed and experimental data have been generated in Isotope Applications Division. The experimental gamma-rays based tomographic imaging system comprises of beam generator containing approx. 220 GBq (6 Curies) of 137 Cs, a single NaI(Tl) -PMT integral assembly in a thick shielding and associated electronics, stepper motor controlled mechanical manipulator, collimators and required software. CITIS data is normally acquired in one orientation of the sample. It may be sometimes required to view a tomographic plane in a different orientation. Also, 3D visualization may be required with the available 2D data set. All these can be achieved by processing the available data. We have customized some of the routines for this purpose provided IDL (Integrated Data Language) package to suit our requirements. The present paper discusses methodology adopted for this purpose with an illustrative example. (author)

  19. The CDD system in computed tomographic diagnosis of diverticular disease; Das CDD-System in der computertomografischen Diagnostik der Divertikelkrankheit

    Energy Technology Data Exchange (ETDEWEB)

    Pustelnik, Daniel; Elsholtz, Fabian Henry Juergen; Hamm, Bernd; Niehues, Stefan Markus [Charite - Universitaetsmedizin, Berlin (Germany). Inst. of Radiology; Bojarski, Christian [Charite - Universitaetsmedizin, Berlin (Germany). Div. of Gastroenterology, Infectiology and Rheumatology

    2017-08-15

    Purpose cation in computed tomographic diagnosis and briefly recapitulates its targeted advantages over preliminary systems. Primarily, application of the CDD in computed tomography diagnostics is described. Differences with respect to the categories of the older systems are pointed out on the level of each CDD type using imaging examples. The presented images are derived from our institute according to the S2k criteria. Literature was researched on PubMed. Results The CDD constitutes an improvement compared to older systems for categorizing the stages of diverticular disease. It provides more discriminatory power on the descriptive-morphological level and defines as well as differentiates more courses of the disease. Furthermore, the categories translate more directly into state-of-the-art decision-making concerning hospitalization and therapy. The CDD should be applied routinely in the computed tomographic diagnosis of diverticular disease. Typical imaging patterns are presented.

  20. Tuberculosis of the Parotid Gland: Computed Tomographic Findings

    International Nuclear Information System (INIS)

    Wei, Y.; Xiao, J.; Pui, M.H.; Gong, Q.

    2008-01-01

    Background: Tuberculosis (TB) of the parotid gland is rare, even in endemic regions. Approximately 100 cases have been reported in the English literature. The computed tomographic (CT) features, however, have seldom been studied. Purpose: To determine the diagnostic CT features of tuberculosis of the parotid gland. Material and Methods: CT studies of four histologically proven cases of tuberculosis of the parotid gland were retrospectively reviewed. Results: A total of 15 enlarged lymph nodes were found in the superficial lobes of the parotid glands. The nodes were arranged linearly within the gland. Enhancement patterns included homogeneous enhancement (9/15, 60%), homogeneous enhancement with eccentric microcysts (3/15, 20%), and thick-walled rim enhancement with central lucency (3/15, 20%). Thickened adjacent fascial plane and platysma were seen in two patients. Ipsilateral cervical lymphadenopathy was seen in all patients. Conclusion: In patients presenting with unilateral parotid nodules, TB should be considered when linearly arranged enhancing nodules are demonstrated in the superficial lobes of the glands on CT scan

  1. Data and Analysis from a Time-Resolved Tomographic Optical Beam Diagnostic

    International Nuclear Information System (INIS)

    Frayer, Daniel K.; Johnson, Douglas; Ekdahl, Carl

    2010-01-01

    An optical tomographic diagnostic instrument developed for the acquisition of high-speed time-resolved images has been fielded at the Dual-Axis Radiographic Hydrodynamic Test (DARHT) Facility at Los Alamos National Laboratory. The instrument was developed for the creation of time histories of electron-beam cross section through the collection of Cerenkov light. Four optical lines of sight optically collapse an image and relay projections via an optical fiber relay to recording instruments; a tomographic reconstruction algorithm creates the time history. Because the instrument may be operated in an adverse environment, it may be operated, adjusted, and calibrated remotely. The instrument was operated over the course of various activities during and after DARHT commissioning, and tomographic reconstructions reported verifiable beam characteristics. Results from the collected data and reconstructions and analysis of the data are discussed.

  2. Micro-computed Tomographic Analysis of Apical Microcracks before and after Root Canal Preparation by Hand, Rotary, and Reciprocating Instruments at Different Working Lengths.

    Science.gov (United States)

    de Oliveira, Bruna Paloma; Câmara, Andréa Cruz; Duarte, Daniel Amancio; Heck, Richard John; Antonino, Antonio Celso Dantas; Aguiar, Carlos Menezes

    2017-07-01

    This study aimed to compare apical microcrack formation after root canal shaping by hand, rotary, and reciprocating files at different working lengths using micro-computed tomographic analysis. Sixty mandibular incisors were randomly divided into 6 experimental groups (n = 10) according to the systems and working lengths used for the root canal preparation: ProTaper Universal for Hand Use (Dentsply Maillefer, Ballaigues, Switzerland), HyFlex CM (Coltene-Whaledent, Allstetten, Switzerland), and Reciproc (VDW, Munich, Germany) files working at the apical foramen (AF) and 1 mm short of the AF (AF - 1 mm). The teeth were imaged with micro-computed tomographic scanning at an isotropic resolution of 14 μm before and after root canal preparation, and the cross-sectional images generated were assessed to detect microcracks in the apical portion of the roots. Overall, 17 (28.3%) specimens presented microcracks before instrumentation. Apical microcracks were present in 1 (ProTaper Universal for Hand Use), 3 (Hyflex CM), and 2 (Reciproc) specimens when the instrumentation terminated at the AF. When instrumentation was terminated at AF - 1 mm, apical microcracks were detected in 3 (ProTaper Universal for Hand Use) and 4 (Hyflex CM and Reciproc) specimens. All these microcracks detected after root canal preparation were already present before instrumentation, and no new apical microcrack was visualized. For all groups, the number of slices presenting microcracks after root canal preparation was the same as before canal preparation. Root canal shaping with ProTaper Universal for Hand Use, HyFlex CM, and Reciproc systems, regardless of the working length, did not produce apical microcracks. Copyright © 2017 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  3. Computed tomographic fluoroscopy-guided transthoracic needle biopsy for diagnosis of pulmonary nodules

    International Nuclear Information System (INIS)

    Hirose, Takashi; Mori, Kiyoshi; Machida, Suguru; Tominaga, Keigo; Yokoi, Kohei; Adachi, Mitsuru

    2000-01-01

    The purpose of this study was to evaluate the usefulness of computed tomographic (CT) fluoroscopy-guided transthoracic needle biopsy (TTNB) with an 18-gauge automatic biopsy gun for the diagnosis of pulmonary nodules. Between March 1996 and January 1998, 50 patients in whom pulmonary lesions could not be diagnosed cytopathologically with fiberoptic bronchoscopy or were not clearly visualized with fluoroscopy underwent CT fluoroscopy-guided TTNB. Final pathological diagnoses were 23 lung carcinomas, five pulmonary metastases and 22 benign lesions. Sufficient tissue for analysis was obtained from 48 of the 50 lesions (96%). The overall diagnostic yield of CT fluoroscopy-guided TTNB was 90%. The sensitivity, specificity and accuracy for malignancy were 89%, 100% and 94%, respectively. In 20 of the 22 cases (91%) of benign lesions, histological analysis yielded correct and specific diagnoses. Complications occurred in 22 of the 50 cases (44%). The most common complication was pneumothorax, which occurred in 21 of the 50 cases (42%). Chest tube insertion was required in 6 (12%). Although CT fluoroscopy could not decrease the complication rate, CT fluoroscopy-guided TTNB with an automatic biopsy gun appears to be a promising technique for diagnosing pulmonary lesions, particularly benign lesions. (author)

  4. The computed tomographic appearance of cerebral cysticercosis in adults and children

    International Nuclear Information System (INIS)

    Byrd, S.E.; Locke, G.E.; Biggers, S.; Percy, A.K.

    1982-01-01

    The computed tomographic (CT) scans of 45 patients (30 adults, 15 children) with cerebral cysticercosis were reviewed. These patients had undergone complete diagnostic evaluations including skin tests, laboratory tests, plain skull radiography, radionuclide brain scanning, CT, and cerebral angiography. All of these tests were unrewarding except CT and the indirect hemagglutination tests on the serum. A classification of cerebral cysticercosis based on the location of the lesions in the brain and the CT appearance was developed. Cerebral cysticercosis can be diagnosed by CT findings when there is also a history of seizures and of the patient having lived in an area where the disease is endemic

  5. Development of a portable computed tomographic scanner for on-line imaging of industrial piping systems

    International Nuclear Information System (INIS)

    Jaafar Abdullah; Mohd Arif Hamzah; Mohd Soyapi Mohd Yusof; Mohd Fitri Abdul Rahman; Fadil IsmaiI; Rasif Mohd Zain

    2003-01-01

    Computed tomography (CT) technology is being increasingly developed for industrial application. This paper presents the development of a portable computed tomographic scanner for on?line imaging of industrial piping systems. The theoretical approach, the system hardware, the data acquisition system and the adopted algorithm for image reconstruction are discussed. The scanner has large potential to be used to determine the extent of corrosion under insulation (CUI), to detect blockages, to measure the thickness of deposit/materials built-up on the walls and to improve understanding of material flow in pipelines. (Author)

  6. Clinical significance of computed tomographic arteriography for minute hepatocellular carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Itoh, H; Matsui, O; Suzuki, M; Ida, M; Kitagawa, K [Kanazawa Univ. (Japan). School of Medicine

    1982-03-01

    Computed tomographic arteriography (CTA) can clearly demonstrate minute hepatocellular carcinoma (H.C.C.) more than 2 cm in diameter as an enhanced mass lesion. In this case the precise localization of H.C.C. becomes so obvious that CTA plays an important role to evaluate its resectability. However, H.C.C. of the size from 2 cm to 1 cm indiameter, which is visualized with celiac and infusion hepatic angiography, becomes more difficult in detection, and particularly H.C.C. of less than 1 cm in diameter can hardly be recognized, nor be diagnosed as a malignant nodule by CTA, therefore it appears that in these sizes of H.C.C. the detectability of CTA is not superior to the hepatic angiography.

  7. Linear analysis of rotationally invariant, radially variant tomographic imaging systems

    International Nuclear Information System (INIS)

    Huesmann, R.H.

    1990-01-01

    This paper describes a method to analyze the linear imaging characteristics of rotationally invariant, radially variant tomographic imaging systems using singular value decomposition (SVD). When the projection measurements from such a system are assumed to be samples from independent and identically distributed multi-normal random variables, the best estimate of the emission intensity is given by the unweighted least squares estimator. The noise amplification of this estimator is inversely proportional to the singular values of the normal matrix used to model projection and backprojection. After choosing an acceptable noise amplification, the new method can determine the number of parameters and hence the number of pixels that should be estimated from data acquired from an existing system with a fixed number of angles and projection bins. Conversely, for the design of a new system, the number of angles and projection bins necessary for a given number of pixels and noise amplification can be determined. In general, computing the SVD of the projection normal matrix has cubic computational complexity. However, the projection normal matrix for this class of rotationally invariant, radially variant systems has a block circulant form. A fast parallel algorithm to compute the SVD of this block circulant matrix makes the singular value analysis practical by asymptotically reducing the computation complexity of the method by a multiplicative factor equal to the number of angles squared

  8. Three-dimensional multislice spiral computed tomographic angiography: a potentially useful tool for safer free tissue transfer to complicated regions

    DEFF Research Database (Denmark)

    Demirtas, Yener; Cifci, Mehmet; Kelahmetoglu, Osman

    2009-01-01

    Three-dimensional multislice spiral computed tomographic angiography (3D-MSCTA) is a minimally invasive method of vascular mapping. The aim of this study was to evaluate the clinical usefulness of this imaging technique in delineating the recipient vessels for safer free tissue transfer to compli......Three-dimensional multislice spiral computed tomographic angiography (3D-MSCTA) is a minimally invasive method of vascular mapping. The aim of this study was to evaluate the clinical usefulness of this imaging technique in delineating the recipient vessels for safer free tissue transfer...... be kept in mind, especially inthe patients with peripheral vascular disease. 3D-MSCTA has the potential to replace digital subtraction angiography for planning of microvascular reconstructions and newer devices with higher resolutions will probably increase the reliability of this technique. (c) 2009...

  9. Quantitative analysis of tomographic stress thallium-201 myocardial scintigrams: A multicenter trial

    International Nuclear Information System (INIS)

    Van Train, K.F.; Maddahi, J.; Berman, D.S.; Kiat, H.; Areeda, J.; Prigent, F.; Friedman, J.

    1990-01-01

    The accuracy of the previously developed and validated Cedars-Sinai Medical Center (CSMC) computer program for quantitative analysis of thallium-201 ( 201 TI) stress myocardial tomograms was assessed in a multicenter trial consisting of 242 patients with coronary angiography and 76 with a low likelihood (LL) of coronary artery disease (CAD) involving various cameras, computers, and operators. The program utilized gender-matched normal limits developed from 35 LL patients at CSMC. The multicenter results as compared to those of 168 patients from CSMC were not significantly different with respect to the overall sensitivities (94% versus 95%) and specificities (44% versus 56%) for identification of CAD and normalcy rates which were determined in LL patients (82% for both) and with respect to identification of individual diseased arteries. The results indicate that our method for quantifying tomographic 201 TI stress scintigrams utilizing standard normal limits can be applied at other institutions by different operators, using a variety of cameras and computers, with similar accuracy to that currently obtained at our institution

  10. Development of the two Korean adult tomographic computational phantoms for organ dosimetry

    International Nuclear Information System (INIS)

    Lee, Choonsik; Lee, Choonik; Park, Sang-Hyun; Lee, Jai-Ki

    2006-01-01

    Following the previously developed Korean tomographic phantom, KORMAN, two additional whole-body tomographic phantoms of Korean adult males were developed from magnetic resonance (MR) and computed tomography (CT) images, respectively. Two healthy male volunteers, whose body dimensions were fairly representative of the average Korean adult male, were recruited and scanned for phantom development. Contiguous whole body MR images were obtained from one subject exclusive of the arms, while whole-body CT images were acquired from the second individual. A total of 29 organs and tissues and 19 skeletal sites were segmented via image manipulation techniques such as gray-level thresholding, region growing, and manual drawing, in which each of segmented image slice was subsequently reviewed by an experienced radiologist for anatomical accuracy. The resulting phantoms, the MR-based KTMAN-1 (Korean Typical MAN-1) and the CT-based KTMAN-2 (Korean Typical MAN-2), consist of 300x150x344 voxels with a voxel resolution of 2x2x5 mm 3 for both phantoms. Masses of segmented organs and tissues were calculated as the product of a nominal reference density, the prevoxel volume, and the cumulative number of voxels defining each organs or tissue. These organs masses were then compared with those of both the Asian and the ICRP reference adult male. Organ masses within both KTMAN-1 and KTMAN-2 showed differences within 40% of Asian and ICRP reference values, with the exception of the skin, gall bladder, and pancreas which displayed larger differences. The resulting three-dimensional binary file was ported to the Monte Carlo code MCNPX2.4 to calculate organ doses following external irradiation for illustrative purposes. Colon, lung, liver, and stomach absorbed doses, as well as the effective dose, for idealized photon irradiation geometries (anterior-posterior and right lateral) were determined, and then compared with data from two other tomographic phantoms (Asian and Caucasian), and

  11. Impact of Collateral Status Evaluated by Dynamic Computed Tomographic Angiography on Clinical Outcome in Patients With Ischemic Stroke

    NARCIS (Netherlands)

    van den Wijngaard, Ido R.; Boiten, Jelis; Holswilder, Ghislaine; Algra, Ale; Dippel, Diederik W J; Velthuis, Birgitta K.; Wermer, Marieke J H; van Walderveen, Marianne A A

    2015-01-01

    BACKGROUND AND PURPOSE—: Status of collateral circulation is a strong predictor of outcome after acute ischemic stroke. Our aim was to compare the predictive value of strategies for collateral blood flow assessment with dynamic computed tomographic angiography (CTA) and conventional single-phase CT

  12. The use of tomographic techniques in the mineral processing Industry. A review

    International Nuclear Information System (INIS)

    Witika, L.K.; Jere, E.H.

    2002-01-01

    Process tomographic techniques may be used to analyse the internal state of most of the multiphase process engineering systems such as material segregation in a reactor multiphase flow in pipes and the spatial resolution of mineral grains in multiphase particles. These techniques include radiation computed tomography (X-ray or ray), electrical methods(capacitance, impedance and inductive tomography) positron emission tomography,optical tomography, microwave tomography, acoustic tomographical methods and many more. Many potential applications exist for process tomographic instrumentation for quantitative analysis and fault-detection purposes. Amongst these, electrical methods are widely used for those mineral processes deserving particular attention such as dense-medium separation, hydro cyclones, flotation cells and columns, gas-liquid absorbers, solvent extraction and other liquid-liquid processes, filtration and other solid-liquid processes, grinding mills (both dry and wet, conveyors and hoppers). Development in on-line measurement instrumentation now allow direct observation of the behaviour of fluids inside mineral separation equipment. This offers the possibility to acquire process data to enable models to be devised, to verify theoretical computational fluid dynamics predictions and control of various unit processes. In this review, the most important tomographic sensing methods are reviewed. Examples of the implementation of some electrical methods are illustrated. (authors)

  13. TomoPy: a framework for the analysis of synchrotron tomographic data

    International Nuclear Information System (INIS)

    Gürsoy, Doǧa; De Carlo, Francesco; Xiao, Xianghui; Jacobsen, Chris

    2014-01-01

    A collaborative framework for the analysis of synchrotron tomographic data which has the potential to unify the effort of different facilities and beamlines performing similar tasks is described. The proposed Python-based framework is open-source, platform- and data-format-independent, has multiprocessing capability and supports functional programming that many researchers prefer. Analysis of tomographic datasets at synchrotron light sources (including X-ray transmission tomography, X-ray fluorescence microscopy and X-ray diffraction tomography) is becoming progressively more challenging due to the increasing data acquisition rates that new technologies in X-ray sources and detectors enable. The next generation of synchrotron facilities that are currently under design or construction throughout the world will provide diffraction-limited X-ray sources and are expected to boost the current data rates by several orders of magnitude, stressing the need for the development and integration of efficient analysis tools. Here an attempt to provide a collaborative framework for the analysis of synchrotron tomographic data that has the potential to unify the effort of different facilities and beamlines performing similar tasks is described in detail. The proposed Python-based framework is open-source, platform- and data-format-independent, has multiprocessing capability and supports procedural programming that many researchers prefer. This collaborative platform could affect all major synchrotron facilities where new effort is now dedicated to developing new tools that can be deployed at the facility for real-time processing, as well as distributed to users for off-site data processing

  14. TomoPy: a framework for the analysis of synchrotron tomographic data

    Energy Technology Data Exchange (ETDEWEB)

    Gürsoy, Doǧa, E-mail: dgursoy@aps.anl.gov; De Carlo, Francesco; Xiao, Xianghui; Jacobsen, Chris [Advanced Photon Source, Argonne National Laboratory, 9700 South Cass Avenue, Argonne, IL 60439-4837 (United States)

    2014-08-01

    A collaborative framework for the analysis of synchrotron tomographic data which has the potential to unify the effort of different facilities and beamlines performing similar tasks is described. The proposed Python-based framework is open-source, platform- and data-format-independent, has multiprocessing capability and supports functional programming that many researchers prefer. Analysis of tomographic datasets at synchrotron light sources (including X-ray transmission tomography, X-ray fluorescence microscopy and X-ray diffraction tomography) is becoming progressively more challenging due to the increasing data acquisition rates that new technologies in X-ray sources and detectors enable. The next generation of synchrotron facilities that are currently under design or construction throughout the world will provide diffraction-limited X-ray sources and are expected to boost the current data rates by several orders of magnitude, stressing the need for the development and integration of efficient analysis tools. Here an attempt to provide a collaborative framework for the analysis of synchrotron tomographic data that has the potential to unify the effort of different facilities and beamlines performing similar tasks is described in detail. The proposed Python-based framework is open-source, platform- and data-format-independent, has multiprocessing capability and supports procedural programming that many researchers prefer. This collaborative platform could affect all major synchrotron facilities where new effort is now dedicated to developing new tools that can be deployed at the facility for real-time processing, as well as distributed to users for off-site data processing.

  15. Tomographic PIV: principles and practice

    International Nuclear Information System (INIS)

    Scarano, F

    2013-01-01

    A survey is given of the major developments in three-dimensional velocity field measurements using the tomographic particle image velocimetry (PIV) technique. The appearance of tomo-PIV dates back seven years from the present review (Elsinga et al 2005a 6th Int. Symp. PIV (Pasadena, CA)) and this approach has rapidly spread as a versatile, robust and accurate technique to investigate three-dimensional flows (Arroyo and Hinsch 2008 Topics in Applied Physics vol 112 ed A Schröder and C E Willert (Berlin: Springer) pp 127–54) and turbulence physics in particular. A considerable number of applications have been achieved over a wide range of flow problems, which requires the current status and capabilities of tomographic PIV to be reviewed. The fundamental aspects of the technique are discussed beginning from hardware considerations for volume illumination, imaging systems, their configurations and system calibration. The data processing aspects are of uppermost importance: image pre-processing, 3D object reconstruction and particle motion analysis are presented with their fundamental aspects along with the most advanced approaches. Reconstruction and cross-correlation algorithms, attaining higher measurement precision, spatial resolution or higher computational efficiency, are also discussed. The exploitation of 3D and time-resolved (4D) tomographic PIV data includes the evaluation of flow field pressure on the basis of the flow governing equation. The discussion also covers a-posteriori error analysis techniques. The most relevant applications of tomo-PIV in fluid mechanics are surveyed, covering experiments in air and water flows. In measurements in flow regimes from low-speed to supersonic, most emphasis is given to the complex 3D organization of turbulent coherent structures. (topical review)

  16. Cone Beam Computed Tomographic imaging in orthodontics.

    Science.gov (United States)

    Scarfe, W C; Azevedo, B; Toghyani, S; Farman, A G

    2017-03-01

    Over the last 15 years, cone beam computed tomographic (CBCT) imaging has emerged as an important supplemental radiographic technique for orthodontic diagnosis and treatment planning, especially in situations which require an understanding of the complex anatomic relationships and surrounding structures of the maxillofacial skeleton. CBCT imaging provides unique features and advantages to enhance orthodontic practice over conventional extraoral radiographic imaging. While it is the responsibility of each practitioner to make a decision, in tandem with the patient/family, consensus-derived, evidence-based clinical guidelines are available to assist the clinician in the decision-making process. Specific recommendations provide selection guidance based on variables such as phase of treatment, clinically-assessed treatment difficulty, the presence of dental and/or skeletal modifying conditions, and pathology. CBCT imaging in orthodontics should always be considered wisely as children have conservatively, on average, a three to five times greater radiation risk compared with adults for the same exposure. The purpose of this paper is to provide an understanding of the operation of CBCT equipment as it relates to image quality and dose, highlight the benefits of the technique in orthodontic practice, and provide guidance on appropriate clinical use with respect to radiation dose and relative risk, particularly for the paediatric patient. © 2017 Australian Dental Association.

  17. Tomographs based on non-conventional radiation sources and methods

    International Nuclear Information System (INIS)

    Barbuzza, R.; Fresno, M. del; Venere, Marcelo J.; Clausse, Alejandro; Moreno, C.

    2000-01-01

    Computer techniques for tomographic reconstruction of objects X-rayed with a compact plasma focus (PF) are presented. The implemented reconstruction algorithms are based on stochastic searching of solutions of Radon equation, using Genetic Algorithms and Monte Carlo methods. Numerical experiments using actual projections were performed concluding the feasibility of the application of both methods in tomographic reconstruction problem. (author)

  18. Computed tomographic colonography (CTC); colorectal cancer diagnosis with CTC in an Auckland population

    International Nuclear Information System (INIS)

    Moore, Helen; Dodd, Nicholas

    2013-01-01

    To determine the sensitivity of computed tomographic colonography (CTC) in the detection of colorectal cancer in our population and evaluate the reasons why these lesions may be missed on CTC. All patients who underwent CTC in the 65-month period from 1 January 2004 to 1 July 2009 were included in the analysis. Demographic data and CTC findings were recorded, according to the CT Colonography Reporting and Data System. Data were cross-matched with the National Cancer Registry results for colorectal cancer cases between 1 January 2004 and 1 October 2009, 3 months longer to include any delayed diagnoses. There were 2026 consecutive CTC patients, comprising 52.6% female, average age of 60 years; range 19–87. Approximately 84% were symptomatic. There were 45 confirmed colorectal cancers among this patient group in the National Cancer Registry during the relevant time period compared with 43 suspected cancers on CTC, giving a miss rate of 2 of 45, or 4.4%. The sensitivity of 95% for CTC in the detection of colorectal cancer compares favourably with the published national and international data.

  19. Measurement of facial soft tissues thickness using 3D computed tomographic images

    Energy Technology Data Exchange (ETDEWEB)

    Jeong, Ho Gul; Kim, Kee Deog; Shin, Dong Won; Hu, Kyung Seok; Lee, Jae Bum; Park, Hyok; Park, Chang Seo [Yonsei Univ. Hospital, Seoul (Korea, Republic of); Han, Seung Ho [Catholic Univ. of Korea, Seoul (Korea, Republic of)

    2006-03-15

    To evaluate accuracy and reliability of program to measure facial soft tissue thickness using 3D computed tomographic images by comparing with direct measurement. One cadaver was scanned with a Helical CT with 3 mm slice thickness and 3 mm/sec table speed. The acquired data was reconstructed with 1.5 mm reconstruction interval and the images were transferred to a personal computer. The facial soft tissue thickness were measured using a program developed newly in 3D image. For direct measurement, the cadaver was cut with a bone cutter and then a ruler was placed above the cut side. The procedure was followed by taking pictures of the facial soft tissues with a high-resolution digital camera. Then the measurements were done in the photographic images and repeated for ten times. A repeated measure analysis of variance was adopted to compare and analyze the measurements resulting from the two different methods. Comparison according to the areas was analyzed by Mann-Whitney test. There were no statistically significant differences between the direct measurements and those using the 3D images(p>0.05). There were statistical differences in the measurements on 17 points but all the points except 2 points showed a mean difference of 0.5 mm or less. The developed software program to measure the facial soft tissue thickness using 3D images was so accurate that it allows to measure facial soft tissue thickness more easily in forensic science and anthropology.

  20. Measurement of facial soft tissues thickness using 3D computed tomographic images

    International Nuclear Information System (INIS)

    Jeong, Ho Gul; Kim, Kee Deog; Shin, Dong Won; Hu, Kyung Seok; Lee, Jae Bum; Park, Hyok; Park, Chang Seo; Han, Seung Ho

    2006-01-01

    To evaluate accuracy and reliability of program to measure facial soft tissue thickness using 3D computed tomographic images by comparing with direct measurement. One cadaver was scanned with a Helical CT with 3 mm slice thickness and 3 mm/sec table speed. The acquired data was reconstructed with 1.5 mm reconstruction interval and the images were transferred to a personal computer. The facial soft tissue thickness were measured using a program developed newly in 3D image. For direct measurement, the cadaver was cut with a bone cutter and then a ruler was placed above the cut side. The procedure was followed by taking pictures of the facial soft tissues with a high-resolution digital camera. Then the measurements were done in the photographic images and repeated for ten times. A repeated measure analysis of variance was adopted to compare and analyze the measurements resulting from the two different methods. Comparison according to the areas was analyzed by Mann-Whitney test. There were no statistically significant differences between the direct measurements and those using the 3D images(p>0.05). There were statistical differences in the measurements on 17 points but all the points except 2 points showed a mean difference of 0.5 mm or less. The developed software program to measure the facial soft tissue thickness using 3D images was so accurate that it allows to measure facial soft tissue thickness more easily in forensic science and anthropology

  1. Computed Tomographic Findings and Mortality in Patients With Pneumomediastinum From Blunt Trauma.

    Science.gov (United States)

    Lee, Wayne S; Chong, Vincent E; Victorino, Gregory P

    2015-08-01

    The care of most patients with pneumomediastinum (PNM) due to trauma can be managed conservatively; however, owing to aerodigestive tract injury and other associated injuries, there is a subset of patients with PNM who are at higher risk of mortality but can be difficult to identify. To characterize computed tomographic (CT) findings associated with mortality in patients with PNM due to blunt trauma. A retrospective review of medical records from January 1, 2002, to December 31, 2011, was conducted at a university-based urban trauma center. The patients evaluated were those injured by blunt trauma and found to have PNM on initial chest CT scanning. Data analysis was performed July 2, 2013, to June 18, 2014. In-hospital mortality. During the study period, 3327 patients with blunt trauma underwent chest CT. Of these, 72 patients (2.2%) had PNM. Patients with PNM had higher Injury Severity Scores (P blunt trauma; however, CT findings of posterior PNM, air in all mediastinal compartments, and concurrent hemothorax are associated with increased mortality. These CT findings could be used as a triage tool to alert the trauma surgeon to a potentially lethal injury.

  2. Double Colorectal Cancer Only Diagnosed by Computed Tomographic Colonography

    Directory of Open Access Journals (Sweden)

    Koichi Nagata

    2008-02-01

    Full Text Available A 58-year-old woman presented to her physician with rectal bleeding and intermittent diarrhea. Optical colonoscopy revealed a bulky tumor which was diagnosed as rectal cancer. She was referred to our institution for further evaluation and treatment. Slim optical colonoscopy showed an obstructive cancer in the rectosigmoid junction and no information of the proximal side of the obstruction. The patient then underwent computed tomographic (CT colonography for further evaluation of the proximal side. Three-dimensional endoluminal ‘fly-through’ images revealed another protruded lesion in the proximal side of the obstruction. Diagnosis of synchronous double cancer was made by CT colonography. This CT data was not only used to create three-dimensional images but also to decide on a preoperative clinical staging. Laparoscopy-assisted high anterior resection was performed and T3 rectal cancer and T1 sigmoid colon cancer were confirmed in the resected specimen. Follow-up optical colonoscopy revealed no other tumors. CT colonography has recently become a popular preoperative examination tool with significant improvement in quality of image due to a rapid progress in computer technology. CT colonography correctly showed synchronous double cancer in our case and provided crucial information for planning surgery. We recommend that CT colonography should be used for evaluating the proximal side of obstructive colorectal cancer.

  3. Reconstruction of computed tomographic image from a few x-ray projections by means of accelerative gradient method

    International Nuclear Information System (INIS)

    Kobayashi, Fujio; Yamaguchi, Shoichiro

    1982-01-01

    A method of the reconstruction of computed tomographic images was proposed to reduce the exposure dose to X-ray. The method is the small number of X-ray projection method by accelerative gradient method. The procedures of computation are described. The algorithm of these procedures is simple, the convergence of the computation is fast, and the required memory capacity is small. Numerical simulation was carried out to conform the validity of this method. A sample of simple shape was considered, projection data were given, and the images were reconstructed from 6 views. Good results were obtained, and the method is considered to be useful. (Kato, T.)

  4. Computed tomographic study of 50 patients with hypodense hepatic injuries in childhood; Estudo de 50 casos por tomografia computadorizada de lesoes hipodensas hepaticas fundamentais na infancia

    Energy Technology Data Exchange (ETDEWEB)

    Pereira, Ines Minniti Rodrigues; Alvares, Beatriz Regina; Baracat, Jamal; Martins, Daniel Lahan [Universidade Estadual de Campinas, SP (Brazil). Faculdade de Ciencias Medicas. Dept. de Radiologia]. E-mail: iminniti@fcm.unicamp.br; Pereira, Ricardo Minniti Rodrigues [Universidade Estadual de Campinas, SP (Brazil). Faculdade de Ciencias Medicas

    2006-03-15

    Objective: To describe the different tomographic findings in hypodense hepatic lesions in children and its differential diagnosis. Materials and methods: computed tomographic studies were obtained from 50 patients (age range: 0-16 years) with low-density liver lesions previously diagnosed by ultrasound. Images were made before and after administration of intravenous contrast medium. Image findings were analyzed and afterwards correlated with anatomopathological diagnosis. Results: forty-seven of 50 cases were confirmed, 30 by anatomopathological diagnosis. Most of then were benign lesions, hemangioma in 20%. Such lesions presented a homogeneous contrast absorption, mainly at the delayed phase, differing from malignant lesions. Metastasis was the most frequently found malignant lesion (18%). Conclusion: computed tomographic study is of great value in complementing the diagnosis of hypodense hepatic lesions in children, and must follow ultrasound diagnosis as a routine procedure. (author)

  5. Pipelining Computational Stages of the Tomographic Reconstructor for Multi-Object Adaptive Optics on a Multi-GPU System

    KAUST Repository

    Charara, Ali

    2014-11-01

    The European Extremely Large Telescope project (E-ELT) is one of Europe\\'s highest priorities in ground-based astronomy. ELTs are built on top of a variety of highly sensitive and critical astronomical instruments. In particular, a new instrument called MOSAIC has been proposed to perform multi-object spectroscopy using the Multi-Object Adaptive Optics (MOAO) technique. The core implementation of the simulation lies in the intensive computation of a tomographic reconstruct or (TR), which is used to drive the deformable mirror in real time from the measurements. A new numerical algorithm is proposed (1) to capture the actual experimental noise and (2) to substantially speed up previous implementations by exposing more concurrency, while reducing the number of floating-point operations. Based on the Matrices Over Runtime System at Exascale numerical library (MORSE), a dynamic scheduler drives all computational stages of the tomographic reconstruct or simulation and allows to pipeline and to run tasks out-of order across different stages on heterogeneous systems, while ensuring data coherency and dependencies. The proposed TR simulation outperforms asymptotically previous state-of-the-art implementations up to 13-fold speedup. At more than 50000 unknowns, this appears to be the largest-scale AO problem submitted to computation, to date, and opens new research directions for extreme scale AO simulations. © 2014 IEEE.

  6. Brain computed tomographic findings in post-cardiopulmonary resuscitation patients

    International Nuclear Information System (INIS)

    Ishida, Tsuguharu; Yoshinaga, Kazumasa; Horibe, Takashi; Kokubu, Kiyokazu; Kokura, Yoshihiro; Matsui, Konosuke; Inamoto, Kazuo.

    1986-01-01

    We retrospectively assessed the brain computed tomographic (CT) findings in 22 post-cardiopulmonary resuscitation (CPR) patients excluding neonatal cases. On the basis of the CT findings, the patients were divided into two groups. Eight patients (36.4 %) had bilateral abnormal lowdensity areas in the basal ganglia (Group I). The remaining 14 patients (63.6 %) had no abnormalities in that area (Group II). In Group I, the incidence of primary cardiac arrest and duration of advanced life support (ALS) was significantly different (p < 0.05) from Group II. Sex, age, duration of basic life support (BLS), time elapsed from initiation of BLS to initial CT and from initiation of ALS to initial CT was not significantly different between the two groups. Outcome was very poor in both groups and no significant difference was noted between them. We conclude that primary cardiac arrest and long duration of ALS were predictors of abnormal bilateral low-density areas in the basal ganglia in post-CPR patients. However, their appearance was not related to outcome. (author)

  7. Noncontrast computed tomographic Hounsfield unit evaluation of cerebral venous thrombosis: a quantitative evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Besachio, David A. [University of Utah, Department of Radiology, Salt Lake City (United States); United States Navy, Bethesda, MD (United States); Quigley, Edward P.; Shah, Lubdha M.; Salzman, Karen L. [University of Utah, Department of Radiology, Salt Lake City (United States)

    2013-08-15

    Our objective is to determine the utility of noncontrast Hounsfield unit values, Hounsfield unit values corrected for the patient's hematocrit, and venoarterial Hounsfield unit difference measurements in the identification of intracranial venous thrombosis on noncontrast head computed tomography. We retrospectively reviewed noncontrast head computed tomography exams performed in both normal patients and those with cerebral venous thrombosis, acquiring Hounsfield unit values in normal and thrombosed cerebral venous structures. Also, we acquired Hounsfield unit values in the internal carotid artery for comparison to thrombosed and nonthrombosed venous structures and compared the venous Hounsfield unit values to the patient's hematocrit. A significant difference is identified between Hounsfield unit values in thrombosed and nonthrombosed venous structures. Applying Hounsfield unit threshold values of greater than 65, a Hounsfield unit to hematocrit ratio of greater than 1.7, and venoarterial difference values greater than 15 alone and in combination, the majority of cases of venous thrombosis are identifiable on noncontrast head computed tomography. Absolute Hounsfield unit values, Hounsfield unit to hematocrit ratios, and venoarterial Hounsfield unit value differences are a useful adjunct in noncontrast head computed tomographic evaluation of cerebral venous thrombosis. (orig.)

  8. Noncontrast computed tomographic Hounsfield unit evaluation of cerebral venous thrombosis: a quantitative evaluation

    International Nuclear Information System (INIS)

    Besachio, David A.; Quigley, Edward P.; Shah, Lubdha M.; Salzman, Karen L.

    2013-01-01

    Our objective is to determine the utility of noncontrast Hounsfield unit values, Hounsfield unit values corrected for the patient's hematocrit, and venoarterial Hounsfield unit difference measurements in the identification of intracranial venous thrombosis on noncontrast head computed tomography. We retrospectively reviewed noncontrast head computed tomography exams performed in both normal patients and those with cerebral venous thrombosis, acquiring Hounsfield unit values in normal and thrombosed cerebral venous structures. Also, we acquired Hounsfield unit values in the internal carotid artery for comparison to thrombosed and nonthrombosed venous structures and compared the venous Hounsfield unit values to the patient's hematocrit. A significant difference is identified between Hounsfield unit values in thrombosed and nonthrombosed venous structures. Applying Hounsfield unit threshold values of greater than 65, a Hounsfield unit to hematocrit ratio of greater than 1.7, and venoarterial difference values greater than 15 alone and in combination, the majority of cases of venous thrombosis are identifiable on noncontrast head computed tomography. Absolute Hounsfield unit values, Hounsfield unit to hematocrit ratios, and venoarterial Hounsfield unit value differences are a useful adjunct in noncontrast head computed tomographic evaluation of cerebral venous thrombosis. (orig.)

  9. Computed tomographic and cross-sectional anatomy of the normal pacu (Colossoma macroponum).

    Science.gov (United States)

    Carr, Alaina; Weber, E P Scott; Murphy, Chris J; Zwingenberger, Alison

    2014-03-01

    The purpose of this study was to compare and define the normal cross-sectional gross and computed tomographic (CT) anatomy for a species of boney fish to better gain insight into the use of advanced diagnostic imaging for future clinical cases. The pacu (Colossoma macropomum) was used because of its widespread presence in the aquarium trade, its relatively large body size, and its importance in the research and aquaculture settings. Transverse 0.6-mm CT images of three cadaver fish were obtained and compared to corresponding frozen cross sections of the fish. Relevant anatomic structures were identified and labeled at each level; the Hounsfield unit density of major organs was established. The images presented good anatomic detail and provide a reference for future research and clinical investigation.

  10. Computed tomographic findings of hepatocellular carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Eun, Chung Kie [Kyung Hee University College of Medicine, Seoul (Korea, Republic of)

    1982-09-15

    It is well known that CT is very useful in the evaluation of hepatocellular carcinoma. The computed tomographic findings of 56 patients diagnosed as hepatocellular carcinoma were reviewed and analyzed. The results were as follows: 1. The male to female ratio was 3 : 1 and the age ranged from 31 to 73 years with average age of 54 years. 2. Alpha-fetoprotein was positive in 19 out of 38 cases (50%). HBsAg was positive in 8 out of 33 cases (24%). 3. All lesions were seen as areas of low density except 1 case (0%) of isodensity, and 40 cases (72%) appeared to be solitary while 15 (26%) were multifocal. The low density was homogenous in 13 cases (24%) and inhomogenous in 42 cases (76%), and 18 cases out of 42 cases inhomogenous low density showed peripheal and/or central nodular enhancement. The additional findings were contour changes in 37 cases (66%), metastasis in 35 cases (63%), splenomegaly in 23 cases (42%) and ascities in 22 cases (39%). 4. In postcontrast scans, 41 cases (80%) out of 51 cases showed the change of density after contrast infusion. The presence and extent of tumors were better seen after contrast infusion in 30 cases (59%), better seen before contrast infusion in 11 cases (21%) and no significant difference before and after contrast infusion in 10 cases (20%). 5. The sites of involved lobe were right lobe in 38 cases (68%), left lobe in 5 cases (9%) and both lobes in 13 cases (23%). 6. 35 cases (63%) showed evidence of metastasis to regional lymph nodes, organ or tissues.

  11. Computed tomographic findings of cerebral paragonimiasis

    International Nuclear Information System (INIS)

    Bae, Weon Tae; Jung, Min Ki; Kang, Heoung Keun; Chung, Hyon De

    1988-01-01

    Authors analyzed the computed tomographic (CT) findings of 19 cases pathologically and clinically proven cerebral paragonimiasis that were performed at Chonnam University Hospital from April 1983 through March 1987. The results were as follows: 1. Male to female ratio was 15:4 and the most prevalent age group was 3rd decade (7 cases). The common symptoms were epileptic seizure (16 cases) and headache (12 cases). 2. The multiplicity of cerebral paragonimiasis was 7 of 19 cases and the distributions of lesion were occipital (11 cases), temporal (6 cases), frontal (5 cases) and parietal (5 cases) lobe. 3. The calcification on CT scan were single (7 cases) or multiple (7 cases) and the shape of calcification were nodular (10 cases), soap babble of ring (8 cases), and stippled (6 cases). The pattern of contrast enhancement were ring (5 cases) or nodular (1 case), and along the basal cistern (1 case with arachnoiditis). 4. 12 out of 13 cases, had long clinical symptoms over 3 years with calcifications, could be analyzed according to Valentine's vascular territory; 6 cases in PCA territory, 3 in MCA and 3 in ACA. 5. CT findings were noted according to the duration of symptoms; 5 cases, had symptoms less than 1 year, showed abscess (5 cases) and arachnoiditis (1 case) with brain edema, mass effect, hydrocephalus and contrast enhancement but no calcification in all. One case, had symptom of 1 year and 2 months, showed partially calcified granulomatous lesion with perifocal edema and contrast enhancement, 13 cases, had symptoms over 3 years, showed multiple calcification with brain atrophy (10 cases), but no contrast enhancement in all cases.

  12. Computed tomographic findings of liver injury in adults

    International Nuclear Information System (INIS)

    Ha, Deok Gi; Lee, Hyeon Kyeong; Lee, Won Jae; Oh, Yeon Hee; Lee, Sung Hee; Yun, Jee Yeong; Lee, Tae Woo; Lee, Sung Woo; Park, Soo Soung

    1994-01-01

    We studied to compare computed tomographic(CT) findings of liver injury with management method in adults and, moreover, to present the CT basis for the management. We retrospectively reviewed CT scans of 43 adults diagnosed as liver injury during a 66 month period. Thirty-eight patients were hemodynamically stable. Thirty-two of them were managed conservatively, whereas six managed operatively. Five unstable patients underwent emergency operation. We classified CT findings according to the severity of liver injuries(ie, hematoma, laceration, and periportal tracking) and hemoperitoneum, ranging from grade 1 to 5 and from 0 to 3 +. respectively. Thus, we compared the CT classifications with their management(ie, operation rate), especially hemodynamically stable patients. Operation rates of all patients and hemodynamically stable patients were 26% and 16%, respectively. Operation rate at each grade of liver injury was low, especially in hemodynamically stable, despite relatively high operation rate in grade 4. Operation rate of 3+ homoperitoneum was 100%, including hemodynamically stable patients, in contrast to otherwise low operation rate of others. Most liver injury in adults, including grade 4, were managed conservatively, especially hemodynamically stable. Though large amount of hemoperitoneum(ie, 3+) required operation, most hemooperitoeum were managed conservatively. Thus, CT findings of liver injury is helpful in the decision for the management method

  13. Computed tomographic mammography using a conventional body scanner.

    Science.gov (United States)

    Chang, C H; Nesbit, D E; Fisher, D R; Fritz, S L; Dwyer, S J; Templeton, A W; Lin, F; Jewell, W R

    1982-03-01

    The technique for computed tomographic (CT) examination of the breasts using a conventional body scanner is described, and experience with 67 patients is reported. In the diagnosis of both malignant and benign breast lesions, the results with a body scanner were equal to those of a dedicated CT/M mammographic unit. Although the CT study of the breast cannot replace conventional mammography in screening or in routine diagnostic workup, the unique capability of demonstrating both anatomic changes and increased iodide concentration in a cancer provides many advantages over conventional mammography. CT mammography appears to have the capability to detect breast cancers that are occult to other methods. Indications for a CT study of the breasts are: (1) clinically suspected breast cancer, especially with a mammographically occult lesion; (2) questionable mammographic findings, including microcalcifications, tumor shape, architectural distortion, and uncertain lesion location; and (3) evaluation of postbiopsy or postlumpectomy breast cancers when a primary irradiation therapy is contemplated. Breast CT also appears to be a valuable diagnostic tool in searching for a second primary breast cancer, follow-up study of postirradiation of breast cancer, followup study for postmastectomy patients, and screening procedure for genetically high-risk patients, especially those with dense breasts.

  14. Computed tomographic criteria for differential diagnosis between exacerbation of focal chronic pancreatitis and carcinoma located in the head of the pancreas

    International Nuclear Information System (INIS)

    Ivanov, A.; Tonchev, Z.

    1995-01-01

    A group of 126 patients with CT-finding of tumor mass in the head of the pancreas is studied. Signs of acute exacerbation of focal chronic pancreatitis are found in 28 of them. Carcinoma of the head of pancreas is diagnosed in 98 patients. Surgical and histological verification is performed in 84 (86%) patients with carcinoma of the pancreas. In 77 (92%) cases the computed tomographic diagnosis coincides with the histological one, while in the remaining 7 (8%) it fails to coincide. The morphological and densitometric changes were analyzed with respect to their frequency. On account of the nonspecific character of the computed tomographic signs a symptom constellation is developed which facilitates the differential diagnosis of the acute exacerbation of focal pancreatitis and the carcinoma. The changes in density of lesions observed after application of contrast media were found to be of significant value. 16 refs., 6 figs. (author)

  15. Computer tomographic detection of an intraspinal arachnoidal cyst

    Energy Technology Data Exchange (ETDEWEB)

    Kuckein, D; Walter, K; Paal, G

    1981-03-01

    A 46 year old female patient who after 3-4 weeks of influenza suffered from strong headaches, vomiting and rotatory vertigo was subjected to a myelograph and then to a computerized tomographic investigation due to suspect cerebrospinal fluid. The computerized tomography is better than the myelography in diagnosing intraspinal arachnoidal cysts, however this should be preceded by most accurate possible segment location.

  16. COMPUTED TOMOGRAPHIC EVALUATION OF POSTERIOR REVERSIBLE ENCEPHALOPATHY SYNDROME

    Directory of Open Access Journals (Sweden)

    Vishwaprem Raj

    2016-04-01

    Full Text Available BACKGROUND AND PURPOSE Posterior Reversible Encephalopathy Syndrome (PRES is a neurotoxic state that occurs secondary to the inability of posterior circulation to autoregulate. The clinical spectrum and the underlying pathophysiology are still poorly defined. No conclusive evidence has been put forward regarding the relationship between clinical conditions and specific imaging findings of severity or location of oedema. PURPOSE To assess the role of computed tomography in evaluation of Posterior Reversible Encephalopathy Syndrome. MATERIALS AND METHODS 55 patients referred to the Department of Radio-Diagnosis, with a history of neurological abnormalities, including altered mental function, visual loss, stupor with a predisposing history favouring PRES and followed up for a period of 10 – 30 days. RESULTS 21 patients (38.2% were females. 32 patients (58.1% were in the age group between 21 to 30 years. Predisposing condition; 16 (29.1% presented with pre-eclampsia, 12 (21.8% with post-partum status in altered sensorium, 9 (16.4% with seizures, 7 (12.7% with hypertension, 6 (10.9% with visual disturbances, 4 (7.3% with eclampsia and 1 (1.8% with uraemia. 20 cases (36.4% showed findings suggestive of posterior reversible encephalopathy syndrome on initial computed tomography examination. 35 cases showed no initial radiological evidence suggestive of posterior reversible encephalopathy syndrome. Of the 20 cases which showed computed tomographic evidence of posterior reversible encephalopathy syndrome, recovery was noted in 5 cases (9.1%. Persistence of findings detected on first CT was noted in 13 patients (23.6%. Regional predominance of the lesions was as follows. Frontal lobe (39%, Parietal lobe (32%, Temporal lobe (15% and occipital lobe (15%. CONCLUSION Varied clinical manifestations are associated with anatomical findings recognisable by neuro-imaging as PRES. Prompt imaging is necessary for the recognition of the condition and appropriate

  17. Computed tomographic appearance of mucormycosis

    International Nuclear Information System (INIS)

    Vogl, T.J.; Hinrichs, T.; Jacobi, V.; Boehme, A.; Hoelzer, D.

    2000-01-01

    Aim: Analysis of the morphological characteristics of pulmonary mucormycosis using computed tomography (CT). Material and methods: Prospective analysis of CT studies in 9 patients out of 19 patients with proven pulmonary mucormycosis. Results: Pulmonary mucormycosis was most frequently found in the upper lobe bilaterally (51% of all nodules). In 22% of the manifestations, the morphological criterion of a 'bird's nest' could be verified in CT, in 37% central necrotic areas were detected. In 37% an open bronchus was diagnosed, in 6% we observed bronchiectases. 43% of all nodules presented with a halo sign. In three patients we found pleural effusions, enlarged mediastinal lymph nodes were diagnosed in one patient. Conclusion: Computed tomography allows an improved diagnosis and therapeutic follow-up in patients suffering from pulmonary mucormycosis. (orig.) [de

  18. Expediting model-based optoacoustic reconstructions with tomographic symmetries

    International Nuclear Information System (INIS)

    Lutzweiler, Christian; Deán-Ben, Xosé Luís; Razansky, Daniel

    2014-01-01

    Purpose: Image quantification in optoacoustic tomography implies the use of accurate forward models of excitation, propagation, and detection of optoacoustic signals while inversions with high spatial resolution usually involve very large matrices, leading to unreasonably long computation times. The development of fast and memory efficient model-based approaches represents then an important challenge to advance on the quantitative and dynamic imaging capabilities of tomographic optoacoustic imaging. Methods: Herein, a method for simplification and acceleration of model-based inversions, relying on inherent symmetries present in common tomographic acquisition geometries, has been introduced. The method is showcased for the case of cylindrical symmetries by using polar image discretization of the time-domain optoacoustic forward model combined with efficient storage and inversion strategies. Results: The suggested methodology is shown to render fast and accurate model-based inversions in both numerical simulations andpost mortem small animal experiments. In case of a full-view detection scheme, the memory requirements are reduced by one order of magnitude while high-resolution reconstructions are achieved at video rate. Conclusions: By considering the rotational symmetry present in many tomographic optoacoustic imaging systems, the proposed methodology allows exploiting the advantages of model-based algorithms with feasible computational requirements and fast reconstruction times, so that its convenience and general applicability in optoacoustic imaging systems with tomographic symmetries is anticipated

  19. Correlation between presumed sinusitis-induced pain and paranasal sinus computed tomographic findings.

    Science.gov (United States)

    Mudgil, Shikha P; Wise, Scott W; Hopper, Kenneth D; Kasales, Claudia J; Mauger, David; Fornadley, John A

    2002-02-01

    The correlation between facial and/or head pain in patients clinically suspected of having sinusitis and actual localized findings on sinus computed tomographic (CT) imaging are poorly understood. To prospectively evaluate the relationship of paranasal sinus pain symptoms with CT imaging. Two hundred consecutive patients referred by otolaryngologists and internists for CT of the paranasal sinuses participated by completing a questionnaire immediately before undergoing CT. Three radiologists blinded to the patients' responses scored the degree of air/fluid level, mucosal thickening, bony reaction, and mucus retention cysts using a graded scale of severity (0 to 3 points). The osteomeatal complexes and nasolacrimal ducts were also evaluated for patency. Bivariate analysis was performed to evaluate the relationship between patients' localized symptoms and CT findings in the respective sinus. One hundred sixty-three patients (82%) reported having some form of facial pain or headache. The right temple/forehead was the most frequently reported region of maximal pain. On CT imaging the maxillary sinus was the most frequently involved sinus. Bivariate analysis failed to show any relationship between patient symptoms and findings on CT. Patients with a normal CT reported a mean 5.88 sites of facial or head pain versus 5.45 sites for patients with an abnormal CT. Patient-based responses of sinonasal pain symptoms fail to correlate with findings in the respective sinuses. CT should therefore be reserved for delineating the anatomy and degree of sinus disease before surgical intervention.

  20. Performance of analytical methods for tomographic gamma scanning

    International Nuclear Information System (INIS)

    Prettyman, T.H.; Mercer, D.J.

    1997-01-01

    The use of gamma-ray computerized tomography for nondestructive assay of radioactive materials has led to the development of specialized analytical methods. Over the past few years, Los Alamos has developed and implemented a computer code, called ARC-TGS, for the analysis of data obtained by tomographic gamma scanning (TGS). ARC-TGS reduces TGS transmission and emission tomographic data, providing the user with images of the sample contents, the activity or mass of selected radionuclides, and an estimate of the uncertainty in the measured quantities. The results provided by ARC-TGS can be corrected for self-attenuation when the isotope of interest emits more than one gamma-ray. In addition, ARC-TGS provides information needed to estimate TGS quantification limits and to estimate the scan time needed to screen for small amounts of radioactivity. In this report, an overview of the analytical methods used by ARC-TGS is presented along with an assessment of the performance of these methods for TGS

  1. The great imitator: IgG4 periaortitis masquerading as an acute aortic syndrome on computed tomographic angiography

    OpenAIRE

    Moore, Drew W.; Hansen, Neil J.; DiMaio, Dominick J.; Harrison, William L.

    2016-01-01

    We present the case of a 52-year-old woman who presented to the emergency department with chest and neck pain. Initial cervical spine magnetic resonance imaging shows an abnormal flow void in the left vertebral artery, which prompted a computed tomographic angiogram. This demonstrated a hyperdense thickened ascending aortic wall, which extended into the great vessel origins. Clinically and radiographically interpreted as an acute aortic syndrome and/or intramural hematoma, the patient underwe...

  2. Computer tomographic detection of an intraspinal arachnoidal cyst

    International Nuclear Information System (INIS)

    Kuckein, D.; Walter, K.; Paal, G.; Staedtisches Krankenhaus Harlaching, Muenchen

    1981-01-01

    A 46 year old female patient who after 3-4 weeks of influenza suffered from strong headaches, vomiting and rotatory vertigo was subjected to a myelograph and then to a computerized tomographic investigation due to suspect cerebrospinal fluid. The computerized tomography is better than the myelography in diagnosing intraspinal arachnoidal cysts, however this should be preceded by most accurate possible segment location. (MG) [de

  3. Methodological study of radionuclide tomographic phase analysis in localization of accessory conduction pathway in patients with wolff-parkinson-white syndrome

    International Nuclear Information System (INIS)

    Wo Jinshan; Zhu Junren; Li Zhishan

    1994-01-01

    In this study, the methodology of tomographic phase analysis to detect the site of accessory conduction pathway (ACP) in patients with Wolff-Parkinson-White syndrome was presented. We analyzed the major factors that affect image reconstruction, selection of tomographic planes and phase analysis, also discussed the key step for reconstruction short-axial section that parallel and closest to the level of atrio-ventricular rings. Of five patients undergoing this procedure prior to surgery, tomographic phase analysis correctly identified the site of ACP confirmed by epicardial mapping in all of the five patients. Our results suggest this approach to be an objective, clear and correct one for localizing ACP

  4. Automating the segmentation of medical images for the production of voxel tomographic computational models

    International Nuclear Information System (INIS)

    Caon, M.

    2001-01-01

    Radiation dosimetry for the diagnostic medical imaging procedures performed on humans requires anatomically accurate, computational models. These may be constructed from medical images as voxel-based tomographic models. However, they are time consuming to produce and as a consequence, there are few available. This paper discusses the emergence of semi-automatic segmentation techniques and describes an application (iRAD) written in Microsoft Visual Basic that allows the bitmap of a medical image to be segmented interactively and semi-automatically while displayed in Microsoft Excel. iRAD will decrease the time required to construct voxel models. Copyright (2001) Australasian College of Physical Scientists and Engineers in Medicine

  5. Visual computed tomographic scoring of emphysema and its correlation with its diagnostic electrocardiographic sign: the frontal P vector.

    Science.gov (United States)

    Chhabra, Lovely; Sareen, Pooja; Gandagule, Amit; Spodick, David H

    2012-03-01

    Verticalization of the frontal P vector in patients older than 45 years is virtually diagnostic of pulmonary emphysema (sensitivity, 96%; specificity, 87%). We investigated the correlation of P vector and the computed tomographic visual score of emphysema (VSE) in patients with established diagnosis of chronic obstructive pulmonary disease/emphysema. High-resolution computed tomographic scans of 26 patients with emphysema (age, >45 years) were reviewed to assess the type and extent of emphysema using the subjective visual scoring. Electrocardiograms were independently reviewed to determine the frontal P vector. The P vector and VSE were compared for statistical correlation. Both P vector and VSE were also directly compared with the forced expiratory volume at 1 second. The VSE and the orientation of the P vector (ÂP) had an overall significant positive correlation (r = +0.68; P = .0001) in all patients, but the correlation was very strong in patients with predominant lower-lobe emphysema (r = +0.88; P = .0004). Forced expiratory volume at 1 second and ÂP had almost a linear inverse correlation in predominant lower-lobe emphysema (r = -0.92; P vertical ÂP and predominant lower-lobe emphysema reflects severe obstructive lung dysfunction. Copyright © 2012 Elsevier Inc. All rights reserved.

  6. Tomographic methods in nuclear medicine

    International Nuclear Information System (INIS)

    Ahluwalia, B.D.

    1989-01-01

    This book is a review of the various approaches to tomographic imaging that have been pursued in nuclear medicine. The evolution of single photon emission computed tomography (SPECT) is discussed in detail, and the major classes of instrumentation are represented. A section on positron emission tomography is also included, but is rather brief and may serve only as a general introduction

  7. Reconstruction of tomographic image from x-ray projections of a few views

    International Nuclear Information System (INIS)

    Kobayashi, Fujio; Yamaguchi, Shoichiro

    1982-01-01

    Computer tomographs have progressed rapidly, and in the latest high performance types, the photographing time has been shortened to less than 5 sec, but the clear images of hearts have not yet been obtained. The X-ray tomographs used so far irradiate X-ray from many directions and measure the projected data, but by limiting projection direction to a small number, it was planned to shorter the X-ray photographing time and to reduce X-ray exposure as the objective of this study. In this paper, a method is proposed, by which tomographic images are reconstructed from projected data in a small number of direction by generalized inverse matrix penalty method. This method is the calculation method newly devised by the authors for this purpose. It is a kind of the nonlinear planning method added with the restrictive condition using a generalized inverse matrix, and it is characterized by the simple calculation procedure and rapid convergence. Moreover, the effect on reconstructed images when errors are included in projected data was examined. Also, the simple computer simulation to reconstruct tomographic images using the projected data in four directions was performed, and the usefulness of this method was confirmed. It contributes to the development of superhigh speed tomographs in future. (Kako, I.)

  8. Comparison of primary thyroid lymphoma with anaplastic thyroid carcinoma on computed tomographic imaging

    International Nuclear Information System (INIS)

    Ishikawa, Hitoshi; Mitsuhashi, Norio; Niibe, Hideo

    2002-01-01

    Primary non-Hodgkin's lymphoma (LY) and anaplastic carcinoma (AC) of the thyroid gland are rare malignant tumors, and the initial symptoms of these diseases are very similar. The aim of our study was to compare the characteristics of the two diseases using computed tomographic (CT) scans in order to make an accurate differential diagnosis. Ten patients with LY and 10 with AC were analyzed. Differences in the CT findings of the two diseases were evaluated before treatment and statistically tested with either Student's t-test or the chi-square test. In the analysis of characteristics of CT imaging, the existence of calcification and necrosis, and heterogeneous tumor were dominant findings in AC, and there was a statistically significant difference in frequency between the two diseases (p<0.01). Calcification detected in AC was usually multiple and/or gross (mean size: φ8.2 mm). All lymphadenopathies were delineated as having the same homogeneous attenuation as the tumors in the thyroid gland in LY, but were shown as irregular rim enhancement in AC. The CT features of the two diseases are characteristic in terms of calcification, necrosis, and tumor composition. Evaluation by means of CT imaging is useful in distinguishing between LY and AC. (author)

  9. Transient ischemic attacks with and without a relevant infarct on computed tomographic scans cannot be distinguished clinically. Dutch Transient Ischemic Attack Study Group

    NARCIS (Netherlands)

    Koudstaal, P. J.; van Gijn, J.; Lodder, J.; Frenken, W. G.; Vermeulen, M.; Franke, C. L.; Hijdra, A.; Bulens, C.

    1991-01-01

    We prospectively studied clinical and computed tomographic (CT) scan findings in 79 patients with a transient ischemic attack (TIA) and a relevant cerebral infarction on CT, also known as cerebral infarction with transient signs (CITS). We compared the results with those of 527 concurrent patients

  10. Three-dimensional computed tomographic volumetry precisely predicts the postoperative pulmonary function.

    Science.gov (United States)

    Kobayashi, Keisuke; Saeki, Yusuke; Kitazawa, Shinsuke; Kobayashi, Naohiro; Kikuchi, Shinji; Goto, Yukinobu; Sakai, Mitsuaki; Sato, Yukio

    2017-11-01

    It is important to accurately predict the patient's postoperative pulmonary function. The aim of this study was to compare the accuracy of predictions of the postoperative residual pulmonary function obtained with three-dimensional computed tomographic (3D-CT) volumetry with that of predictions obtained with the conventional segment-counting method. Fifty-three patients scheduled to undergo lung cancer resection, pulmonary function tests, and computed tomography were enrolled in this study. The postoperative residual pulmonary function was predicted based on the segment-counting and 3D-CT volumetry methods. The predicted postoperative values were compared with the results of postoperative pulmonary function tests. Regarding the linear correlation coefficients between the predicted postoperative values and the measured values, those obtained using the 3D-CT volumetry method tended to be higher than those acquired using the segment-counting method. In addition, the variations between the predicted and measured values were smaller with the 3D-CT volumetry method than with the segment-counting method. These results were more obvious in COPD patients than in non-COPD patients. Our findings suggested that the 3D-CT volumetry was able to predict the residual pulmonary function more accurately than the segment-counting method, especially in patients with COPD. This method might lead to the selection of appropriate candidates for surgery among patients with a marginal pulmonary function.

  11. The research of clinical application of computed tomographic virtual gastroscopy

    International Nuclear Information System (INIS)

    Zhang Lei; Pan Zhenyu; Zhai Xiaoli; Gu Hua; Wang Yajie; Ding Yi; Wang Li; Liang Ying; Zhai Renyou

    2000-01-01

    Objective: To investigate the values, methods and findings of computed tomographic virtual gastroscopy (CTVG). Methods: Sixty-nine patients underwent the examination of spiral CT after charged air into stomachs in different cubage. The CT scan conditions were collimating width 3 mm, pitch 1.2 - 2.5, scanning speed 0.8 s/360 degree, the raw data of CT volume scan was reconstructed in overlapping rate 33% - 67%. Then the images of CTVG were built using navigator software (GE AG, USA). Results: The accuracy, sensitivity, and specificity of CTVG were 92.8%, 96.4%, and 78.6%, respectively. CTVG corresponded well with fibrous gastroscopy and specimens in demonstrating the gastric lesions. CTVG was provided with the ability of revealing the tiny lesions of chronic atrophic gastritis, chronic erosive gastritis, chronic proliferative gastritis, and acute hemorrhagic gastritis in some degree. The high quality imaging of CTVG could be obtained in condition of collimating width 3 mm, pitch 1.2 - 1.5, overlapping 50% - 67%, well hold-breath, gastric cubage in full and feasible scan positions. Conclusion: CTVG is a rising means of gastric examination and has great value in clinic applications

  12. Influence of Heat Treatment of Nickel-Titanium Rotary Endodontic Instruments on Apical Preparation: A Micro-Computed Tomographic Study.

    Science.gov (United States)

    de Almeida, Bernardo Corrêa; Ormiga, Fabíola; de Araújo, Marcos César Pimenta; Lopes, Ricardo Tadeu; Lima, Inayá Corrêa Barbosa; dos Santos, Bernardo Camargo; Gusman, Heloisa

    2015-12-01

    The aim of this study was to make a 3-dimensional comparison of the canal transportation and changes in apical geometry using micro-computed tomographic imaging after canal preparation with K3 (SybronEndo, Orange, CA) and K3XF (SybronEndo) file systems. Twenty-eight mandibular molars were randomly divided into 2 groups according to the rotary system used in instrumentation: K3 or K3XF. The specimens were scanned by micro-computed tomographic imaging before and after instrumentation. Images before and after instrumentation from each group were compared with regard to canal volume, surface area, and structure model index (SMI) (paired t test, P instrumentation, the canals from each group were compared regarding the changes in volume, surface area, SMI, and canal transportation in the last 4 apical mm (t test, P Instrumentation with the 2 rotary systems significantly changed the canal volume, surface area, and SMI (P instrument types concerning these parameters (P > .05). There were no significant differences between the 2 groups with regard to canal transportation in the last 4 apical mm (P > .05). Both rotary systems showed adequate canal preparations with reduced values of canal transportation. Heat treatment did not influence changes in root canal geometry in the apical region. Copyright © 2015 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  13. Prediction of Clinical Outcome After Acute Ischemic Stroke: The Value of Repeated Noncontrast Computed Tomography, Computed Tomographic Angiography, and Computed Tomographic Perfusion.

    Science.gov (United States)

    Dankbaar, Jan W; Horsch, Alexander D; van den Hoven, Andor F; Kappelle, L Jaap; van der Schaaf, Irene C; van Seeters, Tom; Velthuis, Birgitta K

    2017-09-01

    Early prediction of outcome in acute ischemic stroke is important for clinical management. This study aimed to compare the relationship between early follow-up multimodality computed tomographic (CT) imaging and clinical outcome at 90 days in a large multicenter stroke study. From the DUST study (Dutch Acute Stroke Study), patients were selected with (1) anterior circulation occlusion on CT angiography (CTA) and ischemic deficit on CT perfusion (CTP) on admission, and (2) day 3 follow-up noncontrast CT, CTP, and CTA. Follow-up infarct volume on noncontrast CT, poor recanalization on CTA, and poor reperfusion on CTP (mean transit time index ≤75%) were related to unfavorable outcome after 90 days defined as modified Rankin Scale 3 to 6. Four multivariable models were constructed: (1) only baseline variables (model 1), (2) model 1 with addition of infarct volume, (3) model 1 with addition of recanalization, and (4) model 1 with addition of reperfusion. Area under the curves of the receiver operating characteristic curves of the models were compared using the DeLong test. A total of 242 patients were included. Poor recanalization was found in 21%, poor reperfusion in 37%, and unfavorable outcome in 44%. The area under the curve of the receiver operating characteristic curve without follow-up imaging was 0.81, with follow-up noncontrast CT 0.85 ( P =0.02), CTA 0.86 ( P =0.01), and CTP 0.86 ( P =0.01). All 3 follow-up imaging modalities improved outcome prediction compared with no imaging. There was no difference between the imaging models. Follow-up imaging after 3 days improves outcome prediction compared with prediction based on baseline variables alone. CTA recanalization and CTP reperfusion do not outperform noncontrast CT at this time point. URL: http://www.clinicaltrials.gov. Unique identifier: NCT00880113. © 2017 American Heart Association, Inc.

  14. Computed tomographic analysis of urinary calculi

    International Nuclear Information System (INIS)

    Naito, Akira; Ito, Katsuhide; Ito, Shouko

    1986-01-01

    Computed tomography (CT) was employed in an effort to analyze the chemical composition of urinary calculi. Twenty-three surgically removed calculi were scanned in a water bath (in vitro study). Forteen of them in the body were scanned (in vivo study). The calculi consisted of four types: mixed calcium oxalate and phosphate, mixed calcium carbonate and phosphate, magnesium ammonium phosphate, and uric acid. The in vitro study showed that the mean and maximum CT values of uric acid stones were significantly lower than those of the other three types of stones. This indicated that stones with less than 450 HU are composed of uric acid. In an in vivo study, CT did not help to differentiate the three types of urinary calculi, except for uric acid stones. Regarding the mean CT values, there was no correlation between in vitro and in vivo studies. An experiment with commercially available drugs showed that CT values of urinary calculi were not dependent upon the composition, but dependent upon the density of the calculi. (Namekawa, K.)

  15. Cost-Effectiveness of Computed Tomographic Colonography: A Prospective Comparison with Colonoscopy

    International Nuclear Information System (INIS)

    Arnesen, R.B.; Ginnerup-Pedersen, B.; Poulsen, P.B.; Benzon, K. von; Adamsen, S.; Laurberg, S.; Hart-Hansen, O.

    2007-01-01

    Purpose: To estimate the cost-effectiveness of detecting colorectal polyps with computed tomographic colonography (CTC) and subsequent polypectomy with primary colonoscopy (CC), using CC as the alternative strategy. Material and Methods: A marginal analysis was performed regarding 103 patients who had had CTC prior to same-day CC at two hospitals, H-I (n 53) and H-II (n = 50). The patients were randomly chosen from surveillance and symptomatic study populations (148 at H-I and 231 at H-II). Populations, organizations, and procedures were compared. Cost data on time consumption, medication, and minor equipment were collected prospectively, while data on salaries and major equipment were collected retrospectively. The effect was the (previously published) sensitivities of CTC and CC for detection of colorectal polyps ≥6 mm (H-I, n = 148) or ≥5 mm (H-II, n = 231). Results: Thirteen patients at each center had at least one colorectal polyp ≥6 mm or ≥5 mm. CTC was the cost-effective alternative at H-I (Euro 187 vs. Euro 211), while CC was the cost-effective alternative at H-II (Euro 239 vs. Euro 192). The cost-effectiveness (costs per finding) mainly depended on the sensitivity of CTC and CC, but the depreciation of equipment and the staff's use of time were highly influential as well. Conclusion: Detection of colorectal polyps ≥6 mm or ≥5 mm with CTC, followed by polypectomy by CC, can be performed cost-effectively at some institutions with the appropriate hardware and organization keywords

  16. Radiographic and computed tomographic demonstration of pseudotumor cerebri due to rapid weight gain in a child with pelvic rhabdomyosarcoma

    Energy Technology Data Exchange (ETDEWEB)

    Berdon, W.E.; Barker, D.H.; Barash, F.S.

    1982-06-01

    Rapid weight gain in a malnourished child can be associated with suture diastasis in the pattern of pseudotumor cerebri; this has been previously reported in deprivational dwarfism and cystic fibrosis. In a child with pelvic rhabdomyosarcoma, skull radiographs and cranial computed tomographic (CT) scans were available prior to a period of rapid weight gain induced by hyperalimentation. Suture diastasis developed and repeat CT scans showed this to be accompanied by smaller ventricles.

  17. Radiographic and computed tomographic demonstration of pseudotumor cerebri due to rapid weight gain in a child with pelvic rhabdomyosarcoma

    International Nuclear Information System (INIS)

    Berdon, W.E.; Barker, D.H.; Barash, F.S.

    1982-01-01

    Rapid weight gain in a malnourished child can be associated with suture diastasis in the pattern of pseudotumor cerebri; this has been previously reported in deprivational dwarfism and cystic fibrosis. In a child with pelvic rhabdomyosarcoma, skull radiographs and cranial computed tomographic (CT) scans were available prior to a period of rapid weight gain induced by hyperalimentation. Suture diastasis developed and repeat CT scans showed this to be accompanied by smaller ventricles

  18. Inspiratory and expiratory computed tomographic volumetry for lung volume reduction surgery.

    Science.gov (United States)

    Morimura, Yuki; Chen, Fengshi; Sonobe, Makoto; Date, Hiroshi

    2013-06-01

    Three-dimensional (3D) computed tomographic (CT) volumetry has been introduced into the field of thoracic surgery, and a combination of inspiratory and expiratory 3D-CT volumetry provides useful data on regional pulmonary function as well as the volume of individual lung lobes. We report herein a case of a 62-year-old man with severe emphysema who had undergone lung volume reduction surgery (LVRS) to assess this technique as a tool for the evaluation of regional lung function and volume before and after LVRS. His postoperative pulmonary function was maintained in good condition despite a gradual slight decrease 2 years after LVRS. This trend was also confirmed by a combination of inspiratory and expiratory 3D-CT volumetry. We confirm that a combination of inspiratory and expiratory 3D-CT volumetry might be effective for the preoperative assessment of LVRS in order to determine the amount of lung tissue to be resected as well as for postoperative evaluation. This novel technique could, therefore, be used more widely to assess local lung function.

  19. Construction of tomographic head model using sectioned photographic images of cadaver

    International Nuclear Information System (INIS)

    Lee, Choon Sik; Lee, Jai Ki; Park, Jin Seo; Chung, Min Suk

    2004-01-01

    Tomographic models are currently the most complete, developed and realistic models of the human anatomy. They have been used to estimate organ doses for diagnostic radiation examination and radiotherapy treatment planning, and radiation protection. The quality of original anatomic images is a key factor to build a quality tomographic model. Computed tomography (CT) and magnetic resonance imaging (MRI) scan, from which most of current tomographic models are constructed, have their inherent shortcomings. In this study, a tomographic model of Korean adult male head was constructed by using serially sectioned photographs of cadaver. The cadaver was embedded, frozen, serially sectioned and photographed by high resolution digital camera at 0.2 mm interval. The contours of organs and tissues in photographs were segmented by several trained anatomists. The 120 segmented images of head at 2mm interval were converted into binary files and ported into Monte Carlo code to perform an example calculation of organ dose. Whole body tomographic model will be constructed by using the procedure developed in this study

  20. Clinical usefulness of facial soft tissues thickness measurement using 3D computed tomographic images

    International Nuclear Information System (INIS)

    Jeong, Ho Gul; Kim, Kee Deog; Hu, Kyung Seok; Lee, Jae Bum; Park, Hyok; Han, Seung Ho; Choi, Seong Ho; Kim, Chong Kwan; Park, Chang Seo

    2006-01-01

    To evaluate clinical usefulness of facial soft tissue thickness measurement using 3D computed tomographic images. One cadaver that had sound facial soft tissues was chosen for the study. The cadaver was scanned with a Helical CT under following scanning protocols about slice thickness and table speed: 3 mm and 3 mm/sec, 5 mm and 5 mm/sec, 7 mm and 7 mm/sec. The acquired data were reconstructed 1.5, 2.5, 3.5 mm reconstruction interval respectively and the images were transferred to a personal computer. Using a program developed to measure facial soft tissue thickness in 3D image, the facial soft tissue thickness was measured. After the ten-time repeation of the measurement for ten times, repeated measure analysis of variance (ANOVA) was adopted to compare and analyze the measurements using the three scanning protocols. Comparison according to the areas was analysed by Mann-Whitney test. There were no statistically significant intraobserver differences in the measurements of the facial soft tissue thickness using the three scanning protocols (p>0.05). There were no statistically significant differences between measurements in the 3 mm slice thickness and those in the 5 mm, 7 mm slice thickness (p>0.05). There were statistical differences in the 14 of the total 30 measured points in the 5 mm slice thickness and 22 in the 7 mm slice thickness. The facial soft tissue thickness measurement using 3D images of 7 mm slice thickness is acceptable clinically, but those of 5 mm slice thickness is recommended for the more accurate measurement

  1. Seeing is believing: video classification for computed tomographic colonography using multiple-instance learning.

    Science.gov (United States)

    Wang, Shijun; McKenna, Matthew T; Nguyen, Tan B; Burns, Joseph E; Petrick, Nicholas; Sahiner, Berkman; Summers, Ronald M

    2012-05-01

    In this paper, we present development and testing results for a novel colonic polyp classification method for use as part of a computed tomographic colonography (CTC) computer-aided detection (CAD) system. Inspired by the interpretative methodology of radiologists using 3-D fly-through mode in CTC reading, we have developed an algorithm which utilizes sequences of images (referred to here as videos) for classification of CAD marks. For each CAD mark, we created a video composed of a series of intraluminal, volume-rendered images visualizing the detection from multiple viewpoints. We then framed the video classification question as a multiple-instance learning (MIL) problem. Since a positive (negative) bag may contain negative (positive) instances, which in our case depends on the viewing angles and camera distance to the target, we developed a novel MIL paradigm to accommodate this class of problems. We solved the new MIL problem by maximizing a L2-norm soft margin using semidefinite programming, which can optimize relevant parameters automatically. We tested our method by analyzing a CTC data set obtained from 50 patients from three medical centers. Our proposed method showed significantly better performance compared with several traditional MIL methods.

  2. [X-ray computed tomographic aspects of benign primary cerebral melanomas. Apropos of 4 cases].

    Science.gov (United States)

    Adam, P; Alberge, Y; Espagno, C; Bouzigues, J Y

    1986-02-01

    Benign primitive melanomas are rare tumours usually involving the leptomeninges. Four cranial localizations are reported: 2 tumours of the foramen magnum, 1 of the cerebellopontine angle and 1 supratentorial. The clinical symptomatology is variable according to the level. Slow medullary compression is frequent. One can emphasize the special and difficult problem of foramen magnum tumours that present with a very variable clinical status frequently simulating a non surgical disease of the central nervous system. The benign and primitive appearance of these tumours is evocated by the slow and favourable evolution and by the absence of extraneurologic melanotic tumour. Our purpose is essentially to emphasize the radiological and particularly the computed tomographic (CT) findings poorly described in the literature. Benign melanomas have resemblance with meningiomas: osseous or meningeal relationship, homogeneity and high density. On the other hand the angiography shows poor vascularization. One can think that a tumor simulating a meningioma by CT but not by angiography is perhaps a benign melanoma. The special problem of the radiological diagnosis of foramen magnum tumours is evocated: Computed myelography, tridimensional imaging by NMR.

  3. Tomographic images of cerebral blood flow using a slant hole collimator

    International Nuclear Information System (INIS)

    Wraight, E.P.; Barber, R.W.; Crossland, P.; Maltby, P.

    1983-01-01

    The feasibility of using a rotating slant hole (RSH) collimator on simple tomographic equipment such as a standard gamma camera interfaced to a general purpose Nuclear Medicine computer is reported for producing images of cerebral blood flow following the administration of 123 I-iodoamphetamine to patients. Initial studies produced satisfactory images, thus opening the possibility of tomographic cerebral blood flow imaging to centres not possessing sophisticated tomographic equipment. Planar resolution is superior to that reported for a 25 0 RSH collimator. Axial resolution is not as good at small source distances but is comparable at distances beyond 10 cm. Sensitivity is comparable to other RSH collimators and is similar to Technicare's parallel hole general all purpose collimator. (UK)

  4. Analysis of computer images in the presence of metals

    Science.gov (United States)

    Buzmakov, Alexey; Ingacheva, Anastasia; Prun, Victor; Nikolaev, Dmitry; Chukalina, Marina; Ferrero, Claudio; Asadchikov, Victor

    2018-04-01

    Artifacts caused by intensely absorbing inclusions are encountered in computed tomography via polychromatic scanning and may obscure or simulate pathologies in medical applications. To improve the quality of reconstruction if high-Z inclusions in presence, previously we proposed and tested with synthetic data an iterative technique with soft penalty mimicking linear inequalities on the photon-starved rays. This note reports a test at the tomographic laboratory set-up at the Institute of Crystallography FSRC "Crystallography and Photonics" RAS in which tomographic scans were successfully made of temporary tooth without inclusion and with Pb inclusion.

  5. Estimating multi-phase pore-scale characteristics from X-ray tomographic data using cluster analysis-based segmentation

    DEFF Research Database (Denmark)

    Wildenschild, D.; Culligan, K.A.; Christensen, Britt Stenhøj Baun

    2006-01-01

    present in grey-scale X-ray tomographic images. The approach is based on a cluster analysis technique, used in combination with various other filtering and skeletonization schemes. We apply this segmentation algorithm to analyze multiphase pore-scale flow subjects such as hysteresis and interfacial...... characterization. The results clearly illustrate the advantage of using X-ray tomography together with cluster analysis-based image processing techniques. We were able to obtain detailed information on pore scale distribution of air and water phases, as well as quantitative measures of air bubble size and air...... of individual pores and interfaces. However, separation of the various phases (fluids and solids) in the grey-scale tomographic images has posed a major problem to quantitative analysis of the data. We present an image processing technique that facilitates identification and separation of the various phases...

  6. The impact of reorienting cone-beam computed tomographic images in varied head positions on the coordinates of anatomical landmarks

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jae Hun; Jeong, Ho Gul; Hwang, Jae Joon; Lee, Jung Hee; Han, Sang Sun [Dept. of Oral and Maxillofacial Radiology, Yonsei University, College of Dentistry, Seoul (Korea, Republic of)

    2016-06-15

    The aim of this study was to compare the coordinates of anatomical landmarks on cone-beam computed tomographic (CBCT) images in varied head positions before and after reorientation using image analysis software. CBCT images were taken in a normal position and four varied head positions using a dry skull marked with 3 points where gutta percha was fixed. In each of the five radiographic images, reference points were set, 20 anatomical landmarks were identified, and each set of coordinates was calculated. Coordinates in the images from the normally positioned head were compared with those in the images obtained from varied head positions using statistical methods. Post-reorientation coordinates calculated using a three-dimensional image analysis program were also compared to the reference coordinates. In the original images, statistically significant differences were found between coordinates in the normal-position and varied-position images. However, post-reorientation, no statistically significant differences were found between coordinates in the normal-position and varied-position images. The changes in head position impacted the coordinates of the anatomical landmarks in three-dimensional images. However, reorientation using image analysis software allowed accurate superimposition onto the reference positions.

  7. Design and construction of the gamma ray transmission tomographer g-TAC-02

    International Nuclear Information System (INIS)

    Pavon Hernandez, Noriel; Ravelo Sanchez, Alberto; Idel, Pedro; Macias Perez, Rafael; Garcia Trapaga, Cesar; Campos Montenegro, Augusto

    2000-01-01

    An equipment for gamma ray transmission tomographer was designed and constructed in the Higher Institute of Nuclear Sciences and Technology. It was the g-TAC-01, based on a nuclear instrumentation, a mechanic instrumentation, and the control of the system from a personal computer. This first version permitted to obtain the know how of the technology of construction of equipment for tomography. The present work describes the second version of the gamma ray transmission tomographer: the g-TAC-02, with very important upgrading in the control session. Now the control system is a microcontroller based, electronic control system, designed to work in multiples forms: manual, automatic and with the computer

  8. Identification of High-Risk Plaques Destined to Cause Acute Coronary Syndrome Using Coronary Computed Tomographic Angiography and Computational Fluid Dynamics.

    Science.gov (United States)

    Lee, Joo Myung; Choi, Gilwoo; Koo, Bon-Kwon; Hwang, Doyeon; Park, Jonghanne; Zhang, Jinlong; Kim, Kyung-Jin; Tong, Yaliang; Kim, Hyun Jin; Grady, Leo; Doh, Joon-Hyung; Nam, Chang-Wook; Shin, Eun-Seok; Cho, Young-Seok; Choi, Su-Yeon; Chun, Eun Ju; Choi, Jin-Ho; Nørgaard, Bjarne L; Christiansen, Evald H; Niemen, Koen; Otake, Hiromasa; Penicka, Martin; de Bruyne, Bernard; Kubo, Takashi; Akasaka, Takashi; Narula, Jagat; Douglas, Pamela S; Taylor, Charles A; Kim, Hyo-Soo

    2018-03-14

    We investigated the utility of noninvasive hemodynamic assessment in the identification of high-risk plaques that caused subsequent acute coronary syndrome (ACS). ACS is a critical event that impacts the prognosis of patients with coronary artery disease. However, the role of hemodynamic factors in the development of ACS is not well-known. Seventy-two patients with clearly documented ACS and available coronary computed tomographic angiography (CTA) acquired between 1 month and 2 years before the development of ACS were included. In 66 culprit and 150 nonculprit lesions as a case-control design, the presence of adverse plaque characteristics (APC) was assessed and hemodynamic parameters (fractional flow reserve derived by coronary computed tomographic angiography [FFR CT ], change in FFR CT across the lesion [△FFR CT ], wall shear stress [WSS], and axial plaque stress) were analyzed using computational fluid dynamics. The best cut-off values for FFR CT , △FFR CT , WSS, and axial plaque stress were used to define the presence of adverse hemodynamic characteristics (AHC). The incremental discriminant and reclassification abilities for ACS prediction were compared among 3 models (model 1: percent diameter stenosis [%DS] and lesion length, model 2: model 1 + APC, and model 3: model 2 + AHC). The culprit lesions showed higher %DS (55.5 ± 15.4% vs. 43.1 ± 15.0%; p stress than nonculprit lesions (all p values statistic [c-index] 0.789 vs. 0.747; p = 0.014) and reclassification abilities (category-free net reclassification index 0.287; p = 0.047; relative integrated discrimination improvement 0.368; p < 0.001) than model 2. Lesions with both APC and AHC showed significantly higher risk of the culprit for subsequent ACS than those with no APC/AHC (hazard ratio: 11.75; 95% confidence interval: 2.85 to 48.51; p = 0.001) and with either APC or AHC (hazard ratio: 3.22; 95% confidence interval: 1.86 to 5.55; p < 0.001). Noninvasive hemodynamic assessment enhanced

  9. Construction of Korean male tomographic model segmented from PET-CT data

    International Nuclear Information System (INIS)

    Lee, Choon Sik; Park, Sang Kyun; Lee, Jai Ki

    2004-01-01

    Tomographic human models provide currently the most realistic representation of human anatomy for radiation dosimetry calculation. Most of the models have been constructed by using computed tomographic (CT) or magnetic resonance (MR) images obtained from a single individual. Each scan has its inherent advantages and disadvantages. CT scan gives a considerable radiation dose to a subject, and MR scan takes too long time to get clear images of an immobile subject. An emerging source of medical images for the construction of tomographic models is PET-CT, which is performed when looking for cancer. In this study, a tomographic model of Korean adult male was developed by processing whole-body CT images of a PET-CT-scanned healthy volunteer. The 343 slices of the CT images were semi-automatically segmented layer by layer using a graphic software and screen digitizer. The 3rd Korean tomographic model, named KRMAN-2, consisting of 300x150x344 voxels of a size of 2x2x5mm 3 , was constructed. Examples of application to Monte Carlo radiation dosimetry calculation in idealized whole-body irradiations were given and discussed

  10. Segmentation-DrivenTomographic Reconstruction

    DEFF Research Database (Denmark)

    Kongskov, Rasmus Dalgas

    such that the segmentation subsequently can be carried out by use of a simple segmentation method, for instance just a thresholding method. We tested the advantages of going from a two-stage reconstruction method to a one stage segmentation-driven reconstruction method for the phase contrast tomography reconstruction......The tomographic reconstruction problem is concerned with creating a model of the interior of an object from some measured data, typically projections of the object. After reconstructing an object it is often desired to segment it, either automatically or manually. For computed tomography (CT...

  11. Radiographic and tomographic study of the elbow joint in dogs

    International Nuclear Information System (INIS)

    Sendyk-Grunkraut, Alessandra; Martin, Claudia M.; Souza, Alexandre N.A.; Patricio, Geni Cristina F.; Lorigados, Carla A.B.; Matera, Julia M.; Fonseca-Pinto, Ana C.B.C.

    2017-01-01

    Elbow dysplasia disease includes an united anconeal process, fragmented medial coronoid process, osteochondrosis of humeral trochlea, articular incongruity and degenerative joint disease. The aim of this study was to present detailed morphologic and morphometric aspects of the elbow joint in dog in clinical and correlate with radiographic and tomographic (CT) exam. Inter-observer variation for articular incongruity measurements by CT, comparative analysis in the radiographic exam, angle in ulnar notch and its comparative analysis between radiographic and tomographic agreement examination in 44 elbow of dogs with different ages were evaluated. The statistics analyses included the kappa coefficient and interclass correlation and Fischer's test and McNemar's test. It was evidenced that individual performance of each radiographic incidence had poor agreement with the tomographic exam, suggesting that the accomplishment of more than two radiograph views are needed. There was no agreement between the three evaluators in the ulnar notch angle at radiographic and tomographic exams. However, there was good/moderate agreement for articular incongruity measurement in the sagittal plane between evaluators. It was possible to conclude that none of the five radiographic incidences was better than the others for radiographic analysis because each incidence had a better identification of a particular elbow compartment; measurements at the tomographic exam to evaluate radioulnar incongruity had no reproductiveness in the frontal plane, but in sagittal plan had a good/moderate agreement between observers and the angle in ulnar notch presented no repeatability at radiographic exam and no reproductiveness at tomographic exam. (author)

  12. Central tarsal bone fractures in horses not used for racing: Computed tomographic configuration and long-term outcome of lag screw fixation

    OpenAIRE

    Gunst, S; Del Chicca, Francesca; Fürst, Anton; Kuemmerle, Jan M

    2016-01-01

    REASONS FOR PERFORMING STUDY: There are no reports on the configuration of equine central tarsal bone fractures based on cross-sectional imaging and clinical and radiographic long-term outcome after internal fixation. OBJECTIVES: To report clinical, radiographic and computed tomographic findings of equine central tarsal bone fractures and to evaluate the long-term outcome of internal fixation. STUDY DESIGN: Retrospective case series. METHODS: All horses diagnosed with a central tarsa...

  13. Computed tomographic features of 23 sporadic cases with Legionella pneumophila pneumonia

    International Nuclear Information System (INIS)

    Yu Hui; Higa, Futoshi; Hibiya, Kenji; Furugen, Makoto; Sato, Yoko; Shinzato, Takashi; Haranaga, Shusaku; Yara, Satomi; Tateyama, Masao; Fujita, Jiro; Li, Huiping

    2010-01-01

    Objective: To describe the chest computed tomographic (CT) findings of Legionella pneumophila pneumonia. Methods: CT scans obtained from 23 sporadic cases of L. pneumophila pneumonia were retrospectively reviewed. Chest CT findings were analyzed with regard to the patterns and distributions of pulmonary abnormalities. We also analyzed the histopathology of lungs from guinea pigs with experimentally induced L. pneumophila pneumonia. Results: Consolidation and ground-glass opacity (GGO) were the main findings of CT scans in L. pneumophila pneumonia. The distribution of opacities was categorized as non-segmental (n = 20) and segmental (n = 4). Non-segmental distribution may follow an onset of segmental distribution. Pleural effusion was observed in 14 (58.3%) patients, of which 13 were accompanied with non-segmental distribution. Abscess formation was observed in only one immunocompromised patient. In the animal pneumonia model, the lesions comprised of terminal bronchioles, alveolar spaces, and interstitia. Small bacilli were observed to be contained by many macrophages within the alveoli. Conclusion: Non-segmental distribution was significantly more frequent than segmental distribution in L. pneumophila pneumonia. It is possible that L. pneumophila infection initially results in segmental pneumonia, which progresses to typical non-segmental distribution.

  14. Computed tomographic features of 23 sporadic cases with Legionella pneumophila pneumonia

    Energy Technology Data Exchange (ETDEWEB)

    Yu Hui [Department of Respiratory Diseases, Shanghai Pneumology Hospital, Tongji University, Shanghai (China); Higa, Futoshi; Hibiya, Kenji; Furugen, Makoto [Department of Medicine and Therapeutics, Control and Prevention of Infectious Diseases (First Department of Internal Medicine), Faculty of Medicine, University of the Ryukyus, Okinawa (Japan); Sato, Yoko [Tomishiro Chuo Hospital, Okinawa (Japan); Shinzato, Takashi [Nakagami General Hospital, Okinawa (Japan); Haranaga, Shusaku; Yara, Satomi; Tateyama, Masao [Department of Medicine and Therapeutics, Control and Prevention of Infectious Diseases (First Department of Internal Medicine), Faculty of Medicine, University of the Ryukyus, Okinawa (Japan); Fujita, Jiro, E-mail: fujita@med.u-ryukyu.ac.j [Department of Medicine and Therapeutics, Control and Prevention of Infectious Diseases (First Department of Internal Medicine), Faculty of Medicine, University of the Ryukyus, Okinawa (Japan); Li, Huiping [Department of Respiratory Diseases, Shanghai Pneumology Hospital, Tongji University, Shanghai (China)

    2010-06-15

    Objective: To describe the chest computed tomographic (CT) findings of Legionella pneumophila pneumonia. Methods: CT scans obtained from 23 sporadic cases of L. pneumophila pneumonia were retrospectively reviewed. Chest CT findings were analyzed with regard to the patterns and distributions of pulmonary abnormalities. We also analyzed the histopathology of lungs from guinea pigs with experimentally induced L. pneumophila pneumonia. Results: Consolidation and ground-glass opacity (GGO) were the main findings of CT scans in L. pneumophila pneumonia. The distribution of opacities was categorized as non-segmental (n = 20) and segmental (n = 4). Non-segmental distribution may follow an onset of segmental distribution. Pleural effusion was observed in 14 (58.3%) patients, of which 13 were accompanied with non-segmental distribution. Abscess formation was observed in only one immunocompromised patient. In the animal pneumonia model, the lesions comprised of terminal bronchioles, alveolar spaces, and interstitia. Small bacilli were observed to be contained by many macrophages within the alveoli. Conclusion: Non-segmental distribution was significantly more frequent than segmental distribution in L. pneumophila pneumonia. It is possible that L. pneumophila infection initially results in segmental pneumonia, which progresses to typical non-segmental distribution.

  15. Relationship of Hypertension to Coronary Atherosclerosis and Cardiac Events in Patients With Coronary Computed Tomographic Angiography.

    Science.gov (United States)

    Nakanishi, Rine; Baskaran, Lohendran; Gransar, Heidi; Budoff, Matthew J; Achenbach, Stephan; Al-Mallah, Mouaz; Cademartiri, Filippo; Callister, Tracy Q; Chang, Hyuk-Jae; Chinnaiyan, Kavitha; Chow, Benjamin J W; DeLago, Augustin; Hadamitzky, Martin; Hausleiter, Joerg; Cury, Ricardo; Feuchtner, Gudrun; Kim, Yong-Jin; Leipsic, Jonathon; Kaufmann, Philipp A; Maffei, Erica; Raff, Gilbert; Shaw, Leslee J; Villines, Todd C; Dunning, Allison; Marques, Hugo; Pontone, Gianluca; Andreini, Daniele; Rubinshtein, Ronen; Bax, Jeroen; Jones, Erica; Hindoyan, Niree; Gomez, Millie; Lin, Fay Y; Min, James K; Berman, Daniel S

    2017-08-01

    Hypertension is an atherosclerosis factor and is associated with cardiovascular risk. We investigated the relationship between hypertension and the presence, extent, and severity of coronary atherosclerosis in coronary computed tomographic angiography and cardiac events risk. Of 17 181 patients enrolled in the CONFIRM registry (Coronary CT Angiography Evaluation for Clinical Outcomes: An International Multicenter Registry) who underwent ≥64-detector row coronary computed tomographic angiography, we identified 14 803 patients without known coronary artery disease. Of these, 1434 hypertensive patients were matched to 1434 patients without hypertension. Major adverse cardiac events risk of hypertension and non-hypertensive patients was evaluated with Cox proportional hazards models. The prognostic associations between hypertension and no-hypertension with increasing degree of coronary stenosis severity (nonobstructive or obstructive ≥50%) and extent of coronary artery disease (segment involvement score of 1-5, >5) was also assessed. Hypertension patients less commonly had no coronary atherosclerosis and more commonly had nonobstructive and 1-, 2-, and 3-vessel disease than the no-hypertension group. During a mean follow-up of 5.2±1.2 years, 180 patients experienced cardiac events, with 104 (2.0%) occurring in the hypertension group and 76 (1.5%) occurring in the no-hypertension group (hazard ratios, 1.4; 95% confidence intervals, 1.0-1.9). Compared with no-hypertension patients without coronary atherosclerosis, hypertension patients with no coronary atherosclerosis and obstructive coronary disease tended to have higher risk of cardiac events. Similar trends were observed with respect to extent of coronary artery disease. Compared with no-hypertension patients, hypertensive patients have increased presence, extent, and severity of coronary atherosclerosis and tend to have an increase in major adverse cardiac events. © 2017 American Heart Association, Inc.

  16. Fibromuscular dysplasia in living renal donors: Still a challenge to computed tomographic angiography

    International Nuclear Information System (INIS)

    Blondin, D.; Lanzman, R.; Schellhammer, F.; Oels, M.; Grotemeyer, D.; Baldus, S.E.; Rump, L.C.; Sandmann, W.; Voiculescu, A.

    2010-01-01

    Background: Computed tomographic angiography has become the standard evaluating method of potential living renal donors in most centers. Although incidence of fibromuscular dysplasia is low (3.5-6%), this pathology may be relevant for success of renal transplantation. The incidence of FMD in our population of LRD and reliability of CTA for detecting vascular pathology were the aims of this study. Materials and methods: 101 living renal donors, examined between 7/2004 and 9/2008 by CTA, were included in a retrospective evaluation. The examinations were carried out using a 64 Multi-detector CT (Siemens Medical Solutions, Erlangen). The presence or absence of the characteristic signs of fibromuscular dysplasia, as 'string-of-beads' appearance, focal stenosis or aneurysms, were assessed and graded from mild (=1) to severe (=3). Furthermore, vascular anatomy and arterial stenosis were investigated in this study. Retrospective analysis of CTA and ultrasound were compared with operative and histological reports. Results: Four cases of fibromuscular dysplasia (incidence 3.9%) in 101 renal donors were diagnosed by transplanting surgeons and histopathology, respectively. Three cases could be detected by CTA. In one donor even retrospective analysis of CTA was negative. Ten accessory arteries, 14 venous anomalies and 12 renal arteries stenosis due to atherosclerosis were diagnosed by CTA and could be confirmed by the operative report. Conclusion: CTA is sufficient for detection of hemodynamic relevant stenosis and vascular anatomy. Only one patient with a mild form of FMD was under estimated. Therefore, if the CTA shows slightest irregularities which are not typical for atherosclerotic lesions, further diagnostic work up by DSA might still be necessary.

  17. Fibromuscular dysplasia in living renal donors: Still a challenge to computed tomographic angiography

    Energy Technology Data Exchange (ETDEWEB)

    Blondin, D., E-mail: blondin@med.uni-duesseldorf.d [Institute of Radiology, University Hospital Duesseldorf, Moorenstr. 5, D-40225 Duesseldorf (Germany); Lanzman, R.; Schellhammer, F. [Institute of Radiology, University Hospital Duesseldorf, Moorenstr. 5, D-40225 Duesseldorf (Germany); Oels, M. [Department of Nephrology (Germany); Grotemeyer, D. [Department of Vascular Surgery and Renal Transplantation (Germany); Baldus, S.E. [Institute of Pathology (Germany); Rump, L.C. [Department of Nephrology (Germany); Sandmann, W. [Department of Vascular Surgery and Renal Transplantation (Germany); Voiculescu, A. [Department of Nephrology (Germany)

    2010-07-15

    Background: Computed tomographic angiography has become the standard evaluating method of potential living renal donors in most centers. Although incidence of fibromuscular dysplasia is low (3.5-6%), this pathology may be relevant for success of renal transplantation. The incidence of FMD in our population of LRD and reliability of CTA for detecting vascular pathology were the aims of this study. Materials and methods: 101 living renal donors, examined between 7/2004 and 9/2008 by CTA, were included in a retrospective evaluation. The examinations were carried out using a 64 Multi-detector CT (Siemens Medical Solutions, Erlangen). The presence or absence of the characteristic signs of fibromuscular dysplasia, as 'string-of-beads' appearance, focal stenosis or aneurysms, were assessed and graded from mild (=1) to severe (=3). Furthermore, vascular anatomy and arterial stenosis were investigated in this study. Retrospective analysis of CTA and ultrasound were compared with operative and histological reports. Results: Four cases of fibromuscular dysplasia (incidence 3.9%) in 101 renal donors were diagnosed by transplanting surgeons and histopathology, respectively. Three cases could be detected by CTA. In one donor even retrospective analysis of CTA was negative. Ten accessory arteries, 14 venous anomalies and 12 renal arteries stenosis due to atherosclerosis were diagnosed by CTA and could be confirmed by the operative report. Conclusion: CTA is sufficient for detection of hemodynamic relevant stenosis and vascular anatomy. Only one patient with a mild form of FMD was under estimated. Therefore, if the CTA shows slightest irregularities which are not typical for atherosclerotic lesions, further diagnostic work up by DSA might still be necessary.

  18. Middle east respiratory syndrome-corona virus infection: A case report of sieral computed tomographic findings in a young male patient

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Won Jin; Lee, Ki Nam; Kang, Eun Ju; Lee, Hyuck [Dong A University Hospital, Busan (Korea, Republic of)

    2016-02-15

    Radiologic findings of Middle East respiratory syndrome (MERS), a novel coronavirus infection, have been rarely reported. We report a 30-year-old male presented with fever, abdominal pain, and diarrhea, who was diagnosed with MERS. A chest computed tomographic scan revealed rapidly developed multifocal nodular consolidations with ground-glass opacity halo and mixed consolidation, mainly in the dependent and peripheral areas. After treatment, follow-up imaging showed that these abnormalities markedly decreased but fibrotic changes developed.

  19. Optical Computed-Tomographic Microscope for Three-Dimensional Quantitative Histology

    Directory of Open Access Journals (Sweden)

    Ravil Chamgoulov

    2004-01-01

    Full Text Available A novel optical computed‐tomographic microscope has been developed allowing quantitative three‐dimensional (3D imaging and analysis of fixed pathological material. Rather than a conventional two‐dimensional (2D image, the instrument produces a 3D representation of fixed absorption‐stained material, from which quantitative histopathological features can be measured more accurately. The accurate quantification of these features is critically important in disease diagnosis and the clinical classification of cancer. The system consists of two high NA objective lenses, a light source, a digital spatial light modulator (DMD, by Texas Instrument, an x–y stage, and a CCD detector. The DMD, positioned at the back pupil‐plane of the illumination objective, is employed to illuminate the specimen with parallel rays at any desired angle. The system uses a modification of the convolution backprojection algorithm for reconstruction. In contrast to fluorescent images acquired by a confocal microscope, this instrument produces 3D images of absorption stained material. Microscopic 3D volume reconstructions of absorption‐stained cells have been demonstrated. Reconstructed 3D images of individual cells and tissue can be cut virtually with the distance between the axial slices less than 0.5 μm.

  20. Hepatic Rupture Caused by Hemolysis, Elevated Liver Enzyme, and Low Platelet Count Syndrome: A Case Report with Computed Tomographic and Conventional Angiographic Findings

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Cheong Bok; Ahn, Jae Hong; Choi, Soo Jung; Lee, Jong Hyeog; Park, Man Soo; Jung, Seung Mun; Ryu, Dae Sik [Dept. of Radiology, Asan Foundation, Gangneung Asan Hospital, University of Ulsan College of Medicine, Gangneung (Korea, Republic of)

    2013-03-15

    The authors recently obtained successful clinical outcome after embolization of the hepatic artery and right inferior phrenic artery in a pregnant patient with hemolysis, elevated liver enzyme, and low platelet count (HELLP) syndrome causing hepatic rupture. We report the computed tomographic and conventional angiographic findings in a case of HELLP syndrome, resulting in hepatic infarction and rupture with active bleeding.

  1. Phase-contrast tomographic imaging using an X-ray interferometer

    Energy Technology Data Exchange (ETDEWEB)

    Momose, A. [Hitachi Ltd, Advanced Research Lab., Saitama (Japan); Takeda, T.; Itai, Y. [Univ. of Tsukuba, Inst. of Clinical Medicine, Ibaraki (Japan); Yoneyama, A. [Hitachi Ltd, Central Resarch Lab., Tokyo (Japan); Hirano, K. [High Energy Accelerator Research Organization, Inst. of Materials Structure Science, Ibaraki (Japan)

    1998-05-01

    Apparatus for phase-contrast X-ray computed tomography using a monolithic X-ray interferometer is presented with some observational results for human breast tissues. Structures characteristic of the tissues were revealed in the phase-contrast tomograms. The procedure of image analysis consists of phase retrieval from X-ray interference patterns and tomographic image reconstruction from the retrieved phase shift. Next, feasibility of phase-contrast imaging using a two-crystal X-ray interferometer was studied aiming at in vivo observation in the future. In a preliminary study, the two-crystal X-ray interferometer was capable of generating fringes of 70% visibility using synchrotron X-rays. 35 refs.

  2. Phase-contrast tomographic imaging using an X-ray interferometer

    International Nuclear Information System (INIS)

    Momose, A.; Takeda, T.; Itai, Y.; Yoneyama, A.; Hirano, K.

    1998-01-01

    Apparatus for phase-contrast X-ray computed tomography using a monolithic X-ray interferometer is presented with some observational results for human breast tissues. Structures characteristic of the tissues were revealed in the phase-contrast tomograms. The procedure of image analysis consists of phase retrieval from X-ray interference patterns and tomographic image reconstruction from the retrieved phase shift. Next, feasibility of phase-contrast imaging using a two-crystal X-ray interferometer was studied aiming at in vivo observation in the future. In a preliminary study, the two-crystal X-ray interferometer was capable of generating fringes of 70% visibility using synchrotron X-rays

  3. Rapid tomographic reconstruction based on machine learning for time-resolved combustion diagnostics

    Science.gov (United States)

    Yu, Tao; Cai, Weiwei; Liu, Yingzheng

    2018-04-01

    Optical tomography has attracted surged research efforts recently due to the progress in both the imaging concepts and the sensor and laser technologies. The high spatial and temporal resolutions achievable by these methods provide unprecedented opportunity for diagnosis of complicated turbulent combustion. However, due to the high data throughput and the inefficiency of the prevailing iterative methods, the tomographic reconstructions which are typically conducted off-line are computationally formidable. In this work, we propose an efficient inversion method based on a machine learning algorithm, which can extract useful information from the previous reconstructions and build efficient neural networks to serve as a surrogate model to rapidly predict the reconstructions. Extreme learning machine is cited here as an example for demonstrative purpose simply due to its ease of implementation, fast learning speed, and good generalization performance. Extensive numerical studies were performed, and the results show that the new method can dramatically reduce the computational time compared with the classical iterative methods. This technique is expected to be an alternative to existing methods when sufficient training data are available. Although this work is discussed under the context of tomographic absorption spectroscopy, we expect it to be useful also to other high speed tomographic modalities such as volumetric laser-induced fluorescence and tomographic laser-induced incandescence which have been demonstrated for combustion diagnostics.

  4. Computed tomographic pulmonary angiography in the assessment of severity of chronic thromboembolic pulmonary hypertension and right ventricular dysfunction

    International Nuclear Information System (INIS)

    Liu Min; Ma Zhanhong; Guo Xiaojuan; Zhang Hongxia; Yang Yuanhua; WangChen

    2011-01-01

    Purpose: The aim was to investigate the role of computed tomographic pulmonary angiography (CTPA) in the assessment of severity and right ventricular function in chronic thromboembolic pulmonary hypertension (CTEPH). Materials and methods: Clinical and radiological data of 56 patients with CTEPH January 2006–October 2009 were retrospectively reviewed in the present study. All patients received CTPA with a 64-row CT using the retrospective ECG-Gated mode before digital subtraction pulmonary angiography and right-heart catheterization. CTPA findings including Right Ventricular diameter (RVd) and left ventricular diameter (LVd) were measured at the end diastole. CT Pulmonary Artery Obstruction Indexes including Qanadli Index and Mastora Index were used in the assessment of severity of pulmonary arterial obstruction. Hemodynamic parameters and pulmonary hypertension classification were evaluated by right-heart catheterization in all patients. Right ventricular function was measured with echocardiography in 49 patients. Results: Qanadli Index and Mastora Index respectively were (37.93 ± 14.74)% and (30.92 ± 16.91)%, which showed a significant difference (Z = −5.983, P = 0.000) and a good correlation (r = 0.881, P = 0.000). Neither Qanadli nor Mastora Index correlated with pulmonary hypertension classification (r = −0.009, P = 0.920) or New York Heart Association heart function classification (r = −0.031, P = 0.756). Neither Qanadli nor Mastora Index correlated with any echocardiographic right ventricular parameters (P > 0.05), while RVd/LVd by CTPA correlated with echocardiographic right ventricular functional parameters (P 2 . CTPA findings correlated with hemodynamic variables. Backward linear regression analysis revealed that the RVd/LVd, Right Ventricular Anterior Wall Thickness (RVAWT), Main Pulmonary Artery trunk diameter (MPAd) were shown to be independently associated with mean Pulmonary Artery Pressure (mPAP) levels (model: r 2 = 0.351, P = 0.025; RVd

  5. [Computed tomographic semiotics of respiratory tuberculosis in HIV-infected patients].

    Science.gov (United States)

    Gavrilov, P V; Lazareva, A S; Malashenkov, E A

    2013-01-01

    to study the computed tomographic (CT) semiotics of respiratory tuberculosis in HIV-infected patients in relation to the degree of immunosuppression. The study enrolled 74 patients with verified respiratory tuberculosis in the presence of HIV infection. According to the degree of immunosuppression and the Centers for Disease Control (CDC) and Prevention classification (Atlanta, USA, 1993), the patients were divided into 3 groups: (1) CD4 > or = 500 cells/microl (n = 10); 2) CD4 200-499 cells/microl (n = 28); (3) CD4 <200 cells/microl (n = 36). With spiral CT, focal changes with a predominance of clear-cut foci are visualized at a high frequency in the patients with pulmonary tuberculosis in the presence of HIV infection. In progressive immunosuppression, the CT pattern displays atypical syndromes (frosted glass-type foci, interstitial infiltration, and thin-walled cavities) with the lower rate of alveolar infiltration with confluent foci, as well as lung tissue decay. Enlarged intrathoracic lymph nodes are characteristic of 70.0% of the patients with HIV infection and tuberculosis regardless of the level of CD4 cells. As immunosuppression progresses, the CT pattern of respiratory tuberculosis in the presence of HIV infection shows as atypical syndromes (unclearly defined frosted glass-type focal changes, interstitial infiltrations, and thin-walled cavernous masses). A marked polymorphism in changes and a high rate of lymph node involvement are characteristic.

  6. Mobile 3D tomograph

    International Nuclear Information System (INIS)

    Illerhaus, Bernhard; Goebbels, Juergen; Onel, Yener; Sauerwein, Christoph

    2008-01-01

    Mobile tomographs often have the problem that high spatial resolution is impossible owing to the position or setup of the tomograph. While the tree tomograph developed by Messrs. Isotopenforschung Dr. Sauerwein GmbH worked well in practice, it is no longer used as the spatial resolution and measuring time are insufficient for many modern applications. The paper shows that the mechanical base of the method is sufficient for 3D CT measurements with modern detectors and X-ray tubes. CT measurements with very good statistics take less than 10 min. This means that mobile systems can be used, e.g. in examinations of non-transportable cultural objects or monuments. Enhancement of the spatial resolution of mobile tomographs capable of measuring in any position is made difficult by the fact that the tomograph has moving parts and will therefore have weight shifts. With the aid of tomographies whose spatial resolution is far higher than the mechanical accuracy, a correction method is presented for direct integration of the Feldkamp algorithm [de

  7. Microdose computed tomographic cardiac angiography in normal cats.

    Science.gov (United States)

    Rodriguez, Kiira T; O'Brien, Mauria A; Hartman, Susan K; Mulherin, Allison C; McReynolds, Casie J; McMichael, Maureen; Rapoport, Gregg; O'Brien, Robert T

    2014-03-01

    To determine if microdose contrast-enhanced multi-detector computed tomographic angiography (MDCTA) allows characterization of cardiac chambers in lightly sedated normal cats. Seven healthy domestic cats. Lightly sedated normal cats were imaged pre-contrast and with microdose (0.22 ml/kg of non-ionic iodinated contrast medium, 300 mg I/ml) triple-phase MDCTA in a motion restriction device. On pre-contrast images, the aorta (median: 52.43 Hounsfield units [HU], range 27.35-76.74 HU) was outlined by significantly (p = 0.015) lower attenuating periaortic fat (-66.16 HU, -42.62 to -92.77 HU). On post-contrast images, median peak contrast enhancement in the right ventricle (111.77 HU, 36.09-141.60 HU) was achieved in 3.1 s (range 2.9-7.3 s), in the aorta (149.30 HU, 99.43-319.60 HU) and left atrium (180.83 HU, 88.53-266.84 HU) in 6.4 s (range 5.6-7.7 s) and in the left ventricle (147.89 HU, 57.23-245.77 HU) in 7.10 s (range 6.2-11.2 s). Significantly higher attenuation was measured between all chambers and walls, the right ventricular lumen and interventricular septum (median ratio 53.78 HU, range 0.21-83.20 HU), left ventricular lumen and left ventricular free wall (89.32 HU, 38.81-185.95 HU) and aorta and periaortic fat (190.43 HU, 143.22-425.44 HU) on post-contrast images. Sufficient biological contrast is available on survey CT to discriminate between the aorta and the left atrium, and microdose MDCTA provides sufficient contrast enhancement for adequate visualization of the heart chambers in normal cats. Copyright © 2014 Elsevier B.V. All rights reserved.

  8. Tomographic anthropomorphic models. Pt. 1

    International Nuclear Information System (INIS)

    Veit, R.; Zankl, M.; Petoussi, N.; Mannweiler, E.; Drexler, G.; Williams, G.

    1989-01-01

    The first generation of heterogenoeous anthropomorphic mathematical models to be used in dose calculations was the MIRD-5 adult phantom, followed by the pediatric MIRD-type phantoms and by the GSF sex-specific phantoms ADAM and EVA. A new generation of realistic anthropomorphic models is now introduced. The organs and tissues of these models consist of a well defined number of volume elements (voxels), derived from computer tomographic (CT) data; consequently, these models were named voxel or tomographic models. So far two voxel models of real patients are available: one of an 8 week old baby and of a 7 year old child. For simplicity, the model of the baby will be referred to as BABY and that of the child as CHILD. In chapter 1 a brief literature review is given on the existing mathematical models and their applications. The reasons that lead to the construction of the new CT models is discussed. In chapter 2 the technique is described which allows to convert any physical object into computer files to be used for dose calculations. The technique which produces three dimensional reconstructions of high resolution is discussed. In chapter 3 the main characteristics of the models of the baby and child are given. Tables of organ masses and volumes are presented together with three dimensional images of some organs and tissues. A special mention is given to the assessment of bone marrow distribution. Chapter 4 gives a short description of the Monte Carlo code used in conjunction with the models to calculate organ and tissue doses resulting from photon exposures. Some technical details concerning the computer files which describe the models are also given. (orig./HP)

  9. Gross, computed tomographic and histological findings in mandibular cheek teeth extracted from horses with clinical signs of pulpitis due to apical infection.

    Science.gov (United States)

    Casey, M B; Pearson, G R; Perkins, J D; Tremaine, W H

    2015-09-01

    The most prevalent type of equine dental pulpitis due to apical infection is not associated with coronal fractures or periodontal disease. The pathogenesis of this type of pulpitis is not fully understood. Computed tomography (CT) is increasingly used to investigate equine dental disorders. However, gross, tomographic and histopathological changes in equine dental pulpitis have not been compared previously. To compare gross, CT and histological appearances of sectioned mandibular cheek teeth extracted from horses with clinical signs of pulpitis without coronal fractures or periodontal disease. To contribute to understanding the pathogenesis of equine dental pulpitis. Descriptive study using diseased and healthy teeth. Mandibular cheek teeth extracted from horses with clinical signs of pulpitis (cases), and from cadavers with no history of dental disease (controls), were compared using CT in the transverse plane at 1 mm intervals. Teeth were then sectioned transversely, photographed and processed for histopathological examination. Tomographs were compared with corresponding gross and histological sections. Cement, dentine and bone had similar ranges of attenuation (550-2000 Hounsfield Units, HU) in tomographs but could be differentiated from pulp (-400 to 500 HU) and enamel (> 2500 HU). Twelve discrete dental lesions were identified grossly, 10 of which were characterised histologically. Reactive and reparative dentinogenesis and extensive pulpar mineralisation, previously undescribed, were identified. Pulpar oedema, neutrophilic inflammation, cement and enamel defects, and reactive cemental deposition were also observed. The CT and pathological findings corresponded well where there was mineralised tissue deposited, defects in mineralised tissue, or food material in the pulpar area. Pulpar and dentinal necrosis and cement destruction, evident grossly and histologically, did not correspond to CT changes. Computed tomography is useful for identifying deposition and

  10. Computed microtomography and X-ray fluorescence analysis for comprehensive analysis of structural changes in bone.

    Science.gov (United States)

    Buzmakov, Alexey; Chukalina, Marina; Nikolaev, Dmitry; Schaefer, Gerald; Gulimova, Victoria; Saveliev, Sergey; Tereschenko, Elena; Seregin, Alexey; Senin, Roman; Prun, Victor; Zolotov, Denis; Asadchikov, Victor

    2013-01-01

    This paper presents the results of a comprehensive analysis of structural changes in the caudal vertebrae of Turner's thick-toed geckos by computer microtomography and X-ray fluorescence analysis. We present algorithms used for the reconstruction of tomographic images which allow to work with high noise level projections that represent typical conditions dictated by the nature of the samples. Reptiles, due to their ruggedness, small size, belonging to the amniote and a number of other valuable features, are an attractive model object for long-orbital experiments on unmanned spacecraft. Issues of possible changes in their bone tissue under the influence of spaceflight are the subject of discussions between biologists from different laboratories around the world.

  11. A distributed multi-GPU system for high speed electron microscopic tomographic reconstruction.

    Science.gov (United States)

    Zheng, Shawn Q; Branlund, Eric; Kesthelyi, Bettina; Braunfeld, Michael B; Cheng, Yifan; Sedat, John W; Agard, David A

    2011-07-01

    Full resolution electron microscopic tomographic (EMT) reconstruction of large-scale tilt series requires significant computing power. The desire to perform multiple cycles of iterative reconstruction and realignment dramatically increases the pressing need to improve reconstruction performance. This has motivated us to develop a distributed multi-GPU (graphics processing unit) system to provide the required computing power for rapid constrained, iterative reconstructions of very large three-dimensional (3D) volumes. The participating GPUs reconstruct segments of the volume in parallel, and subsequently, the segments are assembled to form the complete 3D volume. Owing to its power and versatility, the CUDA (NVIDIA, USA) platform was selected for GPU implementation of the EMT reconstruction. For a system containing 10 GPUs provided by 5 GTX295 cards, 10 cycles of SIRT reconstruction for a tomogram of 4096(2) × 512 voxels from an input tilt series containing 122 projection images of 4096(2) pixels (single precision float) takes a total of 1845 s of which 1032 s are for computation with the remainder being the system overhead. The same system takes only 39 s total to reconstruct 1024(2) × 256 voxels from 122 1024(2) pixel projections. While the system overhead is non-trivial, performance analysis indicates that adding extra GPUs to the system would lead to steadily enhanced overall performance. Therefore, this system can be easily expanded to generate superior computing power for very large tomographic reconstructions and especially to empower iterative cycles of reconstruction and realignment. Copyright © 2011 Elsevier B.V. All rights reserved.

  12. Computed tomographic features of apical infection of equine maxillary cheek teeth: a retrospective study of 49 horses.

    Science.gov (United States)

    Bühler, M; Fürst, A; Lewis, F I; Kummer, M; Ohlerth, S

    2014-07-01

    Computed tomographic (CT) studies evaluating the relevance of individual CT features of apical infection in maxillary cheek teeth are lacking. To study the prevalence and relationship of single CT features in horses with and without clinical evidence of apical infection in maxillary cheek teeth. Retrospective case-control study. Multislice CT scans of the head of 49 horses were evaluated retrospectively. Changes of the infundibulum, pulp, root, lamina dura, periodontal space and alveolar bone in maxillary cheek teeth were recorded. Single CT changes were much more prevalent in the 28 horses with clinical signs. However, infundibular changes and a nondetectable lamina dura were also common in the 21 horses without clinical evidence of apical infection. Computed tomographic abnormalities of the pulp, root, periapical bone and periodontal space and the presence of a tooth fracture were significantly related. Infundibular changes were not associated with other CT signs of apical infection. Although nondetectable lamina dura was the most frequent CT change in all teeth in both studied groups, it was most commonly a solitary feature in otherwise normal teeth. Apical infections, defined as ≥3 CT changes, occurred mainly in the 108/208, 109/209 and 110/210 (Triadan numbers) and were found only in horses with clinical evidence of apical infection, except in one horse without clinical signs that had one affected root. Combined CT changes of the pulp, root, lamina dura, periapical bone and periodontal space and the presence of a tooth fracture appear to be reliable features to diagnose apical infection in maxillary cheek teeth. As a solitary feature, a nondetectable lamina dura should be interpreted cautiously and may even be considered normal due to its minor thickness and/or too low resolution of the imaging modality. © 2013 EVJ Ltd.

  13. Quantification of wall motion and phase of contraction in tomographic gated blood pool studies using length-based Fourier analysis

    Energy Technology Data Exchange (ETDEWEB)

    Nakajima, Kenichi; Bunko, Hisashi; Taki, Junichi; Nambu, Ichiro; Shiire, Yasushi; Tonami, Norihisa; Hisada, Kinichi; Tada, Akira; Kojima, Kazuhkio

    1985-03-01

    Length-based Fourier analysis, a new method for quantification of wall motion and timing of contraction, was applied to tomographic gated blood pool study. Two parameters, percent-length shortening (%LS) and length-based phase were calculated based on the time-length curves from a center to ventricular edges, and compared with the count-based method. In mathematical models for tomographic gated blood pool images, the severity of asynergy was easily determined by length-based method, and the accuracy of the parameters was good. As to the setting of the center, fixed center provided more reliable parameters than the method using movable center, i.e., when a center of gravity was determined in each frame. By length-based Fourier analysis, quantification of wall motion was easily performed, and the initial inward movement caused by the accessory conduction pathway was assessed in patients with Wolff-Parkinson-White syndrome. Length-based approach was considered to be reasonable and effective because the movements of the ventricular edges are essential in tomographic gated blood pool images.

  14. Quantification of wall motion and phase of contraction in tomographic gated blood pool studies using length-based Fourier analysis

    International Nuclear Information System (INIS)

    Nakajima, Kenichi; Bunko, Hisashi; Taki, Junichi; Nambu, Ichiro; Shiire, Yasushi; Tonami, Norihisa; Hisada, Kinichi; Tada, Akira; Kojima, Kazuhiko.

    1985-01-01

    Length-based Fourier analysis, a new method for quantification of wall motion and timing of contraction, was applied to tomographic gated blood pool study. Two parameters, percent-length shortening (%LS) and length-based phase were calculated based on the time-length curves from a center to ventricular edges, and compared with the count-based method. In mathematical models for tomographic gated blood pool images, the severity of asynergy was easily determined by length-based method, and the accuracy of the parameters was good. As to the setting of the center, fixed center provided more reliable parameters than the method using movable center, i.e., when a center of gravity was determined in each frame. By length-based Fourier analysis, quantification of wall motion was easily performed, and the initial inward movement caused by the accessory conduction pathway was assessed in patients with Wolff-Parkinson-White syndrome. Length-based approach was considered to be reasonable and effective because the movements of the ventricular edges are essential in tomographic gated blood pool images. (author)

  15. Clinical perspective of coronary computed tomographic angiography in diagnosis of coronary artery disease

    International Nuclear Information System (INIS)

    Chang, Hyuk-Jae; Chung, Namsik

    2011-01-01

    Since a 4-detector row coronary computed tomographic angiography (CCTA) was launched in 1998, CCTA has experienced rapid improvement of imaging qualities with the ongoing evolution of computed tomography (CT) technology. The diagnostic accuracy of CCTA to detect coronary artery stenosis is well established, whereas improvements are still needed to reduce the overestimation of coronary artery disease (CAD) and assess plaque composition. CCTA has been used to evaluate CAD in various clinical settings. For example, CCTA could be an efficient initial triage tool at emergency departments for patients with acute chest pain with low-to-intermediate risk because of its high negative predictive value. In patients with suspected CAD, CCTA could be a cost-effective alternative to myocardial perfusion imaging and exercise electrocardiogram for the initial coronary evaluation of patients with intermediate pre-test likelihood suspected CAD. However, in asymptomatic populations, there is a lack of studies that show an improved prognostic power of CCTA over other modalities. Therefore, the clinical use of CCTA to detect CAD for purposes of risk stratification in asymptomatic individuals should be discouraged. As CT technology evolves, CCTA will provide better quality coronary imaging and non-coronary information with lower radiation exposure. Future studies should cover these ongoing technical improvements and evaluate the prognostic power of CCTA in various clinical settings of CAD in large, well-designed, randomized trials. (author)

  16. Registration of synthetic tomographic projection data sets using cross-correlation

    International Nuclear Information System (INIS)

    Fitchard, E.E.; Aldridge, J.S.; Reckwerdt, P.J.; Mackie, T.R.

    1998-01-01

    Tomographic registration, a method that makes possible accurate patient registration directly from projection data, consists of three processing steps: (i) manual coarse positioning, (ii) tomographic projection set acquisition, and (iii) computer mediated refined positioning. In the coarse positioning stage, the degree of patient alignment is comparable with that achieved with the standard radiotherapy set-up. However, the accuracy requirements are somewhat more relaxed in that meticulous alignment of the patient using external laser indicators is not necessary. Instead, tomographic projection sets are compared with planning CTs in order to achieve improved patient set-up. The projection sets are cross-correlated to obtain the best-fit translation and rotation offsets. The algorithm has been tested on synthetic data with the incorporation of varying amounts of Gaussian pseudo-random noise. These tests demonstrate the algorithm's stability and also confirm that alignment can be achieved with an accuracy of less than one projection pixel. (author)

  17. Estimation of spatial uncertainties of tomographic velocity models

    Energy Technology Data Exchange (ETDEWEB)

    Jordan, M.; Du, Z.; Querendez, E. [SINTEF Petroleum Research, Trondheim (Norway)

    2012-12-15

    This research project aims to evaluate the possibility of assessing the spatial uncertainties in tomographic velocity model building in a quantitative way. The project is intended to serve as a test of whether accurate and specific uncertainty estimates (e.g., in meters) can be obtained. The project is based on Monte Carlo-type perturbations of the velocity model as obtained from the tomographic inversion guided by diagonal and off-diagonal elements of the resolution and the covariance matrices. The implementation and testing of this method was based on the SINTEF in-house stereotomography code, using small synthetic 2D data sets. To test the method the calculation and output of the covariance and resolution matrices was implemented, and software to perform the error estimation was created. The work included the creation of 2D synthetic data sets, the implementation and testing of the software to conduct the tests (output of the covariance and resolution matrices which are not implicitly provided by stereotomography), application to synthetic data sets, analysis of the test results, and creating the final report. The results show that this method can be used to estimate the spatial errors in tomographic images quantitatively. The results agree with' the known errors for our synthetic models. However, the method can only be applied to structures in the model, where the change of seismic velocity is larger than the predicted error of the velocity parameter amplitudes. In addition, the analysis is dependent on the tomographic method, e.g., regularization and parameterization. The conducted tests were very successful and we believe that this method could be developed further to be applied to third party tomographic images.

  18. Motion tracking-enhanced MART for tomographic PIV

    International Nuclear Information System (INIS)

    Novara, Matteo; Scarano, Fulvio; Batenburg, Kees Joost

    2010-01-01

    A novel technique to increase the accuracy of multiplicative algebraic reconstruction technique (MART) reconstruction from tomographic particle image velocimetry (PIV) recordings at higher seeding density than currently possible is presented. The motion tracking enhancement (MTE) method is based on the combined utilization of images from two or more exposures to enhance the reconstruction of individual intensity fields. The working principle is first introduced qualitatively, and the mathematical background is given that explains how the MART reconstruction can be improved on the basis of an improved first guess object obtained from the combination of non-simultaneous views reduced to the same time instant deforming the 3D objects by an estimate of the particle motion field. The performances of MTE are quantitatively evaluated by numerical simulation of the imaging, reconstruction and image correlation processes. The cases of two or more exposures obtained from time-resolved experiments are considered. The iterative application of MTE appears to significantly improve the reconstruction quality, first by decreasing the intensity of the ghost images and second, by increasing the intensity and the reconstruction precision for the actual particles. Based on computer simulations, the maximum imaged seeding density that can be dealt with is tripled with respect to the MART analysis applied to a single exposure. The analysis also illustrates that the maximum effect of the MTE method is comparable to that of doubling the number of cameras in the tomographic system. Experiments performed on a transitional jet at Re = 5000 apply the MTE method to double-frame recordings. The velocity measurement precision is increased for a system with fewer views (two or three cameras compared with four cameras). The ghost particles' intensity is also visibly reduced although to a lesser extent with respect to the computer simulations. The velocity and vorticity field obtained from a three

  19. Comparative evaluation of the cadaveric and computed tomographic features of the coelomic cavity in the green iguana (Iguana iguana), black and white tegu (Tupinambis merianae) and bearded dragon (Pogona vitticeps).

    Science.gov (United States)

    Banzato, T; Selleri, P; Veladiano, I A; Zotti, A

    2013-12-01

    Contrast-enhanced computed tomographic studies of the coelomic cavity in four green iguanas, four black and white tegus and four bearded dragons were performed using a conventional CT scanner. Anatomical reference cross sections were obtained from four green iguana, four black and white tegu and six bearded dragon cadavers; the specimens were stored in a -20°C freezer for 24 h then sliced into 5-mm intervals. The frozen sections were cleaned with water and photographed on both sides. The individual anatomical structures were identified by means of the available literature; these were labelled first on the anatomical images and then matched to the corresponding computed tomography images. The results provide an atlas of the normal cross-sectional and computed tomographic anatomy of the coelomic cavity in the green iguana, the black and white tegu and the bearded dragon, which is useful in the interpretation of any imaging modality. © 2013 Blackwell Verlag GmbH.

  20. Results of computer-tomographic examination in different forms and course of schizophrenia

    International Nuclear Information System (INIS)

    Stojchev, R.

    1991-01-01

    Data are reported of a clinical and computer-tomographic study of 103 schizophrenic patients. Those with simple form of the disease had most pronounced evidence of dilated III and lateral ventricles (41.8% of the cases for the III ventricle and 72.4% for the lateral ventricles). All patients with circular, simple and catatonic form had signs of pathology of the cortical sulci. Regarding the ventricular system evidences of pathology prevailed in cases of impetus-progredient and constantly progredient course, whereas in respect to cortical pathology, the results were almost identical in all three types of psychosis - 95.2% of cases of constantly progredient and 95.6% - of impetus-progredient course. Attention was called to the 'surprising' data of organic brain injury in patients with paranoid and circular form of the disease, as well as in the most benign (from clinical point of view) impetus course. It is assumed that morphologic changes in the brain of schizophrenic patients are a natural phenomenon, but so far have not been a subject of comprehensive studies, maybe because of prejudice or lack of appropriate methods for examination of the brain during life's time. 6 figs., 15 refs

  1. Tomographic Image Reconstruction Using Training Images with Matrix and Tensor Formulations

    DEFF Research Database (Denmark)

    Soltani, Sara

    the image resolution compared to a classical reconstruction method such as Filtered Back Projection (FBP). Some priors for the tomographic reconstruction take the form of cross-section images of similar objects, providing a set of the so-called training images, that hold the key to the structural......Reducing X-ray exposure while maintaining the image quality is a major challenge in computed tomography (CT); since the imperfect data produced from the few view and/or low intensity projections results in low-quality images that are suffering from severe artifacts when using conventional...... information about the solution. The training images must be reliable and application-specific. This PhD project aims at providing a mathematical and computational framework for the use of training sets as non-parametric priors for the solution in tomographic image reconstruction. Through an unsupervised...

  2. Reproducibility of temporomandibular joint tomography. Influence of shifted X-ray beam and tomographic focal plane on reproducibility

    International Nuclear Information System (INIS)

    Saito, Masashi

    1999-01-01

    Proper tomographic focal plane and x-ray beam direction are the most important factors to obtain accurate images of the temporomandibular joint (TMJ). In this study, to clarify the magnitude of effect of these two factors on the image quality. We evaluated the reproducibility of tomograms by measuring the distortion when the x-ray beam was shifted from the correct center of the object. The effects of the deviation of the tomographic focal plane on image quality were evaluated by the MTF (Modulation Transfer Function). Two types of tomograms, one the plane type, the other the rotational type were used in this study. A TMJ model was made from Teflon for the purpose of evaluation by shifting the x-ray beam. The x-ray images were obtained by tilting the model from 0 to 10 degrees 2-degree increments. These x-ray images were processed for computer image analysis, and then the distance between condyle and the joint space was measured. To evaluate the influence of the shifted tomographic focal plane on image sharpness, the x-ray images from each setting were analyzed by MTF. To obtain the MTF, ''knife-edge'' made from Pb was used. The images were scanned with a microdensitometer at the central focal plane, and 0, 0.5, 1 mm away respectively. The density curves were analyzed by Fourier analysis and the MTF was calculated. The reproducibility of images became worse by shifting the x-ray beam. This tendency was similar for both tomograms. Object characteristics such as anterior and posterior portion of the joint space affected the deterioration of reproducibility of the tomography. The deviation of the tomographic focal plane also decreased the reproducibility of the x-ray images. The rotational type showed a better MTF, but it became seriously unfavorable with slight changes of the tomographic focal plane. Contrarily, the plane type showed a lower MTF, but the image was stable with shifting of the tomographic focal plane. (author)

  3. Computed tomographic pelvimetry in English bulldogs.

    Science.gov (United States)

    Dobak, Tetyda P; Voorhout, George; Vernooij, Johannes C M; Boroffka, Susanne A E B

    2018-05-31

    English bulldogs have been reported to have a high incidence of dystocia and caesarean section is often performed electively in this breed. A narrow pelvic canal is the major maternal factor contributing to obstructive dystocia. The objective of this cross-sectional study was to assess the pelvic dimensions of 40 clinically healthy English bulldogs using computed tomography pelvimetry. A control group consisting of 30 non-brachycephalic dogs that underwent pelvic computed tomography was retrospectively collected from the patient archive system. Univariate analysis of variance was used to compare computed tomography pelvimetry of both groups and the effects of weight and gender on the measurements. In addition, ratios were obtained to address pelvic shape differences. A significantly (P = 0.00) smaller pelvic size was found in English bulldogs compared to the control group for all computed tomography measurements: width and length of the pelvis, pelvic inlet and caudal pelvic aperture. The pelvic conformation was significantly different between the groups, English bulldogs had an overall shorter pelvis and pelvic canal and a narrower pelvic outlet. Weight had a significant effect on all measurements whereas gender that only had a significant effect on some (4/11) pelvic dimensions. Our findings prove that English bulldogs have a generally reduced pelvic size as well as a shorter pelvis and narrower pelvic outlet when compared to non-brachycephalic breeds. We suggest that some of our measurements may serve as a baseline for pelvic dimensions in English bulldogs and may be useful for future studies on dystocia in this breed. Copyright © 2018 Elsevier Inc. All rights reserved.

  4. Advances in tomographic PIV

    NARCIS (Netherlands)

    Novara, M.

    2013-01-01

    This research deals with advanced developments in 3D particle image velocimetry based on the tomographic PIV technique (Tomo-PIV). The latter is a relatively recent measurement technique introduced by Elsinga et al. in 2005, which is based on the tomographic reconstruction of particle tracers in

  5. Computed tomography of the sacrum: 1. normal anatomy

    International Nuclear Information System (INIS)

    Whelan, M.A.; Gold, R.P.

    1982-01-01

    The sacrum of a disarticulated pelvis was scanned with a Pfizer 0450 computed tomographic scanner using contiguous 5 mm sections to display the normal computed tomographic anatomy of the sacrum. These anatomic sections were then compared with normal sacrums. In analyzing the computed tomographic anatomy, emphasis was placed on the central canal and sacral foramina, in that these landmarks are important in determining not only the presence but also the type of pathology involving the sacrum

  6. A distributed multi-GPU system for high speed electron microscopic tomographic reconstruction

    Energy Technology Data Exchange (ETDEWEB)

    Zheng, Shawn Q.; Branlund, Eric; Kesthelyi, Bettina; Braunfeld, Michael B.; Cheng, Yifan; Sedat, John W. [The Howard Hughes Medical Institute and the W.M. Keck Advanced Microscopy Laboratory, Department of Biochemistry and Biophysics, University of California, San Francisco, 600, 16th Street, Room S412D, CA 94158-2517 (United States); Agard, David A., E-mail: agard@msg.ucsf.edu [The Howard Hughes Medical Institute and the W.M. Keck Advanced Microscopy Laboratory, Department of Biochemistry and Biophysics, University of California, San Francisco, 600, 16th Street, Room S412D, CA 94158-2517 (United States)

    2011-07-15

    Full resolution electron microscopic tomographic (EMT) reconstruction of large-scale tilt series requires significant computing power. The desire to perform multiple cycles of iterative reconstruction and realignment dramatically increases the pressing need to improve reconstruction performance. This has motivated us to develop a distributed multi-GPU (graphics processing unit) system to provide the required computing power for rapid constrained, iterative reconstructions of very large three-dimensional (3D) volumes. The participating GPUs reconstruct segments of the volume in parallel, and subsequently, the segments are assembled to form the complete 3D volume. Owing to its power and versatility, the CUDA (NVIDIA, USA) platform was selected for GPU implementation of the EMT reconstruction. For a system containing 10 GPUs provided by 5 GTX295 cards, 10 cycles of SIRT reconstruction for a tomogram of 4096{sup 2}x512 voxels from an input tilt series containing 122 projection images of 4096{sup 2} pixels (single precision float) takes a total of 1845 s of which 1032 s are for computation with the remainder being the system overhead. The same system takes only 39 s total to reconstruct 1024{sup 2}x256 voxels from 122 1024{sup 2} pixel projections. While the system overhead is non-trivial, performance analysis indicates that adding extra GPUs to the system would lead to steadily enhanced overall performance. Therefore, this system can be easily expanded to generate superior computing power for very large tomographic reconstructions and especially to empower iterative cycles of reconstruction and realignment. -- Highlights: {yields} A distributed multi-GPU system has been developed for electron microscopic tomography (EMT). {yields} This system allows for rapid constrained, iterative reconstruction of very large volumes. {yields} This system can be easily expanded to generate superior computing power for large-scale iterative EMT realignment.

  7. A distributed multi-GPU system for high speed electron microscopic tomographic reconstruction

    International Nuclear Information System (INIS)

    Zheng, Shawn Q.; Branlund, Eric; Kesthelyi, Bettina; Braunfeld, Michael B.; Cheng, Yifan; Sedat, John W.; Agard, David A.

    2011-01-01

    Full resolution electron microscopic tomographic (EMT) reconstruction of large-scale tilt series requires significant computing power. The desire to perform multiple cycles of iterative reconstruction and realignment dramatically increases the pressing need to improve reconstruction performance. This has motivated us to develop a distributed multi-GPU (graphics processing unit) system to provide the required computing power for rapid constrained, iterative reconstructions of very large three-dimensional (3D) volumes. The participating GPUs reconstruct segments of the volume in parallel, and subsequently, the segments are assembled to form the complete 3D volume. Owing to its power and versatility, the CUDA (NVIDIA, USA) platform was selected for GPU implementation of the EMT reconstruction. For a system containing 10 GPUs provided by 5 GTX295 cards, 10 cycles of SIRT reconstruction for a tomogram of 4096 2 x512 voxels from an input tilt series containing 122 projection images of 4096 2 pixels (single precision float) takes a total of 1845 s of which 1032 s are for computation with the remainder being the system overhead. The same system takes only 39 s total to reconstruct 1024 2 x256 voxels from 122 1024 2 pixel projections. While the system overhead is non-trivial, performance analysis indicates that adding extra GPUs to the system would lead to steadily enhanced overall performance. Therefore, this system can be easily expanded to generate superior computing power for very large tomographic reconstructions and especially to empower iterative cycles of reconstruction and realignment. -- Highlights: → A distributed multi-GPU system has been developed for electron microscopic tomography (EMT). → This system allows for rapid constrained, iterative reconstruction of very large volumes. → This system can be easily expanded to generate superior computing power for large-scale iterative EMT realignment.

  8. Evaluation of computed tomographic and radiographic myelography in normal miniature pigs

    International Nuclear Information System (INIS)

    Choi, M.H.; Lee, H.Y.; Kim, M.E.; Kim, J.Y.; Lee, N.S.; Chang, J.H.; Jung, J.H.; Choi, M.C.

    2010-01-01

    Evaluation of the myelography was studied in miniature pigs. Radiographs and computed tomographic (CT) images of the whole spine were obtained at clinically healthy twelve miniature pigs of 4 (8.7-10 kg) and 12 (26-31 kg) months. The assessments of the spinal cord were made in accordance with the Pavlov's method and compared area ratio [at spinal cord (SC), vertebral canal (VC) and vertebral body (VB)]. The Pavlov's ratio in the cervical spine was significant larger than that of thoracolumbar in radiographic myelography. On CT myelography, the area of the spinal cord had a significant difference between the cervical and thoracolumbar spine. Among the cervical spine, the ratios of spinal cord and vertebral body (SC : VB), vertebral canal and vertebral body (VC : VB) were minimum at the level of 4th cervical spine in both ages, while maximum at the level of 6th cervical spine in both months. In case of lumbar spine, the ratios of spinal cord and vertebral body (SC : VB) were the largest at the level of 4th lumbar spine in 4 months and at the level of 3rd lumbar spine in 12 months. In addition, the ratio of spinal cord and vertebral body (SC : VB) of the cervical spinal cord was significant lower at 4 months but the lumbar spinal cord showed lower pattern at 12 months old miniature pigs

  9. Soil structure characterized using computed tomographic images

    Science.gov (United States)

    Zhanqi Cheng; Stephen H. Anderson; Clark J. Gantzer; J. W. Van Sambeek

    2003-01-01

    Fractal analysis of soil structure is a relatively new method for quantifying the effects of management systems on soil properties and quality. The objective of this work was to explore several methods of studying images to describe and quantify structure of soils under forest management. This research uses computed tomography and a topological method called Multiple...

  10. Application of tomographic techniques to two-dimensional surface analysis using the Harwell nuclear microprobe

    International Nuclear Information System (INIS)

    Huddleston, J.; Hutchinson, I.G.; Pierce, T.B.

    1983-01-01

    Nuclear methods of surface analysis are discussed briefly, and the circumstances are described in which a two-dimensional analysis of the sample surface is desirable to enable the surface composition to be mapped accurately. Tomographic techniques of data manipulation are outlined. Data acquisition in the present case is performed by moving the sample in a defined sequence of positions, at each of which analytical data are gathered by the proton microprobe. The method and equipment are outlined. Data processing leading to the reconstruction of the image is summarised. (U.K.)

  11. Comparative evaluation of the cadaveric, radiographic and computed tomographic anatomy of the heads of green iguana (Iguana iguana), common tegu (Tupinambis merianae) and bearded dragon (Pogona vitticeps).

    Science.gov (United States)

    Banzato, Tommaso; Selleri, Paolo; Veladiano, Irene A; Martin, Andrea; Zanetti, Emanuele; Zotti, Alessandro

    2012-05-11

    Radiology and computed tomography are the most commonly available diagnostic tools for the diagnosis of pathologies affecting the head and skull in veterinary practice. Nevertheless, accurate interpretation of radiographic and CT studies requires a thorough knowledge of the gross and the cross-sectional anatomy. Despite the increasing success of reptiles as pets, only a few reports over their normal imaging features are currently available. The aim of this study is to describe the normal cadaveric, radiographic and computed tomographic features of the heads of the green iguana, tegu and bearded dragon. 6 adult green iguanas, 4 tegus, 3 bearded dragons, and, the adult cadavers of: 4 green iguana, 4 tegu, 4 bearded dragon were included in the study. 2 cadavers were dissected following a stratigraphic approach and 2 cadavers were cross-sectioned for each species. These latter specimens were stored in a freezer (-20°C) until completely frozen. Transversal sections at 5 mm intervals were obtained by means of an electric band-saw. Each section was cleaned and photographed on both sides. Radiographs of the head of each subject were obtained. Pre- and post- contrast computed tomographic studies of the head were performed on all the live animals. CT images were displayed in both bone and soft tissue windows. Individual anatomic structures were first recognised and labelled on the anatomic images and then matched on radiographs and CT images. Radiographic and CT images of the skull provided good detail of the bony structures in all species. In CT contrast medium injection enabled good detail of the soft tissues to be obtained in the iguana whereas only the eye was clearly distinguishable from the remaining soft tissues in both the tegu and the bearded dragon. The results provide an atlas of the normal anatomical and in vivo radiographic and computed tomographic features of the heads of lizards, and this may be useful in interpreting any imaging modality involving these

  12. Comparative evaluation of the cadaveric, radiographic and computed tomographic anatomy of the heads of green iguana (Iguana iguana) , common tegu ( Tupinambis merianae) and bearded dragon ( Pogona vitticeps)

    Science.gov (United States)

    2012-01-01

    Background Radiology and computed tomography are the most commonly available diagnostic tools for the diagnosis of pathologies affecting the head and skull in veterinary practice. Nevertheless, accurate interpretation of radiographic and CT studies requires a thorough knowledge of the gross and the cross-sectional anatomy. Despite the increasing success of reptiles as pets, only a few reports over their normal imaging features are currently available. The aim of this study is to describe the normal cadaveric, radiographic and computed tomographic features of the heads of the green iguana, tegu and bearded dragon. Results 6 adult green iguanas, 4 tegus, 3 bearded dragons, and, the adult cadavers of : 4 green iguana, 4 tegu, 4 bearded dragon were included in the study. 2 cadavers were dissected following a stratigraphic approach and 2 cadavers were cross-sectioned for each species. These latter specimens were stored in a freezer (−20°C) until completely frozen. Transversal sections at 5 mm intervals were obtained by means of an electric band-saw. Each section was cleaned and photographed on both sides. Radiographs of the head of each subject were obtained. Pre- and post- contrast computed tomographic studies of the head were performed on all the live animals. CT images were displayed in both bone and soft tissue windows. Individual anatomic structures were first recognised and labelled on the anatomic images and then matched on radiographs and CT images. Radiographic and CT images of the skull provided good detail of the bony structures in all species. In CT contrast medium injection enabled good detail of the soft tissues to be obtained in the iguana whereas only the eye was clearly distinguishable from the remaining soft tissues in both the tegu and the bearded dragon. Conclusions The results provide an atlas of the normal anatomical and in vivo radiographic and computed tomographic features of the heads of lizards, and this may be useful in interpreting any

  13. Comparative evaluation of the cadaveric, radiographic and computed tomographic anatomy of the heads of green iguana (Iguana iguana , common tegu ( Tupinambis merianae and bearded dragon ( Pogona vitticeps

    Directory of Open Access Journals (Sweden)

    Banzato Tommaso

    2012-05-01

    Full Text Available Abstract Background Radiology and computed tomography are the most commonly available diagnostic tools for the diagnosis of pathologies affecting the head and skull in veterinary practice. Nevertheless, accurate interpretation of radiographic and CT studies requires a thorough knowledge of the gross and the cross-sectional anatomy. Despite the increasing success of reptiles as pets, only a few reports over their normal imaging features are currently available. The aim of this study is to describe the normal cadaveric, radiographic and computed tomographic features of the heads of the green iguana, tegu and bearded dragon. Results 6 adult green iguanas, 4 tegus, 3 bearded dragons, and, the adult cadavers of : 4 green iguana, 4 tegu, 4 bearded dragon were included in the study. 2 cadavers were dissected following a stratigraphic approach and 2 cadavers were cross-sectioned for each species. These latter specimens were stored in a freezer (−20°C until completely frozen. Transversal sections at 5 mm intervals were obtained by means of an electric band-saw. Each section was cleaned and photographed on both sides. Radiographs of the head of each subject were obtained. Pre- and post- contrast computed tomographic studies of the head were performed on all the live animals. CT images were displayed in both bone and soft tissue windows. Individual anatomic structures were first recognised and labelled on the anatomic images and then matched on radiographs and CT images. Radiographic and CT images of the skull provided good detail of the bony structures in all species. In CT contrast medium injection enabled good detail of the soft tissues to be obtained in the iguana whereas only the eye was clearly distinguishable from the remaining soft tissues in both the tegu and the bearded dragon. Conclusions The results provide an atlas of the normal anatomical and in vivo radiographic and computed tomographic features of the heads of lizards, and this may be

  14. Computed tomographic colonography (CTC) performance: one-year clinical follow-up

    International Nuclear Information System (INIS)

    Duff, S.E.; Murray, D.; Rate, A.J.; Richards, D.M.; Kumar, N.A. Mahesh

    2006-01-01

    Aim: Computed tomographic colonography (CTC) represents a valuable advance in imaging technology for patients with colonic symptoms who are unfit for or fail to complete investigation with conventional techniques of colonoscopy or barium enema. The aim of this study was to examine whether CTC was sufficient to exclude colorectal cancer in such a population. As our patients were unfit for or unable to complete conventional investigations, we used 1 year clinical follow-up to exclude colonic malignancy. Materials and Methods: CTC examination was performed using multi-slice CT in patients fitting pre-determined criteria. All patients who had completed 12 months of follow-up after CTC were included. Data were extracted from patient records and lack of presentation within the 12 months following a negative CTC was assumed to equate to lack of colorectal cancer at initial investigation. Results: One hundred and twelve patients underwent CTC with a median age of 78 years (range 39-95) and median follow-up of 18 months (range 12-26). CTC detected 7 colorectal cancers, with 3 false positives and 1 false negative, giving a sensitivity of 87.5% and specificity of 97.1% for the detection of colorectal cancer. Conclusions: CTC is a good imaging tool for the exclusion of colorectal cancer in a population unfit for or unable to complete colonoscopy or barium enema, with reasonable sensitivity and specificity for detection of colorectal cancer. However, the optimum investigative strategy for fitter symptomatic individuals is still debated and should be clarified by the results of ongoing randomised controlled trials

  15. Regrowth patterns of supratentorial gliomas: estimation from computed tomographic scans

    International Nuclear Information System (INIS)

    Tsuboi, K.; Yoshii, Y.; Nakagawa, K.; Maki, Y.

    1986-01-01

    To clarify the regrowth patterns of benign and malignant gliomas, we chose 27 intervals (between two operations or between an operation and autopsy) from 21 patients with pathologically verified recurrent supratentorial gliomas. Serial computed tomographic (CT) scans of these cases were analyzed to determine the doubling time (Td) calculated from the change in volume of enhanced and low density areas, the enhancement effect graded from 0 to 4 according to the Hounsfield number, and the presence of dissemination and contralateral extension. We studied 5 benign gliomas (including 1 case of radiation necrosis), 8 malignant astrocytomas, and 8 glioblastomas. The Td's of enhanced areas on CT scans of benign gliomas, malignant astrocytomas, and glioblastomas were 937 +/- 66.5 days, 65.1 +/- 29.4 days, and 48.1 +/- 20.9 days, respectively. The Td's of low density areas were 895 +/- 130.6 days, 70.8 +/- 22.2 days, and 50.5 +/- 14.7 days. There was a significant correlation between the Td's of the enhanced and low density areas (0.97). The enhancement effect increased at recurrence in 55% of the cases, with an average increase of 1.1 grades. The increase in enhancement effect at recurrence showed a tendency to become smaller as the tumor's degree of anaplasia increased. Radiotherapy was effective in significantly retarding the growth rate of malignant gliomas, whose Td's were doubled. Although the Td's of both enhanced and low density areas of benign gliomas were significantly longer than those of malignant gliomas, there was no significant difference in the Td's of enhanced areas between malignant astrocytomas and glioblastomas

  16. Orthopedic applications of single photon emission computed Tomographic bone scanning

    International Nuclear Information System (INIS)

    Collier, B.D.

    1987-01-01

    When compared with planar bone scanning, single photon emission computed tomography (SPECT) has technical advantages of potential diagnostic significance. Planar imaging often superimposes substantial underlying or overlying activity on the bony structure of medical interest. SPECT, however, can be used to remove such unwanted activity. For example, in the hip the acetabulum extends downwards behind the femoral head. Therefore when using planar bone scanning techniques, the photon-deficient defect typical of avascular necrosis (AVN) of the femoral had may be obscured by activity originating in the underlying acetabulum. By using SPECT, underlying and overlying distributions of activity can be separated into sequential tomographic planes. For this reason SPECT facilitates the detection of AVN of the femoral head. When referring a patient without a history of malignancy for bone scanning, the orthopaedic surgeon usually has a specific clinical question involving a limited portion of the skeleton. Orthopaedic surgeons at their institution commonly use bone scanning to clarify the cause of back, hip or knee pain; to determine with a physiological test the significance of radiographic findings; and to establish the extent of disease at symptomatic skeletal sites such as the three compartments of the knee. In instances such as these, when clinical concern is limited to a specific anatomical region, a bone scan procedure that includes SPECT imaging of only a portion of the skeleton is appropriate. To date, SPECT of the skeletal system has most frequently been used to evaluate patients with pain the larger joints and bony structures such as the lumbar spine, hips, knees, or temporomandibular joints (TMJ)

  17. Computed tomographic features of lymphangioleiomyomatosis: Evaluation in 138 patients

    Energy Technology Data Exchange (ETDEWEB)

    Tobino, Kazunori, E-mail: tobino@juntendo.ac.jp [Department of Respiratory Medicine, Iizuka Hospital, 3-83 Yoshiomachi, Iizuka, Fukuoka 820-0018 (Japan); Division of Respiratory Medicine, Juntendo University Faculty of Medicine & Graduate School of Medicine, 2-1-1 Hongo, Bunkyo-Ku, Tokyo 113-8421 (Japan); The Study Group of Pneumothorax and Cystic Lung Diseases, 4-8-1 Seta, Setagaya-Ku, Tokyo 158-0095 (Japan); Johkoh, Takeshi [Department of Radiology, Kinki Central Hospital of Mutual Aid Association of Public School Teachers, Kurumazuka 3-1, Itami, Hyogo 664-0872 (Japan); Fujimoto, Kiminori [Department of Radiology, Kurume University School of Medicine and Center for Diagnostic Imaging, Kurume University Hospital, 67 Asahi-machi, Kurume, Fukuoka 830-0011 (Japan); Sakai, Fumikazu [Department of Diagnostic Radiology, Saitama International Medical Center, Saitama Medical University, 1397-1 Yamane, Hidaka, Saitama 350-1298 (Japan); Arakawa, Hiroaki [Department of Radiology, Dokkyo Medical University, 880 Kita-Kobayashi, Mibu, Tochigi 321-0293 (Japan); Kurihara, Masatoshi [The Study Group of Pneumothorax and Cystic Lung Diseases, 4-8-1 Seta, Setagaya-Ku, Tokyo 158-0095 (Japan); Pneumothorax Center, Nissan Tamagawa Hospital, 4-8-1 Seta, Setagaya-Ku, Tokyo 158-0095 (Japan); Kumasaka, Toshio [The Study Group of Pneumothorax and Cystic Lung Diseases, 4-8-1 Seta, Setagaya-Ku, Tokyo 158-0095 (Japan); Department of Pathology, Japanese Red Cross Medical Center, 4-1-22 Hiroo, Shibuya-Ku, Tokyo 150-0012 (Japan); Koike, Kengo; Takahashi, Kazuhisa [Division of Respiratory Medicine, Juntendo University Faculty of Medicine & Graduate School of Medicine, 2-1-1 Hongo, Bunkyo-Ku, Tokyo 113-8421 (Japan); Seyama, Kuniaki [Division of Respiratory Medicine, Juntendo University Faculty of Medicine & Graduate School of Medicine, 2-1-1 Hongo, Bunkyo-Ku, Tokyo 113-8421 (Japan); The Study Group of Pneumothorax and Cystic Lung Diseases, 4-8-1 Seta, Setagaya-Ku, Tokyo 158-0095 (Japan)

    2015-03-15

    Highlights: •In our series, the frequency of pulmonary nodules was higher than in the previous reports. •Our sporadic LAM patients had a lower frequency of renal AML than in that of previous reports. •LAM patients may have a high incidence of renal and hepatic cysts. •LAM cells may originate in the pelvis then spread via the axial lymphatic system. -- Abstract: Purpose: The aim was to characterize the computed tomographic (CT) findings from Japanese patients with lymphangioleiomyomatosis (LAM). Materials and methods: CT scans of the chest, abdomen, and pelvis from 124 patients with sporadic LAM (S-LAM, mean age, 37.4 years) and 14 patients with tuberous sclerosis complex (TSC)-LAM (mean age, 35.6 years) were analyzed. Results: Pulmonary nodules (18.8%) and hepatic angiomyolipoma (AML, 24.3%) were more common in our patients than those in previous reports. Compared with TSC-LAM, S-LAM group had a higher frequency of pulmonary nodules (28.6% vs 32.3%, P < 0.01) and lower frequencies of air-space consolidation (21.4% vs 2.4%, P < 0.01), pneumothorax (28.6% vs 8.1%, P = 0.02), pulmonary hilar lymphadenopathy (14.3% vs 0.8%, P < 0.01), renal AML (85.7% vs 17.4%, P < 0.01), hepatic AML (71.4% vs 17.4%, P < 0.01), and retrocrural lymphadenopathy (14.3% vs 1.4%, P = 0.04). Axial lymphatic abnormalities (i.e., thoracic duct dilatation, lymphadenopathy, and lymphangioleiomyoma) were most common in the pelvis and tended to decrease in incidence with increased distance from the pelvis. Conclusion: The incidence of some CT findings in Japanese patients differed from those in previous reports. Axial lymphatic abnormalities noted here suggest that the origin of LAM cells may be the pelvis.

  18. Contrast enhancement by arterial perfusion during computed tomography (computed tomographic arteriography) of the pancreatic disease

    International Nuclear Information System (INIS)

    Takaki, Yukiari

    1983-01-01

    Computed tomographic arteriography (CTA) was performed on 52 cases of pancreatic disease in which was suspected clinically, and in which other method failed to yield a definitive diagnosis. For CTA, 65% meglumine diatrizoate 20 ml, diluted 1:3, was injected via a catherter inserted in an artery connected with the pancreas and the change with time of the pacreas CT number was studied. The normal pancreas stains deeply and the best contrast enhancement was obtained between 17 to 21 seconds after instillation of contrast medium. In the CTA findings in pancreatic cancer, low density areas with irregular internal structures are characteristic, and these characteristics were seen even in minute pancreatic cancers which could not be recognized by CT or the intravenous bolus injection method. On the other hand, in chronic pancreatitis, even when differentiation from pancreatic cancer is difficult with arterial and venous encasement in angiography, as long as the chronic pancreatitis is not very advanced ischemic changes are not seen, and this permits differentiation form normal pancreas. This also facilitates differentiation between pancreatitis and pancreatic cancer. In the intravenous bolus injection method, the chronological change of contrast enhancement in the pancreas was studied and the best contrast enhancement was obtained after 60 to 120 seconds. This method revealed no findings peculiar to pancreatic cancer. Based on the above, CTA was found to be useful for making in contributing to establishing a definitive diagnosis, detecting minute pancreatic cancer and to differentiate pancreatic cancer from chronic pancreatitis. (author)

  19. Assessment in dogs tympanic bulla, through virtual tomographic endoscopy; Avaliacao de bulas timpanicas em caes, por meio da endoscopia tomografica virtual

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Luciana Carandina da; Sabino, Emanuelle Guidugli, E-mail: lucianacarandina@uol.com.br [Universidade Estadual Paulista Julio de Mesquita Filho (UNESP), Botucatu, SP (Brazil). Faculdade de Medicina Veterinaria. Dept. de Reproducao Animal e Radiologia Veterinaria; Vulcano, Luiz Carlos; Machado, Vania Maria de Vasconcelos [Universidade Estadual Paulista Julio de Mesquita Filho (UNESP), Botucatu, SP (Brazil). Faculdade de Medicina Veterinaria

    2012-07-01

    Dogs usually have problems related to the auditory canal. For the diagnosis of these pathologies, it is necessary a physical examination and, in some cases radiographic examination and computed tomography. The tympanic bulla is not easily visualized radiographically, since there is many structures of the brain overlaying the image obtained. The computed tomography has been the technique of choice to assess this structure faithfully. A new alternative assessment of the tympanic bulla is tomographic virtual endoscopy, which allows an improvement of the image obtained through the virtual tomographic technique. This paper provides information on the use of computed tomography, and a new technique, tomographic virtual endoscopy, in order to make the improvement of these techniques, and prove the reliability of these changes in the diagnosis of ear canals of dogs. Therefore, we performed the computed tomography of the tympanic bulla on healthy animals, and later performed image reconstruction in three-dimensional (3D) mode for virtual endoscopy. (author)

  20. 3D Tomographic Image Reconstruction using CUDA C

    International Nuclear Information System (INIS)

    Dominguez, J. S.; Assis, J. T.; Oliveira, L. F. de

    2011-01-01

    This paper presents the study and implementation of a software for three dimensional reconstruction of images obtained with a tomographic system using the capabilities of Graphic Processing Units(GPU). The reconstruction by filtered back-projection method was developed using the CUDA C, for maximum utilization of the processing capabilities of GPUs to solve computational problems with large computational cost and highly parallelizable. It was discussed the potential of GPUs and shown its advantages to solving this kind of problems. The results in terms of runtime will be compared with non-parallelized implementations and must show a great reduction of processing time. (Author)

  1. Assessment of Normal Eyeball Protrusion Using Computed Tomographic Imaging and Three-Dimensional Reconstruction in Korean Adults.

    Science.gov (United States)

    Shin, Kang-Jae; Gil, Young-Chun; Lee, Shin-Hyo; Kim, Jeong-Nam; Yoo, Ja-Young; Kim, Soon-Heum; Choi, Hyun-Gon; Shin, Hyun Jin; Koh, Ki-Seok; Song, Wu-Chul

    2017-01-01

    The aim of the present study was to assess normal eyeball protrusion from the orbital rim using two- and three-dimensional images and demonstrate the better suitability of CT images for assessment of exophthalmos. The facial computed tomographic (CT) images of Korean adults were acquired in sagittal and transverse views. The CT images were used in reconstructing three-dimensional volume of faces using computer software. The protrusion distances from orbital rims and the diameters of eyeballs were measured in the two views of the CT image and three-dimensional volume of the face. Relative exophthalmometry was calculated by the difference in protrusion distance between the right and left sides. The eyeball protrusion was 4.9 and 12.5 mm in sagittal and transverse views, respectively. The protrusion distances were 2.9 mm in the three-dimensional volume of face. There were no significant differences between right and left sides in the degree of protrusion, and the difference was within 2 mm in more than 90% of the subjects. The results of the present study will provide reliable criteria for precise diagnosis and postoperative monitoring using CT imaging of diseases such as thyroid-associated ophthalmopathy and orbital tumors.

  2. Comparison between computed tomographic and surgical findings in nine large-breed dogs with lumbosacral stenosis

    International Nuclear Information System (INIS)

    Jones, J.C.; Sorjonen, D.C.; Simpson, S.T.; Coates, J.R.; Lenz, S.D.; Hathcock, J.T.; Agee, M.W.; Bartels, J.E.

    1996-01-01

    In a three-year prospective study, computed tomographic (CT) and surgical findings were compared for nine large breed dogs with lumbosacral stenosis. Surgically-excised tissue was examined histologically in seven dogs and additional necropsy evaluation was performed in one dog. The CT abnormalities observed at sites of confirmed cauda equina compression were: loss of epidural fat, increased soft tissue opacity, bulging of the intervertebral disc margin, spondylosis, thecal sac displacement, narrowed intervertebral foramen, narrowed vertebral canal, thickened articular process, articular process subluxation, articular process osteophyte, and telescoped sacral lamina. The CT characteristics of lumbosacral degenerative disease and discospondylitis were similar to those described in humans. In three dogs, CT findings at the site of cauda equina compression were consistent with congenital or developmental spinal stenosis, but the method of surgical exposure precluded confirmation. Epidural fibrosis (eight dogs) and multi-level CT abnormalities (six dogs) were identified but the cause(s) and significance were unknown

  3. Multislice coronary computed tomographic angiography in emergency department presentations of unsuspected acute myocardial infarction.

    Science.gov (United States)

    Hecht, Harvey S; Bhatti, Tandeep

    2009-01-01

    Coronary computed tomographic angiography (CCTA) is not indicated in the setting of acute myocardial infarction in the emergency department (ED). Nonetheless, acute coronary syndromes may have atypical presentations, and CCTA may be inadvertently performed in this setting. This study was designed to determine the frequency and characteristics of CCTA imaging of unsuspected acute myocardial infarction in the ED. All CCTAs performed in the ED at Lenox Hill Hospital were reviewed for clinical indications and subsequent course; patients with documented acute myocardial infarction were identified. Of the 500 CCTAs performed on ED patients in the Lenox Hill laboratory, 5 patients (1%) were imaged during the initial phase of an unsuspected acute myocardial infarction; in all cases the CCTAs were key to the diagnosis. The imaging characteristics were (1) total or subtotal occlusion and (2) transmural hypodensity in the infarct area. Although acute myocardial infarction on CCTA in ED patients is an infrequent event, proper and prompt recognition is critical for appropriate patient care, particularly as applications to the ED increase.

  4. TomoEED: Fast Edge-Enhancing Denoising of Tomographic Volumes.

    Science.gov (United States)

    Moreno, J J; Martínez-Sánchez, A; Martínez, J A; Garzón, E M; Fernández, J J

    2018-05-29

    TomoEED is an optimized software tool for fast feature-preserving noise filtering of large 3D tomographic volumes on CPUs and GPUs. The tool is based on the anisotropic nonlinear diffusion method. It has been developed with special emphasis in the reduction of the computational demands by using different strategies, from the algorithmic to the high performance computing perspectives. TomoEED manages to filter large volumes in a matter of minutes in standard computers. TomoEED has been developed in C. It is available for Linux platforms at http://www.cnb.csic.es/%7ejjfernandez/tomoeed. gmartin@ual.es, JJ.Fernandez@csic.es. Supplementary data are available at Bioinformatics online.

  5. A fast multi-resolution approach to tomographic PIV

    Science.gov (United States)

    Discetti, Stefano; Astarita, Tommaso

    2012-03-01

    Tomographic particle image velocimetry (Tomo-PIV) is a recently developed three-component, three-dimensional anemometric non-intrusive measurement technique, based on an optical tomographic reconstruction applied to simultaneously recorded images of the distribution of light intensity scattered by seeding particles immersed into the flow. Nowadays, the reconstruction process is carried out mainly by iterative algebraic reconstruction techniques, well suited to handle the problem of limited number of views, but computationally intensive and memory demanding. The adoption of the multiplicative algebraic reconstruction technique (MART) has become more and more accepted. In the present work, a novel multi-resolution approach is proposed, relying on the adoption of a coarser grid in the first step of the reconstruction to obtain a fast estimation of a reliable and accurate first guess. A performance assessment, carried out on three-dimensional computer-generated distributions of particles, shows a substantial acceleration of the reconstruction process for all the tested seeding densities with respect to the standard method based on 5 MART iterations; a relevant reduction in the memory storage is also achieved. Furthermore, a slight accuracy improvement is noticed. A modified version, improved by a multiplicative line of sight estimation of the first guess on the compressed configuration, is also tested, exhibiting a further remarkable decrease in both memory storage and computational effort, mostly at the lowest tested seeding densities, while retaining the same performances in terms of accuracy.

  6. Computed tomographic findings of skeletal muscles in amyotrophic lateral sclerosis (ALS)

    International Nuclear Information System (INIS)

    Takahashi, Ryosuke; Imai, Terukuni; Sadashima, Hiromichi; Matsumoto, Sadayuki; Yamamoto, Toru; Kusaka, Hirobumi; Yamasaki, Masahiro; Maya, Kiyomi; Tanabe, Masaya

    1989-01-01

    We evaluated the Computed Tomographic (CT) findings of skeletal muscles in 12 cases of amyotrophic lateral sclerosis (ALS), 1 case of spinal progressive muscular atrophy (SPMA), and 1 case of Kugelberg-Welander disease. CT examination was performed in the neck, shoulders, abdomen, pelvis, thighs, and lower legs, 15 muscles were selected for evaluation. The following muscles tended to be affected: m. transversospinalis (12 cases were abnormal), m. deltoideus (10), m. subscapularis (10), m. infraspinatus (10), mm. dorsi (12), hamstring muscles (14), m. tibialis anterior (14), and m. triceps surae (14). On the contrary, the following muscles tended to be preserved: m. sternocleidomastoideus (only 7 cases were abnormal), m. psoas major (7), m. gluteus maximus (7), m. rectus femoris (7), m. sartorius (7) and m. gracilis (6). The distribution of the muscles affected showed neither proximal nor distal dominancy. As the disease advanced, however, all the muscles became affected without any severity. CT findings of skeletal muscles in ALS were characterized by muscle atrophy and fat infiltration, which showed a patchy, linear, or moth-eaten appearance. In mildly affected cases, there was muscle atrophy without internal architectual changes. In moderately affected cases, muscle atrophy advanced and internal architectural changes (patchy, linear, and moth-eaten fat infiltration) became evident. In most advanced cases, every muscle showed a ragged appearance because of severe muscle atrophy and internal architectural changes. These findings were well distinguished from those of SPMA, which resembled the CT pattern of primary muscle diseases. (author)

  7. Computed tomographic findings of skeletal muscles in amyotrophic lateral sclerosis (ALS)

    Energy Technology Data Exchange (ETDEWEB)

    Takahashi, Ryosuke; Imai, Terukuni; Sadashima, Hiromichi; Matsumoto, Sadayuki; Yamamoto, Toru; Kusaka, Hirobumi; Yamasaki, Masahiro; Maya, Kiyomi; Tanabe, Masaya (Kitano Hospital, Osaka (Japan))

    1989-04-01

    We evaluated the Computed Tomographic (CT) findings of skeletal muscles in 12 cases of amyotrophic lateral sclerosis (ALS), 1 case of spinal progressive muscular atrophy (SPMA), and 1 case of Kugelberg-Welander disease. CT examination was performed in the neck, shoulders, abdomen, pelvis, thighs, and lower legs, 15 muscles were selected for evaluation. The following muscles tended to be affected: m. transversospinalis (12 cases were abnormal), m. deltoideus (10), m. subscapularis (10), m. infraspinatus (10), mm. dorsi (12), hamstring muscles (14), m. tibialis anterior (14), and m. triceps surae (14). On the contrary, the following muscles tended to be preserved: m. sternocleidomastoideus (only 7 cases were abnormal), m. psoas major (7), m. gluteus maximus (7), m. rectus femoris (7), m. sartorius (7) and m. gracilis (6). The distribution of the muscles affected showed neither proximal nor distal dominancy. As the disease advanced, however, all the muscles became affected without any severity. CT findings of skeletal muscles in ALS were characterized by muscle atrophy and fat infiltration, which showed a patchy, linear, or moth-eaten appearance. In mildly affected cases, there was muscle atrophy without internal architectual changes. In moderately affected cases, muscle atrophy advanced and internal architectural changes (patchy, linear, and moth-eaten fat infiltration) became evident. In most advanced cases, every muscle showed a ragged appearance because of severe muscle atrophy and internal architectural changes. These findings were well distinguished from those of SPMA, which resembled the CT pattern of primary muscle diseases. (author).

  8. Three dimensional reconstruction of tomographic images of the retina

    International Nuclear Information System (INIS)

    Glittenberg, C.; Zeiler, F.; Falkner, C.; Binder, S.; Povazay, B.; Hermann, B.; Drexler, W.

    2007-01-01

    The development of a new display system for the three-dimensional visualization of tomographic images in ophthalmology. Specifically, a system that can use stacks of B-mode scans from an ultrahigh resolution optical tomography examination to vividly display retinal specimens as three-dimensional objects. Several subroutines were programmed in the rendering and raytracing program Cinema 4D XL 9.102 Studio Bundle (Maxon Computer Inc., Friedrichsburg, Germany), which could process stacks of tomographic scans into three-dimensional objects. Ultrahigh resolution optical coherence tomography examinations were performed on patients with various retinal pathologies and post processed with the subroutines that had been designed. All ultrahigh resolution optical coherence tomographies were performed with a titanium: sapphire based ultra broad bandwidth (160 nm) femtosecond laser system (INTEGRAL, Femtolasers Productions GmbH. Vienna Austria) with an axial resolution of 3 μm. A new three dimensional display system for tomographic images in ophthalmology was developed, which allows a highly vivid display of physiological and pathological structures of the retina. The system also distinguishes itself through its high interactivity and adaptability. This new display system allows the visualization of physiological and pathological structures of the retina in a new way, which will give us new insight into their morphology and development. (author) [de

  9. Regrowth patterns of supratentorial gliomas: estimation from computed tomographic scans

    Energy Technology Data Exchange (ETDEWEB)

    Tsuboi, K.; Yoshii, Y.; Nakagawa, K.; Maki, Y.

    1986-12-01

    To clarify the regrowth patterns of benign and malignant gliomas, we chose 27 intervals (between two operations or between an operation and autopsy) from 21 patients with pathologically verified recurrent supratentorial gliomas. Serial computed tomographic (CT) scans of these cases were analyzed to determine the doubling time (Td) calculated from the change in volume of enhanced and low density areas, the enhancement effect graded from 0 to 4 according to the Hounsfield number, and the presence of dissemination and contralateral extension. We studied 5 benign gliomas (including 1 case of radiation necrosis), 8 malignant astrocytomas, and 8 glioblastomas. The Td's of enhanced areas on CT scans of benign gliomas, malignant astrocytomas, and glioblastomas were 937 +/- 66.5 days, 65.1 +/- 29.4 days, and 48.1 +/- 20.9 days, respectively. The Td's of low density areas were 895 +/- 130.6 days, 70.8 +/- 22.2 days, and 50.5 +/- 14.7 days. There was a significant correlation between the Td's of the enhanced and low density areas (0.97). The enhancement effect increased at recurrence in 55% of the cases, with an average increase of 1.1 grades. The increase in enhancement effect at recurrence showed a tendency to become smaller as the tumor's degree of anaplasia increased. Radiotherapy was effective in significantly retarding the growth rate of malignant gliomas, whose Td's were doubled. Although the Td's of both enhanced and low density areas of benign gliomas were significantly longer than those of malignant gliomas, there was no significant difference in the Td's of enhanced areas between malignant astrocytomas and glioblastomas.

  10. Clamshell tomograph

    International Nuclear Information System (INIS)

    Derenzo, S. E.; Budinger, Th. F.

    1984-01-01

    In brief, the invention is a tomograph modified to be in a clamshell configuration so that the ring or rings may be moved to multiple sampling positions. The tomograph includes an array of detectors arranged in successive adjacent relative locations along a closed curve in a first position in a selected plane, and means for securing the detectors in the relative locations in a first sampling position. The securing means is movable in the plane in two sections and pivotable at one point and only one point to enable movement of at least one of the sections to a second sampling position out of the closed curve so that the ends of the section which are opposite the point are moved apart a predetermined space

  11. Tomographic and analog 3-D simulations using NORA. [Non-Overlapping Redundant Image Array formed by multiple pinholes

    Science.gov (United States)

    Yin, L. I.; Trombka, J. I.; Bielefeld, M. J.; Seltzer, S. M.

    1984-01-01

    The results of two computer simulations demonstrate the feasibility of using the nonoverlapping redundant array (NORA) to form three-dimensional images of objects with X-rays. Pinholes admit the X-rays to nonoverlapping points on a detector. The object is reconstructed in the analog mode by optical correlation and in the digital mode by tomographic computations. Trials were run with a stick-figure pyramid and extended objects with out-of-focus backgrounds. Substitution of spherical optical lenses for the pinholes increased the light transmission sufficiently that objects could be easily viewed in a dark room. Out-of-focus aberrations in tomographic reconstruction could be eliminated using Chang's (1976) algorithm.

  12. Tomographic flow cytometry assisted by intelligent wavefronts analysis

    Science.gov (United States)

    Merola, F.; Memmolo, P.; Miccio, L.; Mugnano, M.; Ferraro, P.

    2017-06-01

    High-throughput single-cell analysis is a challenging target for implementing advanced biomedical applications. An excellent candidate for this aim is label-free tomographic phase microscopy. However, in-line tomography is very difficult to be implemented in practice, as it requires complex setup for rotating the sample and/or illuminate the cell along numerous directions [1]. We exploit random rolling of cells while they are flowing along a microfluidic channel demonstrating that it is possible to obtain in-line phase-contrast tomography by adopting strategies for intelligent wavefronts analysis thus obtaining complete retrieval of both 3D-position and orientation of rotating cells [2]. Thus, by numerical wavefront analysis a-priori knowledge of such information is no longer needed. This approach makes continuos-flow cyto-tomography suitable for practical operation in real-world, single-cell analysis and with substantial simplification of the optical system avoiding any mechanical/optical scanning of light source. Demonstration is given for different classes of biosamples, red-blood-cells (RBCs), diatom algae and fibroblast cells [3]. Accurate characterization of each type of cells is reported despite their very different nature and materials content, thus showing the proposed method can be extended, by adopting two alternate strategies of wavefront-analysis, to many classes of cells. In particular, for RBCs we furnish important parameters as 3D morphology, Corpuscular Hemoglobin (CH), Volume (V), and refractive index (RI) for each single cell in the total population [3]. This could open a new route in blood disease diagnosis, for example for the isolation and characterization of "foreign" cells in the blood stream, the so called Circulating Tumor Cells (CTC), early manifestation of metastasis.

  13. Diagnostic performance of 64-slice multidetector coronary computed tomographic angiography in women.

    Science.gov (United States)

    Jug, Borut; Gupta, Mohit; Papazian, Jenny; Li, Dong; Tsang, Janet; Bhatia, Harpreet; Karlsberg, Ronald; Budoff, Matthew

    2012-12-01

    Diagnostic approach to chest pain in women is challenging, but still under-investigated. The purpose of this study was to assess the diagnostic performance of 64-slice multidetector coronary computed tomographic angiography (CCTA) in women with chest pain. We included 606 patients--255 women and 351 men (mean age 61 ± 12 years for both)--who had been referred for a CCTA and an invasive coronary angiography (diagnostic standard) because of chest pain, either as part of clinical work-up in two urban medical centers or as part of the multicenter ACCURACY trial. On a patient-based model, the sensitivity, specificity, and positive predictive value (PPV) and negative predictive value to detect ≥50% and ≥70% stenosis were 98%, 84%, 87%, and 97% and 96%, 83%, 77%, and 97%, respectively, for women and 97%, 83%, 89%, and 95% and 94%, 91%, 90%, and 94%, respectively, for men. There were no statistically significant differences between men and women in diagnostic performance measures except for the PPV of detecting a ≥70% stenosis (P = .007). In women with chest pain, 64-slice multidetector CCTA is at least as sensitive and specific as in men. Our findings suggest that CCTA is a promising diagnostic tool for timely detection and/or exclusion of CAD in symptomatic intermediate-risk female populations.

  14. Accessory Renal Artery Stenosis and Hypertension: Are These Correlated? Evaluation Using Multidetector-Row Computed Tomographic Angiography

    Energy Technology Data Exchange (ETDEWEB)

    Saba, L.; Sanfilippo, R.; Montisci, R.; Conti, M.; Mallarini, G. (Dept. of Imaging Science and Dept. of Vascular Surgery, Policlinico Universitario, Cagliari (Italy))

    2008-04-15

    Background: Renal artery stenosis may produce hypertension, and this condition is referred to as renovascular hypertension (RVH). Purpose: To evaluate, by using multidetector-row spiral computed tomographic angiography (MDCTA), whether a relationship between accessory renal artery stenosis and hypertension may be hypothesized. Material and Methods: 214 patients (142 males, 72 females; mean age 66 years) who had previously undergone an MDCTA to study the abdominal vasculature were retrospectively studied. Patients with renal artery stenosis (RAS) were excluded from this analysis. The patients were studied by means of a four-detector-row CT, and scans were obtained after intravenous bolus administration of 110-140 ml of a nonionic contrast material with a 3-6 ml/s flow rate. As a second step, by means of statistical analysis, hypertension data were compared with findings of accessory artery stenosis. Two radiologists first independently reviewed the MDCTA images and then, in case of disagreement, in consensus. Interobserver agreement was calculated for all measurements. Results: The overall number of detected accessory renal arteries was 74 in 56 of the 214 patients. Accessory renal artery stenosis was detected in 21 of the 56 patients. There was a difference in the prevalence of hypertension between patients with (n = 21) and without (n = 35) accessory renal artery stenosis (P = 0.0187). Interobserver agreement was good (kappa value 0.733). Conclusion: Any statistical association between the presence of accessory renal artery stenosis and hypertension could not be disclosed. However, accessory renal artery stenosis, detected by MDCTA, is an important pathological sign that the radiologist has to assess in the light of its possible association with hypertension

  15. Accessory Renal Artery Stenosis and Hypertension: Are These Correlated? Evaluation Using Multidetector-Row Computed Tomographic Angiography

    International Nuclear Information System (INIS)

    Saba, L.; Sanfilippo, R.; Montisci, R.; Conti, M.; Mallarini, G.

    2008-01-01

    Background: Renal artery stenosis may produce hypertension, and this condition is referred to as renovascular hypertension (RVH). Purpose: To evaluate, by using multidetector-row spiral computed tomographic angiography (MDCTA), whether a relationship between accessory renal artery stenosis and hypertension may be hypothesized. Material and Methods: 214 patients (142 males, 72 females; mean age 66 years) who had previously undergone an MDCTA to study the abdominal vasculature were retrospectively studied. Patients with renal artery stenosis (RAS) were excluded from this analysis. The patients were studied by means of a four-detector-row CT, and scans were obtained after intravenous bolus administration of 110-140 ml of a nonionic contrast material with a 3-6 ml/s flow rate. As a second step, by means of statistical analysis, hypertension data were compared with findings of accessory artery stenosis. Two radiologists first independently reviewed the MDCTA images and then, in case of disagreement, in consensus. Interobserver agreement was calculated for all measurements. Results: The overall number of detected accessory renal arteries was 74 in 56 of the 214 patients. Accessory renal artery stenosis was detected in 21 of the 56 patients. There was a difference in the prevalence of hypertension between patients with (n = 21) and without (n = 35) accessory renal artery stenosis (P = 0.0187). Interobserver agreement was good (kappa value 0.733). Conclusion: Any statistical association between the presence of accessory renal artery stenosis and hypertension could not be disclosed. However, accessory renal artery stenosis, detected by MDCTA, is an important pathological sign that the radiologist has to assess in the light of its possible association with hypertension

  16. A new fast algorithm for the evaluation of regions of interest and statistical uncertainty in computed tomography

    International Nuclear Information System (INIS)

    Huesman, R.H.

    1984-01-01

    A new algorithm for region of interest evaluation in computed tomography is described. Region of interest evaluation is a technique used to improve quantitation of the tomographic imaging process by summing (or averaging) the reconstructed quantity throughout a volume of particular significance. An important application of this procedure arises in the analysis of dynamic emission computed tomographic data, in which the uptake and clearance of radiotracers are used to determine the blood flow and/or physiologica function of tissue within the significant volume. The new algorithm replaces the conventional technique of repeated image reconstructions with one in which projected regions are convolved and then used to form multiple vector inner products with the raw tomographic data sets. Quantitation of regions of interest is made without the need for reconstruction of tomographic images. The computational advantage of the new algorithm over conventional methods is between factors of 20 and of 500 for typical applications encountered in medical science studies. The greatest benefit is the ease with which the statistical uncertainty of the result is computed. The entire covariance matrix for the evaluation of regions of interest can be calculated with relatively few operations. (author)

  17. Quantitative analysis of normal thallium-201 tomographic studies

    International Nuclear Information System (INIS)

    Eisner, R.L.; Gober, A.; Cerqueira, M.

    1985-01-01

    To determine the normal (nl) distribution of Tl-201 uptake post exercise (EX) and at redistribution (RD) and nl washout, Tl-201 rotational tomographic (tomo) studies were performed in 40 subjects: 16 angiographic (angio) nls and 24 nl volunteers (12 from Emory and 12 from Yale). Oblique angle short axis slices were subjected to maximal count circumferential profile analysis. Data were displayed as a ''bullseye'' functional map with the apex at the center and base at the periphery. The bullseye was not uniform in all regions because of the variable effects of attenuation and resolution at different view angles. In all studies, the septum: lateral wall ratio was 1.0 in males and approximately equal to 1.0 in females. This occurred predominantly because of anterior defects due to breast soft tissue attenuation. EX and RD bullseyes were similar. Using a bi-exponential model for Tl kinetics, 4 hour normalized washout ranged 49-54% in each group and showed minimal variation between walls throughout the bullseye. Thus, there are well defined variations in Tl-201 uptake in the nl myocardium which must be taken into consideration when analyzing pt data. Because of these defects and the lack of adequate methods for attenuation correction, quantitative analysis of Tl-201 studies must include direct comparison with gender-matched nl data sets

  18. 16-Detector row computed tomographic coronary angiography in patients undergoing evaluation for aortic valve replacement: comparison with catheter angiography

    International Nuclear Information System (INIS)

    Manghat, N.E.; Morgan-Hughes, G.J.; Broadley, A.J.; Undy, M.B.; Wright, D.; Marshall, A.J.; Roobottom, C.A.

    2006-01-01

    Aim: To evaluate the diagnostic accuracy of 16-detector row computed tomography (CT) in assessing haemodynamically significant coronary artery stenoses in patients under evaluation for aortic stenosis pre-aortic valve replacement. Subjects and methods: Forty consecutive patients under evaluation for severe aortic stenosis and listed for cardiac catheterization before potential aortic valve replacement underwent coronary artery calcium (CAC) scoring and retrospective electrocardiogram (ECG)-gated multi-detector row computed tomographic coronary angiography (MDCTA) using a GE Lightspeed 16-detector row CT within 1 month of invasive coronary angiography (ICA) for comparative purposes. All 13 major coronary artery segments of the American Heart Association model were evaluated for the presence of ≥50% stenosis and compared to the reference standard. Data were analysed on a segment-by-segment basis and also in 'whole patient' terms. Results: A total of 412/450 segments from 35 patients were suitable for analysis. The overall accuracy of MDCTA for detection of segments with ≥50% stenosis was high, with a sensitivity of 81.3%, specificity 95.0%, positive predictive value (PPV) 57.8%, and negative predictive value (NPV) 98.4%. On a 'whole-patient' basis, 100% (19/19) of patients with significant coronary disease were correctly identified and there were no false-negatives. Excluding patients with CAC >1000 from the analysis improved the accuracy of MDCTA to: sensitivity 90%, specificity 98.1%, PPV 60%, NPV 99.7%. Conclusion: Non-invasive 16-detector row MDCTA accurately excludes significant coronary disease in patients with severe aortic stenosis undergoing evaluation before aortic valve replacement and in whom ICA can therefore be avoided. Its segment-by-segment accuracy is improved further if CAC > 1000 is used as a gatekeeper to MDCTA

  19. Soil physical and X-ray computed tomographic measurements to investigate small-scale structural differences under strip tillage compared to mulch till and no-till

    Science.gov (United States)

    Pöhlitz, Julia; Rücknagel, Jan; Schlüter, Steffen; Vogel, Hans-Jörg

    2017-04-01

    In recent years there has been an increasing application of conservation tillage techniques where the soil is no longer turned, but only loosened or left completely untilled. Dead plant material remains on the soil surface, which provides environmental and economic benefits such as the conservation of water, preventing soil erosion and saving time during seedbed preparation. There is a variety of conservation tillage systems, e.g. mulch till, no-till and strip tillage, which is a special feature. In strip tillage, the seed bed is divided into a seed zone (strip-till within the seed row: STWS) and a soil management zone (strip-till between the seed row: STBS). However, each tillage application affects physical soil properties and processes. Here, the combined application of classical soil mechanical and computed tomographic methods is used on a Chernozem (texture 0-30 cm: silt loam) to show small-scale structural differences under strip tillage (STWS, STBS) compared to no-till (NT) and mulch till (MT). In addition to the classical soil physical parameters dry bulk density and saturated conductivity (years: 2012, 2014, 2015) at soil depths 2-8 and 12-18 cm, stress-strain tests were carried out to map mechanical behavior. The stress-strain tests were performed for a load range from 5-550 kPa at 12-18 cm depth (year 2015). Mechanical precompression stress was determined on the stress-dry bulk density curves. Further, CT image cross sections and computed tomographic examinations (average pore size, porosity, connectivity, and anisotropy) were used from the same soil samples. For STBS and NT, a significant increase in dry bulk density was observed over the course of time compared to STWS and MT, which was more pronounced at 2-8 cm than at 12-18 cm depth. Despite higher dry bulk density, STBS displayed higher saturated conductivity in contrast to STWS, which can be attributed to higher earthworm abundance. In strip tillage, structural differences were identified

  20. X-rays computed tomographic scans of lower limb and trunk muscles in facioscapulohumeral muscular dystrophy

    Energy Technology Data Exchange (ETDEWEB)

    Horikawa, Hirosei; Mano, Yukio; Takayanagi, Tetsuya [Nara Medical Univ., Kashihara (Japan); Takahashi, Keiichi; Nishio, Hisahide

    1992-10-01

    X-rays computed tomographic (CT) scans of muscles of the lower limbs and the trunk in 14 patients with facioscapulohumeral muscular dystrophy (FSH) were studied. The CT scans showed that the affected muscles were decreased in density and size. The laterality of muscular involvement was sometimes observed. The muscular lesions in the lower limbs showed proximal distribution. In the thigh, the hamstrings were affected first, the adductor muscles second, and then the muscular involvement progressed to the quadriceps femoris muscle. In the lower leg, the gastrocnemius and soleus muscles were relatively spared as compared with the tibialis anterior muscle. In the lumbar girdle, the abdominal muscles were involved first, the gluteal muscles second, the back muscles third, and the psoas major muscle were relatively spared. The muscular weakness of this distribution exacerbated lumbar lordosis. The neck muscles were less affected than those of the lumbar girdle. The CT scans in FSH demonstrated the characteristic pattern of muscular involvement, which differed from the inherited muscular diseases such as Duchenne muscular dystrophy, myotonic dystrophy, and others. (author).

  1. X-rays computed tomographic scans of lower limb and trunk muscles in facioscapulohumeral muscular dystrophy

    International Nuclear Information System (INIS)

    Horikawa, Hirosei; Mano, Yukio; Takayanagi, Tetsuya; Takahashi, Keiichi; Nishio, Hisahide.

    1992-01-01

    X-rays computed tomographic (CT) scans of muscles of the lower limbs and the trunk in 14 patients with facioscapulohumeral muscular dystrophy (FSH) were studied. The CT scans showed that the affected muscles were decreased in density and size. The laterality of muscular involvement was sometimes observed. The muscular lesions in the lower limbs showed proximal distribution. In the thigh, the hamstrings were affected first, the adductor muscles second, and then the muscular involvement progressed to the quadriceps femoris muscle. In the lower leg, the gastrocnemius and soleus muscles were relatively spared as compared with the tibialis anterior muscle. In the lumbar girdle, the abdominal muscles were involved first, the gluteal muscles second, the back muscles third, and the psoas major muscle were relatively spared. The muscular weakness of this distribution exacerbated lumbar lordosis. The neck muscles were less affected than those of the lumbar girdle. The CT scans in FSH demonstrated the characteristic pattern of muscular involvement, which differed from the inherited muscular diseases such as Duchenne muscular dystrophy, myotonic dystrophy, and others. (author)

  2. Feature-guided analysis for reduction of false positives in CAD of polyps for computed tomographic colonography

    International Nuclear Information System (INIS)

    Naeppi, Janne; Yoshida, Hiroyuki

    2003-01-01

    We evaluated the effect of our novel technique of feature-guided analysis of polyps on the reduction of false-positive (FP) findings generated by our computer-aided diagnosis (CAD) scheme for the detection of polyps from computed tomography colonographic data sets. The detection performance obtained by use of feature-guided analysis in the segmentation and feature analysis of polyp candidates was compared with that obtained by use of our previously employed fuzzy clustering technique. We also evaluated the effect of a feature called modified gradient concentration (MGC) on the detection performance. A total of 144 data sets, representing prone and supine views of 72 patients that included 14 patients with 21 colorectal polyps 5-25 mm in diameter, were used in the evaluation. At a 100% by-patient (95% by-polyp) detection sensitivity, the FP rate of our CAD scheme with feature-guided analysis based on round-robin evaluation was 1.3 (1.5) FP detections per patient. This corresponds to a 70-75 % reduction in the number of FPs obtained by use of fuzzy clustering at the same sensitivity levels. Application of the MGC feature instead of our previously used gradient concentration feature did not improve the detection result. The results indicate that feature-guided analysis is useful for achieving high sensitivity and a low FP rate in our CAD scheme

  3. The Role of Bone Subtraction Computed Tomographic Angiography in Determining Intracranial Aneurysms in Non-Traumatic Subarachnoid Hemorrhage

    International Nuclear Information System (INIS)

    Kayhan, Aysegul; Koc, Osman; Keskin, Suat; Keskin, Fatih

    2014-01-01

    The presence of blood in the subarachnoid space is an acute pathology with a serious risk of death and complications. The most common etiology (approximately 80%) is intracranial aneurysm. The aim of this study was to assess the role of bone subtracted computed tomographic angiography (BSCTA), a novel and noninvasive method for determining and characterizing intracranial aneurysms. Sixty consecutive patients with clinically suspected non-traumatic subarachnoid hemorrhage (SAH) were considered to enter the study. The subtraction quality was inadequate in ten patients; thus, they were excluded, leaving 50 patients (84.4%) in the study. Bone subtracted and non-subtracted 3D images were obtained from the BSCTA raw data sets. All images obtained by digital subtraction angiography (DSA), BSCTA, and computed tomographic angiography (CTA) were evaluated for the presence or absence of an aneurysm and the location, minimal sac diameter, and neck size ratio of the aneurysm. DSA was considered as the gold standard during the evaluation of the data. Of the 50 patients who participated in this study, 11 had no aneurysms as determined by both CTA and DSA. Examination of the remaining 39 patients revealed the presence of 51 aneurysms. While 3D-CTA could not detect six aneurysms that were located in the base of the skull, 3D-BSCTA easily detected them. Moreover, five aneurysms were only partially detected by 3D-CTA. According to this data, the sensitivity of 3D-BSCTA and 3D-CTA was calculated as 98% and 86.3%, respectively; the specificity was calculated as 100% and 90.9%, respectively, per aneurysm; and the sensitivity of 100% for 3D-BSCTA and 98% for 3D-CTA was achieved by using combined images with multi-planar reconstruction (MPR) and maximum intensity projection (MIP). BSCTA detected and characterized the aneurysms as well as DSA, and BSCTA and DSA gave concordant results in detecting aneurysms. BSCTA is easily accessible, less time consuming, and most importantly, a non

  4. The Role of Bone Subtraction Computed Tomographic Angiography in Determining Intracranial Aneurysms in Non-Traumatic Subarachnoid Hemorrhage

    Science.gov (United States)

    Kayhan, Aysegul; Koc, Osman; Keskin, Suat; Keskin, Fatih

    2014-01-01

    Background: The presence of blood in the subarachnoid space is an acute pathology with a serious risk of death and complications. The most common etiology (approximately 80%) is intracranial aneurysm. Objectives: The aim of this study was to assess the role of bone subtracted computed tomographic angiography (BSCTA), a novel and noninvasive method for determining and characterizing intracranial aneurysms. Patients and Methods: Sixty consecutive patients with clinically suspected non-traumatic subarachnoid hemorrhage (SAH) were considered to enter the study. The subtraction quality was inadequate in ten patients; thus, they were excluded, leaving 50 patients (84.4%) in the study. Bone subtracted and non-subtracted 3D images were obtained from the BSCTA raw data sets. All images obtained by digital subtraction angiography (DSA), BSCTA, and computed tomographic angiography (CTA) were evaluated for the presence or absence of an aneurysm and the location, minimal sac diameter, and neck size ratio of the aneurysm. DSA was considered as the gold standard during the evaluation of the data. Results: Of the 50 patients who participated in this study, 11 had no aneurysms as determined by both CTA and DSA. Examination of the remaining 39 patients revealed the presence of 51 aneurysms. While 3D-CTA could not detect six aneurysms that were located in the base of the skull, 3D-BSCTA easily detected them. Moreover, five aneurysms were only partially detected by 3D-CTA. According to this data, the sensitivity of 3D-BSCTA and 3D-CTA was calculated as 98% and 86.3%, respectively; the specificity was calculated as 100% and 90.9%, respectively, per aneurysm; and the sensitivity of 100% for 3D-BSCTA and 98% for 3D-CTA was achieved by using combined images with multi-planar reconstruction (MPR) and maximum intensity projection (MIP). BSCTA detected and characterized the aneurysms as well as DSA, and BSCTA and DSA gave concordant results in detecting aneurysms. Conclusions: BSCTA is

  5. Three-dimensional analysis and display of medical images

    International Nuclear Information System (INIS)

    Bajcsy, R.

    1985-01-01

    Until recently, the most common medical images were X-rays on film analyzed by an expert, ususally a radiologist, who used, in addition to his/her visual perceptual abilities, knowledge obtained through medical studies, and experience. Today, however, with the advent of various imaging techniques, X-ray computerized axial tomographs (CAT), positron emission tomographs (PET), ultrasound tomographs, nuclear magnetic resonance tomographs (NMR), just to mention a few, the images are generated by computers and displayed on computer-controlled devices; so it is appropriate to think about more quantitative and perhaps automated ways of data analysis. Furthermore, since the data are generated by computer, it is only natural to take advantage of the computer for analysis purposes. In addition, using the computer, one can analyze more data and relate different modalities from the same subject, such as, for example, comparing the CAT images with PET images from the same subject. In the next section (The PET Scanner) the authors shall only briefly mention with appropriate references the modeling of the positron emission tomographic scanner, since this imaging technique is not as widely described in the literature as the CAT scanner. The modeling of the interpreter is not going to be mentioned, since it is a topic that by itself deserves a full paper; see, for example, Pizer [1981]. The thrust of this chapter is on modeling the organs that are being imaged and the matching techniques between the model and the data. The image data is from CAT and PET scans. Although the authors believe that their techniques are applicable to any organ of the human body, the examples are only from the brain

  6. Development of a computerized tomographic system based on the FAN-BEAM technique

    International Nuclear Information System (INIS)

    Junqueira, M.M.; Santos, C.A.C.; Borges, J.C.

    1986-01-01

    The Nuclear Instrumentation Laboratory, at COPPE/UFRJ, concentrates its researches in the development of computerized tomographic systems, looking for applications in industrial and medical non destructive analysing techniques. In this work we have projected and constructed a tomographic prototype, based on the FAN-BEAM technique for irradiating the object under analysis. An algorithm previously developed to analyse parallel beams, was modified and adapted to the FAN-BEAM geometry. (Author) [pt

  7. Computed tomographic characteristics of collateral venous pathways in dogs with caudal vena cava obstruction.

    Science.gov (United States)

    Specchi, Swan; d'Anjou, Marc-André; Carmel, Eric Norman; Bertolini, Giovanna

    2014-01-01

    Collateral venous pathways develop in dogs with obstruction or increased blood flow resistance at any level of the caudal vena cava in order to maintain venous drainage to the right atrium. The purpose of this retrospective study was to describe the sites, causes of obstruction, and configurations of venous collateral pathways for a group of dogs with caudal vena cava obstruction. Computed tomography databases from two veterinary hospitals were searched for dogs with a diagnosis of caudal vena cava obstruction and multidetector row computed tomographic angiographic (CTA) scans that included the entire caudal vena cava. Images for each included dog were retrieved and collateral venous pathways were characterized using image postprocessing and a classification system previously reported for humans. A total of nine dogs met inclusion criteria and four major collateral venous pathways were identified: deep (n = 2), portal (n = 2), intermediate (n = 7), and superficial (n = 5). More than one collateral venous pathway was present in 5 dogs. An alternative pathway consisting of renal subcapsular collateral veins, arising mainly from the caudal pole of both kidneys, was found in three dogs. In conclusion, findings indicated that collateral venous pathway patterns similar to those described in humans are also present in dogs with caudal vena cava obstruction. These collateral pathways need to be distinguished from other vascular anomalies in dogs. Postprocessing of multidetector-row CTA images allowed delineation of the course of these complicated venous pathways and may be a helpful adjunct for treatment planning in future cases. © 2014 American College of Veterinary Radiology.

  8. Analysis and databasing software for integrated tomographic gamma scanner (TGS) and passive-active neutron (PAN) assay systems

    International Nuclear Information System (INIS)

    Estep, R.J.; Melton, S.G.; Buenafe, C.

    2000-01-01

    The CTEN-FIT program, written for Windows 9x/NT in C++,performs databasing and analysis of combined thermal/epithermal neutron (CTEN) passive and active neutron assay data and integrates that with isotopics results and gamma-ray data from methods such as tomographic gamma scanning (TGS). The binary database is reflected in a companion Excel database that allows extensive customization via Visual Basic for Applications macros. Automated analysis options make the analysis of the data transparent to the assay system operator. Various record browsers and information displays simplify record keeping tasks

  9. X-ray Tomographic Analysis of Porosity Distributions in Gas Diffusion Layers of Proton Exchange Membrane Fuel Cells

    International Nuclear Information System (INIS)

    Odaya, S.; Phillips, R.K.; Sharma, Y.; Bellerive, J.; Phillion, A.B.; Hoorfar, M.

    2015-01-01

    This paper describes a method to characterize the structure of polytetrafluoroethylene (PTFE) treated gas diffusion layers (GDLs) with and without microporous layers (MPLs) using 3D X-ray micro computed tomographic (μCT) microscopy. In this work, the structure of single and dual layer GDLs is evaluated via μCT for various GDL samples (such as Toray TGP-H-060 and AvCarb EP40) loaded with different MPLs. A new method is presented for separating, or segmenting, the various phases of the GDL, i.e., void space, carbon fiber (including binder and PTFE), and MPL. Through analysis, it was found that the variation in bulk porosity and the average pore diameter of the GDLs depends highly on the GDL series manufacturing and treatment processes. Using advanced image analysis techniques, routines were developed to accurately segment the GDL fibers (including binder/PTFE) and the MPL. The percentage of the intruding MPL material into the carbon fiber paper as a function of the GDL thickness was successfully found for dual layer GDLs, with varying PTFE content and areal weight loading in the MPL. This analysis provides invaluable insight into the physical microstructure of paper-based GDLs, emphasizing the heterogeneous porosity distribution of single layer GDLs and the interaction of the MPL with the carbon fiber paper of dual layer GDLs

  10. Computed tomographic findings and treatment of a bull with pituitary gland abscess.

    Science.gov (United States)

    Braun, Ueli; Malbon, Alexandra; Kochan, Manon; Riond, Barbara; Janett, Fredi; Iten, Cornelia; Dennler, Matthias

    2017-01-13

    In cattle, the prognosis of brain abscess is unfavourable and treatment is therefore not recommended. To the knowledge of the authors, there has been no report of successful treatment of a brain abscess in cattle.This report describes the clinical, computed tomographic and postmortem findings in a Holstein-Friesian bull with a hypophyseal abscess. The main clinical findings were generalised ataxia, ptyalism, prolapse of the tongue, dropped jaw, dysphagia, head tilt and unilateral ptosis. Cerebrospinal fluid evaluation revealed 2437 leukocytes/µl and severe pleocytosis. CT examination of the head showed a cavitary lesion consistent with an abscess in the hypophysis. Treatment consisted of gentamicin and flunixin meglumine for 3 days and amoxicillin for 40 days. The neurological signs resolved within 8 days of the start of treatment. The bull was slaughtered 11 months later because of infertility, and a postmortem examination was carried out. Histologically, a mild chronic non suppurative meningoencephalitis restricted to the ventral diencephalon was diagnosed. In addition, there was mild to moderate multifocal chronic lymphoplasmacytic hypophysitis with mild multifocal fibrosis. This case report stresses the significance of CT in confirming the clinical and laboratory diagnosis of central nervous system disorders in cattle and for localising brain lesions. Treatment of the brain abscess resulted, with respect to the central nervous disorder, in a successful outcome and was encouraging considering that most cases have an unfavourable prognosis.

  11. Computed tomographic features of the bony canal of the cochlear nerve in pediatric patients with unilateral sensorineural hearing loss

    International Nuclear Information System (INIS)

    Kono, Tatsuo

    2008-01-01

    The aim of this study was to evaluate the diameters of the various bony canals of the inner ear in patients with sensorineural hearing loss (SNHL) and establish criteria for detecting hypoplasia of the bony canal of the cochlear nerve. Measurements obtained in 118 patients without inner ear malformations among 160 patients with unilateral SNHL were analyzed. The diameters of the internal auditory canal and the bony canals of the cochlear, vestibular, and facial nerves were measured on transverse or coronal computed tomographic images. Mean values (±standard deviation (SD)) were compared between the affected and unaffected ears, and statistical analysis was done. The diameter of the bony canal of the cochlear nerve was significantly smaller in affected ears than in unaffected ears (P<0.01). The affected ears could be divided into groups with (72 ears) and without (46 ears) bony canal stenosis. Most (60%) of the patients with unilateral SNHL showed a significant difference in the diameters of the bony canals of the cochlear nerve between the affected and unaffected sides; moreover, the mean value was significantly smaller in affected ears. The diameter of <1.7 mm on transverse images or <1.8 mm on coronal images suggests hypoplasia. (author)

  12. Computational anthropomorphic phantoms for radiation protection dosimetry: evolution and prospects

    International Nuclear Information System (INIS)

    Lee, Choonsik; Lee, Jaiki

    2006-01-01

    Computational anthropomorphic phantoms are computer models of human anatomy used in the calculation of radiation dose distribution in the human body upon exposure to a radiation source. Depending on the manner to represent human anatomy, they are categorized into two classes: stylized and tomographic phantoms. Stylized phantoms, which have mainly been developed at the Oak Ridge National Laboratory (ORNL), describe human anatomy by using simple mathematical equations of analytical geometry. Several improved stylized phantoms such as male and female adults, pediatric series, and enhanced organ models have been developed following the first hermaphrodite adult stylized phantom, Medical Internal Radiation Dose (MIRD)-5 phantom. Although stylized phantoms have significantly contributed to dosimetry calculation, they provide only approximations of the true anatomical features of the human body and the resulting organ dose distribution. An alternative class of computational phantom, the tomographic phantom, is based upon three-dimensional imaging techniques such as Magnetic Resonance (MR) imaging and Computed Tomography (CT). The tomographic phantoms represent the human anatomy with a large number of voxels that are assigned tissue type and organ identity. To date, a total of around 30 tomographic phantoms including male and female adults, pediatric phantoms, and even a pregnant female, have been developed and utilized for realistic radiation dosimetry calculation. They are based on MRI/CT images or sectional color photos from patients, volunteers or cadavers. Several investigators have compared tomographic phantoms with stylized phantoms, and demonstrated the superiority of tomographic phantoms in terms of realistic anatomy and dosimetry calculation. This paper summarizes the history and current status of both stylized and tomographic phantoms, including Korean computational phantoms. Advantages, limitations, and future prospects are also discussed

  13. Automated angular and translational tomographic alignment and application to phase-contrast imaging

    DEFF Research Database (Denmark)

    Cunha Ramos, Tiago Joao; Jørgensen, Jakob Sauer; Andreasen, Jens Wenzel

    2017-01-01

    X-ray computerized tomography (CT) is a 3D imaging technique that makes use of x-ray illumination and image reconstruction techniques to reproduce the internal cross-sections of a sample. Tomographic projection data usually require an initial relative alignment or knowledge of the exact object po...... improvement in the reconstruction resolution. A MATLAB implementation is made publicly available and will allow robust analysis of large volumes of phase-contrast tomography data.......X-ray computerized tomography (CT) is a 3D imaging technique that makes use of x-ray illumination and image reconstruction techniques to reproduce the internal cross-sections of a sample. Tomographic projection data usually require an initial relative alignment or knowledge of the exact object...... reconstruction artifacts and limit the attained resolution in the final tomographic reconstruction. Alignment algorithms that require manual interaction impede data analysis with ever-increasing data acquisition rates, supplied by more brilliant sources. We present in this paper an iterative reconstruction...

  14. Sex Differences in Patients With CAM Deformities With Femoroacetabular Impingement: 3-Dimensional Computed Tomographic Quantification.

    Science.gov (United States)

    Yanke, Adam B; Khair, M Michael; Stanley, Robert; Walton, David; Lee, Simon; Bush-Joseph, Charles A; Espinoza Orías, Alejandro; Espinosa Orias, Alejandro A; Inoue, Nozomu; Nho, Shane J

    2015-12-01

    To determine if significant differences exist between male and female CAM deformities using quantitative 3-dimensional (3D) volume and location analysis. Retrospective analysis of preoperative computed tomographic (CT) scans for 138 femurs (69 from male patients and 69 from female patients) diagnosed with impingement from November 2009 to November 2011 was completed. Those patients who presented with hip complaints and had a history, physical examination (limited range of motion, positive impingement signs), plain radiographs (anteroposterior pelvis, 90° Dunn view, false profile view), and magnetic resonance images consistent with femoroacetabular impingement (FAI) and in whom a minimum of 6 months of conservative therapy (oral anti-inflammatory agents, physical therapy, and activity modification) had failed were indicated for arthroscopic surgery and had a preoperative CT scan. Scans were segmented, converted to point cloud data, and analyzed with a custom-written computer program. Analysis included mean CAM height and volume, head radius, and femoral version. Differences were analyzed using an unpaired t test with significance set at P position ± the 2:51 o'clock position to the 3:28 o'clock position ± the 1:59 o'clock position, with an average span from the 3:06 o'clock position ± the 1:29 o'clock position (male patients, the 11:23 o'clock position ± the 0:46 o'clock position to the 3:05 o'clock position ± the 1:20 o'clock position; female patients, the 11:33 o'clock position ± the 0:37 o'clock position to the 2:27 o'clock position ± the 0:45 o'clock position). There were no differences in the posterior (P = .60) or anterior (P = .14) extent of CAM deformities. However, the span on the clock face of the CAM deformities varied when comparing men with women (male patients, the 3:43 o'clock position ± the 1:29 o'clock position; female patients, the 2:54 o'clock position ± the 1:09 o'clock position; P = .02). Our data show that female CAM deformities

  15. Chest Computed Tomographic Image Screening for Cystic Lung Diseases in Patients with Spontaneous Pneumothorax Is Cost Effective.

    Science.gov (United States)

    Gupta, Nishant; Langenderfer, Dale; McCormack, Francis X; Schauer, Daniel P; Eckman, Mark H

    2017-01-01

    Patients without a known history of lung disease presenting with a spontaneous pneumothorax are generally diagnosed as having primary spontaneous pneumothorax. However, occult diffuse cystic lung diseases such as Birt-Hogg-Dubé syndrome (BHD), lymphangioleiomyomatosis (LAM), and pulmonary Langerhans cell histiocytosis (PLCH) can also first present with a spontaneous pneumothorax, and their early identification by high-resolution computed tomographic (HRCT) chest imaging has implications for subsequent management. The objective of our study was to evaluate the cost-effectiveness of HRCT chest imaging to facilitate early diagnosis of LAM, BHD, and PLCH. We constructed a Markov state-transition model to assess the cost-effectiveness of screening HRCT to facilitate early diagnosis of diffuse cystic lung diseases in patients presenting with an apparent primary spontaneous pneumothorax. Baseline data for prevalence of BHD, LAM, and PLCH and rates of recurrent pneumothoraces in each of these diseases were derived from the literature. Costs were extracted from 2014 Medicare data. We compared a strategy of HRCT screening followed by pleurodesis in patients with LAM, BHD, or PLCH versus conventional management with no HRCT screening. In our base case analysis, screening for the presence of BHD, LAM, or PLCH in patients presenting with a spontaneous pneumothorax was cost effective, with a marginal cost-effectiveness ratio of $1,427 per quality-adjusted life-year gained. Sensitivity analysis showed that screening HRCT remained cost effective for diffuse cystic lung diseases prevalence as low as 0.01%. HRCT image screening for BHD, LAM, and PLCH in patients with apparent primary spontaneous pneumothorax is cost effective. Clinicians should consider performing a screening HRCT in patients presenting with apparent primary spontaneous pneumothorax.

  16. Random signal tomographical analysis of two-phase flow

    International Nuclear Information System (INIS)

    Han, P.; Wesser, U.

    1990-01-01

    This paper reports on radiation tomography which is a useful tool for studying the internal structures of two-phase flow. However, general tomography analysis gives only time-averaged results, hence much information is lost. As a result, it is sometimes difficult to identify the flow regime; for example, the time-averaged picture does not significantly change as an annual flow develops from a slug flow. A two-phase flow diagnostic technique based on random signal tomographical analysis is developed. It extracts more information by studying the statistical variation of the measured signal with time. Local statistical parameters, including mean value, variance, skewness and flatness etc., are reconstructed from the information obtained by a general tomography technique. More important information are provided by the results. Not only the void fraction can be easily calculated, but also the flow pattern can be identified more objectively and more accurately. The experimental setup is introduced. It consisted of a two-phase flow loop, an X-ray system, a fan-like five-beam detector system and a signal acquisition and processing system. In the experiment, for both horizontal and vertical test sections (aluminum and steel tube with Di/Do = 40/45 mm), different flow situations are realized by independently adjusting air and water mass flow. Through a glass tube connected with the test section, some typical flow patterns are visualized and used for comparing with the reconstruction results

  17. 3D Printing of Plant Golgi Stacks from Their Electron Tomographic Models.

    Science.gov (United States)

    Mai, Keith Ka Ki; Kang, Madison J; Kang, Byung-Ho

    2017-01-01

    Three-dimensional (3D) printing is an effective tool for preparing tangible 3D models from computer visualizations to assist in scientific research and education. With the recent popularization of 3D printing processes, it is now possible for individual laboratories to convert their scientific data into a physical form suitable for presentation or teaching purposes. Electron tomography is an electron microscopy method by which 3D structures of subcellular organelles or macromolecular complexes are determined at nanometer-level resolutions. Electron tomography analyses have revealed the convoluted membrane architectures of Golgi stacks, chloroplasts, and mitochondria. But the intricacy of their 3D organizations is difficult to grasp from tomographic models illustrated on computer screens. Despite the rapid development of 3D printing technologies, production of organelle models based on experimental data with 3D printing has rarely been documented. In this chapter, we present a simple guide to creating 3D prints of electron tomographic models of plant Golgi stacks using the two most accessible 3D printing technologies.

  18. Differential diagnosis of solitary pulmonary inflammatory lesions and peripheral lung cancers with contrast-enhanced computed tomograph

    Energy Technology Data Exchange (ETDEWEB)

    Chu, Zhi-gang; Sheng, Bo; Liu, Meng-qi; Lv, Fa-jin; Li, Qi; Ouyang, Yu, E-mail: cyscitg@163.com [Hospital of Chongqing Medical University, Department of Radiology, Chongqing (China)

    2016-10-15

    Objectives: To clarify differences between solitary pulmonary inflammatory lesions and peripheral lung cancers with contrast-enhanced computed tomography. Methods: In total, 64 and 132 patients with solitary pulmonary inflammatory masses/nodules and peripheral lung cancers, respectively, were enrolled in this study. Their computed tomographic findings were summarized and compared retrospectively. Results: Compared with the peripheral lung cancers, the inflammatory lesions were located closer to the pleura (p<0.0001). The majority of the inflammatory lesions were patchy and oval-shaped (82.8%), whereas most of the tumors were lobulated (82.6%). Almost all the inflammatory cases were unclear (93.8%), whereas most of the tumors had speculated margins (72.7%). Computed tomography values were significantly higher for the inflammatory lesions than for the cancers (p<0.0001). More than half of the inflammatory lesions had defined necrosis (59.3%). Furthermore, 49.2% of the cancers enhanced inhomogeneously, but only 24.6% had ill-defined necrosis or cavities. The peripheral zones of 98.4% of the inflammatory lesions and 72.7% of the tumors were unclear, with peripheral scattered patches (92.2%) and beam-shaped opacity (66.7%) being the most common findings, respectively. Adjacent pleural thickening was more frequent for the inflammatory lesions than the cancers (95.3% vs. 21.1%, p<0.0001), whereas pleural indentation was found in 67.4% of the subjects with cancer. In addition, hilar (p=0.034) and mediastinal (p=0.003) lymphadenopathy were more commonly detected in the cancers than in the inflammatory cases. Conclusions: Contrast-enhanced computed tomography findings for pulmonary inflammatory lesions and peripheral lung cancers were significantly different in many aspects. Developing a comprehensive understanding of these differences is helpful for directing their management. (author)

  19. Tomographic analysis of CBF in cerebral infarction

    International Nuclear Information System (INIS)

    Segawa, Hiromu; Kimura, Kazumoto; Ueda, Yuichi; Nagai, Masakatsu; Yoshimasu, Norio.

    1983-01-01

    Cerebral perfusion was examined in various types of occlusive disease by computed tomographic CBF method. The method utilized has several advantages over conventional studies using isotope, providing high resolution images in a direct relation to CT anatomy. Ten representative cases were presented from 25 consective cases of occlusive disease studied by this method. The method included inhalation of 40 to 60% xenon with serial CT scanning for 25 min. K (build-up rate), lambda (partition coefficient) and CBF values were calculated from ΔHU for each pixel and ΔXe in expired air, based on Fick's principle, and displayed on CRT as K-, lambda- and CBF-map separately. CBF for gray matter of normal control was 82 +- 11 ml/100 gm/min and that for white matter was 24 +- 5 ml/100 gm/min. The ischemic threshold for gray matter appeared to be approximately 20 ml/100 gm/min, as blood flow in focus of complete infarction was below this level. Blood flow between 20 - 30 ml/ 100 gm/min caused some change on CT, such as localized atrophy, cortical thinning, loss of distinction between gray and white matter and decreased or increased density, which were considered to be compatible with pathological changes of laminar necrosis or gliosis with neuronal loss. In a case with occlusion of middle cerebral artery with subsequent recanalization, causing hemorrhagic infarct, hyperemia was observed in the infarcted cortex that was enhanced by iodine. Periventricular lucency observed in two cases, where blood flow was decreased below threshold, could be classified as ''watershed infarction'' mainly involving white matter. In moyamoya disease, blood flow in the anterior circulation was decreased near ischemic level, whereas that in basal ganglia and territory of posterior cerebral artery was fairly preserved, which was compatible with general angiographic finding of this disease. (author)

  20. Detectability of Middle Mesial Root Canal Orifices by Troughing Technique in Mandibular Molars: A Micro-computed Tomographic Study.

    Science.gov (United States)

    Keleş, Ali; Keskin, Cangül

    2017-08-01

    The objective of the present study was to measure the orifice depth of middle mesial canals (MMCs) and evaluate the detectability of orifices using troughing preparation. For this study, 85 mandibular molar teeth with MMCs were selected from the scanned micro-computed tomographic images. The MMCs were categorized, and the distances between the MMC orifices and the cementoenamel junctions (CEJ) were recorded as the depth of the orifice. Data were evaluated with frequency analysis and a chi-square test using SPSS (SPSS Inc, Chicago, IL), and the results indicated a 5% significance level. It was found that 77.41% of the MMC orifices were at the CEJ level, whereas 5.38% and 9.69% of the MMC orifices were detectable within 1-mm and 2-mm depths from the CEJ, respectively. Of the specimens, 7.52% had MMC orifices deeper than 2 mm from the CEJ. Confluent anatomy was the most frequent configuration. No significant relation was detected between the orifice depth and MMC configuration (P > .05). It was concluded that 77.41% of the specimens did not require troughing preparation, the remaining 15.07% would require troughing, and 7.52% could not be accessed even with the troughing preparation. Copyright © 2017 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  1. Variation in Location of the Mandibular Foramen/Inferior Alveolar Nerve Complex Given Anatomic Landmarks Using Cone-beam Computed Tomographic Scans.

    Science.gov (United States)

    Blacher, Jonathan; Van DaHuvel, Scott; Parashar, Vijay; Mitchell, John C

    2016-03-01

    The inferior alveolar nerve (IAN) injection is 1 of the most commonly administered and useful injections in the field of dentistry. Practitioners use intraoral anatomic landmarks, which vary greatly among patients. The objective of this study was to assist practitioners by identifying a range of normal variability within certain landmarks used in delivering IAN anesthesia. A total of 203 randomly selected retrospective cone-beam computed tomographic scans were obtained from the Midwestern University Dental Institute cone-beam computed tomographic database. InVivoDental5.0 volumetric imaging software (Anatomage, San Jose, CA) was used to measure 2 important parameters used in locating the mandibular foramen (MF)/IAN complex: (1) the angle from the contralateral premolar contact area to the MF and (2) the distance above the mandibular occlusal plane to the center of the MF. The variation of these measurements was compared with established reference values and statistically analyzed using a 1-sample t test. The angle from the contralateral premolar contact area to the MF for the right and left sides was 42.99° and 42.57°, respectively. The angulations varied significantly from the reference value of 45° (P < .001). The minimum height above the mandibular occlusal plane for the right and left sides was 9.85 mm and 9.81 mm, respectively. The heights varied significantly from the minimum reference value of 6 mm but not the maximum reference value of 10 mm (P < .001). Orienting the syringe barrel at an angulation slightly less than 45° and significantly higher than 6 mm above the mandibular occlusal plane can aid in successfully administering anesthesia to the MF/IAN complex. Copyright © 2016 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  2. Tomographical properties of uniformly redundant arrays

    International Nuclear Information System (INIS)

    Cannon, T.M.; Fenimore, E.E.

    1978-01-01

    Recent work in coded aperture imaging has shown that the uniformly redundant array (URA) can image distant planar radioactive sources with no artifacts. The performance of two URA apertures when used in a close-up tomographic imaging system is investigated. It is shown that a URA based on m sequences is superior to one based on quadratic residues. The m sequence array not only produces less obnoxious artifacts in tomographic imaging, but is also more resilient to some described detrimental effects of close-up imaging. It is shown that in spite of these close-up effects, tomographic depth resolution increases as the source is moved closer to the detector

  3. Abdominal alterations in disseminated paracoccidioidomycosis: computed tomography findings

    Energy Technology Data Exchange (ETDEWEB)

    Vermelho, Marli Batista Fernandes; Correia, Ademir Silva; Michailowsky, Tania Cibele de Almeida; Suzart, Elizete Kazumi Kuniyoshi; Ibanes, Aline Santos; Almeida, Lanamar Aparecida; Khoury, Zarifa; Barba, Mario Flores, E-mail: marlivermelho@globo.com [Instituto de Infectologia Emilio Ribas (IIER), Sao Paulo, SP (Brazil)

    2015-03-15

    Objective: to evaluate the incidence and spectrum of abdominal computed tomography imaging findings in patients with paracoccidioidomycosis. Materials and methods: retrospective analysis of abdominal computed tomography images of 26 patients with disseminated paracoccidioidomycosis. Results: abnormal abdominal tomographic findings were observed in 18 patients (69.2%), while no significant finding was observed in the other 8 (30.8%) patients. Conclusion: computed tomography has demonstrated to play a relevant role in the screening and detection of abdominal abnormalities in patients with disseminated paracoccidioidomycosis. (author)

  4. A maximum entropy reconstruction technique for tomographic particle image velocimetry

    International Nuclear Information System (INIS)

    Bilsky, A V; Lozhkin, V A; Markovich, D M; Tokarev, M P

    2013-01-01

    This paper studies a novel approach for reducing tomographic PIV computational complexity. The proposed approach is an algebraic reconstruction technique, termed MENT (maximum entropy). This technique computes the three-dimensional light intensity distribution several times faster than SMART, using at least ten times less memory. Additionally, the reconstruction quality remains nearly the same as with SMART. This paper presents the theoretical computation performance comparison for MENT, SMART and MART, followed by validation using synthetic particle images. Both the theoretical assessment and validation of synthetic images demonstrate significant computational time reduction. The data processing accuracy of MENT was compared to that of SMART in a slot jet experiment. A comparison of the average velocity profiles shows a high level of agreement between the results obtained with MENT and those obtained with SMART. (paper)

  5. A morphological study of the mandibular molar region using reconstructed helical computed tomographic images

    International Nuclear Information System (INIS)

    Tsuno, Hiroaki; Noguchi, Makoto; Noguchi, Akira; Yoshida, Keiko; Tachinami, Yasuharu

    2010-01-01

    This study investigated the morphological variance in the mandibular molar region using reconstructed helical computed tomographic (CT) images. In addition, we discuss the necessity of CT scanning as part of the preoperative assessment process for dental implantation, by comparing the results with the findings of panoramic radiography. Sixty patients examined using CT as part of the preoperative assessment for dental implantation were analyzed. Reconstructed CT images were used to evaluate the bone quality and cross-sectional bone morphology of the mandibular molar region. The mandibular cortical index (MCI) and X-ray density ratio of this region were assessed using panoramic radiography in order to analyze the correlation between the findings of the CT images and panoramic radiography. CT images showed that there was a decrease in bone quality in cases with high MCI. Cross-sectional CT images revealed that the undercuts on the lingual side in the highly radiolucent areas in the basal portion were more frequent than those in the alveolar portion. This study showed that three-dimensional reconstructed CT images can help to detect variances in mandibular morphology that might be missed by panoramic radiography. In conclusion, it is suggested that CT should be included as an important examination tool before dental implantation. (author)

  6. Image-guided microneurosurgical management of small cerebral arteriovenous malformations: the value of navigated computed tomographic angiography

    International Nuclear Information System (INIS)

    Coenen, V.A.; Reinges, M.H.T.; Gilsbach, J.M.; Rohde, V.; Dammert, S.; Mull, M.

    2005-01-01

    In small arteriovenous malformations (AVM) with large hematomas, surgery remains the main therapeutic option. However, intraoperative identification of the AVM, feeders, and draining veins could be difficult in the environment of substantial intracerebral blood. In those selected cases, we use navigated computed tomographic angiography (CTA) for the microneurosurgical management. It is our objective to report our initial experiences. Prior to operation a conventional CTA with superficial skin fiducials placed on a patient's head was acquired for diagnostic and neuronavigation purposes. Image data were transferred to a neuronavigation device with integrated volume rendering capacities which allows a three-dimensional reconstruction of the vascular tree and the AVM to be created. In all patients the AVM was removed successfully after having been localized with CTA-based neuronavigation. Navigated CTA is helpful for the operative management of small AVMs with large hematomas. The technique allows feeding arteries to be distinguished from draining veins thereby allowing the nidus of the AVM to be identified despite the presence of substantial intracerebral blood. CTA can be easily implemented into commercial neuronavigation systems. (orig.)

  7. Tomographic scanning apparatus

    International Nuclear Information System (INIS)

    1981-01-01

    This patent specification relates to a tomographic scanning apparatus using a fan beam and digital output signal, and particularly to the design of the gas-pressurized ionization detection system. (U.K.)

  8. Four-dimensional computed tomographic analysis of esophageal mobility during normal respiration

    NARCIS (Netherlands)

    Dieleman, Edith M. T.; Senan, Suresh; Vincent, Andrew; Lagerwaard, Frank J.; Slotman, Ben J.; van Sörnsen de Koste, John R.

    2007-01-01

    BACKGROUND: Chemo-radiotherapy for thoracic tumors can result in high-grade radiation esophagitis. Treatment planning to reduce esophageal irradiation requires organ motion to be accounted for. In this study, esophageal mobility was assessed using four-dimensional computed tomography (4DCT). METHODS

  9. Computed tomographic analysis of calvarial hyperostosis in captive lions.

    Science.gov (United States)

    Gross-Tsubery, Ruth; Chai, Orit; Shilo, Yael; Miara, Limor; Horowitz, Igal H; Shmueli, Ayelet; Aizenberg, Itzhak; Hoffman, Chen; Reifen, Ram; Shamir, Merav H

    2010-01-01

    Osseous malformations in the skull and cervical vertebrae of lions in captivity are believed to be caused by hypovitaminosis A. These often lead to severe neurologic abnormalities and may result in death. We describe the characterization of these abnormalities based on computed tomography (CT). CT images of two affected and three healthy lions were compared with define the normal anatomy of the skull and cervical vertebrae and provide information regarding the aforementioned osseous malformations. Because bone structure is influenced by various factors other than the aforementioned disease, all values were divided by the skull width that was not affected. The calculated ratios were compared and the most pronounced abnormalities in the affected lions were, narrowing of the foramen magnum, thickening of the tentorium osseus cerebelli and thickening of the dorsal arch of the atlas. CT is useful for detection of the calvarial abnormalities in lions and may be useful in further defining this syndrome.

  10. Accuracy of computed tomographic intravenous cholangiography (CT-IVC) with iotroxate in the detection of choledocholithiasis

    International Nuclear Information System (INIS)

    Gibson, Robert N.; Vincent, Janette M.; Speer, Tony; Noack, Keith; Collier, Neil A.

    2005-01-01

    To determine the accuracy of computed tomographic intravenous cholangiography (CT-IVC) for detection of choledocholithiasis. Sixty-five patients undergoing endoscopic retrograde cholangiography (ERC) underwent CT-IVC prior to ERC, using a single detector helical CT following intravenous infusion of 100 ml iotroxate. Patients with bilirubin levels >3 times normal were excluded. ERC was indeterminate in three patients (4.7%) and CT-IVC in four (6.3%). Twenty-three patients had ductal calculi at ERC, and CT-IVC was positive in 22, with two false positives and one false negative: sensitivity 95.6%, specificity 94.3%. Stones were multiple in nine and solitary in 14. Of the 14 solitary stones, ten were ≤5 mm and eight were ≤4 mm. The bilirubin level in positive cases was within normal in 20. Maximum intensity projection (MIP) reformats showed stones in only 27% of cases and surface rendered (SR) reformats in none. CT-IVC is highly accurate for detection of ductal calculi, including single small calculi, with a normal or near normal serum bilirubin. Axial images should be used for interpretation rather than MIP or SR reformats. (orig.)

  11. Emerging tomographic methods within the petroleum industry

    International Nuclear Information System (INIS)

    Johansen, Geir Anton

    2013-01-01

    Since industrial process tomography was introduced as a concept almost two decades ago, the considerable progress within a large variety of sensing modalities has to a large extent been technology driven. Industrial tomography applications may be divided into three categories: 1) Laboratory systems, 2) Field equipment for diagnostics and mapping purposes, and 3) Permanently installed systems. Examples on emerging methods on all categories will be presented, either from R and D at the University of Bergen and/or our industrial partners. Most developments are within the first category, where tomographs are used to provide better understanding of various processes such as pipe flow, separators, mixers and reactors. Here tomographic data is most often used to provide better process knowledge, for reference measurements and validation and development of process models, and finally for development for instruments and process equipment. The requirement here may be either high spatial resolution or high temporal resolution, or combinations of these. Tomographic field measurements are applied to either to inspect processes or equipment on a regular base or at faulty or irregular operation, or to map multicomponent systems such petroleum reservoirs, their structure and the distribution gas, oil and water within them. The latter will only be briefly touched upon here. Tomographic methods are increasingly being used for process and equipment diagnostics. The requirements vary and solutions based on repetition of single measurements, such as in column scanning, to full tomographic systems where there is sufficiently space or access. The third category is tomographic instruments that are permanently installed in situ in a process. These need not provide full tomographic images and instruments with fewer views are often preferred to reduce complexity and increase the instrument reliability. (author)

  12. Computer tomographic phantom

    International Nuclear Information System (INIS)

    Lonn, A.H.R.; Jacobsen, D.R.; Zech, D.J.

    1988-01-01

    A reference phantom for computer tomography employs a flexible member with means for urging the flexible member into contact along the curved surface of the lumbar region of a human patient. In one embodiment, the reference phantom is pre-curved in an arc greater than required. Pressure from the weight of a patient laying upon the reference phantom is effective for straightening out the curvature sufficiently to achieve substantial contact along the lumbar region. The curvature of the reference phantom may be additionally distorted by a resilient pad between the resilient phantom and a table for urging it into contact with the lumbar region. In a second embodiment of the invention, a flexible reference phantom is disposed in a slot in the top of a resilient cushion. The resilient cushion and reference phantom may be enclosed in a flexible container. A partially curved reference phantom in a slot in a resilient cushion is also contemplated. (author)

  13. Tomographic scanning apparatus

    International Nuclear Information System (INIS)

    1981-01-01

    Details are presented of a tomographic scanning apparatus, its rotational assembly, and the control and circuit elements, with particular reference to the amplifier and multiplexing circuits enabling detector signal calibration. (U.K.)

  14. Tomographic reconstruction by using FPSIRT (Fast Particle System Iterative Reconstruction Technique)

    Energy Technology Data Exchange (ETDEWEB)

    Moreira, Icaro Valgueiro M.; Melo, Silvio de Barros; Dantas, Carlos; Lima, Emerson Alexandre; Silva, Ricardo Martins; Cardoso, Halisson Alberdan C., E-mail: ivmm@cin.ufpe.br, E-mail: sbm@cin.ufpe.br, E-mail: rmas@cin.ufpe.br, E-mail: hacc@cin.ufpe.br, E-mail: ccd@ufpe.br, E-mail: eal@cin.ufpe.br [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil)

    2015-07-01

    The PSIRT (Particle System Iterative Reconstruction Technique) is a method of tomographic image reconstruction primarily designed to work with configurations suitable for industrial applications. A particle system is an optimization technique inspired in real physical systems that associates to the reconstructing material a set of particles with certain physical features, subject to a force eld, which can produce movement. The system constantly updates the set of particles by repositioning them in such a way as to approach the equilibrium. The elastic potential along a trajectory is a function of the difference between the attenuation coefficient in the current configuration and the corresponding input data. PSIRT has been successfully used to reconstruct simulated and real objects subject to sets of parallel and fanbeam lines in different angles, representing typical gamma-ray tomographic arrangements. One of PSIRT's limitation was its performance, too slow for real time scenarios. In this work, it is presented a reformulation in PSIRT's computational model, which is able to grant the new algorithm, the FPSIRT - Fast System Iterative Reconstruction Technique, a performance up to 200-time faster than PSIRT's. In this work a comparison of their application to real and simulated data from the HSGT, High Speed Gamma Tomograph, is presented. (author)

  15. Tomographic reconstruction by using FPSIRT (Fast Particle System Iterative Reconstruction Technique)

    International Nuclear Information System (INIS)

    Moreira, Icaro Valgueiro M.; Melo, Silvio de Barros; Dantas, Carlos; Lima, Emerson Alexandre; Silva, Ricardo Martins; Cardoso, Halisson Alberdan C.

    2015-01-01

    The PSIRT (Particle System Iterative Reconstruction Technique) is a method of tomographic image reconstruction primarily designed to work with configurations suitable for industrial applications. A particle system is an optimization technique inspired in real physical systems that associates to the reconstructing material a set of particles with certain physical features, subject to a force eld, which can produce movement. The system constantly updates the set of particles by repositioning them in such a way as to approach the equilibrium. The elastic potential along a trajectory is a function of the difference between the attenuation coefficient in the current configuration and the corresponding input data. PSIRT has been successfully used to reconstruct simulated and real objects subject to sets of parallel and fanbeam lines in different angles, representing typical gamma-ray tomographic arrangements. One of PSIRT's limitation was its performance, too slow for real time scenarios. In this work, it is presented a reformulation in PSIRT's computational model, which is able to grant the new algorithm, the FPSIRT - Fast System Iterative Reconstruction Technique, a performance up to 200-time faster than PSIRT's. In this work a comparison of their application to real and simulated data from the HSGT, High Speed Gamma Tomograph, is presented. (author)

  16. Tomographic scanning apparatus

    International Nuclear Information System (INIS)

    1981-01-01

    Details are given of a tomographic scanning apparatus, with particular reference to a multiplexer slip ring means for receiving output from the detectors and enabling interfeed to the image reconstruction station. (U.K.)

  17. High-resolution computed tomographic findings of Aspergillus infection in lung transplant patients

    International Nuclear Information System (INIS)

    Gazzoni, Fernando Ferreira; Hochhegger, Bruno; Severo, Luiz Carlos; Marchiori, Edson; Pasqualotto, Alessandro; Sartori, Ana Paula Garcia; Schio, Sadi; Camargo, José

    2014-01-01

    Objective: The aim of this study was to assess high-resolution computed tomographic (HRCT) findings at presentation in lung transplant patients diagnosed with pulmonary Aspergillus infection. Materials and methods: We retrospectively reviewed HRCT findings from 23 patients diagnosed with pulmonary aspergillosis. Imaging studies were performed 2–5 days after the onset of symptoms. The patient sample comprised 12 men and 11 women aged 22–59 years (mean age, 43.6 years). All patients had dyspnea, tachypnea, and cough. Diagnoses were established with Platelia Aspergillus enzyme immunoassays for galactomannan antigen detection in bronchoalveolar lavage and recovery of symptoms, and HRCT findings after voriconazole treatment. The HRCT scans were reviewed independently by two observers who reached a consensus decision. Results: The main HRCT pattern, found in 65% (n = 15) of patients, was centrilobular tree-in-bud nodules associated with bronchial thickening. This pattern was described in association with areas of consolidation and ground-glass opacities in 13% (n = 3) of patients. Consolidation and ground-glass opacities were the main pattern in 22% (n = 5) of patients. The pattern of large nodules with and without the halo sign was observed in 13% (n = 3) of patients, and were associated with consolidation and ground-glass opacities in one case. Conclusion: The predominant HRCT findings in lung transplant patients with pulmonary aspergillosis were bilateral bronchial wall thickening and centrilobular opacities with the tree-in-bud pattern. Ground-glass opacities and/or bilateral areas of consolidation were also common findings. Pulmonary nodules with the halo sign were found in only 13% of patients

  18. Effect of Post Space Preparation on Apical Obturation Quality of Teeth Obturated with Different Techniques: A Micro-computed Tomographic Study.

    Science.gov (United States)

    Küçükkaya Eren, Selen; Askerbeyli Örs, Sevinc; Yılmaz, Zeliha

    2017-07-01

    The purpose of this study was to evaluate the obturation quality of root canals filled with different techniques and to determine whether post space preparation had an effect on the quality of apical obturation using micro-computed tomographic (micro-CT) imaging. The root canals of 30 human mandibular premolar teeth were instrumented, and the specimens were divided into 3 groups according to the obturation technique used: cold lateral compaction (CLC), warm vertical compaction (WVC), or single-cone (SC) techniques. The specimens were stored at 37°C and 100% humidity for 1 week. Then, the coronal root filling material was removed in order to create a post space. Micro-CT scans were performed before and after post space preparation for the volumetric analysis of voids and filling materials. Data were analyzed using repeated-measures analysis of variance and Bonferroni tests. The CLC and SC groups showed a significantly greater percentage volume of voids than the WVC group (P space preparation (P > .05). The post space preparation caused a significant increase in the percentage volume of voids in the CLC and SC groups (P space preparation (P > .05). No root fillings were void free. The WVC group presented the best obturation quality. The post space preparation negatively influenced the apical integrity of the filling materials in the CLC and SC groups, whereas it had no significant effect in the WVC group. Copyright © 2017 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  19. Echocardiographic and non-gated computed tomographic findings of intrapericardial tumor and mediastinal tumor adjacent to the heart

    International Nuclear Information System (INIS)

    Ueda, Minoru; Yamada, Nobuyuki; Saito, Daiji; Haraoka, Shoichi; Tanetani, Setsuro.

    1981-01-01

    Echocardiographic and computed tomographic findings of a case of intrapericardial tumor are reported, and two other cases of mediastinal tumor are presented in a discussion of the differential diagnosis of intrapericardial from mediastinal tumors. Case report: A 7-year-old male complained of cough and dyspnea. Cardiomegaly had been pointed out at a mass X-ray examination about a month prior to the admission. Two-dimensional echocardiography revealed a massive anterior pericardial effusion and a fist-sized tumor with cystic structure. The tumor pushed the heart backward at the level of the aortic root. Non-gated computed tomography of the chest disclosed the size and location of the tumor, but failed to clarify the internal structure. The patient underwent successful removal of a tumor, 12 x 10 x 8 cm in size and 350 g in weight, originating from the left atrial wall. Histologically, the tumor was a fibrosarcomatous mesothelioma. Usually, an intrapericardial tumor is easily suspected by echocardiography by the presence of pericardial effusion, although there have been a few reports of intrapericardial tumors without pericardial effusion. Echocardiographic diagnosis of the intrapericardial tumor is difficult in such cases. Identification of the pericardium is necessary to diagnose whether a tumor is intra- or extrapericardial. This identification, however, is not always easy by echocardiography when the ultrasonic beams become tangent to the pericardium. The pericardium between the tumor and the heart could not be identified by echocardiography in our two cases of mediastinal tumor. Computed tomography is helpful in diagnosing the size and location of a mediastinal tumor. (author)

  20. Computed tomographic evaluation of the pancreas

    International Nuclear Information System (INIS)

    Stanley, R.J.; Sagel, S.S.

    1979-01-01

    Analysis of the clinical experience in the evaluation of the pancreas with computed tomography (CT) since October 1975 indicates that it is a reliable, often specific and relatively noninvasive method for the detection of pancreatic neoplasms and the varied manifestations of pancreatitis and its complications. The normal pancreas is clearly imaged in all but the leanest or uncooperative patients. Tumors of pancreas are identified as focal alteration in the size or contour of the gland. Obliteration of contiguous fat planes, areas of necrosis within the tumor, and secondary effects on the uninvolved parts of the pancreas and biliary tree can be identified. CBT has substantially reduced the need for pancreatic angiography, percutaneous transhepatic cholangiography, and endoscopic retrograde pancreatocholangiography at this medical center. Although a definitive comparison of ultrasound and CT has not yet been accomplished, initial experience indicates that a complementary rather than competitive relationship will develop between the two imaging methods. (orig.) 891 MG/orig. 892 MB [de

  1. Computed tomographic-guided iodine-125 interstitial implants for malignant thoracic tumors

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Qiming [The Department of Radiology, First Affiliated Hospital of Fujian Medical University, 20 Chazhong Road, Fuzhou 350005 (China); The Department of Radiology, Second Affiliated Hospital of Fujian Medical University, 34 Zhongshan Bei Road, Quanzhou 362000 (China); Chen, Jin; Chen, Qunlin [The Department of Radiology, First Affiliated Hospital of Fujian Medical University, 20 Chazhong Road, Fuzhou 350005 (China); Lai, Qingquan; Cai, Siqing [The Department of Radiology, Second Affiliated Hospital of Fujian Medical University, 34 Zhongshan Bei Road, Quanzhou 362000 (China); Luo, Kaidong [The Department of Radiology, Longyan Hosptial of Traditional Chinese Medical, 59 Longteng Middle Road, Longyan 364000 (China); Lin, Zhengyu, E-mail: linsinlan@yahoo.com.cn [The Department of Radiology, First Affiliated Hospital of Fujian Medical University, 20 Chazhong Road, Fuzhou 350005 (China)

    2013-11-01

    Purpose: To evaluate the feasibility and efficacy of percutaneous interstitial brachytherapy using iodine-125 ({sup 125}I) radioactive seeds under computed tomographic (CT) guidance for malignant thoracic tumors. Materials and methods: Forty-one patients (34 males, 7 females; 18–90 years; mean, 63.7 years) with 77 lesions (3 in the mediastinum, 7 in the chest wall, 67 in the lung) underwent percutaneous interstitial implantation of {sup 125}I radioactive seeds under CT guidance. A treatment planning system (TPS) was employed to calculate the number and distribution of seeds preoperatively. An 18-G needle was inserted into the lesions under CT guidance and send the seeds according to TPS. Two patients with mediastinal lesions undergoing seed implantation received an artificial pneumothorax. One patient with lung carcinoma adjacent to the anterior mediastinum underwent seed implantation through the sternum. Follow-up CT was done every 2 months postoperatively. Results: The procedure was successful in all patients. No major procedure-associated death occurred. The mean duration of follow-up was 19.4 ± 1.3 months (3–49 months). A complete response (CR) was seen in 49 lesions (63.6%), partial response (PR) in 9 lesions (11.7%), stable disease (SD) in 12 lesions (12.8%), and progressive disease (PD) in 7 lesions (7.4%). The overall response rate (CR + PR) was 75.3%; the local control rate (CR + PR + SD) was 90.9%. The 1-, 2- and 3-year progression-free rates for local tumors were 91%, 88% and 88%, respectively. The 1-, 2- and 3-year survival rates were 87%, 74% and 68%, respectively. Conclusion: Implantation of CT-guided {sup 125}I seeds is feasible and effective for patients with malignant thoracic tumors.

  2. Tomographic scanning apparatus

    International Nuclear Information System (INIS)

    1981-01-01

    This patent specification describes a tomographic scanning apparatus, with particular reference to the adjustable fan beam and its collimator system, together with the facility for taking a conventional x-radiograph without moving the patient. (U.K.)

  3. A new algorithm for γ-ray tomographic imaging using a scintillation camera

    International Nuclear Information System (INIS)

    Terajima, Hirokatsu; Nakajima, Masato; Itoh, Takashi.

    1979-01-01

    The gamma ray tomographic imaging giving 3-dimensional distribution of RI in human bodies is being actively investigated for the reason that the conventional images are of 2-dimensional projection, but it is not yet employed practically, because there are some problems in the tomographic image quality obtained. One of the methods is a technique to determine the radioisotope distribution on each tomographic plane by placing a planar detector in parallel with the assumed tomographic planes and by processing the 2-dimensional radioisotope projection images thus obtained. It does not require the repetition of reconstructive algorithm. The authors have proposed the algorithm for this method, and have carried out the experiments to verify the propriety of the algorithm. Radioisotope phantom is composed of the overlapping acrylic cubic vessels of 30 mm sides containing radioisotopes arranged 2-dimensionally in each layer, and the multi-pinhole shutter array is used as the collimator. The projection image of radioisotope distribution on the scintillator face is converted into the digital imaging data sampled in 2-dimensional space of 64 x 64 with the mini-computer. Among the probable causes to affect the reconstructed image quality, statistical fluctuation, absorption of gamma ray and the shape of aperture for the collimator are discussed. These indicate that this method is more effective than the conventional methods, and can be the effective technique for medical diagnosis and therapy, because this is a technique to determine 3-dimensional distribution of RI by utilizing existing equipments. (Wakatsuki, Y.)

  4. Axial tomographic scanner

    International Nuclear Information System (INIS)

    1976-01-01

    An axial tomographic system is described comprising axial tomographic means for collecting sets of data corresponding to the transmission or absorption of a number of beams of penetrating radiation through a planar slice of an object. It includes means to locate an object to be analyzed, a source and detector for directing one or more beams of penetrating radiation through the object from the source to the detector, and means to rotate (and optionally translate) the source as well as means to process the collected sets of data. Data collection, data processing, and data display can each be conducted independently of each other. An additional advantage of the system described is that the raw data (i.e., the originally collected data) are not destroyed by the data processing but instead are retained intact for further reference or use, if needed

  5. Analysis of bite marks in foodstuffs by computer tomography (cone beam CT)--3D reconstruction.

    Science.gov (United States)

    Marques, Jeidson; Musse, Jamilly; Caetano, Catarina; Corte-Real, Francisco; Corte-Real, Ana Teresa

    2013-12-01

    The use of three-dimensional (3D) analysis of forensic evidence is highlighted in comparison with traditional methods. This three-dimensional analysis is based on the registration of the surface from a bitten object. The authors propose to use Cone Beam Computed Tomography (CBCT), which is used in dental practice, in order to study the surface and interior of bitten objects and dental casts of suspects. In this study, CBCT is applied to the analysis of bite marks in foodstuffs, which may be found in a forensic case scenario. 6 different types of foodstuffs were used: chocolate, cheese, apple, chewing gum, pizza and tart (flaky pastry and custard). The food was bitten into and dental casts of the possible suspects were made. The dental casts and bitten objects were registered using an x-ray source and the CBCT equipment iCAT® (Pennsylvania, EUA). The software InVivo5® (Anatomage Inc, EUA) was used to visualize and analyze the tomographic slices and 3D reconstructions of the objects. For each material an estimate of its density was assessed by two methods: HU values and specific gravity. All the used materials were successfully reconstructed as good quality 3D images. The relative densities of the materials in study were compared. Amongst the foodstuffs, the chocolate had the highest density (median value 100.5 HU and 1,36 g/cm(3)), while the pizza showed to have the lowest (median value -775 HU and 0,39 g/cm(3)), on both scales. Through tomographic slices and three-dimensional reconstructions it was possible to perform the metric analysis of the bite marks in all the foodstuffs, except for the pizza. These measurements could also be obtained from the dental casts. The depth of the bite mark was also successfully determined in all the foodstuffs except for the pizza. Cone Beam Computed Tomography has the potential to become an important tool for forensic sciences, namely for the registration and analysis of bite marks in foodstuffs that may be found in a crime

  6. Typical computer tomographic findings in neurofibromatosis

    International Nuclear Information System (INIS)

    Allgayer, B.; Reiser, M.; Kramann, B.

    1984-01-01

    Three pateints with neurofibromatosis (Recklinghausen's disease) were examined by computer tomography. In this way, the exact extent and localisation of the neurofibromatous tumours could be demonstrated. In one patient, CT provided evidence of malignant change; this was verified histologically. The appearances of neurofibromatosis associated with elephantiasis is described. In each patient, treatment was significantly influenced by computer tomography. (orig.) [de

  7. Typical computer tomographic findings in neurofibromatosis

    Energy Technology Data Exchange (ETDEWEB)

    Allgayer, B.; Reiser, M.; Kramann, B.

    1984-06-01

    Three pateints with neurofibromatosis (Recklinghausen's disease) were examined by computer tomography. In this way, the exact extent and localisation of the neurofibromatous tumours could be demonstrated. In one patient, CT provided evidence of malignant change; this was verified histologically. The appearances of neurofibromatosis associated with elephantiasis is described. In each patient, treatment was significantly influenced by computer tomography.

  8. Tomographic visualization of stress corrosion cracks in tubing

    International Nuclear Information System (INIS)

    Morris, R.A.; Kruger, R.P.; Wecksung, G.W.

    1979-06-01

    A feasibility study was conducted to determine the possibility of detecting and sizing cracks in reactor cooling water tubes using tomographic techniques. Due to time and financial constraints, only one tomographic reconstruction using the best technique available was made. The results indicate that tomographic reconstructions can, in fact, detect cracks in the tubing and might possibly be capable of measuring the depth of the cracks. Limits of detectability and sensitivity have not been determined but should be investigated in any future work

  9. Computed tomography and three-dimensional imaging

    International Nuclear Information System (INIS)

    Harris, L.D.; Ritman, E.L.; Robb, R.A.

    1987-01-01

    Presented here is a brief introduction to two-, three-, and four-dimensional computed tomography. More detailed descriptions of the mathematics of reconstruction and of CT scanner operation are presented elsewhere. The complementary tomographic imaging methods of single-photon-emission tomography (SPECT) positron-emission tomography (PET), nuclear magnetic resonance (NMR) imaging, ulltrasound sector scanning, and ulltrasound computer-assisted tomography [UCAT] are only named here. Each imaging modality ''probes'' the body with a different energy form, yielding unique and useful information about tomographic sections through the body

  10. Advanced Ultrasonic Tomograph of Children's Bones

    Science.gov (United States)

    Lasaygues, Philippe; Lefebvre, Jean-Pierre; Guillermin, Régine; Kaftandjian, Valérie; Berteau, Jean-Philippe; Pithioux, Martine; Petit, Philippe

    This study deals with the development of an experimental device for performing ultrasonic computed tomography (UCT) on bone in pediatric degrees. The children's bone tomographs obtained in this study, were based on the use of a multiplexed 2-D ring antenna (1 MHz and 3 MHz) designed for performing electronic and mechanical scanning. Although this approach is known to be a potentially valuable means of imaging objects with similar acoustical impedances, problems arise when quantitative images of more highly contrasted media such as bones are required. Various strategies and various mathematical procedures for modeling the wave propagation based on Born approximations have been developed at our laboratory, which are suitable for use with pediatric cases. Inversions of the experimental data obtained are presented.

  11. Tomographic method and apparatus

    International Nuclear Information System (INIS)

    Moore, R.M.

    1981-01-01

    A tomographic x-ray machine has a camera and film-plane section which move about a primary axis for imaging a selected cross-section of an anatomical member onto the film. A ''scout image'' of the member is taken at right angles to the plane of the desired cross-section to indicate the cross-section's angle with respect to the primary axis. The film plane is then located at the same angle with respect to a film cassette axis as the selected cross-section makes with the primary axis. The film plane and the cross-section are then maintained in parallel planes throughout motion of the camera and film plane during tomographic radiography. (author)

  12. Tomographic capabilities of the new GEM based SXR diagnostic of WEST

    Science.gov (United States)

    Jardin, A.; Mazon, D.; O'Mullane, M.; Mlynar, J.; Loffelmann, V.; Imrisek, M.; Chernyshova, M.; Czarski, T.; Kasprowicz, G.; Wojenski, A.; Bourdelle, C.; Malard, P.

    2016-07-01

    The tokamak WEST (Tungsten Environment in Steady-State Tokamak) will start operating by the end of 2016 as a test bed for the ITER divertor components in long pulse operation. In this context, radiative cooling of heavy impurities like tungsten (W) in the Soft X-ray (SXR) range [0.1 keV; 20 keV] is a critical issue for the plasma core performances. Thus reliable tools are required to monitor the local impurity density and avoid W accumulation. The WEST SXR diagnostic will be equipped with two new GEM (Gas Electron Multiplier) based poloidal cameras allowing to perform 2D tomographic reconstructions in tunable energy bands. In this paper tomographic capabilities of the Minimum Fisher Information (MFI) algorithm developed for Tore Supra and upgraded for WEST are investigated, in particular through a set of emissivity phantoms and the standard WEST scenario including reconstruction errors, influence of noise as well as computational time.

  13. Tomographic extreme-ultraviolet spectrographs: TESS.

    Science.gov (United States)

    Cotton, D M; Stephan, A; Cook, T; Vickers, J; Taylor, V; Chakrabarti, S

    2000-08-01

    We describe the system of Tomographic Extreme Ultraviolet (EUV) SpectrographS (TESS) that are the primary instruments for the Tomographic Experiment using Radiative Recombinative Ionospheric EUV and Radio Sources (TERRIERS) satellite. The spectrographs were designed to make high-sensitivity {80 counts/s)/Rayleigh [one Rayleigh is equivalent to 10(6) photons/(4pi str cm(2)s)}, line-of-sight measurements of the oi 135.6- and 91.1-nm emissions suitable for tomographic inversion. The system consists of five spectrographs, four identical nightglow instruments (for redundancy and added sensitivity), and one instrument with a smaller aperture to reduce sensitivity and increase spectral resolution for daytime operation. Each instrument has a bandpass of 80-140 nm with approximately 2- and 1-nm resolution for the night and day instruments, respectively. They utilize microchannel-plate-based two-dimensional imaging detectors with wedge-and-strip anode readouts. The instruments were designed, fabricated, and calibrated at Boston University, and the TERRIERS satellite was launched on 18 May 1999 from Vandenberg Air Force Base, California.

  14. Single-photon tomographic determination of regional cerebral blood flow in epilepsy

    International Nuclear Information System (INIS)

    Bonte, F.J.; Devous, M.D. Sr.; Stokely, E.M.; Homan, R.W.

    1983-01-01

    Using a single-photon emission computed tomographic scanner (SPECT) the authors determined regional cerebral blood flow (rCBF) with inhaled xenon-133, a noninvasive procedure. Studies were performed in 40 normal individuals, and these were compared with rCBF determinations in 51 patients with seizure disorders. Although positive results were obtained in 15 of 16 patients with mass lesions, the group of principal interest comprised 25 patients suffering from ''temporal lobe'' epilepsy. Only one of these had a positive x-ray computed tomogram, but 16 had positive findings on rCBF study. These findings included increased local blood flow in the ictal state and reduced flow interictally

  15. A study on measurement of scattery ray of computed tomography

    International Nuclear Information System (INIS)

    Cho, Pyong Kon; Lee, Joon Hyup; Kim, Yoon Sik; Lee, Chang Yeop

    2003-01-01

    Computed tomographic equipment is essential for diagnosis by means of radiation. With passage of time and development of science computed tomographic was developed time and again and in future examination by means of this equipment is expected to increase. In this connection these authors measured rate of scatter ray generation at front of lead glass for patients within control room of computed tomographic equipment room and outside of entrance door for exit and entrance of patients and attempted to find out method for minimizing exposure to scatter ray. From November 2001 twenty five units of computed tomographic equipment which were already installed and operation by 13 general hospitals and university hospitals in Seoul were subjected to this study. As condition of photographing those recommended by manufacturer for measuring exposure to scatter ray was use. At the time objects used DALI CT Radiation Dose Test Phantom fot Head (φ 16 cm Plexglas) and Phantom for Stomache (φ 32 cm Plexglas) were used. For measurement of scatter ray Reader (Radiation Monitor Controller Model 2026) and G-M Survey were used to Survey Meter of Radical Corporation, model 20 x 5-1800, Electrometer/Ion Chamber, S/N 21740. Spots for measurement of scatter ray included front of lead glass for patients within control room of computed tomographic equipment room which is place where most of work by gradiographic personnel are carried out and is outside of entrance door for exit and entrance of patients and their guardians and at spot 100 cm off from isocenter at the time of scanning the object. Work environment within computed tomography room which was installed and under operation by each hospital showed considerable difference depending on circumstances of pertinent hospitals and status of scatter ray was as follows. 1) From isocenter of computed tomographic equipment to lead glass for patients within control room average distance was 377 cm. At that time scatter ray showed diverse

  16. Precision of quantum tomographic detection of radiation

    Energy Technology Data Exchange (ETDEWEB)

    D' Ariano, G.M. (Dipartimento di Fisica ' ' Alessandro Volta' ' , Via A. Bassi 6, I-27100, Pavia (Italy) Istituto Nazionale di Fisica Nucleare, Sezione di Pavia, Via A. Bassi 6, I-27100, Pavia (Italy)); Macchiavello, Chiara (Dipartimento di Fisica ' ' Alessandro Volta' ' , Via A. Bassi 6, I-27100, Pavia (Italy)); Paris, M.G.A. (Dipartimento di Fisica ' ' Alessandro Volta' ' , Via A. Bassi 6, I-27100, Pavia (Italy))

    1994-11-21

    Homodyne tomography provides an experimental technique for reconstructing the density matrix of the radiation field. Here we analyze the tomographic precision in recovering observables like the photon number, the quadrature, and the phase. We show that tomographic reconstruction, despite providing a complete characterization of the state of the field, is generally much less efficient than conventional detection techniques. ((orig.))

  17. Precision of quantum tomographic detection of radiation

    International Nuclear Information System (INIS)

    D'Ariano, G.M.; Macchiavello, Chiara; Paris, M.G.A.

    1994-01-01

    Homodyne tomography provides an experimental technique for reconstructing the density matrix of the radiation field. Here we analyze the tomographic precision in recovering observables like the photon number, the quadrature, and the phase. We show that tomographic reconstruction, despite providing a complete characterization of the state of the field, is generally much less efficient than conventional detection techniques. ((orig.))

  18. Computed tomographic analysis of deformity and dimensional changes in the eyeball

    International Nuclear Information System (INIS)

    Osborne, D.R.; Foulks, G.N.

    1984-01-01

    Computed tomography (CT) was performed in 40 patients with a confirmed ophthalmic diagnosis and a change in the dimensions or configuration of the eyeball. Abnormalities studied included coloboma, microphthalmus, buphthalmos, axial myopia, macrophthalmus, phthisis bulbi, trauma, neoplasm, posterior staphyloma, granuloma, pseudotumor, and surgicalscleral banding for retinal detachment. CT findings could be grouped into three categories depending upon whether the eye was small, large, or normal in size, with the findings in each group allowing distinction of most disease processes

  19. Longitudinal and transverse digital image reconstruction with a tomographic scanner

    International Nuclear Information System (INIS)

    Pickens, D.R.; Price, R.R.; Erickson, J.J.; Patton, J.A.; Partain, C.L.; Rollo, F.D.

    1981-01-01

    A Siemens Gammasonics PHO/CON-192 Multiplane Imager is interfaced to a digital computer for the purpose of performing tomographic reconstructions from the data collected during a single scan. Data from the two moving gamma cameras as well as camera position information are sent to the computer by an interface designed in the authors' laboratory. Backprojection reconstruction is implemented by the computer. Longitudinal images in whole-body format as well as smaller formats are reconstructed for up to six planes simultaneously from the list mode data. Transverse reconstructions are demonstrated for 201 T1 myocardial scans. Post-reconstruction deconvolution processing to remove the blur artifact (characteristic of focal plane tomography) is applied to a multiplane phantom. Digital data acquisition of data and reconstruction of images are practical, and can extend the usefulness of the machine when compared with the film output (author)

  20. An original emission tomograph for in vivo brain imaging of small animals

    International Nuclear Information System (INIS)

    Ochoa, A.V.; Ploux, L.; Mastrippolito, R.

    1996-01-01

    The principle of a new tomograph TOHR dedicated for small volume analysis with very high resolution is presented in this paper. We use uncorrelated multi-photons (X or gamma rays) radioisotopes and a large solid angle focusing collimator to make tomographic imaging without reconstruction algorithm. With this original device, detection efficiency and resolution are independent and submillimetric resolution can be achieved. A feasibility study shows that, made achieve the predicted performances of TOHR. We discuss its potential in rat brain tomography by simulating a realistic neuropharmacological experiment using a 1.4 mm resolution prototype of TOHR under development

  1. Development of a 30-week-pregnant female tomographic model from computed tomography (CT) images for Monte Carlo organ dose calculations

    International Nuclear Information System (INIS)

    Shi Chengyu; Xu, X. George

    2004-01-01

    Assessment of radiation dose and risk to a pregnant woman and her fetus is an important task in radiation protection. Although tomographic models for male and female patients of different ages have been developed using medical images, such models for pregnant women had not been developed to date. This paper reports the construction of a partial-body model of a pregnant woman from a set of computed tomography (CT) images. The patient was 30 weeks into pregnancy, and the CT scan covered the portion of the body from above liver to below pubic symphysis in 70 slices. The thickness for each slice is 7 mm, and the image resolution is 512x512 pixels in a 48 cmx48 cm field; thus, the voxel size is 6.15 mm 3 . The images were segmented to identify 34 major internal organs and tissues considered sensitive to radiation. Even though the masses are noticeably different from other models, the three-dimensional visualization verified the segmentation and its suitability for Monte Carlo calculations. The model has been implemented into a Monte Carlo code, EGS4-VLSI (very large segmented images), for the calculations of radiation dose to a pregnant woman. The specific absorbed fraction (SAF) results for internal photons were compared with those from a stylized model. Small and large differences were found, and the differences can be explained by mass differences and by the relative geometry differences between the source and the target organs. The research provides the radiation dosimetry community with the first voxelized tomographic model of a pregnant woman, opening the door to future dosimetry studies

  2. Investigating Gravity Waves in Polar Mesospheric Clouds Using Tomographic Reconstructions of AIM Satellite Imagery

    Science.gov (United States)

    Hart, V. P.; Taylor, M. J.; Doyle, T. E.; Zhao, Y.; Pautet, P.-D.; Carruth, B. L.; Rusch, D. W.; Russell, J. M.

    2018-01-01

    This research presents the first application of tomographic techniques for investigating gravity wave structures in polar mesospheric clouds (PMCs) imaged by the Cloud Imaging and Particle Size instrument on the NASA AIM satellite. Albedo data comprising consecutive PMC scenes were used to tomographically reconstruct a 3-D layer using the Partially Constrained Algebraic Reconstruction Technique algorithm and a previously developed "fanning" technique. For this pilot study, a large region (760 × 148 km) of the PMC layer (altitude 83 km) was sampled with a 2 km horizontal resolution, and an intensity weighted centroid technique was developed to create novel 2-D surface maps, characterizing the individual gravity waves as well as their altitude variability. Spectral analysis of seven selected wave events observed during the Northern Hemisphere 2007 PMC season exhibited dominant horizontal wavelengths of 60-90 km, consistent with previous studies. These tomographic analyses have enabled a broad range of new investigations. For example, a clear spatial anticorrelation was observed between the PMC albedo and wave-induced altitude changes, with higher-albedo structures aligning well with wave troughs, while low-intensity regions aligned with wave crests. This result appears to be consistent with current theories of PMC development in the mesopause region. This new tomographic imaging technique also provides valuable wave amplitude information enabling further mesospheric gravity wave investigations, including quantitative analysis of their hemispheric and interannual characteristics and variations.

  3. Tomographic scanning apparatus

    International Nuclear Information System (INIS)

    1981-01-01

    Details are given of a tomographic scanning apparatus, with particular reference to the means of adjusting the apparent gain of the signal processing means for receiving output signals from the detectors, to compensate for drift in the gain characteristics, including means for passing a reference signal. (U.K.)

  4. Computed tomographic study on Mycoplasma pneumoniae pneumonia

    International Nuclear Information System (INIS)

    Tanaka, Hiroshi; Koba, Hiroyuki; Mori, Takuji; Mori, Masaki; Tsunematsu, Kazunori; Natori, Hiroshi; Asakawa, Mitsuo; Suzuki, Akira; Doi, Mikio.

    1985-01-01

    Serologically proven 21 patients with Mycoplasma pneumoniae pneumonia that showed infiltrative shadows on chest radiograms were studied by computed tomography (CT). Localization of the lesion and the fashion of its progression through the lung were analyzed. Following 3 loci were defined on the basis of the investigations of critical analysis of the chest radiograms, and of radiopathological analysis of the experimental animal model of mycoplasmal pneumonia with soft X-ray image. I: Peribronchial and periarterial interstitium. II: Bronchiole and its surroundings. III: Lung parenchyma, on hilar area as IIIh, on marginal area as IIIm. Even in the early phase of this disease, radiopathological findings on CT have been distributed in all loci mentioned above. The Shadow disappeared from locus III approximately 14th day from the onset. The shadow have remained, however, loci I, II for a long period. Those findings suggest that locus I and II are one of the major focus of Mycoplasma neumoniae pneumonia. Volume loss in the locus III was observed 78 % of the cases at 28th day from the onset. The shadow on locus IIIh was more prominent than locus IIIm. Reported analytical method with CT could be widely applied to disclose a radiopathological details in other infectious diseases of the lung. (author)

  5. Computed Tomographic Virtual Colonoscopy to Screen for Colorectal Neoplasia in asymptomatic adults

    International Nuclear Information System (INIS)

    Pickhardt, Perry J.; Choi, J Richard; Hwang, Inku and others

    2004-01-01

    We evaluated the performance characteristics of computed tomographic (CT) virtual colonospy for the detection of colorectal neoplasia in an average-risk screening population. A total of 1233 symptomatic adults (mean age, 57.8 years) underwent same-day virtual and optical colonoscopy. Radiologists used the three-dimensional endoluminal display for the initial detection of polyps on CT virtual colonoscopy. For the initial examination of each colonic segment, the colonoscopists were unaware of the findings on virtual colonoscopy, which were revealed to them before any subsequent reexamination. The sensitivity and specificity of virtual colonoscopy and the sensitivity of optical colonoscopy were calculated with the use of the findings of the final, unblinded optical colonoscopy as the reference standard. The sensitivity of virtual colonoscopy for adenomatous polyps was 93.8 percent for polyps at least 10 mm in diameter, 93.9 percent for polyps at least 8 mm in diameter, and 88.7 percent for polyps at least 6 mm in diameter. The sensitivity of optical colonoscopy for adenomatous polyps was 87.5 percent, 91.5 percent, and 92.3 percent for the three sizes of polyps, respectively. The specificity of virtual colonoscopy for adenomatous polyps was 96.0 percent for polyps at least 10 mm in diameter, 92.2 percent for polyps at least 8 mm in diameter, and 79.6 percent for polyps at least 6 mm in diameter.Two polyps were malignant; both were detected on virtual colonoscopy, and one of them was missed on optical colonoscopy before the results on virtual colonoscopy were revealed. CT virtual colonoscopy with the use of a three-dimensional approach is an accurate screening method for the detection of colorectal neoplasia in symptomatic average-risk adults and compares favorably with optical colonoscopy in terms of the detection of clinically relevant lesions

  6. Availability, Indications, and Technical Performance of Computed Tomographic Colonography: A National Survey

    International Nuclear Information System (INIS)

    Fisichella, V.; Hellstroem, M.

    2006-01-01

    Purpose: To determine the availability, indications, and technique of computed tomographic colonography (CTC) in Sweden and to investigate opinions on its future role in colon imaging. Material and Methods: In May 2004, a questionnaire on CTC was mailed to all Departments of Radiology in Sweden, and one year later a telephone interview was conducted with the departments that intended to start a CTC service. Results: Ninety-nine departments (83%) answered the questionnaire, indicating that 23/99 (23.2%) offered a CTC service. Reasons for non-implementation of CTC were lack of CTC training in 34/73 (46.6%) and non-availability of multi-detector row CT scanners in 33/73 (45.2%), while 26% were awaiting further scientific documentation on CTC. Incomplete colonoscopy was the main indication for CTC in 21/23 (91.3%) departments performing CTC. Dual positioning, room air insufflation, and thin-slice collimation were used in all the responding departments. The number of CTC studies performed varied from 1-5 (26.1%) to more than 200 (17.4%). Intravenous contrast material was routinely administered by 9/23 (39.1%) departments. Out of 30 (39.5%) departments that in 2004 intended to start CTC, 9 (30%) had done so by June 2005. A total of 32/99 (32.3%) departments had therefore started CTC by June 2005. Half of the departments that replied believed that CTC would absolutely or probably replace barium enema in the future. Conclusion: The survey shows relatively limited diffusion of CTC practice in Sweden, with approximately one-third of radiology departments offering a CTC service, mostly on a small scale. A wider dissemination of CTC requires further scientific documentation of its capability, intensified educational efforts, and additional funding

  7. Thoracic pathologies on scout views and bolus tracking slices for computed tomographic cerebral angiography

    Energy Technology Data Exchange (ETDEWEB)

    Groth, M.; Fiehler, J.; Buhk, J.H. [University Medical Center Hamburg-Eppendorf (Germany). Dept. of Diagnostic and Interventional Neuroradiology; Henes, F.O. [University Medical Center Hamburg-Eppendorf (Germany). Dept. of Diagnostic and Interventional Radiology

    2015-08-15

    To evaluate the incidence of additional thoracic pathologic findings (TPF) detected on scout views and corresponding bolus tracking slices (SVBT) for computed tomographic cerebral angiography (CTCA) and to test the reliability and accuracy of these findings. The study collective included 505 consecutive patients who underwent multidetector CTCA. Appendant SVBT of all patients were reviewed for any pathologic findings and patient medical reports were analyzed, if any medical treatment was initiated for the detected pathologic findings. In 18 patients thoracic CT scans were performed in the same session. These were additionally reviewed by two blinded observers to test for intra- and interobserver reliability as well as for accuracy of detecting thoracic pathologies on SVBT. TPF were detected in 165 (33 %) SVBT. The five most common pathologic findings were: pleural effusion, 12 %; pneumonia, 8 %; atelectasis/dystelecatsis, 6 %; pericardial effusion, 2 % and elevated diaphragm, 1 %. For 48 % of these findings medical treatment was initiated. SVBT showed a sensitivity of 53 %, a specificity of 99 %, a positive predictive value of 89 %, a negative predictive value of 94 % and accuracy of 94 % for the detection of TPF. The intraobserver reliability was very good and the interobserver reliability showed moderate agreement. SVBT for CTCA should be reviewed with care by radiologists, since additional TPF can affect patient management. Nevertheless, despite a high specificity of SVBT for detecting TPF, an only moderate sensitivity has to be taken into account.

  8. Tomographic array

    International Nuclear Information System (INIS)

    1976-01-01

    A tomographic array with the following characteristics is described. An X-ray screen serving as detector is placed before a photomultiplier tube which itself is placed in front of a television camera connected to a set of image processors. The detector is concave towards the source and is replacable. Different images of the object are obtained simultaneously. Optical fibers and lenses are used for transmission within the system

  9. A positron emission tomograph designed for 3/4 mm resolution

    International Nuclear Information System (INIS)

    McInytre, J.A.; Allen, R.D.; Aguiar, J.; Paulson, J.T.

    1995-01-01

    Two factors of the design for a positron tomograph affect the magnitude of the tomograph spatial resolution: the gamma ray detector width and the analogue measurement of the scintillator location. In the tomograph design reported here the analogue measurement is eliminated and the detector transaxial width factor is reduced to 3/4 mm. The analogue measurement is eliminated by transmitting the scintillation light from each individual scintillator through optical fibers to four photo-multipliers (PMT's); the identities of the PMT's then provide a digital address for the scintillation location. Plastic scintillators are used to provide enough scintillation light for transmission through the optical fibers. Bonuses from the use of plastic scintillators are first, the reduction of the scintillator dead time to about 10 nsec, second, a large reduction of cross-talk between neighboring scintillators, third, the reduction of resolution loss from off-axis gamma rays and, fourth, the ability to sample the axial image at one-eighth the axial resolution distance of 2.5 mm. The designed tomograph incorporates 20 rings. Two of the 32 tomograph 20-ring modules have been constructed to measure the resolution and other characteristics of the tomographs

  10. Introduction to curved rotary tomographic apparatus 'TOMOREX'

    International Nuclear Information System (INIS)

    Kubota, Kazuo; Shinojima, Masayasu; Kohirasawa, Hideo; Tokui, Mitsuru

    1980-01-01

    In recent years, panorama X-ray photographic method is widely used for the X-ray diagnosis of teeth, jawbones and faces. One type based on the principle of tomography is curved surface rotary tomographic method utilizing fine-gap X-ray beam. With the synchronous rotation of an X-ray tube and a photographic film around a face, describing a U-shaped tomographic plane along a dental arch, an upper or lower jawbone is photographed. In the ''TOMOREX'' belonging to this type, is different tomographic planes are available, so that by selecting any position in advance, the part can be photographed. Furthermore, patients can be subjected to examination as laid on a stretcher. The mechanism and equipment, and the photographic method for eye sockets, cheekbones, upper jaw cavities and stereoscopic images are described. (J.P.N.)

  11. Tomographic thallium-201 myocardial perfusion scintigrams after maximal coronary artery vasodilation with intravenous dipyridamole: comparison of qualitative and quantitative approaches

    International Nuclear Information System (INIS)

    Francisco, D.A.; Collins, S.M.; Go, R.T.; Ehrhardt, J.C.; Van Kirk, O.C.; Marcus, M.L.

    1982-01-01

    Eighty-six patients had thallium-201 ( 201 Tl) myocardial perfusion scintigrams after intense coronary artery dilation with i.v. dipyridamole. Tomographic and planar 201 Tl scintigrams were obtained in each patient. Tomographic scintigrams were interpreted using quantitative or visual criteria; planar scintigrams were assessed using visual criteria only. When visual criteria were used, interobserver variability was 40% for tomographic scintigrams and 44% for planar scintigrams. In the 24 patients with normal or nonsignificant CAD, quantitative analysis of the tomograms (range approach) indicated that one of 24 (4%) had a positive image (specificity 96%%); in contrast, when visual criteria were used to interpret the tomographic or planar 201 Tl scintigrams, eight of 24 (33%) had positive scintigrams (specificity 67%). In the 51 abnormal patients, the sensitivity of detecting CAD was 46 of 51 (90%) for tomographic scintigrams interpreted quantitatively, 39 of 51 (76%) for tomographic scintigrams interpreted visually and 41 of 51 (80%) for planar scintigrams assessed visually. The tomographic imaging procedure (quantitative interpretation) also demonstrated a high sensitivity (89%) and specificity (100%) in 28 patients (10 normal and 18 CAD), with a clinical diagnosis of unstable angina pectoris. Overall, the predictive accuracy of an abnormal scintigram with quantitative tomographic imaging (98%) was significantly better (p<0.05) than either qualitative planar or pinhole imaging

  12. Noninvasive detection of coronary artery bypass graft patency by intravenous electron beam computed tomographic angiography.

    Science.gov (United States)

    Yamakami, Shoji; Toyama, Junji; Okamoto, Mitsuhiro; Matsushita, Toyoaki; Murakami, Yoshimasa; Ogata, Masaki; Ito, Shigenori; Fukutomi, Tatsuya; Okayama, Naotsuka; Itoh, Makoto

    2003-11-01

    This study evaluates the usefullness of intravenous electron beam computed tomographic angiography (EBA) for the detection of coronary artery bypass graft patency in 43 patients (33 men and 10 women, mean age, 65 years) who had coronary artery bypass graft surgery. EBA was performed a few days before selective bypass graft angiography (SGA). Forty axial cross-sections of angiographic images of the heart were acquired consecutively by an electrocardiographic trigger signal at 40% of the RR interval, which corresponds to the end-systolic phase. EBA data were reconstructed as a three-dimensional shaded surface display of the heart and bypass grafts. Detectability of the patency of bypass gratis was evaluated, taking selective angiographic images of the bypass grafts as a gold standard. One hundred and nine grafts (96%) out of 114 grafts were subjected to evaluation: 37 grafts were left internal mammary artery grafts (LIMA), 7 were right internal mammary artery grafts (RIMA), 6 were gastroepiploic artery grafts (GEA), 7 were free gastroepiploic artery grafts with venous drainage (free-GEA), 7 were radial artery grafts (RAG), and 45 were saphenous vein gratis (SVG). The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of EBA were 98%, 100%, 100%, 91%, and 98%, respectively. EBA sampled at the end-systolic period was determined to be useful for the detection of coronary artery bypass graft patency and occlusion.

  13. A preoperative mathematic model for computed tomographic guided microwave ablation treatment of hepatic dome tumors.

    Science.gov (United States)

    Gao, Fei; Wang, Guo-Bao; Xiang, Zhan-Wang; Yang, Bin; Xue, Jing-Bing; Mo, Zhi-Qiang; Zhong, Zhi-Hui; Zhang, Tao; Zhang, Fu-Jun; Fan, Wei-Jun

    2016-05-03

    This study sought to prospectively evaluate the feasibility and safety of a preoperative mathematic model for computed tomographic(CT) guided microwave(MW) ablation treatment of hepatic dome tumors. This mathematic model was a regular cylinder quantifying appropriate puncture routes from the bottom up. A total of 103 patients with hepatic dome tumors were enrolled and randomly divided into 2 groups based on whether this model was used or not: Group A (using the model; n = 43) versus Group B (not using the model; n = 60). All tumors were treated by CT-guided MW ablation and follow-up contrast CT were reviewed. The average number of times for successful puncture, average ablation time, and incidence of right shoulder pain were less in Group A than Group B (1.4 vs. 2.5, P = 0.001; 8.8 vs. 11.1 minutes, P = 0.003; and 4.7% vs. 20%, P = 0.039). The technical success rate was higher in Group A than Group B (97.7% vs. 85.0%, P = 0.032). There were no significant differences between the two groups in primary and secondary technique efficacy rates (97.7% vs. 88.3%, P = 0.081; 90.0% vs. 72.7%, P = 0.314). No major complications occurred in both groups. The mathematic model of regular cylinder is feasible and safe for CT-guided MW ablation in treating hepatic dome tumors.

  14. HIGH-PERFORMANCE COMPUTING FOR THE STUDY OF EARTH AND ENVIRONMENTAL SCIENCE MATERIALS USING SYNCHROTRON X-RAY COMPUTED MICROTOMOGRAPHY

    International Nuclear Information System (INIS)

    FENG, H.; JONES, K.W.; MCGUIGAN, M.; SMITH, G.J.; SPILETIC, J.

    2001-01-01

    Synchrotron x-ray computed microtomography (CMT) is a non-destructive method for examination of rock, soil, and other types of samples studied in the earth and environmental sciences. The high x-ray intensities of the synchrotron source make possible the acquisition of tomographic volumes at a high rate that requires the application of high-performance computing techniques for data reconstruction to produce the three-dimensional volumes, for their visualization, and for data analysis. These problems are exacerbated by the need to share information between collaborators at widely separated locations over both local and tide-area networks. A summary of the CMT technique and examples of applications are given here together with a discussion of the applications of high-performance computing methods to improve the experimental techniques and analysis of the data

  15. HIGH-PERFORMANCE COMPUTING FOR THE STUDY OF EARTH AND ENVIRONMENTAL SCIENCE MATERIALS USING SYNCHROTRON X-RAY COMPUTED MICROTOMOGRAPHY.

    Energy Technology Data Exchange (ETDEWEB)

    FENG,H.; JONES,K.W.; MCGUIGAN,M.; SMITH,G.J.; SPILETIC,J.

    2001-10-12

    Synchrotron x-ray computed microtomography (CMT) is a non-destructive method for examination of rock, soil, and other types of samples studied in the earth and environmental sciences. The high x-ray intensities of the synchrotron source make possible the acquisition of tomographic volumes at a high rate that requires the application of high-performance computing techniques for data reconstruction to produce the three-dimensional volumes, for their visualization, and for data analysis. These problems are exacerbated by the need to share information between collaborators at widely separated locations over both local and tide-area networks. A summary of the CMT technique and examples of applications are given here together with a discussion of the applications of high-performance computing methods to improve the experimental techniques and analysis of the data.

  16. Unfolding and smoothing applied to the quality enhancement of neutron tomographic images

    International Nuclear Information System (INIS)

    Almeida, Gevaldo L. de; Silvani, Maria I.; Lopes, Ricardo T.

    2008-01-01

    Resolution and contrast are the major parameters defining the quality of a computer-aided tomographic image. These parameters depend upon several features of the image acquisition system, such as detector resolution, geometrical arrangement of the source-object-detector, beam divergence, source strength, detector efficiency and counting time. Roughly, the detector finite resolution is the main source of systematic errors affecting the separation power of the image acquisition system, while the electronic noise and statistical fluctuation are responsible for the data dispersion, which spoils the contrast. An algorithm has been developed in this work aiming at the improvement of the image quality through the minimization of both types of errors. The systematic ones are reduced by a mathematical unfolding of the position spectra - used as projections to reconstruct the 2D-images - using the Line Spread Function - LSF of the neutron tomographic system. The principle behind this technique is that every single channel contains information about all channels of the spectrum, but it is concealed due to the automatic integration carried out by the detector. Therefore, knowing the shape of this curve, it is possible to retrieve the original spectra. These spectra are unfortunately corrupted by the unavoidable statistical fluctuation, and by oscillations arising from the unfolding process, which strongly affects the quality of the final unfolded image. In order to reduce this impact, the spectra have been filtered by a Fourier transform technique or smoothed with a least square fitting procedure. The algorithm has been applied to spectra of some test-bodies generated by an earlier developed tomographic simulator, which reproduces the spectra furnished by a thermal neutron tomographic system employing a position sensitive detector. The obtained results have shown that the unfolded spectra produce final images capable to resolve features otherwise not achievable with the

  17. Bone mineral density and computer tomographic measurements in correlation with failure strength of equine metacarpal bones

    Directory of Open Access Journals (Sweden)

    Péter Tóth

    2014-01-01

    Full Text Available Information regarding bone mineral density and fracture characteristics of the equine metacarpus are lacking. The aim of this study was to characterize the relationship between mechanical properties of the equine metacarpal bone and its biomechanical and morphometric properties. Third metacarpal bones were extracted from horses euthanized unrelated to musculoskeletal conditions. In total, bone specimens from 26 front limbs of 13 horses (7.8 ± 5.8 years old including Lipizzaner (n = 5, Hungarian Warmblood (n = 2, Holsteiner (n = 2, Thoroughbred (n = 1, Hungarian Sporthorse (n = 1, Friesian (n = 1, and Shagya Arabian (n = 1 were collected. The horses included 7 mares, 4 stallions and 2 geldings. Assessment of the bone mineral density of the whole bone across four specific regions of interest was performed using dual-energy X-ray absorptiometry. The bones were scanned using a computer tomographic scanner to measure cross-sectional morphometric properties such as bone mineral density and cross-sectional dimensions including cortical area and cortical width. Mechanical properties (breaking force, bending strength, elastic modulus were determined by a 3-point bending test. Significant positive linear correlations were found between the breaking force and bone mineral density of the entire third metacarpal bones (P P P in vivo investigations.

  18. Tomographic array

    International Nuclear Information System (INIS)

    1976-01-01

    The configuration of a tomographic array in which the object can rotate about its axis is described. The X-ray detector is a cylindrical screen perpendicular to the axis of rotation. The X-ray source has a line-shaped focus coinciding with the axis of rotation. The beam is fan-shaped with one side of this fan lying along the axis of rotation. The detector screen is placed inside an X-ray image multiplier tube

  19. Thanatophoric dysplasia: case report of an autopsy complemented by postmortem computed tomographic study

    Directory of Open Access Journals (Sweden)

    Éber Emanuel Mayoral

    2014-06-01

    Full Text Available Thanatophoric dysplasia (TD is one of the most common lethal skeletal dysplasias, which was first designated as thanatophoric dwarfism and described in 1967. The authors report a case of a Caucasian girl with TD, born to a 31-year-old woman without comorbidities. The newborn presented respiratory distress immediately after delivery, progressing to death in less than 2 hours. An autopsy was carried out after postmortem tomographic examination. The autopsy findings depicted extensive malformations of the skeletal system and the brain. The aim of this report is to discuss the pathogenesis and correlate the morphologic features of TD that were disclosed at the tomography and the autopsy.

  20. Fusion imaging of computed tomographic pulmonary angiography and SPECT ventilation/perfusion scintigraphy: initial experience and potential benefit

    International Nuclear Information System (INIS)

    Harris, Benjamin; Bailey, Dale; Roach, Paul; Bailey, Elizabeth; King, Gregory

    2007-01-01

    The objective of this study was to examine the feasibility of fusing ventilation and perfusion data from single-photon emission computed tomography (SPECT) ventilation perfusion (V/Q) scintigraphy together with computed tomographic pulmonary angiography (CTPA) data. We sought to determine the accuracy of this fusion process. In addition, we correlated the findings of this technique with the final clinical diagnosis. Thirty consecutive patients (17 female, 13 male) who had undergone both CTPA and SPECT V/Q scintigraphy during their admission for investigation of potential pulmonary embolism were identified retrospectively. Image datasets from these two modalities were co-registered and fused using commercial software. Accuracy of the fusion process was determined subjectively by correlation between modalities of the anatomical boundaries and co-existent pleuro-parenchymal abnormalities. In all 30 cases, SPECT V/Q images were accurately fused with CTPA images. An automated registration algorithm was sufficient alone in 23 cases (77%). Additional linear z-axis scaling was applied in seven cases. There was accurate topographical co-localisation of vascular, parenchymal and pleural disease on the fused images. Nine patients who had positive CTPA performed as an initial investigation had co-localised perfusion defects on the subsequent fused CTPA/SPECT images. Three of the 11 V/Q scans initially reported as intermediate could be reinterpreted as low probability owing to co-localisation of defects with parenchymal or pleural pathology. Accurate fusion of SPECT V/Q scintigraphy to CTPA images is possible. This technique may be clinically useful in patients who have non-diagnostic initial investigations or in whom corroborative imaging is sought. (orig.)

  1. Detection of common bile duct stones: comparison between endoscopic ultrasonography, magnetic resonance cholangiography, and helical-computed-tomographic cholangiography

    International Nuclear Information System (INIS)

    Kondo, Shintaro; Isayama, Hiroyuki; Akahane, Masaaki; Toda, Nobuo; Sasahira, Naoki; Nakai, Yosuke; Yamamoto, Natsuyo; Hirano, Kenji; Komatsu, Yutaka; Tada, Minoru; Yoshida, Haruhiko; Kawabe, Takao; Ohtomo, Kuni; Omata, Masao

    2005-01-01

    Objectives: New modalities, namely, endoscopic ultrasonography (EUS), magnetic resonance cholangiopancreatography (MRCP), and helical computed-tomographic cholangiography (HCT-C), have been introduced recently for the detection of common bile duct (CBD) stones and shown improved detectability compared to conventional ultrasound or computed tomography. We conducted this study to compare the diagnostic ability of EUS, MRCP, and HCT-C in patients with suspected choledocholithiasis. Methods: Twenty-eight patients clinically suspected of having CBD stones were enrolled, excluding those with cholangitis or a definite history of choledocholithiasis. Each patient underwent EUS, MRCP, and HCT-C prior to endoscopic retrograde cholangio-pancreatography (ERCP), the result of which served as the diagnostic gold standard. Results: CBD stones were detected in 24 (86%) of 28 patients by ERCP/IDUS. The sensitivity of EUS, MRCP, and HCT-C was 100%, 88%, and 88%, respectively. False negative cases for MRCP and HCT-C had a CBD stone smaller than 5 mm in diameter. No serious complications occurred while one patient complained of itching in the eyelids after the infusion of contrast agent on HCT-C. Conclusions: When examination can be scheduled, MRCP or HCT-C will be the first choice because they were less invasive than EUS. MRCP and HCT-C had similar detectability but the former may be preferable considering the possibility of allergic reaction in the latter. When MRCP is negative, EUS is recommended to check for small CBD stones

  2. Terahertz wave tomographic imaging with a Fresnel lens

    Institute of Scientific and Technical Information of China (English)

    S. Wang; X.-C. Zhang

    2003-01-01

    We demonstrate three-dimensional tomographic imaging using a Fresnel lens with broadband terahertz pulses. Objects at various locations along the beam propagation path are uniquely imaged on the same imaging plane using a Fresnel lens with different frequencies of the imaging beam. This procedure allows the reconstruction of an object's tomographic contrast image by assembling the frequency-dependent images.

  3. Dose determination in computed tomography

    International Nuclear Information System (INIS)

    Descamps, C.; Garrigo, E.; Venencia, D.; Gonzalez, M.; Germanier, A.

    2011-10-01

    In the last years the methodologies to determine the dose in computed tomography have been revised. In this work was realized a dosimetric study about the exploration protocols used for simulation of radiotherapy treatments. The methodology described in the Report No. 111 of the American Association of Medical Physiques on a computed tomograph of two cuts was applied. A cylindrical phantom of water was used with dimensions: 30 cm of diameter and 50 cm of longitude that simulates the absorption and dispersion conditions of a mature body of size average. The doses were determined with ionization chamber and thermoluminescent dosimetry. The results indicate that the dose information that provides the tomograph underestimates the dose between 32 and 35%.

  4. Industrial dynamic tomographic reconstruction

    International Nuclear Information System (INIS)

    Oliveira, Eric Ferreira de

    2016-01-01

    The state of the art methods applied to industrial processes is currently based on the principles of classical tomographic reconstructions developed for tomographic patterns of static distributions, or is limited to cases of low variability of the density distribution function of the tomographed object. Noise and motion artifacts are the main problems caused by a mismatch in the data from views acquired in different instants. All of these add to the known fact that using a limited amount of data can result in the presence of noise, artifacts and some inconsistencies with the distribution under study. One of the objectives of the present work is to discuss the difficulties that arise from implementing reconstruction algorithms in dynamic tomography that were originally developed for static distributions. Another objective is to propose solutions that aim at reducing a temporal type of information loss caused by employing regular acquisition systems to dynamic processes. With respect to dynamic image reconstruction it was conducted a comparison between different static reconstruction methods, like MART and FBP, when used for dynamic scenarios. This comparison was based on a MCNPx simulation as well as an analytical setup of an aluminum cylinder that moves along the section of a riser during the process of acquisition, and also based on cross section images from CFD techniques. As for the adaptation of current tomographic acquisition systems for dynamic processes, this work established a sequence of tomographic views in a just-in-time fashion for visualization purposes, a form of visually disposing density information as soon as it becomes amenable to image reconstruction. A third contribution was to take advantage of the triple color channel necessary to display colored images in most displays, so that, by appropriately scaling the acquired values of each view in the linear system of the reconstruction, it was possible to imprint a temporal trace into the regularly

  5. Comparison among tomographic reconstruction with limited data

    International Nuclear Information System (INIS)

    Oliveira, Eric F.; Dantas, Carlos C.; Vasconcelos, Daniel A.A.; Cadiz, Luis F.; Melo, Silvio B.

    2011-01-01

    Nowadays there is a continuing interest in applying computed tomography (CT) techniques in non-destructive testing and inspection of many industrial products. These applications of CT usually require a differentiated analysis when there are strong limitations in acquiring a sufficiently large amount of projection data. The use of a low number of tomographic data normally degrades the quality of the reconstructed image, highlighting the formation of artifacts and noise. This work investigates the reconstruction methods most commonly used (FBP, ART, SIRT, MART, SMART) and shows the performance of each one in this limited scenario. For this purpose, all methods were implemented and tested with a phantom of uniform density with well-known distribution, with measures of transmission of gamma radiation in a first generation CT scanner. The phantom is a concentric stainless steel tube coupled with a half - cylinder of aluminum. The measurements were made with an highest root mean square error, with the formation of visible artifacts. The artifacts are diminished but still visible in the ART and SIRT techniques, and the best performance was observed with the techniques MART and SMART. The technical superiority of these multiplicative methods is clearly seen in the reconstructed image quality, endorsing their application to situations of limited input data. (author)

  6. Relation of the measuring values in cephalometric radiographs and TMJ tomographs

    Energy Technology Data Exchange (ETDEWEB)

    Han, Jin Woo [Kangnung National Univ. College of Dentistry, Kangnung (Korea, Republic of)

    2007-03-15

    To examine whether the maxillofacial skeletal morphology correlates with the condylar position and the anatomic characteristics of articular eminence using measurements of lateral cephalometric radiographs and individualized sagittal temporomandibular joint (TMJ) tomographs. I compared measurements of 202 TMJs of 101 orthodontic patients of Kangnung National University Dental Hospital. I used Pearson's correlation for comparison of the measuring values in lateral cephalometric radiographs and individualized sagittal TMJ tomographs. Large occlusal plane angle tendency showed decreased width of posterior eminence slope, decreased depth of articular fossa and decreased posterior slope angle of eminence. Large mandibular plane angle tendency showed decreased superior joint space, decreased superior joint space, decreased depth of articular fossa and decreased posterior slope angle of eminence. Large genial angle tendency showed decreased depth of articular fossa, decreased posterior slope angle of eminence and anterior position of comdylar head. Large anterior facial height and large posterior facial height tendency showed increased width of posterior position of condylar head. Maxillofacial skeletal morphology has correlation with the anatomic characteristics of TMJ. Individualized sagittal TMJ tomographs can provide useful information for anatomical analysis of TMJ.

  7. Visual and semiquantitative analysis of 18F-fluorodeoxyglucose positron emission tomography using a partial-ring tomograph without attenuation correction to differentiate benign and malignant pulmonary nodules

    International Nuclear Information System (INIS)

    Skehan, S.J.; Coates, G.; Otero, C.; O'Donovan, N.; Pelling, M.; Nahmias, C.

    2001-01-01

    Many studies have reported the use of attenuation-corrected positron emission tomography with 18 F-fluorodeoxyglucose (FDG PET) with full-ring tomographs to differentiate between benign and malignant pulmonary nodules. We sought to evaluate FDG PET using a partial-ring tomograph without attenuation correction. A retrospective review of PET images from 77 patients (range 38-84 years of age) with proven benign or malignant pulmonary nodules was undertaken. All images were obtained using a Siemens/CTI ECAT ART tomograph, without attenuation correction, after 185 MBq 18 F-FDG was injected. Images were visually graded on a 5-point scale from 'definitely malignant' to 'definitely benign,' and lesion-to-background (LB) ratios were calculated using region of interest analysis. Visual and semiquantitative analyses were compared using receiver operating characteristic analysis. Twenty lesions were benign and 57 were malignant. The mean LB ratio for benign lesions was 1.5 (range 1.0-5.7) and for malignant lesions 5.7 (range 1.2-14.1) (p < 0.001). The area under the ROC curve for LB ratio analysis was 0.95, and for visual analysis 0.91 (p = 0.39). The optimal cut-off ratio with LB ratio analysis was 1.8, giving a sensitivity of 95% and a specificity of 85%. For lesions thought to be 'definitely malignant' on visual analysis, the sensitivity was 93% and the specificity 85%. Three proven infective lesions were rated as malignant by both techniques (LB ratio 2.6-5.7). FDG PET without attenuation correction is accurate for differentiating between benign and malignant lung nodules. Results using simple LB ratios without attenuation correction compare favourably with the published sensitivity and specificity for standard uptake ratios. Visual analysis is equally accurate. (author)

  8. Tomographic Aspects of Advanced Active Pulmonary Tuberculosis and Evaluation of Sequelae following Treatment

    Directory of Open Access Journals (Sweden)

    Rafael Barcelos Capone

    2017-01-01

    Full Text Available Objectives. To evaluate tomographic changes in pulmonary tuberculosis (TB, degree of agreement among three radiologists regarding tomographic diagnoses, and sequelae following treatment. Methods. Cross-sectional and descriptive study of 74 TB patients confirmed by sputum culture and chest computed tomography before (CT1 and 6 months after (CT2 drug therapy. Results were performed by three radiologists blinded to clinical and laboratory results. Results. Main findings in CT1 included nodules indicating the presence of a tree-in-bud pattern in 93% of cases, ill-defined nodules in 84% of cases, consolidation in 77% of cases, architectural distortion in 71% of cases, cavitary lesions in 62% of cases, and ground glass opacities in 37% of cases. Airway involvement, characterized by increased thickness and dilatation of the bronchial walls, occurred in 93% of cases. Pleural involvement occurred in 54%. There was an agreement on active TB among the three radiologists in 85% of cases. The results in CT2 indicated the presence of architectural distortion in 91% of cases and cylindrical bronchiectasis in 86%. Conclusions. The study established a tomographic pattern for diagnosis of active TB characterized by the presence of airway nodules, consolidation, architectural distortion, and cavitary lesions, and an almost complete degree of agreement (Kappa was observed among the radiologists (0.85. CT after treatment assists in defining the cure.

  9. A 3D tomographic EBSD analysis of a CVD diamond thin film

    International Nuclear Information System (INIS)

    Liu Tao; Raabe, Dierk; Zaefferer, Stefan

    2008-01-01

    We have studied the nucleation and growth processes in a chemical vapor deposition (CVD) diamond film using a tomographic electron backscattering diffraction method (3D EBSD). The approach is based on the combination of a focused ion beam (FIB) unit for serial sectioning in conjunction with high-resolution EBSD. Individual diamond grains were investigated in 3-dimensions particularly with regard to the role of twinning.

  10. Improving appropriate use of echocardiography and single-photon emission computed tomographic myocardial perfusion imaging: a continuous quality improvement initiative.

    Science.gov (United States)

    Johnson, Thomas V; Rose, Geoffrey A; Fenner, Deborah J; Rozario, Nigel L

    2014-07-01

    Appropriate use criteria for cardiovascular imaging have been published, but compliance in practice has been incomplete, with persistent high rates of inappropriate use. The aim of this study was to show the efficacy of a continuous quality improvement (CQI) initiative to favorably influence the appropriate use of outpatient transthoracic echocardiography and single-photon emission computed tomographic (SPECT) myocardial perfusion imaging (MPI) in a large cardiovascular practice. In this prospective study, a multiphase CQI initiative was implemented, and its impact on ordering patterns for outpatient transthoracic echocardiography and SPECT MPI was assessed. Between November and December 2010, a baseline analysis of the application of appropriate use criteria to indications for outpatient transthoracic echocardiographic studies (n = 203) and SPECT MPI studies (n = 205) was performed, with studies categorized as "appropriate," "inappropriate," "uncertain," or "unclassified." The CQI initiative was then begun, with (1) clinician education, including didactic lectures and case-based presentations with audience participation; (2) system changes in ordering processes, with redesigned image ordering forms; and (3) peer review and feedback. A follow-up analysis was then performed between June and August 2012, with categorization of indications for transthoracic echocardiographic studies (n = 206) and SPECT MPI studies (n = 206). At baseline, 73.9% of echocardiographic studies were categorized as appropriate, 16.7% as inappropriate, 5.9% as uncertain, and 3.4% as unclassified. Similarly, for SPECT MPI studies 71.7% were categorized as appropriate, 18.5% as inappropriate, 7.8% as uncertain, and 1.9% as unclassified. Separate analysis of the two most important categories, appropriate and inappropriate, demonstrated a significant improvement after the CQI initiative, with a 63% reduction in inappropriate echocardiographic studies (18.5% vs 6.9%, P = .0010) and a 46% reduction

  11. Computed tomographic, magnetic resonance imaging, and cross-sectional anatomic features of the manus in a normal American black bear (Ursus americanus).

    Science.gov (United States)

    Ober, C P; Freeman, L E

    2010-06-01

    The purpose of this study was to provide a detailed description of cross-sectional anatomic structures of the manus of a black bear cadaver and correlate anatomic findings with corresponding features in computed tomographic (CT) and magnetic resonance (MR) images. CT, MR imaging, and transverse sectioning were performed on the thoracic limb of a cadaver female black bear which had no evidence of lameness or thoracic limb abnormality prior to death. Features in CT and MR images corresponding to clinically important anatomic structures in anatomic sections were identified. Most of the structures identified in transverse anatomic sections were also identified using CT and MR imaging. Bones, muscles and tendons were generally easily identified with both imaging modalities, although divisions between adjacent muscles were rarely visible with CT and only visible sometimes with MR imaging. Vascular structures could not be identified with either imaging modality.

  12. Clinical observations of the brain abscesses, especially on the computed tomographic brain scan findings

    International Nuclear Information System (INIS)

    Kitano, Masahiko; Kuroda, Ryotaro; Yamada, Yasufumi; Yorimae, Akira; Akai, Fumiharu; Watanabe, Masaru; Nakatani, Jiro; Ioku, Masahiko

    1988-01-01

    Fifteen cases with pyogenic brain abscess were experienced in our clinic during the last 7 years. The records of these patients were examined to evaluate the clinical stage and the result of several treatments. In 12 operative cases, diagnosis was made by fluid aspirated from the abscess. Bacteria were cultured from the fluid in 5 among these cases. In 3 other non-operative patients, diagnosis was based on computed tomographic (CT) brain scans and laboratory studies. Each volume of the brain abscess and surrounding brain edema was measured on serial CT scans to evaluate the clinical stage and the abscess evolution. In symptoms and signs, it has been thought that one of the factors contributing to mortality was the level of consciousness. In this study, the disturbance of consciousness did not correlate with the size of abscess, but with that of edema. The cases reported here were divided into 3 groups according to the volume of abscess and of edema on initial CT scans. The cases of group A had small surrounding edema ( 50 ml) and small abscess ( 25 ml). The group A had slight change in the clinical status and the size of edema, but the others had severe change. Three phase changes in edema size were seen in the group B regardless of therapeutic modalities ; showing almost constant increase in first 2 weeks, great decrease in second 2 weeks and moderate decrease following these 4 weeks. In the group C, however, these phases were seen only in early operation cases. (J.P.N.)

  13. Arbitrary layer tomographic method and apparatus

    International Nuclear Information System (INIS)

    Kato, H.; Ishida, M.

    1984-01-01

    Many two-dimensional X-ray projection distribution images obtained by exposing an object to X-rays in various directions are once stored in positions different from one another in a stimulable phosphor sheet or respectively in many stimulable phosphor sheets. The stimulable phosphor sheet or sheets are then scanned with stimulating rays, and the light emitted thereby from the stimulable phosphor sheet or sheets is photoelectrically read out to obtain electric signals representing the X-ray projection distribution images. The electric signals are processed to obtain a tomographic image of an arbitrary tomographic layer of the object

  14. Gamma Ray Tomographic Scan Method for Large Scale Industrial Plants

    International Nuclear Information System (INIS)

    Moon, Jin Ho; Jung, Sung Hee; Kim, Jong Bum; Park, Jang Geun

    2011-01-01

    The gamma ray tomography systems have been used to investigate a chemical process for last decade. There have been many cases of gamma ray tomography for laboratory scale work but not many cases for industrial scale work. Non-tomographic equipment with gamma-ray sources is often used in process diagnosis. Gamma radiography, gamma column scanning and the radioisotope tracer technique are examples of gamma ray application in industries. In spite of many outdoor non-gamma ray tomographic equipment, the most of gamma ray tomographic systems still remained as indoor equipment. But, as the gamma tomography has developed, the demand on gamma tomography for real scale plants also increased. To develop the industrial scale system, we introduced the gamma-ray tomographic system with fixed detectors and rotating source. The general system configuration is similar to 4 th generation geometry. But the main effort has been made to actualize the instant installation of the system for real scale industrial plant. This work would be a first attempt to apply the 4th generation industrial gamma tomographic scanning by experimental method. The individual 0.5-inch NaI detector was used for gamma ray detection by configuring circular shape around industrial plant. This tomographic scan method can reduce mechanical complexity and require a much smaller space than a conventional CT. Those properties make it easy to get measurement data for a real scale plant

  15. Tomographic Approach in Three-Orthogonal-Basis Quantum Key Distribution

    International Nuclear Information System (INIS)

    Liang Wen-Ye; Yin Zhen-Qiang; Chen Hua; Li Hong-Wei; Chen Wei; Han Zheng-Fu; Wen Hao

    2015-01-01

    At present, there is an increasing awareness of some three-orthogonal-basis quantum key distribution protocols, such as, the reference-frame-independent (RFI) protocol and the six-state protocol. For secure key rate estimations of these protocols, there are two methods: one is the conventional approach, and another is the tomographic approach. However, a comparison between these two methods has not been given yet. In this work, with the general model of rotation channel, we estimate the key rate using conventional and tomographic methods respectively. Results show that conventional estimation approach in RFI protocol is equivalent to tomographic approach only in the case of that one of three orthogonal bases is always aligned. In other cases, tomographic approach performs much better than the respective conventional approaches of the RFI protocol and the six-state protocol. Furthermore, based on the experimental data, we illustrate the deep connections between tomography and conventional RFI approach representations. (paper)

  16. Computed tomographic diagnosis of pulmonary artery aneurysm

    International Nuclear Information System (INIS)

    Maeno, Kouji; Kontani, Kazuhiro; Ito, Makoto; Sakurai, Noboru; Sawada, Taisei; Fukeda, Yasuhiko; Takata, Shigeo; Ikeda, Takayuki; Hattori, Nobu.

    1986-01-01

    Pulmonary artery aneurysms are rare lesions. Clagett et al reported that one aneurysm of the pulmonary artery may be found in approximately 14,000 necropsies. We have experienced a case of giant pulmonary artery aneurysm confirmed by computed tomography. A 38 year-old man with atrial septal defect admitted to Kanazawa City Hospital. He had been pointed out of a right hilar mass when he was 26 years old. His complaint was bloody sputum and cough. Pulmonary angiography was not useful for the definite diagnosis because of its mural thrombi. Enhanced computed tomography showed a giant pulmonary artery aneurysm with a mural thrombi in its cavity. This shows that enhanced computed tomography is very useful for the diagnosis of a pulmonary artery aneurysm with a mural thrombi in its cavity. (author)

  17. Computed tomographic diagnosis of pulmonary artery aneurysm

    Energy Technology Data Exchange (ETDEWEB)

    Maeno, Kouji; Kontani, Kazuhiro; Ito, Makoto; Sakurai, Noboru; Sawada, Taisei; Fukeda, Yasuhiko; Takata, Shigeo; Ikeda, Takayuki; Hattori, Nobu

    1986-05-01

    Pulmonary artery aneurysms are rare lesions. Clagett et al reported that one aneurysm of the pulmonary artery may be found in approximately 14,000 necropsies. We have experienced a case of giant pulmonary artery aneurysm confirmed by computed tomography. A 38 year-old man with atrial septal defect admitted to Kanazawa City Hospital. He had been pointed out of a right hilar mass when he was 26 years old. His complaint was bloody sputum and cough. Pulmonary angiography was not useful for the definite diagnosis because of its mural thrombi. Enhanced computed tomography showed a giant pulmonary artery aneurysm with a mural thrombi in its cavity. This shows that enhanced computed tomography is very useful for the diagnosis of a pulmonary artery aneurysm with a mural thrombi in its cavity.

  18. Computed tomographic (CT) study of watershed area supplied by the posterior inferior cerebellar artery (PICA)

    International Nuclear Information System (INIS)

    Nozaki, Junichi; Hirose, Satoshi; Hosotani, Kazuo; Kubota, Tetsuya; Kubota, Norihiko.

    1990-01-01

    Thirteen patients with clinical and computed tomographic (CT) evidence of cerebellar infarction were examined during 1987-1989. Six patients had onset of cerebellar infarction at ages ranging from 45 to 69, and seven patients had onset at ages over 70. In thirteen cases, we observed infarction in the inferior region of the cerebellum, and we studied these cases. CT demonstrated decreased density in 4 distinct anatomic areas. These areas are listed below, with estimation of the distribution of the hemispheric arteries of the posterior inferior cerebellar artery (PICA): Group 1 - posterior medial area, probably territory of the inferior vermian branch, tonsillar branch and/or medial artery of the hemispheric artery of the PICA; Group 2 - posterior intermediate area, probably territory of the intermediate artery of the hemispheric artery of the PICA; Group 3 - area including both areas of group 1 and group 3; Group 4 - lateral area, just posterior to pyramis, probably territory of the anterior inferior cerebellar artery and/or lateral artery of the hemispheric artery of PICA. The medial and intermedial cerebellar hemispheric segments were most commonly affected but the lateral segment was not. The PICA least frequently supplied the lateral segments. While the anterior inferior cerebellar artery usually anastomoses with the lateral artery of the hemispheric artery of the PICA. These vascular territories may provide good collateral circulation to this segment. And we also estimate the distribution of the PICA by the CT findings. (author)

  19. A 3D tomographic EBSD analysis of a CVD diamond thin film

    Directory of Open Access Journals (Sweden)

    Tao Liu, Dierk Raabe and Stefan Zaefferer

    2008-01-01

    Full Text Available We have studied the nucleation and growth processes in a chemical vapor deposition (CVD diamond film using a tomographic electron backscattering diffraction method (3D EBSD. The approach is based on the combination of a focused ion beam (FIB unit for serial sectioning in conjunction with high-resolution EBSD. Individual diamond grains were investigated in 3-dimensions particularly with regard to the role of twinning.

  20. Computed tomography in the evaluation of acquired stenosis in the neonate

    International Nuclear Information System (INIS)

    Faw, K.; Muntz, H.; Siegel, M.; Spector, G.

    1982-01-01

    We studied the feasibility of computed tomographic evaluation of the neonatal airway. Three neonatal larynges, removed at necroscopy, were examined by computed tomography. Good resolution of soft tissue, cartilage and airway lumen was obtained in these small specimens. On the basis of these findings two neonates with acquired subglottic stenosis were examined by endoscopy, soft tissue airway radiographs, and computed tomography. Measurements of radiation dose revealed that a computed tomographic study delivered 36% of the mean tissue dose of standard image intensifier fluoroscopy. Computed tomography and fluoroscopy both demonstrated the degree and length of this stenosis accurately. An advantage of CT over conventional imaging procedures was better definition of the cross sectional area of the airway

  1. Anisakiasis presenting to the ED: clinical manifestations, time course, hematologic tests, computed tomographic findings, and treatment.

    Science.gov (United States)

    Takabayashi, Takeshi; Mochizuki, Toshiaki; Otani, Norio; Nishiyama, Kei; Ishimatsu, Shinichi

    2014-12-01

    The prevalence of anisakiasis is rare in the United States and Europe compared with that in Japan, with few reports of its presentation in the emergency department (ED). This study describes the clinical, hematologic, computed tomographic (CT) characteristics, and treatment in gastric and small intestinal anisakiasis patients in the ED. We retrospectively reviewed the data of 83 consecutive anisakiasis presentations in our ED between 2003 and 2012. Gastric anisakiasis was endoscopically diagnosed with the Anisakis polypide. Small intestinal anisakiasis was diagnosed based on both hematologic (Anisakis antibody) and CT findings. Of the 83 cases, 39 had gastric anisakiasis and 44 had small intestinal anisakiasis based on our diagnostic criteria. Although all patients had abdominal pain, the gastric anisakiasis group developed symptoms significantly earlier (peaking within 6 hours) than the small intestinal anisakiasis group (peaking within 48 hours), and fewer patients with gastric anisakiasis needed admission therapy (5% vs 57%, Pfindings revealed edematous wall thickening in all patients, and ascites and phlegmon of the mesenteric fat were more frequently observed in the small intestinal anisakiasis group. In the ED, early and accurate diagnosis of anisakiasis is important to treat and explain to the patient, and diagnosis can be facilitated by a history of raw seafood ingestion, evaluation of the time-to-symptom development, and classic CT findings. Copyright © 2014 Elsevier Inc. All rights reserved.

  2. 256-Slice coronary computed tomographic angiography in patients with atrial fibrillation: optimal reconstruction phase and image quality

    Energy Technology Data Exchange (ETDEWEB)

    Oda, Seitaro; Yuki, Hideaki; Kidoh, Masafumi; Utsunomiya, Daisuke; Nakaura, Takeshi; Namimoto, Tomohiro; Yamashita, Yasuyuki [Kumamoto University, Department of Diagnostic Radiology, Faculty of Life Sciences, Chuou-ku, Kumamoto (Japan); Honda, Keiichi; Yoshimura, Akira; Katahira, Kazuhiro [Kumamoto Chuo Hospital, Department of Diagnostic Radiology, Minami-ku, Kumamoto (Japan); Noda, Katsuo; Oshima, Shuichi [Kumamoto Chuo Hospital, Department of Cardiology, Minami-ku, Kumamoto (Japan)

    2016-01-15

    To assess the optimal reconstruction phase and the image quality of coronary computed tomographic angiography (CCTA) in patients with atrial fibrillation (AF). We performed CCTA in 60 patients with AF and 60 controls with sinus rhythm. The images were reconstructed in multiple phases in all parts of the cardiac cycle, and the optimal reconstruction phase with the fewest motion artefacts was identified. The coronary artery segments were visually evaluated to investigate their assessability. In 46 (76.7 %) patients, the optimal reconstruction phase was end-diastole, whereas in 6 (10.0 %) patients it was end-systole or mid-diastole, and in 2 (3.3 %) patients it was another cardiac phase. In 53 (88.3 %) of the controls, the optimal reconstruction phase was mid-diastole, whereas it was end-systole in 4 (6.7 %), and in 3 (5.0 %) it was another cardiac phase. There was a significant difference between patients with AF and the controls in the optimal phase (p < 0.01) but not in the visual image quality score (p = 0.06). The optimal reconstruction phase in most patients with AF was the end-diastolic phase. The end-systolic phase tended to be optimal in AF patients with higher average heart rates. (orig.)

  3. Is triple contrast computed tomographic scanning useful in the selective management of stab wounds to the back?

    Science.gov (United States)

    McAllister, E; Perez, M; Albrink, M H; Olsen, S M; Rosemurgy, A S

    1994-09-01

    We devised a protocol to prospectively manage stab wounds to the back with the hypothesis that the triple contrast computed tomographic (CT) scan is an effective means of detecting occult injury in these patients. All wounds to the back in hemodynamically stable adults were locally explored. All patients with muscular fascial penetration underwent triple contrast CT scanning utilizing oral, rectal, and IV contrast. Patients did not undergo surgical exploration if their CT scan was interpreted as negative or if the CT scan demonstrated injuries not requiring surgical intervention. Fifty-three patients were entered into the protocol. The time to complete the triple contrast CT scan ranged from 3 to 6 hours at a cost of $1050 for each scan. In 51 patients (96%), the CT scan either had negative findings (n = 31) or showed injuries not requiring exploration (n = 20). These patients did well with nonsurgical management. Two CT scans documented significant injury and led to surgical exploration and therapeutic celiotomies. Although triple contrast CT scanning was able to detect occult injury in patients with stab wounds to the back it did so at considerable cost and the results rarely altered clinical care. Therefore, its routine use in these patients is not recommended.

  4. Multidetector computed tomographic pulmonary angiography in patients with a high clinical probability of pulmonary embolism.

    Science.gov (United States)

    Moores, L; Kline, J; Portillo, A K; Resano, S; Vicente, A; Arrieta, P; Corres, J; Tapson, V; Yusen, R D; Jiménez, D

    2016-01-01

    ESSENTIALS: When high probability of pulmonary embolism (PE), sensitivity of computed tomography (CT) is unclear. We investigated the sensitivity of multidetector CT among 134 patients with a high probability of PE. A normal CT alone may not safely exclude PE in patients with a high clinical pretest probability. In patients with no clear alternative diagnosis after CTPA, further testing should be strongly considered. Whether patients with a negative multidetector computed tomographic pulmonary angiography (CTPA) result and a high clinical pretest probability of pulmonary embolism (PE) should be further investigated is controversial. This was a prospective investigation of the sensitivity of multidetector CTPA among patients with a priori clinical assessment of a high probability of PE according to the Wells criteria. Among patients with a negative CTPA result, the diagnosis of PE required at least one of the following conditions: ventilation/perfusion lung scan showing a high probability of PE in a patient with no history of PE, abnormal findings on venous ultrasonography in a patient without previous deep vein thrombosis at that site, or the occurrence of venous thromboembolism (VTE) in a 3-month follow-up period after anticoagulation was withheld because of a negative multidetector CTPA result. We identified 498 patients with a priori clinical assessment of a high probability of PE and a completed CTPA study. CTPA excluded PE in 134 patients; in these patients, the pooled incidence of VTE was 5.2% (seven of 134 patients; 95% confidence interval [CI] 1.5-9.0). Five patients had VTEs that were confirmed by an additional imaging test despite a negative CTPA result (five of 48 patients; 10.4%; 95% CI 1.8-19.1), and two patients had objectively confirmed VTEs that occurred during clinical follow-up of at least 3 months (two of 86 patients; 2.3%; 95% CI 0-5.5). None of the patients had a fatal PE during follow-up. A normal multidetector CTPA result alone may not safely

  5. Global seismic tomography and modern parallel computers

    Directory of Open Access Journals (Sweden)

    A. Piersanti

    2006-06-01

    Full Text Available A fast technological progress is providing seismic tomographers with computers of rapidly increasing speed and RAM, that are not always properly taken advantage of. Large computers with both shared-memory and distributedmemory architectures have made it possible to approach the tomographic inverse problem more accurately. For example, resolution can be quantified from the resolution matrix rather than checkerboard tests; the covariance matrix can be calculated to evaluate the propagation of errors from data to model parameters; the L-curve method can be applied to determine a range of acceptable regularization schemes. We show how these exercises can be implemented efficiently on different hardware architectures.

  6. Monte Carlo simulation with the Gate software using grid computing

    International Nuclear Information System (INIS)

    Reuillon, R.; Hill, D.R.C.; Gouinaud, C.; El Bitar, Z.; Breton, V.; Buvat, I.

    2009-03-01

    Monte Carlo simulations are widely used in emission tomography, for protocol optimization, design of processing or data analysis methods, tomographic reconstruction, or tomograph design optimization. Monte Carlo simulations needing many replicates to obtain good statistical results can be easily executed in parallel using the 'Multiple Replications In Parallel' approach. However, several precautions have to be taken in the generation of the parallel streams of pseudo-random numbers. In this paper, we present the distribution of Monte Carlo simulations performed with the GATE software using local clusters and grid computing. We obtained very convincing results with this large medical application, thanks to the EGEE Grid (Enabling Grid for E-science), achieving in one week computations that could have taken more than 3 years of processing on a single computer. This work has been achieved thanks to a generic object-oriented toolbox called DistMe which we designed to automate this kind of parallelization for Monte Carlo simulations. This toolbox, written in Java is freely available on SourceForge and helped to ensure a rigorous distribution of pseudo-random number streams. It is based on the use of a documented XML format for random numbers generators statuses. (authors)

  7. Computer tomographic investigation of subcutaneous adipose tissue as an indicator of body composition

    DEFF Research Database (Denmark)

    McEvoy, Fintan; Madsen, Mads T.; Nielsen, Mai B.

    2009-01-01

    Background Modern computer tomography (CT) equipment can be used to acquire whole-body data from large animals such as pigs in minutes or less. In some circumstances, computer assisted analysis of the resulting image data can identify and measure anatomical features. The thickness of subcutaneous...... adipose tissue at a specific site measured by ultrasound, is used in the pig industry to assess adiposity and inform management decisions that have an impact on reproduction, food conversion performance and sow longevity. The measurement site, called "P2", is used throughout the industry. We propose...... and expressed as a proportion of total volume (fat-index). A computer algorithm was used to determined 10,201 subcutaneous adipose thickness measurements in each pig for each scan. From these data, sites were selected where correlation with fat-index was optimal. Results Image analysis correctly identified...

  8. A study of the decoding of multiple pinhole coded aperture RI tomographic images

    International Nuclear Information System (INIS)

    Hasegawa, Takeo; Kobayashi, Akitoshi; Nishiyama, Yutaka

    1980-01-01

    The authors constructed a Multiple Pinhole Coded Aperture (MPCA) and developed related decoding software. When simple coordinate transformation was performed, omission of points and shifting of counts occurred. By selecting various tomographic planes and collecting count for each tomographic depth from the shadowgram, a solution to these problems was found. The counts from the central portion of the tomographic image from the MPCA were incorrectly high, this was rectified by a correction function to improve the uniformity correction program of the γ-camera. Depth resolution of the tomographic image improved in proportion to the area encompassed by the pinhole configuration. An MPCA with a uniform arrangement of pinholes (e, g, pinholes in an arrangement parallel to the X-axis or the Y-axis) yielded decoded tomographic images of inferior quality. Optimum results were obtained with a ring-shaped arrangement yielding clinically applicable tomographic images even for large objects. (author)

  9. Initial results from the Donner 600 crystal positron tomograph

    International Nuclear Information System (INIS)

    Derenzo, S.E.; Huesman, R.H.; Cahoon, J.L.; Geyer, A.; Uber, D.; Vuletich, T.; Budinger, T.F.

    1986-10-01

    We describe a positron tomograph using a single ring of 600 close-packed 3 mm wide bismuth germanate (BGO) crystals coupled to 14 mm phototubes. The phototube preamplifier circuit derives a timing pulse from the first photoelectron, and sends it to address and coincidence circuits only if the integrated pulse height is within a pre-set window. The timing delays and pulse height windows for all 600 detectors and the coincidence timing windows are computer adjustable. An orbiting positron source is used for transmission measurements and a look-up table is used to reject scattered and random coincidences that do not pass through the source. Data can be acquired using a stationary mode for 1.57 mm lateral sampling or the two-position clam sampling mode for 0.79 mm lateral sampling. High maximum data rates are provided by 45 parallel coincidence circuits and 4 parallel histogram memory units. With two-position sampling and 1.57 mm bins, the reconstructed point spread function (PSF) of a 0.35 mm diam 22 Na wire source at the center of the tomograph is circular with 2.9 mm full-width at half-maximum (fwhm) and the PSF at a distance of 8 cm from the center is elliptical with a radial fwhm of 4.0 mm and tangential fwhm of 3.0 mm. 12 refs., 6 figs., 3 tabs

  10. Generalized Row-Action Methods for Tomographic Imaging

    DEFF Research Database (Denmark)

    Andersen, Martin Skovgaard; Hansen, Per Christian

    2014-01-01

    Row-action methods play an important role in tomographic image reconstruction. Many such methods can be viewed as incremental gradient methods for minimizing a sum of a large number of convex functions, and despite their relatively poor global rate of convergence, these methods often exhibit fast...... initial convergence which is desirable in applications where a low-accuracy solution is acceptable. In this paper, we propose relaxed variants of a class of incremental proximal gradient methods, and these variants generalize many existing row-action methods for tomographic imaging. Moreover, they allow...

  11. Computer tomographic investigations of cervical spinal stenosis

    Energy Technology Data Exchange (ETDEWEB)

    Rodiek, S.O.

    1983-10-01

    Computed tomography was applied in 29 patients with cervical spinal stenosis. In 8 cases there was a congenital narrowed spinal canal. In 18 cases we found dorsal spondylotic ridges of the vertebral bodies and in three cases an atlanto-dental dislocation. The complaints showed either radicular character or in case of myelopathy came out as para- and quadriplegia. In 25 cases the spinal sagittal diamter was a lot below a critical borderline of about 13 mm. The kind and localisation of the underlying process can be demonstrated very excellent by computed tomography.

  12. Computer tomographic investigations of cervical spinal stenosis

    International Nuclear Information System (INIS)

    Rodiek, S.O.

    1983-01-01

    Computed tomography was applied in 29 patients with cervical spinal stenosis. In 8 cases there was a congenital narrowed spinal canal. In 18 cases we found dorsal spondylotic ridges of the vertebral bodies and in three cases an atlanto-dental dislocation. The complaints showed either radicular character or in case of myelopathy came out as para- and quadriplegia. In 25 cases the spinal sagittal diamter was a lot below a critical borderline of about 13 mm. The kind and localisation of the underlying process can be demonstrated very excellent by computed tomography. (orig.) [de

  13. Computer tomographic findings in alcoholism

    Energy Technology Data Exchange (ETDEWEB)

    Agnoli, A.L.; Tzavaras, N.; Reisig, L. (Giessen Univ. (Germany, F.R.). Abt. Neuroradiologie)

    1980-05-01

    The normal variations in the size of the ventricular systems was determined on technically satisfactory computer tomograms in 275 patients who were psychologically and neurologically normal. Ages range from one to 80 years and the data classified in decades. A physiological increase in the width of the ventricular system was found after the 50sup(t)sup(h) year. The normal patients, who acted as a control group, were compared with 65 alcoholics. A significant increase in size (simple variance) was found in alcoholics after the fourth decade, as compared with normals. Correlation between the width of the ventricular system and cerebral function, and between liver damage and the ventricular system could not be established.

  14. A unique case of Turner syndrome accompanying prolactinoma and unexpected elongated styloid process: Clinical and cone-beam computed tomographic features

    International Nuclear Information System (INIS)

    Evlice, Burcu; Tatli, Ufuk; Yazicioglu, Iffet; Oztunc, Haluk; Evlice, Ahmet

    2013-01-01

    Turner syndrome (TS) is one of the most common chromosomal abnormalities, with an estimated frequency among female live births of 1/2,000-3,000. The syndrome is characterized by the partial or complete absence of one X chromosome (45,X karyotype). We reported a unique case of a 40-year-old woman with TS accompanying unexpected elongated styloid process specific to Eagle syndrome (ES) and followed up-prolactinoma. The present article is the first report to define the cone-beam computed tomographic (CBCT) features of TS accompanying ES. Patients with TS carry various risks that make treatment more complicated; thus advanced imaging techniques for proper treatment and follow-up are extremely important. In the light of CBCT examination, craniofacial abnormalities specific to TS and accompanying syndromes such as the crowding of teeth especially in the maxillary anterior region caused by maxillary narrowness, micrognatic maxilla and mandible, relative mandibular retrusion, malocclusion, open-bite, and an elongated styloid process (length of 32.7 mm) on the right side were illustrated in detail.

  15. A unique case of Turner syndrome accompanying prolactinoma and unexpected elongated styloid process: Clinical and cone-beam computed tomographic features

    Energy Technology Data Exchange (ETDEWEB)

    Evlice, Burcu; Tatli, Ufuk; Yazicioglu, Iffet; Oztunc, Haluk [Faculty of Dentistry, Cukurova University, Adana (Turkey); Evlice, Ahmet [Faculty of Medicine, Cukurova University, Adana (Turkey)

    2013-06-15

    Turner syndrome (TS) is one of the most common chromosomal abnormalities, with an estimated frequency among female live births of 1/2,000-3,000. The syndrome is characterized by the partial or complete absence of one X chromosome (45,X karyotype). We reported a unique case of a 40-year-old woman with TS accompanying unexpected elongated styloid process specific to Eagle syndrome (ES) and followed up-prolactinoma. The present article is the first report to define the cone-beam computed tomographic (CBCT) features of TS accompanying ES. Patients with TS carry various risks that make treatment more complicated; thus advanced imaging techniques for proper treatment and follow-up are extremely important. In the light of CBCT examination, craniofacial abnormalities specific to TS and accompanying syndromes such as the crowding of teeth especially in the maxillary anterior region caused by maxillary narrowness, micrognatic maxilla and mandible, relative mandibular retrusion, malocclusion, open-bite, and an elongated styloid process (length of 32.7 mm) on the right side were illustrated in detail.

  16. Differences in clinical features and computed tomographic findings between embolic and non-embolic acute ischemic stroke. A quantitative differential diagnosis

    International Nuclear Information System (INIS)

    Takano, Kentaro; Yamaguchi, Takenori; Minematsu, Kazuo; Sawada, Tohru; Omae, Teruo

    1998-01-01

    A diagnosis based on the presumed mechanism of stroke onset is useful for management strategies in acute ischemic stroke. Ninety-two patients with embolic (cardiac or artery-to-artery) and 107 with non-embolic (thrombotic or hemodynamic) stroke were diagnosed on strict cerebral angiographic criteria alone. To clearly discriminate between these two groups, the neurological and computed tomographic (CT) findings were then compared. Rapidity of onset, vomiting, urinary incontinence, level of consciousness, cervical bruit, anisocoria, tongue deviation, sensory disturbance, and CT findings (location of hypodense area, findings of brain edema and hemorrhagic transformation) were discriminatory factors between the two groups (p<0.01). According to these 11 items, we prepared a numerical table for quantitative differential diagnosis. A diagnostic accuracy of 98.9% for embolic and 87.9% for non-embolic stroke in internal verification, and 90.0% and 82.9%, respectively, in external verification was observed. The differences in clinical features and CT findings between embolic and non-embolic stroke may reflect the pathophysiological mechanisms of the occlusive process of cerebral artery as well as the extent and severity of ischemia. (author)

  17. Differences in clinical features and computed tomographic findings between embolic and non-embolic acute ischemic stroke. A quantitative differential diagnosis

    Energy Technology Data Exchange (ETDEWEB)

    Takano, Kentaro; Yamaguchi, Takenori; Minematsu, Kazuo; Sawada, Tohru; Omae, Teruo [National Cardiovascular Center, Suita, Osaka (Japan)

    1998-02-01

    A diagnosis based on the presumed mechanism of stroke onset is useful for management strategies in acute ischemic stroke. Ninety-two patients with embolic (cardiac or artery-to-artery) and 107 with non-embolic (thrombotic or hemodynamic) stroke were diagnosed on strict cerebral angiographic criteria alone. To clearly discriminate between these two groups, the neurological and computed tomographic (CT) findings were then compared. Rapidity of onset, vomiting, urinary incontinence, level of consciousness, cervical bruit, anisocoria, tongue deviation, sensory disturbance, and CT findings (location of hypodense area, findings of brain edema and hemorrhagic transformation) were discriminatory factors between the two groups (p<0.01). According to these 11 items, we prepared a numerical table for quantitative differential diagnosis. A diagnostic accuracy of 98.9% for embolic and 87.9% for non-embolic stroke in internal verification, and 90.0% and 82.9%, respectively, in external verification was observed. The differences in clinical features and CT findings between embolic and non-embolic stroke may reflect the pathophysiological mechanisms of the occlusive process of cerebral artery as well as the extent and severity of ischemia. (author)

  18. A tomograph VMEbus parallel processing data acquisition system

    International Nuclear Information System (INIS)

    Wilkinson, N.A.; Rogers, J.G.; Atkins, M.S.

    1989-01-01

    This paper describes a VME based data acquisition system suitable for the development of Positron Volume Imaging tomographs which use 3-D data for improved image resolution over slice-oriented tomographs. the data acquisition must be flexible enough to accommodate several 3-D reconstruction algorithms; hence, a software-based system is most suitable. Furthermore, because of the increased dimensions and resolution of volume imaging tomographs, the raw data event rate is greater than that of slice-oriented machines. These dual requirements are met by our data acquisition system. Flexibility is achieved through an array of processors connected over a VMEbus, operating asynchronously and in parallel. High raw data throughput is achieved using a dedicated high speed data transfer device available for the VMEbus. The device can attain a raw data rate of 2.5 million coincidence events per second for raw events which are 64 bits wide

  19. Construction of a positron emission tomograph with 2.4 mm detectors

    International Nuclear Information System (INIS)

    McIntyre, J.A.; Sprosst, R.L.; Wang, K.

    1986-01-01

    One-quarter of one ring of a positron tomograph has been constructed. The positron annihilation gamma rays are detected by polished plastic scintillators which direct scintillation light by internal reflection to optical fibers for transmission to the photo-multiplier tubes. By viewing each scintillator with four sets of optical fibers, the number of photomultipliers required for an eight ring tomograph with 1024 detectors per ring (2.4 mm wide detectors) can be reduced from 8192 to 288, and the cost of the tomograph reduced accordingly

  20. Tomographic findings of acute pulmonary toxoplasmosis in immunocompetent patients.

    Science.gov (United States)

    de Souza Giassi, Karina; Costa, Andre Nathan; Apanavicius, Andre; Teixeira, Fernando Bin; Fernandes, Caio Julio Cesar; Helito, Alfredo Salim; Kairalla, Ronaldo Adib

    2014-11-25

    Toxoplasmosis is one of the most common human zoonosis, and is generally benign in most of the individuals. Pulmonary involvement is common in immunocompromised subjects, but very rare in immunocompetents and there are scarce reports of tomographic findings in the literature. The aim of the study is to describe three immunocompetent patients diagnosed with acute pulmonary toxoplasmosis and their respective thoracic tomographic findings. Acute toxoplasmosis was diagnosed according to the results of serological tests suggestive of recent primary infection and the absence of an alternative etiology. From 2009 to 2013, three patients were diagnosed with acute respiratory failure secondary to acute toxoplasmosis. The patients were two female and one male, and were 38, 56 and 36 years old. Similarly they presented a two-week febrile illness and progressive dyspnea before admission. Laboratory tests demonstrated lymphocytosis, slight changes in liver enzymes and high inflammatory markers. Tomographic findings were bilateral smooth septal and peribronchovascular thickening (100%), ground-glass opacities (100%), atelectasis (33%), random nodules (33%), lymph node enlargement (33%) and pleural effusion (66%). All the patients improved their symptoms after treatment, and complete resolution of tomographic findings were found in the followup. These cases provide a unique description of the presentation and evolution of pulmonary tomographic manifestations of toxoplasmosis in immunocompetent patients. Toxoplasma pneumonia manifests with fever, dyspnea and a non-productive cough that may result in respiratory failure. In animal models, changes were described as interstitial pneumonitis with focal infiltrates of neutrophils that can finally evolve into a pattern of diffuse alveolar damage with focal necrosis. The tomographic findings are characterized as ground glass opacities, smooth septal and marked peribronchovascular thickening; and may mimic pulmonary congestion

  1. Three-Dimensional Segmentation of the Tumor in Computed Tomographic Images of Neuroblastoma

    OpenAIRE

    Deglint, Hanford J.; Rangayyan, Rangaraj M.; Ayres, Fábio J.; Boag, Graham S.; Zuffo, Marcelo K.

    2006-01-01

    Segmentation of the tumor in neuroblastoma is complicated by the fact that the mass is almost always heterogeneous in nature; furthermore, viable tumor, necrosis, and normal tissue are often intermixed. Tumor definition and diagnosis require the analysis of the spatial distribution and Hounsfield unit (HU) values of voxels in computed tomography (CT) images, coupled with a knowledge of normal anatomy. Segmentation and analysis of the tissue composition of the tumor can assist in quantitative ...

  2. Anatomical and computed tomographic analysis of the transcochlear and endoscopic transclival approaches to the petroclival region.

    Science.gov (United States)

    Mason, Eric; Van Rompaey, Jason; Carrau, Ricardo; Panizza, Benedict; Solares, C Arturo

    2014-03-01

    Advances in the field of skull base surgery aim to maximize anatomical exposure while minimizing patient morbidity. The petroclival region of the skull base presents numerous challenges for surgical access due to the complex anatomy. The transcochlear approach to the region provides adequate access; however, the resection involved sacrifices hearing and results in at least a grade 3 facial palsy. An endoscopic endonasal approach could potentially avoid negative patient outcomes while providing a desirable surgical window in a select patient population. Cadaveric study. Endoscopic access to the petroclival region was achieved through an endonasal approach. For comparison, a transcochlear approach to the clivus was performed. Different facets of the dissections, such as bone removal volume and exposed surface area, were computed using computed tomography analysis. The endoscopic endonasal approach provided a sufficient corridor to the petroclival region with significantly less bone removal and nearly equivalent exposure of the surgical target, thus facilitating the identification of the relevant anatomy. The lateral approach allowed for better exposure from a posterolateral direction until the inferior petrosal sinus; however, the endonasal approach avoided labyrinthine/cochlear destruction and facial nerve manipulation while providing an anteromedial viewpoint. The endonasal approach also avoided external incisions and cosmetic deficits. The endonasal approach required significant sinonasal resection. Endoscopic access to the petroclival region is a feasible approach. It potentially avoids hearing loss, facial nerve manipulation, and cosmetic damage. © 2013 The American Laryngological, Rhinological and Otological Society, Inc.

  3. Compact Positron Tomograph for Prostate Imaging

    National Research Council Canada - National Science Library

    Huber, Jennifer

    2004-01-01

    The goal of this project is to construct a functioning compact positron tomograph, whose geometry is optimized for detecting prostate tumors with molecular tracers such as 11Ccholine (carbon-11 choline...

  4. Compact Positron Tomograph for Prostate Imaging

    National Research Council Canada - National Science Library

    Huber, Jennifer S

    2005-01-01

    The goal of this project is to construct a functioning compact positron tomograph, whose geometry is optimized for detecting prostate tumors with molecular tracers such as 11Ccholine (carbon-11 choline...

  5. Use of a hybrid iterative reconstruction technique to reduce image noise and improve image quality in obese patients undergoing computed tomographic pulmonary angiography.

    Science.gov (United States)

    Kligerman, Seth; Mehta, Dhruv; Farnadesh, Mahmmoudreza; Jeudy, Jean; Olsen, Kathryn; White, Charles

    2013-01-01

    To determine whether an iterative reconstruction (IR) technique (iDose, Philips Healthcare) can reduce image noise and improve image quality in obese patients undergoing computed tomographic pulmonary angiography (CTPA). The study was Health Insurance Portability and Accountability Act compliant and approved by our institutional review board. A total of 33 obese patients (average body mass index: 42.7) underwent CTPA studies following standard departmental protocols. The data were reconstructed with filtered back projection (FBP) and 3 iDose strengths (iDoseL1, iDoseL3, and iDoseL5) for a total of 132 studies. FBP data were collected from 33 controls (average body mass index: 22) undergoing CTPA. Regions of interest were drawn at 6 identical levels in the pulmonary artery (PA), from the main PA to a subsegmental branch, in both the control group and study groups using each algorithm. Noise and attenuation were measured at all PA levels. Three thoracic radiologists graded each study on a scale of 1 (very poor) to 5 (ideal) by 4 categories: image quality, noise, PA enhancement, and "plastic" appearance. Statistical analysis was performed using an unpaired t test, 1-way analysis of variance, and linear weighted κ. Compared with the control group, there was significantly higher noise with FBP, iDoseL1, and iDoseL3 algorithms (Pnoise in the control group and iDoseL5 algorithm in the study group. Analysis within the study group showed a significant and progressive decrease in noise and increase in the contrast-to-noise ratio as the level of IR was increased (Pnoise and PA enhancement with increasing levels of iDose. The use of an IR technique leads to qualitative and quantitative improvements in image noise and image quality in obese patients undergoing CTPA.

  6. Paraquat-poisoning in the rabbit lungs: high resolution computed tomographic findings and pathologic correlation

    International Nuclear Information System (INIS)

    Lee, Kyung Soo; Kim, Eui Han; Lee, Byoung Ho; Kim, Kun Sang

    1992-01-01

    The authors evaluated high resolution computed tomographic (HRCT) findings of the isolated rabbit lungs with paraquat poisoning, and the findings were correlated with pathologic specimens. The purposes of this study are 1) to obtain the HRCT findings of the normal rabbit lung. 2) to find out if pulmonary pathology can be induced in rabbits by paraquat, and 3) to correlate the HRCT findings to those of pathology. Thirty rabbits were divided into three groups: group I included four control rabbits; group II included 16 rabbits given paraquat intraperitoneally (IP group); and group III included 10 rabbits given paraquat intravenously (IV group). The rabbits were sacrificed seven, 10, and 14 days after injection of various amount of paraquat, and then the lungs were isolated for HRCT and pathologic studies. Gross and microscopic findings of the three groups of control and paraquat-injected rabbit lungs were correlated with HRCT findings. Pulmonary congestion, mild thickening of alveolar walls and septae, and multifocal micro-atelectasis were the man pathologic findings of the lungs in both groups of the rabbits. Pulmonary hemorrhage was noted in five (31%) of 16 rabbits of IP group and three (30%) of 10 IV group. Pulmonary edema was seen in one rabbits (6%) of IP and four (40%) of IV group. Typical pulmonary fibrosis was seen in one rabbit of IP (6%) and IV (10%) group, respectively. There was no correlation between the amount of paraquat and frequency of the pulmonary pathology. Pulmonary fibrosis was seen at least one week after the paraquat injection. On HRCT, pulmonary hemorrhage and edema appeared as diffuse air-space consolidation and pulmonary fibrosis as linear or band-like opacities. However, minimal changes such as mild congestion

  7. Computer tomography of flows external to test models

    Science.gov (United States)

    Prikryl, I.; Vest, C. M.

    1982-01-01

    Computer tomographic techniques for reconstruction of three-dimensional aerodynamic density fields, from interferograms recorded from several different viewing directions were studied. Emphasis is on the case in which an opaque object such as a test model in a wind tunnel obscures significant regions of the interferograms (projection data). A method called the Iterative Convolution Method (ICM), existing methods in which the field is represented by a series expansions, and analysis of real experimental data in the form of aerodynamic interferograms are discussed.

  8. Preparation and tomographic reconstruction of an arbitrary single-photon path qubit

    International Nuclear Information System (INIS)

    Baek, So-Young; Kim, Yoon-Ho

    2011-01-01

    We report methods for preparation and tomographic reconstruction of an arbitrary single-photon path qubit. The arbitrary single-photon path qubit is prepared losslessly by passing the heralded single-photon state from spontaneous parametric down-conversion through variable beam splitter. Quantum state tomography of the single-photon path qubit is implemented by introducing path-projection measurements based on the first-order single-photon quantum interference. Using the state preparation and path-projection measurements methods for the single-photon path qubit, we demonstrate preparation and complete tomographic reconstruction of the single-photon path qubit with arbitrary purity. -- Highlights: → We report methods for preparation and tomographic reconstruction of an arbitrary single-photon path qubit. → We implement path-projection measurements based on the first-order single-photon quantum interference. → We demonstrate preparation and complete tomographic reconstruction of the single-photon path qubit with arbitrary purity.

  9. The tuning algorithms used by the Donner 600 crystal tomograph

    International Nuclear Information System (INIS)

    Moses, W.W.; Derenzo, S.E.; Geyer, A.B.; Huesman, R.H.; Uber, D.C.

    1989-01-01

    The authors describe the computer algorithms used to adjust the energy thresholds and timing delays in the Donner 600 Crystal Tomograph. These thresholds and delays are adjusted using 1890 computer controlled digital to analog converters (DAC's) and a orbiting positron source. The energy threshold for each crystal is adjusted by measuring the counting rate of each crystal-crystal coincidence as a function of the DAC settings that control a pulse height window for the crystal in question. The DAC settings that correspond to the 511 keV photopeak are noted, thus determining the conversion from DAC setting to energy, and allowing the DAC's to be set to any desired energy window. The DAC settings controlling the timing delay for each channel are systematically adjusted to maximize the overall event rate. As these 1890 adjustments are coupled, the authors discuss the convergence of the tuning algorithms, and also report on the photomultiplier tube gain and timing variations over a period of 18 months

  10. The tuning algorithms used by the Donner 600 Crystal Tomograph

    International Nuclear Information System (INIS)

    Moses, W.W.; Derenzo, S.E.; Geyer, A.B.; Huesman, R.H.; Uber, D.C.

    1988-11-01

    We describe the computer algorithms used to adjust the energy thresholds and timing delays in the Donner 600 Crystal Tomograph. These thresholds and delays are adjusted using 1890 computer controlled digital to analog converters (DAC's) and a orbiting positron source. The energy threshold for each crystal is adjusted by measuring the counting rate of each crystal-crystal coincidence as a function of the DAC settings that control a pulse height window for the crystal in question. The DAC settings that correspond to the 511 keV photopeak are noted, thus determining the conversion from DAC setting to energy, and allowing the DAC's to be set to any desired energy window. The DAC settings controlling the timing delay for each channel are systematically adjusted to maximize the overall event rate. As these 1890 adjustments are coupled, we discuss the convergence of the tuning algorithms, and also report on the photomultiplier tube gain and timing variations over a period of 18 months. 7 refs., 6 figs

  11. Computational movement analysis

    CERN Document Server

    Laube, Patrick

    2014-01-01

    This SpringerBrief discusses the characteristics of spatiotemporal movement data, including uncertainty and scale. It investigates three core aspects of Computational Movement Analysis: Conceptual modeling of movement and movement spaces, spatiotemporal analysis methods aiming at a better understanding of movement processes (with a focus on data mining for movement patterns), and using decentralized spatial computing methods in movement analysis. The author presents Computational Movement Analysis as an interdisciplinary umbrella for analyzing movement processes with methods from a range of fi

  12. Electronics for the Donner 600-Crystal Positron Tomograph

    International Nuclear Information System (INIS)

    Cahoon, J.L.; Huesman, R.H.; Derenzo, S.E.; Geyer, A.B.; Uber, D.C.; Turko, B.T.; Budinger, T.F.

    1985-10-01

    The data acquisition system, designed for the Donner 600-Crystal Positron Tomograph, is described. Coincidence timing resolution of less than five nanoseconds full width at half maximum and data rates in excess of one million events per second are achieved by using high-speed emitter coupled logic circuits, first-in first-out memory to derandomize data flow, and parallel architecture to increase throughput. These data rates allow the acquisition of adequate transmission data in a reasonable amount of time. Good timing resolution minimizes accidental coincidences and permits data rates greater than 100,000 image-forming events per second for high-speed dynamic emission tomography. Additional scatter and accidental rejection are accomplished for transmission data by using an orbiting source and a look-up table for valid events. Calibration of this complex electronic system is performed automatically under computer control. 4 refs., 5 figs

  13. Detection of intra-cardiac thrombi and congestive heart failure in cats using computed tomographic angiography.

    Science.gov (United States)

    Vititoe, Kyle P; Fries, Ryan C; Joslyn, Stephen; Selmic, Laura E; Howes, Mark; Vitt, Jordan P; O'Brien, Robert T

    2018-04-16

    Arterial thromboembolism is a life-threatening condition in cats most commonly secondary to cardiac disease. Echocardiography is the reference standard to evaluate for presence of a thrombus. In humans, computed tomographic (CT) angiography is becoming widely used to detect left atrial thrombi precluding the use of sedation. The purpose of this prospective, controlled, methods comparison pilot study was threefold: (1) describe new CT angiography protocol used in awake cats with cardiac disease and congestive heart failure; (2) determine accuracy of continuous and dynamic acquisition CT angiography to identify and characterize cardiac thrombi from spontaneous echocardiographic contrast using transthoracic echocardiography as our reference standard; (3) identify known negative prognostic factors and comorbidities of the thorax that CT angiography may provide that complement or supersede echocardiographic examination. Fourteen cats with heart disease were recruited; 7 with thrombi and 7 with spontaneous echocardiographic contrast. Echocardiography and awake CT angiography were performed using a microdose of contrast. Six of 7 thrombi were identified on CT angiography as filling defects by at least one reviewer within the left auricle (n = 6) and right heart (n = 1). Highest sensitivity (71.4%) was in continuous phase and highest specificity (85.7%) was in dynamic studies with fair to moderate interobserver agreement (0.38 and 0.44). CT angiography identified prognostic cardiac information (left atrial enlargement, congestive heart failure, arterial thromboembolism) and comorbidities (suspected idiopathic pulmonary fibrosis, asthma). This study indicates CT angiography can readily identify cardiac thrombi, important prognostic information and comorbidities, and can be safely performed in cats with cardiac disease and congestive heart failure. © 2018 American College of Veterinary Radiology.

  14. Computed tomography of cystic pancreatic fibrosis

    International Nuclear Information System (INIS)

    Brachlow, M.; Zaunbauer, W.; Haertel, M.

    1984-01-01

    The computer tomographic appearances of atrophic and lipomatous degeneration of the pancreas in cystic pancreatic fibrosis are described. CT exploration of the pancreas in recommended, particularly in differential diagnostic aspects of cystic fibrosis. (orig.) [de

  15. Application of the FDK algorithm for multi-slice tomographic image reconstruction; Aplicacao do algoritmo FDK para a reconstrucao de imagens tomograficas multicortes

    Energy Technology Data Exchange (ETDEWEB)

    Costa, Paulo Roberto, E-mail: pcosta@if.usp.b [Universidade de Sao Paulo (IFUSP), SP (Brazil). Inst. de Fisica. Dept. de Fisica Nuclear; Araujo, Ericky Caldas de Almeida [Fine Image Technology, Sao Paulo, SP (Brazil)

    2010-08-15

    This work consisted on the study and application of the FDK (Feldkamp- Davis-Kress) algorithm for tomographic image reconstruction using cone-beam geometry, resulting on the implementation of an adapted multi-slice computed tomography system. For the acquisition of the projections, a rotating platform coupled to a goniometer, an X-ray equipment and a digital image detector charge-coupled device type were used. The FDK algorithm was implemented on a computer with a Pentium{sup R} XEON{sup TM} 3.0 processor, which was used for the reconstruction process. Initially, the original FDK algorithm was applied considering only the ideal physical conditions in the measurement process. Then some artifacts corrections related to the projections measurement process were incorporated. The implemented MSCT system was calibrated. A specially designed and manufactured object with a known linear attenuation coefficient distribution ({mu}(r)) was used for this purpose. Finally, the implemented MSCT system was used for multi-slice tomographic reconstruction of an inhomogeneous object, whose distribution {mu}(r) was unknown. Some aspects of the reconstructed images were analyzed to assess the robustness and reproducibility of the system. During the system calibration, a linear relationship between CT number and linear attenuation coefficients of materials was verified, which validate the application of the implemented multi-slice tomographic system for the characterization of linear attenuation coefficients of distinct several objects. (author)

  16. Original circuitry for TOHR tomograph

    International Nuclear Information System (INIS)

    Cuzon, J.C.; Pinot, L.

    1999-01-01

    Having industrialization in mind, a specific electronics for a high resolution tomograph is designed out of the usual standards of nuclear physics. All the information are converted in the time domain and a fast processor, in front of the data acquisition, carries out the time and energy coincidences. (authors)

  17. Non-rigid registration of tomographic images with Fourier transforms

    International Nuclear Information System (INIS)

    Osorio, Ar; Isoardi, Ra; Mato, G

    2007-01-01

    Spatial image registration of deformable body parts such as thorax and abdomen has important medical applications, but at the same time, it represents an important computational challenge. In this work we propose an automatic algorithm to perform non-rigid registration of tomographic images using a non-rigid model based on Fourier transforms. As a measure of similarity, we use the correlation coefficient, finding that the optimal order of the transformation is n = 3 (36 parameters). We apply this method to a digital phantom and to 7 pairs of patient images corresponding to clinical CT scans. The preliminary results indicate a fairly good agreement according to medical experts, with an average registration error of 2 mm for the case of clinical images. For 2D images (dimensions 512x512), the average running time for the algorithm is 15 seconds using a standard personal computer. Summarizing, we find that intra-modality registration of the abdomen can be achieved with acceptable accuracy for slight deformations and can be extended to 3D with a reasonable execution time

  18. Computed tomographic findings in pancreatic pathology

    International Nuclear Information System (INIS)

    Frija, J.; Laval-Jeantet, M.; Larde, D.; Mathieu, D.

    1986-01-01

    Computed tomography (CT) is actually the most suitable examination for the study of the pancreas. The evolution during the life of its thickness is studied. For the same age group pancreas sharpens from the head to the body and the tail. Pancreas progressively sharpens during the life. The comparison of the efficacy of the other imaging modalities is studied. The indications of the radiological examinations of the pancreas are evaluated during acute and chronic pancreatitis, pseudocysts, adenocarcinoma of the pancreas and endocrine tumors of the pancreas [fr

  19. Evaluation of valvular heart diseases with computed tomography

    International Nuclear Information System (INIS)

    Tomoda, Haruo; Hoshiai, Mitsumoto; Matsuyama, Seiya

    1982-01-01

    Forty-two patients with valvular heart diseases were studied with a third-generation computed tomographic system. The cardiac chambers (the atria and ventricles) were evaluated semiquantitatively, and valvular calcification was easily detected with computed tomography. Computed tomography was most valuable in revealing left atrial thrombi which were not identified by other diagnostic procedures in some cases. (author)

  20. A tomograph VMEbus parallel processing data acquisition system

    International Nuclear Information System (INIS)

    Atkins, M.S.; Wilkinson, N.A.; Rogers, J.G.

    1988-11-01

    This paper describes a VME based data acquisition system suitable for the development of Positron Volume Imaging tomographs which use 3-D data for improved image resolution over slice-oriented tomographs. The data acquisition must be flexible enough to accommodate several 3-D reconstruction algorithms; hence, a software-based system is most suitable. Furthermore, because of the increased dimensions and resolution of volume imaging tomographs, the raw data event rate is greater than that of slice-oriented machines. These dual requirements are met by our data acquisition systems. Flexibility is achieved through an array of processors connected over a VMEbus, operating asynchronously and in parallel. High raw data throughput is achieved using a dedicated high speed data transfer device available for the VMEbus. The device can attain a raw data rate of 2.5 million coincidence events per second for raw events per second for raw events which are 64 bits wide. Real-time data acquisition and pre-processing requirements can be met by about forty 20 MHz Motorola 68020/68881 processors

  1. Post-processing methods of rendering and visualizing 3-D reconstructed tomographic images

    Energy Technology Data Exchange (ETDEWEB)

    Wong, S.T.C. [Univ. of California, San Francisco, CA (United States)

    1997-02-01

    The purpose of this presentation is to discuss the computer processing techniques of tomographic images, after they have been generated by imaging scanners, for volume visualization. Volume visualization is concerned with the representation, manipulation, and rendering of volumetric data. Since the first digital images were produced from computed tomography (CT) scanners in the mid 1970s, applications of visualization in medicine have expanded dramatically. Today, three-dimensional (3D) medical visualization has expanded from using CT data, the first inherently digital source of 3D medical data, to using data from various medical imaging modalities, including magnetic resonance scanners, positron emission scanners, digital ultrasound, electronic and confocal microscopy, and other medical imaging modalities. We have advanced from rendering anatomy to aid diagnosis and visualize complex anatomic structures to planning and assisting surgery and radiation treatment. New, more accurate and cost-effective procedures for clinical services and biomedical research have become possible by integrating computer graphics technology with medical images. This trend is particularly noticeable in current market-driven health care environment. For example, interventional imaging, image-guided surgery, and stereotactic and visualization techniques are now stemming into surgical practice. In this presentation, we discuss only computer-display-based approaches of volumetric medical visualization. That is, we assume that the display device available is two-dimensional (2D) in nature and all analysis of multidimensional image data is to be carried out via the 2D screen of the device. There are technologies such as holography and virtual reality that do provide a {open_quotes}true 3D screen{close_quotes}. To confine the scope, this presentation will not discuss such approaches.

  2. Post-processing methods of rendering and visualizing 3-D reconstructed tomographic images

    International Nuclear Information System (INIS)

    Wong, S.T.C.

    1997-01-01

    The purpose of this presentation is to discuss the computer processing techniques of tomographic images, after they have been generated by imaging scanners, for volume visualization. Volume visualization is concerned with the representation, manipulation, and rendering of volumetric data. Since the first digital images were produced from computed tomography (CT) scanners in the mid 1970s, applications of visualization in medicine have expanded dramatically. Today, three-dimensional (3D) medical visualization has expanded from using CT data, the first inherently digital source of 3D medical data, to using data from various medical imaging modalities, including magnetic resonance scanners, positron emission scanners, digital ultrasound, electronic and confocal microscopy, and other medical imaging modalities. We have advanced from rendering anatomy to aid diagnosis and visualize complex anatomic structures to planning and assisting surgery and radiation treatment. New, more accurate and cost-effective procedures for clinical services and biomedical research have become possible by integrating computer graphics technology with medical images. This trend is particularly noticeable in current market-driven health care environment. For example, interventional imaging, image-guided surgery, and stereotactic and visualization techniques are now stemming into surgical practice. In this presentation, we discuss only computer-display-based approaches of volumetric medical visualization. That is, we assume that the display device available is two-dimensional (2D) in nature and all analysis of multidimensional image data is to be carried out via the 2D screen of the device. There are technologies such as holography and virtual reality that do provide a open-quotes true 3D screenclose quotes. To confine the scope, this presentation will not discuss such approaches

  3. Correction of ring artifacts in X-ray tomographic images

    DEFF Research Database (Denmark)

    Lyckegaard, Allan; Johnson, G.; Tafforeau, P.

    2011-01-01

    Ring artifacts are systematic intensity distortions located on concentric circles in reconstructed tomographic X-ray images. When using X-ray tomography to study for instance low-contrast grain boundaries in metals it is crucial to correct for the ring artifacts in the images as they may have...... the same intensity level as the grain boundaries and thus make it impossible to perform grain segmentation. This paper describes an implementation of a method for correcting the ring artifacts in tomographic X-ray images of simple objects such as metal samples where the object and the background...... are separable. The method is implemented in Matlab, it works with very little user interaction and may run in parallel on a cluster if applied to a whole stack of images. The strength and robustness of the method implemented will be demonstrated on three tomographic X-ray data sets: a mono-phase β...

  4. Computed Tomographic Angiography of the Pancreas in Cats with Chronic Diabetes Mellitus Compared to Normal Cats.

    Science.gov (United States)

    Secrest, S; Sharma, A; Bugbee, A

    2018-03-02

    Diabetes mellitus (DM) is a common endocrinopathy in cats. No known diagnostic test or patient characteristic at the time of diagnosis can predict likely disease course, unlike in people in whom computed tomographic angiography (CTA) is used. No published data exist regarding the CTA appearance of the pancreas in cats with DM, and thus, it is unknown what if any CTA variables should be further assessed for associations with pancreatic endocrine function. A significant difference in pancreatic attenuation, volume, and size will be identified between normal cats and those with chronic DM on CTA. Ten healthy control cats and 15 cats with naturally occurring DM present for >12 months. Prospective cross-sectional study comparing pancreatic attenuation, enhancement pattern, size, volume, pancreatic volume-to-body weight ratio (V:BW), pancreatic arterial: portal phase ratio (A:P), time-to-arterial enhancement, and time-to-peak portal enhancement on CTA between sedated healthy control cats and those with chronic DM. The pancreas in cats with chronic DM was significantly larger, had higher volume, higher V:BW, and shorter time-to-peak portal enhancement on CTA when compared to normal cats. Peak portal enhancement time, pancreatic size, pancreatic volume, and V:BW can be used to differentiate normal sedated cats from those with chronic DM by CTA. These variables warrant further investigation to identify possible associations with endocrine function. Copyright © 2017 The Authors. Journal of Veterinary Internal Medicine published by Wiley Periodicals, Inc. on behalf of the American College of Veterinary Internal Medicine.

  5. Quantification in single photon emission computed tomography (SPECT)

    International Nuclear Information System (INIS)

    Buvat, Irene

    2005-01-01

    The objective of this lecture is to understand the possibilities and limitations of the quantitative analysis of single photon emission computed tomography (SPECT) images. It is also to identify the conditions to be fulfilled to obtain reliable quantitative measurements from images. Content: 1 - Introduction: Quantification in emission tomography - definition and challenges; quantification biasing phenomena; 2 - quantification in SPECT, problems and correction methods: Attenuation, scattering, un-stationary spatial resolution, partial volume effect, movement, tomographic reconstruction, calibration; 3 - Synthesis: actual quantification accuracy; 4 - Beyond the activity concentration measurement

  6. Clinical and high-resolution computed tomographic findings in five patients with pulmonary tuberculosis who developed respiratory failure following chemotherapy

    International Nuclear Information System (INIS)

    Akira, Masanori; Sakatani, Mitsunori

    2001-01-01

    AIM: The purpose of this study was to describe the clinical and high-resolution computed tomographic (HRCT) findings in patients with pulmonary tuberculosis who developed respiratory failure after starting chemotherapy. MATERIALS AND METHODS: The clinical records, chest radiographs, and HRCT findings in five patients with non-miliary pulmonary tuberculosis who developed respiratory failure after starting chemotherapy were reviewed. RESULTS: Chest radiographs taken early in the course of acute respiratory failure showed progression of the original lesions with (n = 4) or without (n = 1) new areas of opacity away from the site of the original lesions. HRCT demonstrated widespread ground-glass attenuation with a reticular pattern as well as segmental or lobar consolidation with cavitation and nodules, consistent with active tuberculous foci in all five cases. Prominent interlobular septal thickening was seen in two cases. Four of the five patients had received corticosteroids. Of these five, two died and three recovered with continued corticosteroid therapy. Transbronchial biopsy in three cases showed evidence of acute alveolar damage. CONCLUSION: In selected patients with tuberculosis who develop respiratory failure following the initiation of antituberculous therapy, HRCT may be a helpful adjunct to clinical evaluation in differentiating hypersensitivity reactions (presumed to be due to the release of mycobacterial antigens) from other pulmonary complications. Akira, M. and Sakatani, M. (2001)

  7. Soil structure restoration by wet/dry cycles assessed by computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Pires, L.F. [Univ. of Sao Paulo, Center for Nuclear Energy in Agriculture, Piracicaba, Sao Paulo (Brazil)

    2005-07-01

    Some studies have shown that soil structures can be restored through the sequence of wetting and drying cycles. These cycles causes changes in the soil pore system, which is very important to agriculture, because directly affect plant growth by root penetration, retention and movement of water and gases. The aim of this study was to follow by gamma-ray computed tomography (CT) the effect of soil wetting/drying process on the soil structure repairing of samples collected in cylinders. A first-generation tomograph with an {sup 241}Am source and a 7.62 x 7.62 cm NaI(Tl) scintillation crystal detector coupled to a photomultiplier tube was employed. Image analysis and tomographic unit profiles show that CT can provide an insight to sample structure restoration, which helps to have a better comprehension of soil physical hydraulic phenomena. (author)

  8. Soil structure restoration by wet/dry cycles assessed by computed tomography

    International Nuclear Information System (INIS)

    Pires, L.F.

    2005-01-01

    Some studies have shown that soil structures can be restored through the sequence of wetting and drying cycles. These cycles causes changes in the soil pore system, which is very important to agriculture, because directly affect plant growth by root penetration, retention and movement of water and gases. The aim of this study was to follow by gamma-ray computed tomography (CT) the effect of soil wetting/drying process on the soil structure repairing of samples collected in cylinders. A first-generation tomograph with an 241 Am source and a 7.62 x 7.62 cm NaI(Tl) scintillation crystal detector coupled to a photomultiplier tube was employed. Image analysis and tomographic unit profiles show that CT can provide an insight to sample structure restoration, which helps to have a better comprehension of soil physical hydraulic phenomena. (author)

  9. The use of intraosseous needles for injection of contrast media for computed tomographic angiography of the thoracic aorta.

    Science.gov (United States)

    Winkler, Michael; Talley, Cynthia; Woodward, Connor; Kingsbury, Alexander; Appiah, Frank; Elbelasi, Hossam; Landwher, Kevin; Li, Xingzhe; Fleischmann, Dominik

    The objective of this study is to evaluate the safety and quality of computed tomographic angiography of the thoracic aorta (CTA-TA) exams performed using intraosseous needle intravenous access (ION-IVA) for contrast media injection (CMI). All CTA-TA exams at the study institution performed between 1/1/2013 and 8/14/2015 were reviewed retrospectively to identify those exams which had been performed using ION-IVA (ION-exams). ION-exams were then analyzed to determine aortic attenuation and contrast-to-noise ratio (CNR). Linear regression was used to determine how injection rate and other variables affected image quality for ION-exams. Patient electronic medical records were reviewed to identify any adverse events related to CTA-TA or ION-IVA. 17 (∼0.2%) of 7401 exams were ION-exams. ION-exam CMI rates varied between 2.5 and 4 ml/s. Mean attenuation was 312 HU (SD 88 HU) and mean CNR was 25 (SD 9.9). A strong positive linear association between attenuation and injection rate was found. No immediate or delayed complications related to the ION-exams, or intraosseous needle use in general, occurred. For CTA-TA, ION-IVA appears to be a safe and effective route for CMI at rates up to 4 ml/s. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

  10. Computed tomographic cephalometric analysis of chinese patients with obstructive sleep apnoea

    International Nuclear Information System (INIS)

    Peh, W.C.G.; Chu, F.S.K.; Ip, M.S.M.; Chung, K.-F.

    2000-01-01

    Variations of craniofacial and upper airway structures are recognized to contribute to the phenomenon of obstructive sleep apnoea (OSA). Most previous cephalometric studies were performed using erect lateral radiographs in Caucasian patients. The present project aims to determine cephalometric measurements, utilizing CT, in normal Chinese subjects and in Chinese patients with OSA. Computed tomography of 25 patients with OSA (proven using overnight polysomnography), and of 25 age-, sex-, height-, bodyweight- and body mass index (BMI)-matched control subjects were prospectively performed. Thirteen standard bony and soft-tissue measurements were obtained from the CT lateral scout view of the head and neck, taken with each subject in the neutral supine position. The cross-sectional area was calculated at two axial levels (velopharynx and hypopharynx). The measurements in the two groups, OSA and control subjects, were compared. The measurements for hyoid position (P=0.00), nasal cavity length (P=0.01), mandibular prognathism (P = 0.05), tongue size (P = 0.02), oropharyngeal airway space (P = 0.02), posterior tongue airway space (P = 0.04) and cross-sectional areas at the level of the velopharynx (P = 0.00) and hypopharynx (P = 0.01) differed significantly between the two groups. In conclusion, CT cephalometric measurements show that certain anatomical variations in the head and neck are likely to contribute to the pathogenesis of OSA in Chinese patients. Copyright (1999) Blackwell Science Pty Ltd

  11. Computer tomographic anatomy of the neck

    International Nuclear Information System (INIS)

    Koenig, R.

    1984-01-01

    The structures in the neck which can be recognised by computer tomography, and their course, is described. The cartilagenous larynx and trachea, the oesophagus, thyroid, sternocleidomastoid muscle, common carotid arteries and internal jugular veins can be recognised regularly. In addition, one can identify smaller muscles, vessels and nerves, such as the sterno-hyoid, omo-hyoid, anterior and medial scalenus muscles, the superior and inferior thyroid arteries and the suprascapular, internal thoracic and vertebral arteries, the thyro-cervical trunk and the vagus and phrenic nerves. An accurate knowledge of the anatomy is essential for the recognition of enlarged parathyroid glands. (orig.) [de

  12. Computer tomographic anatomy of the neck

    Energy Technology Data Exchange (ETDEWEB)

    Koenig, R.

    1984-01-01

    The structures in the neck which can be recognised by computer tomography, and their course, is described. The cartilagenous larynx and trachea, the oesophagus, thyroid, sternocleidomastoid muscle, common carotid arteries and internal jugular veins can be recognised regularly. In addition, one can identify smaller muscles, vessels and nerves, such as the sterno-hyoid, omo-hyoid, anterior and medial scalenus muscles, the superior and inferior thyroid arteries and the suprascapular, internal thoracic and vertebral arteries, the thyro-cervical trunk and the vagus and phrenic nerves. An accurate knowledge of the anatomy is essential for the recognition of enlarged parathyroid glands.

  13. An introduction to emission computed tomography

    International Nuclear Information System (INIS)

    Williams, E.D.

    1985-01-01

    This report includes salient features of the theory and an examination of practical considerations for someone who is using or introducing tomography, selecting equipment for it or wishing to develop a clinical application. Emphasis is on gamma camera tomography. The subject is dealt with under the following headings: emission computed and gamma camera tomography and the relationship to other medical imaging techniques, the tomographic reconstruction technique theory, rotating gamma camera tomography, attenuation correction and quantitative reconstruction, other single photon tomographic techniques, positron tomography, image display, clinical application of single photon and positron tomography, and commercial systems for SPECT. Substantial bibliography. (U.K.)

  14. Computed 3D visualisation of an extinct cephalopod using computer tomographs.

    Science.gov (United States)

    Lukeneder, Alexander

    2012-08-01

    The first 3D visualisation of a heteromorph cephalopod species from the Southern Alps (Dolomites, northern Italy) is presented. Computed tomography, palaeontological data and 3D reconstructions were included in the production of a movie, which shows a life reconstruction of the extinct organism. This detailed reconstruction is according to the current knowledge of the shape and mode of life as well as habitat of this animal. The results are based on the most complete shell known thus far of the genus Dissimilites . Object-based combined analyses from computed tomography and various computed 3D facility programmes help to understand morphological details as well as their ontogentical changes in fossil material. In this study, an additional goal was to show changes in locomotion during different ontogenetic phases of such fossil, marine shell-bearing animals (ammonoids). Hence, the presented models and tools can serve as starting points for discussions on morphology and locomotion of extinct cephalopods in general, and of the genus Dissimilites in particular. The heteromorph ammonoid genus Dissimilites is interpreted here as an active swimmer of the Tethyan Ocean. This study portrays non-destructive methods of 3D visualisation applied on palaeontological material, starting with computed tomography resulting in animated, high-quality video clips. The here presented 3D geometrical models and animation, which are based on palaeontological material, demonstrate the wide range of applications, analytical techniques and also outline possible limitations of 3D models in earth sciences and palaeontology. The realistic 3D models and motion pictures can easily be shared amongst palaeontologists. Data, images and short clips can be discussed online and, if necessary, adapted in morphological details and motion-style to better represent the cephalopod animal.

  15. Computed 3D visualisation of an extinct cephalopod using computer tomographs

    Science.gov (United States)

    Lukeneder, Alexander

    2012-08-01

    The first 3D visualisation of a heteromorph cephalopod species from the Southern Alps (Dolomites, northern Italy) is presented. Computed tomography, palaeontological data and 3D reconstructions were included in the production of a movie, which shows a life reconstruction of the extinct organism. This detailed reconstruction is according to the current knowledge of the shape and mode of life as well as habitat of this animal. The results are based on the most complete shell known thus far of the genus Dissimilites. Object-based combined analyses from computed tomography and various computed 3D facility programmes help to understand morphological details as well as their ontogentical changes in fossil material. In this study, an additional goal was to show changes in locomotion during different ontogenetic phases of such fossil, marine shell-bearing animals (ammonoids). Hence, the presented models and tools can serve as starting points for discussions on morphology and locomotion of extinct cephalopods in general, and of the genus Dissimilites in particular. The heteromorph ammonoid genus Dissimilites is interpreted here as an active swimmer of the Tethyan Ocean. This study portrays non-destructive methods of 3D visualisation applied on palaeontological material, starting with computed tomography resulting in animated, high-quality video clips. The here presented 3D geometrical models and animation, which are based on palaeontological material, demonstrate the wide range of applications, analytical techniques and also outline possible limitations of 3D models in earth sciences and palaeontology. The realistic 3D models and motion pictures can easily be shared amongst palaeontologists. Data, images and short clips can be discussed online and, if necessary, adapted in morphological details and motion-style to better represent the cephalopod animal.

  16. Improved diagnostic performance of exercise thallium-201 single photon emission computed tomography over planar imaging in the diagnosis of coronary artery disease: a receiver operating characteristic analysis

    International Nuclear Information System (INIS)

    Fintel, D.J.; Links, J.M.; Brinker, J.A.; Frank, T.L.; Parker, M.; Becker, L.C.

    1989-01-01

    Qualitative interpretation of tomographic and planar scintigrams, a five point rating scale and receiver operating characteristic analysis were utilized to compare single photon emission computed tomography and conventional planar imaging of myocardial thallium-201 uptake in the accuracy of the diagnosis of coronary artery disease and individual vessel involvement. One hundred twelve patients undergoing cardiac catheterization and 23 normal volunteers performed symptom-limited treadmill exercise, followed by stress and redistribution imaging by both tomographic and planar techniques, with the order determined randomly. Paired receiver operating characteristic curves revealed that single photon emission computed tomography was more accurate than planar imaging over the entire range of decision thresholds for the overall detection and exclusion of coronary artery disease and involvement of the left anterior descending and left circumflex coronary arteries. Tomography offered relatively greater advantages in male patients and in patients with milder forms of coronary artery disease, who had no prior myocardial infarction, only single vessel involvement or no lesion greater than or equal to 50 to 69%. Tomography did not appear to provide improved diagnosis in women or in detection of disease in the right coronary artery. Although overall detection of coronary artery disease was not improved in patients with prior myocardial infarction, tomography provided improved identification of normal and abnormal vascular regions. These results indicate that single photon emission computed tomography provides improved diagnostic performance compared with planar imaging in many clinical subgroups

  17. Tomographic findings of lobar consolidation in primary pulmonary tuberculosis

    International Nuclear Information System (INIS)

    Pereira, Bruno Alberto Falcao; Macedo, Solange Goncalves David de; Penna, Claudia Renata Rezende

    2009-01-01

    Objective: To describe tomographic findings of lobar consolidation as early manifestation of primary pulmonary tuberculosis. Materials and methods: The present study was developed at Hospital Municipal Jesus, Rio de Janeiro, RJ, Brazil, in the period between 2002 and 2006, retrospectively evaluating tomographic findings in four children aged from 3 to 14 months with lobar consolidation as an early manifestation of primary pulmonary tuberculosis. Results: The most frequently found radiological pattern was lobar consolidation with calcifications, cavitation and intermingle necrotic areas, associated with bulging fissure. Signs of bronchogenic dissemination and lymph node enlargement were observed in all of the four children. Consolidation with a pseudotumor aspect and masslike effect was observed in one case. Conclusion: The cases included in the present study have demonstrated that primary pulmonary tuberculosis manifested as lobar consolidation presents typical tomographic images such as cavitation, hypodense areas and calcifications intermingled with consolidation. The association with lymph node enlargement with central necrosis and signs of bronchogenic dissemination reinforce the diagnosis of tuberculosis. (author)

  18. On the estimation of wall pressure coherence using time-resolved tomographic PIV

    Science.gov (United States)

    Pröbsting, Stefan; Scarano, Fulvio; Bernardini, Matteo; Pirozzoli, Sergio

    2013-07-01

    Three-dimensional time-resolved velocity field measurements are obtained using a high-speed tomographic Particle Image Velocimetry (PIV) system on a fully developed flat plate turbulent boundary layer for the estimation of wall pressure fluctuations. The work focuses on the applicability of tomographic PIV to compute the coherence of pressure fluctuations, with attention to the estimation of the stream and spanwise coherence length. The latter is required for estimations of aeroacoustic noise radiation by boundary layers and trailing edge flows, but is also of interest for vibro-structural problems. The pressure field is obtained by solving the Poisson equation for incompressible flows, where the source terms are provided by time-resolved velocity field measurements. Measured 3D velocity data is compared to results obtained from planar PIV, and a Direct Numerical Simulation (DNS) at similar Reynolds number. An improved method for the estimation of the material based on a least squares estimator of the velocity derivative along a particle trajectory is proposed and applied. Computed surface pressure fluctuations are further verified by means of simultaneous measurements by a pinhole microphone and compared to the DNS results and a semi-empirical model available from literature. The correlation coefficient for the reconstructed pressure time series with respect to pinhole microphone measurements attains approximately 0.5 for the band-pass filtered signal over the range of frequencies resolved by the velocity field measurements. Scaled power spectra of the pressure at a single point compare favorably to the DNS results and those available from literature. Finally, the coherence of surface pressure fluctuations and the resulting span- and streamwise coherence lengths are estimated and compared to semi-empirical models and DNS results.

  19. Radiographic and tomographic study of the elbow joint in dogs; Avaliacao morfologica e morfometrica da articulacao umerorradioulnar em caes atraves de exames radiograficos e por tomografia computadorizada

    Energy Technology Data Exchange (ETDEWEB)

    Sendyk-Grunkraut, Alessandra; Martin, Claudia M.; Souza, Alexandre N.A.; Patricio, Geni Cristina F.; Lorigados, Carla A.B.; Matera, Julia M.; Fonseca-Pinto, Ana C.B.C., E-mail: anacarol@usp.br [Universidade de Sao Paulo (FMVZ/USP), SP (Brazil). Faculdade de Medicina Veterinaria e Zootecnia

    2017-02-15

    Elbow dysplasia disease includes an united anconeal process, fragmented medial coronoid process, osteochondrosis of humeral trochlea, articular incongruity and degenerative joint disease. The aim of this study was to present detailed morphologic and morphometric aspects of the elbow joint in dog in clinical and correlate with radiographic and tomographic (CT) exam. Inter-observer variation for articular incongruity measurements by CT, comparative analysis in the radiographic exam, angle in ulnar notch and its comparative analysis between radiographic and tomographic agreement examination in 44 elbow of dogs with different ages were evaluated. The statistics analyses included the kappa coefficient and interclass correlation and Fischer's test and McNemar's test. It was evidenced that individual performance of each radiographic incidence had poor agreement with the tomographic exam, suggesting that the accomplishment of more than two radiograph views are needed. There was no agreement between the three evaluators in the ulnar notch angle at radiographic and tomographic exams. However, there was good/moderate agreement for articular incongruity measurement in the sagittal plane between evaluators. It was possible to conclude that none of the five radiographic incidences was better than the others for radiographic analysis because each incidence had a better identification of a particular elbow compartment; measurements at the tomographic exam to evaluate radioulnar incongruity had no reproductiveness in the frontal plane, but in sagittal plan had a good/moderate agreement between observers and the angle in ulnar notch presented no repeatability at radiographic exam and no reproductiveness at tomographic exam. (author)

  20. Tomographic findings of gastric gastrointestinal stromal tumor: a 14-case study

    International Nuclear Information System (INIS)

    Pelandre, Gustavo Lemos; Djahjah, Maria Celia; Nobre, Luiz Felipe; Gasparetto, Emerson Leandro; Marchiori, Edson; Pereira, Bruno Vilhena; Valadao, Marcus; Linhares, Eduardo

    2008-01-01

    Objective: The purpose of this study was to describe the tomographic findings of gastric gastrointestinal stromal tumor. Materials and methods: Fourteen patients with histopathologically and immunohistochemically confirmed gastric gastrointestinal stromal tumors, who had already been submitted to computed tomography scans before the treatment, were evaluated in the period between January 1999 and December 2006. The following tomographic variables were analyzed: lesion topography, size/dimensions, homogeneity, contour, margins, morphology, pattern and intravenous contrast-enhancement intensity, growth pattern, invasion of adjacent organs, presence of ulceration, fistula, calcifications, mesenteric fat infiltration, lymphadenomegaly and presence of distant metastasis. Results: Tumors were found in the body (57.1%) or in the gastric fundus (42.9%), with sizes ranging between 6.0 cm and 23.0 cm (mean, 11.5 cm). Predominantly extra luminal growth was observed in 57.1% of cases and intra/extra luminal in 35.7%. Subtle contrast-enhancement was observed in 50%, moderate in 50%, and heterogeneous in 64.3% of cases. Additionally, central hypodensity was observed in 64.3%, invasion of adjacent organs in 42.9%, and hepatic metastasis in 7.2% of cases. Conclusion: In the present study, the majority of tumors were found in the gastric body, with an average size of 11.5 cm, presenting with central hypodensity, heterogeneous contrast-enhancement and predominantly extraluminal growth. (author)

  1. Tomographic Environmental Sections for Environmental Mitigation Devices in Historical Centers

    Directory of Open Access Journals (Sweden)

    Roberta Cocci Grifoni

    2017-03-01

    Full Text Available Urban heat waves and the overall growing trend in the annual global temperature underline the importance of urban/architectural resilience and the need to reduce energy consumption. By designing urban voids, it is possible to create thermodynamic buffers, i.e., bubbles of controlled atmosphere that act as mediators between the natural and built environments, between the human body and the surrounding air, between meteorology and physiology (meteorological architecture. Multiple small actions in the urban fabric’s open spaces, such as replacing dark pavements or inserting vegetation and green spaces, are intended to improve outdoor comfort conditions and therefore the resilience of the city itself. This not only benefits the place’s quality, which is intrinsic to the new project, but also the insulating capacity of buildings, which are relieved of an external heat load. The design emphasis therefore changes from solid structures to the climate and weather conditions, which are invisible but perceivable. To design and control these constructed atmopheres, tomographic sections processed with computational fluid dynamics software (tomographic environmental section, TENS becomes necessary. It allows the effects of an extreme event on an outdoor environment to be evaluated in order to establish the appropriate (adaptive climate mitigation devices, especially in historical centers where energy retrofits are often discouraged. By fixing boundary conditions after a local intervention, the virtual environment can be simulated and then "sliced" to analyze initial values and verify the design improvements.

  2. Computed tomographic diagnosis of pulmonary nodules

    International Nuclear Information System (INIS)

    Onoue, Masataka

    1986-01-01

    One hundred and fifty-two pulmonary nodules (PNs) were examined by thin-section computed tomography (CT) and conventional tomography (tomography). In this study, 109 PNs were analyzed to assess tissue density by calculating the representative CT number (RCT no.) from a computer printout. For the primary malignancies, the mean RCT no. was 72 HU, with a standard deviation (SD) of 21 HU, and for metastases, it was 66 ± 19 HU. The RCT no. separating primary malignancy from benign lesions was 157 HU, the one including metastasis was 183 HU. In addition, dual-energy CT scan was performed to evaluate capability of diagnosing calcification in 35 PNs. Dual-energy CT scan had increased the reliability of CT diagnosis for PNs with RCT no. between 100 HU and 300 HU. The descriptive criteria of CT and tomography for 127 PNs were analyzed and statistical diagnoses by CT and tomography were compared with the results of their final diagnoses. CT and tomography had domonstrated similar sensitivities in the evaluation of primary malignancies; 86 % in CT and 90 % in tomography, and the same sensitivities (86 %) in diagnosing metastases. In evaluating benign PNs, CT was superior to tomography with capability to detect minimal calcification and fat density; the specificity was 80 % with CT, and 52 % with tomography (p < 0.025). Overall accuracy in the diagnosis for PNs was 82 % with CT, and 73 % with tomography, which was not different statistically. It can be concluded that CT is a reliable examination in the evaluation of PNs, and there is an advantage to the use of CT over tomography in diagnosing benign lesions. (author)

  3. Present state and development of positron tomographs

    International Nuclear Information System (INIS)

    Allemand, R.; Gariod, R.; Laval, M.; Tournier, F.

    1979-01-01

    This document presents the main characteristics of positron tomographs and analyses the relative importance of the parameters to be taken into consideration in the design of a tomograph: on the one hand, the physical parameters linked to the measurement of the annihilation photons by time coincidence and, on the other, the geometrical and technological parameters of prime importance in minimizing the many spurious effects. The last part endeavours to show this sort of instrumentation has evolved. Using the results obtained in our laboratory by mathematical simulation, the expected advantages are presented on the picture quality of the time of flight measurement of annihilation photons. Where the physical aspects of this method are concerned, the advantage of using cesium fluoride as scintillator is demonstrated [fr

  4. The bar coil for NMR tomograph

    International Nuclear Information System (INIS)

    Bogorodzki, P.; Piatkowski, A.; Wasielewski, J.

    1995-01-01

    The bar coil (bi-planar) for the NMR tomograph, designed for medical diagnostics, has been described. The tests of coil shown that it generates good homogenous magnetic field in a big volume what results in improving of the signal-to-noise ratio

  5. Tomographic Reconstruction from a Few Views: A Multi-Marginal Optimal Transport Approach

    Energy Technology Data Exchange (ETDEWEB)

    Abraham, I., E-mail: isabelle.abraham@cea.fr [CEA Ile de France (France); Abraham, R., E-mail: romain.abraham@univ-orleans.fr; Bergounioux, M., E-mail: maitine.bergounioux@univ-orleans.fr [Université d’Orléans, UFR Sciences, MAPMO, UMR 7349 (France); Carlier, G., E-mail: carlier@ceremade.dauphine.fr [CEREMADE, UMR CNRS 7534, Université Paris IX Dauphine, Pl. de Lattre de Tassigny (France)

    2017-02-15

    In this article, we focus on tomographic reconstruction. The problem is to determine the shape of the interior interface using a tomographic approach while very few X-ray radiographs are performed. We use a multi-marginal optimal transport approach. Preliminary numerical results are presented.

  6. Numerical evaluation of methods for computing tomographic projections

    International Nuclear Information System (INIS)

    Zhuang, W.; Gopal, S.S.; Hebert, T.J.

    1994-01-01

    Methods for computing forward/back projections of 2-D images can be viewed as numerical integration techniques. The accuracy of any ray-driven projection method can be improved by increasing the number of ray-paths that are traced per projection bin. The accuracy of pixel-driven projection methods can be increased by dividing each pixel into a number of smaller sub-pixels and projecting each sub-pixel. The authors compared four competing methods of computing forward/back projections: bilinear interpolation, ray-tracing, pixel-driven projection based upon sub-pixels, and pixel-driven projection based upon circular, rather than square, pixels. This latter method is equivalent to a fast, bi-nonlinear interpolation. These methods and the choice of the number of ray-paths per projection bin or the number of sub-pixels per pixel present a trade-off between computational speed and accuracy. To solve the problem of assessing backprojection accuracy, the analytical inverse Fourier transform of the ramp filtered forward projection of the Shepp and Logan head phantom is derived

  7. Computer-aided tomography (CT) in diagnosis of organic brain lesions in schizophrenics

    International Nuclear Information System (INIS)

    Vavilov, S.B.; Belova, O.G.; Nikiforchuk, N.M.; Savvateeva, N.Yu.; Atyasova, E.V.; Baev, A.A.

    1993-01-01

    The authors retrospectively analyse CT data obtained in examinations of 1745 patients divided into three groups. Group 1 consisted of 721 patients with schizophrenia, group consisted of 855 mentally normal subjects directed to computer tomographic examination with suspected organic involvement of the brain, and group 3 consisted of 169 mentally and neurologically normal subjects. Vascular diseases of the nervous system predominated in group 2 as against group 1, being 3.5 times more incident. No intracranial tumors were detected in controls; in schizophrenics computer tomographic signs of volumic brain lesions were detected in 1.5% of cases

  8. [Multispiral computed tomographic semiotics of laryngeal cancer].

    Science.gov (United States)

    Vasil'ev, P V; Iudin, A L; Sdvizhkov, A M; Kozhanov, L G

    2007-01-01

    Multispiral computed tomography (MSCT) with intravenous bolus contrasting is a currently available method for radiodiagnosis of laryngeal cancer. MSCT is of much higher informative value in estimating the extent of a tumorous lesion than the traditional radiodiagnostic techniques: linear tomography, lateral X-ray study, roentgenoscopy and roentgenography of the laryngopharynx and esophagus with barium meal.

  9. Experimental and theoretical analysis for improved microscope design of optical projection tomographic microscopy.

    Science.gov (United States)

    Coe, Ryan L; Seibel, Eric J

    2013-09-01

    We present theoretical and experimental results of axial displacement of objects relative to a fixed condenser focal plane (FP) in optical projection tomographic microscopy (OPTM). OPTM produces three-dimensional, reconstructed images of single cells from two-dimensional projections. The cell rotates in a microcapillary to acquire projections from different perspectives where the objective FP is scanned through the cell while the condenser FP remains fixed at the center of the microcapillary. This work uses a combination of experimental and theoretical methods to improve the OPTM instrument design.

  10. Tomographic ventricular reconstruction using multiple view first-pass radionuclide angiography

    International Nuclear Information System (INIS)

    Lacy, J.L.; Ball, M.E.; Verani, M.S.; Wiles, H.; Roberts, R.

    1985-01-01

    In first-pass radionuclide angiography (FPRA) images of both left and right ventricles are uncontaminated by adjacent structures. Thus, the problem of tomographic reconstruction is vastly simplified compared to equilibrium blood pool imaging in which all structures are imaged simultaneously. Tomographic reconstruction from a limited number of views may thus be possible. A simple filtered interpolative back-projection reconstruction technique was employed. In this technique interpolation was used between sectional distributions at successive angles. Interpolations yielding 9 and 13 back projection angles of 22.5 0 and 15 0 were evaluated. Ventricular borders were obtained in each back-projected tomographic slice by location of the intensity level which provided correct total ventricular volume. Cast cross sections were quantitatively well represented by these borders. This ventricular border definition algorithm forms the basis for applications of the technique in animals and humans

  11. Computed tomography in Alexander's disease

    Energy Technology Data Exchange (ETDEWEB)

    Holland, I M; Kendall, B E

    1980-10-01

    Two cases of biopsy-proven Alexander's disease are described with computed tomographic changes which, in our experience and on survey of the literature, have not occurred in any other condition. Such changes in a child with a progressive condition consistent with Alexander's disease, strongly support the diagnosis.

  12. Computed tomography of limy bile

    International Nuclear Information System (INIS)

    Yamamoto, Shinichiro; Kimoto, Masatoshi; Gunge, Nobuharu; Sano, Kaizo; Yamashita, Sachiko; Hirano, Yutaka

    1983-01-01

    The computed tomographic appearance of three cases of limy bile was reported. The CT findings consist of uniform high density within gallbladder, niveau formation between limy bile and noncalcified bile. Sagittal reconstruction of CT images was especially useful in the differentiation of limy bile and gallstones. (author)

  13. Tomographic anthropomorphic models. Pt. 4. Organ doses for adults due to idealized external photon exposures

    International Nuclear Information System (INIS)

    Zankl, M.; Petoussi-Henss, N.; Fill, U.; Regulla, D.

    2002-01-01

    The present report contains extensive tables and figures of conversion coefficients of organ and tissue equivalent dose, normalised to air kerma free in air for voxel anthropomorphic phantoms and for standard geometries of external photon radiation, estimated with Monte Carlo techniques. Four realistic adult voxel phantoms were used for the calculations, based on computed tomographic data of real people: three male phantoms, two of them being of average size, one representing a big man, and one female phantom of a tall and somewhat over weighted woman. (orig.)

  14. Tomographic anthropomorphic models. Pt. 4. Organ doses for adults due to idealized external photon exposures

    CERN Document Server

    Zankl, M; Petoussi-Henss, N; Regulla, D

    2002-01-01

    The present report contains extensive tables and figures of conversion coefficients of organ and tissue equivalent dose, normalised to air kerma free in air for voxel anthropomorphic phantoms and for standard geometries of external photon radiation, estimated with Monte Carlo techniques. Four realistic adult voxel phantoms were used for the calculations, based on computed tomographic data of real people: three male phantoms, two of them being of average size, one representing a big man, and one female phantom of a tall and somewhat over weighted woman.

  15. Tomographic image reconstruction using training images

    DEFF Research Database (Denmark)

    Soltani, Sara; Andersen, Martin Skovgaard; Hansen, Per Christian

    2017-01-01

    We describe and examine an algorithm for tomographic image reconstruction where prior knowledge about the solution is available in the form of training images. We first construct a non-negative dictionary based on prototype elements from the training images; this problem is formulated within...

  16. Image interface in Java for tomographic reconstruction in nuclear medicine

    International Nuclear Information System (INIS)

    Andrade, M.A.; Silva, A.M. Marques da

    2004-01-01

    The aim of this study is to implement a software for tomographic reconstruction of SPECT data from Nuclear Medicine with a flexible interface design, cross-platform, written in Java. Validation tests were performed based on SPECT simulated data. The results showed that the implemented algorithms and filters agree with the theoretical context. We intend to extend the system by implementing additional tomographic reconstruction techniques and Java threads, in order to provide simultaneously image processing. (author)

  17. Imaging of turbulent structures and tomographic reconstruction of TORPEX plasma emissivity

    International Nuclear Information System (INIS)

    Iraji, D.; Furno, I.; Fasoli, A.; Theiler, C.

    2010-01-01

    In the TORPEX [A. Fasoli et al., Phys. Plasmas 13, 055902 (2006)], a simple magnetized plasma device, low frequency electrostatic fluctuations associated with interchange waves, are routinely measured by means of extensive sets of Langmuir probes. To complement the electrostatic probe measurements of plasma turbulence and study of plasma structures smaller than the spatial resolution of probes array, a nonperturbative direct imaging system has been developed on TORPEX, including a fast framing Photron-APX-RS camera and an image intensifier unit. From the line-integrated camera images, we compute the poloidal emissivity profile of the plasma by applying a tomographic reconstruction technique using a pixel method and solving an overdetermined set of equations by singular value decomposition. This allows comparing statistical, spectral, and spatial properties of visible light radiation with electrostatic fluctuations. The shape and position of the time-averaged reconstructed plasma emissivity are observed to be similar to those of the ion saturation current profile. In the core plasma, excluding the electron cyclotron and upper hybrid resonant layers, the mean value of the plasma emissivity is observed to vary with (T e ) α (n e ) β , in which α=0.25-0.7 and β=0.8-1.4, in agreement with collisional radiative model. The tomographic reconstruction is applied to the fast camera movie acquired with 50 kframes/s rate and 2 μs of exposure time to obtain the temporal evolutions of the emissivity fluctuations. Conditional average sampling is also applied to visualize and measure sizes of structures associated with the interchange mode. The ω-time and the two-dimensional k-space Fourier analysis of the reconstructed emissivity fluctuations show the same interchange mode that is detected in the ω and k spectra of the ion saturation current fluctuations measured by probes. Small scale turbulent plasma structures can be detected and tracked in the reconstructed emissivity

  18. The electronics for the Donner 600-Crystal Positron Tomograph

    International Nuclear Information System (INIS)

    Cahoon, J.L.; Huesman, R.H.; Derenzo, S.E.; Geyer, A.B.; Uber, D.C.; Turko, B.T.; Budinger, T.F.

    1986-01-01

    The data acquisition system, designed for the Donner 600-Crystal Positron Tomograph, is described. Coincidence timing resolution of less than five nanoseconds full width at half maximum and data rates in excess of one million events per second are achieved by using high-speed emitter coupled logic circuits, first-in first-out memory to derandomize data flow, and parallel architecture to increase throughput. These data rates allow the acquisition of adequate transmission data in a reasonable amount of time. Good timing resolution minimizes accidental coincidences and permits data rates greater than 100,000 image-forming events per second for high-speed dynamic emission tomography. Additional scatter and accidental rejection are accomplished for transmission data by using an orbiting source and a look-up table for valid events. Calibration of this complex electronic system is performed automatically under computer control

  19. The Influence of the Size, Age and Sex on the Computed Tomographic Measured Size of the Pituitary Gland in Normal Horses.

    Science.gov (United States)

    Crijns, C P; Van Bree, H J; Broeckx, B J G; Schauvliege, S; Van Loon, G; Martens, A; Vanderperren, K; Dingemanse, W B; Gielen, I M

    2017-06-01

    The objective of this study was to examine the influence of the size, age and sex of the horse on the size of the pituitary gland and determine the possibility of using the pituitary gland height-to-brain area ratio (P:B ratio) to allow comparison of different sized and aged horses. Thirty-two horses without pituitary pars inter-media dysfunction that underwent a contrast-enhanced computed tomographic (CT) examination were included in a cross-sectional study. On the CT images, the pituitary gland height was measured and the P:B ratio was calculated. These measurements were correlated to the size, age and sex of the horses. The pituitary gland height was significantly associated with the size (P horses. No significant association was found between the P:B ratio and the size (P = 0.25), the age (P = 0.06) or the sex (P = 0.25) of the horses. In conclusion, the pituitary gland size varies between different sized and aged horses. The use of the P:B ratio is a valuable metric for making comparisons between the pituitary glands of these horses. © 2017 Blackwell Verlag GmbH.

  20. Cone Beam Computed Tomographic Analyses of the Position and Course of the Mandibular Canal: Relevance to the Sagittal Split Ramus Osteotomy

    Directory of Open Access Journals (Sweden)

    Ahmet Ercan Sekerci

    2014-01-01

    Full Text Available Purpose. The aim of this study was to document the position and course of the mandibular canal through the region of the mandibular angle and body in dental patients, using cone beam computed tomographic imaging. Methods. The position and course of the mandibular canal from the region of the third molar to the first molar were measured at five specific locations in the same plane: at three different positions just between the first and second molars; between the second and third molars; and just distal to the third molar. Results. The study sample was composed of 500 hemimandibles from 250 dental patients with a mean age of 26.32. Significant differences were found between genders, distances, and positions. B decreased significantly from the anterior positions to the posterior positions in both females and males. The mean values of S and CB increased significantly from the posterior positions to the anterior positions in both females and males. Conclusion. Because the sagittal split ramus osteotomy is a technically difficult procedure, we hope that the findings of the present study will help the surgeon in choosing the safest surgical technique for the treatment of mandibular deformities.

  1. Potentialities of computed tomography and ultrasonography in colonic cancer

    International Nuclear Information System (INIS)

    Gorshkov, A.N.

    2001-01-01

    Data of examination of 59 patients with colonic cancer were used to consider the potentialities of transabdominal, transrectal ultrasonography and X-ay compound tomography and to assess their value in diagnosing colonic cancer, including its minor forms. Ultrasound and computed tomographic semiotics of colonic cancer and determines a place of the above techniques in the algorithm of radiation and instrumental studies are described. Inclusion of these techniques into the diagnostic algorithm may solve a range of differentially diagnostic problems and allows a preliminary analysis to be made in a tumor lesion according to the International TNM classification. Ultrasonography and X-ray computed tomography should be included into a range of basic methods for diagnosis of colonic cancer [ru

  2. Incremental prognostic value of coronary computed tomographic angiography high-risk plaque characteristics in newly symptomatic patients.

    Science.gov (United States)

    Fujimoto, Shinichiro; Kondo, Takeshi; Takamura, Kazuhisa; Baber, Usman; Shinozaki, Tomohiro; Nishizaki, Yuji; Kawaguchi, Yuko; Matsumori, Rie; Hiki, Makoto; Miyauchi, Katsumi; Daida, Hiroyuki; Hecht, Harvey; Stone, Gregg W; Narula, Jagat

    2016-06-01

    The incremental prognostic value of the plaque features in coronary computed tomographic angiography (CTA) has not been well assessed. This study was designed to determine whether CTA high-risk plaques have prognostic value incremental to the Framingham risk score (FRS) and the severity of luminal obstruction. A total of 628 newly symptomatic patients without known coronary artery disease underwent CTA. They were followed for a median of 677 days during which there were 26 cardiac events, including cardiac death, acute myocardial infarction, and hospitalization for unstable angina. Incremental prognostic value of adding plaque characteristics to the number of diseased vessels and the FRS was evaluated using 3 Cox models and net reclassification indexes. The discrimination index was significantly increased by adding the number of diseased vessels to the FRS (change in c-statistic from 65.8% to 78.6%, p=0.028) but not significantly by further adding plaque characteristics (change in c-statistic from 78.6% to 80.0%, p=0.812). However, improved model-fitting by adding plaque characteristics into the linear combination with risk score and the number of diseased vessels (p=0.007 from likelihood ratio test) and the lowest value of Akaike's information criteria of that model indicated that plaque characteristics improved both predictive accuracy and discrimination perspective. More subjects reclassified by plaque characteristics were moved to directions consistent with their subsequent cardiac event status than in an inconsistent direction. Evaluation of CTA plaque characteristics may provide incremental prognostic value to the number of diseased vessels and the FRS. Copyright © 2015 Japanese College of Cardiology. Published by Elsevier Ltd. All rights reserved.

  3. Pressure spectra from single-snapshot tomographic PIV

    Science.gov (United States)

    Schneiders, Jan F. G.; Avallone, Francesco; Pröbsting, Stefan; Ragni, Daniele; Scarano, Fulvio

    2018-03-01

    The power spectral density and coherence of temporal pressure fluctuations are obtained from low-repetition-rate tomographic PIV measurements. This is achieved by extension of recent single-snapshot pressure evaluation techniques based upon the Taylor's hypothesis (TH) of frozen turbulence and vortex-in-cell (VIC) simulation. Finite time marching of the measured instantaneous velocity fields is performed using TH and VIC. Pressure is calculated from the resulting velocity time series. Because of the theoretical limitations, the finite time marching can be performed until the measured flow structures are convected out of the measurement volume. This provides a lower limit of resolvable frequency range. An upper limit is given by the spatial resolution of the measurements. Finite time-marching approaches are applied to low-repetition-rate tomographic PIV data of the flow past a straight trailing edge at 10 m/s. Reference results of the power spectral density and coherence are obtained from surface pressure transducers. In addition, the results are compared to state-of-the-art experimental data obtained from time-resolved tomographic PIV performed at 10 kHz. The time-resolved approach suffers from low spatial resolution and limited maximum acquisition frequency because of hardware limitations. Additionally, these approaches strongly depend upon the time kernel length chosen for pressure evaluation. On the other hand, the finite time-marching approaches make use of low-repetition-rate tomographic PIV measurements that offer higher spatial resolution. Consequently, increased accuracy of the power spectral density and coherence of pressure fluctuations are obtained in the high-frequency range, in comparison to the time-resolved measurements. The approaches based on TH and VIC are found to perform similarly in the high-frequency range. At lower frequencies, TH is found to underestimate coherence and intensity of the pressure fluctuations in comparison to time-resolved PIV

  4. Computer tomographic demonstration of the popliteal artery entrapment syndrome

    International Nuclear Information System (INIS)

    Alder, W.; Zwicker, H.

    1979-01-01

    The popliteal artery entrapment syndrome can be diagnosed by computer tomography with a greater degree of certainty than by angiography. The advantage of computer tomography depends on the simultaneous demonstration of the position of the vessel and of the surrounding muscles and their abnormal situation. (orig.) [de

  5. Computed tomographic findings in penetrating peptic ulcer

    International Nuclear Information System (INIS)

    Madrazo, B.L.; Halpert, R.D.; Sandler, M.A.; Pearlberg, J.L.

    1984-01-01

    Four cases of peptic ulcer penetrating the head of the pancreas were diagnosed by computed tomography (CT). Findings common to 3 cases included (a) an ulcer crater, (b) a sinus tract, and (c) enlargement of the head of the pancreas. Unlike other modalities, the inherent spatial resolution of CT allows a convenient diagnosis of this important complication of peptic ulcer disease

  6. Influence of laser power on atom probe tomographic analysis of boron distribution in silicon

    Energy Technology Data Exchange (ETDEWEB)

    Tu, Y., E-mail: ytu@imr.tohoku.ac.jp [The Oarai Center, Institute for Materials Research, Tohoku University, Oarai, Ibaraki 311-1313 (Japan); Takamizawa, H.; Han, B.; Shimizu, Y.; Inoue, K.; Toyama, T. [The Oarai Center, Institute for Materials Research, Tohoku University, Oarai, Ibaraki 311-1313 (Japan); Yano, F. [The Oarai Center, Institute for Materials Research, Tohoku University, Oarai, Ibaraki 311-1313 (Japan); Tokyo City University, Setagaya, Tokyo 158-8557 (Japan); Nishida, A. [Renesas Electronics Corporation, Hitachinaka, Ibaraki 312-8504 (Japan); Nagai, Y. [The Oarai Center, Institute for Materials Research, Tohoku University, Oarai, Ibaraki 311-1313 (Japan)

    2017-02-15

    The relationship between the laser power and the three-dimensional distribution of boron (B) in silicon (Si) measured by laser-assisted atom probe tomography (APT) is investigated. The ultraviolet laser employed in this study has a fixed wavelength of 355 nm. The measured distributions are almost uniform and homogeneous when using low laser power, while clear B accumulation at the low-index pole of single-crystalline Si and segregation along the grain boundaries in polycrystalline Si are observed when using high laser power (100 pJ). These effects are thought to be caused by the surface migration of atoms, which is promoted by high laser power. Therefore, for ensuring a high-fidelity APT measurement of the B distribution in Si, high laser power is not recommended. - Highlights: • Influence of laser power on atom probe tomographic analysis of B distribution in Si is investigated. • When using high laser power, inhomogeneous distributions of B in single-crystalline and polycrystalline Si are observed. • Laser promoted migration of B atoms over the specimen is proposed to explain these effects.

  7. New method to analyze internal disruptions with tomographic reconstructions

    Energy Technology Data Exchange (ETDEWEB)

    Tanzi, C.P. [EURATOM-FOM Association, FOM-Instituut voor Plasmafysica Rijnhuizen, P.O. BOX 1207, 3430 BE Nieuwegein (The Netherlands); de Blank, H.J. [Max-Planck-Institut fuer Plasmaphysik, EURATOM-IPP Association, 85740 Garching (Germany)

    1997-03-01

    Sawtooth crashes have been investigated on the Rijnhuizen Tokamak Project (RTP) [N. J. Lopes Cardozo {ital et al.}, {ital Proceedings of the 14th International Conference on Plasma Physics and Controlled Nuclear Fusion Research}, W{umlt u}rzburg, 1992 (International Atomic Energy Agency, Vienna, 1993), Vol. 1, p. 271]. Internal disruptions in tokamak plasmas often exhibit an m=1 poloidal mode structure prior to the collapse which can be clearly identified by means of multicamera soft x-ray diagnostics. In this paper tomographic reconstructions of such m=1 modes are analyzed with a new method, based on magnetohydrodynamic (MHD) invariants computed from the two-dimensional emissivity profiles, which quantifies the amount of profile flattening not only after the crash but also during the precursor oscillations. The results are interpreted by comparing them with two models which simulate the measurements of the m=1 redistribution of soft x-ray emissivity prior to the sawtooth crash. One model is based on the magnetic reconnection model of Kadomtsev. The other involves ideal MHD motion only. In cases where differences in magnetic topology between the two models cannot be seen in the tomograms, the analysis of profile flattening has an advantage. The analysis shows that in RTP the clearly observed m=1 displacement of some sawteeth requires the presence of convective ideal MHD motion, whereas other precursors are consistent with magnetic reconnection of up to 75{percent} of the magnetic flux within the q=1 surface. The possibility of ideal interchange combined with enhanced cross-field transport is not excluded. {copyright} {ital 1997 American Institute of Physics.}

  8. New method to analyze internal disruptions with tomographic reconstructions

    International Nuclear Information System (INIS)

    Tanzi, C.P.; de Blank, H.J.

    1997-01-01

    Sawtooth crashes have been investigated on the Rijnhuizen Tokamak Project (RTP) [N. J. Lopes Cardozo et al., Proceedings of the 14th International Conference on Plasma Physics and Controlled Nuclear Fusion Research, Wuerzburg, 1992 (International Atomic Energy Agency, Vienna, 1993), Vol. 1, p. 271]. Internal disruptions in tokamak plasmas often exhibit an m=1 poloidal mode structure prior to the collapse which can be clearly identified by means of multicamera soft x-ray diagnostics. In this paper tomographic reconstructions of such m=1 modes are analyzed with a new method, based on magnetohydrodynamic (MHD) invariants computed from the two-dimensional emissivity profiles, which quantifies the amount of profile flattening not only after the crash but also during the precursor oscillations. The results are interpreted by comparing them with two models which simulate the measurements of the m=1 redistribution of soft x-ray emissivity prior to the sawtooth crash. One model is based on the magnetic reconnection model of Kadomtsev. The other involves ideal MHD motion only. In cases where differences in magnetic topology between the two models cannot be seen in the tomograms, the analysis of profile flattening has an advantage. The analysis shows that in RTP the clearly observed m=1 displacement of some sawteeth requires the presence of convective ideal MHD motion, whereas other precursors are consistent with magnetic reconnection of up to 75% of the magnetic flux within the q=1 surface. The possibility of ideal interchange combined with enhanced cross-field transport is not excluded. copyright 1997 American Institute of Physics

  9. Decomposition of time-resolved tomographic PIV

    NARCIS (Netherlands)

    Schmid, P.J.; Violato, D.; Scarano, F.

    2012-01-01

    An experimental study has been conducted on a transitional water jet at a Reynolds number of Re = 5,000. Flow fields have been obtained by means of time-resolved tomographic particle image velocimetry capturing all relevant spatial and temporal scales. The measured threedimensional flow fields have

  10. Connections model for tomographic images reconstruction

    International Nuclear Information System (INIS)

    Rodrigues, R.G.S.; Pela, C.A.; Roque, S.F. A.C.

    1998-01-01

    This paper shows an artificial neural network with an adequately topology for tomographic image reconstruction. The associated error function is derived and the learning algorithm is make. The simulated results are presented and demonstrate the existence of a generalized solution for nets with linear activation function. (Author)

  11. Matching tomographic IMRT fields with static photon fields

    International Nuclear Information System (INIS)

    Sethi, A.; Leybovich, L.; Dogan, N.; Emami, B.

    2001-01-01

    The matching of abutting radiation fields presents a challenging problem in radiation therapy. Due to sharp penumbra of linear accelerator beams, small (1-2 mm) errors in field positioning can lead to large (>30%) hot or cold spots in the abutment region. With head and neck immobilization devices (thermoplastic mask/aquaplast) an average setup error of 3 mm has been reported. Therefore hot or cold spots approaching 50% of the prescription dose may occur along the matchline. Although abutting radiation fields have been investigated for static fields, there is no reported study regarding matching of tomographic IMRT and static fields. Compared to static fields, the matching of tomographic IMRT fields with static fields is more complicated. Since IMRT and static fields are planned on separate treatment planning computers, the dose in the abutment region is not specified. In addition, commonly used techniques for matching fields, such as feathering of junctions, are not practical. We have developed a method that substantially reduces dose inhomogeneity in the abutment region. In this method, a 'buffer zone' around the matchline was created and was included as part of the target for both IMRT and static field plans. In both fields, a small dose gradient (≤3%/mm) in the buffer zone was created. In the IMRT plan, the buffer zone was divided into three sections with dose varying from 83% to 25% of prescription dose. The static field dose profile was modified using either a specially designed physical (hard) or a dynamic (soft) wedge. When these modified fields were matched, the combined dose in the abutment region varied by ≤10% in the presence of setup errors spanning 4 mm (±2 mm) when the hard wedge was used and 10 mm (±5 mm) with the soft wedge

  12. HFSB-seeding for large-scale tomographic PIV in wind tunnels

    Science.gov (United States)

    Caridi, Giuseppe Carlo Alp; Ragni, Daniele; Sciacchitano, Andrea; Scarano, Fulvio

    2016-12-01

    A new system for large-scale tomographic particle image velocimetry in low-speed wind tunnels is presented. The system relies upon the use of sub-millimetre helium-filled soap bubbles as flow tracers, which scatter light with intensity several orders of magnitude higher than micron-sized droplets. With respect to a single bubble generator, the system increases the rate of bubbles emission by means of transient accumulation and rapid release. The governing parameters of the system are identified and discussed, namely the bubbles production rate, the accumulation and release times, the size of the bubble injector and its location with respect to the wind tunnel contraction. The relations between the above parameters, the resulting spatial concentration of tracers and measurement of dynamic spatial range are obtained and discussed. Large-scale experiments are carried out in a large low-speed wind tunnel with 2.85 × 2.85 m2 test section, where a vertical axis wind turbine of 1 m diameter is operated. Time-resolved tomographic PIV measurements are taken over a measurement volume of 40 × 20 × 15 cm3, allowing the quantitative analysis of the tip-vortex structure and dynamical evolution.

  13. Mesooptical microscope as a tomographical device

    International Nuclear Information System (INIS)

    Soroko, L.M.

    1989-01-01

    It is shown that there are at least four regions which are common for the mesooptical microscopes, on the one hand, and for the reconstructed tomography, on the other hand. The following characteristics of the mesooptical microscope show the tomographical properties: the structure of the output data concerning the orientation and the position in space of the straight-line objects going at small angles with the perpendicular to the given tomographic plane, the behaviour of the two-dimensional fourier-transform of the straight-line object in the course of the rotation of this object with respect to the specified axis in space, the scanning algorithm of the nuclear emulsion volume by the fence-like illuminated region in the mesooptical microscope for searching for particle tracks going parallel to the optical axis of the microscope, and, finally, the fact that the mesooptical images of the straight-line particle tracks with a common vertex in the nuclear emulsion lie on the sinogram. 12 refs.; 16 figs

  14. Computerized tomographic in non-destructive testing

    International Nuclear Information System (INIS)

    Lopes, R.T.

    1988-01-01

    The process of computerized tomography has been developed for medical imaging purposes using tomographs with X-ray, and little attention has been given to others possibles applications of technique, because of its cost. As an alternative for the problem, we constructed a Tomographic System (STAC-1), using gamma-rays, for nonmedical applications. In this work we summarize the basic theory of reconstructing images using computerized tomography and we describe the considerations leading to the development of the experimental system. The method of reconstruction image implanted in the system is the filtered backprojection or convolution, with a digital filters system to carried on a pre-filtering in the projections. The experimental system is described, with details of control and the data processing. An alternative and a complementary system, using film as a detector is shown in preliminary form . This thesis discuss and shows the theorical and practical aspects, considered in the construction of the STAC-1, and also its limitations and apllications [pt

  15. Tomographic scanning apparatus

    International Nuclear Information System (INIS)

    Abele, M.

    1983-01-01

    A computerized tomographic scanning apparatus suitable for diagnosis and for improving target identification in stereotactic neurosurgery is described. It consists of a base, a source of penetrating energy, a detector which produces scanning signals and detector positioning means. A frame with top and bottom arms secures the detector and source to the top and bottom arms respectively. A drive mechanism rotates the frame about an axis along which the frame may also be moved. Finally, the detector may be moved relative to the bottom arm in a direction contrary to the rotation of the frame. (U.K.)

  16. Misty mesentery: computed tomography findings

    International Nuclear Information System (INIS)

    Ahualli, Jorge; Mendez Uriburu, Luis; Ravera, Maria L.; Cikman, Pablo

    2008-01-01

    An alteration in the density of the mesenteric adipose tissue is often the principal clue of underlying mesenteric and bowel disease. The term 'Misty Mesentery' describes the computed tomographic appearance of mesenteric fat infiltrated by inflammatory cells, fluid (edema, lymph, and/or blood), tumor, and fibrosis. (author) [es

  17. Four-dimensional computed tomographic analysis of esophageal mobility during normal respiration

    International Nuclear Information System (INIS)

    Dieleman, Edith; Senan, Suresh; Vincent, Andrew; Lagerwaard, Frank J.; Slotman, Ben J.; Soernsen de Koste, John R. van

    2007-01-01

    Background: Chemo-radiotherapy for thoracic tumors can result in high-grade radiation esophagitis. Treatment planning to reduce esophageal irradiation requires organ motion to be accounted for. In this study, esophageal mobility was assessed using four-dimensional computed tomography (4DCT). Methods and Materials: Thoracic 4DCT scans were acquired on a 16-slice CT scanner in 29 patients. The outer esophageal wall was contoured in two extreme phases of respiration in 9 patients with nonesophageal malignancies. The displacement of the center of contour was measured at 2-cm intervals. In 20 additional patients with Stage I lung cancer, the esophagus was contoured in all 10 phases of each 4DCT at five defined anatomic levels. Both approaches were then applied to 4DCT scans of 4 patients who each had two repeat scans performed. A linear mixed effects model was constructed with fixed effects: measurement direction, measurement type, and measurement location along the cranio-caudal axis. Results: Measurement location and direction were significant descriptive parameters (Wald F-tests, p < 0.001), and the interaction term between the two was significant (p = 0.02). Medio-lateral mobility exceeded dorso-ventral mobility in the lower half of the esophagus but was of a similar magnitude in the upper half. Margins that would have incorporated all movement in medio-lateral and dorso-ventral directions were 5 mm proximally, 7 mm and 6 mm respectively in the mid-esophagus, and 9 mm and 8 mm respectively in the distal esophagus. Conclusions: The distal esophagus shows more mobility. Margins for mobility that can encompass all movement were derived for use in treatment planning, particularly for stereotactic radiotherapy

  18. Rapid estimation of split renal function in kidney donors using software developed for computed tomographic renal volumetry

    Energy Technology Data Exchange (ETDEWEB)

    Kato, Fumi, E-mail: fumikato@med.hokudai.ac.jp [Department of Radiology, Hokkaido University Graduate School of Medicine, N15, W7, Kita-ku, Sapporo, Hokkaido 060-8638 (Japan); Kamishima, Tamotsu, E-mail: ktamotamo2@yahoo.co.jp [Department of Radiology, Hokkaido University Graduate School of Medicine, N15, W7, Kita-ku, Sapporo, Hokkaido 060-8638 (Japan); Morita, Ken, E-mail: kenordic@carrot.ocn.ne.jp [Department of Urology, Hokkaido University Graduate School of Medicine, N15, W7, Kita-ku, Sapporo, 060-8638 (Japan); Muto, Natalia S., E-mail: nataliamuto@gmail.com [Department of Radiology, Hokkaido University Graduate School of Medicine, N15, W7, Kita-ku, Sapporo, Hokkaido 060-8638 (Japan); Okamoto, Syozou, E-mail: shozo@med.hokudai.ac.jp [Department of Nuclear Medicine, Hokkaido University Graduate School of Medicine, N15, W7, Kita-ku, Sapporo, 060-8638 (Japan); Omatsu, Tokuhiko, E-mail: omatoku@nirs.go.jp [Department of Radiology, Hokkaido University Graduate School of Medicine, N15, W7, Kita-ku, Sapporo, Hokkaido 060-8638 (Japan); Oyama, Noriko, E-mail: ZAT04404@nifty.ne.jp [Department of Radiology, Hokkaido University Graduate School of Medicine, N15, W7, Kita-ku, Sapporo, Hokkaido 060-8638 (Japan); Terae, Satoshi, E-mail: saterae@med.hokudai.ac.jp [Department of Radiology, Hokkaido University Graduate School of Medicine, N15, W7, Kita-ku, Sapporo, Hokkaido 060-8638 (Japan); Kanegae, Kakuko, E-mail: IZW00143@nifty.ne.jp [Department of Nuclear Medicine, Hokkaido University Graduate School of Medicine, N15, W7, Kita-ku, Sapporo, 060-8638 (Japan); Nonomura, Katsuya, E-mail: k-nonno@med.hokudai.ac.jp [Department of Urology, Hokkaido University Graduate School of Medicine, N15, W7, Kita-ku, Sapporo, 060-8638 (Japan); Shirato, Hiroki, E-mail: shirato@med.hokudai.ac.jp [Department of Radiology, Hokkaido University Graduate School of Medicine, N15, W7, Kita-ku, Sapporo, Hokkaido 060-8638 (Japan)

    2011-07-15

    Purpose: To evaluate the speed and precision of split renal volume (SRV) measurement, which is the ratio of unilateral renal volume to bilateral renal volume, using a newly developed software for computed tomographic (CT) volumetry and to investigate the usefulness of SRV for the estimation of split renal function (SRF) in kidney donors. Method: Both dynamic CT and renal scintigraphy in 28 adult potential living renal donors were the subjects of this study. We calculated SRV using the newly developed volumetric software built into a PACS viewer (n-SRV), and compared it with SRV calculated using a conventional workstation, ZIOSOFT (z-SRV). The correlation with split renal function (SRF) using {sup 99m}Tc-DMSA scintigraphy was also investigated. Results: The time required for volumetry of bilateral kidneys with the newly developed software (16.7 {+-} 3.9 s) was significantly shorter than that of the workstation (102.6 {+-} 38.9 s, p < 0.0001). The results of n-SRV (49.7 {+-} 4.0%) were highly consistent with those of z-SRV (49.9 {+-} 3.6%), with a mean discrepancy of 0.12 {+-} 0.84%. The SRF also agreed well with the n-SRV, with a mean discrepancy of 0.25 {+-} 1.65%. The dominant side determined by SRF and n-SRV showed agreement in 26 of 28 cases (92.9%). Conclusion: The newly developed software for CT volumetry was more rapid than the conventional workstation volumetry and just as accurate, and was suggested to be useful for the estimation of SRF and thus the dominant side in kidney donors.

  19. Central tarsal bone fractures in horses not used for racing: Computed tomographic configuration and long-term outcome of lag screw fixation.

    Science.gov (United States)

    Gunst, S; Del Chicca, F; Fürst, A E; Kuemmerle, J M

    2016-09-01

    There are no reports on the configuration of equine central tarsal bone fractures based on cross-sectional imaging and clinical and radiographic long-term outcome after internal fixation. To report clinical, radiographic and computed tomographic findings of equine central tarsal bone fractures and to evaluate the long-term outcome of internal fixation. Retrospective case series. All horses diagnosed with a central tarsal bone fracture at our institution in 2009-2013 were included. Computed tomography and internal fixation using lag screw technique was performed in all patients. Medical records and diagnostic images were reviewed retrospectively. A clinical and radiographic follow-up examination was performed at least 1 year post operatively. A central tarsal bone fracture was diagnosed in 6 horses. Five were Warmbloods used for showjumping and one was a Quarter Horse used for reining. All horses had sagittal slab fractures that began dorsally, ran in a plantar or plantaromedial direction and exited the plantar cortex at the plantar or plantaromedial indentation of the central tarsal bone. Marked sclerosis of the central tarsal bone was diagnosed in all patients. At long-term follow-up, 5/6 horses were sound and used as intended although mild osteophyte formation at the distal intertarsal joint was commonly observed. Central tarsal bone fractures in nonracehorses had a distinct configuration but radiographically subtle additional fracture lines can occur. A chronic stress related aetiology seems likely. Internal fixation of these fractures based on an accurate diagnosis of the individual fracture configuration resulted in a very good prognosis. © 2015 EVJ Ltd.

  20. The Basilar Artery on Computed Tomography Angiography Prognostic Score for Basilar Artery Occlusion.

    Science.gov (United States)

    Alemseged, Fana; Shah, Darshan G; Diomedi, Marina; Sallustio, Fabrizio; Bivard, Andrew; Sharma, Gagan; Mitchell, Peter J; Dowling, Richard J; Bush, Steven; Yan, Bernard; Caltagirone, Carlo; Floris, Roberto; Parsons, Mark W; Levi, Christopher R; Davis, Stephen M; Campbell, Bruce C V

    2017-03-01

    Basilar artery occlusion is associated with high risk of disability and mortality. This study aimed to assess the prognostic value of a new radiological score: the Basilar Artery on Computed Tomography Angiography (BATMAN) score. A retrospective analysis of consecutive stroke patients with basilar artery occlusion diagnosed on computed tomographic angiography was performed. BATMAN score is a 10-point computed tomographic angiography-based grading system which incorporates thrombus burden and the presence of collaterals. Reliability was assessed with intraclass coefficient correlation. Good outcome was defined as modified Rankin Scale score of ≤3 at 3 months and successful reperfusion as thrombolysis in cerebral infarction 2b-3. BATMAN score was externally validated and compared with the Posterior Circulation Collateral score. The derivation cohort included 83 patients with 41 in the validation cohort. In receiver operating characteristic (ROC) analysis, BATMAN score had an area under receiver operating characteristic curve of 0.81 (95% confidence interval [CI], 0.7-0.9) in derivation cohort and an area under receiver operating characteristic curve of 0.74 (95% CI, 0.6-0.9) in validation cohort. In logistic regression adjusted for age and clinical severity, BATMAN score of BATMAN score of BATMAN score had greater accuracy compared with Posterior Circulation Collateral score ( P =0.04). The addition of collateral quality to clot burden in BATMAN score seems to improve prognostic accuracy in basilar artery occlusion patients. © 2017 American Heart Association, Inc.

  1. Comparison of the Multidetector-row Computed Tomographic Angiography Axial and Coronal Planes' Usefulness for Detecting Thoracodorsal Artery Perforators

    Science.gov (United States)

    Kim, Jong Gyu

    2012-01-01

    Background During the planning of a thoracodorsal artery perforator (TDAP) free flap, preoperative multidetector-row computed tomographic (MDCT) angiography is valuable for predicting the locations of perforators. However, CT-based perforator mapping of the thoracodorsal artery is not easy because of its small diameter. Thus, we evaluated 1-mm-thick MDCT images in multiple planes to search for reliable perforators accurately. Methods Between July 2010 and October 2011, 19 consecutive patients (13 males, 6 females) who underwent MDCT prior to TDAP free flap operations were enrolled in this study. Patients ranged in age from 10 to 75 years (mean, 39.3 years). MDCT images were acquired at a thickness of 1 mm in the axial, coronal, and sagittal planes. Results The thoracodorsal artery perforators were detected in all 19 cases. The reliable perforators originating from the descending branch were found in 14 cases, of which 6 had transverse branches. The former were well identified in the coronal view, and the latter in the axial view. The location of the most reliable perforators on MDCT images corresponded well with the surgical findings. Conclusions Though MDCT has been widely used in performing the abdominal perforator free flap for detecting reliable perforating vessels, it is not popular in the TDAP free flap. The results of this study suggest that multiple planes of MDCT may increase the probability of detecting the most reliable perforators, along with decreasing the probability of missing available vessels. PMID:22872839

  2. Three dimensional reconstruction of computed tomographic images by computer graphics method

    International Nuclear Information System (INIS)

    Kashiwagi, Toru; Kimura, Kazufumi.

    1986-01-01

    A three dimensional computer reconstruction system for CT images has been developed in a commonly used radionuclide data processing system using a computer graphics technique. The three dimensional model was constructed from organ surface information of CT images (slice thickness: 5 or 10 mm). Surface contours of the organs were extracted manually from a set of parallel transverse CT slices in serial order and stored in the computer memory. Interpolation was made between a set of the extracted contours by cubic spline functions, then three dimensional models were reconstructed. The three dimensional images were displayed as a wire-frame and/or solid models on the color CRT. Solid model images were obtained as follows. The organ surface constructed from contours was divided into many triangular patches. The intensity of light to each patch was calculated from the direction of incident light, eye position and the normal to the triangular patch. Firstly, this system was applied to the liver phantom. Reconstructed images of the liver phantom were coincident with the actual object. This system also has been applied to human various organs such as brain, lung, liver, etc. The anatomical organ surface was realistically viewed from any direction. The images made us more easily understand the location and configuration of organs in vivo than original CT images. Furthermore, spacial relationship among organs and/or lesions was clearly obtained by superimposition of wire-frame and/or different colored solid models. Therefore, it is expected that this system is clinically useful for evaluating the patho-morphological changes in broad perspective. (author)

  3. Tomographic imaging of subducted lithosphere below northwest Pacific island arcs

    Science.gov (United States)

    Van Der Hilst, R.; Engdahl, R.; Spakman, W.; Nolet, G.

    1991-01-01

    The seismic tomography problem does not have a unique solution, and published tomographic images have been equivocal with regard to the deep structure of subducting slabs. An improved tomographic method, using a more realistic background Earth model and surf ace-reflected as well as direct seismic phases, shows that slabs beneath the Japan and Izu Bonin island arcs are deflected at the boundary between upper and lower mantle, whereas those beneath the northern Kuril and Mariana arcs sink into the lower mantle.

  4. The early development of medial coronoid disease in growing Labrador retrivers: Radographic, computed tomographic, necropsy and micro-computed tomographic findings

    NARCIS (Netherlands)

    Lau, S.F.; Wolschrijn, C.F.; Hazewinkel, H.A.W.; Siebelt, M; Voorhout, G.

    2013-01-01

    Abstract Medial coronoid disease (MCD) encompasses lesions of the entire medial coronoid process (MCP), both of the articular cartilage and the subchondral bone. To detect the earliest signs of MCD, radiography and computed tomography were used to monitor the development of MCD in 14 Labrador

  5. COMPUTED TOMOGRAPHIC EVALUATION OF CANINE PHARYNGEAL NEOPLASIA

    OpenAIRE

    Carozzi, Gregorio

    2016-01-01

    Computed tomography (CT) is commonly used to investigate head tumours in dogs, and is a fundamental part of the diagnostic work-up, for diagnosis, staging and planning therapy in neoplastic disease. Nasal diseases, either neoplastic or non-neoplastic diseases, oral neoplasia, brain disease, thyroid or carotid body neoplasia have been extensively studied. However little information are available for lesions of the pharyngeal area. In this thesis, cases of dogs affected by pharyngeal neoplas...

  6. Evaluation of tomographic ISOCAM Park II gamma camera parameters using Monte Carlo method

    International Nuclear Information System (INIS)

    Oramas Polo, Ivón

    2015-01-01

    In this paper the evaluation of tomographic ISOCAM Park II gamma camera parameters was performed using the Monte Carlo code SIMIND. The parameters uniformity, resolution and contrast were evaluated by Jaszczak phantom simulation. In addition the qualitative assessment of the center of rotation was performed. The results of the simulation are compared and evaluated against the specifications of the manufacturer of the gamma camera and taking into account the National Protocol for Quality Control of Nuclear Medicine Instruments of the Cuban Medical Equipment Control Center. A computational Jaszczak phantom model with three different distributions of activity was obtained. They can be used to perform studies with gamma cameras. (author)

  7. Remote diagnosis via a telecommunication satellite--ultrasonic tomographic image transmission experiments.

    Science.gov (United States)

    Nakajima, I; Inokuchi, S; Tajima, T; Takahashi, T

    1985-04-01

    An experiment to transmit ultrasonic tomographic section images required for remote medical diagnosis and care was conducted using the mobile telecommunication satellite OSCAR-10. The images received showed the intestinal condition of a patient incapable of verbal communication, however the image screen had a fairly coarse particle structure. On the basis of these experiments, were considered as the transmission of ultrasonic tomographic images extremely effective in remote diagnosis.

  8. Dose determination in computed tomography; Determinacion de dosis en tomografia computada

    Energy Technology Data Exchange (ETDEWEB)

    Descamps, C.; Garrigo, E.; Venencia, D. [Fundacion Marie Curie, Instituto Privado de Radioterapia, Departamento de Fisica Medica, Obispo Oro 423, X5000BFI Cordoba (Argentina); Gonzalez, M. [Universidad Nacional de Cordoba, Facultad de Ciencias Exactas, Fisicas y Naturales, Av. Velez Sarsfield 299, Corboba (Argentina); Germanier, A., E-mail: agermani@ceprocor.uncor.edu [Ministerio de Ciencia y Tecnologia, Ceprocor, Alvarez de Arenas 230, X5004AAP Barrio Juniors, Cordoba (Argentina)

    2011-10-15

    In the last years the methodologies to determine the dose in computed tomography have been revised. In this work was realized a dosimetric study about the exploration protocols used for simulation of radiotherapy treatments. The methodology described in the Report No. 111 of the American Association of Medical Physiques on a computed tomograph of two cuts was applied. A cylindrical phantom of water was used with dimensions: 30 cm of diameter and 50 cm of longitude that simulates the absorption and dispersion conditions of a mature body of size average. The doses were determined with ionization chamber and thermoluminescent dosimetry. The results indicate that the dose information that provides the tomograph underestimates the dose between 32 and 35%.

  9. Computed tomographical evaluation of diabetic nephropathy

    International Nuclear Information System (INIS)

    Ubara, Yoshifumi; Hara, Shigeko; Arizono, Kenji; Katori, Hideyuki; Yamada, Akira; Mimura, Nobuhide; Hagura, Ryoko.

    1996-01-01

    Diabetic nephropathy can be regarded mainly as a type of microangiopathy, but is a disease that may also include aspects of macroangiopathy. This is especially true of renal disease in non-insulin dependent diabetes mellitus (NIDDM), which is characterized not only by diabetic glomerulosclerosis, but also by atherosclerosis. We performed morphological studies on the kidney, using computed tomography (CT), focusing on such points as: abdominal aortic calcifications at the level of kidney, calcifications in the renal artery, and wedge-shaped defects on the renal surface. We noted that these findings became more prominent in NIDDM patients during end-stage renal failure than during normal renal function, and were significantly more common in those two NIDDM groups than in age-matched nondiabetic patients without hypertension, hyperlipidemia or gout. NIDDM patients exhibited these features more frequently than IDDM patients. (author)

  10. Lung cancer, analysis of the most frequent tomographic findings and histopathological correlation, in patients with primary pulmonary neoplasia diagnosed during the years 2011 and 2012, at the Hospital San Juan de Dios

    International Nuclear Information System (INIS)

    Cruz Romero, Cinthia

    2013-01-01

    Tomographic images, specifically the contrasted chest tomographies, were examined in patients diagnosed in patients diagnosed with lung cancer at the Hospital San Juan de Dios during the years 2011 and 2012. The primitive tomographic behavior of lung cancer was evaluated in order to determine and characterize its presentation pattern. Each histological type of lung cancer was determined. The stage of lung cancer was classified according to the International System of Staging Tumor, Node and Metastasis. An analysis of the incidence and stage of lung cancer at the time of diagnosis was made, evidencing the fundamental role of chest tomography in the screening, diagnosis, management and control of patients with primary pulmonary neoplasia [es

  11. Dense velocity reconstruction from tomographic PTV with material derivatives

    Science.gov (United States)

    Schneiders, Jan F. G.; Scarano, Fulvio

    2016-09-01

    A method is proposed to reconstruct the instantaneous velocity field from time-resolved volumetric particle tracking velocimetry (PTV, e.g., 3D-PTV, tomographic PTV and Shake-the-Box), employing both the instantaneous velocity and the velocity material derivative of the sparse tracer particles. The constraint to the measured temporal derivative of the PTV particle tracks improves the consistency of the reconstructed velocity field. The method is christened as pouring time into space, as it leverages temporal information to increase the spatial resolution of volumetric PTV measurements. This approach becomes relevant in cases where the spatial resolution is limited by the seeding concentration. The method solves an optimization problem to find the vorticity and velocity fields that minimize a cost function, which includes next to instantaneous velocity, also the velocity material derivative. The velocity and its material derivative are related through the vorticity transport equation, and the cost function is minimized using the limited-memory Broyden-Fletcher-Goldfarb-Shanno (L-BFGS) algorithm. The procedure is assessed numerically with a simulated PTV experiment in a turbulent boundary layer from a direct numerical simulation (DNS). The experimental validation considers a tomographic particle image velocimetry (PIV) experiment in a similar turbulent boundary layer and the additional case of a jet flow. The proposed technique (`vortex-in-cell plus', VIC+) is compared to tomographic PIV analysis (3D iterative cross-correlation), PTV interpolation methods (linear and adaptive Gaussian windowing) and to vortex-in-cell (VIC) interpolation without the material derivative. A visible increase in resolved details in the turbulent structures is obtained with the VIC+ approach, both in numerical simulations and experiments. This results in a more accurate determination of the turbulent stresses distribution in turbulent boundary layer investigations. Data from a jet

  12. 3D velocity measurements in a premixed flame by tomographic PIV

    International Nuclear Information System (INIS)

    Tokarev, M P; Sharaborin, D K; Lobasov, A S; Chikishev, L M; Dulin, V M; Markovich, D M

    2015-01-01

    Tomographic particle image velocimetry (PIV) has become a standard tool for 3D velocity measurements in non-reacting flows. However, the majority of the measurements in flows with combustion are limited to small resolved depth compared to the size of the field of view (typically 1 : 10). The limitations are associated with inhomogeneity of the volume illumination and the non-uniform flow seeding, the optical distortions and errors in the 3D calibration, and the unwanted flame luminosity. In the present work, the above constraints were overcome for the tomographic PIV experiment in a laminar axisymmetric premixed flame. The measurements were conducted for a 1 : 1 depth-to-size ratio using a system of eight CCD cameras and a 200 mJ pulsed laser. The results show that camera calibration based on the triangulation of the tracer particles in the non-reacting conditions provided reliable accuracy for the 3D image reconstruction in the flame. The modification of the tomographic reconstruction allowed a posteriori removal of unwanted bright objects, which were located outside of the region of interest but affected the reconstruction quality. This study reports on a novel experience for the instantaneous 3D velocimetry in laboratory-scale flames by using tomographic PIV. (paper)

  13. Computed tomography demonstration of a hypothalamic metastasis

    International Nuclear Information System (INIS)

    Chakeres, D.W.

    1983-01-01

    This case report describes a patient who presented with panhypopituitarism secondary to hypothalamic metastasis. A primary hypothalamic abnormality was suggested by computed tomographic (CT) demonstration of a small enhancing circular mass centered within the hypothalamus. Sellar radiographs and cerebral angiography were normal. (orig.)

  14. Computed tomography demonstration of a hypothalamic metastasis

    Energy Technology Data Exchange (ETDEWEB)

    Chakeres, D.W.

    1983-05-01

    This case report describes a patient who presented with panhypopituitarism secondary to hypothalamic metastasis. A primary hypothalamic abnormality was suggested by computed tomographic (CT) demonstration of a small enhancing circular mass centered within the hypothalamus. Sellar radiographs and cerebral angiography were normal.

  15. Ultrasound and multidetector computed tomography of mandibular ...

    African Journals Online (AJOL)

    Because of local invasivity and high metastatic potential, preoperative imaging evaluation of mandibular region and tumoral staging is essential along with biopsy sampling. The present manuscript describes the ultrasound and computed tomographic imaging findings of mandibular gland adenocarcinoma in two dogs and ...

  16. Nuclide imaging and computed tomography in cerebral vascular disease

    International Nuclear Information System (INIS)

    Chiu, L.C.; Christie, J.H.; Schapiro, R.L.

    1977-01-01

    This report presents our experience with computed tomographic and radionuclide scans in 224 patients with ischemic or hemorrhagic infarcts or intracerebral hematomas secondary to cerebral occlusive vascular diseases. The results vary according to the site of vascular occlusion. The radionuclide angiograms and static scintigrams show four distinct patterns in cases of occlusion of the middle cerebral artery. Computed tomographic scans exhibit less variation in appearance and have a higher sensitivity in cases of recent ischemic infarction. The ''tentorial confluence sign'' is an important finding on static scintigrams in patients with occipital infarction; if this sign is not present, this diagnosis should be suspect. Earlier reports have established the value of computed tomography and radionuclide scans in the evaluation of cerebral infarction. In individual cases, however, each of these modalities may render nondiagnostic or false negative findings; combining both types of examinations and comparing results yield a greater likelihood of an accurate diagnosis of cerebrovascular disease. Computed tomography is clearly more valuable than radionuclide scans in the diagnosis and follow-up of hemorrhagic infarcts or parenchymal hematomas

  17. Positron emission tomography/computed tomographic and magnetic resonance imaging in a murine model of progressive atherosclerosis using (64)Cu-labeled glycoprotein VI-Fc.

    Science.gov (United States)

    Bigalke, Boris; Phinikaridou, Alkystis; Andia, Marcelo E; Cooper, Margaret S; Schuster, Andreas; Schönberger, Tanja; Griessinger, Christoph M; Wurster, Thomas; Onthank, David; Ungerer, Martin; Gawaz, Meinrad; Nagel, Eike; Botnar, Rene M

    2013-11-01

    Plaque erosion leads to exposure of subendothelial collagen, which may be targeted by glycoprotein VI (GPVI). We aimed to detect plaque erosion using (64)Cu-labeled GPVI-Fc (fragment crystallized). Four-week-old male apolipoprotein E-deficient (ApoE(-/-)) mice (n=6) were fed a high-fat diet for 12 weeks. C57BL/6J wild-type (WT) mice served as controls (n=6). Another group of WT mice received a ligation injury of the left carotid artery (n=6) or sham procedure (n=4). All mice received a total activity of ≈12 MBq (64)Cu-GPVI-Fc by tail vein injection followed by delayed (24 hours) positron emission tomography using a NanoPET/computed tomographic scanner (Mediso, Hungary; Bioscan, USA) with an acquisition time of 1800 seconds. Seventy-two hours after positron emission tomography/computed tomography, all mice were scanned 2 hours after intravenous administration of 0.2 mmol/kg body weight of a gadolinium-based elastin-specific MR contrast agent. MRI was performed on a 3-T clinical scanner (Philips Healthcare, Best, The Netherlands). In ApoE(-/-) mice, the (64)Cu-GPVI-Fc uptake in the aortic arch was significantly higher compared with WT mice (ApoE(-/-): 13.2±1.5 Bq/cm(3) versus WT mice: 5.1±0.5 Bq/cm(3); P=0.028). (64)Cu-GPVI-Fc uptake was also higher in the injured left carotid artery wall compared with the intact right carotid artery of WT mice and as a trend compared with sham procedure (injured: 20.7±1.3 Bq/cm(3) versus intact: 2.3±0.5 Bq/cm(3); P=0.028 versus sham: 12.7±1.7 Bq/cm(3); P=0.068). Results were confirmed by ex vivo histology and in vivo MRI with elastin-specific MR contrast agent that measures plaque burden and vessel wall remodeling. Higher R1 relaxation rates were found in the injured carotid wall with a T1 mapping sequence (injured: 1.44±0.08 s(-1) versus intact: 0.91±0.02 s(-1); P=0.028 versus sham: 0.97±0.05 s(-1); P=0.068) and in the aortic arch of ApoE(-/-) mice compared with WT mice (ApoE(-/-): 1.49±0.05 s(-1) versus WT: 0.92±0.04 s

  18. Emission computer tomographic orthopan display of the jaws - method and normal values

    International Nuclear Information System (INIS)

    Bockisch, A.; Koenig, R.; Biersack, H.J.; Wahl, G.

    1990-01-01

    A tomoscintigraphic method is described to create orthopan-like projections of the jaws from SPECT bone scans using cylinder projection. On the basis of this projection a numerical analysis of the dental regions is performed in the same computer code. For each dental region the activity relative to the contralateral region and relative to the average activity of the corresponding jaw is calculated. Using this method, a set of normal activity relations has been established by investigation of 24 patients. (orig.) [de

  19. Pressure spectra from single-snapshot tomographic PIV

    NARCIS (Netherlands)

    Schneiders, J.F.G.; Avallone, F.; Pröbsting, S.; Ragni, D.; Scarano, F.

    2018-01-01

    The power spectral density and coherence of temporal pressure fluctuations are obtained from low-repetition-rate tomographic PIV measurements. This is achieved by extension of recent single-snapshot pressure evaluation techniques based upon the Taylor’s hypothesis (TH) of frozen turbulence and

  20. An industrial application of computer assisted tomography

    International Nuclear Information System (INIS)

    Tonner, P.D.; Tosello, G.

    1984-10-01

    Computer assisted tomography (CAT) scanning is a nondestructive testing technique used to obtain quantitatively accurate mappings of the distribution of linear attenuation coefficients inside an object. To demonstrate the potential of the technique for accurately locating defects in three dimensions a sectioned 5 cm gate valve, with a shrink cavity made visible by the sectioning, was tomographically imaged using a Co-60 source. The tomographic images revealed a larger cavity below the sectioned surface. The position of this cavity was located with an in-plane and axial precision of approximately +- 1 mm. The volume of the cavity was estimated to be approximately 40 mm 3

  1. Computer-aided Detection of Lung Cancer on Chest Radiographs: Effect on Observer Performance

    NARCIS (Netherlands)

    de Hoop, Bartjan; de Boo, Diederik W.; Gietema, Hester A.; van Hoorn, Frans; Mearadji, Banafsche; Schijf, Laura; van Ginneken, Bram; Prokop, Mathias; Schaefer-Prokop, Cornelia

    2010-01-01

    Purpose: To assess how computer-aided detection (CAD) affects reader performance in detecting early lung cancer on chest radiographs. Materials and Methods: In this ethics committee-approved study, 46 individuals with 49 computed tomographically (CT)-detected and histologically proved lung cancers

  2. Tomographic Particle Image Velocimetry Using Colored Shadow Imaging

    KAUST Repository

    Alarfaj, Meshal K.

    2016-02-01

    Tomographic Particle Image Velocimetry Using Colored Shadow Imaging by Meshal K Alarfaj, Master of Science King Abdullah University of Science & Technology, 2015 Tomographic Particle image velocimetry (PIV) is a recent PIV method capable of reconstructing the full 3D velocity field of complex flows, within a 3-D volume. For nearly the last decade, it has become the most powerful tool for study of turbulent velocity fields and promises great advancements in the study of fluid mechanics. Among the early published studies, a good number of researches have suggested enhancements and optimizations of different aspects of this technique to improve the effectiveness. One major aspect, which is the core of the present work, is related to reducing the cost of the Tomographic PIV setup. In this thesis, we attempt to reduce this cost by using an experimental setup exploiting 4 commercial digital still cameras in combination with low-cost Light emitting diodes (LEDs). We use two different colors to distinguish the two light pulses. By using colored shadows with red and green LEDs, we can identify the particle locations within the measurement volume, at the two different times, thereby allowing calculation of the velocities. The present work tests this technique on the flows patterns of a jet ejected from a tube in a water tank. Results from the images processing are presented and challenges discussed.

  3. Computerized tomographic diagnosis of basal skull fracture

    International Nuclear Information System (INIS)

    Tanaka, Tokutaro; Shimoyama, Ichiro; Endoh, Mitsutoshi; Ninchoji, Toshiaki; Uemura, Kenichi.

    1984-01-01

    The diagnosis of basal skull fractures used to be difficult, particularly on the basis of routine skull roentgenography alone. We have now examined the diagnostic value of conventional computerized tomography in basal skull fractures. We studied 82 cases clinically diagnosed as basal skull fractures. We examined them based on at least one of the following computerized tomographic criteria for basal skull fractures: 1) fracture line(s), 2) intracranial air, 3) fluid in the paranasal sinuses, and 4) fluid in the middle ear, including the mastoid air cells. The signs of the fracture line and of the intracranial air are definite indications of basal skull fracture, but the signs of fluid in the paranasal sinuses and/or in the middle ear are not definite. When combined, however, with such other clinical signs as black eye, Battle's sign, CSF leakage, CSF findings, and profuse nasal or ear bleeding, the diagnosis is more reliable. Seventy cases (85.4%) in this series had basal skull fractures according to our computerized tomographic criteria. Among them , 26 cases (31.7%) were diagnosed with fracture lines, 17 cases (20.7%) with intracranial air, 16 cases (19.5%) with fluid in the paranasal sinuses, 10 cases (12.2%) with fluid in the middle ear, and one case (1.2%) with fluid in both. Twelve cases (14.6%) of the 82 cases clinically diagnosed as basal skull fractures could not have been diagnosed on our computerized tomographic criteria alone. We diagnosed them because of CSF leakage, CSF findings, surgical findings, etc. (author)

  4. Rapid estimation of split renal function in kidney donors using software developed for computed tomographic renal volumetry

    International Nuclear Information System (INIS)

    Kato, Fumi; Kamishima, Tamotsu; Morita, Ken; Muto, Natalia S.; Okamoto, Syozou; Omatsu, Tokuhiko; Oyama, Noriko; Terae, Satoshi; Kanegae, Kakuko; Nonomura, Katsuya; Shirato, Hiroki

    2011-01-01

    Purpose: To evaluate the speed and precision of split renal volume (SRV) measurement, which is the ratio of unilateral renal volume to bilateral renal volume, using a newly developed software for computed tomographic (CT) volumetry and to investigate the usefulness of SRV for the estimation of split renal function (SRF) in kidney donors. Method: Both dynamic CT and renal scintigraphy in 28 adult potential living renal donors were the subjects of this study. We calculated SRV using the newly developed volumetric software built into a PACS viewer (n-SRV), and compared it with SRV calculated using a conventional workstation, ZIOSOFT (z-SRV). The correlation with split renal function (SRF) using 99m Tc-DMSA scintigraphy was also investigated. Results: The time required for volumetry of bilateral kidneys with the newly developed software (16.7 ± 3.9 s) was significantly shorter than that of the workstation (102.6 ± 38.9 s, p < 0.0001). The results of n-SRV (49.7 ± 4.0%) were highly consistent with those of z-SRV (49.9 ± 3.6%), with a mean discrepancy of 0.12 ± 0.84%. The SRF also agreed well with the n-SRV, with a mean discrepancy of 0.25 ± 1.65%. The dominant side determined by SRF and n-SRV showed agreement in 26 of 28 cases (92.9%). Conclusion: The newly developed software for CT volumetry was more rapid than the conventional workstation volumetry and just as accurate, and was suggested to be useful for the estimation of SRF and thus the dominant side in kidney donors.

  5. A study of the decoding of multiple pinhole coded aperture RI tomographic images

    International Nuclear Information System (INIS)

    Hasegawa, Takeo; Kobayashi, Akitoshi; Nishiyama, Yutaka; Akagi, Kiyoshi; Uehata, Hiroshi

    1981-01-01

    In order to obtain a radioisotope (RI) tomographic image, there are various, methods, including the RCT method, Time Modulate method, and Multiple Pinhole Coded Aperture (MPCA) method and others. The MPCA method has several advantages. Using the MPCA method, there is no need to move either the detector or the patient, Furthermore, the generally used γ-camera may be used without any alterations. Due to certain problems in reconstructing the tomographic image, the use of the MPCA method in clinical practice is limited to representation of small organs (e.g. heart) using the 7-Pinhole collimator. This research presents an experimental approach to overcome the problems in reconstruction of tomographic images of large organs (organs other than the heart, such as the brain, liver, lung etc.) by introducing a reconstruction algorithm and correction software into the MPCA method. There are 2 main problems in MPCA image reconstruction: (1) Due to the rounding-off procedure, there is both point omission and shifting of point coordinates. (2) The central portion is characterized by high-counts. Both of these problems were solved by incorporating a reconstruction algorithm and a correction function. The resultant corrected tomographic image was processed using a filter derived from subjecting a PSF to a Fourier transform. Thus, it has become possible to obtain a high-quality tomographic image of large organs for clinical use. (author)

  6. 99mTc-DMSA renal uptake in urological diseases measured from renal tomographic images using single photon emission computed tomography (SPECT)

    International Nuclear Information System (INIS)

    Oishi, Yukihiko; Tashiro, Kazuya; Kishimoto, Koichi; Wada, Tetsuro; Torii, Shinichiro; Yoshigoe, Fukuo; Machida, Toyohei; Yamada, Hideo; Toyama, Hinako.

    1987-01-01

    To determine renal function, 99m Tc-DMSA renal uptake was measured from renal tomographic images obtained by single photon emission computed tomography (SPECT). A total of 77 tests was conducted on 73 patients with various diseases in the kidneys and urinary tract to determine renal uptake. The correlation coefficient(r) between total renal volume and total renal uptake was 0.3509 and that between renal volume and uptake of 143 kidneys was 0.5433. In 62 patients whose creatinine clearance could be measured, the correlation coefficient between creatinine clearance and total renal volume was 0.2352, and that between creatinine clearance and total renal uptake was 0.8854, that is, creatinine clearance correlated well with renal uptake. Renal volume and uptake determined in 10 normal male and 10 normal female adults were 220 ml and 26.8 % for the right kidney and 239 ml and 27.6 % for the left kidney for the males and 206 ml and 26.4 % (right) and 237 ml and 27.9 % (left) for the females. This method, which requires no blood or urine collection, is very useful as an individual kidney function test to evaluate individual kidney function and to understand kidney function before and after operation in patients with renal and urinary diseases. (author)

  7. Comparative validation of the radiographic and tomographic measurement of patellar height

    Directory of Open Access Journals (Sweden)

    Marco Antonio Schueda

    2013-09-01

    Full Text Available OBJECTIVE: To evaluate and validate the radiographic measurement of patellar height with computerized tomography scans. METHODS: Measured the patellar height through the lateral radiographic image supported by one foot and sagittal tomographic view of the knee in extension, flexion of 20°, and quadriceps contraction of 40 patients (80 knees, asymptomatic and no history of knee injuries using Insall-Salvati index. There were 20 adult females and 20 adult males. RESULTS: The height patellar index was higher in women of all images taken, in proportion. There was no statistical difference of patellar height index between the radiographics and tomographics images. CONCLUSION: The Insall-Salvati index in females was higher in all cases evaluated. Furthermore, it is possible to measure the patellar height index during tomographic study without distorting the results obtained, using to define the presence of patella alta or patella baja.

  8. Quantum probability measures and tomographic probability densities

    NARCIS (Netherlands)

    Amosov, GG; Man'ko, [No Value

    2004-01-01

    Using a simple relation of the Dirac delta-function to generalized the theta-function, the relationship between the tomographic probability approach and the quantum probability measure approach with the description of quantum states is discussed. The quantum state tomogram expressed in terms of the

  9. Computed Tomography Status

    Science.gov (United States)

    Hansche, B. D.

    1983-01-01

    Computed tomography (CT) is a relatively new radiographic technique which has become widely used in the medical field, where it is better known as computerized axial tomographic (CAT) scanning. This technique is also being adopted by the industrial radiographic community, although the greater range of densities, variation in samples sizes, plus possible requirement for finer resolution make it difficult to duplicate the excellent results that the medical scanners have achieved.

  10. Impact of Collateral Status Evaluated by Dynamic Computed Tomographic Angiography on Clinical Outcome in Patients With Ischemic Stroke.

    Science.gov (United States)

    van den Wijngaard, Ido R; Boiten, Jelis; Holswilder, Ghislaine; Algra, Ale; Dippel, Diederik W J; Velthuis, Birgitta K; Wermer, Marieke J H; van Walderveen, Marianne A A

    2015-12-01

    Status of collateral circulation is a strong predictor of outcome after acute ischemic stroke. Our aim was to compare the predictive value of strategies for collateral blood flow assessment with dynamic computed tomographic angiography (CTA) and conventional single-phase CT angiography. Patients with a proximal middle cerebral artery occlusion underwent noncontrast CT, single-phase CTA and whole brain CT perfusion/dynamic CTA within 9 hours after stroke onset. We defined poor outcome as a score on the modified Rankin Scale score of ≥3. The association between collateral score and clinical outcome at 3 months was analyzed with Poisson regression. The prognostic value of collateral scoring with dynamic CTA and single-phase CTA in addition to age, stroke severity, and noncontrast CT was assessed with logistic regression and summarized with the area under the curve. Seventy patients were included, with a mean age of 68 years. We observed an increased risk of poor outcome in patients with poor collaterals on single-phase CTA (risk ratio, 1.8; 95% confidence interval, 1.0-3.1) and on dynamic CTA (risk ratio, 2.0; 95% confidence interval, 1.5-2.7). The prediction of poor clinical outcome by means of collateral adjustment was better with dynamic CTA (area under the curve, 0.84; likelihood ratio test PCollateral assessment with dynamic CTA better predicts clinical outcome at 3 months than single-phase conventional CTA. URL: http://www.trialregister.nl/trialreg. Unique identifier: NTR1804. URL: http://www.clinicaltrials.gov. Unique identifier: NCT00880113. © 2015 American Heart Association, Inc.

  11. Tomographic reconstruction of atmospheric volumes from infrared limb-imager measurements

    Energy Technology Data Exchange (ETDEWEB)

    Ungermann, Joern

    2011-08-12

    State-of-the art nadir and limb-sounders, but also in situ measurements, do not offer the capability to highly resolve the atmosphere in all three dimensions. This leaves an observational gap with respect to small-scale structures that arise frequently in the atmosphere and that still lack a quantitative understanding. For instance, filaments and tropopause folds in the upper troposphere and lower stratosphere (UTLS) are crucial for its composition and variability. One way to achieve a highly resolved three-dimensional (3-D) picture of the atmosphere is the tomographic evaluation of limb-imager measurements. This thesis presents a methodology for the tomographic reconstruction of atmospheric constituents. To be able to deal with the large increase of observations and unknowns compared to conventional retrievals, great care is taken to reduce memory consumption and processing time. This method is used to evaluate the performance of two upcoming infrared limb-imager instruments and to prepare their missions. The first examined instrument is the infrared limb-imager on board of PREMIER (Process Exploration through Measurements of Infrared and millimetrewave Emitted Radiation), one of three remaining candidates for ESA's 7th Earth Explorer mission. Scientific goals of PREMIER are, among others, the examination of gravity waves and the quantification of processes controlling atmospheric composition in the UTLS, a region of particular importance for climate change. Simulations based on the performance requirements of this instrument deliver a vertical resolution that is slightly better than its vertical field-of-view (about 0.75 km) and a horizontal resolution of {approx}25km x 70 km. Non-linear end-to-end simulations for various gravity wave patterns demonstrate that the high 3-D resolution of PREMIER considerably extends the range of detectable gravity waves in terms of horizontal and vertical wavelength compared to previous observations. The second examined

  12. Tomographic reconstruction of atmospheric volumes from infrared limb-imager measurements

    Energy Technology Data Exchange (ETDEWEB)

    Ungermann, Joern

    2011-08-12

    State-of-the art nadir and limb-sounders, but also in situ measurements, do not offer the capability to highly resolve the atmosphere in all three dimensions. This leaves an observational gap with respect to small-scale structures that arise frequently in the atmosphere and that still lack a quantitative understanding. For instance, filaments and tropopause folds in the upper troposphere and lower stratosphere (UTLS) are crucial for its composition and variability. One way to achieve a highly resolved three-dimensional (3-D) picture of the atmosphere is the tomographic evaluation of limb-imager measurements. This thesis presents a methodology for the tomographic reconstruction of atmospheric constituents. To be able to deal with the large increase of observations and unknowns compared to conventional retrievals, great care is taken to reduce memory consumption and processing time. This method is used to evaluate the performance of two upcoming infrared limb-imager instruments and to prepare their missions. The first examined instrument is the infrared limb-imager on board of PREMIER (Process Exploration through Measurements of Infrared and millimetrewave Emitted Radiation), one of three remaining candidates for ESA's 7th Earth Explorer mission. Scientific goals of PREMIER are, among others, the examination of gravity waves and the quantification of processes controlling atmospheric composition in the UTLS, a region of particular importance for climate change. Simulations based on the performance requirements of this instrument deliver a vertical resolution that is slightly better than its vertical field-of-view (about 0.75 km) and a horizontal resolution of {approx}25km x 70 km. Non-linear end-to-end simulations for various gravity wave patterns demonstrate that the high 3-D resolution of PREMIER considerably extends the range of detectable gravity waves in terms of horizontal and vertical wavelength compared to previous observations. The second examined instrument

  13. Analysis of iterative region-of-interest image reconstruction for x-ray computed tomography.

    Science.gov (United States)

    Sidky, Emil Y; Kraemer, David N; Roth, Erin G; Ullberg, Christer; Reiser, Ingrid S; Pan, Xiaochuan

    2014-10-03

    One of the challenges for iterative image reconstruction (IIR) is that such algorithms solve an imaging model implicitly, requiring a complete representation of the scanned subject within the viewing domain of the scanner. This requirement can place a prohibitively high computational burden for IIR applied to x-ray computed tomography (CT), especially when high-resolution tomographic volumes are required. In this work, we aim to develop an IIR algorithm for direct region-of-interest (ROI) image reconstruction. The proposed class of IIR algorithms is based on an optimization problem that incorporates a data fidelity term, which compares a derivative of the estimated data with the available projection data. In order to characterize this optimization problem, we apply it to computer-simulated two-dimensional fan-beam CT data, using both ideal noiseless data and realistic data containing a level of noise comparable to that of the breast CT application. The proposed method is demonstrated for both complete field-of-view and ROI imaging. To demonstrate the potential utility of the proposed ROI imaging method, it is applied to actual CT scanner data.

  14. Deviations of Mesial Root Canals of Mandibular First Molar Teeth at the Apical Third: A Micro-computed Tomographic Study.

    Science.gov (United States)

    Keles, Ali; Keskin, Cangül

    2018-04-19

    The present study aimed to quantitatively analyze apical foramen deviations of mesial root canals of mandibular first molar teeth by means of micro-computed tomographic (micro-CT) imaging. Micro-CT images of the mesial roots of 109 mandibular first molar teeth with independent mesiobuccal (MB) and mesiolingual (ML) root canals were analyzed. The deviations of the apical foramina of the MB, ML, and middle mesial root canals from the anatomic apex were measured. The vertical distance between the apical foramina of each mesial root canal in relation to each other was also calculated. The distances from the apical foramina of the MB, ML, and middle mesial root canals to the anatomic apex of the mesial root were up to 2.51 mm, 3.21 mm, and 5.67 mm, respectively. There was no significant difference between the deviations of MB and ML root canals from each other (P > .05). The middle mesial root canal showed the greatest deviation compared with the MB and ML canals (P < .05). The apical foramina of mesial root canals of mandibular first molar teeth showed greater variations from each other and anatomic apices than previously reported. Clinically, the use of electronic apex locators for the detection of minor apical foramen of each mesial root canal is of the utmost important. Copyright © 2018 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  15. Impact of Cardiac Computed Tomographic Angiography Findings on Planning of Cancer Therapy in Patients with Concomitant Structural Heart Disease

    Directory of Open Access Journals (Sweden)

    Iyad N. Daher

    2011-01-01

    Full Text Available Background. Exclusion of underlying coronary artery disease (CAD is essential in the diagnosis of chemotherapy-induced cardiomyopathy. Presence and severity of CAD can also impact the choice of therapy in cancer patients. The value of cardiac computed tomographic angiography (CCTA in this setting has not been reported. Methods. We collected data on the clinical presentation and indications for CCTA performed from January to December 2008 at the University of Texas MD Anderson Cancer Center (MDACC. All examinations were performed using a 64-detector scanner. CCTA results and subsequent treatment decisions were examined. Results. A total of 80 patients underwent CCTA during the study period for the following indications (not mutually exclusive: cardiomyopathy of unknown etiology in 33 pts (41.3%, chest pain in 32 (40.0%, abnormal stress test in 16 (20.0%, abnormal cardiac markers in 8 (10.0%, suspected cardiac mass or thrombus in 7 (8.8%. Chemotherapy-induced cardiomyopathy was diagnosed in 18 pts (22.5%. Severe CAD was detected in 22 pts (27.5%; due to concomitant advanced cancer or patient refusal, only 12 underwent coronary angiogram. Of these, 4 pts (5% of total underwent coronary artery bypass grafting. A total of 41 pts (51.3% had their cancer management altered based on CCTA findings. Conclusion. CCTA is useful in evaluating cancer pts with structural heart disease and can have an impact on the management of cancer and cardiac disease.

  16. Lung Ultrasonography in Patients With Idiopathic Pulmonary Fibrosis: Evaluation of a Simplified Protocol With High-Resolution Computed Tomographic Correlation.

    Science.gov (United States)

    Vassalou, Evangelia E; Raissaki, Maria; Magkanas, Eleftherios; Antoniou, Katerina M; Karantanas, Apostolos H

    2018-03-01

    To compare a simplified ultrasonographic (US) protocol in 2 patient positions with the same-positioned comprehensive US assessments and high-resolution computed tomographic (CT) findings in patients with idiopathic pulmonary fibrosis. Twenty-five consecutive patients with idiopathic pulmonary fibrosis were prospectively enrolled and examined in 2 sessions. During session 1, patients were examined with a US protocol including 56 lung intercostal spaces in supine/sitting (supine/sitting comprehensive protocol) and lateral decubitus (decubitus comprehensive protocol) positions. During session 2, patients were evaluated with a 16-intercostal space US protocol in sitting (sitting simplified protocol) and left/right decubitus (decubitus simplified protocol) positions. The 16 intercostal spaces were chosen according to the prevalence of idiopathic pulmonary fibrosis-related changes on high-resolution CT. The sum of B-lines counted in each intercostal space formed the US scores for all 4 US protocols: supine/sitting and decubitus comprehensive US scores and sitting and decubitus simplified US scores. High-resolution CT-related Warrick scores (J Rheumatol 1991; 18:1520-1528) were compared to US scores. The duration of each protocol was recorded. A significant correlation was found between all US scores and Warrick scores and between simplified and corresponding comprehensive scores (P idiopathic pulmonary fibrosis. The 16-intercostal space simplified protocol in the lateral decubitus position correlated better with high-resolution CT findings and was less time-consuming compared to the sitting position. © 2017 by the American Institute of Ultrasound in Medicine.

  17. Computational Music Analysis

    DEFF Research Database (Denmark)

    This book provides an in-depth introduction and overview of current research in computational music analysis. Its seventeen chapters, written by leading researchers, collectively represent the diversity as well as the technical and philosophical sophistication of the work being done today...... on well-established theories in music theory and analysis, such as Forte's pitch-class set theory, Schenkerian analysis, the methods of semiotic analysis developed by Ruwet and Nattiez, and Lerdahl and Jackendoff's Generative Theory of Tonal Music. The book is divided into six parts, covering...... music analysis, the book provides an invaluable resource for researchers, teachers and students in music theory and analysis, computer science, music information retrieval and related disciplines. It also provides a state-of-the-art reference for practitioners in the music technology industry....

  18. Computed tomographic diagnosis of the splenic trauma

    International Nuclear Information System (INIS)

    Suzuki, Masayuki; Takashima, Tsutomu; Funaki, Hiromi; Uogishi, Makoto; Isobe, Tsugimasa; Kanno, Shoichi; Ushitani, Kenji; Fuchuh, Kosei; Sakita, Tsuyoshi.

    1985-01-01

    Three cases (3-year-old, 51-year-old and 17-year-old males) in which splenic trauma was diagnosed by plain computed tomography (CT) are presented. CT images revealed retention of fluid in the abdominal cavity in all cases and clear splenic hematoma and laceration in one case. CT is superior in the visualization of splenic hematoma and hemorrhage in the abdominal cavity accompanied by splenic trauma. It should, however, be noted that the presence of laceration is frequently difficult to detect due to artifacts. Indication for surgery should be decided by evaluating the severity of clinical symptoms. (Namekawa, K.)

  19. Computed tomographic diagnosis of the splenic trauma

    Energy Technology Data Exchange (ETDEWEB)

    Suzuki, Masayuki; Takashima, Tsutomu; Funaki, Hiromi; Uogishi, Makoto; Isobe, Tsugimasa; Kanno, Shoichi; Ushitani, Kenji; Fuchuh, Kosei; Sakita, Tsuyoshi

    1985-01-01

    Three cases (3-year-old, 51-year-old and 17-year-old males) in which splenic trauma was diagnosed by plain computed tomography (CT) are presented. CT images revealed retention of fluid in the abdominal cavity in all cases and clear splenic hematoma and laceration in one case. CT is superior in the visualization of splenic hematoma and hemorrhage in the abdominal cavity accompanied by splenic trauma. It should, however, be noted that the presence of laceration is frequently difficult to detect due to artifacts. Indication for surgery should be decided by evaluating the severity of clinical symptoms. (Namekawa, K.).

  20. Time-resolved tomographic images of a relativistic electron beam

    International Nuclear Information System (INIS)

    Koehler, H.A.; Jacoby, B.A.; Nelson, M.

    1984-07-01

    We obtained a sequential series of time-resolved tomographic two-dimensional images of a 4.5-MeV, 6-kA, 30-ns electron beam. Three linear fiber-optic arrays of 30 or 60 fibers each were positioned around the beam axis at 0 0 , 61 0 , and 117 0 . The beam interacting with nitrogen at 20 Torr emitted light that was focused onto the fiber arrays and transmitted to a streak camera where the data were recorded on film. The film was digitized, and two-dimensional images were reconstructed using the maximum-entropy tomographic technique. These images were then combined to produce an ultra-high-speed movie of the electron-beam pulse

  1. Computed-tomographic and conventional linear-tomographic evaluation of tracheobronchial lesions for laser photoresection

    International Nuclear Information System (INIS)

    Pearlberg, J.L.; Sandler, M.A.; Kvale, P.; Beute, G.H.; Madrazo, B.L.

    1985-01-01

    Laser therapy is a new modality for treatment of airway lesions. The authors examined 18 patients prior to laser photoresection of tracheobronchial lesions. Thirteen had cancers involving the distal trachea, carina, and/or proximal bronchi; five had benign lesions of the middle or proximal trachea. Each patient was examined by conventional linear tomography (CLT) and computed tomography (CT). CT was valuable in patients who had lesions of the distal trachea, carina, and/or proximal bronchi. Its particular usefulness, and its advantage relative to CLT, consisted in its ability to delineate vascular structures adjacent to the planned area of photoresection. Neither CLT nor CT was helpful in evaluation of benign lesions of the proximal trachea

  2. 3D galaxy clustering with future wide-field surveys: Advantages of a spherical Fourier-Bessel analysis

    Science.gov (United States)

    Lanusse, F.; Rassat, A.; Starck, J.-L.

    2015-06-01

    Context. Upcoming spectroscopic galaxy surveys are extremely promising to help in addressing the major challenges of cosmology, in particular in understanding the nature of the dark universe. The strength of these surveys, naturally described in spherical geometry, comes from their unprecedented depth and width, but an optimal extraction of their three-dimensional information is of utmost importance to best constrain the properties of the dark universe. Aims: Although there is theoretical motivation and novel tools to explore these surveys using the 3D spherical Fourier-Bessel (SFB) power spectrum of galaxy number counts Cℓ(k,k'), most survey optimisations and forecasts are based on the tomographic spherical harmonics power spectrum C(ij)_ℓ. The goal of this paper is to perform a new investigation of the information that can be extracted from these two analyses in the context of planned stage IV wide-field galaxy surveys. Methods: We compared tomographic and 3D SFB techniques by comparing the forecast cosmological parameter constraints obtained from a Fisher analysis. The comparison was made possible by careful and coherent treatment of non-linear scales in the two analyses, which makes this study the first to compare 3D SFB and tomographic constraints on an equal footing. Nuisance parameters related to a scale- and redshift-dependent galaxy bias were also included in the computation of the 3D SFB and tomographic power spectra for the first time. Results: Tomographic and 3D SFB methods can recover similar constraints in the absence of systematics. This requires choosing an optimal number of redshift bins for the tomographic analysis, which we computed to be N = 26 for zmed ≃ 0.4, N = 30 for zmed ≃ 1.0, and N = 42 for zmed ≃ 1.7. When marginalising over nuisance parameters related to the galaxy bias, the forecast 3D SFB constraints are less affected by this source of systematics than the tomographic constraints. In addition, the rate of increase of the

  3. An efficient reconstruction algorithm for differential phase-contrast tomographic images from a limited number of views

    International Nuclear Information System (INIS)

    Sunaguchi, Naoki; Yuasa, Tetsuya; Gupta, Rajiv; Ando, Masami

    2015-01-01

    The main focus of this paper is reconstruction of tomographic phase-contrast image from a set of projections. We propose an efficient reconstruction algorithm for differential phase-contrast computed tomography that can considerably reduce the number of projections required for reconstruction. The key result underlying this research is a projection theorem that states that the second derivative of the projection set is linearly related to the Laplacian of the tomographic image. The proposed algorithm first reconstructs the Laplacian image of the phase-shift distribution from the second-derivative of the projections using total variation regularization. The second step is to obtain the phase-shift distribution by solving a Poisson equation whose source is the Laplacian image previously reconstructed under the Dirichlet condition. We demonstrate the efficacy of this algorithm using both synthetically generated simulation data and projection data acquired experimentally at a synchrotron. The experimental phase data were acquired from a human coronary artery specimen using dark-field-imaging optics pioneered by our group. Our results demonstrate that the proposed algorithm can reduce the number of projections to approximately 33% as compared with the conventional filtered backprojection method, without any detrimental effect on the image quality

  4. An introduction to the tomographic picture of quantum mechanics

    International Nuclear Information System (INIS)

    Ibort, A; Man'ko, V I; Marmo, G; Simoni, A; Ventriglia, F

    2009-01-01

    Starting from the famous Pauli problem on the possibility of associating quantum states with probabilities, the formulation of quantum mechanics in which quantum states are described by fair probability distributions (tomograms, i.e. tomographic probabilities) is reviewed in a pedagogical style. The relation between the quantum state description and the classical state description is elucidated. The difference between those sets of tomograms is described by inequalities equivalent to a complete set of uncertainty relations for the quantum domain and to non-negativity of probability density on phase space in the classical domain. The intersection of such sets is studied. The mathematical mechanism that allows us to construct different kinds of tomographic probabilities like symplectic tomograms, spin tomograms, photon number tomograms, etc is clarified and a connection with abstract Hilbert space properties is established. The superposition rule and uncertainty relations in terms of probabilities as well as quantum basic equations like quantum evolution and energy spectra equations are given in an explicit form. A method to check experimentally the uncertainty relations is suggested using optical tomograms. Entanglement phenomena and the connection with semigroups acting on simplexes are studied in detail for spin states in the case of two-qubits. The star-product formalism is associated with the tomographic probability formulation of quantum mechanics.

  5. Field experience with a mobile tomographic nondestructive assay system

    International Nuclear Information System (INIS)

    Prettyman, T.H.; Betts, S.E.; Taggart, D.P.; Estep, R.J.; Nicholas, N.J.; Lucas, M.C.; Harlan, R.A.

    1995-01-01

    A mobile tomographic gamma-ray scanner (TGS) developed by Los Alamos National Laboratory was recently demonstrated at the Rocky Flats Environmental Technology Site and is currently in use at Los Alamos waste storage areas. The scanner was developed to assay radionuclides in low-level, transuranic, and mixed waste in containers ranging in size from 2 ft 3 boxes to 83-gallon overpacks. The tomographic imaging capability provides a complete correction for source distribution and matrix attenuation effects, enabling accurate assays of Pu-239 and other gamma-ray emitting isotopes. In addition, the system can reliably detect self-absorbing material such as plutonium metal shot, and can correct for bias caused by self-absorption. The system can be quickly configured to execute far-field scans, segmented gamma-ray scans, and a host of intermediate scanning protocols, enabling higher throughput (up to 20 drums per 8-hour shift). In this paper, we will report on the results of field trials of the mobile system at Rocky Flats and Los Alamos. Assay accuracy is confirmed for cases in which TGS assays can be compared with assays (e.g. with calorimetry) of individual packages within the drums. The mobile tomographic technology is expected to considerably reduce characterization costs at DOE production and environmental technology sites

  6. Cranium-brain trauma in computed tomographs - diagnosis and clinical correlation

    International Nuclear Information System (INIS)

    Wrasse, K.

    1982-01-01

    For the successful treatment of intracranial complications in the case of cranium-brain trauma a quick and exact diagnosis is necessary. The goal of this work was to test and evaluate the effectivity of computed tomography for neurotraumatology. Using 565 patients, who were acutely or at one time suffering from a cranium-brain trauma, the high validity of computed tomography for these injuries was proven. The following areas in question were studied with respect to the value of computed tomography in comparison to them: angiography, X-ray diagnostic, echoencephalography, brain scintigraphy, electroencephalography and neurological-psychopathological findings from cranium-brain trauma. Statement possibilities and difficulties of computed tomography are discussed in the cases of the following neurotraumatological diseases: extracranial hematomas; acute cranium-brain traumas; traumatic arachnoidal bleeding; diffuse brain edema; transtentorial herniation and brain contusions. At the end the diagnostic and therapeutic procedures in the case of cranium-brain trauma are presented. (orig.) [de

  7. Visual servoing in medical robotics: a survey. Part II: tomographic imaging modalities--techniques and applications.

    Science.gov (United States)

    Azizian, Mahdi; Najmaei, Nima; Khoshnam, Mahta; Patel, Rajni

    2015-03-01

    Intraoperative application of tomographic imaging techniques provides a means of visual servoing for objects beneath the surface of organs. The focus of this survey is on therapeutic and diagnostic medical applications where tomographic imaging is used in visual servoing. To this end, a comprehensive search of the electronic databases was completed for the period 2000-2013. Existing techniques and products are categorized and studied, based on the imaging modality and their medical applications. This part complements Part I of the survey, which covers visual servoing techniques using endoscopic imaging and direct vision. The main challenges in using visual servoing based on tomographic images have been identified. 'Supervised automation of medical robotics' is found to be a major trend in this field and ultrasound is the most commonly used tomographic modality for visual servoing. Copyright © 2014 John Wiley & Sons, Ltd.

  8. A comparison of newborn stylized and tomographic models for dose assessment in paediatric radiology

    International Nuclear Information System (INIS)

    Staton, R J; Pazik, F D; Nipper, J C; Williams, J L; Bolch, W E

    2003-01-01

    Establishment of organ doses from diagnostic and interventional examinations is a key component to quantifying the radiation risks from medical exposures and for formulating corresponding dose-reduction strategies. Radiation transport models of human anatomy provide a convenient method for simulating radiological examinations. At present, two classes of models exist: stylized mathematical models and tomographic voxel models. In the present study, organ dose comparisons are made for projection radiographs of both a stylized and a tomographic model of the newborn patient. Sixteen separate radiographs were simulated for each model at x-ray technique factors typical of newborn examinations: chest, abdomen, thorax and head views in the AP, PA, left LAT and right LAT projection orientation. For AP and PA radiographs of the torso (chest, abdomen and thorax views), the effective dose assessed for the tomographic model exceeds that for the stylized model with per cent differences ranging from 19% (AP abdominal view) to 43% AP chest view. In contrast, the effective dose for the stylized model exceeds that for the tomographic model for all eight lateral views including those of the head, with per cent differences ranging from 9% (LLAT chest view) to 51% (RLAT thorax view). While organ positioning differences do exist between the models, a major factor contributing to differences in effective dose is the models' exterior trunk shape. In the tomographic model, a more elliptical shape is seen thus providing for less tissue shielding for internal organs in the AP and PA directions, with corresponding increased tissue shielding in the lateral directions. This observation is opposite of that seen in comparisons of stylized and tomographic models of the adult

  9. X-ray Tomographic Microscopy at TOMCAT

    Energy Technology Data Exchange (ETDEWEB)

    Marone, F; Hintermueller, C; McDonald, S; Abela, R; Mikuljan, G; Isenegger, A; Stampanoni, M, E-mail: federica.marone@psi.c [Swiss Light Source, Paul Scherrer Institut, 5232 Villigen (Switzerland)

    2009-09-01

    Synchrotron-based X-ray Tomographic Microscopy is a powerful technique for fast non-destructive, high resolution quantitative volumetric investigations on diverse samples. At the TOMCAT (TOmographic Microscopy and Coherent rAdiology experimenTs) beamline at the Swiss Light Source, synchrotron light is delivered by a 2.9 T superbend. The main optical component, a Double Crystal Multilayer Monochromator, covers an energy range between 8 and 45 keV. The standard TOMCAT detector offers field of views ranging from 0.75x0.75 mm{sup 2} up to 12.1x12.1 mm{sup 2} with a pixel size of 0.37 {mu}m and 5.92 {mu}m, respectively. In addition to routine measurements, which exploit the absorption contrast, the high coherence of the source also enables phase contrast tomography, implemented with two complementary techniques (Modified Transport of Intensity approach and Grating Interferometry). Typical acquisition times for a tomogram are in the order of few minutes, ensuring high throughput and allowing for semi-dynamical investigations. Raw data are automatically post-processed online and full reconstructed volumes are available shortly after a scan with minimal user intervention.

  10. Computed tomography: ocular manifestations in acute head injury ...

    African Journals Online (AJOL)

    Background: Acute head injuries are common in the population. Associated ocular injuries are occasionally encountered and these are of varying nature and outcome. Methods: We reviewed 98 brain computed tomographic results retrospectively. These are cases that were done between Jan. 2013- Jan. 2014. Statistical ...

  11. Morphological Analysis of Bronchial Arteries and Variants with Computed Tomography Angiography

    Directory of Open Access Journals (Sweden)

    Claudia Nallely Esparza-Hernández

    2017-01-01

    Full Text Available The aim of our study was to determine the prevalence of anatomical variants of bronchial arteries using computed tomographic angiography in a population of northeastern Mexico. An observational, transversal, descriptive, comparative, retrospective study was performed using 139 imaging studies of Mexican patients in which we evaluated the following parameters from the left and right bronchial arteries: artery origin, branching pattern, arterial ostium, vertebral level of origin, diameter, and mediastinal trajectory. The anatomies of the bronchial arteries were similar in both genders, except distribution for vertebral origin level (p  0.006 and the diameter (p  0.013. Left and right arteries were similar, except for the mediastinal trajectory in reference to the esophagus (p<0.001 as well as the arterial diameter (p<0.001 and lumen diameter.

  12. MCPT: A Monte Carlo code for simulation of photon transport in tomographic scanners

    International Nuclear Information System (INIS)

    Prettyman, T.H.; Gardner, R.P.; Verghese, K.

    1990-01-01

    MCPT is a special-purpose Monte Carlo code designed to simulate photon transport in tomographic scanners. Variance reduction schemes and sampling games present in MCPT were selected to characterize features common to most tomographic scanners. Combined splitting and biasing (CSB) games are used to systematically sample important detection pathways. An efficient splitting game is used to tally particle energy deposition in detection zones. The pulse height distribution of each detector can be found by convolving the calculated energy deposition distribution with the detector's resolution function. A general geometric modelling package, HERMETOR, is used to describe the geometry of the tomographic scanners and provide MCPT information needed for particle tracking. MCPT's modelling capabilites are described and preliminary experimental validation is presented. (orig.)

  13. The robustness of two tomography reconstructing techniques with heavily noisy dynamical experimental data from a high speed gamma-ray tomograph

    International Nuclear Information System (INIS)

    Vasconcelos, Geovane Vitor; Melo, Silvio de Barros; Dantas, Carlos Costa; Moreira, Icaro Malta; Johansen, Geira; Maad, Rachid

    2013-01-01

    The PSIRT (Particle Systems Iterative Reconstructive Technique) is, just like the ART method, an iterative tomographic reconstruction technique with the recommended use in the reconstruction of catalytic density distribution in the refining process of oil in the FCC-type riser. The PSIRT is based upon computer graphics' particle systems, where the reconstructing material is initially represented as composed of particles subject to a force field emanating from the beams, whose intensities are parameterized by the differences between the experimental readings of a given beam trajectory, and the values corresponding to the current amount of particles landed in this trajectory. A dynamical process is set as the beams fields of attracting forces dispute the particles. At the end, with the equilibrium established, the particles are replaced by the corresponding regions of pixels. The High Speed Gamma-ray Tomograph is a 5-source-fan-beam device with a 17-detector deck per source, capable of producing up to a thousand complete sinograms per second. Around 70.000 experimental sinograms from this tomograph were produced simulating the move of gas bubbles in different angular speeds immersed in oil within the vessel, through the use of a two-hole-polypropylene phantom. The sinogram frames were set with several different detector integration times. This article studies and compares the robustness of both ART and PSIRT methods in this heavily noisy scenario, where this noise comes not only from limitations in the dynamical sampling, but also from to the underlying apparatus that produces the counting in the tomograph. These experiments suggest that PSIRT is a more robust method than ART for noisy data. Visual inspection on the resulting images suggests that PSIRT is a more robust method than ART for noisy data, since it almost never presents globally scattered noise. (author)

  14. Tomographic examination table

    International Nuclear Information System (INIS)

    Redington, R.W.; Henkes, J.L.

    1979-01-01

    Equipment is described for positioning and supporting patients during tomographic mammography using X-rays. The equipment consists of a table and fabric slings which permit the examination of a downward, pendant breast of a prone patient by allowing the breast to pass through a aperture in the table into a fluid filled container. The fluid has an X-ray absorption coefficient similar to that of soft human tissue allowing high density resolution radiography and permitting accurate detection of breast tumours. The shape of the equipment and the positioning of the patient allow the detector and X-ray source to rotate 360 0 about a vertical axis through the breast. This permits the use of relatively simple image reconstruction algorithms and a divergent X-ray geometry. (UK)

  15. Photon emission tomographic apparatus and method

    International Nuclear Information System (INIS)

    Blum, A.S.

    1983-01-01

    Tomographic imaging system employs large area, collimated scintillation detector rotated around radiation emitting subject. Detector support rotates with an inner ring inside a stationary outer ring. Counterbalanced detector support arm is forced by spring action to cause collimator face to follow body contour as detector rotates around the body, thereby reducing collimator to subject distance to improve system resolution. Includes adjustable subject support system

  16. Role of computed tomography in the integral diagnostic process of paranasal cavities tumors

    International Nuclear Information System (INIS)

    Lazarova, I.

    1990-01-01

    Results are reported of computed tomographic examination of 129 patients from 3 to 74 years of age, on clinical grounds suspected of having, or histologically verified, tumors of the paranasal cavities. Axial and/or coronary scanning (depending on the case) was performed on computed tomograph Tomoscan-310, according to previously selected programs. Computed tomography was evaluated with regard to the possibility for diagnosing tumors of the paranasal sinuses and its role in furnishing additional information in these diseases. The clearcut differentiation on the computed tomograms both of the bone structures and of the soft tissue - muscles, vessels, connective tissue and fatty tissue spaces - is emphasized. The clinical significance of this special X-ray method of examination in the preoperative period by demonstrating the different directions in which the tumors spread and the possibility for adequate planning of the radiotherapeutic field and posttherapeutic follow-up the pathologic process are pointed out. 5 figs., 5 refs

  17. An EGS4-ready tomographic computational model of a 14-year-old female torso for calculating organ doses from CT examinations

    International Nuclear Information System (INIS)

    Caon, M.; School of Physics and Electronic Systems Engineering, University of South Australia, The Levels Campus, Mawson Lakes, South Australia, 5095; Pattison, J.

    1999-01-01

    Fifty-four consecutive CT scans have been used to construct a tomographic computational model of a 14-year-old female torso suitable for the determination of organ doses from CT. The model, known as ADELAIDE, is in the form of an input file compatible with user codes based on XYZDOS.MOR from the readily available EGS4 Monte Carlo radiation transport code. ADELAIDE's dimensions are close to the Australian averages for her age so the model is representative of a 14-year-old girl. The realistic anatomy in the model differs considerably from that in Cristy's 15-year-old mathematical computational model by having realistically shaped organs that are appropriately located within a real external contour. Average absorbed dose to organs from simulated CT examinations of the chest and abdomen have been calculated for ADELAIDE using EGS4 within a geometry specific to the General Electric Hi-Speed Advantage CT scanner and using an x-ray spectrum calculated using data from the scanner's x-ray tube. The simulations include the scanner's beam shaping filter and patient table. It is suggested that the resulting values have fewer possible sources of uncertainty than organ doses derived from dose coefficients calculated for a MIRD style model with mathematical anatomy and a spectrum that may not match that of the scanner. The organ doses were normalized using the scanner's CTDI measured free-in-air and an EGS4 simulation of the CTDI measurement. Effective dose to the torso from 26-slice chest and 24-slice abdomen examinations (at 120 kV, 200 mAs, 7 mm slices) is 4.6±0.1mSv and 4.3±0.1mSv respectively. (author)

  18. Physics of x-ray computed tomography

    International Nuclear Information System (INIS)

    Akutagawa, W.M.; Huth, G.C.

    1976-01-01

    Sections are included on theoretical limits of x-ray computed tomography and the relationship of these limits to human organ imaging and specific disease diagnosis; potential of x-ray computed tomography in detection of small calcified particles in early breast cancer detection; early lung cancer measurement and detection; advanced materials for ionizing radiation detection; positron system with circular ring transaxial tomographic camera; contrast mechanism of transmission scanner and algorithms; and status of design on a 200 keV scanning proton microprobe

  19. Prospective Computed Tomographic Analysis of Osteochondral Lesions of the Ankle Joint Associated With Ankle Fractures.

    Science.gov (United States)

    Nosewicz, Tomasz L; Beerekamp, M Suzan H; De Muinck Keizer, Robert-Jan O; Schepers, Tim; Maas, Mario; Niek van Dijk, C; Goslings, J Carel

    2016-08-01

    Osteochondral lesions (OCLs) associated with ankle fracture correlate with unfavorable outcome. The goals of this study were to detect OCLs following ankle fracture, to associate fracture type to OCLs and to investigate whether OCLs affect clinical outcome. 100 ankle fractures requiring operative treatment were prospectively included (46 men, 54 women; mean age 44 ± 14 years, range 20-77). All ankle fractures (conventional radiography; 71 Weber B, 22 Weber C, 1 Weber A, 4 isolated medial malleolus and 2 isolated posterior malleolus fractures) were treated by open reduction and internal fixation. Multidetector computed tomography (CT) was performed postoperatively. For each OCL, the location, size, and Loomer OCL classification (CT modified Berndt and Harty classification) were determined. The subjective Foot and Ankle Outcome Scoring (FAOS) was used for clinical outcome at 1 year. OCLs were found in 10/100 ankle fractures (10.0%). All OCLs were solitary talar lesions. Four OCLs were located posteromedial, 4 posterolateral, 1 anterolateral, and 1 anteromedial. There were 2 type I OCLs (subchondral compression), 6 type II OCLs (partial, nondisplaced fracture) and 2 type IV OCLs (displaced fracture). Mean OCL size (largest diameter) was 4.4 ± 1.7 mm (range, 1.7 mm to 6.2 mm). Chi-square analysis showed no significant association between ankle fracture type and occurrence of OCLs. OCLs did occur only in Lauge-Hansen stage III/IV ankle fractures. There were no significant differences in FAOS outcome between patients with or without OCLs. Ten percent of investigated ankle fractures had associated OCLs on CT. Although no significant association between fracture type and OCL was found, OCLs only occurred in Lauge-Hansen stage III/IV ankle fractures. With the numbers available, OCLs did not significantly affect clinical outcome at 1 year according to FAOS. Level IV, observational study. © The Author(s) 2016.

  20. Industrial dynamic tomographic reconstruction; Reconstrucao tomografica dinamica industrial

    Energy Technology Data Exchange (ETDEWEB)

    Oliveira, Eric Ferreira de

    2016-07-01

    The state of the art methods applied to industrial processes is currently based on the principles of classical tomographic reconstructions developed for tomographic patterns of static distributions, or is limited to cases of low variability of the density distribution function of the tomographed object. Noise and motion artifacts are the main problems caused by a mismatch in the data from views acquired in different instants. All of these add to the known fact that using a limited amount of data can result in the presence of noise, artifacts and some inconsistencies with the distribution under study. One of the objectives of the present work is to discuss the difficulties that arise from implementing reconstruction algorithms in dynamic tomography that were originally developed for static distributions. Another objective is to propose solutions that aim at reducing a temporal type of information loss caused by employing regular acquisition systems to dynamic processes. With respect to dynamic image reconstruction it was conducted a comparison between different static reconstruction methods, like MART and FBP, when used for dynamic scenarios. This comparison was based on a MCNPx simulation as well as an analytical setup of an aluminum cylinder that moves along the section of a riser during the process of acquisition, and also based on cross section images from CFD techniques. As for the adaptation of current tomographic acquisition systems for dynamic processes, this work established a sequence of tomographic views in a just-in-time fashion for visualization purposes, a form of visually disposing density information as soon as it becomes amenable to image reconstruction. A third contribution was to take advantage of the triple color channel necessary to display colored images in most displays, so that, by appropriately scaling the acquired values of each view in the linear system of the reconstruction, it was possible to imprint a temporal trace into the regularly