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Sample records for underwent computed tomography

  1. Clinical and echocardiographic findings of patients with suspected acute pulmonary thromboembolism who underwent computed tomography pulmonary angiography

    Science.gov (United States)

    Adibi, Atoosa; Nouri, Shadi; Moradi, Maryam; Shahabi, Javad

    2016-01-01

    Background: The aim of the study was to determine the correlation between clinical and echocardiographic findings and risk factors of patients with suspected acute pulmonary thromboembolism (PTE) who underwent computed tomography pulmonary angiography (CTPA). Materials and Methods: In this cross-sectional study, 310 hospitalized patients aged >18 years with high clinical suspicion of PTE referred to imaging center of our hospital from different wards for CTPA were enrolled. The frequency of different clinical presentations, risk factors, items of Wells’ criteria, and echocardiographic findings was compared in patients with and without PTE, which have been diagnosed according to the CTPA results. Results: PTE was diagnosed in 53 (17.1%) of patients with suspected PTE. From clinical manifestations, tachypnea, pleuritic chest pain, and edema of lower extremities were significantly more frequent among patients with PTE (P < 0.05). Major surgery was the risk factor which was significantly more prevalent among patients with PTE (P < 0.05). Frequency of all criteria of Wells’ criteria, except hemoptysis, was significantly higher in patients with PTE (P < 0.05). The frequency of all studied echocardiographic variables was significantly higher in patients with PTE (P < 0.05). Conclusion: It is suggested that we could use the results of this study for utilizing the diagnostic process of PTE in patients with highly clinical suspicion of PTE and providing more validated decision. Using the results of this study, we could identify high-risk patients and made appropriate risk assessment for better management of patients with suspected PTE as well as reduce the rate of unnecessary CTPA and its related adverse consequences. PMID:28255326

  2. Clinical and echocardiographic findings of patients with suspected acute pulmonary thromboembolism who underwent computed tomography pulmonary angiography

    Directory of Open Access Journals (Sweden)

    Atoosa Adibi

    2016-01-01

    Full Text Available Background: The aim of the study was to determine the correlation between clinical and echocardiographic findings and risk factors of patients with suspected acute pulmonary thromboembolism (PTE who underwent computed tomography pulmonary angiography (CTPA. Materials and Methods: In this cross-sectional study, 310 hospitalized patients aged >18 years with high clinical suspicion of PTE referred to imaging center of our hospital from different wards for CTPA were enrolled. The frequency of different clinical presentations, risk factors, items of Wells' criteria, and echocardiographic findings was compared in patients with and without PTE, which have been diagnosed according to the CTPA results. Results: PTE was diagnosed in 53 (17.1% of patients with suspected PTE. From clinical manifestations, tachypnea, pleuritic chest pain, and edema of lower extremities were significantly more frequent among patients with PTE (P < 0.05. Major surgery was the risk factor which was significantly more prevalent among patients with PTE (P < 0.05. Frequency of all criteria of Wells' criteria, except hemoptysis, was significantly higher in patients with PTE (P < 0.05. The frequency of all studied echocardiographic variables was significantly higher in patients with PTE (P < 0.05. Conclusion: It is suggested that we could use the results of this study for utilizing the diagnostic process of PTE in patients with highly clinical suspicion of PTE and providing more validated decision. Using the results of this study, we could identify high-risk patients and made appropriate risk assessment for better management of patients with suspected PTE as well as reduce the rate of unnecessary CTPA and its related adverse consequences.

  3. Computed Tomography

    Science.gov (United States)

    Castellano, Isabel; Geleijns, Jacob

    After its clinical introduction in 1973, computed tomography developed from an x-ray modality for axial imaging in neuroradiology into a versatile three dimensional imaging modality for a wide range of applications in for example oncology, vascular radiology, cardiology, traumatology and even in interventional radiology. Computed tomography is applied for diagnosis, follow-up studies and screening of healthy subpopulations with specific risk factors. This chapter provides a general introduction in computed tomography, covering a short history of computed tomography, technology, image quality, dosimetry, room shielding, quality control and quality criteria.

  4. Computed Tomography (CT) -- Head

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    Full Text Available ... Professions Site Index A-Z Computed Tomography (CT) - Head Computed tomography (CT) of the head uses special ... the Head? What is CT Scanning of the Head? Computed tomography, more commonly known as a CT ...

  5. Computed Tomography (CT) -- Sinuses

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    Full Text Available ... Videos About Us News Physician Resources Professions Site Index A-Z Computed Tomography (CT) - Sinuses Computed tomography ( ... cross-sectional images generated during a CT scan can be reformatted in multiple planes, and can even ...

  6. Computed Tomography (CT) -- Sinuses

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    Full Text Available ... the Sinuses? What is CT (Computed Tomography) of the Sinuses? Computed tomography, more commonly known as a ... of page What are some common uses of the procedure? CT of the sinuses is primarily used ...

  7. Computed tomography

    International Nuclear Information System (INIS)

    Boyd, D.P.

    1989-01-01

    This paper reports on computed tomographic (CT) scanning which has improved computer-assisted imaging modalities for radiologic diagnosis. The advantage of this modality is its ability to image thin cross-sectional planes of the body, thus uncovering density information in three dimensions without tissue superposition problems. Because this enables vastly superior imaging of soft tissues in the brain and body, CT scanning was immediately successful and continues to grow in importance as improvements are made in speed, resolution, and cost efficiency. CT scanners are used for general purposes, and the more advanced machines are generally preferred in large hospitals, where volume and variety of usage justifies the cost. For imaging in the abdomen, a scanner with a rapid speed is preferred because peristalsis, involuntary motion of the diaphram, and even cardiac motion are present and can significantly degrade image quality. When contrast media is used in imaging to demonstrate scanner, immediate review of images, and multiformat hardcopy production. A second console is reserved for the radiologist to read images and perform the several types of image analysis that are available. Since CT images contain quantitative information in terms of density values and contours of organs, quantitation of volumes, areas, and masses is possible. This is accomplished with region-of- interest methods, which involve the electronic outlining of the selected region of the television display monitor with a trackball-controlled cursor. In addition, various image- processing options, such as edge enhancement (for viewing fine details of edges) or smoothing filters (for enhancing the detectability of low-contrast lesions) are useful tools

  8. Computed Tomography (CT) -- Head

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    Full Text Available ... Perfusion of the Head CT Angiography (CTA) Stroke Brain Tumors Computer Tomography (CT) Safety During Pregnancy Head and Neck Cancer X-ray, Interventional Radiology and Nuclear Medicine Radiation Safety Images related to Computed Tomography (CT) - Head Videos related to Computed Tomography ( ...

  9. Computed tomography for radiographers

    International Nuclear Information System (INIS)

    Brooker, M.

    1986-01-01

    Computed tomography is regarded by many as a complicated union of sophisticated x-ray equipment and computer technology. This book overcomes these complexities. The rigid technicalities of the machinery and the clinical aspects of computed tomography are discussed including the preparation of patients, both physically and mentally, for scanning. Furthermore, the author also explains how to set up and run a computed tomography department, including advice on how the room should be designed

  10. Computed Tomography (CT) -- Sinuses

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    Full Text Available ... are the limitations of CT of the Sinuses? What is CT (Computed Tomography) of the Sinuses? Computed ... nasal cavity by small openings. top of page What are some common uses of the procedure? CT ...

  11. Children's (Pediatric) CT (Computed Tomography)

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    Full Text Available ... News Physician Resources Professions Site Index A-Z Children's (Pediatric) CT (Computed Tomography) Pediatric computed tomography (CT) ... are the limitations of Children's CT? What is Children's CT? Computed tomography, more commonly known as a ...

  12. Computer tomography in otolaryngology

    Energy Technology Data Exchange (ETDEWEB)

    Gradzki, J. (Akademia Medyczna, Poznan (Poland))

    1981-01-01

    The principles of design and the action of computer tomography which was applied also for the diagnosis of nose, ear and throat diseases are discussed. Computer tomography makes possible visualization of the structures of the nose, nasal sinuses and facial skeleton in transverse and eoronal planes. The method enables an accurate evaluation of the position and size of neoplasms in these regions and differentiation of inflammatory exudates against malignant masses. In otology computer tomography is used particularly in the diagnosis of pontocerebellar angle tumours and otogenic brain abscesses. Computer tomography of the larynx and pharynx provides new diagnostic data owing to the possibility of obtaining transverse sections and visualization of cartilage. Computer tomograms of some cases are presented.

  13. Computed Tomography (CT) - Spine

    Science.gov (United States)

    ... the removal of fluid from a localized infection ( abscess ). In patients with narrowing ( stenosis ) of the spine ... Survey Images × Image Gallery Computed Tomography (CT or CAT scan) equipment View full size with caption Do ...

  14. Computed Tomography (CT) -- Head

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    Full Text Available ... the limitations of CT Scanning of the Head? What is CT Scanning of the Head? Computed tomography, ... than regular radiographs (x-rays). top of page What are some common uses of the procedure? CT ...

  15. Computed Tomography (CT) -- Sinuses

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    Full Text Available ... vessels. CT examinations are fast and simple; in emergency cases, they can reveal internal injuries and bleeding ... Neck Cancer X-ray, Interventional Radiology and Nuclear Medicine Radiation Safety Images related to Computed Tomography (CT) - ...

  16. Computed Tomography (CT) -- Head

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    Full Text Available ... of a stroke. a stroke, especially with a new technique called Perfusion CT. brain tumors. enlarged brain ... Neck Cancer X-ray, Interventional Radiology and Nuclear Medicine Radiation Safety Images related to Computed Tomography (CT) - ...

  17. Computed Tomography (CT) -- Head

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    Full Text Available ... for Brain Tumors Radiation Therapy for Head and Neck Cancer Others American Stroke Association National Stroke Association ... Computer Tomography (CT) Safety During Pregnancy Head and Neck Cancer X-ray, Interventional Radiology and Nuclear Medicine ...

  18. Computed Tomography (CT) -- Head

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    Full Text Available ... of the Head? What is CT Scanning of the Head? Computed tomography, more commonly known as a ... of page What are some common uses of the procedure? CT scanning of the head is typically ...

  19. Positron Emission Tomography - Computed Tomography (PET/CT)

    Science.gov (United States)

    ... News Physician Resources Professions Site Index A-Z Positron Emission Tomography - Computed Tomography (PET/CT) Positron emission tomography (PET) ... Emission TomographyComputed Tomography (PET/CT)? What is Positron Emission TomographyComputed Tomography (PET/CT) Scanning? Positron emission tomography, ...

  20. Computed Tomography (CT) -- Head

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    Full Text Available Toggle navigation Test/Treatment Patient Type Screening/Wellness Disease/Condition Safety En Español More Info Images/Videos About Us News Physician Resources Professions Site Index A-Z Computed Tomography (CT) - Head ...

  1. Computed Tomography (CT) -- Sinuses

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    Full Text Available Toggle navigation Test/Treatment Patient Type Screening/Wellness Disease/Condition Safety En Español More Info Images/Videos About Us News Physician Resources Professions Site Index A-Z Computed Tomography (CT) - Sinuses ...

  2. Computed Tomography (CT) -- Head

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    Full Text Available ... Computed tomography (CT) of the head uses special x-ray equipment to help assess head injuries, severe headaches, ... is a diagnostic medical test that, like traditional x-rays, produces multiple images or pictures of the inside ...

  3. Computed Tomography (CT) -- Sinuses

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    Full Text Available ... Computed tomography (CT) of the sinuses uses special x-ray equipment to evaluate the paranasal sinus cavities – hollow, ... is a diagnostic medical test that, like traditional x-rays, produces multiple images or pictures of the inside ...

  4. Computed tomography for radiographers

    International Nuclear Information System (INIS)

    Brooker, M.J.

    1986-01-01

    This book is directed towards giving radiographers an introduction to and basic knowledge of computerized tomography. The technical section discusses gantries and x-ray production, computer and disc drive image display, storage, artefacts quality assurance and design of departments. The clinical section includes patient preparation, radiotherapy planning, and interpretation of images from various areas of the anatomy. (U.K.)

  5. Computed tomography system

    International Nuclear Information System (INIS)

    Lambert, T.W.; Blake, J.E.

    1981-01-01

    This invention relates to computed tomography and is particularly concerned with determining the CT numbers of zones of interest in an image displayed on a cathode ray tube which zones lie in the so-called level or center of the gray scale window. (author)

  6. Quantitative cardiac computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Thelen, M.; Dueber, C.; Wolff, P.; Erbel, R.; Hoffmann, T.

    1985-06-01

    The scope and limitations of quantitative cardiac CT have been evaluated in a series of experimental and clinical studies. The left ventricular muscle mass was estimated by computed tomography in 19 dogs (using volumetric methods, measurements in two axes and planes and reference volume). There was good correlation with anatomical findings. The enddiastolic volume of the left ventricle was estimated in 22 patients with cardiomyopathies; using angiography as a reference, CT led to systematic under-estimation. It is also shown that ECG-triggered magnetic resonance tomography results in improved visualisation and may be expected to improve measurements of cardiac morphology.

  7. Children's (Pediatric) CT (Computed Tomography)

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    Full Text Available ... Physician Resources Professions Site Index A-Z Children's (Pediatric) CT (Computed Tomography) Pediatric computed tomography (CT) is ... a CT scan. View full size with caption Pediatric Content Some imaging tests and treatments have special ...

  8. Children's (Pediatric) CT (Computed Tomography)

    Science.gov (United States)

    ... Physician Resources Professions Site Index A-Z Children's (Pediatric) CT (Computed Tomography) Pediatric computed tomography (CT) is ... a CT scan. View full size with caption Pediatric Content Some imaging tests and treatments have special ...

  9. Gantry for computed tomography

    International Nuclear Information System (INIS)

    Kelman, A.L.

    1981-01-01

    A novel design of gantry for use in computed tomography is described in detail. In the new gantry, curved tracks are mounted to the laterally spaced apart sides of the frame which rotates and carries the detector and X-ray source. This permits the frame to be tilted either side of vertical enabling angular slices of body layers to be viewed and allows simplification of the algorithm which the computer uses for image reconstruction. The tracks are supported on rollers which carry the substantial weight. Explicit engineering details are presented. (U.K.)

  10. Gantry for computed tomography

    International Nuclear Information System (INIS)

    Kelman, A.L.; Peterson, T.E.

    1981-01-01

    A novel design of gantry for use in computed tomography is described in detail. In the new gantry, curved tracks are mounted to the laterally spaced apart sides of the frame which rotates and carries the detector and X-ray source. This permits the frame to be tilted either side of vertical enabling angular slices of body layers to be viewed and allows simplification of the algorithm which the computer uses for image reconstruction. The tracks are supported on rollers which carry the substantial weight. Explicit engineering details are presented especially of the ball bearing races used in the rotation. (U.K.)

  11. Multislice computed tomography coronary angiography

    NARCIS (Netherlands)

    F. Cademartiri (Filippo)

    2005-01-01

    markdownabstract__Abstract__ Computed Tomography (CT) imaging is also known as "CAT scanning" (Computed Axial Tomography). Tomography is from the Greek word "tomos" meaning "slice" or "section" and "graphia" meaning "describing". CT was invented in 1972 by British engineer Godfrey Hounsfield

  12. Computed tomography device

    International Nuclear Information System (INIS)

    Ohhashi, A.

    1985-01-01

    A computed tomography device comprising a subtraction unit which obtains differential data strings representing the difference between each time-serial projection data string of a group of projection data strings corresponding to a prospective reconstruction image generated by projection data strings acquired by a data acquisition system, a convolution unit which convolves each time-serial projection data string of the group of projection data strings corresponding to the prospective reconstruction image, and a back-projection unit which back-projects the convolved data strings

  13. Computed Tomography Study Of Complicated Bacterial Meningitis ...

    African Journals Online (AJOL)

    To monitor the structural intracranial complications of bacterial meningitis using computed tomography (CT) scan. Retrospective study of medical and radiological records of patients who underwent CT scan over a 4 year period. AUniversityTeachingHospital in a developing country. Thirty three patients with clinically and ...

  14. Mesenteric panniculitis: computed tomography aspects

    International Nuclear Information System (INIS)

    Moreira, Luiza Beatriz Melo; Alves, Jose Ricardo Duarte; Marchiori, Edson; Pinheiro, Ricardo Andrade; Melo, Alessandro Severo Alves de; Noro, Fabio

    2001-01-01

    Mesenteric panniculitis is an inflammatory process that represents the second stage of a rare progressive disease involving the adipose tissue of the mesentery. Imaging methods used in the diagnosis of mesenteric panniculitis include barium studies, ultrasonography, computed tomography and magnetic resonance imaging. Computed tomography is important for both, diagnosis and evaluation of the extension of the disease and treatment monitoring. Computed tomography findings may vary according to the stage of the disease and the amount of inflammatory material or fibrosis. There is also good correlation between the computed tomography and anatomical pathology findings. The authors studied 10 patients with mesenteric panniculitis submitted to computed tomography. Magnetic resonance imaging was also performed in one patient. In all patients, computed tomography revealed a heterogeneous mass in the mesentery with density of fat, interspersed with areas of soft tissue density and dilated vessels. (author)

  15. Gantry for computed tomography

    International Nuclear Information System (INIS)

    Kelman, A.L.; O'Dell, W.R.; Brook, R.F.; Hein, P.W.; Brandt, R.T.

    1981-01-01

    A novel design of gantry for use in computed tomography is described in detail. In the new gantry, curved tracks are mounted to the laterally spaced apart sides of the frame which rotates and carries the detector and X-ray source. This permits the frame to be tilted either side of vertical enabling angular slices of body layers to be viewed and allows simplification of the algorithm which the computer uses for image reconstruction. A failsafe, solenoid brake is described which can lock the shaft against rotation. The gantry also contains a hoist mechanism which aids maintenance of the heavy X-ray tube and/or detector arrays. Explicit engineering details are presented. (U.K.)

  16. Positron emission computed tomography

    International Nuclear Information System (INIS)

    Grover, M.; Schelbert, H.R.

    1985-01-01

    Regional mycardial blood flow and substrate metabolism can be non-invasively evaluated and quantified with positron emission computed tomography (Positron-CT). Tracers of exogenous glucose utilization and fatty acid metabolism are available and have been extensively tested. Specific tracer kinetic models have been developed or are being tested so that glucose and fatty acid metabolism can be measured quantitatively by Positron-CT. Tracers of amino acid and oxygen metabolism are utilized in Positron-CT studies of the brain and development of such tracers for cardiac studies are in progress. Methods to quantify regional myocardial blood flow are also being developed. Previous studies have demonstrated the ability of Positron-/CT to document myocardial infarction. Experimental and clinical studies have begun to identify metabolic markers of reversibly ischemic myocardium. The potential of Positron-CT to reliably detect potentially salvageable myocardium and, hence, to identify appropriate therapeutic interventions is one of the most exciting applications of the technique

  17. Proton computed tomography

    International Nuclear Information System (INIS)

    Hanson, K.M.

    1978-01-01

    The use of protons or other heavy charged particles instead of x rays in computed tomography (CT) is explored. The results of an experimental implementation of proton CT are presented. High quality CT reconstructions are obtained at an average dose reduction factor compared with an EMI 5005 x-ray scanner of 10:1 for a 30-cm-diameter phantom and 3.5:1 for a 20-cm diameter. The spatial resolution is limited by multiple Coulomb scattering to about 3.7 mm FWHM. Further studies are planned in which proton and x-ray images of fresh human specimens will be compared. Design considerations indicate that a clinically useful proton CT scanner is eminently feasible

  18. Computed tomography of choledocholithiasis

    Energy Technology Data Exchange (ETDEWEB)

    Jeffrey, R.B.; Federle, M.P.; Laing, F.C.; Wall, S.; Rego, J.; Moss, A.A.

    1983-06-01

    Computed tomography (CT) correctly diagnosed common bile duct stones in 19 (90%) of 21 surgically proven cases. CT demonstrated calculi in all 13 patients with calcium bilirubinate common duct stones and six of eight patients with predominantly cholesterol stones. There were two false-negative diagnoses in patients with cholesterol calculi scanned at 1 cm intervals. Cholesterol stones are nearly isodense with bile and may be difficult to visualize in the common duct by routine scanning techniques. There are three suggestive CT features of cholesterol common duct calculi: (1) abrupt termination of the distal common bile duct without an obstructing mass, (2) a faint rim of increased density along the peripheral margin of a low-density calculus, and (3) mottled areas of increased density centrally within a calculus elevating its CT number above values for normal bile. Modification of scanning technique to obtain high-resolution images of the extrahepatic biliary tree is stressed to optimize visualization of the above findings.

  19. Computed tomography apparatus

    International Nuclear Information System (INIS)

    Palermo, A.; Zupancic, A.

    1981-01-01

    A computed tomography (CT) scanner apparatus including improved arrangement for transferring high voltage electrical energy between a stationary gantry and a rotating assembly is described. The assembly carries the X-ray source and has an opening defining an aperture to receive a part of a patient. A first axis about which the assembly rotates, passes through the aperture. The apparatus includes a number of slip rings which are used for effecting the transfer of the electrical energy. Respective portions of the gantry and rotating assembly define a cavity which contains an insulating di-electric fluid in which the slip rings are immersed. The apparatus is of compact design and, further, the rotating assembly and the slip rings can be tilted about a second axis which intersects the first axis. (author)

  20. Computed tomography intravenous cholangiography

    International Nuclear Information System (INIS)

    Nascimento, S.; Murray, W.; Wilson, P.

    1997-01-01

    Indications for direct visualization of the bile ducts include bile duct dilatation demonstrated by ultrasound or computed tomography (CT) scanning, where the cause of the bile duct dilatation is uncertain or where the anatomy of bile duct obstruction needs further clarification. Another indication is right upper quadrant pain, particularly in a post-cholecystectomy patient, where choledocholithiasis is suspected. A possible new indication is pre-operative evaluation prior to laparoscopic cholecystectomy. The bile ducts are usually studied by endoscopic retrograde cholangiopancreatography (ERCP), or, less commonly, trans-hepatic cholangiography. The old technique of intravenous cholangiography has fallen into disrepute because of inconsistent bile-duct opacification. The advent of spiral CT scanning has renewed interest in intravenous cholangiography. The CT technique is very sensitive to the contrast agent in the bile ducts, and angiographic and three-dimensional reconstructions of the biliary tree can readily be obtained using the CT intravenous cholangiogram technique (CT IVC). Seven patients have been studied using this CT IVC technique, between February 1995 and June 1996, and are the subject of the present report. Eight further studies have since been performed. The results suggest that CT IVC could replace ERCP as the primary means of direct cholangiography, where pancreatic duct visualization is not required. (authors)

  1. Computed tomography intravenous cholangiography

    Energy Technology Data Exchange (ETDEWEB)

    Nascimento, S.; Murray, W.; Wilson, P. [Pittwater Radiology, Dee Why, NSW, (Australia)

    1997-08-01

    Indications for direct visualization of the bile ducts include bile duct dilatation demonstrated by ultrasound or computed tomography (CT) scanning, where the cause of the bile duct dilatation is uncertain or where the anatomy of bile duct obstruction needs further clarification. Another indication is right upper quadrant pain, particularly in a post-cholecystectomy patient, where choledocholithiasis is suspected. A possible new indication is pre-operative evaluation prior to laparoscopic cholecystectomy. The bile ducts are usually studied by endoscopic retrograde cholangiopancreatography (ERCP), or, less commonly, trans-hepatic cholangiography. The old technique of intravenous cholangiography has fallen into disrepute because of inconsistent bile-duct opacification. The advent of spiral CT scanning has renewed interest in intravenous cholangiography. The CT technique is very sensitive to the contrast agent in the bile ducts, and angiographic and three-dimensional reconstructions of the biliary tree can readily be obtained using the CT intravenous cholangiogram technique (CT IVC). Seven patients have been studied using this CT IVC technique, between February 1995 and June 1996, and are the subject of the present report. Eight further studies have since been performed. The results suggest that CT IVC could replace ERCP as the primary means of direct cholangiography, where pancreatic duct visualization is not required. (authors). 11 refs., 6 figs.

  2. Intraoperative computed tomography.

    Science.gov (United States)

    Tonn, J C; Schichor, C; Schnell, O; Zausinger, S; Uhl, E; Morhard, D; Reiser, M

    2011-01-01

    Intraoperative computed tomography (iCT) has gained increasing impact among modern neurosurgical techniques. Multislice CT with a sliding gantry in the OR provides excellent diagnostic image quality in the visualization of vascular lesions as well as bony structures including skull base and spine. Due to short acquisition times and a high spatial and temporal resolution, various modalities such as iCT-angiography, iCT-cerebral perfusion and the integration of intraoperative navigation with automatic re-registration after scanning can be performed. This allows a variety of applications, e.g. intraoperative angiography, intraoperative cerebral perfusion studies, update of cerebral and spinal navigation, stereotactic procedures as well as resection control in tumour surgery. Its versatility promotes its use in a multidisciplinary setting. Radiation exposure is comparable to standard CT systems outside the OR. For neurosurgical purposes, however, new hardware components (e.g. a radiolucent headholder system) had to be developed. Having a different range of applications compared to intraoperative MRI, it is an attractive modality for intraoperative imaging being comparatively easy to install and cost efficient.

  3. Optical Coherence Tomography Parameters in Morbidly Obese Patients Who Underwent Laparoscopic Sleeve Gastrectomy

    Directory of Open Access Journals (Sweden)

    Berna Dogan

    2016-01-01

    Full Text Available Purpose. To investigate changes in optical coherence tomography parameters in morbidly obese patients who had undergone laparoscopic sleeve gastrectomy (LSG. Methods. A total of 41 eyes of 41 morbidly obese patients (BMI ≥ 40 who had undergone LSG were included in study. The topographic optic disc parameters, central macular thickness (CMT, total macular volume (TMV, and retinal ganglion cell layer (RGCL were measured by spectral-domain optical coherence tomography (SD-OCT. Subfoveal choroidal thickness (SFCT was measured by enhanced deep imaging-optical coherence tomography (EDI-OCT. Results. The mean CMT was 237.4±24.5 μm, 239.3±24.1 μm, and 240.4±24.5 μm preoperatively, 3 months postoperatively, and 6 months postoperatively, respectively (p<0.01. The mean TMV was 9.88±0.52 mm3, 9.96±0.56 mm3, and 9.99±0.56 mm3 preoperatively, 3 months postoperatively, and 6 months postoperatively, respectively (p<0.01. The mean RGCL was 81.2±6.5 μm, 82.7±6.6 μm, and 82.9±6.5 μm preoperatively, 3 months postoperatively, and 6 months postoperatively, respectively (p<0.01. The mean SFCT was 309.8±71.8 μm, 331.0±81.4 μm, and 352.7±81.4 μm preoperatively, 3 months postoperatively, and 6 months postoperatively, respectively (p<0.01. No statistically significant differences were found between the preoperative values and 3- and 6-month postoperative values in rim area (p=0.34, disc area (p=0.64, vertical cup/disc ratio (p=0.39, cup volume (p=0.08, or retinal nerve fiber layer (p=0.90. Conclusions. Morbidly obese patients who undergo LSG experience a statistically significant increase in CMT, TMV, SFCT, and RGCL at 3 months and 6 months after surgery.

  4. Odontoid Fracture: Computed Tomography

    Directory of Open Access Journals (Sweden)

    Jonathan Peña

    2016-09-01

    Full Text Available History of present illness: An 84-year-old male presented with left-sided posterior head, neck, and back pain after a ground level fall. Exam was notable for left parietal scalp laceration and midline cervical spine tenderness with no obvious deformities. He was neurovascularly intact, and placed in an Aspen Collar with strict spine precautions. Significant findings: Computed Tomography (CT of the cervical spine showed a stable, acute, non-displaced fracture of the odontoid process extending into the body of C2, consistent with a Type III Odontoid Fracture. He was evaluated by orthopedic spine service who recommended conservative, non-operative management. Discussion: The cervical spine is composed of seven vertebrae, with C1 and C2 commonly referred to as the Atlas and Axis, respectively. Unique to C2 is a bony prominence, the Odontoid Process (Dens. Hyperextension or hyperflexion injuries can induce significant stress causing fractures. Odontoid fractures comprise approximately 10% of vertebral fractures, and there are three types with varying stability.1 Type 1 is the rarest and is a fracture involving the superior segment of the Dens. It is considered a stable fracture. Type 2 is the most common and is a fracture involving the base of the odontoid process, below the transverse component of the cruciform ligament. This fracture is unstable and requires operative stabilization. 2 Type 3 odontoid fractures are classified by a fracture of the Odontoid process, as well as the lateral masses of the C2. Determining the stability of a Type III Odontoid fracture requires radiographic evaluation. Strict cervical spine precautions must be adhered to until adequate imaging and surgical consultation is obtained. CT of the of cervical spine fractures poses several advantages to plain film radiography due to the ability to view the anatomy in three planes. 3 However, if there is concern for ligamentous injury, MRI is the preferred modality.3

  5. Children's (Pediatric) CT (Computed Tomography)

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    Full Text Available ... Children's (Pediatric) CT (Computed Tomography) Sponsored by Please note RadiologyInfo.org is not a medical facility. Please ... is further reviewed by committees from the American College of Radiology (ACR) and the Radiological Society of ...

  6. Children's (Pediatric) CT (Computed Tomography)

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    Full Text Available ... Videos About Us News Physician Resources Professions Site Index A-Z Children's (Pediatric) CT (Computed Tomography) Pediatric ... cross-sectional images generated during a CT scan can be reformatted in multiple planes, and can even ...

  7. Children's (Pediatric) CT (Computed Tomography)

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    Full Text Available ... risks? What are the limitations of Children's CT? What is Children's CT? Computed tomography, more commonly known ... newborns, infants and older children. top of page What are some common uses of the procedure? CT ...

  8. Children's (Pediatric) CT (Computed Tomography)

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    Full Text Available ... Pediatric computed tomography (CT) is a fast, painless exam that uses special x-ray equipment to create ... your doctor and the technologist prior to the exam if your child has a known allergy to ...

  9. Children's (Pediatric) CT (Computed Tomography)

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    Full Text Available ... considerations. The teddy bear denotes child-specific content. Related Articles and Media Radiation Dose in X-Ray ... Materials Anesthesia Safety Children and Radiation Safety Images related to Children's (Pediatric) CT (Computed Tomography) Videos related ...

  10. Computed tomography of the chest

    International Nuclear Information System (INIS)

    Norsworthy, R.

    1984-01-01

    Computed tomography of the chest can be useful in gaining detailed information of lung and mediastinal pathology, and in following up lesions during and after treatment. Considerations for dynamic and standard techniques are presented

  11. Computed Tomography (CT) -- Sinuses

    Medline Plus

    Full Text Available ... tomography, more commonly known as a CT or CAT scan, is a diagnostic medical test that, like ... imaging provides real-time imaging, making it a good tool for guiding minimally invasive procedures such as ...

  12. Computed Tomography (CT) -- Sinuses

    Medline Plus

    Full Text Available ... tomography (CT) scan. View full size with caption Pediatric Content Some imaging tests and treatments have special pediatric considerations. The teddy bear denotes child-specific content. ...

  13. Computed Tomography (CT) -- Head

    Medline Plus

    Full Text Available ... tomography (CT) scan. View full size with caption Pediatric Content Some imaging tests and treatments have special pediatric considerations. The teddy bear denotes child-specific content. ...

  14. Computed Tomography (CT) -- Head

    Medline Plus

    Full Text Available ... images. These images can be viewed on a computer monitor, printed on film or transferred to a ... other in a ring, called a gantry. The computer workstation that processes the imaging information is located ...

  15. Computed Tomography (CT) -- Sinuses

    Medline Plus

    Full Text Available ... images. These images can be viewed on a computer monitor, printed on film or transferred to a ... other in a ring, called a gantry. The computer workstation that processes the imaging information is located ...

  16. Computed Tomography (CT) -- Head

    Medline Plus

    Full Text Available ... ring, called a gantry. The computer workstation that processes the imaging information is located in a separate ... follows a spiral path. A special computer program processes this large volume of data to create two- ...

  17. Computed Tomography (CT) -- Sinuses

    Medline Plus

    Full Text Available ... ring, called a gantry. The computer workstation that processes the imaging information is located in a separate ... follows a spiral path. A special computer program processes this large volume of data to create two- ...

  18. Pulmonary amyloidosis: computed tomography findings

    International Nuclear Information System (INIS)

    Marchiori, Edson; Ferreira, Angela; Crespo, Sheila Jandira Vianna

    2003-01-01

    We report the computed tomography findings of five patients with pathology proven pulmonary amyloidosis. Tracheobronchial amyloidosis with calcified nodules and plaques in the tracheal wall were seen in two patients. Two other patients had diffuse parenchymal disease with calcified lesions, one had reticular and nodular sub pleural opacities whereas the other had nodular interlobular septal thickening and a parenchymal consolidation. The latter presented the nodular type of the disease with multiple sharp nodules scattered throughout the lungs and interspersed calcifications. The computed tomography findings observed were not specific but strongly suggestive of amyloidosis. (author)

  19. Computed tomography of chest wall abscess

    International Nuclear Information System (INIS)

    Ikezoe, Junpei; Morimoto, Shizuo; Akira, Masanori

    1986-01-01

    Inflammatory lesions of the chest wall become less common because of the improvement of antibiotics and chemotherapeutic agents. Over a 5-year period, 7 patients with chest wall inflammatory diseases underwent chest computed tomography. These were 2 tuberculous pericostal abscesses, 2 empyema necessitatis, 1 spinal caries, and 2 bacterial chest wall abscesses (unknown organisms). Computed tomography (CT) helped in demonstrating the density, border, site, and extent of the lesions. CT images also demonstrated the accompaning abnormalities which included bone changes, pleural calcification, or old tuberculous changes of the lung. CT was very effective to demonstrate the communicating portions from the inside of the bony thorax to the outside of the bony thorax in 2 empyema necessitatis. (author)

  20. Emission computed tomography

    International Nuclear Information System (INIS)

    Phelps, M.E.

    1977-01-01

    Although there are many common aspects to x-ray transmission and radionuclide emission (ECT) computerized tomography, there are added difficulties and a number of particular factors which form the basis of ECT. The relationship between the physical factors, system design, methodologic approach and assumptions of ECT is discussed. The instrumentation design and application strategies in ECT at this time are diverse and in a rapid stage of development. The approaches are divided into two major categories of Single Photon Counting (SPC) employing scanner and camera concepts with radionuclides of 99 /sup m/Tc, 201 Tl, 123 I etc., and Annihilation Coincidence Detection (ACD) of positron-emitting radionuclides. Six systems in the former and ten systems in the latter category, with examples of typical studies, illustrate the different approaches

  1. Computed Tomography (CT) -- Head

    Medline Plus

    Full Text Available ... be viewed on a computer monitor, printed on film or transferred to a CD or DVD. CT ... distinguished from one another on an x-ray film or CT electronic image. In a conventional x- ...

  2. Computed Tomography (CT) -- Sinuses

    Medline Plus

    Full Text Available ... be viewed on a computer monitor, printed on film or transferred to a CD or DVD. CT ... distinguished from one another on an x-ray film or CT electronic image. In a conventional x- ...

  3. Computed Tomography (CT) -- Sinuses

    Medline Plus

    Full Text Available ... computer software, the result is a very detailed multidimensional view of the body's interior. Refinements in detector ... community, you can search the ACR-accredited facilities database . This website does not provide cost information. The ...

  4. Computed Tomography (CT) -- Head

    Medline Plus

    Full Text Available ... computer software, the result is a very detailed multidimensional view of the body's interior. Refinements in detector ... community, you can search the ACR-accredited facilities database . This website does not provide cost information. The ...

  5. Computed Tomography (CT) -- Sinuses

    Medline Plus

    Full Text Available ... diagnose sinusitis . evaluate sinuses that are filled with fluid or thickened sinus membranes . detect the presence of ... other in a ring, called a gantry. The computer workstation that processes the imaging information is located ...

  6. Computed Tomography (CT) -- Sinuses

    Medline Plus

    Full Text Available ... openings. top of page What are some common uses of the procedure? CT of the sinuses is ... special computer program processes this large volume of data to create two-dimensional cross-sectional images of ...

  7. Computed Tomography (CT) -- Head

    Medline Plus

    Full Text Available ... rays). top of page What are some common uses of the procedure? CT scanning of the head ... special computer program processes this large volume of data to create two-dimensional cross-sectional images of ...

  8. Computed Tomography (CT) -- Sinuses

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    Full Text Available ... beam follows a spiral path. A special computer program processes this large volume of data to create ... technologist or nurse, under the direction of a physician, may offer you some medication to help you ...

  9. Computed Tomography (CT) -- Sinuses

    Medline Plus

    Full Text Available ... slices. When the image slices are reassembled by computer software, the result is a very detailed multidimensional view of the body's interior. Refinements in detector technology allow nearly all CT scanners to obtain multiple ...

  10. Computed Tomography (CT) -- Head

    Medline Plus

    Full Text Available ... slices. When the image slices are reassembled by computer software, the result is a very detailed multidimensional view of the body's interior. Refinements in detector technology allow nearly all CT scanners to obtain multiple ...

  11. Computed Tomography (CT) -- Head

    Medline Plus

    Full Text Available ... When the image slices are reassembled by computer software, the result is a very detailed multidimensional view ... If contrast material is used, depending on the type of exam, it will be swallowed, injected through ...

  12. Computed Tomography (CT) -- Sinuses

    Medline Plus

    Full Text Available ... When the image slices are reassembled by computer software, the result is a very detailed multidimensional view ... actual CT scanning is performed. Depending on the type of CT scan, the machine may make several ...

  13. Computed Tomography (CT) -- Head

    Medline Plus

    Full Text Available ... other medical conditions and whether you have a history of heart disease, asthma, diabetes, kidney disease or ... other in a ring, called a gantry. The computer workstation that processes the imaging information is located ...

  14. Computed Tomography (CT) -- Sinuses

    Medline Plus

    Full Text Available ... other medical conditions and whether you have a history of heart disease, asthma, diabetes, kidney disease or ... other in a ring, called a gantry. The computer workstation that processes the imaging information is located ...

  15. Computed Tomography (CT) -- Sinuses

    Medline Plus

    Full Text Available ... special computer program processes this large volume of data to create two-dimensional cross-sectional images of ... Society of Urogenital Radiology note that the available data suggest that it is safe to continue breastfeeding ...

  16. Computed Tomography (CT) -- Head

    Medline Plus

    Full Text Available ... special computer program processes this large volume of data to create two-dimensional cross-sectional images of ... Society of Urogenital Radiology note that the available data suggest that it is safe to continue breastfeeding ...

  17. Computed Tomography (CT) -- Sinuses

    Medline Plus

    Full Text Available ... When the image slices are reassembled by computer software, the result is a very detailed multidimensional view ... accurate. A major advantage of CT is its ability to image bone, soft tissue and blood vessels ...

  18. Computed Tomography (CT) -- Head

    Medline Plus

    Full Text Available ... When the image slices are reassembled by computer software, the result is a very detailed multidimensional view ... accurate. A major advantage of CT is its ability to image bone, soft tissue and blood vessels ...

  19. Computed Tomography (CT) -- Head

    Medline Plus

    Full Text Available ... When the image slices are reassembled by computer software, the result is a very detailed multidimensional view ... full size with caption Pediatric Content Some imaging tests and treatments have special pediatric considerations. The teddy ...

  20. Computed Tomography (CT) -- Sinuses

    Medline Plus

    Full Text Available ... When the image slices are reassembled by computer software, the result is a very detailed multidimensional view ... of the Sinuses? CT is usually the first test ordered when a sinus tumor is suspected. If ...

  1. Computed Tomography (CT) -- Sinuses

    Medline Plus

    Full Text Available ... When the image slices are reassembled by computer software, the result is a very detailed multidimensional view ... artifacts on the images. This loss of image quality can resemble the blurring seen on a photograph ...

  2. Computed Tomography (CT) -- Head

    Medline Plus

    Full Text Available ... When the image slices are reassembled by computer software, the result is a very detailed multidimensional view ... cause blurring of the images and degrade the quality of the examination the same way that it ...

  3. Computed tomography:the details.

    Energy Technology Data Exchange (ETDEWEB)

    Doerry, Armin Walter

    2007-07-01

    Computed Tomography (CT) is a well established technique, particularly in medical imaging, but also applied in Synthetic Aperture Radar (SAR) imaging. Basic CT imaging via back-projection is treated in many texts, but often with insufficient detail to appreciate subtleties such as the role of non-uniform sampling densities. Herein are given some details often neglected in many texts.

  4. Laryngopyocele: signs on computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Nazaroglu, Hasan E-mail: hnazarog@dicle.edu.tr; Oezates, Mustafa; Uyar, Asur; Deger, Emin; Simsek, Masum

    2000-01-01

    A laryngocele is an air-filled dilation of the saccule of the larynx. An infected laryngocele is called a laryngopyocele. Our experience with a case of laryngopyocele with signs on computed tomography before and after antibiotic therapy is presented since laryngopyocele is more unusual.

  5. Laryngopyocele: signs on computed tomography

    International Nuclear Information System (INIS)

    Nazaroglu, Hasan; Oezates, Mustafa; Uyar, Asur; Deger, Emin; Simsek, Masum

    2000-01-01

    A laryngocele is an air-filled dilation of the saccule of the larynx. An infected laryngocele is called a laryngopyocele. Our experience with a case of laryngopyocele with signs on computed tomography before and after antibiotic therapy is presented since laryngopyocele is more unusual

  6. Computer tomography in Caisson's disease

    International Nuclear Information System (INIS)

    Horvath, F.; Csobaly, S.; Institute for Advanced Training of Physicians, Budapest

    1981-01-01

    Computer tomography was performed on 20 patients with the early stages of Caisson osteoarthropathy, as well as in other patients with chronic bone infarcts. From their results the authors have formed the opinion that CT is valuable, not only in the diagnosis of early cases, but that it can provide significant information concerning the osteopathy and bone infarcts. (orig.) [de

  7. Computed Tomography (CT) -- Head

    Medline Plus

    Full Text Available ... electronic x-ray detectors are located opposite each other in a ring, called a gantry. The computer workstation that processes the imaging information is located in a separate control room, where the technologist operates the scanner and ...

  8. Computed Tomography (CT) -- Sinuses

    Medline Plus

    Full Text Available ... electronic x-ray detectors are located opposite each other in a ring, called a gantry. The computer workstation that processes the imaging information is located in a separate control room, where the technologist operates the scanner and ...

  9. Integrated positron emission tomography/computed tomography for ...

    African Journals Online (AJOL)

    Integrated positron emission tomography/computed tomography for evaluation of mediastinal lymph node staging of non-small-cell lung cancer in a tuberculosisendemic area: A 5-year prospective observational study.

  10. Cranial computed tomography in psychiatry

    International Nuclear Information System (INIS)

    Falkai, P.; Bogerts, B.

    1993-01-01

    Computed tomography has gained importance as a diagnostic tool in psychiatry to exclude structural brain pathology, but has passed on its role in research to magnetic resonance tomography. It helps to distinguish between senile dementia of Alzheimer type and multi-infarct dementia. The enlargement of the ventricular system and cortical sulci is well established in schizophrenic and affective psychosis. Some alcohol addicts show a considerable degree of cerebral atrophy, only exceeded by demented patients, but this condition is potentially reversible. To screen psychiatric patients by CT is recommendable, as 2-10% of hospitalized psychiatric patients have structural brain disease. (orig.) [de

  11. Duodenal diverticulitis. computed tomography findings

    International Nuclear Information System (INIS)

    Sanchez, E.; Martin, S.; Garcia, J.; Dominguez, A.

    2001-01-01

    Duodenal diverticular occur very frequently among the general public. However, duodenal diverticulitis is a very uncommon clinical entity, the diagnosis of which requires radiological studies since the clinical signs cam mimic a great number of disease processes with different treatments. We present a case of duodenal diverticulitis in which the diagnosis according to ultrasound and computed tomography (CT) studies was confirmed intraoperatively. We also review the few cases of this entity reported in the literature. The CT findings are highly suggestive of duodenal diverticulitis given their similarity to those associated with diverticulitis at other sites. (Author) 5 refs,

  12. Computed tomography of stress fracture

    International Nuclear Information System (INIS)

    Murcia, M.; Brennan, R.E.; Edeiken, J.

    1982-01-01

    An athletic young female developed gradual onset of pain in the right leg. Plain radiographs demonstrated solid periosteal reaction in the tibia compatible with stress fracture. She stopped sport activites but her pain continued. Follow-up radiographs of the tibia revealed changes suspicious for osteoid osteoma. Computed tomography (CT) scan demonstrated periosteal reaction, but in addition, lucent fracture lines in the tibial cortex were evident. CT obviated the need for more invasive diagnostic procedures in this patient. In selected cases CT may be useful to confirm the diagnosis of stress fracture when plain radiographic or routine tomographic studies are not diagnostic. (orig.)

  13. High speed computer assisted tomography

    International Nuclear Information System (INIS)

    Maydan, D.; Shepp, L.A.

    1980-01-01

    X-ray generation and detection apparatus for use in a computer assisted tomography system which permits relatively high speed scanning. A large x-ray tube having a circular anode (3) surrounds the patient area. A movable electron gun (8) orbits adjacent to the anode. The anode directs into the patient area xrays which are delimited into a fan beam by a pair of collimating rings (21). After passing through the patient, x-rays are detected by an array (22) of movable detectors. Detector subarrays (23) are synchronously movable out of the x-ray plane to permit the passage of the fan beam

  14. High speed computer assisted tomography

    International Nuclear Information System (INIS)

    Maydan, D.; Shepp, L.A.

    1980-01-01

    X-ray generation and detection apparatus for use in a computer assisted tomography system which permits relatively high speed scanning. A large X-ray tube having an annular anode surrounds the patient area. A movable electron gun orbits adjacent to the anode. The anode directs X-rays through the patient area towards an array of movable detectors. Detector subarrays are synchronously movable out of the X-ray plane to permit passage of the X-ray beam as it rotates within a plane in which the detector array is disposed. (author)

  15. Brain metastases: computed tomography assessment

    International Nuclear Information System (INIS)

    Gordillo, Victoria; Yagual, Glenda; Vinueza, Clayreth

    1998-01-01

    Intracranial metastatic tumor is relatively frequent in patients with cancer from other origin. Its location and type of metastasis varies in relation to its linage from the primary tumor. And the sequence goes from the most frequent: lung and breast cancer, melanoma, GU tract, leukemia, GI tract, head and neck tumor. Computed tomography findings are extremely varied and non specific, so there are no radiologic characteristics even from the primary tumor. We reviewed 29 TC studies in the Radiology department of ION-SOLCA, from patients with diagnosis of brain metastasis, our findings showed the great variability in the radio-diagnosis imaging. (The author)

  16. Computed Tomography in Forensic Medicine

    DEFF Research Database (Denmark)

    Leth, Peter Mygind

    2015-01-01

    Modern diagnostic imagining techniques are gaining popularity in forensic medicine. Denmark has been involved in the development of this use of imaging techniques from the beginning. The Institute of Forensic Medicine at the University of Southern Denmark acquired a helical computed tomography (CT...... AND METHODS: This thesis investigated 900 forensic cases that were CT-scanned and autopsied at the Institute of Forensic Medicine, University of Southern Denmark, from 2006-2011. The scanner was a Siemens Somatom Spirit dual-slice CT-scanner with a Siemens Syngo MultiModality workstation. Contrast enhancement...

  17. Computed Tomography of Patients with Head Trauma following ...

    African Journals Online (AJOL)

    METHODS: Retrospective analysis of cranial computed tomography (CT) films, request cards, duplicate copy of radiology reports, soft copy CT images and case notes of 61 patients who underwent cranial CT scan on account of road traffic accidents. The study CT scans were performed at the radiology department of ...

  18. 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%.

  19. Adaptive Computed Tomography Imaging Spectrometer Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The present proposal describes the development of an adaptive Computed Tomography Imaging Spectrometer (CTIS), or "Snapshot" spectrometer which can "instantaneously"...

  20. Computed tomography findings of malignant pleural mesothelioma

    Energy Technology Data Exchange (ETDEWEB)

    Shiota, Yutaro; Sato, Toshio; Yamaguchi, Kazuo; Ono, Tetsuya; Kaji, Masaro; Niiya, Harutaka (Kure Kyosai Hospital, Hiroshima (Japan))

    1994-04-01

    Computed tomography (CT) findings were assessed in 7 patients with malignant mesothelioma. CT findings were also reviewed in 9 patients with lung cancer and pleuritis carcinomatosa and in 11 patients with tuberculous pleuritis. Five patients with malignant mesothelioma underwent CT scans twice, on admission and from 1 to 7 months after admission. Tuberculous pleuritis could be distinguished from pleuritis carcinomatosa and malignant mesothelioma by the presence or absence of pleural nodularity and chest wall invasion. Although it was difficult to identify specific CT features clearly distinguishing malignant mesothelioma from pleuritis carcinomatosa, characteristic findings of malignant mesothelioma appeared to include the rapid development and progression of pleural rind and a tendency to spread directly into the chest wall. We divided the pleural into the four regions; upper anterior, upper posterior, lower anterior and lower posterior regions. Pleural changes were more frequently seen in the lower pleural regions than in the upper pleural regions in malignant mesothelioma. (author).

  1. Computed tomography findings of malignant pleural mesothelioma

    International Nuclear Information System (INIS)

    Shiota, Yutaro; Sato, Toshio; Yamaguchi, Kazuo; Ono, Tetsuya; Kaji, Masaro; Niiya, Harutaka

    1994-01-01

    Computed tomography (CT) findings were assessed in 7 patients with malignant mesothelioma. CT findings were also reviewed in 9 patients with lung cancer and pleuritis carcinomatosa and in 11 patients with tuberculous pleuritis. Five patients with malignant mesothelioma underwent CT scans twice, on admission and from 1 to 7 months after admission. Tuberculous pleuritis could be distinguished from pleuritis carcinomatosa and malignant mesothelioma by the presence or absence of pleural nodularity and chest wall invasion. Although it was difficult to identify specific CT features clearly distinguishing malignant mesothelioma from pleuritis carcinomatosa, characteristic findings of malignant mesothelioma appeared to include the rapid development and progression of pleural rind and a tendency to spread directly into the chest wall. We divided the pleural into the four regions; upper anterior, upper posterior, lower anterior and lower posterior regions. Pleural changes were more frequently seen in the lower pleural regions than in the upper pleural regions in malignant mesothelioma. (author)

  2. 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.)

  3. Computed tomography of Krukenberg tumors

    International Nuclear Information System (INIS)

    Cho, K.C.; Gold, B.M.

    1985-01-01

    Computed tomography (CT) of three patients with Kurkenberg tumor was reviewed retrospectively. CT showed large, lobulated, multicystic masses with soft-tissue components, indistinguishable from primary ovarian carcinoma. Much has been written about metastatic ovarian tumor, but this is the first report in the radiologic literature about their CT features. The authors emphasize the importance of recognizing the ovary as a frequent site of metastases and the proper approach to this problem. In patients with a history of colon or gastric carcinoma, the mixed cystic and solid ovarian mass on CT should be regarded as metastatic tumor until proven otherwise. A careful search for gastrointestinal tract signs or symptoms should be done in any patient with a pelvic tumor. When CT is done for evaluation of ovarian tumor, the stomach and colon should be carefully evaluated, and the ovaries routinely examined in the preoperative CT staging of gastric or colon carcinoma

  4. Computed tomography in spinal osteoblastoma

    International Nuclear Information System (INIS)

    Torricelli, P.; Martinelli, P.; Boriani, S.; Ferraro, A.

    1986-01-01

    In order to stress the role of computed tomography (CT) in the evaluation of benign spinal osteoblastoma, the authors examined by CT 10 patients with surgically and histologically proved osteoblastomas of the spine. Basing on surgical and histopathological findings CT proved to be a very important method for attesting the presence of the tumors (usually showed by radiographic examination), and specially for their staging and follow-up. CT in fact showed the real extent of the tumor into the spinal canal and towards the paraspinal soft tissues, and allowed the aerly detection of post surgical relapses. The authors conclude that CT is a primary diagnostic modality for preoperative planning and follow-up of benign osteoblastoma

  5. Computed tomography of calcaneal fractures

    International Nuclear Information System (INIS)

    Heger, L.; Wulff, K.; Seddiqi, M.S.A.

    1985-01-01

    Computed tomography (CT) of 25 fractured calcanei was performed to investigate the potential of CT in evaluating the pattern and biomechanics of these fractures. The characteristic findings of typical fractures are presented, including the number and type of principal fragments, size and dislocation of the sustentacular fragment, and involvement of the anterior and posterior facets of the subtalar joint. In 17 cases, the calcaneus consisted of four or more fragments. Furthermore, in 17 cases the sustentacular fragment included all or part of the posterior facet joint. In 18 of the 25 cases, the sustentacular fragment was displaced. It is concluded that well performed CT is an invaluable adjunct in understanding the fracture mechanism and in detecting pain-provoking impingement between the fibular malleolus and the tuberosity fragment

  6. Computed tomography of calcaneal fractures

    Energy Technology Data Exchange (ETDEWEB)

    Heger, L.; Wulff, K.; Seddiqi, M.S.A.

    1985-07-01

    Computed tomography (CT) of 25 fractured calcanei was performed to investigate the potential of CT in evaluating the pattern and biomechanics of these fractures. The characteristic findings of typical fractures are presented, including the number and type of principal fragments, size and dislocation of the sustentacular fragment, and involvement of the anterior and posterior facets of the subtalar joint. In 17 cases, the calcaneus consisted of four or more fragments. Furthermore, in 17 cases the sustentacular fragment included all or part of the posterior facet joint. In 18 of the 25 cases, the sustentacular fragment was displaced. It is concluded that well performed CT is an invaluable adjunct in understanding the fracture mechanism and in detecting pain-provoking impingement between the fibular malleolus and the tuberosity fragment.

  7. Computed tomography in sport injuries

    International Nuclear Information System (INIS)

    Reiser, M.; Rupp, N.

    1984-01-01

    Computed tomography (CT) provides axial slices plane and shows excellent details of bones and different soft tissues, favoring its use in traumatic lesions caused by sporting activities. Complex anatomical structures such as the shoulder, the vertebral column, the pelvis, the knee, the tarsal and carpal bones are often better recognized in detail than by conventional radiography. Fracture lines, localization of bone fragments and involvement of soft tissues are clearly demonstrated. Luxations and bone changes leading to luxations can be shown. CT arthrography provides for the first time a direct visualization of joint cartilage and of cruciate ligaments in the knee joint, so traumatic lesions such as chondropathia patellae or rupture of the cruciate ligaments are shown with a high degree of reliability. (orig.)

  8. Acute Calculous Cholecystitis Missed on Computed Tomography and Ultrasound but Diagnosed with Fluorodeoxyglucose-Positron Emission Tomography/Computed Tomography

    Directory of Open Access Journals (Sweden)

    Carina Mari Aparici

    2016-01-01

    Full Text Available We present a case of a 69-year-old patient who underwent ascending aortic aneurysm repair with aortic valve replacement. On postsurgical day 12, he developed leukocytosis and low-grade fevers. The chest computed tomography (CT showed a periaortic hematoma which represents a postsurgical change from aortic aneurysm repair, and a small pericardial effusion. The abdominal ultrasound showed cholelithiasis without any sign of cholecystitis. Finally, a fluorodeoxyglucose (FDG-positron emission tomography (PET/CT examination was ordered to find the cause of fever of unknown origin, and it showed increased FDG uptake in the gallbladder wall, with no uptake in the lumen. FDG-PET/CT can diagnose acute cholecystitis in patients with nonspecific clinical symptoms and laboratory results.

  9. Computed Tomography Scan and ICD Interaction

    Directory of Open Access Journals (Sweden)

    Jose M. Porres

    2009-01-01

    Full Text Available Although it has been considered a safe procedure, computed tomography scanning uses high doses of radiation and can cause malfunctioning in those patients with ICD when the radiation is directly incident on the device. We present a case of ventricular oversensing during a thoracic computed tomography.

  10. Appropriateness of computed tomography and magnetic resonance ...

    African Journals Online (AJOL)

    Appropriateness of computed tomography and magnetic resonance imaging scans in the Eden and Central Karoo districts of the Western Cape Province, South Africa. ... South African Medical Journal ... Computed tomography (CT) and magnetic resonance imaging (MRI) are an essential part of modern healthcare. Marked ...

  11. [Computed tomography and cranial paleoanthropology].

    Science.gov (United States)

    Cabanis, Emmanuel Alain; Badawi-Fayad, Jackie; Iba-Zizen, Marie-Thérèse; Istoc, Adrian; de Lumley, Henry; de Lumley, Marie-Antoinette; Coppens, Yves

    2007-06-01

    Since its invention in 1972, computed tomography (C.T.) has significantly evolved. With the advent of multi-slice detectors (500 times more sensitive than conventional radiography) and high-powered computer programs, medical applications have also improved. CT is now contributing to paleoanthropological research. Its non-destructive nature is the biggest advantage for studying fossil skulls. The second advantage is the possibility of image analysis, storage, and transmission. Potential disadvantages include the possible loss of files and the need to keep up with rapid technological advances. Our experience since the late 1970s, and a recent PhD thesis, led us to describe routine applications of this method. The main contributions of CT to cranial paleoanthropology are five-fold: --Numerical anatomy with rapid acquisition and high spatial resolution (helicoidal and multidetector CT) offering digital storage and stereolithography (3D printing). --Numerical biometry (2D and 3D) can be used to create "normograms" such as the 3D craniofacial reference model used in maxillofacial surgery. --Numerical analysis offers thorough characterization of the specimen and its state of conservation and/or restoration. --From "surrealism" to virtual imaging, anatomical structures can be reconstructed, providing access to hidden or dangerous zones. --The time dimension (4D imaging) confers movement and the possibility for endoscopic simulation and internal navigation (see Iconography). New technical developments will focus on data processing and networking. It remains our duty to deal respectfully with human fossils.

  12. Whole body positron emission tomography/computed tomography staging of metastatic choroidal melanoma.

    Science.gov (United States)

    Kurli, Madhavi; Reddy, Shantan; Tena, Lawrence B; Pavlick, Anna C; Finger, Paul T

    2005-08-01

    To evaluate whole-body positron emission tomography (PET)/computed tomography in staging of patients with metastatic choroidal melanoma. Interventional non-randomized clinical study. Twenty patients were referred for whole-body 18-fluoro-2-deoxy-D-glucose (FDG) PET/computed tomography imaging because of suspected metastatic choroidal melanoma. PET/computed tomography images were studied for the presence and distribution of metastatic melanoma. Subsequent biopsies were performed to confirm the presence of metastatic disease. Twenty patients underwent PET/computed tomography. Eighteen were imaged because of abnormal clinical, hematologic, or radiographic screening studies during the course of their follow-up after plaque brachytherapy or enucleation. Two were imaged before treatment of their primary tumor. PET/computed tomography revealed or confirmed metastatic melanoma in eight (40%) of these 20 patients. The mean time from initial diagnosis to metastasis was 47 months (range 0 to 154). The most common sites for metastases were the liver (100%), bone (50%), lung (25%), lymph nodes (25%), and subcutaneous tissue (25%). Cardiac, brain, thyroid, and posterior abdominal wall lesions (12.5%) were also noted. Six patients (75%) had multiple organ involvement. No false positives were noted. PET/computed tomography imaging also detected benign lesions of the bone and lymph nodes in three patients (15%). All patients had hepatic metastases and liver enzyme assays were abnormal in only one (12.5%) of eight patients. PET/computed tomography imaging is a sensitive tool for the detection and localization of hepatic and extra-hepatic (particularly osseous) metastatic choroidal melanoma.

  13. Errors in abdominal computed tomography

    International Nuclear Information System (INIS)

    Stephens, S.; Marting, I.; Dixon, A.K.

    1989-01-01

    Sixty-nine patients are presented in whom a substantial error was made on the initial abdominal computed tomography report. Certain features of these errors have been analysed. In 30 (43.5%) a lesion was simply not recognised (error of observation); in 39 (56.5%) the wrong conclusions were drawn about the nature of normal or abnormal structures (error of interpretation). The 39 errors of interpretation were more complex; in 7 patients an abnormal structure was noted but interpreted as normal, whereas in four a normal structure was thought to represent a lesion. Other interpretive errors included those where the wrong cause for a lesion had been ascribed (24 patients), and those where the abnormality was substantially under-reported (4 patients). Various features of these errors are presented and discussed. Errors were made just as often in relation to small and large lesions. Consultants made as many errors as senior registrar radiologists. It is like that dual reporting is the best method of avoiding such errors and, indeed, this is widely practised in our unit. (Author). 9 refs.; 5 figs.; 1 tab

  14. Cranial injuries and computer tomography

    International Nuclear Information System (INIS)

    Samejima, Kanji; Yoshii, Nobuo; Tobari, Chitoshi

    1979-01-01

    Patients, especially personal patients, with cerebral contusion and intracerebral hematoma were studied. Of 388 patients with cranial injuries who received computer tomography (CT) in our institute, 53 had cerebral contusion and 15 had intracerebral hematoma. CT revealed even hematoma at the parietal lobe or the inside of the cerebral hemispherium due to the cerebral contusion. The CT findings of cerebral contusion were classified into 3, that is, those with low density, those with high density, and those with non-homogenous density. From these findings cerebral edema rather than cerebral contusion was suspected. In patients with severe symptoms the basal cistern of the brain deformed and disappeared, frequently indicating that they had cerebral swellings. Only 20% of the patients with contusion at the brain-stem had abnormal CT findigns. Many patients with intracerebral hematoma complained headache, and these patients could be diagnosed easily by CT. In general it is believed that contrast enhancement is not necessary for patients with cranial injuries, but it was reported that 90% of patients with contusion showed enhancement after the use of contrast medium. (Ichikawa, K.)

  15. Computed Tomography of Interacerebral Hemorrhage

    International Nuclear Information System (INIS)

    Kim, Seung Hyeon; Lee, Jong Beum; Lee, Yong Chul; Lee, Kwan Seh; Park, Soo Soung

    1983-01-01

    Computed tomography (CT) is the most accurate and reliable method for the diagnosis of intracerebral and intraventricular hemorrhage. The precise anatomic extent of the nematoma, associated cerebral edema, ventricular deformity and displacement, and hydrocephalus are all readily assessed. Aside from head trauma, the principal cause of intracerebral hematoma is hypertensive vascular disease. Although hematomas from various causes may present similar CT appearances frequently the correct etiology may be suggested by consideration of patient's age, clinical history, and the location of the hematoma. The analytical study was performed in 180 cases of intracerebral hemorrhages by CT from October 1981 to January 1983. The results were as follows; 1. The most prevalent age group was 6th decade (37.2%). Male was prevalent to female at the ration of 1.6 to 1. 2. The most common symptom and sign was mental disturbance (48.7%), motor weakness (23%), headache (10.6%), nausea and vomiting (9.8%). 3. The causes of hemorrhage were hypertension (53.9%), head trauma (30.6%), aneurysm (6.1%) and A-V malformation (7.2%). 4. The frequent locations of hemorrhage were basal ganglia and thalamus (40.4%), lobes (35%), ventricles (21.8%). 5. The distribution of hemorrhage was intracerebral hemorrhage (65.6%), intracerebral and intraventricular hemorrhage (30.3%), intraventricular hemorrhage (4.4%).

  16. X-ray computed tomography

    International Nuclear Information System (INIS)

    Kalender, Willi A

    2006-01-01

    X-ray computed tomography (CT), introduced into clinical practice in 1972, was the first of the modern slice-imaging modalities. To reconstruct images mathematically from measured data and to display and to archive them in digital form was a novelty then and is commonplace today. CT has shown a steady upward trend with respect to technology, performance and clinical use independent of predictions and expert assessments which forecast in the 1980s that it would be completely replaced by magnetic resonance imaging. CT not only survived but exhibited a true renaissance due to the introduction of spiral scanning which meant the transition from slice-by-slice imaging to true volume imaging. Complemented by the introduction of array detector technology in the 1990s, CT today allows imaging of whole organs or the whole body in 5 to 20 s with sub-millimetre isotropic resolution. This review of CT will proceed in chronological order focussing on technology, image quality and clinical applications. In its final part it will also briefly allude to novel uses of CT such as dual-source CT, C-arm flat-panel-detector CT and micro-CT. At present CT possibly exhibits a higher innovation rate than ever before. In consequence the topical and most recent developments will receive the greatest attention. (review)

  17. Evaluation of computed tomography for obstructive jaundice

    International Nuclear Information System (INIS)

    Matsuoka, Shoji; Toda, Hiroshi; Suzuki, Toshihiko

    1980-01-01

    Findings of computed tomography were reviewed in 54 cases where obstructive jaundice was suggested by liver function studies and computed tomography was done with the diagnosis subsequently confirmed by surgery. Dilatation of the intrahepatic bile duct was found in 49 (91%) of the cases and the site of obstruction was determined in 44 cases (82%). The cause was shown in 28 cases (52%). By disease, the cause was correctly diagnosed with gallbladder in 40%, bile duct cancer in 46%, pancreas cancer in 71%, and choledocal cyst in 100%, but cholelithiasis was diagnosed correctly in only 17%. Further, non-calcium cholelithiasis is very difficult to diagnose by computed tomography. Computed tomography is a useful tool for diagnosis of obstructive jaundice as a noninvasive means of evaluating the patient; however, concomitand use of other diagnostic studies is essential for greater accuracy of diagnosis. (author)

  18. Bladder hernia: Multidetector computed tomography findings

    Directory of Open Access Journals (Sweden)

    Ankur Gadodia

    2011-01-01

    Full Text Available Herniation of bladder in inguinal hernia is rare, with most cases diagnosed intraoperatively. Preoperative diagnosis is even rarer. We report a case of bladder as content of inguinal hernia diagnosed using multidetector computed tomography.

  19. Quantitative computed tomography evaluation of pulmonary disease

    DEFF Research Database (Denmark)

    McEvoy, Fintan; Buelund, Lene Elisabeth; Strathe, Anders Bjerring

    2009-01-01

    Objective assessment of pulmonary disease from computed tomography (CT) examinations is desirable but difficult. When such assessments can be made, it is important that they are related to some part of the pathophysiologic process present....

  20. Iterative Reconstruction for Cardiopulmonary Computed Tomography

    NARCIS (Netherlands)

    Willemink, M.J.

    2015-01-01

    Introduction The number of computed tomography (CT) examinations has increased rapidly since CT became commercially available. This resulted in growing concerns regarding the risk of malignancies induced by application of medical ionizing radiation. Therefore, radiation dose reduction strategies

  1. Examination of weld defects by computed tomography

    Directory of Open Access Journals (Sweden)

    M. Jovanović

    2012-04-01

    Full Text Available Defects in metal arc gas (MAG welds made in S235JR low carbon steel of 6 mm thickness were examined. A sample containing lack of fusion (LOF and pores was examined by computed tomography – CT. The computed tomography examination was performed in order to define LOF size and position as well as dimensions and distribution of accompanying pores in the weld metal.

  2. Dose optimization in computed tomography: ICRP 87

    International Nuclear Information System (INIS)

    2007-01-01

    The doses given in the use of computed tomography scans are studied, aiming to calibrate the limits of irradiation in patients who need these tests. Furthermore, a good value of computed tomography should be guaranteed by physicians and radiologists for people not being irradiated unfairly, reducing doses and unnecessary tests. A critical evaluation by an ethics committee is suggested for cases where the test is performed for medical research without a cause [es

  3. Computed tomography in abnormalities of the hip

    Energy Technology Data Exchange (ETDEWEB)

    Visser, J.D.; Jonkers, A.; Klasen, H.J. (Rijksuniversiteit Groningen (Netherlands). Academisch Ziekenhuis); Hillen, B. (Rijksuniversiteit Groningen (Netherlands). Lab. voor Anatomie en Embryologie)

    1982-06-26

    The value of computed tomography in the assessment of abnormalities of the hip is demonstrated with the aid of an anatomical preparation and in patients with, respectively, congenital dislocation of a hip, dislocation of the hip in spina bifida, an acetabular fracture and a Ewing tumour. The anteversion of the acetabulum and femur and the instability index of the hip joint can be measured by means of computed tomography.

  4. Children's (Pediatric) CT (Computed Tomography)

    Medline Plus

    Full Text Available ... tomography, more commonly known as a CT or CAT scan, is a diagnostic medical test that, like ... imaging provides real-time imaging, making it a good tool for guiding minimally invasive procedures such as ...

  5. Incidental head and neck findings on 18F-fluoro-deoxy-glucose positron emission tomography computed tomography.

    Science.gov (United States)

    Williams, S P; Kinshuck, A J; Williams, C; Dwivedi, R; Wieshmann, H; Jones, T M

    2015-09-01

    The overlapping risk factors for lung and head and neck cancer present a definite risk of synchronous malignant pathology. This is the first study to specifically review incidental positron emission tomography computed tomography findings in the head and neck region in lung carcinoma patients. A retrospective review was performed of all lung cancer patients who underwent positron emission tomography computed tomography imaging over a five-year period (January 2008 - December 2012), identified from the Liverpool thoracic multidisciplinary team database. Six hundred and nine patients underwent positron emission tomography computed tomography imaging over this period. In 76 (12.5 per cent) scans, incidental regions of avid 18F-fluoro-deoxy-glucose uptake were reported in the head and neck region. In the 28 patients who were fully investigated, there were 4 incidental findings of malignancy. In lung cancer patients undergoing investigative positron emission tomography computed tomography scanning, a significant number will also present with areas of clinically significant 18F-fluoro-deoxy-glucose uptake in the head and neck region. Of these, at least 5 per cent may have an undiagnosed malignancy.

  6. Computed tomography in diagnosis of hepatic abscess

    International Nuclear Information System (INIS)

    Sui, Osamu; Kurooka, Nobuyuki; Shirono, Ryozo

    1984-01-01

    Fourteen patients with hepatic abscess were evaluated by computed tomography (CT), who underwent surgical drainage. Eight cases were due to biliary tract infection and two were due to pylephlebitis of portal vein. Four cases were cryptogenic. Hepatic abscesses tended to be located in the right lobe of the liver. All of them appeared as low-density areas on plain CT scans and most of them were smooth-marginated and well-circumscribed. We classified the CT findings of the hepatic abscesses into three types; type 1: homogeneous low-density area, type 2: inhomogeneous low-density area, type 3: low-density mass surrounded by poorly-circumscribed low attenuation value area. In type 3 of the hepatic abscesses, poorly-circumscribed low attenuation value area was enhanced after the i.v. injection of contrast medium and was nearly imperceptible. Type 3 was thought to be characteristic of the hepatic abscess. Other CT findings such as pneumobilia, intrahepatic ductal stone, cholecystolithiasis and so on were also useful for the diagnosis of the hepatic abscess. (author)

  7. Computed tomography in diagnosis of hepatic abscess

    Energy Technology Data Exchange (ETDEWEB)

    Sui, Osamu; Kurooka, Nobuyuki; Shirono, Ryozo (Tokushima Univ. (Japan). School of Medicine)

    1984-10-01

    Fourteen patients with hepatic abscess were evaluated by computed tomography (CT), who underwent surgical drainage. Eight cases were due to biliary tract infection and two were due to pylephlebitis of portal vein. Four cases were cryptogenic. Hepatic abscesses tended to be located in the right lobe of the liver. All of them appeared as low-density areas on plain CT scans and most of them were smooth-marginated and well-circumscribed. We classified the CT findings of the hepatic abscesses into three types; type 1: homogeneous low-density area, type 2: inhomogeneous low-density area, type 3: low-density mass surrounded by poorly-circumscribed low attenuation value area. In type 3 of the hepatic abscesses, poorly-circumscribed low attenuation value area was enhanced after the i.v. injection of contrast medium and was nearly imperceptible. Type 3 was thought to be characteristic of the hepatic abscess. Other CT findings such as pneumobilia, intrahepatic ductal stone, cholecystolithiasis and so on were also useful for the diagnosis of the hepatic abscess.

  8. Positron emission tomography/computed tomography scanning for ...

    African Journals Online (AJOL)

    Background: Although the site of nosocomial sepsis in the critically ill ventilated patient is usually identifiable, it may remain occult, despite numerous investigations. The rapid results and precise anatomical location of the septic source using positron emission tomography (PET) scanning, in combination with computed ...

  9. The Comparison of Computed Tomography Perfusion, Contrast-Enhanced Computed Tomography and Positron-Emission Tomography/Computed Tomography for the Detection of Primary Esophageal Carcinoma.

    Science.gov (United States)

    Genc, Berhan; Kantarci, Mecit; Sade, Recep; Orsal, Ebru; Ogul, Hayri; Okur, Aylin; Aydin, Yener; Karaca, Leyla; Eroğlu, Atilla

    2016-01-01

    The purpose of this study was to investigate the efficiency of computed tomography perfusion (CTP), contrast-enhanced computed tomography (CECT) and 18F-fluoro-2-deoxy-D-glucose (18F-FDG) positron-emission tomography (PET/CT) in the diagnosis of esophageal cancer. This prospective study consisted of 33 patients with pathologically confirmed esophageal cancer, 2 of whom had an esophageal abscess. All the patients underwent CTP, CECT and PET/CT imaging and the imaging findings were evaluated. Sensitivity, specificity and positive and negative predictive values were calculated for each of the 3 imaging modalities relative to the histological diagnosis. Thirty-three tumors were visualized on CTP, 29 on CECT and 27 on PET/CT. Six tumors were stage 1, and 2 and 4 of these tumors were missed on CECT and PET/CT, respectively. Significant differences between CTP and CECT (p = 0.02), and between CTP and PET/CT (p = 0.04) were found for stage 1 tumors. Values for the sensitivity, specificity and positive and negative predictive values on CTP were 100, 100, 100 and 100%, respectively. Corresponding values on CECT were 93.94, 0, 93.94 and 0%, respectively, and those on PET/CT were 87.88, 0, 93.55 and 0%, respectively. Hence, the sensitivity, specificity and positive and negative predictive values of CTP were better than those of CECT and PET/CT. CTP had an advantage over CECT and PET/CT in detecting small lesions. CTP was valuable, especially in detecting stage 1 tumors. © 2016 S. Karger AG, Basel.

  10. Computed tomography diagnosis of distal radioulnar subluxation

    International Nuclear Information System (INIS)

    Wechsler, R.J.; Rifkin, M.D.; Edeiken, J.; Branch, H.M.

    1987-01-01

    Eight patients with suspected diagnosis of distal radioulnar joint (DRUJ) subluxation underwent computed tomographic (CT) scans of the wrist. Five underwent surgery and had DRUJ subluxation or dislocation; CT scans revealed subluxation in four. Three CT criteria for the evaluation of DRUJ subluxation are discussed and compared in this manuscript. (orig.)

  11. Is there any role of positron emission tomography computed tomography for predicting resectability of gallbladder cancer?

    Science.gov (United States)

    Kim, Jaihwan; Ryu, Ji Kon; Kim, Chulhan; Paeng, Jin Chul; Kim, Yong-Tae

    2014-05-01

    The role of integrated (18)F-2-fluoro-2-deoxy-D-glucose positron emission tomography computed tomography (PET-CT) is uncertain in gallbladder cancer. The aim of this study was to show the role of PET-CT in gallbladder cancer patients. Fifty-three patients with gallbladder cancer underwent preoperative computed tomography (CT) and PET-CT scans. Their medical records were retrospectively reviewed. Twenty-six patients underwent resection. Based on the final outcomes, PET-CT was in good agreement (0.61 to 0.80) with resectability whereas CT was in acceptable agreement (0.41 to 0.60) with resectability. When the diagnostic accuracy of the predictions for resectability was calculated with the ROC curve, the accuracy of PET-CT was higher than that of CT in patients who underwent surgical resection (P=0.03), however, there was no difference with all patients (P=0.12). CT and PET-CT had a discrepancy in assessing curative resection in nine patients. These consisted of two false negative and four false positive CT results (11.3%) and three false negative PET-CT results (5.1%). PET-CT was in good agreement with the final outcomes compared to CT. As a complementary role of PEC-CT to CT, PET-CT tended to show better prediction about resectability than CT, especially due to unexpected distant metastasis.

  12. Children's (Pediatric) CT (Computed Tomography)

    Medline Plus

    Full Text Available ... images. These images can be viewed on a computer monitor, printed on film or transferred to a ... a gantry, which rotates around the patient. The computer that processes the imaging information and monitor are ...

  13. Children's (Pediatric) CT (Computed Tomography)

    Medline Plus

    Full Text Available ... which rotates around the patient. The computer that processes the imaging information and monitor are located in ... follows a spiral path. A special computer program processes this series of pictures, or slices of the ...

  14. Indication for dental computed tomography. Case reports

    International Nuclear Information System (INIS)

    Schom, C.; Engelke, W.; Kopka, L.; Fischer, U.; Grabbe, E.

    1996-01-01

    Based on case reports, common indications for dental computed tomography are demonstrated and typical findings are analysed. From a group of 110 patients who had a reformatted computed tomography of the maxilla and mandibula, 10 typical cases were chosen as examples and are presented with a detailed description of the findings. The most important indication was the analysis of the morphology of the alveolar ridge needed in presurgical planning for osseointegrated implants as well as in special cases of postsurgical control. Apart from implantology, the method could be used in cases of mandibular cysts and bony destructions. In conclusion, dental computed tomography has become established mainly in implantology. It can provide valuable results in cases where a demonstration of the bone in all dimensions and free of overlappings and distortions is needed. (orig.) [de

  15. Computed tomography of oesophageal carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Muehling, T.; Kuklinski, M.E.; Huebsch, T.; Witte, J.

    1985-08-01

    Between March, 1980 and January, 1984, computerized tomography (CT) was performed on 110 patients with proven esophageal carcinoma. In 26 patients, information obtained preoperatively by CT was compared with results of intraoperative exploration or histologic examination of resection specimen. Correlation analysis showed that accuracy of CT in assessing actual tumor size and mediastinal or abdominal lymphnode involvement is rather limited, while correct results were obtained in between 84 and 100 percent of patients as far as identification of invasion of adjacent organs is concerned. We thus advocate routine use of CT in the process of preoperative assessment of operability and staging.

  16. The Western Denmark Cardiac Computed Tomography Registry

    DEFF Research Database (Denmark)

    Nielsen, Lene Hüche; Nørgaard, Bjarne Linde; Tilsted, Hans-Henrik

    2015-01-01

    BACKGROUND: As a subregistry to the Western Denmark Heart Registry (WDHR), the Western Denmark Cardiac Computed Tomography Registry (WDHR-CCTR) is a clinical database established in 2008 to monitor and improve the quality of cardiac computed tomography (CT) in Western Denmark. OBJECTIVE: We...... positive and negative predictive values for both university (96%/99%) and nonuniversity centers (97%/99%). CONCLUSION: WDHR-CCTR provides ongoing prospective registration of all cardiac CTs performed in Western Denmark since 2008. Overall, the registry data have a high degree of completeness and validity...

  17. Epiploic appendicitis - ultrasonography and computed tomography findings

    International Nuclear Information System (INIS)

    Melo, Alessandro Severo Alves de; Alves, Jose Ricardo Duarte; . E-mail: lubiamoreira@bol.com.br; Moreira, Luiza Beatriz Melo; Pinheiro, Ricardo Andrade; Noro, Fabio; )

    2002-01-01

    Epiploic appendicitis is an uncommon inflammatory condition, which is presently better diagnosed by current imaging methods such as computed tomography and ultrasonography that allow a non-invasive and efficient diagnostic approach. The author studied 6 patients with epiploic appendicitis. The patients were submitted to computed tomography that showed paracolic oval lesions of 1 to 2 cm of diameter, fat attenuation and a thin peripheral hyperdense rim associated with adjacent fat stranding. Ultrasound examination performed in two patients showed hyperechoic ovoid noncompressible masses at the site of maximum abdominal tenderness. (author)

  18. Computed tomography in malignant primary bone tumours

    International Nuclear Information System (INIS)

    Kersjes, W.; Harder, T.; Haeffner, P.

    1990-01-01

    The importance of computed tomography is examined in malignant primary bone tumours using a strongly defined examination group of 13 Patients (six Ewing's-sarcomas, five osteosarcomas, one chondrosarcoma and one spindle-shaped cell sarcoma). Computed tomography is judged superior compared to plain radiographs in recognition of bone marrow infiltration and presentation of parosteal tumour parts as well as in analysis of tissue components of tumours, CT is especially suitable for therapy planning and evaluating response to therapy. CT does not provide sufficient diagnostic information to determine dignity and exact diagnosis of bone tumours. (orig.) [de

  19. Computed tomography of sacro-iliac joints

    International Nuclear Information System (INIS)

    Miquel, A.; Laredo, J.D.

    1995-01-01

    Actual technologies to explore sacro-iliac joints are conventional radiography, computed tomography , scintigraphy and nuclear magnetic resonance imaging. Standards films are sufficient, except in beginning sacro-iliac septic inflammations where the computed tomography is superior. Two problems are generally posed for the radiologist, to differentiate a septic arthritis from a rheumatic pathology An other problem in diagnosis is to make the difference between a degenerative arthropathy (which does not need a further investigation) and an infectious rheumatic pathology where more exploration is necessary. 28 refs., 3 tabs., 13 figs

  20. Children's (Pediatric) CT (Computed Tomography)

    Medline Plus

    Full Text Available ... be viewed on a computer monitor, printed on film or transferred to a CD or DVD. CT ... through the body, recording an image on photographic film or a special image recording plate . Bones appear ...

  1. Children's (Pediatric) CT (Computed Tomography)

    Medline Plus

    Full Text Available ... computer software, the result is a very detailed multidimensional view of the body's interior. Refinements in detector ... community, you can search the ACR-accredited facilities database . This website does not provide cost information. The ...

  2. Children's (Pediatric) CT (Computed Tomography)

    Medline Plus

    Full Text Available ... slices. When the image slices are reassembled by computer software, the result is a very detailed multidimensional view of the body's interior. Refinements in detector technology allow new CT scanners to obtain multiple slices ...

  3. Children's (Pediatric) CT (Computed Tomography)

    Medline Plus

    Full Text Available ... which are then displayed on a monitor. Special software can also generate three-dimensional (3-D) images ... When the image slices are reassembled by computer software, the result is a very detailed multidimensional view ...

  4. Children's (Pediatric) CT (Computed Tomography)

    Medline Plus

    Full Text Available ... child may have, and if there is a history of heart disease, asthma, diabetes, kidney disease or ... a gantry, which rotates around the patient. The computer that processes the imaging information and monitor are ...

  5. The value of positron emission tomography/computed tomography for evaluating metastatic disease in patients with pancreatic cancer.

    Science.gov (United States)

    Kim, Mi-Jin; Lee, Kwang Hyuck; Lee, Kyu Taek; Lee, Jong Kyun; Ku, Bon-Ho; Oh, Cho-Rong; Heo, Jin Seok; Choi, Seong-Ho; Choi, Dong Wook

    2012-08-01

    Routine application of positron emission tomography/computed tomography (PET/CT) for pancreatic cancer staging remains a controversial approach. The purpose of this study was to reassess the clinical impact of PET/CT for the detection of distant metastasis of pancreatic cancer. From January 2006 to June 2009, 125 patients with histologically proven pancreatic cancer that had undergone PET/CT at our hospital were retrospectively reviewed. To evaluate the clinical efficacy of PET/CT on the management plan, the post-PET/CT management plans were compared with the pre-PET/CT management plans. After the conventional staging workup, we determined that 76 patients (60.8%) had resectable lesions, whereas 48 patients had unresectable lesions. One patient underwent explorative laparotomy due to equivocal resectability. Positron emission tomography/computed tomography diagnosed distant metastasis in only 2 (2.6%) of the 76 patients with resectable lesions, and these patients did not undergo unnecessary surgical treatment. Complete resection was not performed in 8 of the 74 operative patients because they had distant metastasis detected during the operative procedure. Positron emission tomography/computed tomography diagnosed distant metastasis in 32 of the 44 patients with metastatic lesions that were histologically shown to have sensitivity of 72.7%. Positron emission tomography/computed tomography has a limited role in the evaluation of metastatic disease from pancreatic cancer.

  6. Computed Tomography. Evolution, technical principles and applications

    International Nuclear Information System (INIS)

    Calzado, A.; Geleijns, J.

    2010-01-01

    Computed tomography has become one of the most commonly used diagnostic techniques. Since its clinical introduction in 1971, subsequent developments have led to the emergence of new indications in different medical specialties. This paper reviews the evolution of art; essential characteristics of CT scanners are described and different application modalities in diagnosis are reviewed as well. (Author).

  7. Computed tomography (CT) and diastematomyelia's diagnosis

    International Nuclear Information System (INIS)

    Santos, M.B. dos; Luca, V. de; Ferreira, M.A.S.; Barros, A.P. de

    1982-01-01

    After a case of diastematomyelia observed at the University Hospital (Federal University of Rio de Janeiro, Brazil) a review is done of the pertaining literature, and the contribution of the computed tomography for the diagnosis of this disease is emphasized. (Author) [pt

  8. Computed tomography evaluation of petrous bone fractures ...

    African Journals Online (AJOL)

    Background: Petrous bone trauma is the sequel of blunt head injury and can have life threatening complications resulting in immediate mortality. Early detection and good knowledge of the Computed Tomography (CT) findings ensure prompt treatment of both fractures and complications. Objective: To document the ...

  9. Coordinate Metrology by Traceable Computed Tomography

    DEFF Research Database (Denmark)

    Müller, Pavel

    X-ray computed tomography (CT) is a measuring technique which has become an important technology in the production environment over the last years. Due to a number of advantages of CT compared to, e.g., coordinate measuring machines (CMMs), CT has been recently spread in the field of manufacturin...

  10. Neutron computed tomography of rat lungs.

    Science.gov (United States)

    Metzke, R W; Runck, H; Stahl, C A; Schillinger, B; Calzada, E; Mühlbauer, M; Schulz, M; Schneider, M; Priebe, H-J; Wall, W A; Guttmann, J

    2011-01-07

    Using conventional methods, three-dimensional imaging of the lung is challenging because of the low contrast between air and tissue and the large differences in dimensions between various pulmonary structures. The small distal airway structures and the high air-to-tissue ratio of lung tissue require an imaging technique which reliably discriminates between air and water. The objective of this study was to assess whether neutron computed tomography would satisfy such a requirement. This method utilizes the unique characteristic of neutrons of directly interacting with the atomic nucleus rather than being scattered by the atomic shell. Neutron computed tomography was tested in rats and allowed differentiation of larger lung structures (e.g., lobes) and distal airways. Airways could be identified reliably down to the sixth bronchial generation, in some cases even down to the tenth generation. The lung could be stabilized for sufficiently long exposure times to achieve an image resolution of 50-60 µm, which is the current physical resolution limit of the neutron computed tomography facility. Neutron computed tomography allowed excellent lung imaging without the need for additional tissue preparation or contrast media. The enhanced structural resolution obtained by applying this new research technique may improve understanding of lung physiology and respiratory therapy.

  11. Computed Tomography Analysis of NASA BSTRA Balls

    Energy Technology Data Exchange (ETDEWEB)

    Perry, R L; Schneberk, D J; Thompson, R R

    2004-10-12

    Fifteen 1.25 inch BSTRA balls were scanned with the high energy computed tomography system at LLNL. This system has a resolution limit of approximately 210 microns. A threshold of 238 microns (two voxels) was used, and no anomalies at or greater than this were observed.

  12. Computed tomography in severe protein energy malnutrition.

    OpenAIRE

    Househam, K C; de Villiers, J F

    1987-01-01

    Computed tomography of the brain was performed on eight children aged 1 to 4 years with severe protein energy malnutrition. Clinical features typical of kwashiorkor were present in all the children studied. Severe cerebral atrophy or brain shrinkage according to standard radiological criteria was present in every case. The findings of this study suggest considerable cerebral insult associated with severe protein energy malnutrition.

  13. Computed tomography of the iliopsoas muscle

    International Nuclear Information System (INIS)

    Nino-Murcia, M.; Wechsler, R.J.; Brennan, R.E.

    1983-01-01

    Computed tomography (CT) is an ideal method for the imaging of the psoas muscle. The authors present 13 cases of patients with psoas abnormalities diagnosed by CT. The CT features of the different pathologic entities and comparison of CT with other imaging modalities are discussed. (orig.)

  14. Diagnostic reference levels for paediatric computed tomography ...

    African Journals Online (AJOL)

    Objectives: To establish local diagnostic reference levels (LDRLs) for emergency paediatric head computed tomography (CT) scans performed at a South ... LDRL values were compared with several national DRLs from Europe and Australia. ... Standard age stratification for DRL and LDRL reporting is recommended.

  15. Cone beam computed tomography in veterinary dentistry

    NARCIS (Netherlands)

    van Thielen, B.; Siguenza, F.; Hassan, B.

    2012-01-01

    The purpose of this study was to assess the feasibility of cone beam computed tomography (CBCT) in imaging dogs and cats for diagnostic dental veterinary applications. CBCT scans of heads of six dogs and two cats were made. Dental panoramic and multi-planar reformatted (MPR) para-sagittal

  16. Multislice computed tomography in an asymptomatic high-risk population.

    Science.gov (United States)

    Romeo, Francesco; Leo, Roberto; Clementi, Fabrizio; Razzini, Cinzia; Borzi, Mauro; Martuscelli, Eugenio; Pizzuto, Francesco; Chiricolo, Gaetano; Mehta, Jawahar L

    2007-02-01

    Approximately 50% of all acute coronary syndromes occur in previously asymptomatic patients. This study evaluated the value of multislice computed tomography for early detection of significant coronary artery disease (CAD) in high-risk asymptomatic subjects. One hundred sixty-eight asymptomatic subjects with >or=1 major risk factor (hypertension, diabetes, hypercholesterolemia, family history, or smoking) and an inconclusive or unfeasible noninvasive stress test result (stress electrocardiography, echocardiography, or nuclear scintigraphy) were evaluated in an outpatient setting. After clinical examination and laboratory risk analysis, all patients underwent multislice computed tomographic (MSCT) coronary angiography within 1 week. In all subjects, conventional coronary angiography was also carried out. Multislice computed tomography displayed single-vessel CAD in 16% of patients, 2-vessel CAD in 7%, and 3-vessel CAD in 4%. Selective coronary angiography confirmed the results of multislice computed tomography in 99% of all patients. Sensitivity and specificity of MSCT coronary angiography were 100% and 98%, respectively, with a positive predictive value of 95% and a negative predictive value of 100%. In conclusion, MSCT coronary angiography is an excellent noninvasive technique for early identification of significant CAD in high-risk asymptomatic patients with inconclusive or unfeasible noninvasive stress test results.

  17. Computed tomography of tuberculous meningitis

    International Nuclear Information System (INIS)

    Sato, Noriko; Sato, Hiromi; Kawaguchi, Tetsuro; Fujita, Katsuzo; Tanaka, Makoto

    1982-01-01

    Recently, tuberculous meningitis has become rather rare except in areas where tuberculosis is still endemic. Six adolescents and young adults with tuberculous meningitis were evaluated by means of serial computerized tomography (CT), and the results were correlated with the findings of surgical specimens or autopsies. All cases showed meningeal irritation and fever at onset. CSF cultures revealed the presence of tuberculous bacilli. Four cases advanced rapidly to the clinical stage III and expired in a short period-between two weeks to one month from onset. On initial CT scanning, the disappearance of the basal cistern was a characteristic finding in all these cases. With the progression, an enhancement of the basal cistern on contrast injection, a localized hypodensity in adjacent parenchyma, and symmetrical ventricular dilatation appeared. Two autopsied cases showed tuberculous granulomas with purulent materials, thickened meninges, and caseous necrosis in the parenchyma around the basal cistern. The other two cases progressed rather slowly. CT findings at Stage II showed multiple enhanced spots in the basal subcortical area following contrast injection. Tuberculous granulomas were identified in these parts by means of explorative craniotomy. The authors point out the pathognomonic CT findings of tuberculous meningitis and emphasize the necessity of serial CT for the early detection and management of tuberculous meningitis. (author)

  18. Computed tomography of tuberculous meningitis

    Energy Technology Data Exchange (ETDEWEB)

    Sato, Noriko; Sato, Hiromi; Kawaguchi, Tetsuro; Fujita, Katsuzo; Tanaka, Makoto (Kobe Univ. (Japan). School of Medicine)

    1982-12-01

    Recently, tuberculous meningitis has become rather rare except in areas where tuberculosis is still endemic. Six adolescents and young adults with tuberculous meningitis were evaluated by means of serial computerized tomography (CT), and the results were correlated with the findings of surgical specimens or autopsies. All cases showed meningeal irritation and fever at onset. CSF cultures revealed the presence of tuberculous bacilli. Four cases advanced rapidly to the clinical stage III and expired in a short period-between two weeks to one month from onset. On initial CT scanning, the disappearance of the basal cistern was a characteristic finding in all these cases. With the progression, an enhancement of the basal cistern on contrast injection, a localized hypodensity in adjacent parenchyma, and symmetrical ventricular dilatation appeared. Two autopsied cases showed tuberculous granulomas with purulent materials, thickened meninges, and caseous necrosis in the parenchyma around the basal cistern. The other two cases progressed rather slowly. CT findings at Stage II showed multiple enhanced spots in the basal subcortical area following contrast injection. Tuberculous granulomas were identified in these parts by means of explorative craniotomy. The authors point out the pathognomonic CT findings of tuberculous meningitis and emphasize the necessity of serial CT for the early detection and management of tuberculous meningitis.

  19. Children's (Pediatric) CT (Computed Tomography)

    Medline Plus

    Full Text Available Toggle navigation Test/Treatment Patient Type Screening/Wellness Disease/Condition Safety En Español More Info Images/Videos About Us News Physician Resources Professions Site Index A-Z Children's (Pediatric) CT (Computed ...

  20. 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

  1. Thermoluminescent dosimetry in computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Lara C, A.; Rivera M, T. [IPN, Centro de Investigacion en Ciencia Aplicada y Tecnologia Avanzada, Unidad Legaria, Av. Legaria 694, Col. Irrigacion, 11500 Ciudad de Mexico (Mexico); Osorio V, M. [ISSSTE, Centro Medico Nacional 20 de Noviembre, Felix Cuevas 540, Col. del Valle, 03100 Ciudad de Mexico (Mexico); Hernandez O, O., E-mail: armando_lara_cam@yahoo.com.mx [Hospital General de Mexico, Dr. Balmis 148, Col. Doctores, 06726 Ciudad de Mexico (Mexico)

    2016-10-15

    In this work we studied the dosimetry performed on CT scan in two different equipment, SOMATOM and Phillips, with 16 and 64 slice respectively. We used 51 pellets of lithium fluoride doped with magnesium and titanium (LiF: Mg, Ti) also knows as TLD-100 due to its physical properties and its easy of use, in this study, first analysis a batch of 56 pellets, but only 53 pellets were optimal for this study, cesium-137 was used as source irradiation, then proceeded to calibrate the batch with X-rays source, measuring the corresponding dose in a Farmers ionization chamber, then, we obtained a calibration curve, and we used as reference to calculation of the applied dose, finally designing ergonomic mesh, were it was deposited a TLD 100, placed in a regions of interest were made to each scan type. Once characterized our material proceeded to testing in 30 patients, which were irradiated with X-ray tube, whose operation was performed at 80, 120 kV with a current of 100, 300 and 400 m A according to scanning protocol. Overall we measured dose of 5 mGy to 53 mGy, these measurements reflect significant dose to can induced cancer, due previous reports published, that doses greater than 20 mGy there is a risk of developing cancer in the long term, but in practice when it assigned a medical diagnosis, there are no dose limits due to benefits patients, however, IAEA publish recommendations that allow us to carry out optimum handling of ionizing radiation, among these is the quality control of the tomography equipment that helps greatly reduce patient dose. (Author)

  2. Thermoluminescent dosimetry in computed tomography

    International Nuclear Information System (INIS)

    Lara C, A.; Rivera M, T.; Osorio V, M.; Hernandez O, O.

    2016-10-01

    In this work we studied the dosimetry performed on CT scan in two different equipment, SOMATOM and Phillips, with 16 and 64 slice respectively. We used 51 pellets of lithium fluoride doped with magnesium and titanium (LiF: Mg, Ti) also knows as TLD-100 due to its physical properties and its easy of use, in this study, first analysis a batch of 56 pellets, but only 53 pellets were optimal for this study, cesium-137 was used as source irradiation, then proceeded to calibrate the batch with X-rays source, measuring the corresponding dose in a Farmers ionization chamber, then, we obtained a calibration curve, and we used as reference to calculation of the applied dose, finally designing ergonomic mesh, were it was deposited a TLD 100, placed in a regions of interest were made to each scan type. Once characterized our material proceeded to testing in 30 patients, which were irradiated with X-ray tube, whose operation was performed at 80, 120 kV with a current of 100, 300 and 400 m A according to scanning protocol. Overall we measured dose of 5 mGy to 53 mGy, these measurements reflect significant dose to can induced cancer, due previous reports published, that doses greater than 20 mGy there is a risk of developing cancer in the long term, but in practice when it assigned a medical diagnosis, there are no dose limits due to benefits patients, however, IAEA publish recommendations that allow us to carry out optimum handling of ionizing radiation, among these is the quality control of the tomography equipment that helps greatly reduce patient dose. (Author)

  3. Microfocus computed tomography in medicine

    Science.gov (United States)

    Obodovskiy, A. V.

    2018-02-01

    Recent advances in the field of high-frequency power schemes for X-ray devices allow the creation of high-resolution instruments. At the department of electronic devices and Equipment of the St. Petersburg State Electrotechnical University, a model of a microfocus computer tomograph was developed. Used equipment allows to receive projection data with an increase up to 100 times. A distinctive feature of the device is the possibility of implementing various schemes for obtaining projection data.

  4. Cerebral candidiasis. Computed tomography appearance

    International Nuclear Information System (INIS)

    Chaabane, M.; Ladeb, M.F.; Bouhaouala, M.H.; Ben Hammouda, M.; Ataalah, R.; Gannouni, A.; Krifa, H.

    1989-01-01

    A three year old child who had been suffering from oral candidiasis since the age of 1 year presented with osteitis of the clavicle, 2 cerebral frontal abscesses and an occipital abscess which extended across the calvaria and was associated with osteolysis. Histological and microbiological studies following surgery confirmed the diagnosis of candidiasis in this girl who was found to have IgA immunodefinciency. The authors report the computed tomographic appearance of the cerebral lesions and review the literature. (orig.)

  5. Cerebral candidiasis. Computed tomography appearance

    Energy Technology Data Exchange (ETDEWEB)

    Chaabane, M.; Ladeb, M.F.; Bouhaouala, M.H.; Ben Hammouda, M.; Ataalah, R.; Gannouni, A.; Krifa, H.

    1989-07-01

    A three year old child who had been suffering from oral candidiasis since the age of 1 year presented with osteitis of the clavicle, 2 cerebral frontal abscesses and an occipital abscess which extended across the calvaria and was associated with osteolysis. Histological and microbiological studies following surgery confirmed the diagnosis of candidiasis in this girl who was found to have IgA immunodefinciency. The authors report the computed tomographic appearance of the cerebral lesions and review the literature. (orig.).

  6. Orbital computed tomography: technical aspects

    International Nuclear Information System (INIS)

    Beck, T.J.; Rosenbaum, A.E.; Miller, N.R.

    1982-01-01

    Computed tomographic scanning has revolutionized the diagnosis and management of orbital disease. The best use of this methodology requires knowledge of the principles and appropriate attention to scanning protocols. Computed tomographic scanning of the orbit is a demanding technique requiring thin sections through planes precisely positioned from the topographical anatomy. Ideally, orbital CT should include both transverse axial and coronal sections: The pathological condition and its plane of growth will influence the selection of the optimal plane or section. Coronal sections may be obtained either directly or indirectly by computer reconstruction from contiguous transverse images. Sagittal or oblique sections or both also are useful and may be obtained directly or indirectly. Difficulty in patient positioning may preclude direct sagittal imaging, however. The use of intravenous contrast enhancement is not necessary as a routine technique unless a mass is identified or suspected. Where surgical resection or biopsy of a space-occupying lesion is contemplated, contrast enhancement can be valuable in assessing relative vascularity and aiding diagnostic specificity. It should be continually emphasized that CT is a powerful technology which, in orbital diagnosis, produces the highest yield when clinician and radiologist collaborate in the radiodiagnostic workup. The clinical information supplied by the referring ophthalmologist is used by the radiologist both in the selection of the appropriate techniques for investigation and in striving to achieve the most specific conclusion

  7. Proton computed tomography images with algebraic reconstruction

    Energy Technology Data Exchange (ETDEWEB)

    Bruzzi, M. [Physics and Astronomy Department, University of Florence, Florence (Italy); Civinini, C.; Scaringella, M. [INFN - Florence Division, Florence (Italy); Bonanno, D. [INFN - Catania Division, Catania (Italy); Brianzi, M. [INFN - Florence Division, Florence (Italy); Carpinelli, M. [INFN - Laboratori Nazionali del Sud, Catania (Italy); Chemistry and Pharmacy Department, University of Sassari, Sassari (Italy); Cirrone, G.A.P.; Cuttone, G. [INFN - Laboratori Nazionali del Sud, Catania (Italy); Presti, D. Lo [INFN - Catania Division, Catania (Italy); Physics and Astronomy Department, University of Catania, Catania (Italy); Maccioni, G. [INFN – Cagliari Division, Cagliari (Italy); Pallotta, S. [INFN - Florence Division, Florence (Italy); Department of Biomedical, Experimental and Clinical Sciences, University of Florence, Florence (Italy); SOD Fisica Medica, Azienda Ospedaliero-Universitaria Careggi, Firenze (Italy); Randazzo, N. [INFN - Catania Division, Catania (Italy); Romano, F. [INFN - Laboratori Nazionali del Sud, Catania (Italy); Sipala, V. [INFN - Laboratori Nazionali del Sud, Catania (Italy); Chemistry and Pharmacy Department, University of Sassari, Sassari (Italy); Talamonti, C. [INFN - Florence Division, Florence (Italy); Department of Biomedical, Experimental and Clinical Sciences, University of Florence, Florence (Italy); SOD Fisica Medica, Azienda Ospedaliero-Universitaria Careggi, Firenze (Italy); Vanzi, E. [Fisica Sanitaria, Azienda Ospedaliero-Universitaria Senese, Siena (Italy)

    2017-02-11

    A prototype of proton Computed Tomography (pCT) system for hadron-therapy has been manufactured and tested in a 175 MeV proton beam with a non-homogeneous phantom designed to simulate high-contrast material. BI-SART reconstruction algorithms have been implemented with GPU parallelism, taking into account of most likely paths of protons in matter. Reconstructed tomography images with density resolutions r.m.s. down to ~1% and spatial resolutions <1 mm, achieved within processing times of ~15′ for a 512×512 pixels image prove that this technique will be beneficial if used instead of X-CT in hadron-therapy.

  8. Multidetector computed tomography in the preoperative staging of gastric adenocarcinoma

    International Nuclear Information System (INIS)

    Barros, Ricardo Hoelz de Oliveira; Penachim, Thiago Jose; Martins, Daniel Lahan; Andreollo, Nelson Adami; Caserta, Nelson Marcio Gomes

    2015-01-01

    Objective: To evaluate the role of multidetector computed tomography in the preoperative investigation of tumor invasion depth and lymph node and metastatic involvement according to the TNM classification, in patients with gastric adenocarcinoma. Materials and Methods: Fifty-four patients with biopsy-confirmed gastric cancer underwent preoperative staging with 64-channel multidetector computed tomography. Two independent radiologists analyzed the images and classified the findings. Sensitivity, specificity, accuracy and overall accuracy were calculated for each observer. The interobserver agreement was also evaluated. Results: The accuracy in the classification of categories T ranged from 74% to 96% for observer 1 and from 80% to 92% for observer 2. The overall accuracy was 70% for both observers. The weighted kappa index was 0.75, consistent with a significant interobserver agreement. The accuracy in the classification of lymph node involvement (category N) ranged from 55% to 79% for observer 1 and from 73% to 82% for observer 2. The evaluation of metastatic involvement showed an overall accuracy of 89.6% for both observers. Conclusion: 64-channel multidetector computed tomography demonstrated clinically relevant accuracy in the preoperative staging of gastric adenocarcinoma as regards invasion depth (T category) and metastatic involvement (M category). (author)

  9. Multidetector computed tomography in the preoperative staging of gastric adenocarcinoma

    Directory of Open Access Journals (Sweden)

    Ricardo Hoelz de Oliveira Barros

    2015-04-01

    Full Text Available Objective: To evaluate the role of multidetector computed tomography in the preoperative investigation of tumor invasion depth and lymph node and metastatic involvement according to the TNM classification, in patients with gastric adenocarcinoma. Materials and Methods: Fifty-four patients with biopsy-confirmed gastric cancer underwent preoperative staging with 64-channel multidetector computed tomography. Two independent radiologists analyzed the images and classified the findings. Sensitivity, specificity, accuracy and overall accuracy were calculated for each observer. The interobserver agreement was also evaluated. Results: The accuracy in the classification of categories T ranged from 74% to 96% for observer 1 and from 80% to 92% for observer 2. The overall accuracy was 70% for both observers. The weighted kappa index was 0.75, consistent with a significant interobserver agreement. The accuracy in the classification of lymph node involvement (category N ranged from 55% to 79% for observer 1 and from 73% to 82% for observer 2. The evaluation of metastatic involvement showed an overall accuracy of 89.6% for both observers. Conclusion: 64-channel multidetector computed tomography demonstrated clinically relevant accuracy in the preoperative staging of gastric adenocarcinoma as regards invasion depth (T category and metastatic involvement (M category.

  10. Multidetector computed tomography in the preoperative staging of gastric adenocarcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Barros, Ricardo Hoelz de Oliveira; Penachim, Thiago Jose; Martins, Daniel Lahan; Andreollo, Nelson Adami; Caserta, Nelson Marcio Gomes, E-mail: rhobarros@hotmail.com [Universidade Estadual de Campinas (UNICAMP), Campinas, SP (Brazil)

    2015-03-15

    Objective: To evaluate the role of multidetector computed tomography in the preoperative investigation of tumor invasion depth and lymph node and metastatic involvement according to the TNM classification, in patients with gastric adenocarcinoma. Materials and Methods: Fifty-four patients with biopsy-confirmed gastric cancer underwent preoperative staging with 64-channel multidetector computed tomography. Two independent radiologists analyzed the images and classified the findings. Sensitivity, specificity, accuracy and overall accuracy were calculated for each observer. The interobserver agreement was also evaluated. Results: The accuracy in the classification of categories T ranged from 74% to 96% for observer 1 and from 80% to 92% for observer 2. The overall accuracy was 70% for both observers. The weighted kappa index was 0.75, consistent with a significant interobserver agreement. The accuracy in the classification of lymph node involvement (category N) ranged from 55% to 79% for observer 1 and from 73% to 82% for observer 2. The evaluation of metastatic involvement showed an overall accuracy of 89.6% for both observers. Conclusion: 64-channel multidetector computed tomography demonstrated clinically relevant accuracy in the preoperative staging of gastric adenocarcinoma as regards invasion depth (T category) and metastatic involvement (M category). (author)

  11. Computed tomography findings of pancreatic metastases from renal cell carcinoma

    International Nuclear Information System (INIS)

    Prando, Adilson

    2008-01-01

    Objective: To present computed tomography findings observed in four patients submitted to radical nephrectomy for renal cell carcinoma who developed pancreatic metastases afterwards. Materials and methods: The four patients underwent radical nephrectomy for stage Tz1 (n=2) and stage T3a (n=2) renal cell carcinoma. The mean interval between nephrectomy and detection of pancreatic metastases was eight years. Two asymptomatic patients presented with solitary pancreatic metastases (confined to the pancreas). Two symptomatic patients presented with single and multiple pancreatic metastases, both with tumor recurrence in the contralateral kidney. Results: Computed tomography studies demonstrated pancreatic metastases as solitary (n=2), single (n=1) or multiple (n=1) hypervascular lesions. Partial pancreatectomy was performed in two patients with solitary pancreatic metastases and both are free of disease at four and two years after surgery. Conclusion: Pancreatic metastases from renal cell carcinoma are rare and can occur many years after the primary tumor presentation. Multiple pancreatic metastases and pancreatic metastases associated with tumor recurrence in the contralateral kidney are uncommon. Usually, on computed tomography images pancreatic metastases are visualized as solitary hypervascular lesions, simulating isletcell tumors. Surgical management should be considered for patients with solitary pancreatic lesions. (author)

  12. Computed tomography findings of pancreatic metastases from renal cell carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Prando, Adilson [Hospital Vera Cruz, Campinas, SP (Brazil). Dept. of Radiology and Imaging Diagnosis]. E-mail: adilson.prando@gmail.com

    2008-07-15

    Objective: To present computed tomography findings observed in four patients submitted to radical nephrectomy for renal cell carcinoma who developed pancreatic metastases afterwards. Materials and methods: The four patients underwent radical nephrectomy for stage Tz1 (n=2) and stage T3a (n=2) renal cell carcinoma. The mean interval between nephrectomy and detection of pancreatic metastases was eight years. Two asymptomatic patients presented with solitary pancreatic metastases (confined to the pancreas). Two symptomatic patients presented with single and multiple pancreatic metastases, both with tumor recurrence in the contralateral kidney. Results: Computed tomography studies demonstrated pancreatic metastases as solitary (n=2), single (n=1) or multiple (n=1) hypervascular lesions. Partial pancreatectomy was performed in two patients with solitary pancreatic metastases and both are free of disease at four and two years after surgery. Conclusion: Pancreatic metastases from renal cell carcinoma are rare and can occur many years after the primary tumor presentation. Multiple pancreatic metastases and pancreatic metastases associated with tumor recurrence in the contralateral kidney are uncommon. Usually, on computed tomography images pancreatic metastases are visualized as solitary hypervascular lesions, simulating isletcell tumors. Surgical management should be considered for patients with solitary pancreatic lesions. (author)

  13. Three-dimensional computed tomography angiography of coronary artery bypass graft with electron beam tomography

    Energy Technology Data Exchange (ETDEWEB)

    Hoshi, Toshiko; Yamauchi, Tatsuo; Kanauchi, Tetsu; Konno, Miyuki; Imai, Kamon; Suwa, Jiro; Onoguchi, Katsuhisa; Hashimoto, Kazuhiro; Horie, Toshinobu [Saitama Cardiovascular and Respiratory Center, Konan (Japan)

    2001-10-01

    Assessment of coronary artery bypass graft patency by three-dimensional reconstructed computed tomography angiography (3D-CTA) derived from electrocardiography-gated contrast-enhanced electron beam tomography (EBT) was evaluated. Thirty-nine patients with 99 grafts (45 arterial grafts and 54 venous grafts) underwent 3D-CTA and selective coronary angiography within a 3-week interval. 3D-CTA images of the coronary bypass grafts were compared with the coronary angiography images used as the control. 3D-CTA defined 42 of 44 arterial grafts as patent (sensitivity: 95%), all 47 venous grafts as patent (sensitivity: 100%) and all 7 venous grafts as occlusive (specificity: 100%). The overall sensitivity and specificity were 98% and 88%, respectively. 3D-CTA is an useful noninvasive technique with adequate sensitivity and specificity to assess coronary artery bypass graft patency. (author)

  14. Role of Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography in Diagnostic Evaluation of Carcinoma Urinary Bladder: Comparison with Computed Tomography

    International Nuclear Information System (INIS)

    Chakraborty, Dhritiman; Mittal, Bhagwant Rai; Kashyap, Raghava; Mete, Utham Kumar; Narang, Vikram; Das, Ashim; Bhattacharya, Anish; Khandelwal, Niranjan; Mandal, Arup K.

    2014-01-01

    Bladder carcinoma is the most frequent tumor of the urinary tract and accounts 7% of all malignancies in men and 2% of all malignancies in women. This retrospective study was carried out to assess the diagnostic utility of F18-fludeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) in the imaging evaluation of bladder carcinoma. Seventy-seven consecutive patients diagnosed to have carcinoma urinary bladder referred for F18-FDG PET/CT were included in this study. Thirty-four patients were for initial staging after transurethral biopsy and remaining 43 patients were for restaging. All patients also underwent CT scan of the abdomen and pelvis. PET/CT findings were correlated with diagnostic CT scan and histopathological findings. In 30 of the 34 patients for initial staging, both PET/CT and CT confirmed the primary lesion in the bladder. Histopathology report was available in 23 patients. Lymph nodes FDG uptake reported to be metastatic in 10/23 patients while CT detected lymph node metastasis in 12 patients. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and accuracy have been calculated to be 87.5%, 80%, 70%, 92%, 82% for PET/CT and 66%, 57%, 50%, 72%, 60% for CT respectively. PET/CT detected metastatic disease in 8 patients whereas CT detected in 4 patients. Of the 43 patients for restaging, local recurrence was detected in 24 patients on both PET/CT and CT. Histopathology report was available in 17 patients. Sensitivity, specificity, PPV, NPV and accuracy were 85%, 60%, 60%, 85%, 70% for PET/CT and 80%, 50%, 40%, 85%, 58% for CT respectively. Nineteen patients were detected to have metastatic disease by PET/CT, whereas CT detected metastases in 11 patients. F-18 FDG PET/CT is a very useful modality in pre-operative staging and monitoring after surgery, chemotherapy or radiotherapy of patients with carcinoma urinary bladder

  15. Cone beam computed tomography in endodontic

    Energy Technology Data Exchange (ETDEWEB)

    Durack, Conor; Patel, Shanon, E-mail: conordurack1@hotmail.com [Unit of Endodontology, Department of Conservative Dentistry, King' s College London, London (United Kingdom)

    2012-07-01

    Cone beam computed tomography (CBCT) is a contemporary, radiological imaging system designed specifically for use on the maxillofacial skeleton. The system overcomes many of the limitations of conventional radiography by producing undistorted, three-dimensional images of the area under examination. These properties make this form of imaging particularly suitable for use in endodontic. The clinician can obtain an enhanced appreciation of the anatomy being assessed, leading to an improvement in the detection of endodontic disease and resulting in more effective treatment planning. In addition, CBCT operates with a significantly lower effective radiation dose when compared with conventional computed tomography (CT). The purpose of this paper is to review the current literature relating to the limitations and potential applications of CBCT in endodontic practice. (author)

  16. Possibilities of computer tomography in multiple sclerosis

    International Nuclear Information System (INIS)

    Vymazal, J.; Bauer, J.

    1983-01-01

    Computer tomography was performed in 41 patients with multiple sclerosis, the average age of patients being 40.8 years. Native examinations were made of 17 patients, examinations with contrast medium of 19, both methods were used in the examination of 5 patients. In 26 patients, i.e. in almost two-thirds, cerebral atrophy was found, in 11 of a severe type. In 9 patients atrophy affected only the hemispheres, in 16 also the stem and cerebellum. The stem and cerebellum only were affected in 1 patient. Hypodense foci were found in 21 patients, i.e. more than half of those examined. In 9 there were multiple foci. In most of the 19 examined patients the hypodense changes were in the hemispheres and only in 2 in the cerebellum and brain stem. No hyperdense changes were detected. The value and possibilities are discussed of examinations by computer tomography multiple sclerosis. (author)

  17. Soil structure changes evaluated with computed tomography

    International Nuclear Information System (INIS)

    Pires, Luiz Fernando

    2010-01-01

    The objective of this work was to evaluate in millimetric scale changes in soil bulk density and porosity, using the gamma-ray computed tomography in soil samples with disturbed structure due to wetting and drying (W-D) cycles. Soil samples with 98.1 cm 3 were sieved using a 2 mm mesh and homogeneously packed in PVC cylinders. Soil samples were submitted to 1, 2, and 3 W-D cycles. Control samples were not submitted to W-D cycles. After repetitions of W-D cycles, soil sample porosity decreased and soil layers became denser. Computed tomography allowed a continuous analysis of soil bulk density and also soil porosity along millimetric (0.08 cm) layers, what cannot be provided by traditional methods used in soil physics. (author)

  18. Computed Tomography Biomarkers of Vulnerable Coronary Plaques

    Directory of Open Access Journals (Sweden)

    Nyulas Tiberiu

    2016-12-01

    Full Text Available An unstable plaque has a high risk of thrombosis and at the same time for a fast progression of the stenosis degree. Also, “high-risk plaque” and “thrombosis-prone plaque” are used as synonym terms for characterization of a vulnerable plaque. The imaging biomarkers for vulnerable coronary plaques are considered to be spotty calcifications, active remodeling, low-density atheroma and the presence of a ring-like attenuation pattern, also known as the napkin-ring sign. Computed cardiac tomography can determine the plaque composition by assessing the plaque density, which is measured in Hounsfield units (HU. The aim of this manuscript was to provide an update about the most frequently used biomarkers of vulnerability in a vulnerable plaque with the help of computed cardiac tomography.

  19. Basic principle of cone beam computed tomography

    International Nuclear Information System (INIS)

    Choi, Yong Suk; Kim, Gyu Tae; Hwang, Eui Hwan

    2006-01-01

    The use of computed tomography for dental procedures has increased recently. Cone beam computed tomography(CBCT) systems have been designed for imaging hard tissues of the dentomaxillofacial region. CBCT is capable of providing high resolution in images of high diagnostic quality. This technology allows for 3-dimensional representation of the dentomaxillofacial skeleton with minimal distortion, but at lower equipment cost, simpler image acquisition and lower patient dose. Because this technology produces images with isotropic sub-millimeter spatial resolution, it is ideally suited for dedicated dentomaxillofacial imaging. In this paper, we provide a brief overview of cone beam scanning technology and compare it with the fan beam scanning used in conventional CT and the basic principles of currently available CBCT systems

  20. Xenon as an adjunct in computed tomography

    International Nuclear Information System (INIS)

    Kendall, B.E.; Radue, E.W.; Zilkha, E.; Loh, L.

    1979-01-01

    Nonradioactive xenon was used for enhancement in computed tomography in a series of 18 patients requiring general anesthesia. The method and results are described. The properties of xenon are radically different from those of intravenous iodides, and the enhancement patterns demonstrate different aspects of both normal and abnormal tissues. In our limited experience, it has been of value in those isodense and low attenuation lesions that have not enhanced after intravenous Conray. (orig.) 891 MG/orig. 892 MB [de

  1. Computed tomography of the eye and orbit

    International Nuclear Information System (INIS)

    Hammerschlag, S.B.; Hesselink, J.R.; Weber, A.L.

    1982-01-01

    This book is the product of the evolution of computed tomography (CT) into subspecialization and the need for one source of information for the busy radiologist. The authors have succeeded in providing a readable overview of orbital CT as well as a reference book. The book is divided into seven major catagories of pathology (Neurofibromatosis, Primary Orbital Neoplasms, Secondary and Metastic Tumors of the Orbit, Vascular Disorders, Inflammatory Disease, Occular Lesions, and Trauma) after separate discussions of anatomy and technique

  2. Cranial computed tomography of the neurofibromatosis

    International Nuclear Information System (INIS)

    Fukuda, Teruo; Inoue, Yuichi; Shibakiri, Ippei

    1981-01-01

    The computed tomography (CT) was performed in 10 cases of neurofibromatosis. The CT scan showed the abnormal findings in 8 cases out of 10. Skull lesions were noted in 3 cases and intracranial tumors were found in 5 among which multiple neoplasms were seen in 3. Although reported cases were not large enough in number, the incidence and variety of the tumors were similar to others reported before CT era. (author)

  3. Computed tomography in gastrointestinal stromal tumors

    International Nuclear Information System (INIS)

    Ghanem, Nadir; Altehoefer, Carsten; Winterer, Jan; Schaefer, Oliver; Springer, Oliver; Kotter, Elmar; Langer, Mathias; Furtwaengler, Alex

    2003-01-01

    The aim of this study was to define the imaging characteristics of primary and recurrent gastrointestinal stromal tumors (GIST) in computed tomography with respect to the tumor size. Computed tomography was performed in 35 patients with histologically confirmed gastrointestinal stromal tumors and analyzed retrospectively by two experienced and independent radiologist. The following morphologic tumor characteristics of primary (n=20) and (n=16) recurrent tumors were evaluated according to tumor size, shape, homogeneity, density compared with liver, contrast enhancement, presence of calcifications, ulcerations, fistula or distant metastases and the anatomical relationship to the intestinal wall, and the infiltration of adjacent visceral organs. Small GIST ( 5-10 cm) demonstrated an irregular shape, inhomogeneous density on unenhanced and contrast-enhanced images, a combined intra- and extraluminal tumor growth with aggressive findings, and infiltration of adjacent organs in 9 primary diagnosed and 2 recurrent tumors. Large GIST (>10 cm), which were observed in 8 primary tumors and 11 recurrent tumors, showed an irregular margin with inhomogeneous density and aggressive findings, and were characterized by signs of malignancy such as distant and peritoneal metastases. Small recurrent tumors had a similar appearance as compared with large primary tumors. Computed tomography gives additional information with respect to the relationship of gastrointestinal stromal tumor to the gastrointestinal wall and surrounding organs, and it detects distant metastasis. Primary and recurrent GIST demonstrate characteristic CT imaging features which are related to tumor size. Aggressive findings and signs of malignancy are found in larger tumors and in recurrent disease. Computed tomography is useful in detection and characterization of primary and recurrent tumors with regard to tumor growth pattern, tumor size, and varied appearances of gastrointestinal stromal tumors, and indirectly

  4. Encapsulating peritonitis: computed tomography and surgical correlation

    Energy Technology Data Exchange (ETDEWEB)

    Kadow, Juliana Santos; Fingerhut, Carla Jeronimo Peres; Fernandes, Vinicius de Barros; Coradazzi, Klaus Rizk Stuhr; Silva, Lucas Marciel Soares; Penachim, Thiago Jose, E-mail: vinicius.barros.fernandes@gmail.com [Pontificia Universidade Catolica de Campinas (PUC-Campinas), Campinas, SP (Brazil). Hospital e Maternidade Celso Pierro

    2014-07-15

    Sclerosing encapsulating peritonitis is a rare and frequently severe entity characterized by total or partial involvement of small bowel loops by a membrane of fibrous tissue. The disease presents with nonspecific clinical features of intestinal obstruction, requiring precise imaging diagnosis to guide the treatment. The present report emphasizes the importance of computed tomography in the diagnosis of this condition and its confirmation by surgical correlation. (author)

  5. Computed tomography of the calcaneus: normal anatomy

    International Nuclear Information System (INIS)

    Heger, L.; Wulff, K.

    1985-01-01

    The normal sectional anatomy of the calcaneus was studied as the background for interpretation of computed tomography (CT) of fractures. Multiplanar CT examination of the normal calcaneus was obtained, and sections were matched with a simplified anatomic model. Sectional anatomy in the four most important planes is described. This facilitates three-dimensional understanding of the calcaneus from sections and interpretation of CT sections obtained in any atypical plane

  6. Computed tomography in opportunistic lung infections

    International Nuclear Information System (INIS)

    Hartelius, H.

    1988-01-01

    Chest radiography in two teenage boys, one with Wiscott-Aldrich's syndrome and one with acute lymphatic leucemia in remission showed increased interstitial pattern. In both computed tomography (CT) of the lungs showed heavy interstitial pneumonia, rather different in appearance but in both cases equal to the CT findings in opportunistic lung infections known from immunoincompetent patients with for instance pneumocystis carinii and/or cytomegalo virus infections. In both patients the CT findings led to lung biopsy establishing the etiologic agent. (orig.)

  7. Physics and instrumentation of emission computed tomography

    International Nuclear Information System (INIS)

    Links, J.M.

    1986-01-01

    Transverse emission computed tomography can be divided into two distinct classes: single photon emission computed tomography (SPECT) and positron emission tomography (PET). SPECT is usually accomplished with specially-adapted scintillation cameras, although dedicated SPECT scanners are available. The special SPECT cameras are standard cameras which are mounted on gantries that allow 360 degree rotation around the long axis of the head or body. The camera stops at a number of angles around the body (usually 64-128), acquiring a ''projection'' image at each stop. The data from these projections are used to reconstruct transverse images with a standard ''filtered back-projection'' algorithm, identical to that used in transmission CT. Because the scintillation camera acquires two-dimensional images, a simple 360 degree rotation around the patient results in the acquisition of data for a number of contiguous transverse slices. These slices, once reconstructed, can be ''stacked'' in computer memory, and orthogonal coronal and sagittal slices produced. Additionally, reorienting algorithms allow the generation of slices that are oblique to the long axis of the body

  8. Inter laboratory comparison on Industrial Computed Tomography

    DEFF Research Database (Denmark)

    Angel, Jais Andreas Breusch; De Chiffre, Leonardo; Larsen, Erik

    The ‘CIA-CT comparison - Inter laboratory comparison on industrial Computed Tomography” is organized by DTU Department of Mechanical Engineering within the Danish project “Centre for Industrial Application of CT scanning - CIA-CT”. The project is co-financed by the Danish Ministry of Science......, Technology and Innovation. The comparison aims to collect information about measurement performance in state-of the-art industrial CT (Computed Tomography) scanning. Since CT scanning has entered the field of manufacturing and coordinate metrology, evaluation of uncertainty of measurement with assessment...

  9. Positron emission tomography/computed tomography imaging and rheumatoid arthritis.

    Science.gov (United States)

    Wang, Shi-Cun; Xie, Qiang; Lv, Wei-Fu

    2014-03-01

    Rheumatoid arthritis (RA) is a phenotypically heterogeneous, chronic, destructive inflammatory disease of the synovial joints. A number of imaging tools are currently available for evaluation of inflammatory conditions. By targeting the upgraded glucose uptake of infiltrating granulocytes and tissue macrophages, positron emission tomography/computed tomography with fluorine-18 fluorodeoxyglucose ((18) F-FDG PET/CT) is available to delineate inflammation with high sensitivity. Recently, several studies have indicated that FDG uptake in affected joints reflects the disease activity of RA. In addition, usage of FDG PET for the sensitive detection and monitoring of the response to treatment has been reported. Combined FDG PET/CT enables the detailed assessment of disease in large joints throughout the whole body. These unique capabilities of FDG PET/CT imaging are also able to detect RA-complicated diseases. Therefore, PET/CT has become an excellent ancillary tool to assess disease activity and prognosis in RA. © 2014 Asia Pacific League of Associations for Rheumatology and Wiley Publishing Asia Pty Ltd.

  10. Therapy response evaluation with positron emission tomography-computed tomography.

    Science.gov (United States)

    Segall, George M

    2010-12-01

    Positron emission tomography-computed tomography with F-18-fluorodeoxyglucose is widely used for evaluation of therapy response in patients with solid tumors but has not been as readily adopted in clinical trials because of the variability of acquisition and processing protocols and the absence of universal response criteria. Criteria proposed for clinical trials are difficult to apply in clinical practice, and gestalt impression is probably accurate in individual patients, especially with respect to the presence of progressive disease and complete response. Semiquantitative methods of determining tissue glucose metabolism, such as standard uptake value, can be a useful descriptor for levels of tissue glucose metabolism and changes in response to therapy if technical quality control measures are carefully maintained. The terms partial response, complete response, and progressive disease are best used in clinical trials in which the terms have specific meanings and precise definitions. In clinical practice, it may be better to use descriptive terminology agreed upon by imaging physicians and clinicians in their own practice. Copyright © 2010. Published by Elsevier Inc.

  11. Computed tomography to quantify tooth abrasion

    Science.gov (United States)

    Kofmehl, Lukas; Schulz, Georg; Deyhle, Hans; Filippi, Andreas; Hotz, Gerhard; Berndt-Dagassan, Dorothea; Kramis, Simon; Beckmann, Felix; Müller, Bert

    2010-09-01

    Cone-beam computed tomography, also termed digital volume tomography, has become a standard technique in dentistry, allowing for fast 3D jaw imaging including denture at moderate spatial resolution. More detailed X-ray images of restricted volumes for post-mortem studies in dental anthropology are obtained by means of micro computed tomography. The present study evaluates the impact of the pipe smoking wear on teeth morphology comparing the abraded tooth with its contra-lateral counterpart. A set of 60 teeth, loose or anchored in the jaw, from 12 dentitions have been analyzed. After the two contra-lateral teeth were scanned, one dataset has been mirrored before the two datasets were registered using affine and rigid registration algorithms. Rigid registration provides three translational and three rotational parameters to maximize the overlap of two rigid bodies. For the affine registration, three scaling factors are incorporated. Within the present investigation, affine and rigid registrations yield comparable values. The restriction to the six parameters of the rigid registration is not a limitation. The differences in size and shape between the tooth and its contra-lateral counterpart generally exhibit only a few percent in the non-abraded volume, validating that the contralateral tooth is a reasonable approximation to quantify, for example, the volume loss as the result of long-term clay pipe smoking. Therefore, this approach allows quantifying the impact of the pipe abrasion on the internal tooth morphology including root canal, dentin, and enamel volumes.

  12. Fluorescence Computed Tomography with Polychromatic Source Data

    Science.gov (United States)

    Miqueles, Eduardo; De Pierro, Alvaro R.

    2013-02-01

    Fluorescence computed tomography is a synchrotron imaging technique aiming at reconstructing the fluorescence emission within a sample object. For a polychromatic source hitting the object, the amount of fluorescence detected is defined by a linear equation. For the monochromatic case, the operator is a Generalized Attenuated Radon Transform (GART). The main goal is to reconstruct the density function, given the sinogram data and the weight function. An eficient iterative algorithm for the inversion of the GART was presented recently by the authors. This inversion can only be performed if the weight function is previously known, which means that μ = μ(·, epsilon) and λ are also known. For monochromatic XFCT (acronym for x-rays fluorescence computed tomography), the determination of λ is a dificult task, and we have considered the approximation λ ≈ μ, which is valid for low energies ranging from 3Kev to 10Kev. So, for solving our problem, the first step is to find μ given the polychromatic sinogram. There are different approaches for this in the literature. Recently, an elegant and efficient method for solving this problem was introduced, using a fixed point algorithm. Opposite to this, where μ(·, epsilon) needs to be computed for all epsilon in E, we claim that the integral of μ(·, epsilon) for all epsilon has a physical meaning and provides a good aproximation for the solution. Also we present fast algorithm for computations.

  13. Concrescence: assessment of case by periapical radiography, cone beam computed tomography and micro-computed tomography.

    Science.gov (United States)

    Neves, Frederico Sampaio; Rovaris, Karla; Oliveira, Matheus Lima; Novaes, Pedro Duarte; de Freitas, Deborah Queiroz

    2014-04-01

    The aim of this article was to describe imaging aspects of concrescence analyzed by three imaging modalities. A second molar joined together with a third molar was imaged using digital periapical radiography, cone beam computed tomography (CBCT) and micro-computed tomography (Micro-CT). On periapical radiograph, the mesial root of the third molar is superimposed on the distal root of the second molar. On CBCT images, a large cementum union between bulbous roots was detected, confirming the diagnosis of concrescence. On micro-CT images, the cementum union appeared limited to the apical third of the roots. In conclusion, both computed tomography modalities allowed for the diagnosis of concrescence. However, only micro-CT provided the real extension of the cementum union.

  14. Mathematics in computed tomography and related techniques

    International Nuclear Information System (INIS)

    Sawicka, B.

    1992-01-01

    The mathematical basis of computed tomography (CT) was formulated in 1917 by Radon. His theorem states that the 2-D function f(x,y) can be determined at all points from a complete set of its line integrals. Modern methods of image reconstruction include three approaches: algebraic reconstruction techniques with simultaneous iterative reconstruction or simultaneous algebraic reconstruction; convolution back projection; and the Fourier transform method. There is no one best approach. Because the experimental data do not strictly satisfy theoretical models, a number of effects have to be taken into account; in particular, the problems of beam geometry, finite beam dimensions and distribution, beam scattering, and the radiation source spectrum. Tomography with truncated data is of interest, employing mathematical approximations to compensate for the unmeasured projection data. Mathematical techniques in image processing and data analysis are also extensively used. 13 refs

  15. Positron Computed Tomography: Current State, Clinical Results and Future Trends

    Science.gov (United States)

    Schelbert, H. R.; Phelps, M. E.; Kuhl, D. E.

    1980-09-01

    An overview is presented of positron computed tomography: its advantages over single photon emission tomography, its use in metabolic studies of the heart and chemical investigation of the brain, and future trends. (ACR)

  16. Positron computed tomography: current state, clinical results and future trends

    International Nuclear Information System (INIS)

    Schelbert, H.R.; Phelps, M.E.; Kuhl, D.E.

    1980-01-01

    An overview is presented of positron computed tomography: its advantages over single photon emission tomography, its use in metabolic studies of the heart and chemical investigation of the brain, and future trends

  17. RELIABILITY OF POSITRON EMISSION TOMOGRAPHY-COMPUTED TOMOGRAPHY IN EVALUATION OF TESTICULAR CARCINOMA PATIENTS.

    Science.gov (United States)

    Nikoletić, Katarina; Mihailović, Jasna; Matovina, Emil; Žeravica, Radmila; Srbovan, Dolores

    2015-01-01

    The study was aimed at assessing the reliability of 18F-fluorodeoxyglucose positron emission tomography-computed tomography scan in evaluation of testicular carcinoma patients. The study sample consisted of 26 scans performed in 23 patients with testicular carcinoma. According to the pathohistological finding, 14 patients had seminomas, 7 had nonseminomas and 2 patients had a mixed histological type. In 17 patients, the initial treatment was orchiectomy+chemotherapy, 2 patients had orchiectomy+chemotherapy+retroperitoneal lymph node dissection, 3 patients had orchiectomy only and one patient was treated with chemotherapy only. Abnormal computed tomography was the main cause for the oncologist to refer the patient to positron emission tomography-computed tomography scan (in 19 scans), magnetic resonance imaging abnormalities in 1 scan, high level oftumor markers in 3 and 3 scans were perforned for follow-up. Positron emission tomography-computed tomography imaging results were compared with histological results, other imaging modalities or the clinical follow-up of the patients. Positron emission tomography-computed tomography scans were positive in 6 and negative in 20 patients. In two patients, positron emission tomography-computed tomography was false positive. There were 20 negative positron emission omography-computed tomography scans perforned in 18 patients, one patient was lost for data analysis. Clinically stable disease was confirmed in 18 follow-up scans performed in 16 patients. The values of sensitivty, specificity, accuracy, and positive- and negative predictive value were 60%, 95%, 75%, 88% and 90.5%, respectively. A hgh negative predictive value obtained in our study (90.5%) suggests that there is a small possibility for a patient to have future relapse after normal positron emission tomography-computed tomography study. However, since the sensitivity and positive predictive value of the study ire rather low, there are limitations of positive

  18. Use of computed tomography and positron emission tomography/computed tomography for staging of local extent in patients with malignant pleural mesothelioma.

    Science.gov (United States)

    Frauenfelder, Thomas; Kestenholz, Peter; Hunziker, Roger; Nguyen, Thi Dan Linh; Fries, Martina; Veit-Haibach, Patrick; Husmann, Lars; Stahel, Rolf; Weder, Walter; Opitz, Isabelle

    2015-01-01

    The objective of this study was to determine the diagnostic value of computed tomography (CT) and positron emission tomography (PET)/CT for staging of malignant pleural mesothelioma (MPM) in patients undergoing induction chemotherapy. Sixty-two patients (median age, 61 years; female: n = 9) with proven MPM underwent CT after induction chemotherapy. Of these, 28 underwent additional PET/CT. Extrapleural pneumonectomy was performed for pathological TNM staging. Clinical TNM stage was assessed by 3 independent readers. Relative and absolute underestimation and overestimation were compared with pathological tumor stage. Sensitivity, specificity, and accuracy for differentiation between stages T2 and T3 were assessed. Interobserver agreement between the readers was analyzed (κ). Positron emission tomography/CT and CT underestimated T stage in up to 30% of the cases. Positron emission tomography/CT had a higher accuracy for tumor extent compared with CT (PET/CT: 0.92; CT: 0.84). The accuracy for nodal staging was higher for CT than for PET/CT (PET/CT: 0.78; CT: 0.87). Concerning International Mesothelioma Interest Group classification, PET/CT improved the accuracy of preoperative staging compared with CT (PET/CT: 0.91; CT: 0.82). Interobserver agreement was moderate for CT (0.48-0.62) and good for PET/CT (0.64-0.83) for T staging. For nodal staging, interobserver agreement was fair to moderate for CT and good for PET/CT (CT: 0.37-0.51; PET/CT: 0.73-0.76). Positron emission tomography/CT is more accurate and has a lower interobserver variability for clinical intrathoracic staging of MPM compared with CT. Nevertheless PET/CT underestimated tumor stage in a substantial number of cases, showing the need for a more accurate imaging technology or approach.

  19. The use of computed tomography to assess asthma severity.

    Science.gov (United States)

    Mitsunobu, Fumihiro; Tanizaki, Yoshiro

    2005-02-01

    Chronic inflammation in asthma can also lead to airway remodeling, which contributes to airway narrowing. It may be possible to assess and quantify the extent of airway remodeling in vivo using computed tomography. This review examines recent developments in the evaluation of asthma severity using computed tomography, and the effect of treatment assessed by computed tomography. Asthma patients have thicker airways on computed tomography scans than do healthy control individuals, and the degree of thickening is related to the severity of disease, airflow obstruction, and airway reactivity. Recent studies have indicated that patients with severe asthma and irreversible airflow obstruction had longer disease duration, a greater inflammatory process and more airway abnormalities, assessed by high-resolution computed tomography, suggestive of airway remodeling. Other studies have shown that high-resolution computed tomography lung density correlates with airflow limitation and lung volume (but not with lung transfer factor), and also correlates with patient age and severity of asthma. More recently, two publications demonstrated the effect of treatment on airway wall thickness and lung density assessed by computed tomography in patients with asthma. High-resolution computed tomography is one of the most useful tools for imaging airways and parenchyma. Computed tomography scanning may be useful in determining which patients might benefit from more or less treatment. With additional advances in technology, it is likely that quantitative assessment by computed tomography will ultimately be a valuable tool for the study and treatment of chronic airway diseases.

  20. Brain Computed Tomography Compared with Facial 3-Dimensional Computed Tomography for Diagnosis of Facial Fractures.

    Science.gov (United States)

    Lee, Sun Hwa; Yun, Seong Jong; Ryu, Seokyong; Choi, Seoung Won; Kim, Hye Jin; Kang, Tae Kyug; Oh, Sung Chan; Cho, Suk Jin

    2017-05-01

    To compare the detection of facial fractures and radiation dose between brain computed tomography (CT) and facial 3-dimensional (3D) CT in pediatric patients who have experienced a trauma. Four hundred pediatric patients who experienced a trauma and underwent immediate brain CT and facial 3D CT between January 2016 and June 2016 were included in this retrospective study. Two reviewers independently analyzed and determined the presence of the facial fractures of 8 anatomic regions based on brain CT and facial 3D CT over a 1-week interval. Suggested treatment decisions for facial fractures seen on brain CT and facial 3D CT were evaluated by one physician. The facial 3D CT scans, interpreted by a senior radiologist, were considered as the reference standard. Diagnostic performance, radiation dose, and interobserver agreement of the CT scans were evaluated. Brain CT showed a high sensitivity (94.1%-96.5%), high specificity (99.7%-100%), and high accuracy (98.8%-99.0%) in both reviewers, and performed as well as did facial 3D CT (P ≥ .25). The suggested treatment decision was not different between the brain CT and facial 3D CT findings. The agreements between the reference standard and the reviewers, and between reviewers 1 and 2 were excellent (k = 0.946-0.993). The mean effective radiation doses used in brain CT (3.6 mSv) were significantly lower than those in brain CT with facial 3D CT (5.5 mSv) (P Brain CT showed acceptable diagnostic performance and can be used as the first-line imaging tool in the workup of pediatric patients with suspected facial fractures. Copyright © 2017 Elsevier Inc. All rights reserved.

  1. Clinical value of whole body fluorine-18 fluorodeoxyglucose positron emission tomography/computed tomography in the detection of metastatic bladder cancer.

    Science.gov (United States)

    Yang, Zhongyi; Pan, Lingling; Cheng, Jingyi; Hu, Silong; Xu, Junyan; Ye, Dingwei; Zhang, Yingjian

    2012-07-01

    To investigate the value of whole-body fluorine-18 2-fluoro-2-deoxy-D-glucose positron emission tomography/computed tomography for the detection of metastatic bladder cancer. From December 2006 to August 2010, 60 bladder cancer patients (median age 60.5 years old, range 32-96) underwent whole body positron emission tomography/computed tomography positron emission tomography/computed tomography. The diagnostic accuracy was assessed by performing both organ-based and patient-based analyses. Identified lesions were further studied by biopsy or clinically followed for at least 6 months. One hundred and thirty-four suspicious lesions were identified. Among them, 4 primary cancers (2 pancreatic cancers, 1 colonic and 1 nasopharyngeal cancer) were incidentally detected, and the patients could be treated on time. For the remaining 130 lesions, positron emission tomography/computed tomography detected 118 true positive lesions (sensitivity = 95.9%). On the patient-based analysis, the overall sensitivity and specificity resulted to be 87.1% and 89.7%, respectively. There was no difference of sensitivity and specificity in patients with or without adjuvant treatment in terms of detection of metastatic sites by positron emission tomography/computed tomography. Compared with conventional imaging modality, positron emission tomography/computed tomography correctly changed the management in 15 patients (25.0%). Positron emission tomography/computed tomography has excellent sensitivity and specificity in the detection of metastatic bladder cancer and it provides additional diagnostic information compared to standard imaging techniques. © 2012 The Japanese Urological Association.

  2. Clinical value of whole body fluorine-18 fluorodeoxyglucose positron emission tomography/computed tomography in the detection of metastatic bladder cancer

    International Nuclear Information System (INIS)

    Yang Zhongyi; Pan Lingling; Cheng Jingyi; Hu Silong; Xu Junyan; Zhang Yingjian; Ye Dingwei

    2012-01-01

    The objective of this study was to investigate the value of whole-body fluorine-18 2-fluoro-2-deoxy-D-glucose positron emission tomography/computed tomography for the detection of metastatic bladder cancer. From December 2006 to August 2010, 60 bladder cancer patients (median age 60.5 years old, range 32-96) underwent whole body positron emission tomography/computed tomography positron emission tomography/computed tomography. The diagnostic accuracy was assessed by performing both organ-based and patient-based analyses. Identified lesions were further studied by biopsy or clinically followed for at least 6 months. One hundred and thirty-four suspicious lesions were identified. Among them, 4 primary cancers (2 pancreatic cancers, 1 colonic and 1 nasopharyngeal cancer) were incidentally detected, and the patients could be treated on time. For the remaining 130 lesions, positron emission tomography/computed tomography detected 118 true positive lesions (sensitivity=95.9%). On the patient-based analysis, the overall sensitivity and specificity resulted to be 87.1% and 89.7%, respectively. There was no difference of sensitivity and specificity in patients with or without adjuvant treatment in terms of detection of metastatic sites by positron emission tomography/computed tomography. Compared with conventional imaging modality, positron emission tomography/computed tomography correctly changed the management in 15 patients (25.0%). Positron emission tomography/computed tomography has excellent sensitivity and specificity in the detection of metastatic bladder cancer and it provides additional diagnostic information compared to standard imaging techniques. (author)

  3. Unusual causes of obstructive jaundice. Computed tomography

    International Nuclear Information System (INIS)

    Rodriguez, E.; Pombo, F.; Cao, I.; Fernandez, R.; Riba da, M.

    1998-01-01

    The purpose of this study is to present selected computed tomography (CT) images showing unusual causes of obstructive jaundice. We reviewed retrospectively the Ct findings of obstructive jaundice in 227 patients. The most common causes of biliary obstruction were adenocarcinoma of the pancreatic head (n=77) and cholangiocarcinoma (n=65). In 13 cases (5.7%), the etiology of obstructive jaundice was unusual or exceptional: tuberculous adenitis (n=3), obstruction of afferent loop (n=2)signet ring cell adenocarcinoma (n=3); in duodenum, gallbladder and papilla of Water), Mirizzi syndrome (n=1), adenocarcinoma of the hepatic flexure (n=1), choledochal cyst (n=1) and pancreatic lymphoma (n=1). (Author) 13 refs

  4. Enlarged retrorectal space - indication for computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Krestin, G.P.; Steinbrich, W.; Beyer, D.

    1985-03-01

    The reasonable use of computed tomography in the diagnosis of an enlarged retrorectal space was analysed in 92 cases. CT is useful in differentiation of a pathologically enlarged retrorectal space without mucosal lesions of the rectum. It enables the separation between tumorous masses, proliferation of connective tissue (in retrorectal fibrosis or inflammatory disease) and pelvic lipomatosis. If simultaneous mucosal involvement in barium enema or rectoscopy - especially in rectal carcinoma or recurrent carcinoma of the rectum - is found, CT may show the perirectal extension of tumorous masses and thus help to clarify local operability.

  5. 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

  6. Contrast media on abdominal computed tomography

    International Nuclear Information System (INIS)

    Skalpe, I.O.; Oestensen, H.M.

    1984-01-01

    Abdominal computed tomography was performed in 55 patients before and after intravenous injection of 60 ml of a non-ionic (iohexol) or an ionic (metrizoate) contrast medium. The adverse effects were recorded and a series of measurements of attenuation values before and after the contrast medium injection was performed in the aorta and in hepatic and renal parenchyma. Only minor adverse effects were seen with both contrast media, but iohexol was clearly better tolerated than metrizoate. No difference in the enhancement properties was found between the two contrast media. (orig.)

  7. Multidetector Computed Tomography in Acute Joint Fractures

    International Nuclear Information System (INIS)

    Haapamaeki, V.V.; Kiuru, M.J.; Mustonen, A.O.; Koskinen, S.K.

    2005-01-01

    Conventional radiography plays an essential diagnostic role in the primary evaluation of acute joint trauma. In complex fractures, however, computed tomography (CT) is an imaging modality often used second to radiography. As a result of technical breakthroughs in the field, multidetector CT (MDCT) allows faster imaging and better temporal, spatial, and contrast resolution compared with conventional single-slice spiral CT. MDCT with multiplanar reformation is helpful in disclosing fracture patterns, particularly in complex joint fractures, where they reveal occult fractures and show the exact number of fracture components and their degree of displacement

  8. Sparse Image Reconstruction in Computed Tomography

    DEFF Research Database (Denmark)

    Jørgensen, Jakob Sauer

    In recent years, increased focus on the potentially harmful effects of x-ray computed tomography (CT) scans, such as radiation-induced cancer, has motivated research on new low-dose imaging techniques. Sparse image reconstruction methods, as studied for instance in the field of compressed sensing...... and limitations of sparse reconstruction methods in CT, in particular in a quantitative sense. For example, relations between image properties such as contrast, structure and sparsity, tolerable noise levels, suficient sampling levels, the choice of sparse reconstruction formulation and the achievable image...

  9. Computed tomography features of small bowel volvulus

    International Nuclear Information System (INIS)

    Loh, Y.H.; Dunn, G.D.

    2000-01-01

    Small bowel volvulus is a cause of acute abdomen and commonly occurs in neonates and young infants. Although it is rare in adults in the Western world,' it is a relatively common surgical emergency in the Middle East, India and Central Africa. It is associated with a mortality rate of 10-67% and, hence, it is important to make an early diagnosis to expedite surgical intervention. Computed tomography has become an important imaging modality in diagnosis and a number of signs have been recognized in a handful of documented case reports. We describe a case of small bowel volvulus that illustrates these important CT signs. Copyright (1999) Blackwell Science Pty Ltd

  10. Application of protons to computer tomography

    International Nuclear Information System (INIS)

    Hanson, K.M.; Bradbury, J.N.; Cannon, T.M.; Hutson, R.L.; Laubacher, D.B.; Macek, R.; Paciotti, M.A.; Taylor, C.A.

    1977-01-01

    It was demonstrated that the application of protons to computed tomography can result in a significant dose advantage relative to x rays. Thus, at the same dose as is delivered by contemporary commercial x-ray scanners, a proton scanner could produce reconstructions with a factor of 2 or more improvement in density resolution. Whether such an improvement can result in significantly better diagnoses of human disease is an open question which can only be answered by the implementation of a proton scanner in a clinical situation

  11. Computed tomography appearances of sclerosing encapsulating peritonitis

    Energy Technology Data Exchange (ETDEWEB)

    George, C. [Department of Radiology, Hull Royal Infirmary, Hull (United Kingdom)]. E-mail: cheriangeorge@hotmail.com; Al-Zwae, K. [Department of Radiology, Hull Royal Infirmary, Hull (United Kingdom); Nair, S. [Department of Radiology, Hull Royal Infirmary, Hull (United Kingdom); Cast, J.E.I. [Department of Radiology, Hull Royal Infirmary, Hull (United Kingdom)

    2007-08-15

    Sclerosing encapsulating peritonitis (SEP) is a serious complication of peritoneal dialysis (PD) characterized by thickened peritoneal membranes, which lead to decreased ultra-filtration and intestinal obstruction. Its early clinical features are nonspecific, and it is often diagnosed late following laparotomy and peritoneal biopsy, when the patient develops small bowel obstruction, which can be a life-threatening complication. However, this is changing with increasing awareness of computed tomography (CT) findings in SEP. CT can yield an early, non-invasive diagnosis that may improve patient outcome. We present a review of the CT appearances of SEP.

  12. Computed tomography in neuronal ceroid lipofuscinosis

    International Nuclear Information System (INIS)

    Valavanis, A.; Schubiger, O.; Hayek, J.; Friede, R.L

    1981-01-01

    The computed tomography (CT) findings in a verified case of neutronal ceroid lipofuscinosis (NCL) are presented. CT revealed diffuse and severe cerebral atrophy, reflected by generalized subarachnoid space enlargement and symmetric ventricular dilatation. There was no evidence of abnormalities of the white matter. The CT features in our case of NCL correspond perfectly with the neuropathologic changes of the disease mentioned in the literature. Furthermore, CT is of considerable help in differentiating between those inherited metabolic brain diseases characterized primarily by white matter involvement and those presenting predominantly with changes of grey matter. (orig.) [de

  13. [Positron emission tomography/computed tomography for lung cancer staging].

    Science.gov (United States)

    Ladrón de Guevara H, David; Furnaro L, Francisca; Yévenes A, Sebastián; Clavero R, José Miguel; Lazo P, David; Rodríguez D, Patricio; Piottante B, Antonio; Pefaur D, Raúl; Pardo B, Claudio

    2015-01-01

    PET/CT (Positron Emission Tomography/Computed Tomography) is widely used in nodal and metastatic staging of lung cancer patients. To analyze PET/CT detection of metastatic disease in patients with lung cancer. We reviewed retrospectively F18Fluorodeoxyglucose PET/CT scans performed between December 2008 and December 2013. We selected 143 patients aged 30 to 92 years (63% males) with confirmed lung cancer referred for staging, with no previous treatment. We reviewed whole body PET/CT and brain magnetic resonance images. SUVmax (Standardized Uptake Value maximum) of primary pulmonary lesion, hilar/mediastinal nodes, and distant metastases were calculated. Histological types encountered were adenocarcinoma in 55%, squamous-cell in 15%, small-cell in 8%, large-cell in 6% and adeno-squamous in 2%. In 22 cases (15%) histology was not available. Nodal involvement was observed in 60% of patients (44% hilar and 48% mediastinal). Skip metastases (mediastinal involvement without hilum involvement) were encountered in 17% of cases, and were significantly more common among high uptake lung tumors (p < 0.01). Best SUVmax cut-off for node involvement was 4.4 for hilum and 4.0 for mediastinum (sensibility: 86.4%, specificity: 99.8%). Sixty six patients (46.2%) showed distant metastases on PET/CT. The most common metastases were osseous in 22%, adrenal in 16%, hepatic in14%, pulmonary in 14% and cerebral in 12%. PET/CT detected a second unexpected synchronic cancer in eight patients (6%). PET/CT is accurate for nodal staging using an uptake index as SUVmax. Distant metastases are common, especially in bone, adrenal glands and liver.

  14. Radiocarpal Injuries: Cone Beam Computed Tomography Arthrography, Magnetic Resonance Arthrography, and Arthroscopic Correlation among 21 Patients.

    Science.gov (United States)

    Suojärvi, N; Haapamäki, V; Lindfors, N; Koskinen, S K

    2017-06-01

    Patients with acute or chronic wrist pain often undergo wrist arthroscopy for evaluation of chondral and ligamentous abnormalities. The purpose of this study was to compare findings of wrist arthroscopy with cone beam computed tomography arthrography and magnetic resonance arthrography. Altogether, 21 patients with wrist pain underwent cone beam computed tomography arthrography, magnetic resonance arthrography, and wrist arthroscopy. Chondral surfaces of the scaphoid, lunate, and radius facing the scaphoid and lunate were evaluated. The scapholunate ligament, the lunotriquetral ligament, and the triangular fibrocartilage complex were classified as either intact or torn. Sensitivity, specificity, positive and negative predictive values, and accuracy with 95% confidence intervals were assessed. For chondral lesions (n = 10), cone beam computed tomography arthrograms showed slightly higher specificity than magnetic resonance arthrography. The sensitivity of cone beam computed tomography arthrography was also better for these lesions, except for those on the chondral surface of the lunate. For triangular fibrocartilage complex injuries (n = 9), cone beam computed tomography arthrography showed a better specificity and sensitivity than magnetic resonance arthrography. For ligamentous injuries (n = 6), cone beam computed tomography arthrograms were more sensitive, but less specific than magnetic resonance arthrography images. However, the number of lesions was very small and the 95% confidence intervals are overlapping. Cone beam computed tomography is an emerging imaging modality that offers several advantages over computed tomography and magnetic resonance imaging. Its usefulness particularly in ligamentous injuries should be further explored in a larger study. Cone beam computed tomography arthrography seems to offer similar sensitivity, specificity, and accuracy compared to magnetic resonance arthrography and therefore serves as a valuable option in

  15. Fused Entropy Algorithm in Optical Computed Tomography

    Directory of Open Access Journals (Sweden)

    Xiong Wan

    2014-02-01

    Full Text Available In most applications of optical computed tomography (OpCT, limited-view problems are often encountered, which can be solved to a certain extent with typical OpCT reconstructive algorithms. The concept of entropy first emerged in information theory has been introduced into OpCT algorithms, such as maximum entropy (ME algorithms and cross entropy (CE algorithms, which have demonstrated their superiority over traditional OpCT algorithms, yet have their own limitations. A fused entropy (FE algorithm, which follows an optimized criterion combining self-adaptively ME with CE, is proposed and investigated by comparisons with ME, CE and some traditional OpCT algorithms. Reconstructed results of several physical models show this FE algorithm has a good convergence and can achieve better precision than other algorithms, which verifies the feasibility of FE as an approach of optimizing computation, not only for OpCT, but also for other image processing applications.

  16. Speeding up image reconstruction in computed tomography

    CERN Multimedia

    CERN. Geneva

    2018-01-01

    Computed tomography (CT) is a technique for imaging cross-sections of an object using X-ray measurements taken from different angles. In last decades a significant progress has happened there: today advanced algorithms allow fast image reconstruction and obtaining high-quality images even with missing or dirty data, modern detectors provide high resolution without increasing radiation dose, and high-performance multi-core computing devices are there to help us solving such tasks even faster. I will start with CT basics, then briefly present existing classes of reconstruction algorithms and their differences. After that I will proceed to employing distinctive architectural features of modern multi-core devices (CPUs and GPUs) and popular program interfaces (OpenMP, MPI, CUDA, OpenCL) for developing effective parallel realizations of image reconstruction algorithms. Decreasing full reconstruction time from long hours up to minutes or even seconds has a revolutionary impact in diagnostic medicine and industria...

  17. Traumatic lung lesions: computed tomography findings

    International Nuclear Information System (INIS)

    Melo, Alessandro Severo Alves de; Moreira, Luiza Beatriz Melo; Marchiori, Edson

    2003-01-01

    Traumatic lesions of the lung are common findings in patients with thoracic trauma. These lesions are increasingly diagnosed using computed tomography, mostly due to the fast acquisition time helical techniques that allow evaluation of critically ill patients and an efficient therapeutic management. The authors studied 150 patients with thoracic trauma submitted to computed tomography that demonstrated lung contusions, atelectasis, lacerations and hematomas. Lung contusions were the most frequent lesions appearing as consolidation or ground-glass attenuation areas. Atelectasis, in subsegmentar and compressive patterns, were the second most common lesions observed. Lacerations appeared as consolidations with air or liquid level. Lung hematomas, characterized by round opacities, were the most rare lung lesions seen in only five cases. In this study, blunt thoracic trauma accounted for the majority of 120 cases whereas penetrating trauma occurred in 30 cases. The causes of blunt trauma in de crescent order of frequency were motor vehicle accidents, pedestrian hit by car, falls, motorcycle accidents and trashing. Penetrating traumas were caused by bullets or knives. (author)

  18. Abdominal alterations in disseminated paracoccidioidomycosis: computed tomography findings

    OpenAIRE

    Marli Batista Fernandes Vermelho; Ademir Silva Correia; Tânia Cibele de Almeida Michailowsky; Elizete Kazumi Kuniyoshi Suzart; Aline Santos Ibanês; Lanamar Aparecida Almeida; Zarifa Khoury; Mário Flores Barba

    2015-01-01

    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...

  19. A Clinical Evaluation Of Cone Beam Computed Tomography

    Science.gov (United States)

    2016-06-01

    reliability of multidetector computed tomography and cone beam computed tomography in the assessment of dental implant site dimensions. Dentomaxillofacial...A CLINICAL EVALUATION OF CONE BEAM COMPUTED TOMOGRAPHY by Bryan James Behm, D.D.S. Lieutenant, Dental Corps United States Navy A thesis...submitted to the Faculty of the Endodontic Graduate Program Naval Postgraduate Dental School Uniformed Services University of the Health Sciences in

  20. Assesment of Acetabulum Fractures by Multidetector Computed Tomography

    International Nuclear Information System (INIS)

    Pinzon, Mariana; Pardo Patricia; Quintana, Jose

    2008-01-01

    Acetabular fractures were best classified by using multiplanar computed tomography, allowing the orthopedist a better surgical planning. This paper reviews different acetabulum fractures, traumatic mechanisms and classification.

  1. Value of postmortem computed tomography in comparison to autopsy

    International Nuclear Information System (INIS)

    Paperno, S.; Krug, B.; Lackner, L.; Riepert, T.; Rothschild, M.A.; Schultes, A.; Staak, M.

    2005-01-01

    Purpose: to assess the diagnostic value of postmortem computed tomography (CT) in comparison to autopsy. Materials and methods: twenty-seven cadavers were examined by sequential cranial CT and helical CT through the neck, thorax and abdomen and subsequently underwent an autopsy with histomorphologic examination of the pathologic specimens. The findings of CT, autopsy and histology were registered and compared by three radiologists and one specialist for forensic medicine, using a data entry form. Results: in 19 of 27 cases, the findings explaining the cause of death were concordant for CT and autopsy. Intracranial, intraspinal and intracardiac gas accumulations (n = 12) were registered by CT alone. The detection of skull fractures was equal for both methods (n = 3). CT showed diagnostic problems in the assessment of pneumonic infiltrations (n = 16) and pulmonary edema (n = 21). Conclusion: CT is a useful and complementary method to autopsy. (orig.)

  2. Diagnostic reference level of computed tomography (CT) in Japan.

    Science.gov (United States)

    Fukushima, Yasuhiro; Tsushima, Yoshito; Takei, Hiroyuki; Taketomi-Takahashi, Ayako; Otake, Hidenori; Endo, Keigo

    2012-08-01

    Optimisation of computed tomography (CT) parameters is important in avoiding excess radiation exposure. The aim of this study is to establish the diagnostic reference levels (DRL) of CT in Japan by using dose-length product (DLP). Datasheets were sent to all hospitals/clinics which had CT scanner(s) in Gunma prefecture. Data were obtained for all patients who underwent CT during a single month (June 2010), and the distributions of DLP were evaluated for eight anatomical regions and five patient age groups. The DRL was defined as the 25th and 75th percentiles of DLP. Datasheets were collected from 80 of 192 hospitals/clinics (26 090 patients). DLP for head CT of paediatric patients tended to be higher in Japan compared with DRLs of paediatric head CTs reported from the EU or Syria. Although this study was performed with limited samples, DLP for adult patients were at comparable levels for all anatomical regions.

  3. Radiological management of blunt polytrauma with computed tomography and angiography: an integrated approach

    International Nuclear Information System (INIS)

    Kurdziel, J.C.; Dondelinger, R.F.; Hemmer, M.

    1987-01-01

    107 polytraumatized patients, who had experienced blunt trauma have been worked up at admission with computed tomography of the thorax, abdomen and pelvis following computed tomography study of the brain: significant lesions were revealed in 98 (90%) patients. 79 (74%) patients showed trauma to the thorax, in 69 (64%) patients abdominal or pelvic trauma was evidenced. No false positive diagnosis was established. 5 traumatic findings were missed. Emergency angiography was indicated in 3 (3%) patients, following computed tomography examination. 3 other trauma patients were submitted directly to angiography without computed tomography examination during the time period this study was completed. Embolization was carried out in 5/6 patients. No thoracotomy was needed. 13 (12%) patients underwent laparotomy following computed tomography. Overall mortality during hospital stay was 14% (15/107). No patient died from visceral bleeding. Conservative management of blunt polytrauma patients can be advocated in almost 90% of visceral lesions. Computed tomography coupled with angiography and embolization represent an adequate integrated approach to the management of blunt polytrauma patients

  4. Lung Cancer in Patients With Tuberculous Fibrothorax and Empyema: Computed Tomography and 18F-Fluorodeoxyglucose Positron Emission Tomography Findings.

    Science.gov (United States)

    Xu, Hai; Koo, Hyun Jung; Lee, Han Na; Lim, Soyeoun; Lee, Jae Wook; Choi, Chang-Min; Kim, Mi Young

    The aim of this study was to describe the characteristics of lung cancers in patients with tuberculous fibrothorax or empyema. We retrospectively evaluated 138 consecutive patients with a diagnosis of lung cancer combined with fibrothorax (n = 127) or empyema (n = 11) from January 2005 to May 2015. All patients underwent computed tomography, and 105 underwent F-fluorodeoxyglucose positron emission tomography. Clinical, pathologic, and computed tomography characteristics and maximum standardized uptake values on positron emission tomography of 76 cancers ipsilateral to the fibrothorax or empyema (group 1) were compared with those of 62 contralateral cancers (group 2). The median age at diagnosis of patients was 70 years, with a male-to-female ratio of 8.9:1. The most common type was squamous cell carcinoma (41.3%) followed by adenocarcinoma (39.1%). Most were in the peripheral lung (70.3%), and half abutted the pleura. The median maximum standardized uptake value was 8.9. Tumors in group 1 were larger (median, 48.5 vs 42.8 mm, P = 0.036) and more advanced (T3 or T4) (P = 0.014) than those in group 2. Lung cancers ipsilateral to tuberculous fibrothorax or empyema presented larger and advanced T stages, and the diagnosis could be delayed. The most common type cancer was squamous cell carcinoma.

  5. Computed tomography in the evaluation of diverticulitis

    International Nuclear Information System (INIS)

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

    1984-01-01

    Computed tomography (CT) was performed in 43 cases of colonic diverticulitis and compared with the contrast-enema examination (CE) in 37 patients. Findings on CT included inflammation of the pericolic fat in 98% of cases, diverticula in 84%, thickening of the colon wall in 70%, a pericolic abscess in 35%, peritonitis in 16%, a fistula in 14%, colon obstruction in 12%, and intramural sinus tracts in 9%. In addition to detecting ureteral and bladder involvement and distant abscess formation, CT was preferable for demonstrating the extent of pericolic inflammation, which was underestimated with CE in 41% of patients. Differential diagnosis of the CT findings is discussed. The authors indicate that CT should be the initial procedure in patients with suspected diverticulitis, particularly when CE is contraindicated

  6. Computed tomography findings in convergent strabismus fixus

    International Nuclear Information System (INIS)

    Ohta, Michitaka; Iwashige, Hiroyasu; Hayashi, Takao; Maruo, Toshio

    1995-01-01

    X-ray computed tomography (CT) of the eyeball and orbit revealed the cause of eye movement disorder in convergent strabismus fixus. The findings suggest that the disease can be diagnosed and treated at an early stage. Twelve cases of progressive esotropia with high myopia and 20 cases with normal visual acuity served as subjects in this study. The CT slice was parallel to the German horizontal plane, and the lens and medial and lateral rectus muscles were scanned. The average axial length of the affected eyes was significantly longer than in normal eyes. In progressive esotropia, the characteristic CT findings are an elongated eyeball, mechanical contact between the eyeball and lateral wall of the orbit, and a downward displacement of the lateral rectus muscle. Thus, it is reasonable to conclude that eye movement disorder in convergent strabismus fixus results from weakness of the lateral rectus muscle which has been displaced downward due to compression of the eyeball against the orbital wall. (author)

  7. Computed tomography of atresia auris congenita

    International Nuclear Information System (INIS)

    Kiuchi, Sousuke; Koide, Fujio

    1983-01-01

    Computed tomography was performed in 9 patients with atresia auris congenita. In this study, scans were done in axial or coronal projection with the CT/T body scanner. The external auditory canals were involved in varying degrees from mild narrowing to complete atresia. In partial atresia, CT scanning demonstrated the patency of the canal, and also showed the cardrum as a clearly defined soft tissue. Simulatenously, the associated middle ear anomalies were well demonstrated. One of the most common deformities of the ossicular chains was fusion of the malleus and incus. In some cases, these ossicles were dislocated, and occasionally were fixed to the atresia plate or attic wall. Other variations of the temporal bone could be assumed. We concluded that CT is the technique of choice to evaluate patients with atresia auris congenita. (author)

  8. Teleradiology for emergency cranial computed tomography

    International Nuclear Information System (INIS)

    Stranzinger, E.; Treumann, T.C.; Dreier, D.; Allgayer, B.

    2003-01-01

    Purpose: We report our experience with the teleradiologic service provided by a center hospital (CH) for emergency cranial computed tomography (CCT) in two regional hospitals (RH) during a 12-month period. The clinical and economic impact of teleradiology will be discussed as well as the acceptance by the clinicians of the regional hospitals. Material and Methods: In 2001, 213 CT-scans in 202 patients were performed and reported using teleradiology. Teleradiologic and final medical diagnosis were analysed by the medical reports. The transferral of the patients to a CH and their further treatment were checked. The referring physicians in the RH were questionnaired about the teleradiological support. Results: 18 (9%) patients had to be urgently transferred to a CH based on the CT findings in the teleradiological reports. 24 patients (11%) were transferred to a center hospital during further treatment. 80% of patients were treated in the RH. (orig.) [de

  9. Computer tomography of intracranial tumours and hematomas

    International Nuclear Information System (INIS)

    Tans, J.T.J.

    1978-01-01

    The value of computed tomography (CT) for the diagnosis of intracranial tumors and hematomas was investigated in a retrospective study comprising 220 patients. All C.T.scans are reviewed and described in detail. To assess the diagnostic accuracy, the original interpretation of the C.T.scans was compared with that of conventional neuroradiological and neurophysiological examinations. The aspect on C.T. of the various types of tumors and hematomas proved to vary widely and specific features were seldom seen. This holds particularly for the malignant tumors. Benign tumors such as meningeomas, adenomas and neurilemmomas showed a rather easily identifiable and almost identical picture of the C.T.scan, and diagnosis had to be based mainly on differences in localization. The hematomas, with the exception of the older intracerebral ones, showed the most characteristic C.T.abnormalities. (Auth.)

  10. Technological Evolution on Computed Tomography and Radioprotection

    International Nuclear Information System (INIS)

    Leite, Bruno Barros; Ribeiro, Nuno Carrilho

    2006-01-01

    Computed Tomography (CT) has been available since the 70s and has experienced a dramatic technical evolution. Multi-detector technology is our current standard, offering capabilities unthinkable only a decade ago. Yet, we must nor forget the ionizing nature of CT's scanning energy (X-rays). It represents the most important cause of medical-associated radiation exposure to the general public, with a trend to increase. It is compulsory to intervene with the objective of dose reduction, following ALARA policies. Currently there are some technical advances that allow dose reduction, without sacrificing diagnostic image capabilities. However, human intervention is also essential. We must keep investment on education so that CT exams are don when they are really useful in clinical decision. Alternative techniques should also be considered. Image quality must not be searched disregarding the biological effects of radiation. Generally, it is possible to obtain clinically acceptable images with lower dose protocols. (author)

  11. Quality assurance of computed tomography (CT) scanners

    International Nuclear Information System (INIS)

    Sankaran, A.; Sanu, K.K. . Email : a_sankaran@vsnl.com

    2004-01-01

    This article reviews the present status of research work and development of various test objects, phantoms and detector/instrumentation systems for quality assurance (QA) of computed tomography (CT) scanners, carried out in advanced countries, with emphasis on similar work done in this research centre. CT scanner is a complex equipment and routine quality control procedures are essential to the maintenance of image quality with optimum patient dose. Image quality can be ensured only through correlation between prospective monitoring of system components and tests of overall performance with standard phantoms. CT examinations contribute a large share to the population dose in advanced countries. The unique dosimetry problems in CT necessitate special techniques. This article describes a comprehensive kit developed indigenously for the following QA and type approval tests as well as for research studies on image quality/dosimetry on CT scanners

  12. Computed Tomography in the Modern Slaughterhouse

    DEFF Research Database (Denmark)

    Mosbech, Thomas Hammershaimb

    of technology. Recently, the use of X-ray computed tomography (CT) coupled with methods from image analysis has been introduced as a powerful means to optimise production, by providing detailed information on the raw materials. This thesis covers two aspects of the application of CT in the modern abattoir......The Danish pig meat industry has been seeing a growing international competition in the past years. In the quest to maintain both competitive prices and high product standards in spite of the higher Danish factor costs, a substantial effort is being put into innovation, research and development...... the yield of the Danish pig meat industry. An introduction of efficient online CT will especially open a vast number of possibilities for optimising the production....

  13. Mouse brain imaging using photoacoustic computed tomography

    Science.gov (United States)

    Lou, Yang; Xia, Jun; Wang, Lihong V.

    2014-03-01

    Photoacoustic computed tomography (PACT) provides structural and functional information when used in small animal brain imaging. Acoustic distortion caused by bone structures largely limits the deep brain image quality. In our work, we present ex vivo PACT images of freshly excised mouse brain, intending that can serve as a gold standard for future PACT in vivo studies on small animal brain imaging. Our results show that structures such as the striatum, hippocampus, ventricles, and cerebellum can be clearly di erentiated. An artery feature called the Circle of Willis, located at the bottom of the brain, can also be seen. These results indicate that if acoustic distortion can be accurately accounted for, PACT should be able to image the entire mouse brain with rich structural information.

  14. Practical techniques for pediatric computed tomography

    International Nuclear Information System (INIS)

    Fitz, C.R.; Harwood-Nash, D.C.; Kirks, D.R.; Kaufman, R.A.; Berger, P.E.; Kuhn, J.P.; Siegel, M.J.

    1983-01-01

    Dr. Donald Kirks has assembled this section on Practical Techniques for Pediatric Computed Tomography. The material is based on a presentation in the Special Interest session at the 25th Annual Meeting of the Society for Pediatric Radiology in New Orleans, Louisiana, USA in 1982. Meticulous attention to detail and technique is required to ensure an optimal CT examination. CT techniques specifically applicable to infants and children have not been disseminated in the radiology literature and in this respect it may rightly be observed that ''the child is not a small adult''. What follows is a ''cookbook'' prepared by seven participants and it is printed in Pediatric Radiology, in outline form, as a statement of individual preferences for pediatric CT techniques. This outline gives concise explanation of techniques and permits prompt dissemination of information. (orig.)

  15. Data processing device for computed tomography system

    International Nuclear Information System (INIS)

    Nakayama, N.; Ito, Y.; Iwata, K.; Nishihara, E.; Shibayama, S.

    1984-01-01

    A data processing device applied to a computed tomography system which examines a living body utilizing radiation of X-rays is disclosed. The X-rays which have penetrated the living body are converted into electric signals in a detecting section. The electric signals are acquired and converted from an analog form into a digital form in a data acquisition section, and then supplied to a matrix data-generating section included in the data processing device. By this matrix data-generating section are generated matrix data which correspond to a plurality of projection data. These matrix data are supplied to a partial sum-producing section. The partial sums respectively corresponding to groups of the matrix data are calculated in this partial sum-producing section and then supplied to an accumulation section. In this accumulation section, the final value corresponding to the total sum of the matrix data is calculated, whereby the calculation for image reconstruction is performed

  16. Analysis of airways in computed tomography

    DEFF Research Database (Denmark)

    Petersen, Jens

    Chronic Obstructive Pulmonary Disease (COPD) is major cause of death and disability world-wide. It affects lung function through destruction of lung tissue known as emphysema and inflammation of airways, leading to thickened airway walls and narrowed airway lumen. Computed Tomography (CT) imaging...... have become the standard with which to assess emphysema extent but airway abnormalities have so far been more challenging to quantify. Automated methods for analysis are indispensable as the visible airway tree in a CT scan can include several hundreds of individual branches. However, automation...... the Danish Lung Cancer Screening Trial. This includes methods for extracting airway surfaces from the images and ways of achieving comparable measurements in airway branches through matching and anatomical labelling. The methods were used to study effects of differences in inspiration level at the time...

  17. Quality assessment of clinical computed tomography

    Science.gov (United States)

    Berndt, Dorothea; Luckow, Marlen; Lambrecht, J. Thomas; Beckmann, Felix; Müller, Bert

    2008-08-01

    Three-dimensional images are vital for the diagnosis in dentistry and cranio-maxillofacial surgery. Artifacts caused by highly absorbing components such as metallic implants, however, limit the value of the tomograms. The dominant artifacts observed are blowout and streaks. Investigating the artifacts generated by metallic implants in a pig jaw, the data acquisition for the patients in dentistry should be optimized in a quantitative manner. A freshly explanted pig jaw including related soft-tissues served as a model system. Images were recorded varying the accelerating voltage and the beam current. The comparison with multi-slice and micro computed tomography (CT) helps to validate the approach with the dental CT system (3D-Accuitomo, Morita, Japan). The data are rigidly registered to comparatively quantify their quality. The micro CT data provide a reasonable standard for quantitative data assessment of clinical CT.

  18. Advanced proton imaging in computed tomography

    CERN Document Server

    Mattiazzo, S; Giubilato, P; Pantano, D; Pozzobon, N; Snoeys, W; Wyss, J

    2015-01-01

    In recent years the use of hadrons for cancer radiation treatment has grown in importance, and many facilities are currently operational or under construction worldwide. To fully exploit the therapeutic advantages offered by hadron therapy, precise body imaging for accurate beam delivery is decisive. Proton computed tomography (pCT) scanners, currently in their R&D phase, provide the ultimate 3D imaging for hadrons treatment guidance. A key component of a pCT scanner is the detector used to track the protons, which has great impact on the scanner performances and ultimately limits its maximum speed. In this article, a novel proton-tracking detector was presented that would have higher scanning speed, better spatial resolution and lower material budget with respect to present state-of-the-art detectors, leading to enhanced performances. This advancement in performances is achieved by employing the very latest development in monolithic active pixel detectors (to build high granularity, low material budget, ...

  19. Analysis of mesenteric thickening on computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Takano, Hideyuki; Sekiya, Tohru; Miyakawa, Kunihisa; Ozaki, Masatoki; Katsuyama, Naofumi; Nakano, Masao (University of the Ryukyu, Okinawa (Japan). School of Medicine)

    1990-12-01

    Computed tomography (CT) provides noninvasive information in the evaluation of abnormalities of the gastrointestinal tract by direct imaging of the bowel wall and adjacent mesentery. Several prior studies have discussed the variable CT appearances of mesenteric abnormalities, such as lymphoma, metastasis, inflammatory disease and edema. Although mesenteric thickening was mentioned in these studies, no study has provided a detailed analysis of the CT appearance of the thickened mesentery. Two characteristic types of mesenteric thickening were identified in 47 patients. Type I is 'intramesenteric thickening', which was noted in 25 patients with vascular obstruction, inflammatory disease and edema. Type II is 'mesenteric surface thickening', which was noted in 22 patients with peritonitis carcinomatosa, peritoneal mesothelioma, tuberculous peritonitis and pseudomyxoma peritoneai. An understanding of these two types of mesenteric diseases is important in the identification of mesenteric pathology. (author).

  20. Analysis of mesenteric thickening on computed tomography

    International Nuclear Information System (INIS)

    Takano, Hideyuki; Sekiya, Tohru; Miyakawa, Kunihisa; Ozaki, Masatoki; Katsuyama, Naofumi; Nakano, Masao

    1990-01-01

    Computed tomography (CT) provides noninvasive information in the evaluation of abnormalities of the gastrointestinal tract by direct imaging of the bowel wall and adjacent mesentery. Several prior studies have discussed the variable CT appearances of mesenteric abnormalities, such as lymphoma, metastasis, inflammatory disease and edema. Although mesenteric thickening was mentioned in these studies, no study has provided a detailed analysis of the CT appearance of the thickened mesentery. Two characteristic types of mesenteric thickening were identified in 47 patients. Type I is 'intramesenteric thickening', which was noted in 25 patients with vascular obstruction, inflammatory disease and edema. Type II is 'mesenteric surface thickening', which was noted in 22 patients with peritonitis carcinomatosa, peritoneal mesothelioma, tuberculous peritonitis and pseudomyxoma peritoneai. An understanding of these two types of mesenteric diseases is important in the identification of mesenteric pathology. (author)

  1. Neutron stimulated emission computed tomography: Background corrections

    International Nuclear Information System (INIS)

    Floyd, Carey E.; Sharma, Amy C.; Bender, Janelle E.; Kapadia, Anuj J.; Xia, Jessie Q.; Harrawood, Brian P.; Tourassi, Georgia D.; Lo, Joseph Y.; Kiser, Matthew R.; Crowell, Alexander S.; Pedroni, Ronald S.; Macri, Robert A.; Tajima, Shigeyuki; Howell, Calvin R.

    2007-01-01

    Neutron stimulated emission computed tomography (NSECT) is an imaging technique that provides an in-vivo tomographic spectroscopic image of the distribution of elements in a body. To achieve this, a neutron beam illuminates the body. Nuclei in the body along the path of the beam are stimulated by inelastic scattering of the neutrons in the beam and emit characteristic gamma photons whose unique energy identifies the element. The emitted gammas are collected in a spectrometer and form a projection intensity for each spectral line at the projection orientation of the neutron beam. Rotating and translating either the body or the beam will allow a tomographic projection set to be acquired. Images are reconstructed to represent the spatial distribution of elements in the body. Critical to this process is the appropriate removal of background gamma events from the spectrum. Here we demonstrate the equivalence of two background correction techniques and discuss the appropriate application of each

  2. A computed tomography study of Alzheimer's disease

    International Nuclear Information System (INIS)

    Arai, H.; Kobayashi, K.; Juntendo Univ. School of Medicine, Tokyo; Ikeda, Y.; Nagao, Y.; Ogihara, R.; Kosaka, K.; Psychiatric Research Inst. of Tokyo

    1983-01-01

    Computed tomography (CT) was used to study cerebral atrophy in 18 patients with clinically diagnosed Alzheimer's disease of presenile type and in 14 healthy age-matched subjects as controls. Using the computerized planimetric method, Subarachnoid Space Volume Index and Ventricle Volume Index were calculated as the measure of cortical atrophy and ventricular dilatation respectively. From the results the following conclusions were drawn: 1. The cerebral atrophy in Alzheimer patients could be attributable to the disease processes rather than to physiological aging of the brain. 2. The degree of atrophy increases in parallel with the progress of the clinical stage, and the cortical atrophy is already apparent at an early stage, whereas the ventricular dilatation becomes pronounced at later stages. 3. CT could be one of the most useful clinical tests available for the diagnosis of Alzheimer's disease. (orig.) [de

  3. Computed Tomography findings in Fournier's gangrene

    International Nuclear Information System (INIS)

    Isusi, M.; Campo, M.; Oleaga, L.; Grande, J.; Grande, D.

    2000-01-01

    To assess the utility of computed tomography (CT) as an imaging technique in the diagnosis and determination of the extension of Fournier's gangrene (FG). We report the cases of six patients who had been clinically diagnosed as having FG, CT, enhanced by oral and intravenous contrast media, was performed in all the patients. All six patients presented soft tissue masses and gas in the scrotal region, which were also detected in the perineal region in five. In two patients, the gas extended toward anterior abdominal wall and in one of them, it also observed in anterior and posterior para renal space. The major predisposing factors were diabetes and alcoholism and the most common triggering factor was urologic disease. CT confirms the existence of FG and aids in assessing its extension and, in some cases, in identifying the underlying cause. (Author) 15 refs

  4. Antrum approach planning for removal of impacted tooth using cone-beam computed tomography.

    Science.gov (United States)

    de Mattos, Allex Morelli Heiderich; Queiroz, Christiano Sampaio; Santos, Pablo Leal Teixeira; de Oliviera, Adriana Borges; Oliveira, Camila; Campos, Paulo Sérgio Flores

    2012-01-01

    Due to the great number of structures in the maxillofacial region, cone-beam computed tomography (CBCT) is an important procedure in presurgical planning for removal of impacted teeth. Most of the information provided by this imaging technique cannot be visualized in conventional radiographs. In addition, CBCT reduces patient exposure to radiation in comparison with helical computed tomography and provides dental practitioners with easy access. We report the clinical case of a patient who underwent a surgical procedure for removal of an impacted maxillary premolar. CBCT-assisted presurgical treatment was used, enabling a more conservative surgical access, a less traumatic and less time consuming procedure than conventional surgical intervention.

  5. Nano-Computed Tomography: Technique and Applications.

    Science.gov (United States)

    Kampschulte, M; Langheinirch, A C; Sender, J; Litzlbauer, H D; Althöhn, U; Schwab, J D; Alejandre-Lafont, E; Martels, G; Krombach, G A

    2016-02-01

    Nano-computed tomography (nano-CT) is an emerging, high-resolution cross-sectional imaging technique and represents a technical advancement of the established micro-CT technology. Based on the application of a transmission target X-ray tube, the focal spot size can be decreased down to diameters less than 400 nanometers (nm). Together with specific detectors and examination protocols, a superior spatial resolution up to 400 nm (10 % MTF) can be achieved, thereby exceeding the resolution capacity of typical micro-CT systems. The technical concept of nano-CT imaging as well as the basics of specimen preparation are demonstrated exemplarily. Characteristics of atherosclerotic plaques (intraplaque hemorrhage and calcifications) in a murine model of atherosclerosis (ApoE (-/-)/LDLR(-/-) double knockout mouse) are demonstrated in the context of superior spatial resolution in comparison to micro-CT. Furthermore, this article presents the application of nano-CT for imaging cerebral microcirculation (murine), lung structures (porcine), and trabecular microstructure (ovine) in contrast to micro-CT imaging. This review shows the potential of nano-CT as a radiological method in biomedical basic research and discusses the application of experimental, high resolution CT techniques in consideration of other high resolution cross-sectional imaging techniques. Nano-computed tomography is a high resolution CT-technology for 3D imaging at sub-micrometer resolution. The technical concept bases on a further development of the established ex-vivo-micro-CT technology. By improvement of the spatial resolution, structures at a cellular level become visible (e.g. osteocyte lacunae). © Georg Thieme Verlag KG Stuttgart · New York.

  6. Evaluation of one year brain Computed Tomography scans at the ...

    African Journals Online (AJOL)

    Background: Advancement in technology has contributed immensely to medical practice. Computed tomography (CT), a yield of advanced technology has revolutionized the practice of neuroscience. Aim: To evaluate the first one year of brain computed tomography scan in the permanent site of University of Port Harcourt ...

  7. Diagnosis of lumbar disc hernia with computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Yoshizumi, Atsuro; Ohira, Nobuhiro; Ojima, Tadashi; Oshida, Midori; Horaguchi, Mitsuru (Tohoku Rosai Hospital, Sendai (Japan))

    1982-07-01

    Results of computed tomography performed on patients with clinically diagnosed hernia were compared with those of myelography and operative findings. This comparative study suggested that computed tomography is quite different from other methods and very useful in diagnosis of hernia. Some cases of hernia were shown, and the characteristics of CT were reviewed.

  8. Diagnosis of lumbar disc hernia with computed tomography

    International Nuclear Information System (INIS)

    Yoshizumi, Atsuro; Ohira, Nobuhiro; Ojima, Tadashi; Oshida, Midori; Horaguchi, Mitsuru

    1982-01-01

    Results of computed tomography performed on patients with clinically diagnosed hernia were compared with those of myelography and operative findings. This comparative study suggested that computed tomography is quite different from other methods and very useful in diagnosis of hernia. Some cases of hernia were shown, and the characteristics of CT were reviewed. (Ueda, J.)

  9. Cone beam computed tomography in Endodontics - a review

    NARCIS (Netherlands)

    Patel, S.; Durack, C.; Abella, F.; Shemesh, H.; Roig, M.; Lemberg, K.

    2015-01-01

    Cone beam computed tomography (CBCT) produces undistorted three-dimensional information of the maxillofacial skeleton, including the teeth and their surrounding tissues with a lower effective radiation dose than computed tomography. The aim of this paper is to: (i) review the current literature on

  10. Patient Dose From Megavoltage Computed Tomography Imaging

    International Nuclear Information System (INIS)

    Shah, Amish P.; Langen, Katja M.; Ruchala, Kenneth J.; Cox, Andrea; Kupelian, Patrick A.; Meeks, Sanford L.

    2008-01-01

    Purpose: Megavoltage computed tomography (MVCT) can be used daily for imaging with a helical tomotherapy unit for patient alignment before treatment delivery. The purpose of this investigation was to show that the MVCT dose can be computed in phantoms, and further, that the dose can be reported for actual patients from MVCT on a helical tomotherapy unit. Methods and Materials: An MVCT beam model was commissioned and verified through a series of absorbed dose measurements in phantoms. This model was then used to retrospectively calculate the imaging doses to the patients. The MVCT dose was computed for five clinical cases: prostate, breast, head/neck, lung, and craniospinal axis. Results: Validation measurements in phantoms verified that the computed dose can be reported to within 5% of the measured dose delivered at the helical tomotherapy unit. The imaging dose scaled inversely with changes to the CT pitch. Relative to a normal pitch of 2.0, the organ dose can be scaled by 0.67 and 2.0 for scans done with a pitch of 3.0 and 1.0, respectively. Typical doses were in the range of 1.0-2.0 cGy, if imaged with a normal pitch. The maximal organ dose calculated was 3.6 cGy in the neck region of the craniospinal patient, if imaged with a pitch of 1.0. Conclusion: Calculation of the MVCT dose has shown that the typical imaging dose is approximately 1.5 cGy per image. The uniform MVCT dose delivered using helical tomotherapy is greatest when the anatomic thickness is the smallest and the pitch is set to the lowest value

  11. Terahertz Computed Tomography of NASA Thermal Protection System Materials

    Science.gov (United States)

    Roth, D. J.; Reyes-Rodriguez, S.; Zimdars, D. A.; Rauser, R. W.; Ussery, W. W.

    2011-01-01

    A terahertz axial computed tomography system has been developed that uses time domain measurements in order to form cross-sectional image slices and three-dimensional volume renderings of terahertz-transparent materials. The system can inspect samples as large as 0.0283 cubic meters (1 cubic foot) with no safety concerns as for x-ray computed tomography. In this study, the system is evaluated for its ability to detect and characterize flat bottom holes, drilled holes, and embedded voids in foam materials utilized as thermal protection on the external fuel tanks for the Space Shuttle. X-ray micro-computed tomography was also performed on the samples to compare against the terahertz computed tomography results and better define embedded voids. Limits of detectability based on depth and size for the samples used in this study are loosely defined. Image sharpness and morphology characterization ability for terahertz computed tomography are qualitatively described.

  12. Emission computer tomography of the left ventricle

    Energy Technology Data Exchange (ETDEWEB)

    Semmler, W.; Felix, R.; Calder, D.; Golde, G.; Botsch, H.

    1983-10-01

    Tomographic studies and time-dependent tomograms on phantoms and patients were carried out using a 7-pinhole collimator in order to study the clinical value of ECG-triggered tomographic radionuclid ventriculography. A suitable computer programme has been developed. The results have shown that it is possible to evaluate local contraction abnormalities by this method. Using a left oblique position of the collimator (LAO (45/sup 0/) - cranial (15/sup 0/)), emission computer tomography is aligned with the longitudinal axis for the heart. In this way, a single projection is sufficient to show the montility of the anterior and posterior walls and of the septum. Hypokinesis, akinesis or dyskinesis can be recognised visually. The localisation and extent of the defect can be determined through the 7-pinhole collimator. Reconstructed images of the triggered radionuclide scintigrams show excellent marginal definition. In the RAO projection the left ventricle can be seen without superimposition and images obtained which equal those of a first-pass technique.

  13. Role of single photon emission computed tomography/computed tomography in diagnostic iodine-131 scintigraphy before initial radioiodine ablation in differentiated thyroid cancer

    International Nuclear Information System (INIS)

    Agrawal, Kanhaiyalal; Bhattacharya, Anish; Mittal, Bhagwant Rai

    2005-01-01

    The study was performed to evaluate the incremental value of single photon emission computed tomography/computed tomography (SPECT/CT) over planar radioiodine imaging before radioiodine ablation in the staging, management and stratification of risk of recurrence (ROR) in differentiated thyroid cancer (DTC) patients. Totally, 83 patients (21 male, 62 female) aged 17–75 (mean 39.9) years with DTC were included consecutively in this prospective study. They underwent postthyroidectomy planar and SPECT/CT scans after oral administration of 37–114 MBq iodine-131 (I-131). The scans were interpreted as positive, negative or suspicious for tracer uptake in the thyroid bed, cervical lymph nodes and sites outside the neck. In each case, the findings on planar images were recorded first, without knowledge of SPECT/CT findings. Operative and pathological findings were used for postsurgical tumor–node–metastasis staging. The tumor staging was reassessed after each of these two scans. Single photon emission computed tomography/computed tomography localized radioiodine uptake in the thyroid bed in 9/83 (10.8%) patients, neck nodes in 24/83 (28.9%) patients and distant metastases in 8/83 (9.6%) patients in addition to the planar study. Staging was changed in 8/83 (9.6%), ROR in 11/83 (13.2%) and management in 26/83 (31.3%) patients by the pretherapy SPECT/CT in comparison to planar imaging. SPECT/CT had incremental value in 32/83 patients (38.5%) over the planar scan. Single photon emission computed tomography/computed tomography is feasible during a diagnostic I-131 scan with a low amount of radiotracer. It improved the interpretation of pretherapy I-131 scintigraphy and changed the staging and subsequent patient management

  14. Giant hepatic cavernous hemangioma. Findings on computed helical tomography

    International Nuclear Information System (INIS)

    Castrillon, German A; Montoya, Maria del Pilar; Soto, Jorge A

    2010-01-01

    Objective: To describe computed helical tomography characteristics of the giant hepatic cavernous hemangioma. Method: During five years, we evaluated 21 patients with 21 giant hepatic cavernous hemangiomas with computed helical and multislice tomography. We included 18 women (86%) and 3 men (14%) with a mean age of 45 years. Results: The mean size of hemangiomas was 10.4 cm. Non enhanced computed tomography Showed 21 hemangiomas with lower density than adjacent hepatic parenchyma , all hemangiomas showed a central cleft area with low density. None hemangioma showed calcifications neither internal septa. In enhanced helical tomography all lesions demonstrated a globular, peripheral enhancing pattern with centripetal filling that begin in the arterial phase and continued in portal and delayed phases. None of the lesions showed complete filling. Conclusion: giant hepatic cavernous hemangiomas showed low attenuation in non enhanced computed tomography. central cleft area was very frequently seen. The enhancement pattern is characteristic, starting at the periphery with centripetal filling but it was never complete.

  15. The added value of 18F-fluorodeoxyglucose positron emission tomography computed tomography in patients with neck lymph node metastases from an unknown primary malignancy.

    Science.gov (United States)

    Prowse, S J B; Shaw, R; Ganeshan, D; Prowse, P M; Hanlon, R; Lewis-Jones, H; Wieshmann, H

    2013-08-01

    The search for a primary malignancy in patients with a metastatic cervical lymph node is challenging yet ultimately of utmost clinical importance. This study evaluated the efficacy of positron emission tomography computed tomography in detecting the occult primary, within the context of a tertiary referral centre head and neck cancer multidisciplinary team tumour board meeting. Thirty-two patients (23 men and 9 women; mean and median age, 61 years) with a metastatic cervical lymph node of unknown primary origin, after clinical examination and magnetic resonance imaging, underwent positron emission tomography computed tomography. The primary tumour detection rate was 50 per cent (16/32). Positron emission tomography computed tomography had a sensitivity of 94 per cent (16/17) and a specificity of 67 per cent (10/15). Combining these results with those of 10 earlier studies of similar patients gave an overall detection rate of 37 per cent. Positron emission tomography computed tomography has become an important imaging modality. To date, it has the highest primary tumour detection rate, for head and neck cancer patients presenting with cervical lymph node metastases from an unknown primary.

  16. Computed tomography in the diagnosis of equivocal appendicitis

    International Nuclear Information System (INIS)

    Cho, C.S.; Buckingham, J.M.; Mark Pierce; Hardman, D.T.

    1999-01-01

    The clinically obscure right iliac fossa (RIF) pain remains a diagnostic problem. The present study examines the use of computed tomography (CT) in improving the accuracy of clinical assessment in these difficult surgical cases. A retrospective review of all patients admitted under one surgeon with suspected acute appendicitis, between 1 January 1995 and 30 June 1997 was undertaken. The study setting was a district hospital (Calvary Hospital) that received patients from both an urban and rural environment. The patient cohort was identified from the Unit Registry and an International Classification of Diseases-based review of medical records. Twenty-one prospective data points were obtained from patient records. Those patients admitted with RIF pain and equivocal symptoms and signs subsequently underwent a CT and/or ultrasound (US) examination, conducted by the attending radiologist. For those patients who proceeded to appendicectomy, the histopathological findings were correlated with the imaging report. Those patients who were discharged after imaging without proceeding to operation were not readmitted to any regional hospital during the course of the study. Results: A total of 84 patients were identified. Thirty-three patients (39%) underwent appendicectomy without imaging and were excluded from further analysis. A total of 51 patients (61%) underwent 61 imaging procedures. The CT scan was correct in 35/36 patients (97%), while US was correct in 17/25 patients (68%). The present study suggests that CT can be used to improve the accuracy of diagnosis of obscure RIF pain. As a pilot study, it supports the development of a randomized controlled trial in a multicentre regional study

  17. Analysis of the computed tomography in the acute abdomen

    International Nuclear Information System (INIS)

    Hochhegger, Bruno; Moraes, Everton; Haygert, Carlos Jesus Pereira; Antunes, Paulo Sergio Pase; Gazzoni, Fernando; Lopes, Luis Felipe Dias

    2007-01-01

    Introduction: This study tends to test the capacity of the computed tomography in assist in the diagnosis and the approach of the acute abdomen. Material and method: This is a longitudinal and prospective study, in which were analyzed the patients with the diagnosis of acute abdomen. There were obtained 105 cases of acute abdomen and after the application of the exclusions criteria were included 28 patients in the study. Results: Computed tomography changed the diagnostic hypothesis of the physicians in 50% of the cases (p 0.05), where 78.57% of the patients had surgical indication before computed tomography and 67.86% after computed tomography (p = 0.0546). The index of accurate diagnosis of computed tomography, when compared to the anatomopathologic examination and the final diagnosis, was observed in 82.14% of the cases (p = 0.013). When the analysis was done dividing the patients in surgical and nonsurgical group, were obtained an accuracy of 89.28% (p 0.0001). The difference of 7.2 days of hospitalization (p = 0.003) was obtained compared with the mean of the acute abdomen without use the computed tomography. Conclusion: The computed tomography is correlative with the anatomopathology and has great accuracy in the surgical indication, associated with the capacity of increase the confident index of the physicians, reduces the hospitalization time, reduces the number of surgeries and is cost-effective. (author)

  18. Reproducibility in the assessment of acute pancreatitis with computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Freire Filho, Edison de Oliveira; Vieira, Renata La Rocca; Yamada, Andre Fukunishi; Shigueoka, David Carlos; Bekhor, Daniel; Freire, Maxime Figueiredo de Oliveira; Ajzen, Sergio; D' Ippolito, Giuseppe [Universidade Federal de Sao Paulo (UNIFESP/EPM), SP (Brazil). Dept. of Imaging Diagnosis]. E-mail: eofilho@ig.com.br; eoffilho@uol.com.br

    2007-11-15

    Objective: To evaluate the reproducibility of unenhanced and contrast-enhanced computed tomography in the assessment of patients with acute pancreatitis. Materials and methods: Fifty-one unenhanced and contrast-enhanced abdominal computed tomography studies of patients with acute pancreatitis were blindly reviewed by two radiologists (observers 1 and 2). The morphological index was separately calculated for unenhanced and contrast-enhanced computed tomography and the disease severity index was established. Intraobserver and interobserver reproducibility of computed tomography was measured by means of the kappa index ({kappa}). Results: Interobserver agreement was {kappa} 0.666, 0.705, 0.648, 0.547 and 0.631, respectively for unenhanced and contrast-enhanced morphological index, presence of pancreatic necrosis, pancreatic necrosis extension, and disease severity index. Intraobserver agreement (observers 1 and 2, respectively) was {kappa} = 0.796 and 0.732 for unenhanced morphological index; {kappa} 0.725 and 0.802 for contrast- enhanced morphological index; {kappa} = 0.674 and 0.849 for presence of pancreatic necrosis; {kappa} = 0.606 and 0.770 for pancreatic necrosis extension; and {kappa} = 0.801 and 0.687 for disease severity index at computed tomography. Conclusion: Computed tomography for determination of morphological index and disease severity index in the staging of acute pancreatitis is a quite reproducible method. The absence of contrast- enhancement does not affect the computed tomography morphological index reproducibility. (author)

  19. Medullary sponge kidney on axial computed tomography

    International Nuclear Information System (INIS)

    Ginalski, J.-M.; Schnyder, Pierre; Portmann, Luc; Jaeger, Philippe

    1991-01-01

    To evaluate features of medullary sponge kidney (MSK) on computed tomography (CT), 4-mm-thick axial slices without intravenous contrast material were 1st made in 13 patients through 24 kidneys which showed images of MSK on excretory urograms. On CT, papillary calcifications were found in 11 kidneys. In 5 of these, the calcifications were not detectable on plain films. Some hyperdense papillae (attenuation value 55-70 Hounsfield units) without calcification were found in 4 other kidneys. 9 kidneys appeared normal. 10 of the 14 kidneys were reexamined by a 2nd series of 4-mm-thick axial slices, 5 min after intravenous injection of 50 ml of Urografin. Images suggesting possible ectasia of precaliceal tubules were found in only 4 kidneys. These images appear much less obvious and characteristic on CT than on excretory urogram and do nothing more than suggest the possibility of MSK. In conclusion, the sensitivity of CT in the detection of MSK is markedly lower than that of excretory urography. In the most florid cases of the disease, CT can only show images suggesting the possibility of MSK. On the other hand, CT appears much more sensitive than plain films and tomograms of excretory in the detection of papillary calcifications, the most frequent complication of MSK. (author). 13 refs.; 3 figs

  20. Development of quantitative computed tomography lung protocols.

    Science.gov (United States)

    Newell, John D; Sieren, Jered; Hoffman, Eric A

    2013-09-01

    The purpose of this review article is to review the process of developing optimal computed tomography (CT) protocols for quantitative lung CT (QCT). In this review, we discuss the following important topics: QCT-derived metrics of lung disease; QCT scanning protocols; quality control; and QCT image processing software. We will briefly discuss several QCT-derived metrics of lung disease that have been developed for the assessment of emphysema, small airway disease, and large airway disease. The CT scanning protocol is one of the most important elements in a successful QCT. We will provide a detailed description of the current move toward optimizing the QCT protocol for the assessment of chronic obstructive pulmonary disorder and asthma. Quality control of CT images is also a very important part of the QCT process. We will discuss why it is necessary to use CT scanner test objects (phantoms) to provide frequent periodic checks on the CT scanner calibration to ensure precise and accurate CT numbers. We will discuss the use of QCT image processing software to segment the lung and extract the desired QCT metrics of lung disease. We will discuss the practical issues of using this software. The data obtained from the image processing software are then combined with those from other clinical examinations, health status questionnaires, pulmonary physiology, and genomics to increase our understanding of obstructive lung disease and improve our ability to design new therapies for these diseases.

  1. X-ray tubes for computed tomography

    International Nuclear Information System (INIS)

    Kotabe, Munenori; Sado, Noriyuki; Tachiki, Shigeru; Kitsuya, Minoru

    1979-01-01

    The X-ray tomography by computer processing (CT) is rapidly spreading because of the capabilities to obtain useful diagnostic information quantitatively, which was not able to be obtained by conventional X-ray photography, and to perform no-intrusion inspection, because it can picture the difference of X-ray absorption coefficient of several per cent in the soft tissues inside craniums. As the X-ray tubes to meet these requirements, the fixed anode X-ray tubes having high continuous rating are required for head CT, while the rotary anode X-ray tubes having the large cumulative heat capacity of anodes for whole body CT. Hitachi Ltd. has developed the X-ray tubes of type H 7129 of 4 kW rating for head CT and of type UJ-6FC-05V of 300 kHU (heat unit) for whole body CT. The specifications required for respective X-ray tubes include several items, and the maximum working tube voltage, focusing dimensions, long or short term maximum input and others are reported for the above described tubes. The performance centering around the loading life-time is described. In the tubes for whole body CT, repeated loading is also investigated. For the assumed input of 70,000 HU/slice, repeated loading of 10 times or more is possible in both cases when the input is repeatedly applied at loading intervals of 90 and 120 sec. (Wakatsuki, Y.)

  2. Cone beam computed tomography in veterinary dentistry.

    Science.gov (United States)

    Van Thielen, Bert; Siguenza, Francis; Hassan, Bassam

    2012-01-01

    The purpose of this study was to assess the feasibility of cone beam computed tomography (CBCT) in imaging dogs and cats for diagnostic dental veterinary applications. CBCT scans of heads of six dogs and two cats were made. Dental panoramic and multi-planar reformatted (MPR) para-sagittal reconstructions were created using specialized software. Image quality and visibility of anatomical landmarks were subjectively assessed by two observers. Good image quality was obtained for the MPR para-sagittal reconstructions through multiple teeth. The image quality of the panoramic reconstructions of dogs was moderate while the panoramic reconstructions of cats were poor since the images were associated with an increased noise level. Segmental panoramic reconstructions of the mouth seem to be useful for studying the dental anatomy especially in dogs. The results of this study using human dental CBCT technology demonstrate the potential of this scanning technology in veterinary medicine. Unfortunately, the moderate image quality obtained with the CBCT technique reported here seems to be inferior to the diagnostic image quality obtained from 2-dimensional dental radiographs. Further research is required to optimize scanning and reconstruction protocols for veterinary applications.

  3. Computed tomography of the mediastinal tumor

    International Nuclear Information System (INIS)

    Tohyama, Junko; Kono, Michio; Tauchi, Taneyasu; Mizutani, Masako; Mizutani, Hirokazu

    1984-01-01

    Forty-one cases of mediastinal tumor examined by computed tomography were reviewed. CT findings of the mediastinal malignancy were as follows: 1) inhomogeneous density on contrast CT, 2) equivocaton of fat plane surrounding the tumor, 3) irregular margin. Benign teratoma had smooth margin and included fat or calcification density. Mediastinal seminoma was observed as a lobulated mass with no calcification on CT. These findings were similar to the patterns of malignant thymoma or lymphoma. Consequently, it was very difficult to differentiate between malignant thymoma and malignant lymphoma by CT. According to our data, malignant thymoma tended to expand to only one side of the anterior mediastinum and to invade the anterior chest wall. On the other hand, malignant lymphoma of anterior medistinal type expanded into the trachea and the superior vena cava. In patients with sarcoidosis, the enlargement of bilateral hilar lymph nodes was commonly observed, on the contrary, unilateral hilar lymph nodes enlargement was recognized in some cases of malignant lymphoma. (author)

  4. Portable Digital Radiography and Computed Tomography Manual

    Energy Technology Data Exchange (ETDEWEB)

    2007-11-01

    This user manual describes the function and use of the portable digital radiography and computed tomography (DRCT) scanner. The manual gives a general overview of x-ray imaging systems along with a description of the DRCT system. An inventory of the all the system components, organized by shipping container, is also included. In addition, detailed, step-by-step procedures are provided for all of the exercises necessary for a novice user to successfully collect digital radiographs and tomographic images of an object, including instructions on system assembly and detector calibration and system alignment. There is also a short section covering the limited system care and maintenance needs. Descriptions of the included software packages, the DRCT Digital Imager used for system operation, and the DRCT Image Processing Interface used for image viewing and tomographic data reconstruction are given in the appendixes. The appendixes also include a cheat sheet for more experienced users, a listing of known system problems and how to mitigate them, and an inventory check-off sheet suitable for copying and including with the machine for shipment purposes.

  5. Computed Tomography Following Body Stuffing Heroin

    Directory of Open Access Journals (Sweden)

    Sean P. Nordt

    2015-12-01

    Full Text Available A 37-year-old male presented to the emergency department (ED in police custody for “medical clearance” before being taken to jail. The patient was approached by police officers for suspicion of selling illicit drugs. When approached by police he ran away and was witnessed to swallow several small plastic baggies suspected to contain heroin. He was apprehended and brought to the ED. On arrival, he was asymptomatic with a blood pressure 144/83mmHg, heart rate 67bpm, respiratory rate of 19bpm, oxygen saturation of 99% on room air and afebrile. A Glasgow coma score was 15 and he was alert and oriented to person, place and time. Patient had a negative review of systems. On physical examination pupils were 4mm and reactive to light, lungs clear to auscultation and had normal respiratory rate with normal cardiovascular exam. Abdomen was soft, non-tender and non-distended with present bowel sounds. The patient admitted to ingesting approximately 20 packets of heroin to avoid being charged with possession. The patient declined activated charcoal and whole bowel irrigation (WBI with polyethylene glycol-electrolyte solution (PEG-ELS. The patient declined a urine toxicology immunoassay screen. A computed tomography (CT of his abdomen with contrast was obtained and read as normal except for a cluster of foreign bodies within the distal stomach likely contained within a plastic bag.

  6. Computed tomography dose assessment - a practical approach

    International Nuclear Information System (INIS)

    Leitz, W.; Szendro, G.; Axelsson, B.

    1995-01-01

    A survey of the pattern and frequency of computed tomography (CT) examinations in Sweden has been conducted covering 89 of the 90 existing CT scanners (in 1991). The radiation output and the absorbed doses in phantoms have been measured for all types of CT scanners. For the assessment of the effective dose to the patient a new, practical approach has been developed. The average absorbed doses measured in cylindrical PMMA phantoms were assumed to be valid also for patients, those in the 320 mm diameter phantom for the trunk region and those in the 160 mm diameter phantom for the neck and head. With guidance from the ICRP 60 concept of tissue weighting factors, average weighting factors were adopted for the trunk, the neck, and the head region. Effective patient doses were calculated using three factors for doses measured in phantoms with the settings of exposure parameters as recorded in the survey. The results were compared with dose evaluations based on Monte Carlo calculations. The agreement was found to be satisfactory. It is suggested that this new practical approach should be adopted as a standard method for the assessment of effective dose in CT practices thus enabling direct access to dose evaluations in daily clinical practice -a prerequisite for the implementation of radiation protection concepts into the radiological society. (Author)

  7. Computed tomography findings in pancreas divisum

    International Nuclear Information System (INIS)

    Lindstroem, E.; Ihse, I.

    1989-01-01

    In 29 patients with abdominal pain the diagnosis of pancreas divisum (PD) was verified by endoscopic retrograde pancreatography (EPR) via both the major and the minor papilla. Computed tomography (CT) was done in all patients to evaluate contour, volume, antero-posterior diameters and attenuation values of the gland in comparison with a normal reference series. Also, the validity of the CT grading of pancreatitis was assessed in comparison with ERP grading. Patients with PD had an increased cranio-caudal diameter of the pancreatic head (p<0.001). Further, the main pancreatic duct was visualized more often in patients with PD (p<0.01), who also had an increasing frequency of pancreatic calcifications (p<0.05). Otherwise there were no differences compared with the normal series. The observed reduction in the volume of the gland in patients with marked pancreatitis at ERP seemingly reflected the severity of inflammation. No cleavage between the dorsal and ventral anlage was identified. CT was found to be too unspecific to be of any use in grading of pancreatitis. In conclusion, CT findings in patients with PD are sparse, unspecific and preferably a reflection of pancreatitis, if present. ERP remains the ''gold standard'' for the diagnosis. (orig.)

  8. X-ray diffraction computed tomography

    International Nuclear Information System (INIS)

    Harding, G.; Kosanetzky, J.; Neitzel, U.

    1987-01-01

    Coherent scattering of x-ray photons leads to the phenomenon of x-ray diffraction, which is widely used for determining atomic structure in materials science. A technique [x-ray diffraction computed tomography (CT)] is described, analogous to conventional CT, in which the x-ray diffraction properties of a stack of two-dimensional object sections may be imaged. The technique has been investigated using a first generation (single pencil beam) CT scanner to measure small angle coherent scatter, in addition to the customary transmitted radiation. Diffraction data from a standard CT performance phantom obtained with this new technique and with an x-ray diffractometer are compared. The agreement is satisfactory bearing in mind the poor momentum resolution of our apparatus. The dose and sensitivity of x-ray diffraction CT are compared with those of conventional transmission CT. Diffraction patterns of some biological tissues and plastics presented in a companion paper indicate the potential of x-ray diffraction CT for tissue discrimination and material characterization. Finally, possibilities for refinement of the technique by improving the momentum resolution are discussed

  9. Gradient computation for VTI acoustic wavefield tomography

    KAUST Repository

    Li, Vladimir

    2016-09-06

    Wavefield tomography can handle complex subsurface geology better than ray-based techniques and, ultimately, provide a higher resolution. Here, we implement forward and adjoint wavefield extrapolation for VTI (transversely isotropic with a vertical symmetry axis) media using a pseudospectral operator that employes a separable approximation of the P-wave dispersion relation. This operator is employed to derive the gradients of the differential semblance optimization (DSO) and modified stack-power objective functions. We also obtain the gradient expressions for the data-domain objective function, which can incorporate borehole information necessary for stable VTI velocity analysis. These gradients are compared to the ones obtained with a space-time finite-difference (FD) scheme for a system of coupled wave equations. Whereas the kernels computed with the two wave-equation operators are similar, the pseudospectral method is not hampered by the imprint of the shear-wave artifact. Numerical examples also show that the modified stack-power objective function produces cleaner gradients than the more conventional DSO operator.

  10. Computed tomography in acute ischemic stroke

    International Nuclear Information System (INIS)

    Loevblad, Karl-Olof; Baird, Alison E.

    2010-01-01

    Stroke remains the third most important cause of mortality in industrialized countries; this has prompted research for improvements in both diagnostic and therapeutic strategies for patients with signs of acute cerebral ischemia. Over the last decade, there has been a parallel in progress in techniques in both diagnostic and therapeutic options. While previously only used for excluding hemorrhage, imaging now has the possibility to detect ischemia, vascular occlusion, as well as detect tissue at risk in one setting. It should also allow to monitor treatment and predict/exclude therapeutic complications. Parallel to advances in magnetic resonance imaging of stroke, computed tomography has improved immensely over the last decade due to the development of CT scanners that are faster and that allow to acquire studies such as CT perfusion or CT angiography in a reliable way. CT can detect many signs that might help us detect impending signs of massive infarction, but we still lack the experience to use these alone to prevent a patient from benefitting from possible therapy. (orig.)

  11. Diagnosis of choledocholithiasis by computed tomography

    International Nuclear Information System (INIS)

    Lee, Jae Sub; Kang, Kyung Sook; Lee, Yul; Chung, Soo Young; Bae, Sang Hoon; Yoon, Jong Sup

    1986-01-01

    In order to determine the value of Computed Tomography (CT) in the diagnosis of choledocholithiasis, the authors retrospectively studied 33 cases of choledocholithiasis proven by surgery from January 1983 to June 1985. Among them, 15 cases were examined by both CT and ultrasonography. The results were as follows: 1. There were 12 men and 21 women with mean age of 57 years. 2. CT correctly diagnosed choledocholithiasis in 29(88%) of total 33 cases. There were 4 false negative diagnoses and there were no false positive. 3. In 15 cases which were examined by both CT and ultrasonography, 13(86%) cases were correctly diagnosed by CT and 7(46%) by ultrasonography. 4. The majority (88%) of choledocholithiasis were demonstrated as calcific density and 4 cases (12%) were nearly isotense to pancreas. 5. Most cases were shown as homogenous density and 5 cases (16%) as ringlike structure with low density center and high density periphery. 6. Additional findings, such as intrahepatic and/or GB stones, paricholangitic abscess, GB empyema, ascites, and liver cirrhosis were also identified by CT. 7. CT is effective for noninvasive and accurate detection of choledocholithiasis. So invasive cholangiography, such as E.R.C.P or P.T.C can be reserved in many cases of choledocholithiasis.

  12. Diagnosis of choledocholithiasis by computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jae Sub; Kang, Kyung Sook; Lee, Yul; Chung, Soo Young; Bae, Sang Hoon; Yoon, Jong Sup [Hallym University College of Medicine, Seoul (Korea, Republic of)

    1986-02-15

    In order to determine the value of Computed Tomography (CT) in the diagnosis of choledocholithiasis, the authors retrospectively studied 33 cases of choledocholithiasis proven by surgery from January 1983 to June 1985. Among them, 15 cases were examined by both CT and ultrasonography. The results were as follows: 1. There were 12 men and 21 women with mean age of 57 years. 2. CT correctly diagnosed choledocholithiasis in 29(88%) of total 33 cases. There were 4 false negative diagnoses and there were no false positive. 3. In 15 cases which were examined by both CT and ultrasonography, 13(86%) cases were correctly diagnosed by CT and 7(46%) by ultrasonography. 4. The majority (88%) of choledocholithiasis were demonstrated as calcific density and 4 cases (12%) were nearly isotense to pancreas. 5. Most cases were shown as homogenous density and 5 cases (16%) as ringlike structure with low density center and high density periphery. 6. Additional findings, such as intrahepatic and/or GB stones, paricholangitic abscess, GB empyema, ascites, and liver cirrhosis were also identified by CT. 7. CT is effective for noninvasive and accurate detection of choledocholithiasis. So invasive cholangiography, such as E.R.C.P or P.T.C can be reserved in many cases of choledocholithiasis.

  13. Renal imaging diagnosis by computed tomography

    International Nuclear Information System (INIS)

    Nishitani, Hiromu

    1984-01-01

    The sizes of the kidneys of 96 persons without known renal diseases were measured using computed tomography. The average renal length consisted of 10 transverse sections, each 10 mm thick, with a standard deviation of 1 such section. The mean renal width was 61 +- 6.8 mm on the left, and 64 +- 6.4 mm on the right. The mean renal thickness was 51 +- 6.1 mm on the left, and 49 +- 6.9 mm on the right. The renal parenchyma averaged 14 +- 2.2 mm in thickness, regardless of side or sex. Measurement errors were estimated to be approximately 10 percent. There were no significant differences in renal length according to CT and angiography. Renal measurements determined by CT are useful in predicting vital kidney sizes. The CT findings among 114 patients with various renal diseases were compared with results of their excretory urographic and/or angiographic studies. In nearly all instances, CT was superior to excretory urography in detecting renal diseases. It was unnecessary to confirm renal abnormalities detected by CT using excretory urography. CT compared favorably with angiography in the definitive diagnostic imaging and staging of renal cell carcinomas. CT is destined to play an important role in the diagnostic imaging of renal diseases. (author)

  14. Dynamic X-ray computed tomography

    International Nuclear Information System (INIS)

    Grangeat, P.

    2003-01-01

    Paper Dynamic computed tomography (CT) imaging aims at reconstructing image sequences where the dynamic nature of the living human body is of primary interest. Main concerned applications are image-guided interventional procedures, functional studies and cardiac imaging. The introduction of ultra-fast rotating gantries along with multi-row detectors and in near future area detectors allows a huge progress toward the imaging of moving organs with low-contrast resolution. This paper gives an overview of the different concepts used in dynamic CT. A new reconstruction algorithm based on a voxel-specific dynamic evolution compensation is also presented. It provides four-dimensional image sequences with accurate spatio-temporal information, where each frame is reconstructed using a long-scan acquisition mode on several half-turns. In the same time, this technique permits to reduce the dose delivered per rotation while keeping the same signal to noise ratio for every frame using an adaptive motion-compensated temporal averaging. Results are illustrated on simulated data. (authors)

  15. Ruptured ectopic pregnancy diagnosed with computed tomography

    International Nuclear Information System (INIS)

    Michalak, Maciej; Żurada, Anna; Biernacki, Maciej; Zygmunt, Kozielec

    2010-01-01

    The rupture of ectopic pregnancy (EP) still remains the primary and direct cause of death in the first trimester of pregnancy. Ultrasonography is known to be a modality of choice in EP diagnostics. We found a severe discrepancy between the frequency of ectopic pregnancies (EP) and the number of available computed tomography (CT) examinations. A 29-year-old woman was admitted to the emergency department with a history of abdominal pain, nausea, vomiting and collapse. Sonographic findings of a suspected EP were unclear. Moreover, not all features of intrauterine pregnancy were present. Due to the patient’s life-threatening condition, an emergency multi-slice CT with MPR and VRT reconstructions was performed, revealing symptoms of a ruptured EP. In the right adnexal area, a well-vascularized, solid-cystic abnormal mass lesion was found. Intraperitoneal hemorrhage was confirmed intraoperatively, and the right fallopian tube with a tubal EP was resected. In the surgery in situ, as well as in the pathological examination of the tumor mass, a human embryo of approximately 1.5 cm in length (beginning of the 8 th week of gestation) was found. Although ultrasonography still remains the first-line imaging examination in EP diagnostics, sometimes the findings of suspected EPs are unclear and not sufficient. The rupture of EP, with serious bleeding and symptoms of shock, may require an emergent pelvic and abdominal CT inspection. A clear correlation was found between the macroscopic CT images and the intraoperatively sampled material

  16. Computer tomography and urinary calculi, 2

    International Nuclear Information System (INIS)

    Kageyama, Shizuichi; Kuwahara, Masaaki; Kurosu, Seiichi; Orikasa, Seiichi

    1986-01-01

    To find whether computer tomography (CT) can determine the composition of urinary calculi, we measured the CT values of 47 calculi in vitro and 26 calculi in situ. The results are as follows; 1) CT values (Hounsfield Unit) of various stones which were measured in vitro (mean ± s.d.) were as follows; mixed calcium oxalate and calcium phosphate (the mixed stone) 1555 ± 193 H, magnecium ammonium phosphate (MAP) 1285 ± 248 H, cystine 757 ± 114 H, uric acid 480 H. 2) In situ the peak CT values of various calculi were almost the same as those in vitro, but the mean CT values were slightly less. 3) From these results we concluded that cystine and uric acid stones can be identified by the CT value. With regard to the mixed stone and MAP, it is almost impossible to identify these stones especially when they reveal the CT values of 1100 - 1500 H. However, stones with the peak CT values of more than 1500 H were rarely MAP and often the mixed stone, and those with the mean CT values of 1000 - 1100 H were rarely the mixed stone and often MAP. (author)

  17. Advanced proton imaging in computed tomography.

    Science.gov (United States)

    Mattiazzo, S; Bisello, D; Giubilato, P; Pantano, D; Pozzobon, N; Snoeys, W; Wyss, J

    2015-09-01

    In recent years the use of hadrons for cancer radiation treatment has grown in importance, and many facilities are currently operational or under construction worldwide. To fully exploit the therapeutic advantages offered by hadron therapy, precise body imaging for accurate beam delivery is decisive. Proton computed tomography (pCT) scanners, currently in their R&D phase, provide the ultimate 3D imaging for hadrons treatment guidance. A key component of a pCT scanner is the detector used to track the protons, which has great impact on the scanner performances and ultimately limits its maximum speed. In this article, a novel proton-tracking detector was presented that would have higher scanning speed, better spatial resolution and lower material budget with respect to present state-of-the-art detectors, leading to enhanced performances. This advancement in performances is achieved by employing the very latest development in monolithic active pixel detectors (to build high granularity, low material budget, large area silicon detectors) and a completely new proprietary architecture (to effectively compress the data). © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  18. Computed tomography of the alveolar bone

    International Nuclear Information System (INIS)

    Schueller, H.

    1996-01-01

    In addition to the conventional radiological methods used in odontology, computed tomography (CT) provides superposition-free images of the mandible and maxilla. Its value has been proved not only in cases of malignancy but also in many other problems. If an examination is performed with a slice thickness of less than 1.5 mm, the form and position of retained teeth in the alveolar bone, as well as subsequent lesions of neighboring permanent teeth, can be visualized so that early treatment can be planned. If the parodontal space of a retained tooth is visible, orthodontic intervention is possible. Precise assessment of horizontal or vertical bone loss is essential in inflammatory dental diseases. The morphology and extent of benign cystic lesions are also shown by CT. With CT surgical strategy of an intended implant therapy can take into account the remaining bone substance and the exact position of nerves and foramina. If such therapy is possible, the location, form and number of implants are easily defined. (orig.) [de

  19. Image quality in coronary computed tomography angiography

    DEFF Research Database (Denmark)

    Precht, Helle; Gerke, Oke; Thygesen, Jesper

    2018-01-01

    Background Computed tomography (CT) technology is rapidly evolving and software solution developed to optimize image quality and/or lower radiation dose. Purpose To investigate the influence of adaptive statistical iterative reconstruction (ASIR) at different radiation doses in coronary CT...... angiography (CCTA) in detailed image quality. Material and Methods A total of 160 CCTA were reconstructed as follows: 55 scans with filtered back projection (FBP) (650 mA), 51 scans (455 mA) with 30% ASIR (ASIR30), and 54 scans (295 mA) with 60% ASIR (ASIR60). For each reconstruction, subjective image quality...... was assessed by five independent certified cardiologists using a visual grading analysis (VGA) with five predefined image quality criteria consisting of a 5-point scale. Objective measures were contrast, noise, and contrast-to-noise ratio (CNR). Results The CTDIvol resulted in 10.3 mGy, 7.4 mGy, and 4.6 m...

  20. Computed tomography of lacrimal fossa tumors

    International Nuclear Information System (INIS)

    Park, Chan Sup; Kim, Young Goo; Chang, Kee Hyun

    1985-01-01

    The lacrimal fossa can be involved by a wide spectrum of orbital pathology. The correct diagnosis is important to avoid unnecessary procedure and to do appropriate management. 14 patients with mass lesions in the lacrimal fossa were evaluated with computed tomography (CT) and clinical findings. The results were as follows: 1. Final diagnosis of 14 cases with lacrimal fossa tumors was pleomorphic adenoma in 3 cases, adenoid cystic carcinoma in 1 case, pseudotumor in 5 cases, lymphoma in 2 cases, neurofibroma in 1 case, chloroma in 1 case and metastatic adenocarcinoma in 1 case. 2. The duration of symptoms of pleomorphic adenoma was more than 1 year and characteristic CT findings were globular masses with pressure erosion of the adjacent bone. Patient with adenoid cystic carcinoma had a short history of symptoms. CT showed a fusiform mass but intracranial extension with frank destruction of sphenoid bone. 3. Patients with pseudotumor and lymphoma had symptoms for less than 1 year. The CT findings were ill-defined infiltrative patterns with scleral thickening and the differential diagnosis of them was difficult. 4. The margins of neurofibroma and chloroma were well defined while that of the metastic adenocarcinoma was ill-defined. 5. The degree and the extent of the contrast enhancement gave no benefit in the differential diagnosis of each disease entities and even of the benign and malignant lesions

  1. Computed tomography of the breast cancer

    Energy Technology Data Exchange (ETDEWEB)

    Chung, Soo Young; Lee, Yul; Bae, Sang Hoon; Yoon, Jong Sup; Lee, Ki Chu [Hallym University Medical Center, Seoul (Korea, Republic of)

    1985-12-15

    The indication of computed tomography for the breast lesion are 1) Unusually extensive or small breast caused technical difficulties in performing mammograms. 2) Questionable mammographic findings, especially in dense proliferative breast parenchyme. 3) Microcancer. 4) Suspicious regional lymph node enlargement or invasive of the chest wall by breast cancer. The diagnosis of breast CT in breast cancer is based on pathologic anatomic changes and characteristic increase of mean CT No. of lesion following contrast enhancement. Authors analysed CT of the 34 patients who were clinically suspected breast cancer, and compared with mammography. The results are as follows: 1. Pathological diagnosis of 34 cases were 27 cases of breast cancer, 4 cases of fibrocystic disease, 2 cases of fibroadenoma, and 1 case of intraductal papilloma. The diagnostic accuracy of CT in 27 breast cancer was 93% (25 cases) and mammography 71% (19 case). 2. Correct diagnosis of CT in 7 benign breast disease is in 5 cases and mammography in 5 cases. 3. The most important finding of CT in breast cancer is characteristic increase of CT No. of lesion following contrast enhancement (200 ml, 65%): over average 50 HU in 19 cases of 27 breast cancers, 30-50 HU in a 6 cases, 20-30 HU in 2 cases with tumor necrosis. 4. Computed with mammography, other more valuable CT findings of breast cancer are axillary lymph node enlargement and adjacentic pectoral muscle invasion. 5. In conclusion, breast CT is considered as valuable diagnostic tool in evaluation of breast cancer, but not of benign breast disease.

  2. Computer stress study of bone with computed tomography

    International Nuclear Information System (INIS)

    Linden, M.J.; Marom, S.A.; Linden, C.N.

    1986-01-01

    A computer processing tool has been developed which, together with a finite element program, determines the stress-deformation pattern in a long bone, utilizing Computed Tomography (CT) data files for the geometry and radiographic density information. The geometry, together with mechanical properties and boundary conditions: loads and displacements, comprise the input of the Finite element (FE) computer program. The output of the program is the stresses and deformations in the bone. The processor is capable of developing an accurate three-dimensional finite element model from a scanned human long bone due to the CT high pixel resolution and the local mechanical properties determined from the radiographic densities of the scanned bone. The processor, together with the finite element program, serves first as an analysis tool towards improved understanding of bone function and remodelling. In this first stage, actual long bones may be scanned and analyzed under applied loads and displacements, determined from existing gait analyses. The stress-deformation patterns thus obtained may be used for studying the biomechanical behavior of particular long bones such as bones with implants and with osteoporosis. As a second stage, this processor may serve as a diagnostic tool for analyzing the biomechanical response of a specific patient's long long bone under applied loading by utilizing a CT data file of the specific bone as an input to the processor with the FE program

  3. Preoperative computed tomography of the brain in non-small cell bronchogenic carcinoma.

    Science.gov (United States)

    Kormas, P; Bradshaw, J R; Jeyasingham, K

    1992-01-01

    BACKGROUND: Computed tomography of the brain is the most accurate diagnostic investigation for detecting intracranial tumours. A prospective study was undertaken to try to maximise the cost effectiveness of computed tomography of the brain in the preoperative evaluation of non-small cell lung cancer. METHODS: All patients with non-small cell lung cancer who were free of neurological symptoms and were thought to be free of metastases from the results of routine investigations were subjected to computed tomography of the brain in the 12-24 hours immediately before surgery. RESULTS: Of 158 such patients, five showed positive evidence of metastases, confirmed on craniotomy and excision biopsy; one of these patients was found to have a non-metastatic tumour (false positive). Five patients with a negative scan who underwent lung resection returned within 12 months with neurological defects and positive findings on further computed tomography (false negative). The predominant cell type in patients with positive and false negative scans was adenocarcinoma or adenosquamous carcinoma (7/10); the majority had nodal state N2. CONCLUSIONS: Computed tomography of the brain should be carried out if mediastinal disease is suspected or confirmed in non-small cell lung cancer before proceeding to surgery. PMID:1549816

  4. Diagnosis of hoof disease in horses using computed tomography

    Directory of Open Access Journals (Sweden)

    Kovač Milomir

    2002-01-01

    Full Text Available This study describes findings of computed tomography investigations at the Bergische Equine Clinic (Germany of 39 horses with hoof diseaseas. The most frequently findings were the navicular syndrome (eight horses, laminitis (seven horses, keratnoma (six horses and ossification of collateral cartilages in the distal phalanx (four horses. The special value of the computed tomography is in evaluating the size and courses fracture/fissure of the navicular and koffin bones, which were diagnose in five horses. In four of horses no pathologic changes of the hoof were determined by computed tomography.

  5. Diagnosis of hoof diseases in horses using computed tomography

    International Nuclear Information System (INIS)

    Kovac, M.; Nowak, M.; Kaufels, N.; Tambur, Z.

    2002-01-01

    This study describes findings of computed tomography investigations at the Bergische Equine Clinic (Bergische Tierklinik), Germany, of 39 horses with hoof diseases. The most frequently findings were the navicular syndrome (eight horses), laminitis (seven horses), keratnoma (six horses) and ossification of collateral cartilages in the distal phalanx (four horses). The special value of the computed tomography is in evaluating the size and courses fracture/fissure of the navicular and koffin bones, which were diagnose in five horses. In four of horses no pathologic changes of the hoof were determined by computed tomography

  6. Diffuse abnormalities of the trachea: computed tomography findings

    Energy Technology Data Exchange (ETDEWEB)

    Marchiori, Edson [Universidade Federal Fluminense (UFF), Niteroi, RJ (Brazil). Dept. de Radiologia]. E-mail: edmarchiori@gmail.com; Pozes, Aline Serfaty [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil). Faculdade de Medicina. Dept. de Radiologia; Souza Junior, Arthur Soares [Faculdade de Medicina de Sao Jose do Rio Preto (FAMERP), SP (Brazil). Escola de Medicina. Dept. de Radiologia; Escuissato, Dante Luiz [Universidade Federal do Parana (UFPR), Curitiba, PR (Brazil). Dept. de Radiologia; Irion, Klaus Loureiro [The Cardiothoracic Centre NHS Trust, Liverpool (United Kingdom); Araujo Neto, Cesar de [Universidade Federal da Bahia (UFBA), Salvador, BA (Brazil). Dept. de Radiologia; Barillo, Jorge Luiz; Zanetti, Glaucia [Faculdade de Medicina de Petropolis (FMP), RJ (Brazil). Dept. de Cirurgia Clinica; Souza, Carolina Althoff [University of Ottawa, Ottawa, ON (Canada)

    2008-01-15

    The aim of this pictorial essay was to present the main computed tomography findings seen in diffuse diseases of the trachea. The diseases studied included amyloidosis, tracheobronchopathia osteochondroplastica, tracheobronchomegaly, laryngotracheobronchial papillomatosis, lymphoma, neurofibromatosis, relapsing polychondritis, Wegener's granulomatosis, tuberculosis, paracoccidioidomycosis, and tracheobronchomalacia. The most common computed tomography finding was thickening of the walls of the trachea, with or without nodules, parietal calcifications, or involvement of the posterior wall. Although computed tomography allows the detection and characterization of diseases of the central airways, and the correlation with clinical data reduces the diagnostic possibilities, bronchoscopy with biopsy remains the most useful procedure for the diagnosis of diffuse lesions of the trachea. (author)

  7. Computed tomography of the llama head: technique and normal anatomy

    International Nuclear Information System (INIS)

    Hathcock, J.T.; Pugh, D.G.; Cartee, R.E.; Hammond, L.

    1996-01-01

    Computed tomography was performed on the head of 6 normal adult llamas. The animals were under general anesthesia and positioned in dorsal recumbency on the scanning table. The area scanned was from the external occipital protuberance to the rostral portion of the nasal passage, and the images are presented in both a bone window and a soft tissue window to allow evaluation and identification of the anatomy of the head. Computed tomography of the llama head can be accomplished by most computed tomography scanners utilizing a technique similar to that used in small animals with minor modification of the scanning table

  8. 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)

  9. The Utility of Dual Energy Computed Tomography in Musculoskeletal Imaging

    Directory of Open Access Journals (Sweden)

    Sachin Khanduri

    2017-01-01

    Full Text Available The objective of this article is to review the mechanisms, advantages and disadvantages of dual energy computed tomography (DECT over conventional tomography (CT in musculoskeletal imaging as DECT provides additional information about tissue composition and artifact reduction. This provides clinical utility in detection of urate crystals, bone marrow edema, reduction of beam hardening metallic artifact, and ligament and tendon analysis.

  10. Significance of pulmonary nodules in multi-detector computed tomography scan of noncancerous patients

    OpenAIRE

    Toghiani, Ali; Adibi, Atoosa; Taghavi, Arash

    2015-01-01

    Background: Computed tomography (CT) scan is one the most useful devices in chest imaging. CT scan can be used in mediastinal abnormality, lungs, and pleural evaluations. According to the high prevalence and different causes of pulmonary nodules, we designed this study to evaluate the prevalence and the types of pulmonary nodules in noncancerous patients who underwent chest multi-detector CT (MDCT) scan. Materials and Methods: This was a cross-sectional study which was in our hospital to eval...

  11. Rapid Healing of a Spontaneous Coronary Artery Dissection Detected by Computed Tomography Angiography.

    Science.gov (United States)

    Sakai, Koyu; Kobayashi, Yohei; Shirai, Shinichi; Ando, Kenji

    2018-03-20

    Spontaneous coronary artery dissection (SCAD) is a rare cause of acute coronary syndrome and little is known about characteristics, treatment, and follow-up of patients with SCAD. Computed tomography angiography (CTA) plays an important role in the diagnosis and management of SCAD. Herein, we describe a case of a patient with SCAD who underwent successful conservative management, and in whom CTA was able to detect rapid healing of the dissection, 4.5 hours post-dissection.

  12. Positron emission tomography-computed tomography has a clinical impact for patients with cervical cancer

    DEFF Research Database (Denmark)

    Sandvik, Rikke Mulvad; Jensen, Pernille Tine; Hendel, Helle W

    2011-01-01

    Many studies have found that positron emission tomography-computed tomography (PET-CT) has a high sensitivity and specificity in the identification of metastasis in cervical cancer. Herlev Hospital, Denmark, has been performing PET-CTs in stage I-IV cervical cancer since 1 May 2006. The present...

  13. Positron emission tomography/computed tomography for optimized colon cancer staging and follow up

    DEFF Research Database (Denmark)

    Engelmann, Bodil Elisabeth; Loft, Annika; Kjær, Andreas

    2014-01-01

    OBJECTIVES: Optimal management of colon cancer (CC) requires detailed assessment of extent of disease. This study prospectively investigates the diagnostic accuracy of 2-deoxy-2-[18F]fluoro-D-glucose positron emission tomography/computed tomography (PET/CT) for staging and detection of recurrence...

  14. Fluorine-18 fluorodeoxyglucose positron emission tomography-computed tomography in evaluation of residual intramuscular myxoma

    International Nuclear Information System (INIS)

    Zade, Anand; Ahire, Archana; Shetty, Shishir; Rai, Sujith; Bokka, Rajashekharrao; Velumani, Arokiaswamy; Kabnurkar, Rasika

    2015-01-01

    Intramuscular myxoma (IM) is a rare benign neoplasm. In a patient diagnosed with IM of left thigh, we report the utility of a postoperative fluorine-18 fluorodeoxyglucose positron emission tomography-computed tomography scan in assessing the efficacy of surgical excision

  15. Computed Tomography diagnosis of skeletal involvement in multiple myeloma

    International Nuclear Information System (INIS)

    Scutellari, Pier Nuccio; Galeotti, Roberto; Leprotti, Stefano; Piva, Nadia; Spanedda, Romedio

    1997-01-01

    The authors assess the role of Computed Topography in the diagnosis and management of multiple myeloma (MM) and investigate if Computed Tomography findings can influence the clinical approach, prognosis and treatment. 273 multiple myeloma patients submitted to Computed Tomography June 1994, to December, 1996. The patients were 143 men and 130 women (mean age: 65 years): 143 were stage I, 38 stage II and 92 stage III according to Durie and Salomon's clinical classification. All patients were submitted to blood tests, spinal radiography and Computed Tomography, the latter with serial 5-mm scans on several vertebral bodies. Computed Tomography despicted vertebral arch and process involvement in 3 cases with the vertebral pedicle sign. Moreover, Computed Tomography proved superior to radiography in showing the spread of myelomatous masses into the soft tissues in a case with solitary permeative lesion in the left public bone, which facilitated subsequent biopsy. As for extraosseous localizations, Computed Tomography demonstrated thoracic soft tissue (1 woman) and pelvic (1 man) involvement by myelomtous masses penetrating into surrounding tissues. In our series, only a case of osteosclerotic bone myeloma was observed in the pelvis, associated with lytic abnormalities. Computed Tomography findings do not seem to improve the clinical approach and therapeutic management of the disease. Nevertheless, the authors reccommend Computed Tomography for some myelomatous conditions, namely: a) in the patients with focal bone pain but normal skeletal radiographs; b) in the patients with M protein, bone marrow plasmocytosis and back pain, but with an incoclusive multiple myeloma diagnosis; c) to asses bone spread in the regions which are anatomically complex or difficult to study with radiography and to depict soft tissue involvement; d) for bone biopsy

  16. Primary pulmonary lymphoma-role of fluoro-deoxy-glucose positron emission tomography-computed tomography in the initial staging and evaluating response to treatment - case reports and review of literature

    International Nuclear Information System (INIS)

    Agarwal, Krishan Kant; Dhanapathi, Halanaik; Nazar, Aftab Hasan; Kumar, Rakesh

    2016-01-01

    Primary pulmonary lymphoma (PPL) is an uncommon entity of non-Hodgkin lymphoma, which accounts for <1% of all cases of lymphoma. We present two rare cases of PPL of diffuse large B-cell lymphoma, which underwent 18 fluorine fluoro-deoxy-glucose positron emission tomography-computed tomography for initial staging and response evaluation after chemotherapy

  17. Computer aided stress analysis of long bones utilizing computer tomography

    International Nuclear Information System (INIS)

    Marom, S.A.

    1986-01-01

    A computer aided analysis method, utilizing computed tomography (CT) has been developed, which together with a finite element program determines the stress-displacement pattern in a long bone section. The CT data file provides the geometry, the density and the material properties for the generated finite element model. A three-dimensional finite element model of a tibial shaft is automatically generated from the CT file by a pre-processing procedure for a finite element program. The developed pre-processor includes an edge detection algorithm which determines the boundaries of the reconstructed cross-sectional images of the scanned bone. A mesh generation procedure than automatically generates a three-dimensional mesh of a user-selected refinement. The elastic properties needed for the stress analysis are individually determined for each model element using the radiographic density (CT number) of each pixel with the elemental borders. The elastic modulus is determined from the CT radiographic density by using an empirical relationship from the literature. The generated finite element model, together with applied loads, determined from existing gait analysis and initial displacements, comprise a formatted input for the SAP IV finite element program. The output of this program, stresses and displacements at the model elements and nodes, are sorted and displayed by a developed post-processor to provide maximum and minimum values at selected locations in the model

  18. Computed tomography in Duchenne type muscular dystrophy

    International Nuclear Information System (INIS)

    Kawai, Mitsuru; Kunimoto, Masanari; Motoyoshi, Yasufumi; Kuwata, Takashi; Nakano, Imaharu

    1985-01-01

    The computed tomography (CT) scan was performed on 91 Duchenne type muscular dystrophy (DMD) patients on the following four levels; (1) at the level of L3 vertebra, (2) 2-3cm above the symphysis pubica, (3) midposition of the thigh, (4) largest-diameter section of the lower leg. The CT of muscles common to most of the DMD patients were as follows: 1. Muscle atrophy: Muscle atrophy was shown as a reduction in the cross-sectional area of the muscles. Very mild muscle atrophy could be detected either by the clearly identified muscle border or by scattered low-density areas of so-called ''moth-eaten'' appearance within muscles. 2. Fat infiltration: The decrease in radio-density of muscles was interpreted as infiltration of fatty tissue. This type of density change was further classified into diffuse, streaked, cobblestone and salt-and-pepper patterns according to the spacial distribution of low-density areas. 3. Selectivity pattern: As the chronological sequence of DMD muscle degeneration is usually different among individual muscles, it may be seen, in some stages, that some of the synergistic muscles are still only slightly involved, while the others are quite severely atrophied with evident fat infiltration. In certain stages of the disease, most of the patients show relative preservation of particular muscles although they assumed a rounded shape. The most resistent muscle was musculus gracilis, followed by the musculus sartorius, musculus semitendinosus (and/or musculus semimembranosus) in that order. According to the severity of the CT changes, 86 of the 91 patients were classed into five stages from A1 to A5. Morphological stages (A1-A5) were well correlated to the functional disability stages by Ueda with a correlation factor of r=0.88. (J.P.N.)

  19. Radiological protection in paediatric computed tomography

    International Nuclear Information System (INIS)

    Khong, P-L.; Frush, D.; Ringertz, H.

    2012-01-01

    It is well known that paediatric patients are generally at greater risk for the development of cancer per unit of radiation dose compared with adults, due both to the longer life expectancy for any harmful effects of radiation to manifest, and the fact that developing organs and tissues are more sensitive to the effects of radiation. Multiple computed tomography (CT) examinations may cumulatively involve absorbed doses to organs and tissues that can sometimes approach or exceed the levels known from epidemiological studies to significantly increase the probability of cancer development. Radiation protection strategies include rigorous justification of CT examinations and the use of imaging techniques that are non-ionising, followed by optimisation of radiation dose exposure (according to the ‘as low as reasonably achievable’ principle). Special consideration should be given to the availability of dose reduction technology when acquiring CT scanners. Dose reduction should be optimised by adjustment of scan parameters (such as mAs, kVp, and pitch) according to patient weight or age, region scanned, and study indication (e.g. images with greater noise should be accepted if they are of sufficient diagnostic quality). Other strategies include restricting multiphase examination protocols, avoiding overlapping of scan regions, and only scanning the area in question. Newer technologies such as tube current modulation, organ-based dose modulation, and iterative reconstruction should be used when appropriate. Attention should also be paid to optimising study quality (e.g. by image post-processing to facilitate radiological diagnoses and interpretation). Finally, improving awareness through education and advocacy, and further research in paediatric radiological protection are important to help reduce patient dose.

  20. Dose in x-ray computed tomography

    Science.gov (United States)

    Kalender, Willi A.

    2014-02-01

    Radiation dose in x-ray computed tomography (CT) has become a topic of high interest due to the increasing numbers of CT examinations performed worldwide. This review aims to present an overview of current concepts for both scanner output metrics and for patient dosimetry and will comment on their strengths and weaknesses. Controversial issues such as the appropriateness of the CT dose index (CTDI) are discussed in detail. A review of approaches to patient dose assessment presently in practice, of the dose levels encountered and options for further dose optimization are also given and discussed. Patient dose assessment remains a topic for further improvement and for international consensus. All approaches presently in use are based on Monte Carlo (MC) simulations. Estimates for effective dose are established, but they are crude and not patient-specific; organ dose estimates are rarely available. Patient- and organ-specific dose estimates can be provided with adequate accuracy and independent of CTDI phantom measurements by fast MC simulations. Such information, in particular on 3D dose distributions, is important and helpful in optimization efforts. Dose optimization has been performed very successfully in recent years and even resulted in applications with effective dose values of below 1 mSv. In general, a trend towards lower dose values based on technical innovations has to be acknowledged. Effective dose values are down to clearly below 10 mSv on average, and there are a number of applications such as cardiac and pediatric CT which are performed routinely below 1 mSv on modern equipment.

  1. X-ray Computed Tomography Image Quality Indicator (IQI) Development

    Data.gov (United States)

    National Aeronautics and Space Administration — Phase one of the program is to identify suitable x-ray Computed Tomography (CT) Image Quality Indicator (IQI) design(s) that can be used to adequately capture CT...

  2. Perfusion computed tomography to assist decision making for stroke thrombolysis.

    Science.gov (United States)

    Bivard, Andrew; Levi, Christopher; Krishnamurthy, Venkatesh; McElduff, Patrick; Miteff, Ferdi; Spratt, Neil J; Bateman, Grant; Donnan, Geoffrey; Davis, Stephen; Parsons, Mark

    2015-07-01

    The use of perfusion imaging to guide selection of patients for stroke thrombolysis remains controversial because of lack of supportive phase three clinical trial evidence. We aimed to measure the outcomes for patients treated with intravenous recombinant tissue plasminogen activator (rtPA) at a comprehensive stroke care facility where perfusion computed tomography was routinely used for thrombolysis eligibility decision assistance. Our overall hypothesis was that patients with 'target' mismatch on perfusion computed tomography would have improved outcomes with rtPA. This was a prospective cohort study of consecutive ischaemic stroke patients who fulfilled standard clinical/non-contrast computed tomography eligibility criteria for treatment with intravenous rtPA, but for whom perfusion computed tomography was used to guide the final treatment decision. The 'real-time' perfusion computed tomography assessments were qualitative; a large perfusion computed tomography ischaemic core, or lack of significant perfusion lesion-core mismatch were considered relative exclusion criteria for thrombolysis. Specific volumetric perfusion computed tomography criteria were not used for the treatment decision. The primary analysis compared 3-month modified Rankin Scale in treated versus untreated patients after 'off-line' (post-treatment) quantitative volumetric perfusion computed tomography eligibility assessment based on presence or absence of 'target' perfusion lesion-core mismatch (mismatch ratio >1.8 and volume >15 ml, core computed tomography-selected rtPA-treated patients to an Australian historical cohort of non-contrast computed tomography-selected rtPA-treated patients. Of 635 patients with acute ischaemic stroke eligible for rtPA by standard criteria, thrombolysis was given to 366 patients, with 269 excluded based on visual real-time perfusion computed tomography assessment. After off-line quantitative perfusion computed tomography classification: 253 treated patients and

  3. Computed tomography of the head in neurological examination of children

    International Nuclear Information System (INIS)

    Baeckman, E.; Egg-Olofsson, O.; Raadberg, C.

    1980-01-01

    A total of 247 children from the departments of pediatrics and neurosurgery were examined with computed tomography of the head during a two year period in 1977-78. Pathological changes were demonstrated in 79 per cent. Supplementary neuro-radiological examination - angiography and encephalography - was necessary in 17 per cent. Computed tomography together with the clinical assessment frequently suffices for final diagnosis. Computed tomography greatly reduces the need for previously used neurological examinations including skull radiography. Complications may ensure because of over-sensitivity to intravenously administered contrast medium in connection with anesthesia, and the radiation dose particularly to the crystalline lens of the eye must be taken into account. Computed tomography should therefore be used only on strict indications after careful scrutiny of the case history and the status. (author)

  4. Time Domain Terahertz Axial Computed Tomography Non Destructive Evaluation Project

    Data.gov (United States)

    National Aeronautics and Space Administration — We propose to demonstrate key elements of feasibility for a high speed automated time domain terahertz computed axial tomography (TD-THz CT) non destructive...

  5. Detection of Foreign Bodies by Spiral Computed Tomography and Cone Beam Computed Tomography in Maxillofacial Regions

    Directory of Open Access Journals (Sweden)

    Farzaneh Kaviani

    2014-09-01

    Full Text Available Background and aims. The imaging techniques commonly used for foreign body detection include plain radiography, xeroradiography, computed tomography (CT scans, magnetic resonance imaging (MRI and ultrasonography. The aim of the present study was to compare cone-beam computed tomography (CBCT with conventional CT scan in determination of the exact location of a foreign body in the maxillofacial area in vitro. Materials and methods. In this descriptive study, seven different materials were selected as foreign bodies with dimen-sions of approximately 2 mm, 1 mm, and 0.5 mm. These materials consisted of metal, glass, wood, stone, plastic, graphite and tooth. These foreign bodies were placed in a sheep head between the corpus of the mandible and muscle, in the tongue and in an air space. One conventional CT scan and two CBCT scans were made on the models. Results. Tooth, metal, stone and glass foreign bodies were seen clearly on CT and CBCT scans made by NewTom at the smallest size in air. However, CBCT scan by NewTom was a more effective technique for visualization of foreign bodies in air compared to conventional CT. Foreign bodies measuring 0.5 mm made of metal, stone, glass, graphite and teeth were detected by all devices in muscle tissue and adjacent bone. Conclusion. According to the results, CBCT scans of NewTom and Planmeca are appropriate tools for detecting foreign bodies with relative high density in the maxillofacial area.

  6. Comparative dosimetry of dental cone beam computed tomography, panoramic radiography, and multislice computed tomography

    International Nuclear Information System (INIS)

    Sezgin, O.S.; Kayipmaz, S.; Yasar, D.; Yilmaz, A.B.; Ozturk, M.H.

    2012-01-01

    The aim of this study was to compare the effective organ doses from cone beam computed tomography (CBCT), multislice computed tomography (MSCT), and panoramic radiography. The tissue-absorbed doses for the Kodak 9500 CBCT system, NewTom FP CBCT system, Morita Veraviewepocs panoramic X-ray device, and Somatom Sensation 16 MSCT system were calculated using thermoluminescent dosimeter chips placed at selected locations on a radiation analog dosimetry phantom. The tissue weighting factors recommended by the International Commission on Radiological Protection in 2007 were used to obtain effective doses. The effective doses from the CBCT systems were 118.65, 84.45, and 75.43 μSv for the Kodak 9500 large field of view (FOV), NewTom FP, and Kodak 9500 medium FOV, respectively. The effective doses were 11.37 μSv for the panoramic X-ray examination, 583.73 μSv for the MSCT ''Dental'' protocol, and 1983.89 μSv for the MSCT ''NeckThinSlice'' protocol. The doses from CBCT are not sufficiently low to allow its use as a routine imaging technique instead of panoramic radiography. The FOV size should be chosen carefully to prevent excessive exposure of the patient to radiation. The use of MSCT in dentistry is associated with much radiation and should be avoided in cases where CBCT is adequate for 3D evaluation. (author)

  7. Comparison of 18F-fluorodeoxyglucose positron emission tomography/computed tomography, hydro-stomach computed tomography, and their combination for detecting primary gastric cancer

    International Nuclear Information System (INIS)

    Jang, Hye Young; Chung, Woo Suk; Song, E Rang; Kim, Jin Suk

    2015-01-01

    To retrospectively compare the diagnostic accuracy for detecting primary gastric cancer on positron emission tomography/computed tomography (PET/CT) and hydro-stomach CT (S-CT) and determine whether the combination of the two techniques improves diagnostic performance. A total of 253 patients with pathologically proven primary gastric cancer underwent PET/CT and S-CT for the preoperative evaluation. Two radiologists independently reviewed the three sets (PET/CT set, S-CT set, and the combined set) of PET/CT and S-CT in a random order. They graded the likelihood for the presence of primary gastric cancer based on a 4-point scale. The diagnostic accuracy of the PET/CT set, the S-CT set, and the combined set were determined by the area under the alternative-free receiver operating characteristic curve, and sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were calculated. Diagnostic accuracy, sensitivity, and NPV for detecting all gastric cancers and early gastric cancers (EGCs) were significantly higher with the combined set than those with the PET/CT and S-CT sets. Specificity and PPV were significantly higher with the PET/CT set than those with the combined and S-CT set for detecting all gastric cancers and EGCs. The combination of PET/CT and S-CT is more accurate than S-CT alone, particularly for detecting EGCs.

  8. Comparison of {sup 18}F-fluorodeoxyglucose positron emission tomography/computed tomography, hydro-stomach computed tomography, and their combination for detecting primary gastric cancer

    Energy Technology Data Exchange (ETDEWEB)

    Jang, Hye Young; Chung, Woo Suk; Song, E Rang; Kim, Jin Suk [Konyang University Myunggok Medical Research Institute, Konyang University Hospital, Konyang University College of Medicine, Daejeon (Korea, Republic of)

    2015-01-15

    To retrospectively compare the diagnostic accuracy for detecting primary gastric cancer on positron emission tomography/computed tomography (PET/CT) and hydro-stomach CT (S-CT) and determine whether the combination of the two techniques improves diagnostic performance. A total of 253 patients with pathologically proven primary gastric cancer underwent PET/CT and S-CT for the preoperative evaluation. Two radiologists independently reviewed the three sets (PET/CT set, S-CT set, and the combined set) of PET/CT and S-CT in a random order. They graded the likelihood for the presence of primary gastric cancer based on a 4-point scale. The diagnostic accuracy of the PET/CT set, the S-CT set, and the combined set were determined by the area under the alternative-free receiver operating characteristic curve, and sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were calculated. Diagnostic accuracy, sensitivity, and NPV for detecting all gastric cancers and early gastric cancers (EGCs) were significantly higher with the combined set than those with the PET/CT and S-CT sets. Specificity and PPV were significantly higher with the PET/CT set than those with the combined and S-CT set for detecting all gastric cancers and EGCs. The combination of PET/CT and S-CT is more accurate than S-CT alone, particularly for detecting EGCs.

  9. Pulmonary artery aneurysm in Bechcet's disease: helical computed tomography study

    International Nuclear Information System (INIS)

    Munoz, J.; Caballero, P.; Olivera, M. J.; Cajal, M. L.; Caniego, J. L.

    2000-01-01

    Behcet's disease is a vasculitis of unknown etiology that affects arteries and veins of different sizes and can be associated with pulmonary artery aneurysms. We report the case of a patient with Behcet's disease and a pulmonary artery aneurysm who was studied by means of plain chest X ray, helical computed tomography and pulmonary arteriography. Helical computed tomography is a reliable technique for the diagnosis and follow-up of these patients. (Author) 9 refs

  10. Pleuropancreatic fistula: endoscopic retrograde cholangiopancreatography and computed tomography

    International Nuclear Information System (INIS)

    McCarthy, S.; Pellegrini, C.A.; Moss, A.A.; Way, L.W.

    1984-01-01

    The complementary use of endoscopic retrograde cholangiopancreatography and computed tomography in the diagnosis and management of pleuropancreatic fistulas is described in relation to four cases in which computed tomography revealedthe thoracic extension of a pancreatic fistula not demonstrable by endoscopic retrograde cholangiopancreatography, although the latter indicated an abnormal pancreatic duct. The complementary use of both techniques may be necessary to define the pathologic anatomy so that the appropriate therapy, particularly the surgical approach, can be decided

  11. Cone beam computed tomography in Endodontics - a review.

    Science.gov (United States)

    Patel, S; Durack, C; Abella, F; Shemesh, H; Roig, M; Lemberg, K

    2015-01-01

    Cone beam computed tomography (CBCT) produces undistorted three-dimensional information of the maxillofacial skeleton, including the teeth and their surrounding tissues with a lower effective radiation dose than computed tomography. The aim of this paper is to: (i) review the current literature on the applications and limitations of CBCT; (ii) make recommendations for the use of CBCT in Endodontics; (iii) highlight areas of further research of CBCT in Endodontics. © 2014 International Endodontic Journal. Published by John Wiley & Sons Ltd.

  12. Computed Tomography - "The Changing Role of Maxillofacial Imaging"

    Directory of Open Access Journals (Sweden)

    Ambika Gupta

    2005-01-01

    Full Text Available The past three decades have witnessed great advances in the field of diagnostic imaging. Many of these advances have greatly facilitated the diagnosis and treatment of a number of maxillofacial disorders. These modalities while employing different physical principles, are often complimentary, providing valuable information about different aspects of a given disease process. Computed Tomography, 3-D Computed Tomography, and Magnetic Resonance Imaging are some such valuable adjuncts, which have opened new dimensions in the diagnosis of maxillofacial disorders.

  13. Myocardial perfusion with multi-detector computed tomography: quantitative evaluation

    International Nuclear Information System (INIS)

    Carrascosa, Patricia M.; Vallejos, J.; Capunay, Carlos M.; Deviggiano, A.; Carrascosa, Jorge M.

    2007-01-01

    The objective of this work is to evaluate the skill of multidetector computer tomography, to quantify the different patterns of intensification during the evaluation of the myocardial perfusion. 45 patients were studied with suspicion of cardiovascular disease. Multi-detector computed tomography was utilized on patients at rest and in effort with pharmacological stress, after the administration of dipyridamole. Also they were evaluated using nuclear medicine [es

  14. Comparing staging by positron emission tomography with contrast-enhanced computed tomography and by pathology in head and neck squamous cell carcinoma.

    Science.gov (United States)

    Qualliotine, J R; Mydlarz, W K; Chan, J Y K; Zhou, X; Wang, H; Agrawal, N

    2015-12-01

    This study aimed to evaluate the ability of positron emission tomography with contrast-enhanced computed tomography to correctly stage head and neck squamous cell carcinomas, in comparison with pathological staging. Positron emission tomography computed tomography was used to determine the tumour-node-metastasis classification and overall cancer stage in 85 head and neck squamous cell carcinoma patients who underwent pre-operative imaging using this modality and primary surgery between July 2010 and January 2013. Staging by positron emission tomography computed tomography was retrospectively compared with staging using pathological specimens. Agreement between imaging stage and pathological stage was examined by univariate and multivariate analysis both overall and for each primary tumour site. This imaging modality was 87.5 per cent sensitive and 44.8 per cent specific in identifying regional cervical metastases, and had false positive and false negative rates of 18.8 per cent and 8.2 per cent, respectively. The positive predictive and negative predictive values were 75.4 per cent and 65.0 per cent, respectively. Univariate and multivariate analyses revealed a significant agreement between positron emission tomography computed tomography and pathological node classification in older patients and for the oral cavity primary tumour site. There was significant agreement between both methods in the overall classification only for tumours classified as T3 or greater. Positron emission tomography computed tomography should be used with caution for the pre-operative staging of head and neck cancers because of its high false positive and false negative rates.

  15. DIAGNOSTIC ROLE OF FLUORINE-18 (18F) FLUORODEOXYGLUCOSE POSITRON EMISSION TOMOGRAPHY COMPUTED TOMOGRAPHY IN DETECTING RECURRENT DISEASE IN PATIENTS WITH COLORECTAL CANCER AND ELEVATED CARCINOEMBRYONIC ANTIGEN.

    Science.gov (United States)

    Matovina, Emil; Mihailović, Jasna; Nikoletić, Katarina; Srbovan, Dolores

    2015-01-01

    Early detection of recurrence is an important factor for long term survival of patients with colorectal cancer. Measurement of serum levels of carcinoembryonic antigen has been commonly used in the postoperative surveillance of colorectal cancer. The purpose of this study was to evaluate the ability of positron emission tomography-computed tomography to detect pathological substrate of elevated serum carcinoembryonic antigen in patients with colorectal cancer. The patients with colorectal cancer who underwent curative surgical resection and/ or chemotherapy, who were found in our database, were analyzed retrospectively. Forty-eight 18F-fluorodeoxyglucose positron emission tomography-computed tomography studies including 45 patients (14 women, 31 men; mean age: 62.93 years) with elevated serum, carcinoembryonic antigen levels, which had been performed between January 2011 and January 2014, were evaluated. Serum levels of carcinoembryonic antigen were measured within 3 months after positron emission tomography-computed tomography examination. Final diagnosis of recurrence was made by histopathological findings, radiology studies or clinical follow-up. Recurrences were diagnosed in 37 patients, the prevalence being 77.1%. Liver metastases were found in 18 patients, abdominal, pelvic and/or mediastinal lymph nodes were positive in 19 patients, 11 patients had loco regional recurrences and 4 patients had pulmonary metastasis, and bone metastases were found in one patient. One patient was diagnosed with metastasis in scar tissue. The overall sensitivity and specificity of positron emission tomography-computed tomography was 90.24% and 71.42%, respectively. The positive and negative predictive values were 94.87% and 55.56%, respectively. 18F-fluorodeoxyglucose positron emission tomography-computed tomography is a powerful tool that could be used in determining colorectal cancer recurrence in patients with elevated carcinoembryonic antigen levels and could have an

  16. [18F]Fluorodeoxyglucose (FDG)-Positron Emission Tomography (PET)/Computed Tomography (CT) in Suspected Recurrent Breast Cancer

    DEFF Research Database (Denmark)

    Hildebrandt, Malene Grubbe; Gerke, Oke; Baun, Christina

    2016-01-01

    PURPOSE: To prospectively investigate the diagnostic accuracy of [(18)F]fluorodeoxyglucose (FDG)-positron emission tomography (PET)/computed tomography (CT) with dual-time-point imaging, contrast-enhanced CT (ceCT), and bone scintigraphy (BS) in patients with suspected breast cancer recurrence....... PATIENTS AND METHODS: One hundred women with suspected recurrence of breast cancer underwent 1-hour and 3-hour FDG-PET/CT, ceCT, and BS within approximately 10 days. The study was powered to estimate the precision of the individual imaging tests. Images were visually interpreted using a four......-point assessment scale, and readers were blinded to other test results. The reference standard was biopsy along with treatment decisions and clinical follow-up (median, 17 months). RESULTS: FDG-PET/CT resulted in no false negatives and fewer false positives than the other imaging techniques. Accuracy of results...

  17. Lynch Syndrome Associated Colon Adenocarcinoma Resembling Lymphoma on Fluoro-Deoxyglucose-Positron Emission Tomography/Computed Tomography

    International Nuclear Information System (INIS)

    Aparici, Carina Mari; Win, Aung Zaw

    2015-01-01

    The patient was a 46-year-old Asian male diagnosed with lynch syndrome associated colon adenocarcinoma in the right ascending colon. A presurgical staging 18-fluoro-deoxyglucose-positron emission tomography/computed tomography (FDG-PET/CT) found increased metabolic activity in the cervical, axillary, mediastinal, supraclavicular, para-aortic and mesenteric lymph nodes. This pattern of metastasis was very unusual for lynch syndrome associated colon adenocarcinoma and the involvement of those lymph nodes resembles the pattern of spread of lymphoma. He underwent right hemicolectomy and he was subsequently treated with 12 cycles of folinic acid (leucovorin), fluorouracil (5-FU), irinotecan. A restaging FDG-PET/CT at the end of the chemotherapy showed interval decrease in size and metabolic activity in the affected lymph nodes. FDG-PET/CT is a useful imaging modality in following-up the treatment response in colon adenocarcinoma

  18. Relationship of computed tomography perfusion and positron emission tomography to tumour progression in malignant glioma

    International Nuclear Information System (INIS)

    Yeung, Timothy P C; Yartsev, Slav; Lee, Ting-Yim; Wong, Eugene; He, Wenqing; Fisher, Barbara; VanderSpek, Lauren L; Macdonald, David; Bauman, Glenn

    2014-01-01

    Introduction: This study aimed to explore the potential for computed tomography (CT) perfusion and 18-Fluorodeoxyglucose positron emission tomography (FDG-PET) in predicting sites of future progressive tumour on a voxel-by-voxel basis after radiotherapy and chemotherapy. Methods: Ten patients underwent pre-radiotherapy magnetic resonance (MR), FDG-PET and CT perfusion near the end of radiotherapy and repeated post-radiotherapy follow-up MR scans. The relationships between these images and tumour progression were assessed using logistic regression. Cross-validation with receiver operating characteristic (ROC) analysis was used to assess the value of these images in predicting sites of tumour progression. Results: Pre-radiotherapy MR-defined gross tumour; near-end-of-radiotherapy CT-defined enhancing lesion; CT perfusion blood flow (BF), blood volume (BV) and permeability-surface area (PS) product; FDG-PET standard uptake value (SUV); and SUV:BF showed significant associations with tumour progression on follow-up MR imaging (P < 0.0001). The mean sensitivity (±standard deviation), specificity and area under the ROC curve (AUC) of PS were 0.64 ± 0.15, 0.74 ± 0.07 and 0.72 ± 0.12 respectively. This mean AUC was higher than that of the pre-radiotherapy MR-defined gross tumour and near-end-of-radiotherapy CT-defined enhancing lesion (both AUCs = 0.6 ± 0.1, P ≤ 0.03). The multivariate model using BF, BV, PS and SUV had a mean AUC of 0.8 ± 0.1, but this was not significantly higher than the PS only model. Conclusion: PS is the single best predictor of tumour progression when compared to other parameters, but voxel-based prediction based on logistic regression had modest sensitivity and specificity

  19. Role of positron emission tomography-computed tomography in endometrial cancer

    Science.gov (United States)

    Erdemoğlu, Evrim; Çerçi, Sevim Süreyya; Erdemoğlu, Ebru; Yalçın, Yakup; Tatar, Burak

    2017-01-01

    Objective: The efficacy of preoperative 18F-fluoro-D-glucose (18F-FDG) positron emission tomography-computed tomography (PET-CT) in endometrium cancer is controversial. We examined the efficacy of PET-CT and the association between maximum standardized uptake value (SUVmax) and prognostic factors in endometrial cancer. Materials and Methods: Thirty patients with endometrial cancer underwent preoperative 18F-FDG/PET-CT. The patients were treated with abdominal hysterectomy with bilateral salpingo-oophorectomy, and bilateral systemic pelvic lymphadenectomy was planned for all patients; paraaortic lymphadenectomy was performed in patients with intermediate and high risk. Tumor histology, grade, depth of myometrial invasion, maximum tumor diameter, lymphovascular invasion, nodal status, and ovarian/adnexal metastases were recorded. Results: The mean primary tumor diameter was reported smaller in PET-CT and the effect size of PET-CT was -0.60. The kappa value was 0.06 for myometrial invasion. Pelvic lymph node metastasis was reported in 22.2% of patients in PET-CT. However, 3.7% of patients had pelvic lymph node metastasis. The kappa value for pelvic lymph node metastasis was 0.23, and sensitivity, specificity, and positive and negative predictive values were 100%, 80.7%, 16.6%, and 100%, respectively. Paraaortic lymph node metastasis in PET-CT was suspected in 10%. However, paraaortic lymph node metastasis was found in 6.7% in histopathologic analyses. The kappa value was 0.15. The sensitivity, specificity, and positive and negative predictive values of PET-CT for detecting paraaortic lymph node metastases were 100%, 93.7%, 66.6%, and 100%, respectively. Myometrial invasion and tumor diameter were the only important prognostic factors affecting SUVmax. Conclusion: According to our results, PET-CT has a limited role and diagnostic efficacy in endometrial cancer. The indications of FDG/PET-CT in endometrium cancer should be studied further and revised. PMID:29379661

  20. Relationship of computed tomography perfusion and positron emission tomography to tumour progression in malignant glioma

    Energy Technology Data Exchange (ETDEWEB)

    Yeung, Timothy P C [London Regional Cancer Program, London Health Sciences Centre, Ontario, Canada, N6A 4L6 (Canada); Robarts Research Institute, The University of Western Ontario, Ontario, Canada, N6A 5B7 (Canada); Department of Medical Biophysics, The University of Western Ontario, Ontario, Canada, N6A 5C1 (Canada); Yartsev, Slav [London Regional Cancer Program, London Health Sciences Centre, Ontario, Canada, N6A 4L6 (Canada); Department of Medical Biophysics, The University of Western Ontario, Ontario, Canada, N6A 5C1 (Canada); Department of Oncology, The University of Western Ontario, London Health Sciences Centre, London Regional Cancer Program, Ontario, Canada, N6A 4L6 (Canada); Lee, Ting-Yim [Robarts Research Institute, The University of Western Ontario, Ontario, Canada, N6A 5B7 (Canada); Department of Medical Biophysics, The University of Western Ontario, Ontario, Canada, N6A 5C1 (Canada); Department of Oncology, The University of Western Ontario, London Health Sciences Centre, London Regional Cancer Program, Ontario, Canada, N6A 4L6 (Canada); Department of Medical Imaging, The University of Western Ontario, London Health Sciences Centre, Victoria Hospital, Ontario, Canada, N6A 5W9 (Australia); Lawson Health Research Institute, St. Joseph' s Health Care London, Ontario, Canada, N6A 4V2 (Canada); Wong, Eugene [London Regional Cancer Program, London Health Sciences Centre, Ontario, Canada, N6A 4L6 (Canada); Department of Oncology, The University of Western Ontario, London Health Sciences Centre, London Regional Cancer Program, Ontario, Canada, N6A 4L6 (Canada); Department of Physics and Astronomy, The University of Western Ontario, Ontario, Canada, N6A 3K7 (Canada); He, Wenqing [Department of Statistical and Actuarial Sciences, The University of Western Ontario, Ontario, Canada, N6A 5B7 (Canada); Fisher, Barbara; VanderSpek, Lauren L [London Regional Cancer Program, London Health Sciences Centre, Ontario, Canada, N6A 4L6 (Canada); Department of Oncology, The University of Western Ontario, London Health Sciences Centre, London Regional Cancer Program, Ontario, Canada, N6A 4L6 (Canada); Macdonald, David [London Regional Cancer Program, London Health Sciences Centre, Ontario, Canada, N6A 4L6 (Canada); Department of Oncology, The University of Western Ontario, London Health Sciences Centre, London Regional Cancer Program, Ontario, Canada, N6A 4L6 (Canada); Department of Clinical Neurological Sciences, The University of Western Ontario, London Health Sciences Centre, University Hospital, Ontario, Canada, N6A 5A5 (Canada); Bauman, Glenn, E-mail: glenn.bauman@lhsc.on.ca [London Regional Cancer Program, London Health Sciences Centre, Ontario, Canada, N6A 4L6 (Canada); Department of Medical Biophysics, The University of Western Ontario, Ontario, Canada, N6A 5C1 (Canada); Department of Oncology, The University of Western Ontario, London Health Sciences Centre, London Regional Cancer Program, Ontario, Canada, N6A 4L6 (Canada)

    2014-02-15

    Introduction: This study aimed to explore the potential for computed tomography (CT) perfusion and 18-Fluorodeoxyglucose positron emission tomography (FDG-PET) in predicting sites of future progressive tumour on a voxel-by-voxel basis after radiotherapy and chemotherapy. Methods: Ten patients underwent pre-radiotherapy magnetic resonance (MR), FDG-PET and CT perfusion near the end of radiotherapy and repeated post-radiotherapy follow-up MR scans. The relationships between these images and tumour progression were assessed using logistic regression. Cross-validation with receiver operating characteristic (ROC) analysis was used to assess the value of these images in predicting sites of tumour progression. Results: Pre-radiotherapy MR-defined gross tumour; near-end-of-radiotherapy CT-defined enhancing lesion; CT perfusion blood flow (BF), blood volume (BV) and permeability-surface area (PS) product; FDG-PET standard uptake value (SUV); and SUV:BF showed significant associations with tumour progression on follow-up MR imaging (P < 0.0001). The mean sensitivity (±standard deviation), specificity and area under the ROC curve (AUC) of PS were 0.64 ± 0.15, 0.74 ± 0.07 and 0.72 ± 0.12 respectively. This mean AUC was higher than that of the pre-radiotherapy MR-defined gross tumour and near-end-of-radiotherapy CT-defined enhancing lesion (both AUCs = 0.6 ± 0.1, P ≤ 0.03). The multivariate model using BF, BV, PS and SUV had a mean AUC of 0.8 ± 0.1, but this was not significantly higher than the PS only model. Conclusion: PS is the single best predictor of tumour progression when compared to other parameters, but voxel-based prediction based on logistic regression had modest sensitivity and specificity.

  1. [18F]2-fluoro-2-deoxyglucose positron emission tomography/computed tomography in predicting radiation pneumonitis.

    Science.gov (United States)

    Song, Hao; Yu, Jin-ming; Kong, Feng-ming; Lu, Jie; Bai, Tong; Ma, Li; Fu, Zheng

    2009-06-05

    Prevention is presently the only available method to limit radiation-induced lung morbidity. A good predictor is the key point of prevention. This study aimed to investigate if [(18)F]2-fluoro-2-deoxyglucose (FDG) uptake changes in the lung after radiotherapy could be used as a new predictor for acute radiation pneumonitis (RP). Forty-one patients with lung cancer underwent FDG positron emission tomography/computed tomography (FDG-PET/CT) imaging before and after radiotherapy. The mean standardized uptake value (SUV) was measured for the isodose regions of 0 - 9 Gy, 10 - 19 Gy, 20 - 29 Gy, 30 - 39 Gy, 40 - 49 Gy. The mean SUV of these regions after radiotherapy was compared with baseline. The mean SUV in patients who developed RP was also compared with that in those who did not. The statistical difference was determined by matched pair t test. The Radiation Therapy Oncology Group (RTOG) criteria were used for diagnosis and grading of RP. With a median follow-up of 12 months, 11 (26.8%) of the 41 patients developed grade 2 and above acute RP. The mean SUV of regions (10 - 19 Gy, 20 - 29 Gy, 30 - 39 Gy, 40 - 49 Gy) increased after radiation therapy in all 41 patients. The mean SUVs after radiation therapy were 0.54, 0.68, 1.31, 1.74 and 2.27 for 0 - 9 Gy, 10 - 19 Gy, 20 - 29 Gy, 30 - 39 Gy and 40 - 49 Gy, respectively. Before the radiation therapy, the mean SUV in each region was 0.53, 0.52, 0.52, 0.53 and 0.54, respectively. These patients had significantly higher FDG activities in regions receiving 10 Gy or more (P acute RP subsequently. The mean SUV of the lung tissue may be a useful predictor for the acute RP. FDG-PET/CT may play a new role in the study of the radiation damage of the lung.

  2. Value of positron emission tomography and computer tomography (PET/CT) for urologic malignancies

    International Nuclear Information System (INIS)

    Boujelbene, N.; Mirimanoff, R.O.; Ozsahin, M.; Zouhair, A.; Prior, J.O.; Boubaker, A.; Azria, D.; Schaffer, M.; Gez, E.; Jichlinski, P.; Meuwly, J.Y.

    2011-01-01

    Positron emission tomography is a functional imaging technique that allows the detection of the regional metabolic rate, and is often coupled with other morphological imaging technique such as computed tomography. The rationale for its use is based on the clearly demonstrated fact that functional changes in tumor processes happen before morphological changes. Its introduction to the clinical practice added a new dimension in conventional imaging techniques. This review presents the current and proposed indications of the use of positron emission/computed tomography for prostate, bladder and testes, and the potential role of this exam in radiotherapy planning. (authors)

  3. The role of computed tomography after emergent trauma operation.

    Science.gov (United States)

    Matsushima, Kazuhide; Inaba, Kenji; Dollbaum, Ryan; Khor, Desmond; Jhaveri, Vidhi; Jimenez, Omar; Strumwasser, Aaron; Demetriades, Demetrios

    2016-12-01

    Although computed tomography (CT) has become the preferred diagnostic modality, immediate surgical intervention is often required for severely injured patients with minimum preoperative radiographic evaluation. The utility of postoperative CT (postop-CT) for the identification of undiagnosed injuries and its impact on patient management remain unclear. The purpose of this study was to evaluate the utility of postop-CT for the identification of clinically significant injuries in patients who underwent an emergent life-saving procedure. A 5-y retrospective study from 2009 to 2013 was conducted at a high-volume level I trauma center. We included blunt and penetrating trauma patients who underwent an emergent operation (neck exploration, thoracotomy, and laparotomy) without preoperative CT. Postop-CT was obtained within 48 h after the initial operation at the discretion of the attending trauma surgeon. Characteristics of newly diagnosed injuries on postop-CT were analyzed. These injuries were considered clinically significant when the patient required (1) immediate intervention; (2) new consultation from a specialty service; or (3) a higher level of care. A total of 89 patients met our inclusion criteria (five neck explorations, 16 thoracotomies, and 74 laparotomies) with the following characteristics: median age of 30 y, 87.6% male, 47.2% penetrating injury, and median injury severity score of 24. New injuries were identified on postop-CT in 59 cases (66%), and clinical management was changed in 51 cases (57%). Patients with an admission Glasgow Coma Scale undergoing an emergent operation before having their full diagnostic workup completed, postop-CT often demonstrates clinically significant injuries. Further prospective study to identify the patients who will benefit from postop-CT is warranted. Copyright © 2016 Elsevier Inc. All rights reserved.

  4. Detection of root perforations using conventional and digital intraoral radiography, multidetector computed tomography and cone beam computed tomography

    OpenAIRE

    Shokri, Abbas; Eskandarloo, Amir; Noruzi-Gangachin, Maruf; Khajeh, Samira

    2014-01-01

    Objectives This study aimed to compare the accuracy of conventional intraoral (CI) radiography, photostimulable phosphor (PSP) radiography, cone beam computed tomography (CBCT) and multidetector computed tomography (MDCT) for detection of strip and root perforations in endodontically treated teeth. Materials and Methods Mesial and distal roots of 72 recently extracted molar were endodontically prepared. Perforations were created in 0.2, 0.3, or 0.4 mm diameter around the furcation o...

  5. Computed tomography of the orbital tumors

    International Nuclear Information System (INIS)

    Choi, Jai Korl; Lee, Hwang Bok; Kang, Eun Young; Seol, Hae Young; Suh, Won Hyuck; Ahn, Byeong Yeob

    1987-01-01

    The development of computed tomography (CT) provided a noninvasive safe technique for imaging the orbit in any plane exquisitely demonstrating its normal anatomy as well as its pathologic process. The orbit is an ideal structure to be examined by CT because of large difference of absorption values between the intraorbital fat, muscle, optic nerve and vessels. In this study, the authors reviewed CT findings of 66 pathologically proven orbital tumors and tumorous conditions among the total of 98 cases who had taken orbital CT scan because if exophthalmos, ocular pain, diplopia and other ophthalmologic symptoms suggesting orbital masses during the period of 3 years. For the analysis of characteristic CT findings of the orbital lesions, all lesions are divided into 4 groups according to the site of origin, i.e., tumors arising in the eyeball (group 1); from intraconal space (group 2); from extraconal space (group 3); and from extraorbital regions (group 4). The results are as follows; 1.Extra tumor detection and localization was possible in 63 cases. Thus the detection rate was 95% with CT scan. 2.Among 36 males and 30 females, their age ranged from 10 months to 72 years. 3.Intraocular tumors (group 1) were 10 cases. Retinoblastoma occurred wholly in the young children under 5 years and combined with calcification in 57%. Choroidal melanoma occurred wholly in adults. 4.Intraconal tumors (group 2) were 9 cases. Vascular tumors (7 cases) were the most frequent and well enhancing mass. 5.The tumors arising in the extraconal region (group 3) were pseudotumor (12 cases), lymphoma (3 cases), dermoid cyst (4 cases), metastasis (2 cases), adenoid cystic carcinoma (1 case) and teratoma (1 case). A case of lymphoma demonstrating retrobulbar ill defined mass with scleral l thickening could not be differentiated from the pseudotumor which showing similar finding. 6.The lesions arising from extraorbital region (group 4) were PNS cancer (9 cases), mucocele (3 cases), lid cancer (4

  6. Usefulness of computed tomography enteroclysis in the intestinal tract

    International Nuclear Information System (INIS)

    Onoda, Hideko; Shimizu, Kensaku; Washida, Yasuo; Matsunaga, Naofumi; Higaki, Shingo; Hashimoto, Shinichi; Matsunaga, Takaharu; Sakaida, Isao

    2010-01-01

    The aim of this study was to evaluate computed tomography enteroclysis (CTE) of the small intestinal tract. A total of 36 patients underwent CTE for further examination of small intestinal disease. The indications were obscure gastrointestinal bleeding (OGIB) (n=16), suspected Crohn's disease (n=7), suspected and diagnosed by exclusion a small intestinal tumor (n=5), and others (n=8). Regarding OGIB, positive findings were observed in nine patients: angiodysplasia (n=2), suspected ileac tumor (n=2), colon cancer (n=1), colon diverticulosis and diverticulitis (n=2), Crohn's disease (n=1), and enteritis (n=1). As for Crohn's disease, hyperplasia of the small intestinal wall was shown in six patents. Positive findings of a small intestinal tumor were observed in two patients. In the 'others' category, colon diverticulitis was found in three patients and isolated dissection of the superior mesenteric artery in one of four patients with abdominal pain. Primary carcinoid was identified in the pancreas in one patient, with liver carcinoid metastasis in the remaining four patients. CT enteroclysis is a noninvasive method and useful approach in the diagnosis of small intestinal diseases. (author)

  7. Comparison of polytomography and computed tomography for fracture assessment

    International Nuclear Information System (INIS)

    Kuong, S.J.; Williamson, D.S.; Baker, N.D.; Sosman, J.L.; Nawfel, R.D.; Weissman, B.N.

    1999-01-01

    Objective. To compare polytomography (PT) and computed tomography (CT) for visualizing fractures and arthrodeses, with and without metal hardware, to determine whether CT could adequately replace PT.Design and patients. An ex vivo bovine model containing fractures in three planes, reduced with metal hardware, was created to compare fractures using PT and CT. The radiation dose at the skin surface was calculated for both examinations. For in vivo assessment, images of 14 patients who underwent both PT and CT (15 fractures, five arthrodeses) were coded, sorted, and independently read by four musculoskeletal radiologists. They rated the degree of certainty of their assessment. Time factors for patients and personnel and financial costs were also compared.Results. In the ex vivo model the fractures were well seen on both PT and CT. The radiation dose was higher for PT than for CT. In vivo, the degree of certainty in assessment of fractures and arthrodeses was higher for PT than CT in studies in which metal hardware was present, but there was no significant difference in studies without metal hardware or in the combined (with and without hardware) studies. The patient's and technologist's time required to perform a PT examination was greater than that for CT.Conclusion. In the assessment of fractures and arthrodeses containing metal hardware, PT is recommended. For studies without hardware, CT is equivalent and can replace PT. (orig.)

  8. Perfusion computed tomography evaluation of angiogenesis in liver cancer.

    Science.gov (United States)

    Yang, Han Feng; Du, Yong; Ni, Jia Xiang; Zhou, Xiang Ping; Li, Jin Dong; Zhang, Qing; Xu, Xiao Xue; Li, Yang

    2010-06-01

    To investigate the value of computed tomography (CT) perfusion imaging for assessment of angiogenesis in liver cancer. Twenty-one patients with histologically proven liver cancer underwent CT perfusion examination. We compared the following perfusion parameters in the tumour area versus the non-tumour area: total blood flow (TBF), hepatic arterial perfusion (HAP), hepatic portal perfusion (HPP) and hepatic arterial perfusion index (HAPI). Slices of postoperative specimen were stained with haematoxylin-eosin and anti-CD34 immunohistochemistry. The slices were evaluated with emphasis on the CD34-positive neovasculature in the tumour parenchyma. Tumour microvascular density (MVD) was calculated according to the Weidner method. Pearson correlation was used to detect correlations between tumour MVD and tumour perfusion parameters. TBF and HPP in the tumour area were lower than in the non-tumour area (P HAP and HAPI in the tumour area were higher than those of the non-tumour area (P HAP in the tumour area correlated with MVD in the tumour (P cancer. TBF or HAP may be a useful parameter in assessing angiogenesis of liver cancer.

  9. Pancreatic Carcinosarcoma: A Case Report Highlighting Computed Tomography Characteristics.

    Science.gov (United States)

    Mszyco, Steven; Teng, Leslie; Annunziata, Joseph; Hartman, Matthew S

    Primary pancreatic carcinosarcoma is a rare and malignant neoplasm arising within the pancreas. With fewer than a dozen cases ever reported, the recognition and treatment of this rare phenomenon can be difficult. We describe the case of an 85-year-old man who presented with vague right upper quadrant and epigastric abdominal pain and was found to have a pancreatic mass on ultrasound and computed tomography. The patient underwent open pancreaticoduodenectomy and was found to have pancreatic carcinosarcoma on microscopic evaluation. Although specific radiologic diagnosis of this entity is not possible, bringing the possibility of primary pancreatic carcinosarcoma to the ordering clinician׳s attention has the potential to hasten treatment and improve patient outcomes. We review the current literature on this rare type of neoplasia, considering histopathologic and clinical features. This case highlights the importance of radiologist awareness of this rare neoplasm and to consider carcinosarcoma in the differential when presented with a mixed solid and cystic pancreatic mass. Copyright © 2017 Elsevier Inc. All rights reserved.

  10. Predicting Neck Abscess with Contrast-Enhanced Computed Tomography

    Directory of Open Access Journals (Sweden)

    Melisa Lim Seer Yee

    2014-01-01

    Full Text Available Neck abscesses are difficult to diagnose and treat. Currently, contrast-enhanced computed tomography (CECT is the imaging modality of choice. The study aims to determine the predictive value of CECT findings in diagnosing neck abscess, causes of neck abscess and the most common neck space involved in the local population. 84 consecutive patients clinically suspected to have neck abscess who underwent CECT and surgical confirmation of pus were included. Demographic and clinical data were recorded. 75 patients were diagnosed as having neck abscess on CECT; out of those 71 patients were found to have pus. Overall CECT findings were found to have a high sensitivity (98.6% and positive predictive value (PPV (94.7% but lower specificity (67.2% in diagnosing neck abscess. The CECT diagnostic criterion with the highest PPV is the presence of rim irregularity (96%. The most common deep neck space involved is the submandibular compartment, which correlates with the finding that odontogenic cause was the most common identifiable cause of abscess in the study population. Thus, in a patient clinically suspected of having neck abscess, CECT findings of a hypodense mass with rim irregularity are helpful in confirming the diagnosis and guiding clinical management.

  11. Computed tomography and nonoperative treatment for blunt abdominal trauma

    International Nuclear Information System (INIS)

    Watanabe, Shinsuke; Ishi, Takashi; Kamachi, Masahiro; Takahashi, Toshio.

    1990-01-01

    Studies were undertaken to determine if computed tomography (CT) could reliably assist physical examination in the initial assessment of blunt abdominal trauma, and also to examine how various abdominal injuries were managed with the guidance of CT. A total of 255 patients underwent emergency abdominal CT following blunt abdominal trauma over a period of seven years. One hundred and fifty two patients had abnormal CT scans, including 58 hepatic, 36 renal, 25 splenic and 9 pancreatic injuries as well as 67 patients with intra-abdominal hemorrhage and 21 patients with free abdominal air. A comparative study on the detection of pneumoperitoneum revealed CT to be far superior to plain radiography. One hundred and three patients had normal CT scans, all of whom were managed nonoperatively, except for three false-negative cases and two nontherapeutic cases. The patients with injury to the parenchymal organs were given nonoperative treatment if they had stable vital signs and no evidence of associated injuries demanding immediate surgery and the majority of these patients were managed well nonoperatively. CT was thus found to be a useful adjunct in the management of victims of blunt abdominal trauma, since in a rapid and noninvasive fashion, CT accurately defined the extent of parenchymal organ injury and also disclosed any other abdominal injuries. (author)

  12. Computed tomography findings in patients with mild head trauma

    International Nuclear Information System (INIS)

    Sanei Taheri, M.; Hemadi, H.; Sajadinasab, M.; Sharifi, G.; Jalali, A. H.; Shakiba, M.

    2007-01-01

    To determine the frequency of computed tomography (CT) findings in patients with mild head trauma. Patients and Methods: In this cross-sectional study conducted between September 2005 and April 2006, 708 patients with mild head trauma as defined by a Glasgow Coma Score (GCS) of 13-15, were underwent standard clinical examination and cranial CT. Results The mean±SD age of our patients was 26.8±19.03 years (range: 1 month to 89 years). 489 (68.9%) patients were male and 219 (30.8%) were female. GSC was 13 in 1%. 14 in 4.6% and 15 in 94.4% of patients. The most common mechanism of trauma was car accident and falling down, each of which happened for 132 patients (18.6%). The most common findings on CT were subgaleal hematomas in 213(30%) and intracranial lesions were seen in 41 patients(5.8%) :among them 37 were male. Among intracranial lesions, the most common finding was epidural hematoma in 18 patients followed by hemorrhagic contusion in 13 patients. lntracranial lesions were observed in 28.6% of patients with GCS of 13: in 15.25% with GCS of 14 and in 5.1% with GCS of 15 (P=.002). conclusion: Many of patients with GCS equal to 15 after head trauma have considerable intracranial and minor focal neurologic signs revealed by careful physical examination could be a good marker of these lesions

  13. Multidetector-row computed tomography management of acute pulmonary embolism

    International Nuclear Information System (INIS)

    Yasui, Takahiro; Tanabe, Nobuhiro; Terada, Jiro

    2007-01-01

    The purpose of this study was to evaluate the usefulness and safety of multidetector-row computed tomography (MDCT) pulmonary angiography and indirect venography management of acute pulmonary embolism (PE), including indication for inferior vena cava (IVC) filter. Seventy-one consecutive patients who were clinically suspected of PE and underwent 16-slice MDCT pulmonary angiography and indirect venography were enrolled. Management included indication of IVC filter for patients with extensive deep venous thrombosis (DVT) in submassive or massive PE. A right ventricular to left ventricular short-axis diameter by MDCT >1.0 was judged as submassive PE. All patients were followed for 1 year. MDCT identified 50 patients with venous thromboembolism and 47 patients had acute PE: 4 were judged as massive, 14 as submassive, and 29 as non-massive by MDCT; 3 patients had DVT alone and 7 patients had caval or iliac DVT. Only 1 patient with massive PE and DVT near the right atrium died of recurrence. No other patients died of PE. Management based on MDCT pulmonary angiography combined with indirect venography is considered to be safe and reliable in patients with suspected acute PE. (author)

  14. Preoperative computer tomography evaluation in transcatheter aortic valve replacement (TAVI)

    International Nuclear Information System (INIS)

    Groudeva, V.; Stoynova, V.; Trendafilova, D.; Dzhorgova, Y.; Nachev, G.

    2014-01-01

    Transcatheter aortic valve replacement is rapidly emerging technique alternative to surgery in high risk patients. Imaging and especially computer tomography is important in preoperative assessment of the aortic ring and the prosthetic valve choice. The aim of this study is to share authors initial experience in CT assessment of the aortic ring prior to Transcatheter aortic valve replacement. 49 patients (mean age 76,55) underwent 320 rows MDCT (Acquilon One) prior TAVI. Protocol involved scanning from thoracic inlet to common femoral arteries. Aortic root size, aortic diameter at the level of coronary sinuses and the sinotubular junction and distance to coronary ostia were evaluated on a Vitrea work station. MDCT established maximal aortic ring diameter from 18 to 31 mm mean 25,04 mm while the lesser rate was from 16 to 21 mm. Accordingly positioned prostheses were in 34,75% No. 23, in 49% - No. 26 and in16,3% - No. 29. MDCT is crucial in aortic valve assessment prior to TAVI in experienced hands and multidisciplinary team. (authors) Key words: TRANSCATHETER AORTIC VALVE REPLACEMENT (TAVI). MDCT AORTIC VALVE ASSESSMENT

  15. Accuracy of computed tomography findings in acute pericarditis.

    Science.gov (United States)

    Hammer, Mark M; Raptis, Constantine A; Javidan-Nejad, Cylen; Bhalla, Sanjeev

    2014-12-01

    Acute pericarditis is a close clinical mimic of pulmonary embolism (PE) in the emergency department, and thus many of these patients are evaluated with chest computed tomography (CT). To study whether CT findings can be diagnostic of acute pericarditis. Using the electronic medical record, we retrospectively identified 46 cases of acute pericarditis and 46 control patients with pericardial effusions due to volume overload, all of whom underwent CT examination. Cases were reviewed by two blinded academic thoracic radiologists. The majority, 67%, of the pericarditis cases were evaluated with PE-protocol CTs. Pericardial thickening/enhancement was the most accurate single parameter for pericarditis, with sensitivity of 54-59% and specificity of 91-96%. CT findings, while not sensitive for pericarditis, are diagnostic, with few false-positives. Radiologists should be attentive to pericardial thickening or enhancement on CT studies done for chest pain, as they may be able to suggest pericarditis as an alternative diagnosis for the chest pain. © The Foundation Acta Radiologica 2013 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

  16. Coronary revascularization treatment based on dual-source computed tomography

    International Nuclear Information System (INIS)

    Dikkers, R.; Willems, T.P.; Jonge, G.J. de; Zaag-Loonen, H.J. van der; Ooijen, P.M.A. van; Oudkerk, M.; Piers, L.H.; Tio, R.A.; Zijlstra, F.

    2008-01-01

    Therapy advice based on dual-source computed tomography (DSCT) in comparison with coronary angiography (CAG) was investigated and the results evaluated after 1-year follow-up. Thirty-three consecutive patients (mean age 61.9 years) underwent DSCT and CAG and were evaluated independently. In an expert reading (the ''gold standard''), CAG and DSCT examinations were evaluated simultaneously by an experienced radiologist and cardiologist. Based on the presence of significant stenosis and current guidelines, therapy advice was given by all readers blinded from the results of other readings and clinical information. Patients were treated based on a multidisciplinary team evaluation including all clinical information. In comparison with the gold standard, CAG had a higher specificity (91%) and positive predictive value (PPV) (95%) compared with DSCT (82% and 91%, respectively). DSCT had a higher sensitivity (96%) and negative predictive value (NPV) (89%) compared with CAG (91% and 83%, respectively). The DSCT-based therapy advice did not lead to any patient being denied the revascularization they needed according to the multidisciplinary team evaluation. During follow-up, two patients needed additional revascularization. The high NPV for DSCT for revascularization assessment indicates that DSCT could be safely used to select patients benefiting from medical therapy only. (orig.)

  17. An industrial demonstration of computer assisted tomography

    International Nuclear Information System (INIS)

    Lupton, L.R.

    1985-09-01

    Computerized tomography (CT) is a nondestructive testing technique for generating quantitative density (linear attenuation coefficient) maps of a cross section through an object. By using a series of parallel tomographic images taken at different elevations, a three-dimensional (3-D) map of the object can be obtained. To demonstrate the power of tomography, a 3-D region of a motorcycle carburetor has been imaged using twenty-four parallel two-dimensional images. From these data, new images in planes orthogonal to the original planes have been generated, thereby improving the user's ability to visualize the position of components within the carburetor. The data have also been used to demonstrate the relationship between tomography and radiography

  18. Comparison of computed tomography with radionuclide tomography in chest diagnosis

    International Nuclear Information System (INIS)

    Takayama, Makoto; Katsuyama, Naofumi; Kawakami, Kenji; Tada, Shimpei

    1979-01-01

    Abnormal accumulation of 67 Ga citrate detected by RI tomoscan, PHO/CON, was compared with the findings of CT image by ACTA 0100 in intrathoracic diseases. Diagnostic efficacy of the RI tomoscan and CT on anatomical localization of the lesion detected by both methods were discussed. Comparative study was performed in 30 cases with malignant tumor of the lung and the mediastinum; 12 cases of primary lung cancer, 6 cases of metastatic lung cancer, 2 cases of malignant lymphoma and 10 others. Eighteen of the 30 cases showed definite evidence of enlarged mediastinal lymph nodes and/or hilar lymph nodes either by chest plain film, chest tomography or CT. Localization of 67 Ga deposit was divided into 3 groups; 1) mediastinal region, 2) hilar region and 3) lung field. The localization of lesions in each group was compared with the findings of CT image. The findings by both methods were well correlated in all cases but one. The RI tomoscan, PHO/CON, can facilitate the localization of 67 Ga accumulation by tomographic manner, and it appears to be possible to identify anatomically subdivided mediastinal lymph node groups by the combined study of RI tomoscan and CT. (author)

  19. Spectrum of single photon emission computed tomography/computed tomography findings in patients with parathyroid adenomas.

    Science.gov (United States)

    Chakraborty, Dhritiman; Mittal, Bhagwant Rai; Harisankar, Chidambaram Natrajan Balasubramanian; Bhattacharya, Anish; Bhadada, Sanjay

    2011-01-01

    Primary hyperparathyroidism results from excessive parathyroid hormone secretion. Approximately 85% of all cases of primary hyperparathyroidism are caused by a single parathyroid adenoma; 10-15% of the cases are caused by parathyroid hyperplasia. Parathyroid carcinoma accounts for approximately 3-4% of cases of primary disease. Technetium-99m-sestamibi (MIBI), the current scintigraphic procedure of choice for preoperative parathyroid localization, can be performed in various ways. The "single-isotope, double-phase technique" is based on the fact that MIBI washes out more rapidly from the thyroid than from abnormal parathyroid tissue. However, not all parathyroid lesions retain MIBI and not all thyroid tissue washes out quickly, and subtraction imaging is helpful. Single photon emission computed tomography (SPECT) provides information for localizing parathyroid lesions, differentiating thyroid from parathyroid lesions, and detecting and localizing ectopic parathyroid lesions. Addition of CT with SPECT improves the sensitivity. This pictorial assay demonstrates various SPECT/CT patterns observed in parathyroid scintigraphy.

  20. Quantification of respiration-induced esophageal tumor motion using fiducial markers and four-dimensional computed tomography

    NARCIS (Netherlands)

    Jin, Peng; Hulshof, Maarten C. C. M.; de Jong, Rianne; van Hooft, Jeanin E.; Bel, Arjan; Alderliesten, Tanja

    2016-01-01

    Respiration-induced tumor motion is an important geometrical uncertainty in esophageal cancer radiation therapy. The aim of this study was to quantify this motion using fiducial markers and four-dimensional computed tomography (4DCT). Twenty esophageal cancer patients underwent endoscopy-guided

  1. Artifacts in orthodontic bracket systems in cone-beam computed tomography and multislice computed tomography.

    Science.gov (United States)

    Hirschinger, V; Hanke, S; Hirschfelder, U; Hofmann, E

    2015-03-01

    The purpose of this study was to quantify artifacts caused by different bracket systems in cone-beam computed tomography (CBCT) and multislice computed tomography (MSCT) scans. Orthodontic brackets of four different systems were consecutively bonded to the surface of a residual molar on a human cadaveric mandible. One MSCT system and three CBCT units were used to scan each of the four bonded brackets, in addition to obtaining a blank reference scan of the tooth surface. All datasets were registered to the reference dataset using visualization software (Analyze 11.0® by AnalyzeDirect). Artifact-related reductions in image quality were expressed in percent of theoretical maximum standard deviations (SD) obtained for the gray values of the adjacent voxels, with higher percentages correlating more pronounced artifacts. Both the SD percentages for three defined line profiles and their mean values were almost invariably higher with the MSCT system than with the CBCT units. Looking into the individual SD percentages, two of the CBCT units (Pax Zenith 3D® and Picasso Trio®; both Vatech) produced higher values than the MSCT system (SOMATOM Definition AS+®; Siemens) in some line profiles. The titanium bracket, in particular, was associated with marked differences between the two scanner technologies, as the mean artifact intensities from this bracket were particularly high with the MSCT unit and relatively low with the CBCT units. The artifact intensities observed with the other three bracket systems varied widely depending on which scanner was used. Different artifact intensities were noted depending on the composition of the bracket system and on the scanner technology (MSCT/CBCT). While the artifacts manifested themselves differently with different scanners, their adverse effects were comparable. However, given the variable severity of the artifacts observed depending on the materials scanned and the scanners used, a blanket recommendation for or against MSCT or CBCT

  2. Computed tomography (CT) of orbital cellulitis

    Energy Technology Data Exchange (ETDEWEB)

    Nakashima, H.; Hara, K.; Okamura, R.; Watanabe, T.; Nagata, M. (Kumamoto Univ. (Japan). School of Medicine)

    1981-12-01

    Two cases of orbital cellulitis showed a tumor-like shadow in the orbit on CT examination. Abnormal shadows were also noticed in both cases in the frontal and ethmoid sinuses. Postoperatively, one case was diagnosed as pyocele of the frontal sinus, the other as sinusitis with subperitoneal hematoma. In these diagnoses, plane skull X-P, tomography and CT scanning were valuable.

  3. Computed Tomography Angiography with a 192-slice Dual-source Computed Tomography System: Improvements in Image Quality and Radiation Dose.

    Science.gov (United States)

    Linsen, Philip V M; Coenen, Adriaan; Lubbers, Marisa M; Dijkshoorn, Marcel L; Ouhlous, Mohamed; Nieman, Koen

    2016-01-01

    This study aims to compare image quality, radiation dose, and the influence of the heart rate on image quality of high-pitch spiral coronary computed tomography angiography (CCTA) using 128-slice (second generation) dual-source CT (DSCT) and a 192-slice DSCT (third generation) scanner. Two consecutive cohorts of fifty patients underwent CCTA by high-pitch spiral scan mode using 128 or 192-slice DSCT. The 192-slice DSCT system has a more powerful roentgen tube (2 × 120 kW) that allows CCTA acquisition at lower tube voltages, wider longitudinal coverage for faster table speed (732 m/s), and the use of iterative reconstruction. Objective image quality was measured as the signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR). Subjective image quality was evaluated using a Likert scale. While the effective dose was lower with 192-slice DSCT (1.2 ± 0.5 vs. 0.6 ± 0.3 mSv; P quality was scored higher (4.2 ± 0.8 vs. 3.0 ± 0.7; P quality, despite a higher average heart rate, at lower radiation doses compared to 128-slice DSCT.

  4. Development of a proton Computed Tomography Detector System

    Energy Technology Data Exchange (ETDEWEB)

    Naimuddin, Md. [Delhi U.; Coutrakon, G. [Northern Illinois U.; Blazey, G. [Northern Illinois U.; Boi, S. [Northern Illinois U.; Dyshkant, A. [Northern Illinois U.; Erdelyi, B. [Northern Illinois U.; Hedin, D. [Northern Illinois U.; Johnson, E. [Northern Illinois U.; Krider, J. [Northern Illinois U.; Rukalin, V. [Northern Illinois U.; Uzunyan, S. A. [Northern Illinois U.; Zutshi, V. [Northern Illinois U.; Fordt, R. [Fermilab; Sellberg, G. [Fermilab; Rauch, J. E. [Fermilab; Roman, M. [Fermilab; Rubinov, P. [Fermilab; Wilson, P. [Fermilab

    2016-02-04

    Computer tomography is one of the most promising new methods to image abnormal tissues inside the human body. Tomography is also used to position the patient accurately before radiation therapy. Hadron therapy for treating cancer has become one of the most advantegeous and safe options. In order to fully utilize the advantages of hadron therapy, there is a necessity of performing radiography with hadrons as well. In this paper we present the development of a proton computed tomography system. Our second-generation proton tomography system consists of two upstream and two downstream trackers made up of fibers as active material and a range detector consisting of plastic scintillators. We present details of the detector system, readout electronics, and data acquisition system as well as the commissioning of the entire system. We also present preliminary results from the test beam of the range detector.

  5. Dose estimation for paediatric cranial computed tomography

    International Nuclear Information System (INIS)

    Curci Daros, K.A.; Bitelli Medeiros, R.; Curci Daros, K.A.; Oliveira Echeimberg, J. de

    2006-01-01

    In the last ten years, the number of paediatric computed tomography (CT) scans have increased worldwide, contributing to higher population radiation dose. Technique diversification in paediatrics and different CT equipment technologies have led to various exposure levels complicating precise evaluation of doses and operational conditions necessary for good quality images. The objective of this study was to establish a quantitative relationship between absorbed dose and cranial region in children up to 6 years old undergoing CT exams. Methods: X-ray was measured on the cranial surface of 64 patients undergoing CT using thermoluminescent (T.L.) dosimeters. Forty T.L.D.100 thermoluminescent dosimeters (T.L.D.) were evenly distributed on each patients skin surface along the sagittal axis. Measurements were performed in facial regions exposed to scatter radiation and in the supratentorial and posterior fossa regions, submitted to primary radiation. T.L.D. were calibrated for 120 kV X-ray over the acrylic phantom. T.L. measurements were made with a Harshaw 4000 system. Patient mean T.L. readings were determined for position, pi, of T.L.D. and normalized to the maximum supratentorial reading. From integrating the linear T.L. density function (?) resulting from radiation distribution in each of the three exposed regions, dose fraction was determined in the region of interest, along with total dose under the technical conditions used in that specific exam protocol. For each T.L.D. position along the patient cranium, there were n T.L. measurements with 2% uncertainty due to T.L. reader, and 5% due to thermal treatment of dosimeters. Also, mean T.L. readings and their uncertainties were calculated for each patient at each position, p. Results: Mean linear T.L. density for the region exposed to secondary radiation defined by position, 0.3≤p≤6 cm, was ρ((p)=7.9(4)x10 -2 +7(5)x10 -5 p 4.5(4) cm -1 ; exposed to primary X-ray for the posterior fossa region defined by position

  6. Evaluating iterative reconstruction performance in computed tomography.

    Science.gov (United States)

    Chen, Baiyu; Ramirez Giraldo, Juan Carlos; Solomon, Justin; Samei, Ehsan

    2014-12-01

    Iterative reconstruction (IR) offers notable advantages in computed tomography (CT). However, its performance characterization is complicated by its potentially nonlinear behavior, impacting performance in terms of specific tasks. This study aimed to evaluate the performance of IR with both task-specific and task-generic strategies. The performance of IR in CT was mathematically assessed with an observer model that predicted the detection accuracy in terms of the detectability index (d'). d' was calculated based on the properties of the image noise and resolution, the observer, and the detection task. The characterizations of image noise and resolution were extended to accommodate the nonlinearity of IR. A library of tasks was mathematically modeled at a range of sizes (radius 1-4 mm), contrast levels (10-100 HU), and edge profiles (sharp and soft). Unique d' values were calculated for each task with respect to five radiation exposure levels (volume CT dose index, CTDIvol: 3.4-64.8 mGy) and four reconstruction algorithms (filtered backprojection reconstruction, FBP; iterative reconstruction in imaging space, IRIS; and sinogram affirmed iterative reconstruction with strengths of 3 and 5, SAFIRE3 and SAFIRE5; all provided by Siemens Healthcare, Forchheim, Germany). The d' values were translated into the areas under the receiver operating characteristic curve (AUC) to represent human observer performance. For each task and reconstruction algorithm, a threshold dose was derived as the minimum dose required to achieve a threshold AUC of 0.9. A task-specific dose reduction potential of IR was calculated as the difference between the threshold doses for IR and FBP. A task-generic comparison was further made between IR and FBP in terms of the percent of all tasks yielding an AUC higher than the threshold. IR required less dose than FBP to achieve the threshold AUC. In general, SAFIRE5 showed the most significant dose reduction potentials (11-54 mGy, 77%-84%), followed by

  7. Dose estimation for paediatric cranial computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Curci Daros, K.A.; Bitelli Medeiros, R. [Sao Paulo Univ. Federal (Brazil); Curci Daros, K.A.; Oliveira Echeimberg, J. de [Centro Univ. Sao Camilo, Sao Paulo (Brazil)

    2006-07-01

    In the last ten years, the number of paediatric computed tomography (CT) scans have increased worldwide, contributing to higher population radiation dose. Technique diversification in paediatrics and different CT equipment technologies have led to various exposure levels complicating precise evaluation of doses and operational conditions necessary for good quality images. The objective of this study was to establish a quantitative relationship between absorbed dose and cranial region in children up to 6 years old undergoing CT exams. Methods: X-ray was measured on the cranial surface of 64 patients undergoing CT using thermoluminescent (T.L.) dosimeters. Forty T.L.D.100 thermoluminescent dosimeters (T.L.D.) were evenly distributed on each patients skin surface along the sagittal axis. Measurements were performed in facial regions exposed to scatter radiation and in the supratentorial and posterior fossa regions, submitted to primary radiation. T.L.D. were calibrated for 120 kV X-ray over the acrylic phantom. T.L. measurements were made with a Harshaw 4000 system. Patient mean T.L. readings were determined for position, pi, of T.L.D. and normalized to the maximum supratentorial reading. From integrating the linear T.L. density function (?) resulting from radiation distribution in each of the three exposed regions, dose fraction was determined in the region of interest, along with total dose under the technical conditions used in that specific exam protocol. For each T.L.D. position along the patient cranium, there were n T.L. measurements with 2% uncertainty due to T.L. reader, and 5% due to thermal treatment of dosimeters. Also, mean T.L. readings and their uncertainties were calculated for each patient at each position, p. Results: Mean linear T.L. density for the region exposed to secondary radiation defined by position, 0.3{<=}p{<=}6 cm, was {rho}((p)=7.9(4)x10{sup -2}+7(5)x10{sup -5}p{sup 4.5(4)} cm{sup -1}; exposed to primary X-ray for the posterior fossa

  8. Central venous catheterization for acute trauma resuscitation: Tip position analysis using routine emergency computed tomography.

    Science.gov (United States)

    Struck, Manuel F; Ewens, Sebastian; Schummer, Wolfram; Busch, Thilo; Bernhard, Michael; Fakler, Johannes K M; Stumpp, Patrick; Stehr, Sebastian N; Josten, Christoph; Wrigge, Hermann

    2018-03-01

    Central venous catheter insertion for acute trauma resuscitation may be associated with mechanical complications, but studies on the exact central venous catheter tip positions are not available. The goal of the study was to analyze central venous catheter tip positions using routine emergency computed tomography. Consecutive acute multiple trauma patients requiring large-bore thoracocervical central venous catheters in the resuscitation room of a university hospital were enrolled retrospectively from 2010 to 2015. Patients who received a routine emergency chest computed tomography were analyzed regarding central venous catheter tip position. The central venous catheter tip position was defined as correct if the catheter tip was placed less than 1 cm inside the right atrium relative to the cavoatrial junction, and the simultaneous angle of the central venous catheter tip compared with the lateral border of the superior vena cava was below 40°. During the 6-year study period, 97 patients were analyzed for the central venous catheter tip position in computed tomography. Malpositions were observed in 29 patients (29.9%). Patients with malpositioned central venous catheters presented with a higher rate of shock (systolic blood pressure central venous catheter tips. Logistic regression revealed injury severity score as a significant predictor for central venous catheter malposition (odds ratio = 1.039, 95% confidence interval = 1.005-1.074, p = 0.024). Multiple trauma patients who underwent emergency central venous catheter placement by experienced anesthetists presented with considerable tip malposition in computed tomography, which was significantly associated with a higher injury severity.

  9. Acute mediastinitis: multidetector computed tomography findings following cardiac surgery

    Energy Technology Data Exchange (ETDEWEB)

    Macedo, Clarissa Aguiar de [Universidade de Sao Paulo (USP), SP (Brazil). Faculdade de Medicina. Instituto do Coracao (InCor)]. E-mail: clarissaaguiarm@yahoo.com.br; Baena, Marcos Eduardo da Silva [Instituto do Coracao (InCor), Sao Paulo, SP (Brazil). Unit of Ultrasonography; Uezumi, Kiyomi Kato [Instituto do Coracao (InCor), Sao Paulo, SP (Brazil). Unit of Computed Tomography; Castro, Claudio Campi de [Instituto do Coracao (InCor), Sao Paulo, SP (Brazil). Unit of Magnetic Resonance Imaging; Lucarelli, Claudio Luiz [Instituto do Coracao (InCor), Sao Paulo, SP (Brazil). Center of Diagnosis; Cerri, Giovanni Guido [Universidade de Sao Paulo (USP), SP (Brazil). School of Medicine. Dept. of Radiology

    2008-07-15

    Postoperative mediastinitis is defined as an infection of the organs and tissues in the mediastinal space, with an incidence ranging between 0.4% and 5% of cases. This disease severity varies from infection of superficial tissues in the chest wall to fulminant mediastinitis with sternal involvement. Diagnostic criterion for postoperative detection of acute mediastinitis at computed tomography is the presence of fluid collections and gas in the mediastinal space, which might or might not be associated with peristernal abnormalities such as edema of soft tissues, separation of sternal segments with marginal bone resorption, sclerosis and osteomyelitis. Other associated findings include lymphadenomegaly, pulmonary consolidation and pleural/ pericardial effusion. Some of these findings, such as mediastinal gas and small fluid collections can be typically found in the absence of infection, early in the period following thoracic surgery where the effectiveness of computed tomography is limited. After approximately two weeks, computed tomography achieves almost 100% sensitivity and specificity. Patients with clinical suspicion of mediastinitis should be submitted to computed tomography for investigating the presence of fluid collections to identify the extent and nature of the disease. Multidetector computed tomography allows 3D images reconstruction, contributing particularly to the evaluation of the sternum. (author)

  10. Role of Positron Emission Tomography-Computed Tomography in the Management of Anal Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Mistrangelo, Massimiliano, E-mail: mistrangelo@katamail.com [Digestive and Colorectal Surgical Department, Centre of Minimal Invasive Surgery, University of Turin, Molinette Hospital, Turin (Italy); Pelosi, Ettore [PET Center IRMET spa, Turin (Italy); Bello, Marilena [Department of Nuclear Medicine, University of Turin, Molinette Hospital (Italy); Ricardi, Umberto [Department of Radiotherapy, University of Turin, Molinette Hospital (Italy); Milanesi, Enrica [Oncological Centre for Gastrointestinal Neoplasms, University of Turin, Molinette Hospital (Italy); Cassoni, Paola [Department of Biomedical Sciences and Human Oncology, University of Turin, Molinette Hospital (Italy); Baccega, Massimo [Department of Nuclear Medicine, Molinette Hospital (Italy); Filippini, Claudia [Anaesthesia and Intensive Care Unit, University of Turin, Molinette Hospital (Italy); Racca, Patrizia [Oncological Centre for Gastrointestinal Neoplasms, University of Turin, Molinette Hospital (Italy); Lesca, Adriana [Department of Nuclear Medicine, Molinette Hospital (Italy); Munoz, Fernando H. [Department of Radiotherapy, University of Turin, Molinette Hospital (Italy); Fora, Gianluca [Oncological Centre for Gastrointestinal Neoplasms, University of Turin, Molinette Hospital (Italy); Skanjeti, Andrea [Department of Nuclear Medicine, University of Turin, Molinette Hospital (Italy); Cravero, Francesca; Morino, Mario [Digestive and Colorectal Surgical Department, Centre of Minimal Invasive Surgery, University of Turin, Molinette Hospital, Turin (Italy)

    2012-09-01

    Purpose: Pre- and post-treatment staging of anal cancer are often inaccurate. The role of positron emission tomograpy-computed tomography (PET-CT) in anal cancer is yet to be defined. The aim of the study was to compare PET-CT with CT scan, sentinel node biopsy results of inguinal lymph nodes, and anal biopsy results in staging and in follow-up of anal cancer. Methods and Materials: Fifty-three consecutive patients diagnosed with anal cancer underwent PET-CT. Results were compared with computed tomography (CT), performed in 40 patients, and with sentinel node biopsy (SNB) (41 patients) at pretreatment workup. Early follow-up consisted of a digital rectal examination, an anoscopy, a PET-CT scan, and anal biopsies performed at 1 and 3 months after the end of treatment. Data sets were then compared. Results: At pretreatment assessment, anal cancer was identified by PET-CT in 47 patients (88.7%) and by CT in 30 patients (75%). The detection rates rose to 97.9% with PET-CT and to 82.9% with CT (P=.042) when the 5 patients who had undergone surgery prior to this assessment and whose margins were positive at histological examination were censored. Perirectal and/or pelvic nodes were considered metastatic by PET-CT in 14 of 53 patients (26.4%) and by CT in 7 of 40 patients (17.5%). SNB was superior to both PET-CT and CT in detecting inguinal lymph nodes. PET-CT upstaged 37.5% of patients and downstaged 25% of patients. Radiation fields were changed in 12.6% of patients. PET-CT at 3 months was more accurate than PET-CT at 1 month in evaluating outcomes after chemoradiation therapy treatment: sensitivity was 100% vs 66.6%, and specificity was 97.4% vs 92.5%, respectively. Median follow-up was 20.3 months. Conclusions: In this series, PET-CT detected the primary tumor more often than CT. Staging of perirectal/pelvic or inguinal lymph nodes was better with PET-CT. SNB was more accurate in staging inguinal lymph nodes.

  11. Computed tomography and radionuclide brain scanning

    International Nuclear Information System (INIS)

    Lusins, J.O.; Chayes, Z.; Nakagawa, H.

    1980-01-01

    A comparison o CT (computerized Tomography) and radionuclide brain scanning was performed; 30 patients with a total of 42 lesions were evaluated. Previous sreports have shown that CT and radionuclide scanning are equally useful in detecting metastatic disease. However, if contrast enhancement is used we find that computerized tomography is far more accurate than radionuclide scanning in detecting metastatic disease to the brain, 95.4 percent as compared to 62 percent. Our study also shows that radionuclide scanning falls off in accuracy when the the lesion is below 2 cm. in size. Also, the presence of brain edema in association with metastatic disease increases the probability of having a positive nuclear scan finding

  12. 18F-Fluorodeoxyglucose-Positron Emission Tomography/Computed Tomography in Tuberculosis: Spectrum of Manifestations.

    Science.gov (United States)

    Agarwal, Krishan Kant; Behera, Abhishek; Kumar, Rakesh; Bal, Chandrasekhar

    2017-01-01

    The objective of this article is to provide an illustrative tutorial highlighting the utility of 18 F-fluorodeoxyglucose-positron emission tomography/computed tomography ( 18 F-FDG-PET/CT) imaging to detect spectrum of manifestations in patients with tuberculosis (TB). FDG-PET/CT is a powerful tool for early diagnosis, measuring the extent of disease (staging), and consequently for evaluation of response to therapy in patients with TB.

  13. Evaluation of myocardial ischemia by multiple detector computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Fernandes, Fabio Vieira, E-mail: rccury@me.com [Hospital do Coracao (HCor), Sao Paulo, SP (Brazil); Cury, Roberto Caldeira [Hospital Samaritano, Sao Paulo, SP (Brazil)

    2015-01-15

    For years, cardiovascular diseases have been the leading cause of death worldwide, bringing on important social and economic consequences. Given this scenario, the search for a method capable of diagnosing coronary artery diseases in an early and accurate way is increasingly higher. The coronary computed tomography angiogram is already widely established for the stratification of coronary artery diseases, and, more recently, the computed tomography myocardial perfusion imaging has been providing relevant information by correlating ischemia and the coronary anatomy. The objective of this review is to describe the evaluation of myocardial ischemia by multiple detector computed tomography. This study will resort to controlled clinical trials that show the possibility of a single method to identify the atherosclerotic load, presence of coronary artery luminal narrowing and possible myocardial ischemia, by means of a fast, practical and reliable method validated by a multicenter study. (author)

  14. Diagnosis of dementia with single photon emission computed tomography

    International Nuclear Information System (INIS)

    Jagust, W.J.; Budinger, T.F.; Reed, B.R.

    1987-01-01

    Single photon emission computed tomography is a practical modality for the study of physiologic cerebral activity in vivo. We utilized single photon emission computed tomography and N-isopropyl-p-iodoamphetamine iodine 123 to evaluate regional cerebral blood flow in nine patients with Alzheimer's disease (AD), five healthy elderly control subjects, and two patients with multi-infarct dementia. We found that all subjects with AD demonstrated flow deficits in temporoparietal cortex bilaterally, and that the ratio of activity in bilateral temporoparietal cortex to activity in the whole slice allowed the differentiation of all patients with AD from both the controls and from the patients with multi-infarct dementia. Furthermore, this ratio showed a strong correlation with disease severity in the AD group. Single photon emission computed tomography appears to be useful in the differential diagnosis of dementia and reflects clinical features of the disease

  15. Utility of the computed tomography indices on cone beam computed tomography images in the diagnosis of osteoporosis in women

    International Nuclear Information System (INIS)

    Koh, Kwang Joon; Kim, Kyung A

    2011-01-01

    This study evaluated the potential use of the computed tomography indices (CTI) on cone beam CT (CBCT) images for an assessment of the bone mineral density (BMD) in postmenopausal osteoporotic women. Twenty-one postmenopausal osteoporotic women and 21 postmenopausal healthy women were enrolled as the subjects. The BMD of the lumbar vertebrae and femur were calculated by dual energy X-ray absorptiometry (DXA) using a DXA scanner. The CBCT images were obtained from the unilateral mental foramen region using a PSR-9000N Dental CT system. The axial, sagittal, and coronal images were reconstructed from the block images using OnDemend3D. The new term 'CTI' on CBCT images was proposed. The relationship between the CT measurements and BMDs were assessed and the intra-observer agreement was determined. There were significant differences between the normal and osteoporotic groups in the computed tomography mandibular index superior (CTI(S)), computed tomography mandibular index inferior (CTI(I)), and computed tomography cortical index (CTCI). On the other hand, there was no difference between the groups in the computed tomography mental index (CTMI: inferior cortical width). CTI(S), CTI(I), and CTCI on the CBCT images can be used to assess the osteoporotic women.

  16. Utility of the computed tomography indices on cone beam computed tomography images in the diagnosis of osteoporosis in women

    Energy Technology Data Exchange (ETDEWEB)

    Koh, Kwang Joon; Kim, Kyung A [School of Dentistry, Chonbuk National University, Jeonju (Korea, Republic of)

    2011-09-15

    This study evaluated the potential use of the computed tomography indices (CTI) on cone beam CT (CBCT) images for an assessment of the bone mineral density (BMD) in postmenopausal osteoporotic women. Twenty-one postmenopausal osteoporotic women and 21 postmenopausal healthy women were enrolled as the subjects. The BMD of the lumbar vertebrae and femur were calculated by dual energy X-ray absorptiometry (DXA) using a DXA scanner. The CBCT images were obtained from the unilateral mental foramen region using a PSR-9000N Dental CT system. The axial, sagittal, and coronal images were reconstructed from the block images using OnDemend3D. The new term 'CTI' on CBCT images was proposed. The relationship between the CT measurements and BMDs were assessed and the intra-observer agreement was determined. There were significant differences between the normal and osteoporotic groups in the computed tomography mandibular index superior (CTI(S)), computed tomography mandibular index inferior (CTI(I)), and computed tomography cortical index (CTCI). On the other hand, there was no difference between the groups in the computed tomography mental index (CTMI: inferior cortical width). CTI(S), CTI(I), and CTCI on the CBCT images can be used to assess the osteoporotic women.

  17. Microstructure of cotton fibrous assemblies based on computed tomography

    Science.gov (United States)

    Jing, Hui; Yu, Weidong

    2017-12-01

    This paper describes for the first time the analysis of inner microstructure of cotton fibrous assemblies using computed tomography. Microstructure parameters such as packing density, fractal dimension as well as porosity including open porosity, closed porosity and total porosity are calculated based on 2D data from computed tomography. Values of packing density and fractal dimension are stable in random oriented fibrous assemblies, and there exists a satisfactory approximate linear relationship between them. Moreover, poles analysis indicates that porosity represents the tightness of fibrous assemblies and open poles are main existence.

  18. Computed tomography of the thorax in children with cystic fibrosis

    International Nuclear Information System (INIS)

    Parente Filho, Livio William Sales; Marchiori, Edson; Daltro, Pedro; Santos, Eloa Nunes

    1998-01-01

    We studied retrospectively the value of computed tomography of the thorax in patients suffering from cystic fibrosis. Twenty-six patients were studied, which showed as the most frequency pulmonary findings bronchial wall thickening in 22 patients (84.6), followed by bronchiectasis in 16 patients (61.5%). Less frequent finding were ill-defined patch consolidation, mucoid impaction, bullaes and atelectasis. We found a predominant distribution of bronchial wall thickening and bronchiectasis in the upper lobes of the lungs. Computed tomography is the more sensitive technique for early visualization and location of the manifestations of cystic fibrosis bronchopathy. (author)

  19. Helical computed tomography and the workstation: introduction to a symbiosis

    International Nuclear Information System (INIS)

    Garcia-Santos, J.M.

    1997-01-01

    We do a brief introduction to the possibilities of an helical computed tomography system when it is associated with a powerful workstation. The fast and volumetric way of acquisition constitutes, basically, the main advantage of this sort of computed tomography. The anatomical and radio pathological study, in a workstation, of the acquired information (thanks to multiplanar and 3D reconstruction), increases significantly our capacity of analysis in each patient. Only the clinical and radiological experience will tell us which is the right place that this symbiosis occupies within our diagnosis tools. (Author) 11 refs

  20. Reducing image noise in computed tomography (CT) colonography: effect of an integrated circuit CT detector.

    Science.gov (United States)

    Liu, Yu; Leng, Shuai; Michalak, Gregory J; Vrieze, Thomas J; Duan, Xinhui; Qu, Mingliang; Shiung, Maria M; McCollough, Cynthia H; Fletcher, Joel G

    2014-01-01

    To investigate whether the integrated circuit (IC) detector results in reduced noise in computed tomography (CT) colonography (CTC). Three hundred sixty-six consecutive patients underwent clinically indicated CTC using the same CT scanner system, except for a difference in CT detectors (IC or conventional). Image noise, patient size, and scanner radiation output (volume CT dose index) were quantitatively compared between patient cohorts using each detector system, with separate comparisons for the abdomen and pelvis. For the abdomen and pelvis, despite significantly larger patient sizes in the IC detector cohort (both P noise was significantly lower (both P 0.18). Based on the observed image noise reduction, radiation dose could alternatively be reduced by approximately 20% to result in similar levels of image noise. Computed tomography colonography images acquired using the IC detector had significantly lower noise than images acquired using the conventional detector. This noise reduction can permit further radiation dose reduction in CTC.

  1. Ultrasound compared with computed tomography and pancreatic arteriography in the detection of endocrine tumours of the pancreas

    International Nuclear Information System (INIS)

    Paeivaensalo, M.; Maekaeraeinen, H.; Siniluoto, T.; Staahlberg, M.; Jalovaara, P.; Oulu Univ. Central Hospital

    1989-01-01

    We have evaluated ultrasound, computed tomography and arteriographic findings in 15 patients with 17 endocrine pancreatic tumours having a mean diameter of 2.3 cm (range 1-7 cm). All patients underwent computed tomography, and all but one ultrasound and arteriography. Ultrasound was the initial investigation in 11 patients, and identified 10 of the 16 tumours present in 14 patients. Two tumours were found at ultrasound reexamination after having been identified by other radiological methods. Computed tomography revealed 8 out of 17 tumours, while arteriography identified 8 out of 16 tumours. Computed tomography was the initial investigation in 4 patients,and identified one tumour. In only 4 patients were tumours not detected by any of the imaging methods. The sensitivities of ultrasound, computed tomography and arteriography in the detection of pancreatic tumours were 62.5% (95% confidence interval 50.4-74.6%), 47.1% (95% confidence interval 35.0-59.2%), and 50.0% (95% confidence interval 37.5-62.5%), respectively. Ultrasound was thus more accurate than computed tomography or arteriography in detecting endocrine pancreatic tumours, and should be the initial radiological investigation. (orig.)

  2. Application and development of Industrial Computed Tomography in China

    International Nuclear Information System (INIS)

    Kong Fangeng; Xian Wu

    1996-01-01

    Compared with traditional perspective radiography, ICT (Industrial Computed Tomography) is able to acquire tomography image without the disadvantages of image overlapping and blurring that exist in traditional perspective radiography. By acquiring the 2D tomography image of the object at different stage as many as needed, it is possible to achieve 3D tomography image. In China, the first Γ-ray ICT equipment was born at Chongqing University in May 1993. For this equipment, 60 Co radiation source with 1 Ci and 30 Ci was used, and spatial resolution is about 0.5mm, and density resolution is about 0.5%, and the diameter of the test object can be 300mm, but the price of the Chinese ICT equipment is only about a half on the same type of ICT equipment producing abroad other than China. Besides Γ-ray ICT, Chinese are engaging in research and develop x-ray ICT to meet foreign and domestic need. (author)

  3. Indications for brain computed tomography scan after minor head injury.

    Science.gov (United States)

    Sharif-Alhoseini, Mahdi; Khodadadi, Hossein; Chardoli, Mojtaba; Rahimi-Movaghar, Vafa

    2011-10-01

    Minor head injury (MHI) is a common injury seen in Emergency Departments (ED). Computed tomography (CT) scan of the brain is a good method of investigation to diagnose intracranial lesions, but there is a disagreement about indications in MHI patients. We surveyed the post-traumatic symptoms, signs or past historical matters that can be used for the indication of brain CT scan. All patients with MHI who were older than 2 years, had a Glasgow Coma Scale (GCS) score ≥13 and were referred to the ED, underwent brain CT scan. Data on age, headache, vomiting, loss of consciousness (LOC) or amnesia, post-traumatic seizure, physical evidence of trauma above the clavicles, alcohol intoxication, and anticoagulant usage were collected. The main outcome measure was the presence of lesions related to the trauma in brain CT scan. For categorical variables, Chi-square test was used. Six hundred and forty-two patients were examined by brain CT scan after MHI, and 388 patients (60.4%) did not have any risk indicator. Twenty patients (3.1%) had abnormal brain CT scans. The logistic regression model showed that headache (P=0.006), LOC or amnesia (P=0.024) and alcohol (P=0.036) were associated with abnormal brain CT. WE SUGGESTED THAT ABNORMAL BRAIN CT SCAN RELATED TO THE TRAUMA AFTER MHI CAN BE PREDICTED BY THE PRESENCE OF ONE OR MORE OF THE FOLLOWING RISK INDICATORS: Headache, vomiting, LOC or amnesia, and alcohol intoxication. Thus, if any patient has these indicators following MHI, he must be considered as a high-risk MHI.

  4. Assessment of painful total shoulder arthroplasty using computed tomography arthrography.

    Science.gov (United States)

    Mallo, Gregory C; Burton, Lauren; Coats-Thomas, Margaret; Daniels, S David; Sinz, Nathan J; Warner, Jon J P

    2015-10-01

    This study assessed the accuracy of computed tomography (CT) arthrography when evaluating glenoid component stability in the setting of postarthroplasty shoulder pain. We retrospectively reviewed all patients presenting to the clinic during a 5.5-year period to identify those with a painful shoulder arthroplasty more than 1 year after the index procedure. We excluded reverse and hemiarthroplasty procedures, patients with a clearly identifiable cause for pain, such as rotator cuff insufficiency or gross component loosening as seen on plain radiographs, and those with culture-positive aspiration. There were 14 patients with suspected glenoid component loosening but inconclusive plain radiographs. Each of the 14 patients underwent a CT arthrogram that was evaluated by the senior author (J.J.P.W.) for the presence or absence of contrast material underneath the polyethylene component. Operative reports and surgical videos from subsequent arthroscopy were reviewed to assess glenoid component stability as determined by direct arthroscopic visualization. CT arthrography suggested glenoid component loosening in 8 of 14 patients (57.1%), and arthroscopic inspection identified loosening in 10 of 14 patients (71.4%). In 3 of 10 patients (30%), CTA suggested a well-fixed glenoid component, but gross loosening was identified during arthroscopy. In this study, CTA yielded a sensitivity of 70%, a specificity of 75%, a positive predictive value of 87.5%, and a negative predictive value of 50.0%. CTA had a low negative predictive value (50%), and therefore, the prediction of component stability based on the absence of contrast between the glenoid component and the bone-cement interface does not always reflect true stability. Copyright © 2015 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.

  5. Indications for computed tomography in patients with mild head injury

    International Nuclear Information System (INIS)

    Ono, Kenichiro; Wada, Kojiro; Takahara, Takashi; Shirotani, Toshiki

    2007-01-01

    The factors affecting outcome were analyzed in 1,064 patients, 621 males and 443 females aged 10 to 104 years (mean 46±23 years), with mild head injury (Glasgow Coma Scale [GCS] score≥14) but no neurological signs presenting within 6 hours after injury. Intracranial lesion was found in 4.7% (50/1,064), and 0.66% (7/1,064) required surgical treatment. The Japan Coma Scale (JCS) and GCS assessments were well correlated (r=0.797). Multivariate analysis revealed significant correlations between computed tomography (CT) abnormality and age≥60 years, male sex, JCS score≥1, alcohol consumption, headache, nausea/vomiting, and transient loss of consciousness (LOC)/amnesia. Univariate analysis revealed that pedestrian in a motor vehicle accident, falling from height, and mechanisms of injuries except blows were correlated to intracranial injury. No significant correlations were found between craniofacial soft tissue injury and intracranial injury. Patients with occipital impact, nonfrontal impact, or skull fracture were more likely have intracranial lesions. Bleeding tendency was not correlated with CT abnormality. The following indications were proposed for CT: JCS score>0, presence of accessory symptoms (headache, nausea/vomiting, LOC/amnesia), and age≥60 years. These criteria would reduce the frequency of CT by 29% (309/1,064). Applying these indications to subsequent patients with GCS scores 14-15, 114 of 168 patients required CT, and intracranial lesions were found in 13. Two refused CT. Fifty-four of the 168 patients did not need CT according to the indications, but 38 of the 54 patients actually underwent CT because of social reasons (n=21) or patient request (n=17). These indications for CT including JCS may be useful in the management of patients with mild head injury. (author)

  6. Feasibility Study of Computational Fluid Dynamics Simulation of Coronary Computed Tomography Angiography Based on Dual-Source Computed Tomography.

    Science.gov (United States)

    Lu, Jing; Yu, Jie; Shi, Heshui

    2017-01-01

    Adding functional features to morphological features offers a new method for non-invasive assessment of myocardial perfusion. This study aimed to explore technical routes of assessing the left coronary artery pressure gradient, wall shear stress distribution and blood flow velocity distribution, combining three-dimensional coronary model which was based on high resolution dual-source computed tomography (CT) with computational fluid dynamics (CFD) simulation. Three cases of no obvious stenosis, mild stenosis and severe stenosis in left anterior descending (LAD) were enrolled. Images acquired on dual-source CT were input into software Mimics, ICEMCFD and FLUENT to simulate pressure gradient, wall shear stress distribution and blood flow velocity distribution. Measuring coronary enhancement ratio of coronary artery was to compare with pressure gradient. Results conformed to theoretical values and showed difference between normal and abnormal samples. The study verified essential parameters and basic techniques in blood flow numerical simulation preliminarily. It was proved feasible.

  7. 18F-fluorodeoxyglucose Positron Emisson Tomography/Computed Tomography Guided Conformal Brachytherapy for Cervical Cancer

    International Nuclear Information System (INIS)

    Nam, Heerim; Huh, Seung Jae; Ju, Sang Gyu; Park, Won; Lee, Jeong Eun; Choi, Joon Young; Kim, Byung-Tae; Kim, Chan Kyo; Park, Byung Kwan

    2012-01-01

    Purpose: To evaluate the feasibility of 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET)/computed tomography (CT)-guided conformal brachytherapy treatment planning in patients with cervical cancer. Methods and Materials: Pretreatment FDG-PET/CT was performed for 12 patients with cervical cancer. Brachytherapy simulation was performed after an external-beam radiation therapy median dose of 4140 cGy. Patients underwent FDG-PET/CT scans with placement of tandem and ovoid applicators. The gross tumor volume (GTV) was determined by adjusting the window and level to a reasonable value and outlining the edge of the enhancing area, which was done in consultation with a nuclear medicine physician. A standardized uptake value profile of the tumor margin was taken for each patient relative to the maximum uptake value of each tumor and analyzed. The plan was designed to deliver 400 cGy to point A (point A plan) or to cover the clinical target volume (CTV) (PET/CT plan). Results: The median dose that encompassed 95% of the target volume (D95) of the CTV was 323.0 cGy for the point A plan vs 399.0 cGy for the PET/CT plan (P=.001). The maximum standardized uptake values (SUV max ) of the tumors were reduced by a median of 57% (range, 13%-80%). All but 1 patient presented with discernable residual uptake within the tumors. The median value of the thresholds of the tumors contoured by simple visual analysis was 41% (range, 23%-71%). Conclusions: In this study, the PET/CT plan was better than the conventional point A plan in terms of target coverage without increasing the dose to the normal tissue, making optimized 3-dimensional brachytherapy treatment planning possible. In comparison with the previously reported study with PET or CT alone, we found that visual target localization was facilitated by PET fusion on indeterminate CT masses. Further studies are needed to characterize the metabolic activity detected during radiation therapy for more reliable targeting.

  8. Industrial Computed Tomography using Proximal Algorithm

    KAUST Repository

    Zang, Guangming

    2016-04-14

    In this thesis, we present ProxiSART, a flexible proximal framework for robust 3D cone beam tomographic reconstruction based on the Simultaneous Algebraic Reconstruction Technique (SART). We derive the proximal operator for the SART algorithm and use it for minimizing the data term in a proximal algorithm. We show the flexibility of the framework by plugging in different powerful regularizers, and show its robustness in achieving better reconstruction results in the presence of noise and using fewer projections. We compare our framework to state-of-the-art methods and existing popular software tomography reconstruction packages, on both synthetic and real datasets, and show superior reconstruction quality, especially from noisy data and a small number of projections.

  9. 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

  10. Value of computed tomography pelvimetry in patients with a previous cesarean section

    International Nuclear Information System (INIS)

    Yamani, Tarik Y.; Rouzi, Abdulrahim A.

    1998-01-01

    A case-control study was conducted at the Department of Obstetrics and Gynaecology, King Abdulaziz University Hospital, Jeddah, Saudi Arabia to determine the value of computed tomography pelivimetry in patients with a previous cesarean section. Between January 1993 and December 1995, 219 pregnant women with one previous cesarean had antenatal CT pelvimetry for assessment of the pelvis. One hundred and nineteen women did not have CT pelvimetry and served as control. Fifty-one women (51%) in the CT pelvimetry group were delivered by cesarean section. Twenty-three women (23%) underwent elective cesarean section for contracted pelvis based upon the findings of CT pelvimetry and 28 women (28%) underwent emergency cesarean section after trial of labor. In the group who did not have CT pelvimetry, 26 women (21.8%) underwent emergency cesarean section. This was a statistically significant difference (P=0.02). There were no statistically significant differences in birthweight and Apgar scores either group. There was no prenatal or maternal mortality in this study. Computed tomography pelvimetry increased the rate of cesarean delivery without any benefit in the immediate delivery outcomes. Therefore, the practice of documenting the adequacy of the pelvis by CT pelvimetry before vaginal birth after cesarean should be abandoned. (author)

  11. Tracheo-oesophageal fistula diagnosed with multidetector computed tomography.

    LENUS (Irish Health Repository)

    Hodnett, Pa

    2009-04-01

    This case highlights important issues in investigation of patients with suspected tracheo-oesophageal fistula including the value of multidetector computed tomography, the importance of thorough imaging evaluation when high clinical suspicion of tracheo-oesophageal fistula exists and the value of close interaction between radiologists and intensive care physicians in the investigation of these patients.

  12. An Easily Assembled Laboratory Exercise in Computed Tomography

    Science.gov (United States)

    Mylott, Elliot; Klepetka, Ryan; Dunlap, Justin C.; Widenhorn, Ralf

    2011-01-01

    In this paper, we present a laboratory activity in computed tomography (CT) primarily composed of a photogate and a rotary motion sensor that can be assembled quickly and partially automates data collection and analysis. We use an enclosure made with a light filter that is largely opaque in the visible spectrum but mostly transparent to the near…

  13. Computed tomography of the orbit - A review and an update.

    Science.gov (United States)

    Tawfik, Hatem A; Abdelhalim, Ahmed; Elkafrawy, Mamdouh H

    2012-10-01

    Computed tomography (CT) and magnetic resonance imaging (MRI) of the orbit have been competing for the hearts and minds of health care providers for well over 2 decades. While several drawbacks pertaining to CT have been outlined since the introduction of MRI, CT remains the standard diagnostic test for evaluating cross-sectional, 2 or 3-dimensional images of the body.

  14. Multidetector computed tomography of jaw lesions in children and adolescents

    International Nuclear Information System (INIS)

    Gadodia, A.; Seith, A.; Sharma, R.; Choudhury, A.R.; Bhutia, O.; Gupta, A.

    2010-01-01

    Full text: Jaw lesions in paediatric and adolescent population are uncommon and can arise in odontogenic or non-odontogenic tissues. With the advent of multidetector computed tomography (MDCT), algorithm for imaging jaw lesions has changed dramatically. This pictorial essay describes the imaging appearance of commonly encountered jaw lesions in children and adolescents with emphasis on MDCT findings

  15. Computed tomography of the gastro-intestinal tract : its value

    International Nuclear Information System (INIS)

    Reeders, J.W.A.J.

    1995-01-01

    The subject discussed include indications and accuracy of CT - computed tomography, technical considerations, common pitfalls in CT interpretation, parameters for CT evaluation, benign lesions, double halo and target signs, hyperattenuated, inflammatory bowel disease, intestinal ischaemia, primary adenocarcinoma of the GIT, lymphoma and leiomyosarcoma (3 refs.)

  16. Radiation dosimetry of computed tomography x-ray scanners

    International Nuclear Information System (INIS)

    Poletti, J.L.; Williamson, B.D.P.; Le Heron, J.C.

    1983-01-01

    This report describes the development and application of the methods employed in National Radiation Laboratory (NRL) surveys of computed tomography x-ray scanners (CT scanners). It includes descriptions of the phantoms and equipment used, discussion of the various dose parameters measured, the principles of the various dosimetry systems employed and some indication of the doses to occupationally exposed personnel

  17. Multi-detector computed tomography radiation doses in the follow ...

    African Journals Online (AJOL)

    2014-05-09

    May 9, 2014 ... (CT) scans without prior consultation with a radiologist in order to increase efficiency in light of human resource constraints. As a result ... smart phone or mobile device to read online. Read online: Background: Multi-detector computed tomography (MDCT) is the preferred modality for follow-up of paediatric ...

  18. Computed tomography and childhood seizure disorder in Ibadan ...

    African Journals Online (AJOL)

    Background: Computed Tomography (CT) is an important tool for neuroimaging, it offers an opportunity to investigate structural lesions as a cause of seizures with little morbidity. This study is designed to evaluate it's applicability in children with epileptic seizures. Method: It is a descriptive study of the CT scans of the 103 ...

  19. A survey of computed tomography imaging techniques and patient ...

    African Journals Online (AJOL)

    Objectives: To assess the level of patient dose in Computed Tomography examination in Kenya, compare with the international diagnostic reference levels and establish the initial national diagnostic reference levels. Design: The patient doses for brain, chest, abdomen and pelvis examinations were assessed using typical ...

  20. Routine Cranial Computed Tomography before Lumbar Puncture in ...

    African Journals Online (AJOL)

    Background: Current international guidelines recommend that a cranial computed tomography (CT) be performed on all HIV-positive patients presenting with new onset seizures, before a lumbar puncture (LP) is performed. In the South African setting, however this delay could be life threatening. The present study sought to ...

  1. Computed tomography features of head injury in Ghanaian children ...

    African Journals Online (AJOL)

    Background: Injuries to the head are common in children. There are several reports in literature of head injury and evaluation with computed tomography scan (CT scan) but only a few focus on children. Method: A retrospective review of films and reports of the CT scans of 41 children with head injury. Results: Positive CT ...

  2. Documentation of the ISA Micro Computed Tomography System

    Energy Technology Data Exchange (ETDEWEB)

    Brown, William D. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Smith, Jerel A. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2013-12-18

    This document is intended to provide information on the ISA Micro Computed Tomography (MicroCT) system that will be installed in Yavne, Israel. X-ray source, detector, and motion control hardware are specified as well as specimen platforms, containers, and reference material types. Most of the details on the system are derived from Reference 1 and 2.

  3. Unsuspected organic disease in chronic schizophrenia demonstrated by computed tomography

    International Nuclear Information System (INIS)

    Cunningham Owens, D.G.; Johnstone, E.C.; Bydder, G.M.; Kreel, L.

    1980-01-01

    Unsuspected intracranial pathology was demonstrated in 12 of 136 chronic schizophrenic patients examined by computed tomography (CT). Seven cases of cerebral infarction were found, and one each of porencephalic cyst, meningioma, cystic enlargement of the pineal body, and two of subdural haematoma. Attention is drawn to the value of CT in demonstrating organic disease in schizophrenia. (author)

  4. Computed tomography evaluation of autogenous graft in sinus lift surgery

    International Nuclear Information System (INIS)

    Ajzen, Sergio Aron; Moscatiello, Rafael Andrade; Lima, Aida Maria Custodio de; Moscatiello, Vitoria Aparecida Muglia; Helio Kiitiro Yamashita; Mosacatiello, Rafael Muglia; Nishiguchi, Celso Itiro; Alves, Maria Teresa de Seixas

    2001-01-01

    The objective was to quantify bone formation within autogenous bone grafts and autogenous bone grafts in combination with platelet-rich plasma obtained either from apheresis or centrifugation using computed tomography. This prospective, double-blind study was conducted in 34 male and female adult patients (mean age of 28 years and 8 months), with either unilateral or bilateral pneumatization of the maxillary sinuses, requiring bone graft for dental implant. All patients were submitted to computed tomography examinations prior and six months after sinus lift surgery. Fifty-three maxillary sinuses were operated and divided into three distinct groups: autogenous bone graft, autogenous bone graft in combination with platelet-rich plasma obtained by centrifugation, and autogenous bone graft in combination with platelet-rich plasma obtained by apheresis. The results showed that computed tomography demonstrated bone growth in height and width between the initial and the follow-up computed tomography scans in all three groups. However, no statistical difference was found either for bone height or width. It was concluded that clinical evidence demonstrates the effectiveness of autogenous bone grafts, particularly when used in combination with bone growth factors such as platelet-rich plasma, which allow prosthetic and functional restoration of maxillofacial structures through fixation of dental implants. (author)

  5. Geometrical metrology on silicone rubber by computed tomography

    DEFF Research Database (Denmark)

    Müller, Pavel; Pacurar, Ramona Alexandra; De Chiffre, Leonardo

    2011-01-01

    Computed tomography (CT) represents a suitable measuring technique for investigation of deformable materials, since no forces are developed on the part during scanning. As for any other measuring instruments, the traceability of the CT scanners needs to be assured. An investigation on geometrical...

  6. Electron beam computed tomography for the diagnosis of cardiac ...

    African Journals Online (AJOL)

    Electron beam computed tomography (EBCT) of the heart is a new modality which will alter the way cardiology is practised. It allows for the detection of early coronary artery disease (CAD) in asymptomatic individuals, regardless of their level of risk as assessed by traditional risk factor analysis. Compared with risk analysis ...

  7. Computed tomography of von Meyenburg complex simulating micro-abscesses

    International Nuclear Information System (INIS)

    Sada, P.N.; Ramakrishna, B.

    1994-01-01

    A case is presented of a bile duct hamartoma in a 44 year old man being evaluated for abdominal pain. The computed tomography (CT) findings suggested micro-abscesses in the liver and a CT guided tru-cut biopsy showed von Meyenburg complex. 9 refs., 3 figs

  8. The utility of computed tomography for diagnosis of intraabdominal abscess

    International Nuclear Information System (INIS)

    Kohno, Kenichi; Takahashi, Toshio; Tamakawa, Yoshiharu

    1981-01-01

    Prompt treatment is necessary for postoperative intraabdominal absecss with accurate diagnosis. Computed Tomography (CT) developed as a new diagnostic imaging procedure revealed to be able to make early diagnosis of intraabdominal abscess after surgery. This paper presented six patients with intraabdominal abscess and discussed the utility of CT diagnosis of the abdominal abscess. (author)

  9. Noninvasive photoacoustic computed tomography of mouse brain metabolism in vivo

    OpenAIRE

    Yao, Junjie; Xia, Jun; Maslov, Konstantin I.; Nasiriavanaki, Mohammadreza; Tsytsarev, Vassiliy; Demchenko, Alexei V.; Wang, Lihong V.

    2012-01-01

    We have demonstrated the feasibility of imaging mouse brain metabolism using photoacoustic computed tomography (PACT), a fast, noninvasive and functional imaging modality with optical contrast and acoustic resolution. Brain responses to forepaw stimulations were imaged transdermally and transcranially. 2-NBDG, which diffuses well across the blood–brain-barrier, provided exogenous contrast for photoacoustic imaging of glucose response. Concurrently, hemoglobin provided endogenous contrast for ...

  10. Quantification of salt concentrations in cured pork by computed tomography

    DEFF Research Database (Denmark)

    Vestergaard, Christian Sylvest; Risum, Jørgen; Adler-Nissen, Jens

    2004-01-01

    Eight pork loin samples were mounted in Plexiglas cylinders and cured for five days. Samples were scanned by computed tomography (CT) once every 24 h. At the end of the experiment, the cylinders were cut in 1 cm sections and analyzed for chloride. From image analysis of the CT images, concentration...

  11. Cost-effectiveness of PET and PET/Computed Tomography

    DEFF Research Database (Denmark)

    Gerke, Oke; Hermansson, Ronnie; Hess, Søren

    2015-01-01

    measure by means of incremental cost-effectiveness ratios when considering the replacement of the standard regimen by a new diagnostic procedure. This article discusses economic assessments of PET and PET/computed tomography reported until mid-July 2014. Forty-seven studies on cancer and noncancer...

  12. Systematic Errors in Dimensional X-ray Computed Tomography

    DEFF Research Database (Denmark)

    that it is possible to compensate them. In dimensional X-ray computed tomography (CT), many physical quantities influence the final result. However, it is important to know which factors in CT measurements potentially lead to systematic errors. In this talk, typical error sources in dimensional X-ray CT are discussed...

  13. ORIGINAL ARTICLE ORIG ORIG Is computed tomography of the ...

    African Journals Online (AJOL)

    As a predictor of outcome, scores of 13 to 15 are considered to correspond with mild injury, 9 to 12 with moderate injury and 8 or lower with severe injury.1-3. Since the advent of computed tomography (CT) scans in the early. 1970s, the demand from emergency room physicians for CT scans for minor head injury patients is ...

  14. Variability of four-dimensional computed tomography patient models

    NARCIS (Netherlands)

    Sonke, Jan-Jakob; Lebesque, Joos; van Herk, Marcel

    2008-01-01

    PURPOSE: To quantify the interfractional variability in lung tumor trajectory and mean position during the course of radiation therapy. METHODS AND MATERIALS: Repeat four-dimensional (4D) cone-beam computed tomography (CBCT) scans (median, nine scans/patient) routinely acquired during the course of

  15. Quantitative 3-Dimensional Computed Tomography Measurements of Coronoid Fractures

    NARCIS (Netherlands)

    Mellema, Jos J.; Janssen, Stein J.; Guitton, Thierry G.; Ring, David

    2015-01-01

    Purpose Using quantitative 3-dimensional computed tomography (Q3DCT) modeling, we tested the null hypothesis that there was no difference in fracture fragment volume, articular surface involvement, and number of fracture fragments between coronoid fracture types and patterns of traumatic elbow

  16. Cerebral computed tomography in newborn children with large retinal hemmorrhage

    International Nuclear Information System (INIS)

    Skalpe, I.O.; Egge, K.; Maltau, J.M.

    1982-01-01

    Cerebral computed tomography was performed in 10 neonates with large retinal hemorrhage compared with a control group of 10 full-term neonates without such hemorrhage. No signs of intracranial hemorrhage were found. The cerebral ventricles were poorly visualized in both groups. Periventricular low attenuation areas was a frequent finding in both groups. (orig.)

  17. The value of computed tomography-urography in predicting the ...

    African Journals Online (AJOL)

    Background The natural course of pelviureteric junction (PUJ) obstruction is variable. Of those who require surgical intervention, there is no definite reliable preoperative predictor of the likely postoperative outcome. We evaluated the value of preoperative computed tomography (CT)-urography in predicting the ...

  18. Computed tomography: Will the slices reveal the truth

    Science.gov (United States)

    Haridas, Harish; Mohan, Abarajithan; Papisetti, Sravanthi; Ealla, Kranti K. R.

    2016-01-01

    With the advances in the field of imaging sciences, new methods have been developed in dental radiology. These include digital radiography, density analyzing methods, cone beam computed tomography (CBCT), magnetic resonance imaging, ultrasound, and nuclear imaging techniques, which provide high-resolution detailed images of oral structures. The current review aims to critically elaborate the use of CBCT in endodontics. PMID:27652253

  19. Computed Tomography Features of Spontaneously Perforated Pyometra: A Case Report

    Energy Technology Data Exchange (ETDEWEB)

    Chan, K.S.; Tan, C.K.; Mak, C.W.; Chia, C.C.; Kuo, C.Y.; Yu, W.L. [Chi-Mei Medical Center, Tainan, Taiwan (China). Depts. of Intensive Care Medicine, Radiology, Obstetrics and Gynecology, and Surgery

    2006-03-15

    Spontaneous perforation of pyometra is an extremely rare emergent gynecologic disease. We report a 73-year-old woman with a spontaneously perforated pyometra presenting with acute abdomen in the emergency department. A dedicated computed tomography examination of the abdominal and pelvic regions revealed the diagnosis. The patient recovered well after surgical intervention and antibiotic treatment.

  20. Coronary artery fly-through using electron beam computed tomography

    NARCIS (Netherlands)

    van Ooijen, P M; Oudkerk, M; van Geuns, R J; Rensing, B J; de Feyter, P J

    2000-01-01

    BACKGROUND: Virtual reality techniques have recently been introduced into clinical medicine. This study examines the possibility of coronary artery fly-through using a dataset obtained by noninvasive coronary angiography with contrast-enhanced electron-beam computed tomography. METHODS AND RESULTS:

  1. Introduction to the foundations of X-ray computed tomography

    International Nuclear Information System (INIS)

    Herman, G.T.

    1979-01-01

    The author gives a brief survey of a small fraction of the existing literature on the foundations of X-ray computed tomography. While the selection is biased by the interests of the author, taken in conjunction with the other articles in this book, it should provide the means for getting acquainted with this very active field of applicable research. (Auth.)

  2. Computer Tomography: A Novel Diagnostic Technique used in Horses

    African Journals Online (AJOL)

    In Veterinary Medicine, Computer Tomography (CT scan) is used more often in dogs and cats than in large animals due to their small size and ease of manipulation. This paper, however, illustrates the use of the technique in horses. CT scan was used in the diagnosis of two conditions of the head and limbs, namely alveolar ...

  3. Moulding process characterization of paper bottles using computed tomography

    DEFF Research Database (Denmark)

    Saxena, Prateek; Bissacco, Giuliano

    2016-01-01

    The paper presents an approach of evaluating the moulding process for production of paper bottlesusing Computed Tomography (CT). Moulded Pulp Products (MPP) are made of a formed, dewateredand dried mixture of pulp fibers and water. Modern industrial pulp moulding is datedback to the year 1903 when...

  4. Diagnosis of bilateral adrenocortical hemorrhage by computed tomography

    International Nuclear Information System (INIS)

    Liu, L.; Haskin, M.E.; Rose, L.I.; Bemis, C.E.

    1982-01-01

    Adrenocortical hemorrhage has been diagnosed on the basis of the clinical presentation and response to steroids or autopsy findings. Prompt recognition of the disease has been difficult because of its similarity to other disorders. We report the diagnosis of a bilateral adrenocortical hemorrhage by computed tomography (CT), followed by biochemical confirmation of the diagnosis

  5. ORIGINAL ARTICLE ORIG ORIG Is computed tomography of the ...

    African Journals Online (AJOL)

    Mendelow AD, Teasdale G, Jennett B, Bryden J, Hessett C, Murray G. Risks of intracranial haematoma in head injured adults. BMJ 1983; 287: 1173-1176. 16. Miller EC, Derlet RW, Kinser D. Minor head trauma: is computed tomography always necessary? Ann. Emerg Med 1996; 27: 290-294. 17. Knuckey NW, Gelbard S, ...

  6. The role of (18)fluoro-deoxyglucose positron emission tomography/computed tomography in resectable pancreatic cancer.

    Science.gov (United States)

    Crippa, Stefano; Salgarello, Matteo; Laiti, Silvia; Partelli, Stefano; Castelli, Paola; Spinelli, Antonello E; Tamburrino, Domenico; Zamboni, Giuseppe; Falconi, Massimo

    2014-08-01

    The role of (18)fluoro-deoxyglucose positron emission tomography/computed tomography in pancreatic ductal adenocarcinoma is debated. We retrospectively assessed the value of (18)fluoro-deoxyglucose positron emission tomography/computed tomography in addition to conventional imaging as a staging modality in pancreatic cancer. (18)Fluoro-deoxyglucose positron emission tomography/computed tomography was performed in 72 patients with resectable pancreatic carcinoma after multi-detector computed tomography positron emission tomography was considered positive for a maximum standardized uptake value >3. Overall, 21% of patients had a maximum standardized uptake value ≤ 3, and 60% of those had undergone neoadjuvant treatment (P=0.0001). Furthermore, 11% of patients were spared unwarranted surgery since positron emission tomography/computed tomography detected metastatic disease. All liver metastases were subsequently identified with contrast-enhanced ultrasound. Sensitivity and specificity of positron emission tomography/computed tomography for distant metastases were 78% and 100%. The median CA19.9 concentration was 48.8 U/mL for the entire cohort and 292 U/mL for metastatic patients (P=0.112). The widespread application of (18)fluoro-deoxyglucose positron emission tomography/computed tomography in patients with resectable pancreatic carcinoma seems not justified. It should be considered in selected patients at higher risk of metastatic disease (i.e. CA19.9>200 U/mL) after undergoing other imaging tests. Neoadjuvant treatment is significantly associated with low metabolic activity, limiting the value of positron emission tomography in this setting. Copyright © 2014 Editrice Gastroenterologica Italiana S.r.l. Published by Elsevier Ltd. All rights reserved.

  7. Computed tomography of the temporal horns at Alzheimer's disease

    International Nuclear Information System (INIS)

    Gerber, U.; Vogel

    1989-01-01

    In the literature there are different opinions referring to the involvement of the temporal lobes or horns at Alzheimer's disease. Conventionally computed tomogram of the head does not include the temporal horn in its full length. A simple method to demonstrate the temporal horns after cranial computer tomography is described. It allows the evaluation of temporal lobe and temporal horn if questionable alterations at Alzheimer's disease are to be discussed. (orig.) [de

  8. 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.

  9. Position emission tomography with or without computed tomography in the primary staging of Hodgkin's lymphoma

    DEFF Research Database (Denmark)

    Hutchings, Martin; Loft, Annika; Hansen, Mads

    2006-01-01

    BACKGROUND AND OBJECTIVES: In order to receive the most appropriate therapy, patients with Hodgkin's lymphoma (HL) must be accurately stratified into different prognostic staging groups. Computed tomography (CT) plays a pivotal role in the conventional staging. The aim of the present study...

  10. Computed tomography in presenile, senile dementia

    International Nuclear Information System (INIS)

    Tanabe, Norimitsu

    1981-01-01

    The author investigated the relations of brain atrophy demonstrated by computerized tomography, dementia and electroencephalogram (EEG) in presenile and senile diseases. The result revealed that the correlation of brain atrophy, when demonstrated on the basis of ventricular ratio, is more definite and higher with dementia than that when demonstrated on the ventricular width. It was also revealed that in the control group, the ventricle gets enlarged due to aging, but no such tendency was observed in the patient group. In the case of septugenarians, no significant difference was observed between the two, and the ventricular-brain ratio or the criteria of brain atrophy is 8 -- 9% in patients in their forties to fifties; 12% for those in their sixties, and more than 15% among those in their seventies. In the relation of the brain atrophy to EEG, it was revealed that EEG is closely related to dementia than is the ventricular ratio. Upon following the progress of patients with Alzheimer, it was found that dementia and brain atrophy do not progress parallel to each other, but in stages. (author)

  11. Inter laboratory comparison on Industrial Computed Tomography

    DEFF Research Database (Denmark)

    Angel, Jais Andreas Breusch; De Chiffre, Leonardo; Larsen, Erik

    The ‘CIA-CT comparison - Inter laboratory comparison on industrial Computed Tomography” is organized by DTU Department of Mechanical Engineering within the Danish project “Centre for Industrial Application of CT scanning - CIA-CT”. The project is co-financed by the Danish Ministry of Science...

  12. 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 ...

  13. Estimation of lung growth using computed tomography

    NARCIS (Netherlands)

    P.A. de Jong (Pim); Y. Nakano (Yasutaka); M.H. Lequin (Maarten); P.J.F.M. Merkus (Peter); H.A.W.M. Tiddens (Harm); J.C. Hogg (James); H.O. Coxson (Harvey)

    2003-01-01

    textabstractAnatomical studies suggest that normal lungs grow by rapid alveolar addition until about 2 yrs of age followed by a gradual increase in alveolar dimensions. The aim of this study was to examine the hypothesis that normal lung growth can be monitored by computed

  14. Computed tomography of traumatic atlantooccipital dislocation.

    Science.gov (United States)

    Gerlock, A J; Mirfakhraee, M; Benzel, E C

    1983-09-01

    Although atlantooccipital dislocation is a well-recognized radiological entity, its computed tomographic (CT) recognition has not been previously described. It is the purpose of this report to show the complementary role of CT in precisely defining the abnormalities in both the coronal and the sagittal reconstruction planes. A case is presented and the literature is reviewed.

  15. Detection of non-aggressive stage IA lung cancer using chest computed tomography and positron emission tomography/computed tomography.

    Science.gov (United States)

    Shiono, Satoshi; Yanagawa, Naoki; Abiko, Masami; Sato, Toru

    2014-10-01

    In contrast to lung cancer with ground-glass opacity, the radiological investigation of solid lung cancer has not been well examined. The aim of this study was to explore chest computed tomography (CT) and positron emission tomography (PET)/CT findings with regard to outcomes after lung cancer surgery in order to radiologically classify clinical stage IA lung cancers by tumour aggressiveness. Three hundred and fifteen clinical stage IA patients were analysed. Four groups were defined by tumour solidity on CT and by the standardized uptake value (SUV) index on PET-CT (tumour maximum SUV/mean right liver lobe SUV). We analysed the association between radiological findings and both pathological invasiveness and postoperative outcome. Group A (n = 84) had an SUV index <1.0 and non-solid tumours, Group B (n = 24) had an SUV index <1.0 and solid tumours, Group C (n = 54) had an SUV index ≥1.0 and non-solid tumours, while Group D (n = 153) had an SUV index ≥1.0 and solid tumours. Invasive lung cancer was found in 2/84 (2.4%) patients in Group A, 1/24 (4.2%) in Group B, 13/54 (24.1%) in Group C and 58/153 (37.9%) in Group D (P < 0.01). The 5-year recurrence-free rate was 100% in Groups A and B, 90.3% in C and 65.7% in D (P < 0.01). The cancer-specific survival rate was 100% in A and B, 94.6% in C and 81.7% in D (P < 0.01). The present results suggest that preoperative PET/CT and thin-section CT findings provide important information for a selection of surgical procedures for clinical stage IA lung cancers. In clinical stage IA lung cancers displaying solid or non-solid density in thin-section findings, an SUV index <1.0 may be a better criterion for detecting non-aggressive lung cancer even in solid lung cancers. © The Author 2014. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.

  16. Hypertensive crisis due to contrast-enhanced computed tomography in a patient with malignant pheochromocytoma.

    Science.gov (United States)

    Nakano, Sachiko; Tsushima, Yoshito; Taketomi-Takahashi, Ayako; Higuchi, Tetsuya; Amanuma, Makoto; Oriuchi, Noboru; Endo, Keigo

    2011-07-01

    A 63-year-old man underwent computed tomography (CT) using intravenous low-osmolar iodine contrast medium (LOCM) 6 days after undergoing high-dose (131)I-MIBG therapy for metastatic pheochromocytoma. Immediately after the CT examination, his blood pressure increased to 260/160 mmHg (from 179/101 mmHg before the examination). Phentolamine mesilate was administered, and the blood pressure rapidly went back to normal. Although hypertensive crisis after administration of LOCM is rare, this case suggests that high-dose (131)IMIBG therapy may be a risk factor for hypertensive crisis after administration of intravenous LOCM.

  17. Computed tomography as a supplement to urography in the evaluation of suspected neuroblastoma

    International Nuclear Information System (INIS)

    Siegel, M. J.; Sagel, S.S.

    1982-01-01

    Eleven children in whom a retropertioneal neuroblastoma was suspected on the basis of plain radiographic or urographic findings underwent computed tomography (CT). CT identified and localized a neurogenic tumor in eight patients. Calcifications were demonstrated by CT in six lesions, but by urography in only four. One neuroblastoma detected by CT was not seen on the urogram; in five patients greater extent of the tumor was defined by CT than by conventional radiologic procedures. In three patients CT excluded a neuroblastoma, but diagnosed other disorders (hepatic tumor, pancreatitis, and retrocaval ureter). Our results confirm that CT is a simple and accurate method for diagnosis, delineation of extent, or exclusion of neuroblastoma

  18. Computed tomography in lumbar degenerative disease

    Energy Technology Data Exchange (ETDEWEB)

    Isu, Toyohiko; Miyasaka, Kazuo; Abe, Satoru; Takei, Hidetoshi; Kaneda, Kiyoshi (Hokkaido Univ., Sapporo (Japan). School of Medicine)

    1984-02-01

    We reported the 18 patients which underwent surgical exploration and reviewed these CT findings. Method All CT scans were obtained on Somatom II, high resolution CT scanner, with the patient in the supine position. A lateral localizer image (Topogram) was used to select the appropriate intervertebral disk space. The slice thickness was 4 mm. Results 1) CT findings in lumbar degenerative diseases include bony canal stenosis (central canal stenosis, narrowed lateral recess), soft tissue abnormalities (herniated nucleus pulposus, bulging annulus, hypertrophy and/or ossification of ligamentum flavum, no delineation of nerve root in lateral recess), and spinal instability (spondylolisthesis, vacuum phenomenon). 2) The above three factors contribute to narrowing of spinal canal. 3) No delineation of nerve root or soft tissue replacement of epidural fat in lateral recess suggests that the nerve root may be compressed by some factors. 4) Herniated nucleus pulposus may cause nerve root compression with or without canal stenosis. Conclusion This study revealed that the CT findings correlated closely with the surgical findings and the site of nerve root compression could be determined.

  19. Cranial computed tomography in psychiatry. Kraniale Computertomographie in der Psychiatrie

    Energy Technology Data Exchange (ETDEWEB)

    Falkai, P. (Rheinische Landes- und Hochschulklinik Duesseldorf, Psychiatrische Klinik der Heinrich-Heine-Universitaet (Germany)); Bogerts, B. (Rheinische Landes- und Hochschulklinik Duesseldorf, Psychiatrische Klinik der Heinrich-Heine-Universitaet (Germany))

    1993-08-13

    Computed tomography has gained importance as a diagnostic tool in psychiatry to exclude structural brain pathology, but has passed on its role in research to magnetic resonance tomography. It helps to distinguish between senile dementia of Alzheimer type and multi-infarct dementia. The enlargement of the ventricular system and cortical sulci is well established in schizophrenic and affective psychosis. Some alcohol addicts show a considerable degree of cerebral atrophy, only exceeded by demented patients, but this condition is potentially reversible. To screen psychiatric patients by CT is recommendable, as 2-10% of hospitalized psychiatric patients have structural brain disease. (orig.)

  20. Single-photon emission computed tomography and early death in acute ischemic stroke

    NARCIS (Netherlands)

    Limburg, M.; van Royen, E. A.; Hijdra, A.; de Bruïne, J. F.; Verbeeten, B. W.

    1990-01-01

    Single-photon emission computed tomography with thallium-201-labeled diethyldithiocarbamate was performed in 26 consecutive patients less than or equal to 24 hours after a supratentorial brain infarction. Computed tomography excluded other relevant pathology. Two observers assessed the initial

  1. X-ray computed tomography of PEM fuel cells

    Energy Technology Data Exchange (ETDEWEB)

    Pfrang, Andreas; Veyret, Damien; Tsotridis, Georgios [Commission of the European Communities, Petten (Netherlands). Joint Reseach Centre, Inst. for Energy; Janssen, Gaby [Energy Research Centre of the Netherlands ECN, Petten (Netherlands). Dept. of Hydrogen and Clean Fossil Fuels

    2010-07-01

    Proton exchange membrane (PEM) fuel cells were investigated by 3D x-ray computed tomography at a voxel size of 0.7 {mu}m. It is shown that this lab-based technique is not only suitable for the investigation of gas diffusion layers (GDL) as well as the investigation of membrane electrode assemblies (MEA), but also allows the calculation of macroscopic physical properties. The resolution of computed tomography is clearly sufficient to image the carbon fiber structure of gas diffusion layers in the as received GDLs as well as GDLs integrated into membrane electrode assemblies. It is also possible to visualize the catalyst layer within the MEA, which allows the investigation of layer thickness and structural defects on a larger scale than with conventional techniques. The macroscopic effective thermal conductivities of the gas diffusion layers were computed based on the 3D GDL structure reconstructed from tomography data to produce more reliable input data for fuel cell modeling. The computation was carried out by solving the energy equation considering a pure thermal conduction problem. The computations show - in agreement with the expectation and experimental data - that the through-plane thermal conductivities are lower than the in-plane thermal conductivities. (orig.)

  2. Fluorodeoxyglucose positron emission tomography-computed tomography findings in a case of xanthogranulomatous pyelonephritis

    Science.gov (United States)

    Joshi, Prathamesh; Lele, Vikram; Shah, Hardik

    2013-01-01

    Xanthogranulomatous pyelonephritis (XGNP) is an uncommon condition characterized by chronic suppurative renal inflammation that leads to progressive parenchymal destruction. This condition can clinically present as recurrent urinary tract infections, flank pain, hematuria, and occasionally sepsis, and weight loss. This condition is usually associated with obstructing renal calculus. We present 18-fluorodeoxyglucose positron emission tomography-computed tomography (18-FDG PET/CT) findings in an elderly male suffering from pyrexia and weight loss and suspected urinary tract infection. PET/CT findings in this case lead to diagnosis of XGNP. This diagnosis should be kept in mind while evaluating similar symptoms and PET/CT scan findings. PMID:24019680

  3. Changes seen on computed tomography of the chest in mildly symptomatic adult patients with sickle cell disease

    Energy Technology Data Exchange (ETDEWEB)

    Alves, Ursula David; Lopes, Agnaldo Jose; Maioli, Maria Christina Paixao; Soares, Andrea Ribeiro; Melo, Pedro Lopes de; Mogami, Roberto, E-mail: agnaldolopes.uerj@gmail.com [Universidade do Estado do Rio de Janeiro (UERJ), Rio de Janeiro, RJ (Brazil)

    2016-07-15

    Objective: To describe and quantify the main changes seen on computed tomography of the chest in mildly symptomatic adult patients with sickle cell disease, as well as to evaluate the radiologist accuracy in determining the type of haemoglobinopathy. Materials and Methods: A prospective study involving 44 adult patients with sickle cell disease who underwent inspiration and expiration computed tomography of the chest. The frequency of tomography findings and the extent of involvement are reported. We also calculated radiologist accuracy in determining the type of haemoglobinopathy by analyzing the pulmonary alterations and morphology of the spleen. Results: The changes found on computed tomography scans, in descending order of frequency, were as follows: fibrotic opacities (81.8%); mosaic attenuation (56.8%); architectural distortion (31.8%); cardiomegaly (25.0%); lobar volume reduction (18.2%); and increased caliber of peripheral pulmonary arteries (9.1%). For most of the findings, the involvement was considered mild, five or fewer lung segments being affected. The accuracy in determining the type of haemoglobinopathy (HbSS group versus not HbSS group) was 72.7%. Conclusion: In adult patients with sickle cell disease, the main tomography findings reflect fibrotic changes. In addition, computed tomography can be helpful in differentiating among haemoglobinopathies. (author)

  4. Changes seen on computed tomography of the chest in mildly symptomatic adult patients with sickle cell disease

    International Nuclear Information System (INIS)

    Alves, Ursula David; Lopes, Agnaldo Jose; Maioli, Maria Christina Paixao; Soares, Andrea Ribeiro; Melo, Pedro Lopes de; Mogami, Roberto

    2016-01-01

    Objective: To describe and quantify the main changes seen on computed tomography of the chest in mildly symptomatic adult patients with sickle cell disease, as well as to evaluate the radiologist accuracy in determining the type of haemoglobinopathy. Materials and Methods: A prospective study involving 44 adult patients with sickle cell disease who underwent inspiration and expiration computed tomography of the chest. The frequency of tomography findings and the extent of involvement are reported. We also calculated radiologist accuracy in determining the type of haemoglobinopathy by analyzing the pulmonary alterations and morphology of the spleen. Results: The changes found on computed tomography scans, in descending order of frequency, were as follows: fibrotic opacities (81.8%); mosaic attenuation (56.8%); architectural distortion (31.8%); cardiomegaly (25.0%); lobar volume reduction (18.2%); and increased caliber of peripheral pulmonary arteries (9.1%). For most of the findings, the involvement was considered mild, five or fewer lung segments being affected. The accuracy in determining the type of haemoglobinopathy (HbSS group versus not HbSS group) was 72.7%. Conclusion: In adult patients with sickle cell disease, the main tomography findings reflect fibrotic changes. In addition, computed tomography can be helpful in differentiating among haemoglobinopathies. (author)

  5. Computed tomography in congenital ocular motor apraxia

    Energy Technology Data Exchange (ETDEWEB)

    Eda, I.; Takashima, S.; Kitahara, T.; Ohno, K.; Takeshita, K.

    1984-09-01

    Unusual computed tomographic findings were observed in four patients with congenital ocular motor apraxia (COMA). These (CT) findings were characteristic in the posterior cranial fossa, with a dilated or deformed shape and size of the fourth ventricle, particularly its upper portion. One case revealed partial agenesis of the cerebellar vermis. It was suggested that the four patients subjected to CT showed abnormal topography of the cerebellar vermis or the brain stem. We postulate that these CT findings in COMA may have an important role in its pathogenesis.

  6. Computer-assisted irradiation planning by means of computed tomography

    International Nuclear Information System (INIS)

    Grauthoff, H.; Barwig, P.; Frommhold, H.

    1980-01-01

    Operation of the computer tomograph combined with a computer for irradiation planning leads to an optimization of radiotherapeutic efforts. By means of a careful carrying-over of computed tomographic data into the computing system the demanded homogeneous dose distribution with a deviation rate of +-10% may be accomplished to a large extent for any given target volume. At the same time this method achieves an optimal sparing of the sound or else critical organs. An evaluation unit independent of the diagnostics ought to be available, as this renders possible the adaption of the CT cross-sections of interest under individual aspects. (orig.) [de

  7. Low Accuracy of Computed Tomography and Positron Emission Tomography to Detect Lung and Lymph Node Metastases of Colorectal Cancer.

    Science.gov (United States)

    Guerrera, Francesco; Renaud, Stéphane; Schaeffer, Mickaël; Nigra, Victor; Solidoro, Paolo; Santelmo, Nicola; Filosso, Pier Luigi; Falcoz, Pierre-Emmanuel; Ruffini, Enrico; Oliaro, Alberto; Massard, Gilbert

    2017-10-01

    Minimally invasive surgery, stereotactic radiotherapy, and radiofrequency ablation are commonly proposed in the case of pulmonary colorectal-metastasis as alternatives to conventional open surgery. Preoperative imaging assessment by computed tomography (CT) scan and fluorodeoxyglucose positron emission tomography (FDG-PET) are critical to guide oncologic radical treatment. Our aim was to investigate the accuracy of CT and FDG-PET for the evaluation of the number of pulmonary colorectal metastases and thoracic lymph nodal involvement (LNI). Patients who underwent lung surgical resection for pulmonary colorectal metastases from 2004 to 2014 were analyzed. Concordance between histology, CT scan, and FDG-PET findings were assessed. Data of 521 patients were analyzed. Of those, FDG-PET was performed in 435 (83.5%). A moderate agreement between both CT scan (kappa index: 0.42) and FDG-PET (kappa index: 0.42) findings and the histologically proven number of metastases was observed. The number of histologically proven metastases was correctly discriminated in 61.7% of cases with CT scan and in 61.8% of cases with FDG-PET. Multiple metastases were discovered in 20.9% of clinical single metastasis cases with CT scan, and in 24.4% of those cases with FDG-PET. One hundred fifty patients (29.1%) presented with pathologic LNI. A poor agreement was observed between LNI and CT scan findings (kappa index: 0.02), and a weak agreement was observed concerning LNI and FDG-PET findings (kappa index: 0.39). Computed tomography and FDG-PET have limitations if the objective is to detect all malignant nodules and to discriminate the LNI in cases of pulmonary metastases of colorectal cancer. Copyright © 2017 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.

  8. Semi-quantitative myocardial perfusion measured by computed tomography in patients with refractory angina

    DEFF Research Database (Denmark)

    Qayyum, Abbas Ali; Kühl, Jørgen Tobias; Kjaer, Andreas

    2017-01-01

    INTRODUCTION: Computed tomography (CT) is a novel method for assessment of myocardial perfusion and has not yet been compared to rubidium-82 positron emission tomography (PET). We aimed to compare CT measured semi-quantitative myocardial perfusion with absolute quantified myocardial perfusion using...... scanner and CT/PET 64-slice scanner. CT measured myocardial attenuation density (AD) and perfusion index (PI) were correlated to absolute PET myocardial perfusion values. RESULTS: Rest AD, rest and stress PI did not correlate to PET findings (r = 0·412, P = 0·113; r = 0·300, P = 0·259; and r = 0·508, P...... PET and to detect stenotic territories in patients with severe coronary artery disease. MATERIALS AND METHODS: Eighteen patients with stenosis narrowing coronary arteries ≥70% demonstrated on invasive coronary angiography underwent rest and adenosine stress imaging obtained by 320-multidetector CT...

  9. Comparison of radiation absorbed dose in target organs in maxillofacial imaging with panoramic, conventional linear tomography, cone beam computed tomography and computed tomography

    Directory of Open Access Journals (Sweden)

    Panjnoush M.

    2009-12-01

    Full Text Available "nBackground and Aim: The objective of this study was to measure and compare the tissue absorbed dose in thyroid gland, salivary glands, eye and skin in maxillofacial imaging with panoramic, conventional linear tomography, cone beam computed tomography (CBCT and computed tomography (CT."nMaterials and Methods: Thermoluminescent dosimeters (TLD were implanted in 14 sites of RANDO phantom to measure average tissue absorbed dose in thyroid gland, parotid glands, submandibular glands, sublingual gland, lenses and buccal skin. The Promax (PLANMECA, Helsinki, Finland unit was selected for Panoramic, conventional linear tomography and cone beam computed tomography examinations and spiral Hispeed/Fxi (General Electric,USA was selected for CT examination. The average tissue absorbed doses were used for the calculation of the equivalent and effective doses in each organ."nResults: The average absorbed dose for Panoramic ranged from 0.038 mGY (Buccal skin to 0.308 mGY (submandibular gland, linear tomography ranged from 0.048 mGY (Lens to 0.510 mGY (submandibular gland,CBCT ranged from 0.322 mGY (thyroid glad to 1.144 mGY (Parotid gland and in CT ranged from 2.495 mGY (sublingual gland to 3.424 mGY (submandibular gland. Total effective dose in CBCT is 5 times greater than Panoramic and 4 times greater than linear tomography, and in CT, 30 and 22 times greater than Panoramic and linear tomography, respectively. Total effective dose in CT is 6 times greater than CBCT."nConclusion: For obtaining 3-dimensional (3D information in maxillofacial region, CBCT delivers the lower dose than CT, and should be preferred over a medical CT imaging. Furthermore, during maxillofacial imaging, salivary glands receive the highest dose of radiation.

  10. Computed tomography of the normal thymus

    International Nuclear Information System (INIS)

    Baron, R.L.; Lee, J.K.T.; Sagel, S.S.; Peterson, R.R.

    1982-01-01

    Recognition of variations in size, shape, and density of the normal thymus on computed tomographic (CT) scans is of paramount importance, less it be misinterpreted as an abnormal mediastinal mass. Studying patients subsequently proved free of active chest disease, we analyzed 154 CT scans of the mediastinum, performed on a fourth-generation scanner, to determine the incidence of visualization and appearance of the normal thymus. The thymus was seen in 100% of patients under age 30, 73% of patients between 30 and 49 years, and in 17% of patients over 49 years of age. The thickness of the thymus showed a definite decrease in size with increasing age; although the width showed a similar general tendency, a wide variation was noted within each age group. In younger patients, the density of the thymus was similar to that of muscle; the attenuation values progressively decreased in older patients, finally approaching that of fat

  11. Computer tomography: a cost-saving examination?

    International Nuclear Information System (INIS)

    Barneveld Binkhuysen, F.H.; Puijlaert, C.B.A.J.

    1987-01-01

    The research concerns the influence of the body computer tomograph (BCT) on the efficiency in radiology and in the hospital as a whole in The Netherlands. Hospitals with CT are compared with hospitals without CT. In radiology the substitution effect is investigated, with use of the number of radiological performances per clinical patient as a parameter. This parameter proves to decrease in hospitals with a CT, in contrast to hospitals without a CT. The often-expressed opinion that the CT should specifically perform complementary examinations appears incorrect. As to the efficiency in the hospital this is related to the average hospital in-patient stay. The average hospital in-patient stay proves to be shorter in hospitals with a CT than in those without a CT. The CT has turned out to be a very effective expedient which unfortunately, however, is being used inefficiently in The Netherlands, owing to limited installation. 17 refs.; 6 figs.; 5 tabs

  12. Computed tomography of the acetabular fractures

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Ho Young; Suh, Jin Suck; Park, Chang Yun; Lee, Kil Woo [Yonsei University College of Medicine, Seoul (Korea, Republic of)

    1986-04-15

    In a retrospective study of 21 patients, in whom the acetabular fractures were suspected on initial radiographs, we compared and analysed the computed tomographic findings and plain radiographic findings. The results were as follow: 1. In patients with multiple trauma, no further change in position was required during CT examinations. 2. CT showed intraarticular loose bodies, which were invisible on plain radiographs. 3. CT was useful in detecting the fractures of acetabular rims, medial wall of acetabulum, and femoral head. 4. CT permitted better evaluation of shape, extent, and degree of separation of fracture fragments. 5. CT was helpful in detecting the associated fractures and soft tissue injuries. 6. CT also demonstrated the adequacy of reduction, the position of metallic fixation devices, and the presence or absence of remaining intraarticular osseous fragments after surgery.

  13. Intracranial calcification on paediatric computed tomography

    International Nuclear Information System (INIS)

    Kendall, B.; Cavanagh, N.

    1986-01-01

    An analysis of the computed tomograms of 18000 children examined consecutively form the basis of an assessment of the diagnostic significance of intracranial calcification. The low incidence of physiological calcification in the pineal and choroid of about 2% up to the age of 8 years, but increasing 5-fold by the age of 15 years, is confirmed. Pathological calcification occurred in 1.6%, the commonest causes being neoplasms (43%), neuroectodermal syndromes (20%) and infections (12%). Diffuse basal ganglia calcification (15%) bore little relation to the diverse clinical symptomatology, and routine bio-chemical studies showed a disorder of metabolism to be present in only 6 cases. Calcification has not been previously noted in acute haemorrhagic leukoencephalitis, Pertussis or Cocksackie encephalitis, infantile neuraxonal dystrophy, Marinesco-Sjoegren syndrome or in the basal ganglia in neurofibromatosis. (orig.)

  14. Computed tomography for sequelae of brain contusions

    International Nuclear Information System (INIS)

    Aminov, M.

    1995-01-01

    Follow-up clinical and computed tomographic (CT) studies were performed in 140 patients with focal brain contusions at the acute stage of brain injury (BI). A total of 133 victims were followed up and the time course of CT changes were examined in the intervening and late BI periods. Despite the favourable natural history of acute BI, mild, moderate, and severe posttraumatic changes were shown to appear as cicatricial-adhesive and atrophic processes, intracerebral cysts, porencephalies, which result in posttraumatic epilepsy, hydrocephalus and others. The magnitude of diffuse changes rather than focal changes in the area of the prior medullary lesion was found to play the leading role in the victims disability [ru

  15. Tomography

    International Nuclear Information System (INIS)

    1985-01-01

    Already widely accepted in medicine, tomography can also be useful in industry. The theory behind tomography and a demonstration of the technique to inspect a motorcycle carburetor is presented. To demonstrate the potential of computer assisted tomography (CAT) to accurately locate 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

  16. Role of isotope scan, including positron emission tomography/computed tomography, in nodular goitre.

    Science.gov (United States)

    Giovanella, Luca; Ceriani, Luca; Treglia, Giorgio

    2014-08-01

    Nuclear medicine techniques were first used in clinical practice for diagnosing and treating thyroid diseases in the 1950s, and are still an integral part of thyroid nodules work-up. Thyroid imaging with iodine or iodine-analogue isotopes is the only examination able to prove the presence of autonomously functioning thyroid tissue, which excludes malignancy with a high probability. In addition, a thyroid scan with technetium-99m-methoxyisobutylisonitrile is able to avoid unnecessary surgical procedures for cytologically inconclusive thyroid nodules, as confirmed by meta-analysis and cost-effectiveness studies. Finally, positron emission tomography alone, and positron emission tomography combined with computed tomography scans with (18)F-fluoro-2-deoxy-d-glucose are also promising for diagnosing thyroid diseases, but further studies are needed before introducing them to clinical practice. Copyright © 2014 Elsevier Ltd. All rights reserved.

  17. Computed tomography of human joints and radioactive waste drums

    International Nuclear Information System (INIS)

    Martz, Harry E.; Roberson, G. Patrick; Hollerbach, Karin; Logan, Clinton M.; Ashby, Elaine; Bernardi, Richard

    1999-01-01

    X- and gamma-ray imaging techniques in nondestructive evaluation (NDE) and assay (NDA) have seen increasing use in an array of industrial, environmental, military, and medical applications. Much of this growth in recent years is attributed to the rapid development of computed tomography (CT) and the use of NDE throughout the life-cycle of a product. Two diverse examples of CT are discussed, 1.) Our computational approach to normal joint kinematics and prosthetic joint analysis offers an opportunity to evaluate and improve prosthetic human joint replacements before they are manufactured or surgically implanted. Computed tomography data from scanned joints are segmented, resulting in the identification of bone and other tissues of interest, with emphasis on the articular surfaces. 2.) We are developing NDE and NDA techniques to analyze closed waste drums accurately and quantitatively. Active and passive computed tomography (A and PCT) is a comprehensive and accurate gamma-ray NDA method that can identify all detectable radioisotopes present in a container and measure their radioactivity

  18. Initial water quantification results using neutron computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Heller, A.K. [Department of Mechanical and Nuclear Engineering, Pennsylvania State University (United States)], E-mail: axh174@psu.edu; Shi, L.; Brenizer, J.S.; Mench, M.M. [Department of Mechanical and Nuclear Engineering, Pennsylvania State University (United States)

    2009-06-21

    Neutron computed tomography is an important imaging tool in the field of non-destructive testing and in fundamental research for many engineering applications. Contrary to X-rays, neutrons can be attenuated by some light materials, such as hydrogen, but can penetrate many heavy materials. Thus, neutron computed tomography is useful in obtaining important three-dimensional information about a sample's interior structure and material properties that other traditional methods cannot provide. The neutron computed tomography system at Pennsylvania State University's Radiation Science and Engineering Center is being utilized to develop a water quantification technique for investigation of water distribution in fuel cells under normal conditions. A hollow aluminum cylinder test sample filled with a known volume of water was constructed for purposes of testing the quantification technique. Transmission images of the test sample at different angles were easily acquired through the synthesis of a dedicated image acquisition computer driving a rotary table controller and an in-house developed synchronization software package. After data acquisition, Octopus (version 8.2) and VGStudio Max (version 1.2) were used to perform cross-sectional and three-dimensional reconstructions of the sample, respectively. The initial reconstructions and water quantification results are presented.

  19. Computed tomography of human joints and radioactive waste drums

    Science.gov (United States)

    Martz, Harry E.; Roberson, G. Patrick; Hollerbach, Karin; Logan, Clinton M.; Ashby, Elaine; Bernardi, Richard

    1999-12-01

    X- and gamma-ray imaging techniques in nondestructive evaluation (NDE) and assay (NDA) have seen increasing use in an array of industrial, environmental, military, and medical applications. Much of this growth in recent years is attributed to the rapid development of computed tomography (CT) and the use of NDE throughout the life-cycle of a product. Two diverse examples of CT are discussed, 1.) Our computational approach to normal joint kinematics and prosthetic joint analysis offers an opportunity to evaluate and improve prosthetic human joint replacements before they are manufactured or surgically implanted. Computed tomography data from scanned joints are segmented, resulting in the identification of bone and other tissues of interest, with emphasis on the articular surfaces. 2.) We are developing NDE and NDA techniques to analyze closed waste drums accurately and quantitatively. Active and passive computed tomography (A&PCT) is a comprehensive and accurate gamma-ray NDA method that can identify all detectable radioisotopes present in a container and measure their radioactivity.

  20. Fluorodeoxyglucose-positron emission tomography/computed tomography imaging features of colloid adenocarcinoma of the lung: a case report.

    Science.gov (United States)

    Wang, ZhenGuang; Yu, MingMing; Chen, YueHua; Kong, Yan

    2017-07-27

    Colloid adenocarcinoma of the lung is a rare subtype of variants of invasive adenocarcinomas. We report the appearance of this unusual entity on 18 F-fluorodeoxyglucose positron emission tomography/computed tomography. A 60-year-old man of Chinese Han nationality coughed with a little white sputum for 1 month. Chest computed tomography showed multiple bilateral subpleural nodules and plaques accompanied by air bronchograms, which were most concentrated in the lower lobe of his right lung. Positron emission tomography indicated increased radioactivity uptake with a maximum standardized uptake value of 3.5. Positron emission tomography/computed tomography showed a soft tissue density lesion in his left adrenal gland with a maximum standardized uptake value of 4.1. The positron emission tomography/computed tomography appearance suggested a primary colloid adenocarcinoma in the lower lobe of his right lung accompanied by intrapulmonary and left adrenal gland metastases. The diagnostic rate of colloid adenocarcinoma can be increased by combining the anatomic and metabolic information of lesions. The advantage of positron emission tomography/computed tomography in the diagnosis of colloid adenocarcinoma, as with other cancers, is the ability to locate extrapulmonary disease, facilitating clinical staging.

  1. Brain computed tomography of the hypertensive patients

    International Nuclear Information System (INIS)

    Bae, W. K.; Park, C. K.; Cho, O. K.; Hahm, C. K.

    1980-01-01

    Now a day, hypertension is more increasing in frequency and ranked the top of the causes of death in Korea and other nations. Most of cerebrovascular accidents in hypertensive patients are composed of vascular occlusive changes and hemorrhages. In cerebral angiogram, we can only detect occlusion of large artery and large mass effect from hematoma or cerebral infarction without identification of its entity. The computed tomogram, however, is the best way for evaluation of cerebrovascular diseases including detection of nature, location, amount, and associated changes. This study includes evaluation of computed tomograms of 106 patients with hypertension during the period of 17 months from Feb. 1979 to June 1980 in the department of radiology, college of Medicine, Hanyang University. The results were as follows. 1. Age distribution of the total 106 patients was broad ranging from 25 years to 76 years. 67.9% of patients were over the age of 50. The male and female sex ratio was 3:2. 2. 28 out of 106 patients were normal and 78 patients revealed abnormal on C. T. findings; those were intracranial hemorrhage (35 patients), cerebral infarction (32 patients) and brain atrophy (11 patients). 3. All of the intracranial hemorrhage except one were intracerebral hemorrhage; those were located in the cerebral hemisphere (19 patients), basal ganglia (15 patients) and brain stem (1 patient). The except one case of intracranial hemorrhage was subdural hematoma. 7 patients of intraventricular hemorrhage and 1 patient of subarachnoid hemorrhage were combined with intracerebral hemorrhage. 2/3 of patients who had hemorrhage in cerebral hemisphere revealed lesions in the parietal and temporal lobes. 4. In cases of cerebral infarction, the cerebral hemisphere was most common site of lesion (20 cases), and the next was basal ganglia (11 cases). Most of the infarcts in cerebral hemisphere were located in the parietal and temporal lobes. The left basal ganglia was more commonly involved

  2. The usefulness of computed tomography in the diagnosis and evaluation of surgical indication of acute appendicitis

    International Nuclear Information System (INIS)

    Kondo, Hiroshi; Shimizu, Ryoichi; Ozasa, Hiroaki; Eto, Ryuichi

    2009-01-01

    We evaluated the usefulness of computed tomography (CT) in diagnosing and management acute appendicitis. We studied 133 patients diagnosed with acute appendicitis confirmed by plain CT between March 2004 and November 2008. Sixty-nine of these patients underwent appendectomy, 64 were treated conservatively. Recurrence of acute appendicitis was recognized in 13 out of 64 patients treated conservatively, and appendectomy was done in 8. On the CT findings of 77 patients who underwent appendectomy, appendicoliths were shown in 50 patients. In 64 patients treated conservatively, 14 patients had images of calcified appendicoliths. Eight out of 14 patients with appendicoliths had small calcifications, which were not obstructive in inner lumen of appendix. Inflammatory signs (increased white blood cell (WBC) and C reactive protein (CRP), and fever) with positive signs on CT, including calcifications, periappendicular infiltration, free fluid etc., are useful in confirming the clinical diagnosis and directing treatment (operative versus conservative) of patient. (author)

  3. Role of computed tomography in pancreatic trauma

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Sun Hee; Kim, Ki Whang; Lee, Jong Tae; Oh, Sei Jung [College of Medicine, Yonsei University, Seoul (Korea, Republic of)

    1991-03-15

    At Yonsei University Hospital from January 1984 to August 1990, computed tomographic (CT) scans of 13 patients with surgically proven pancreatic injuries after blunt abdominal trauma, including 6 pancreatic lacerations or contusions, 6 pancreatic fractures, and one post-traumatic pseudocyst, were retrospectively reviewed to determine the role and accuracy of the CT in evaluating pancreatic injury. CT can document gross pancreatic injury by showing focal or diffuse enlargement (1), area of diminished attenuation (3), separation (5), focal hematoma (2), and peripancreatic change, including peripancreatic hematoma (2), fluid collection (11), perirenal fascial thickening (10), omental and mesenteric change (5), and bowel change (2). CT correctly diagnosed pancreatic fracture in 5 cases, post-raumatic pseudocyst in 1 case, and pancreatic laceration in 3 cases in 9 of these patients. There were 4 false negative diagnoses, including 3 pancreatic lacerations and 1 pancreatic fracture. A CT is of pancreatic trauma could be difficult to diagnosis in patients who are scanned within 24 hrs after an injury or to distinguish a motion or streak artifact caused by a nasogastric tube or air-oral contrast fluid level in the stomach.

  4. Ring enhancement in contrast enhancement computed tomography

    International Nuclear Information System (INIS)

    Inatsuki, Shinichi; Hayashi, Kuniaki; Miyake, Hidetoshi

    1979-01-01

    Ring enhancement was examined in 11 lesions, 61 patients, we experienced. The frequency of ring enhancement observed in cerebral abscesses and tumors and the characteristics and the differential points of each disease were obtained. The frequency of ring enhancement was 54% in metastatic cerebral tumor, 56% in glioblastoma and astrocytoma (grade III) and 100% in cerebral abscess. Glioblastoma and astrocytoma (grade III) differed from other diseases in having distorted rings with poor uniform thickness. Although there was a great similarity between the computed tomographic picture of metastatic cerebral tumor and that of cerebral abscess, the ring in cerebral abscess was clearer, thin and uniform, and the peripheral edema in cerebral abscess was weak in general. In cerebral infarct, peripheral edema and mass effect of the ring were not observed or slightly observed, if any. Considering only the characteristics of the rings, there are differences between each diseases, and differentiation seems to be possibly performed. In practice, however, it is not necessarily easy to make a differential diagnosis. Clinical results should be carefully managed. (Kumagai, M.)

  5. Computed tomography of the cervical compartments on the computer tomogram

    Energy Technology Data Exchange (ETDEWEB)

    Zaunbauer, W.; Haertel, M.

    1984-02-01

    The computed tomographic anatomy of the cervical compartments, with emphasis on the fascial planes of the neck, is described. Typical disease processes within these fascial confined compartments have been documented.

  6. Drowning investigated by post mortem computed tomography and autopsy

    DEFF Research Database (Denmark)

    Leth, Peter Mygind; Madsen, Betina Hauge

    2017-01-01

    Case control study of drowning fatalities investigated with autopsy and post mortem computed tomography (PMCT). 40 drowning fatalities (25 men, 15 women; 24 salt water, 16 fresh water) and 80 controls were included. The aim was to investigate the difference in lung tissue density (g/liter) and ra......Case control study of drowning fatalities investigated with autopsy and post mortem computed tomography (PMCT). 40 drowning fatalities (25 men, 15 women; 24 salt water, 16 fresh water) and 80 controls were included. The aim was to investigate the difference in lung tissue density (g...... individual or when comparing drowned individuals with controls. The lung density was measured by a combination of PMCT measured total lung volume and autopsy measured total lung weight. We found that the lung density and the lung radio density were decreased, the lung volume increased and the lung weights...

  7. Computed tomography of the adrenals in patients with tuberculosis

    International Nuclear Information System (INIS)

    Yamashita, Seizo; Machado, Jussara Marcondes; Morceli, Jose

    2004-01-01

    We evaluated the adrenals of individuals without tuberculosis (group 1 - G1) and with tuberculosis (group 2 - G2) using computed tomography. The antero-posterior length, the thickness, and the longitudinal length of the adrenals were compared in G1 and G2. The duration of the disease, the occurrence of morphologic abnormalities in G2, the distribution according to sex, age and skin color were also studied. There was difference in the antero-posterior length and thickness of right adrenal between G1 and G2. A higher prevalence of white skin male individuals was observed in G2. There was no association between duration of the disease and the occurrence of morphologic abnormalities in G2. A higher occurrence of adrenal enlargement was observed in G2. The main computed tomography findings in patients with tuberculosis were enlargement of the adrenal without calcification, enlargement of the adrenal with punctiform calcifications, and residual calcification of the adrenal. (author)

  8. Cranial computed tomography in maple syrup urine disease

    International Nuclear Information System (INIS)

    Irnberger, T.; Ploechl, E.; Rittinger, O.; Bachmann, C.; Pilz, P.; Walter, G.F.; Wendel, U.; Landeskrankenanstalten Salzburg; Bern Univ.; Landesnervenklinik Salzburg; Graz Univ.; Dudley Observatory, Albany, NY; Duesseldorf Univ.

    1986-01-01

    Cranial computed tomography in the initial stage of the intermediate phenotype of maple syrup urine disease (MSUD) demonstrates diffuse, symmetric hypodensities in white and grey matter, which show a complete return to normal after early introduction of an adequate protein-restrictive diet. If diagnosis of this disease is missed or delayed, progressive global (end-stage) atrophy will take place over several years. A decrease in density values correlates well with the total cerebral lipid and water content (closely related to myelinisation), whereas progression and grade of atrophy show a relationship with the severity of pathological white and grey matter changes that are not demonstrable with computed tomography but can be proven histologically. Analysis of both morphological parameters corresponds well with clinical-neurological outcome and therapeutic success. (orig.) [de

  9. Survey of computed tomography doses in head and chest protocols

    International Nuclear Information System (INIS)

    Souza, Giordana Salvi de; Silva, Ana Maria Marques da

    2016-01-01

    Computed tomography is a clinical tool for the diagnosis of patients. However, the patient is subjected to a complex dose distribution. The aim of this study was to survey dose indicators in head and chest protocols CT scans, in terms of Dose-Length Product(DLP) and effective dose for adult and pediatric patients, comparing them with diagnostic reference levels in the literature. Patients were divided into age groups and the following image acquisition parameters were collected: age, kV, mAs, Volumetric Computed Tomography Dose Index (CTDIvol) and DLP. The effective dose was found multiplying DLP by correction factors. The results were obtained from the third quartile and showed the importance of determining kV and mAs values for each patient depending on the studied region, age and thickness. (author)

  10. Performance of an extrapolation chamber in computed tomography standard beams

    Energy Technology Data Exchange (ETDEWEB)

    Castro, Maysa C.; Silva, Natália F.; Caldas, Linda V.E., E-mail: mcastro@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2017-07-01

    Among the medical uses of ionizing radiations, the computed tomography (CT) diagnostic exams are responsible for the highest dose values to the patients. The dosimetry procedure in CT scanner beams makes use of pencil ionization chambers with sensitive volume lengths of 10 cm. The aim of its calibration is to compare the values that are obtained with the instrument to be calibrated and a standard reference system. However, there is no primary standard system for this kind of radiation beam. Therefore, an extrapolation ionization chamber built at the Calibration Laboratory (LCI), was used to establish a CT primary standard. The objective of this work was to perform some characterization tests (short- and medium-term stabilities, saturation curve, polarity effect and ion collection efficiency) in the standard X-rays beams established for computed tomography at the LCI. (author)

  11. A novel dosimetry system for computed tomography using phototransistor

    International Nuclear Information System (INIS)

    Magalhães, C.M.S.; Sobrinho, M.L.; Souza, D.N.; Filho, J. Antônio; Silva, E.F. da; Santos, L.A.P.

    2012-01-01

    Computed tomography (CT) dosimetry normally uses an ionization chamber 100 mm long to estimate the computed tomography dose index (CTDI), however some reports have already indicated that small devices could replace the long ion chamber to improve quality assurance procedures in CT dosimetry. This paper presents a novel dosimetry system based in a commercial phototransistor evaluated for CT dosimetry. Three detector configurations were developed for this system: with a single, two and four devices. Dose profile measurements were obtained with them and their angular responses were evaluated. The results showed that the novel dosimetry system with the phototransistor could be an alternative for CT dosimetry. It allows to obtain the CT dose profile in details and also to estimate the CTDI in longer length than the 100 mm pencil chamber. The angular response showed that the one device detector configuration is the most adequate among the three configurations analyzed in this study.

  12. Computed tomography with multidetectors in the diagnosis of coronary stenosis

    International Nuclear Information System (INIS)

    Lombo, Bernardo; Carvajal, Codos A; Tafur, Monica; Gomez, Rafael

    2007-01-01

    Coronary angiography that uses multislice spiral computed tomography is a noninvasive technique for the detection of coronary stenosis that has had significant improvements in recent years. The introduction of 16 and 64 row scanners, the development of synchronized scanning electrocardiogram and better reconstruction techniques permit higher spatial and temporal resolution that allows better identification of coronary plaques and significant obstructive coronary lesions. In the next years Multislice spiral computed tomography will continue maturing and it will become a useful non invasive diagnostic imaging tool for the diagnosis of coronary disease and will be integrated to the cardiologic management protocols. Our next review will be focused on the basic and technical aspects of the scanner, diagnostic performance and clinical applications of this new technology

  13. Thorax computed tomography findings in patients victims of chest trauma

    Directory of Open Access Journals (Sweden)

    Francisco Jose Rodrigues de Moura Filho

    2015-12-01

    Full Text Available Objective: To describe thorax computed tomography findings in patients assisted in the emergency unit of Institute Dr Jose Frota (IJF. Materials and Methods: Descriptive study analyzing 160 consecutive contrast-enhanced thorax computed tomography of patients victims of thoracic trauma admitted to the emergency unit of IJF, between November 1st, 2014 and January 31st, 2015. Results: Abnormal findings were observed in 91,2 % of the patients. Among them, the following findings were most frequently observed: fractures (48%, hemothorax (43%, atelectasis (37%, pneumothorax (26% and lung contusions (17% Rupture of the esophagus was seen in three patients. Conclusion: We recognize that the findings encountered in our study are of similar prevalence to the ones reported in the literature and that CT scan is essencial to quickly diagnose these findings.

  14. Radiation exposure of infants and children in computed tomography

    International Nuclear Information System (INIS)

    Schmidt, T.; Stieve, F.E.

    1980-01-01

    The radiation exposure of infants and small children with Computed Tomography is different in several aspects from that of adults undergoing an identical examination. The surface dose at radiation entrance is higher in children because of a smaller body diameter for the same dose rate at the tube. The critical organ dose in the directly irradiated area is higher in children than in adults. The exposure of organs outside the examined area is also higher in children -because of short intervals- than in adults. The absorbed energy, i.e. integral dose, however, is lower in children than in adults because of the lesser volume. The differences between conventional procedures and Computed Tomography, are greater in children than in adults. Here, CT shows higher values than conventional explorations. As a result of the low number of examinations with CT, the contribution towards a genetically significant dose is currently, at least, relatively small [fr

  15. Technical competence in cardiovascular magnetic resonance and computed tomography

    International Nuclear Information System (INIS)

    Fernandes, Juliano Lara; Shiozaki, Afonso Akio; Azevedo Filho, Clerio Francisco de; Rochitte, Carlos Eduardo; Pinto, Ibraim Marciarelli Francisco; Lopes, Marly Maria Uellendahl; Schvartzman, Paulo Roberto

    2009-01-01

    Cardiovascular magnetic resonance and computed tomography have evolved as very practical and useful techniques applied in clinical cardiology. Due to their rapid acceptance in the cardiology community and widespread use, training of both cardiologists and radiologists on this subspecialty has not been homogeneous so far. This in part explains significant differences observed in the diverse background found in today’s practicing physicians who execute these exams. In order to guide training facilities as well as both payers, contractors and general cardiologists ordering the exam, this document provides a minimum standard that should be accomplished by all physicians who pursue education in the field and for those who already practice in it. The clinical competences listed in this statement are by no means thorough but should be required by all those involved in cardiovascular magnetic resonance and computed tomography as the customary requirements for current and future practitioners. (author)

  16. Mandibular condyle position in cone beam computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Hwang, Hyoung Joo; Kim, Gyu Tae; Choi, Yong Suk; Hwang, Eui Hwan [Kyung Hee Univ. School of Dentistry, Seoul (Korea, Republic of)

    2006-06-15

    To evaluate position of the mandibular condyle within articular fossa in an asymptomatic population radiographically by a cone beam computed tomography. Cone beam computed tomography of 60 temporomandibular joints was performed on 15 males and 15 females with no history of any temporomandibular disorders, or any other orthodontic or photoconductors treatments. Position of mandibular condyle within articular fossa at centric occlusion was evaluated. A statistical evaluation was done using a SPSS. In the sagittal views, mandibular condyle within articular fossa was laterally located at central section. Mandibular condyles in the right and left sides were showed asymmetric positional relationship at medial, central, and lateral sections. Mandibular condyle within articular fossa in an asymptomatic population was observed non-concentric position in the sagittal and coronal views.

  17. Mandibular condyle position in cone beam computed tomography

    International Nuclear Information System (INIS)

    Hwang, Hyoung Joo; Kim, Gyu Tae; Choi, Yong Suk; Hwang, Eui Hwan

    2006-01-01

    To evaluate position of the mandibular condyle within articular fossa in an asymptomatic population radiographically by a cone beam computed tomography. Cone beam computed tomography of 60 temporomandibular joints was performed on 15 males and 15 females with no history of any temporomandibular disorders, or any other orthodontic or photoconductors treatments. Position of mandibular condyle within articular fossa at centric occlusion was evaluated. A statistical evaluation was done using a SPSS. In the sagittal views, mandibular condyle within articular fossa was laterally located at central section. Mandibular condyles in the right and left sides were showed asymmetric positional relationship at medial, central, and lateral sections. Mandibular condyle within articular fossa in an asymptomatic population was observed non-concentric position in the sagittal and coronal views

  18. Os Trigonum – Sheer Incidental or Quite Significant? Single Photon Emission Computed Tomography/Computed Tomography's Role in a Case of Ankle Impingement

    International Nuclear Information System (INIS)

    Chokkappan, Kabilan; Srinivasan, Sivasubramanian; Subramanian, Manickam; Kannivelu, Anbalagan

    2015-01-01

    Accessory ossicles are widely prevalent in the ankle and foot. Although they are often asymptomatic, they can present clinically with symptoms at times. When they occur bilaterally in a patient who presents with unilateral complaints, it is clinically difficult to attribute the symptoms to the presence of these common anatomic variants. One needs specific imaging to assess the clinical relevance of the accessory ossicles, in order to tailor the treatment plan. The case presented in this article is one such example, where the patient presented with chronic unilateral ankle pain and initial radiographs revealed bilateral os trigonum and os subtibiale. He underwent a technetium-99m methyl diphosphonate (Tc-99m MDP) bone scan and single photon emission computed tomography/computed tomography (SPECT/CT). The Tc-99m MDP scan showed a focal uptake in the ankle of concern. SPECT/CT complemented the finding by exactly localizing the uptake to the posterior subtalar joint and around the os trigonum, thereby pointing to the diagnosis of os trigonum syndrome

  19. A computed tomography-based spatial normalization for the analysis of [18F] fluorodeoxyglucose positron emission tomography of the brain.

    Science.gov (United States)

    Cho, Hanna; Kim, Jin Su; Choi, Jae Yong; Ryu, Young Hoon; Lyoo, Chul Hyoung

    2014-01-01

    We developed a new computed tomography (CT)-based spatial normalization method and CT template to demonstrate its usefulness in spatial normalization of positron emission tomography (PET) images with [(18)F] fluorodeoxyglucose (FDG) PET studies in healthy controls. Seventy healthy controls underwent brain CT scan (120 KeV, 180 mAs, and 3 mm of thickness) and [(18)F] FDG PET scans using a PET/CT scanner. T1-weighted magnetic resonance (MR) images were acquired for all subjects. By averaging skull-stripped and spatially-normalized MR and CT images, we created skull-stripped MR and CT templates for spatial normalization. The skull-stripped MR and CT images were spatially normalized to each structural template. PET images were spatially normalized by applying spatial transformation parameters to normalize skull-stripped MR and CT images. A conventional perfusion PET template was used for PET-based spatial normalization. Regional standardized uptake values (SUV) measured by overlaying the template volume of interest (VOI) were compared to those measured with FreeSurfer-generated VOI (FSVOI). All three spatial normalization methods underestimated regional SUV values by 0.3-20% compared to those measured with FSVOI. The CT-based method showed slightly greater underestimation bias. Regional SUV values derived from all three spatial normalization methods were correlated significantly (p brain regions or highly variable within study population.

  20. Corrected coronary opacification decrease from coronary computed tomography angiography: Validation with quantitative 13N-ammonia positron emission tomography.

    Science.gov (United States)

    Benz, Dominik C; Gräni, Christoph; Ferro, Paola; Neumeier, Luis; Messerli, Michael; Possner, Mathias; Clerc, Olivier F; Gebhard, Catherine; Gaemperli, Oliver; Pazhenkottil, Aju P; Kaufmann, Philipp A; Buechel, Ronny R

    2017-07-06

    To assess the functional relevance of a coronary artery stenosis, corrected coronary opacification (CCO) decrease derived from coronary computed tomography angiography (CCTA) has been proposed. The present study aims at validating CCO decrease with quantitative 13N-ammonia positron emission tomography (PET) myocardial perfusion imaging (MPI). This retrospective study consists of 39 patients who underwent hybrid CCTA/PET-MPI. From CCTA, attenuation in the coronary lumen was measured before and after a stenosis and corrected to the aorta to calculate CCO and its decrease. Relative flow reserve (RFR) was calculated by dividing the stress myocardial blood flow (MBF) of a vessel territory subtended by a stenotic coronary by the stress MBF of the reference territories without stenoses. RFR was abnormal in 11 vessel territories (27%). CCO decrease yielded a sensitivity, specificity, negative predictive value, positive predictive value, and accuracy for prediction of an abnormal RFR of 73%, 70%, 88%, 47%, and 70%, respectively. CCTA-derived CCO decrease has moderate diagnostic accuracy to predict an abnormal RFR in PET-MPI. However, its high negative predictive value to rule out functional relevance of a given lesion may confer clinical implications in the diagnostic work-up of patients with a coronary stenosis.

  1. Clinico-radiological correlation of Wilson's disease by magnetic resonance imaging, computed tomography and positron emission tomography

    Energy Technology Data Exchange (ETDEWEB)

    Ikeda, Ken; Sakata, Chigusa; Nemoto, Hiroshi; Yokoi, Fuji; Sunohara, Nobuhiko (National Center of Neurology and Psychiatry, Kodaira, Tokyo (Japan)); Iio, Masaaki

    1991-02-01

    Five patients with Wilson's disease received repeated magnetic resonance imaging (MRI) and computed tomography (CT) examinations at intervals from 6 to 29 months. Four patients, except for asymptomatic one, also underwent positron emission tomography (PET). The significance and limitations of these imaging modalities were examined in the light of their correlation with clinical manifestations and their therapeutic evaluation. The following focal regions, detected on MRI, had a strong positive correlation with clinical manifestations: the lenticular nuclei for dystonia, the brain stem for abnormality of smooth persuit eye movements, and the caudate and lenticular nuclei for severe dysarthria/dysphagia. Follow-up MRI for 3 patients showed an improvement of findings in the lenticular nuclei, lateral part of the putamen, and brain stem, that was in accordance with improved clinical or neurologic manifestations, such as dystonia and cerebellar symptoms. Severe abnormality in the caudate nucleus was associated with poor prognosis. Repeated CT failed to show serial changes in any of the patients. Regional blood flow and oxygen metabolic rate, obtained by PET examinations, were slightly decreased in the thalamus that had normal findings on both MRI and CT, as well as in the cerebral cortex and basal ganglia. PET was, however, inferior to MRI in detecting fine foci within the basal ganglia. In conclusion, there was a good correlation between MRI findings, particularly foci of the caudate and lenticular nuclei, and clinical manifestations. Repeated MRI examinations were the most useful approach to the evaluation of therapeutic effects and prognosis. (N.K.).

  2. A Clinical Evaluation of Cone Beam Computed Tomography

    Science.gov (United States)

    2015-06-01

    morphology based on conventional imaging • Identification of root canal system anomalies and determination of root curvature • Diagnosis of dental ...A CLINICAL EVALUATION OF CONE BEAM COMPUTED TOMOGRAPHY by Thomas Patrick Cairnll, D.D.S. Commander, Dental Corps United States Navy A thesis...submitted to the Faculty of the Endodontics Graduate Program Naval Postgraduate Dental School Uniformed Services University of the Health Sciences in

  3. The role of computed tomography in modern paediatric uroradiology

    Energy Technology Data Exchange (ETDEWEB)

    Maudgil, D.D.; McHugh, K. E-mail: kmchugh@gosh.nhs.uk

    2002-08-01

    Computed tomography (CT) has developed a well-recognised role within paediatric uroradiology, especially in imaging of trauma, malignancy (in particular Wilms' tumour), atypical infection, and congenital urogenital abnormalities. CT can also be used for problem solving in nephrolithiasis and renal transplant assessment. These applications are illustrated and discussed, with an emphasis on particular information that can be gained from the CT study.

  4. Computed tomography angiography in the investigation of carotid stenosis

    Energy Technology Data Exchange (ETDEWEB)

    Goddard, A.J.P.; Mendelow, A.D.; Birchall, D

    2001-07-01

    The assessment of carotid atherosclerotic disease is an essential pre-requisite for determining a patients suitability for carotid endarterectomy to prevent ischaemic stroke. Catheter angiography is regarded as the most accurate investigative tool for this purpose. However, with its finite morbidity and invasiveness, there is an increasing reliance upon non-invasive methods to accurately assess carotid disease. We present a review of the technique and applications of computed tomography angiography. Goddard, A.J. P.et al. (2001)

  5. Computed tomography in complex fractures of the ankle joint

    Energy Technology Data Exchange (ETDEWEB)

    Friedburg, H.; Wimmer, B.; Hendrich, V.; Riede, U.N.

    1983-09-01

    Diagnostic value of conventional roentgen technique and computed tomography is proofed by examination of 50 patients with sprain fractures of the ankle joint. The dimension of destruction of the distal tibial joint surface is better documented by CT than by other radiological techniques. Additional informations like multiframentation of the distal tibia or evaluation of reposition impediment are found more frequently by CT. Therefore indication and planning of the traumatherapy can be assessed better by the traumatologist.

  6. Computed tomography in patients with Ehlers-Danlos syndrome

    Energy Technology Data Exchange (ETDEWEB)

    Hagino, Hiroshi; Sugitani, Akitoshi; Eda, Isematsu; Takashima, Sachio; Takeshita, Kenzo

    1985-09-01

    Three patients with Ehlers-Danlos syndrome were reported. Unusual findings on computed tomography were seen in two of the three patients. One case showed peculiar and marked dilatation of the 4th ventricle, supracerebellar cistern and lateral ventricle. The other case presented disproportionate enlargement of the anterior horn of the lateral ventricle. These CT findings in the two patients suggest that developmental abnormalities may constitute a structural defect.

  7. Measurement of liver volume by emission computed tomography

    International Nuclear Information System (INIS)

    Kan, M.K.; Hopkins, G.B.

    1979-01-01

    In 22 volunteers without clinical or laboratory evidence of liver disease, liver volume was determined using single-photon emission computed tomography (ECT). This technique provided excellent object contrast between the liver and its surroundings and permitted calculation of liver volume without geometric assumptions about the liver's configuration. Reproducibility of results was satisfactory, with a root-mean-square error of less than 6% between duplicate measurements in 15 individuals. The volume measurements were validated by the use of phantoms

  8. Computed tomography changes following cryotherapy for hepatic cancer

    Energy Technology Data Exchange (ETDEWEB)

    King, J.; Morris, D. L. [University of NSW, Sydney (Australia). Department of Surgery; Glenn, D. [St George Hospital, Kogarah, Sydney (Australia). Department of Radiology

    1997-05-01

    Encouraging survival and tumour marker results have been described in patients where the focally destructive technique, hepatic cryotherapy, is used to treat primary and secondary hepatic malignancy. Radiology allows assessment of the cryotherapy procedure and follow-up treatment. This paper aims to review and describe the appearance of hepatic cryotherapy by computed tomography which allows assessment of the adequacy of surgical technique and offers the ability to identify recurrences that may be suitable for further treatment. 11 refs., 1 tab., 9 figs.

  9. Computed tomography changes following cryotherapy for hepatic cancer

    International Nuclear Information System (INIS)

    King, J.; Morris, D. L.; Glenn, D.

    1997-01-01

    Encouraging survival and tumour marker results have been described in patients where the focally destructive technique, hepatic cryotherapy, is used to treat primary and secondary hepatic malignancy. Radiology allows assessment of the cryotherapy procedure and follow-up treatment. This paper aims to review and describe the appearance of hepatic cryotherapy by computed tomography which allows assessment of the adequacy of surgical technique and offers the ability to identify recurrences that may be suitable for further treatment

  10. Organ doses to examinees during photofluorography, fluoroscopy and computed tomography

    International Nuclear Information System (INIS)

    Kato, Kazuo; Antoku, Shigetoshi; Sawada, Shozo; Russell, W.J.; Wada, Takuro.

    1990-07-01

    Doses to the salivary glands, thyroid gland, breast, lung, stomach and colon during mass radiologic gastric screening, mass radiographic chest screening, upper gastrointestinal series, and computed tomography were determined by exposing a phantom female human to simulated radiological X-ray examinations in community hospitals. The doses were measured using thermoluminescent dosimeters, and the results will be used to document organ doses received by participants in the ABCC/RERF Adult Health Study. (author)

  11. Computed tomography of common congenital lesions of the temporal bone

    Energy Technology Data Exchange (ETDEWEB)

    Yuen, H.Y. E-mail: drhyyuen@doctors.org.uk; Ahuja, A.T.; Wong, K.T.; Yue, V.; Hasselt, A.C. van

    2003-09-01

    This pictorial review describes the application of high-resolution computed tomography to the investigation and pre-operative work-up of the common lesions of congenital hearing loss, including congenital aural dysplasia, various congenital ossicular anomalies, inner ear dysmorphology, large vestibular aqueduct syndrome, and congenital absence of cochlear nerve and labyrinthitis ossificans from previous infection. The aim is to help radiologists to provide a more accurate diagnosis of underlying aetiology and assist in surgical planning.

  12. Clinical applications of the computed tomography of the thorax

    International Nuclear Information System (INIS)

    Hong, Seong Eun; Kim, Ho Kyun; Kim, Soon Yong

    1980-01-01

    The computed tomography of the thorax has had considerably less impact in patient management than that of head and abdomen, because the convention chest radiography is a much more sensitive and accurate examination than the plain film studies of the head and abdomen. It has progressively been identified that the computed tomography of chest is superior to the conventional radiography in detection of small pulmonary nodules including occult metastatic lesions, in evaluation of character of hilar enlargement, and in staging of known bronchogenic caner. And especially in mediastinum, the computed tomography is supported to the any other conventional radiography in outlining lesions and determining character and extent of lesions. At the department of radiology, Kyung Hee University Hospital , 87 cases of computed tomography of chest were performed with EMI-CT 5005 whole-body scanner from October 1977 to August 1979. The results were as following; 1. The fifty eight cases of considered to be pathologic findings were 23 pleural thickening and/or effusion, 14 bronchogenic carcinoma, 8 inflammatory lesions of lung parenchyme, 6 mediastinal lesions, 3 metastinal lesions, 3 COPD, 1 trauma, respectively. 2. No gravity-dependent change was noted in patients with chronic obstructive pulmonary disease (COPD), which was frequently seen in normal subjects. Diminished numbers of pulmonary vessels was noted in COPD. 3. Small nodules in lung, retrosternal, posterior costophrenic and subpleural regions, which were not found on conventional radiography, can be detected by chest CT. 4. Differentiation of dilated central pulmonary artery from pulmonary mass in enlarged hilum and determination of adjacent mediastinal invasion, manifested by obliterated fat plane, was possible. 5. The cases of mediastinal widening such as paraspinal ilpomatosis, pericardial fat pad, teratoma, and bronchogenic cyst were easily determined by means of measuring the attenuation coefficiencies. 6. Small amount

  13. Endodontic practice management with cone-beam computed tomography

    OpenAIRE

    Priyank Sethi; Ritu Tiwari; Maneesha Das; Mahesh Pratap Singh; Manish Agarwal; Alfred Joseph Ravikumar

    2017-01-01

    Traditionally, conventional periapical radiology formed the backbone of endodontics for diagnosis, treatment planning, and management. One of the major associated gripes being the technique created two-dimensional images of three-dimensional (3D) structures, suffered magnification, superimposition, and distortion, leading to compromised diagnostic information. The need to analyze the area of interest in all the possible planes led to the introduction of cone-beam computed tomography (CBCT), a...

  14. Use of Cone Beam Computed Tomography in Endodontics

    Science.gov (United States)

    Scarfe, William C.; Levin, Martin D.; Gane, David; Farman, Allan G.

    2009-01-01

    Cone Beam Computed Tomography (CBCT) is a diagnostic imaging modality that provides high-quality, accurate three-dimensional (3D) representations of the osseous elements of the maxillofacial skeleton. CBCT systems are available that provide small field of view images at low dose with sufficient spatial resolution for applications in endodontic diagnosis, treatment guidance, and posttreatment evaluation. This article provides a literature review and pictorial demonstration of CBCT as an imaging adjunct for endodontics. PMID:20379362

  15. Cardiac Computed Tomography as an Imaging Modality in Coronary Anomalies.

    Science.gov (United States)

    Karliova, Irem; Fries, Peter; Schmidt, Jörg; Schneider, Ulrich; Shalabi, Ahmad; Schäfers, Hans-Joachim

    2018-01-01

    Coronary artery fistulae and coronary aneurysms are rare anomalies. When they become symptomatic, they require precise anatomic information to allow for planning of the therapeutic procedure. We report a case in which both fistulae and aneurysm were present. The required information could only be obtained by electrocardiogram-gated computed tomography with reformation. This imaging modality should be considered in every case of fistula or coronary aneurysm. Copyright © 2018 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.

  16. Findings of spinal diseases by improved recent computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Chuman, Hirokazu; Shinohara, Norio (National Central Hospital of Fukuoka (Japan)); Ono, Tetsuo; Noguchi, Yasuo; Morinaga, Masahiro; Sibata, Kenichiro; Akiyama, Tetsu

    1984-06-01

    In this study, the effectiveness of computed tomography in diagnosing several spinal disorders was evaluated. Since March, 1983, sixty five spinal disorders (cervical spondylosis 10, OPLL OYL 11, spinal canal stenosis 11, disc herniation 17, tumor 14) were scanned in our hospital and we found improvement in analysis of soft tissues, that is, disc herniation, thick yellow ligament and nerve tissue. This experience suggests that CT demonstrates the deformity and compression of nerve accurately.

  17. Computed tomography on renal masses in dogs and cats

    International Nuclear Information System (INIS)

    Yamazoe, Kazuaki; Ohashi, Fumihito; Kadosawa, Tsuyoshi; Nishimura, Ryohei; Sasaki, Nobuo; Takeuchi, Akira.

    1994-01-01

    Computed tomography (CT) was performed on renal tumors (Wilms' tumor and renal cell carcinoma) and renal cysts in dogs and cats. CT images in renal tumors were well correlated with macroscopic findings, and contrast CT images were quite useful in differentiating tumoral regions from non-tumoral ones. On renal cysts, intravenous pyelography and ultrasonography were as effective as CT images in morphological diagnosis, but CT was considered to be superior for evaluating three-dimensional (3-D) relationships in complicated lesions. (author)

  18. Computed tomography of lambdoid calvarial defect in neurofibromatosis

    International Nuclear Information System (INIS)

    Mann, H.; Kozic, Z.; Medinilla, O.R.

    1983-01-01

    A patient with neurofibromatosis is reported in whom cranial computed tomography (CT) revealed a calvarial defect with an associated soft-tissue mass in the region of the left lambdoid suture. This defect has been the subject of several previous reports, having been demonstrated by means of conventional skull radiography. It should be included in the differential diagnosis when a lytic calvarial lesion is found on CT. (orig.)

  19. Computed tomography of the heart using thallium-201 in children.

    Science.gov (United States)

    Treves, S; Hill, T C; VanPraagh, R; Holman, B L

    1979-09-01

    Thallium-201 emission computed tomography (ECT) was performed in 3 pediatric patients in whom conventional scintigraphy was normal but there was a strong clinical suspicion of myocardial disease. Abnormalities in the distribution of myocardial perfusion appeared sharply. Single photon ECT provides a three dimensional reconstruction which results in greater enhancement since activity in overlying structures does not interfere. Its widespread use is limited only by the cost of the imaging device.

  20. Application of C-arm computed tomography in cardiology

    International Nuclear Information System (INIS)

    Rieber, J.; Rohkohl, C.; Lauritsch, G.; Rittger, H.; Meissner, O.

    2009-01-01

    C-arm computed tomography is currently being introduced into cardiac imaging and offers the potential for three-dimensional imaging of the cardiac anatomy within the interventional environment. This detailed view is necessary to support complex interventional strategies, such as transcutaneous valve replacement, interventional therapy of atrial fibrillation, implantation of biventricular pacemakers and assessment of myocardial perfusion. Currently, the major limitation of this technology is its insufficient temporal resolution which limits the visualization of fast moving parts of the heart. (orig.) [de

  1. Measurement of radiation dose in multi-slice computed tomography

    OpenAIRE

    Surendra Maharjan; Sudil Prajapati; Om Biju Panta

    2016-01-01

    The aim of this study was to measure the radiation doses for computed tomography (CT) examinations of the head, chest and abdomen in adult patients in Nepal in comparison to international standard. Dose length products (DLP) and effective doses for standard patient sizes were calculated from the reported volume CT dose index (CTDIVol). Details were obtained from approximately 90 CT examinations carried out in 128 slice CT scan. Effective dose was calculated for each examination using CT dose ...

  2. Computed tomography of the heart using thallium-201 in children

    International Nuclear Information System (INIS)

    Treves, S.; Hill, T.C.; VanPraagh, R.; Holman, B.L.

    1979-01-01

    Thallium-201 emission computed tomography (ECT) was performed in 3 pediatric patients in whom conventional scintigraphy was normal but there was a strong clinical suspicion of myocardial disease. Abnormalities in the distribution of myocardial perfusion appeared sharply delineated with ECT compared to normal conventional gamma camera scintigraphy. Single photon ECT provides a three dimensional reconstruction which results in greater enhancement since activity in overlying structures does not interfere. Its widespread use is limited only by the cost of the imaging device

  3. Demand of Innovative Services on a Computed Tomography Scan

    OpenAIRE

    Na Ayudhya Chamaiporn Sudasna; Chandrachai Achara; Sitthiseripratip Kriskrai; Niparnan Nattee

    2016-01-01

    This paper seeks to investigate the needs of service, innovative Mobile Computed Tomography (CT) Scan service, from the leading level of Neurosurgeon in Bangkok, Thailand. The research is proposed investigating Neurosurgeon’s expectations for Mobile CT Scan and current problems of CT scan operating. This is a survey research approach, performing in-depth interview which collected data from 21 Neurosurgeons, 12 hospitals in Bangkok and surrounding areas. Due to the number of samples limited, t...

  4. Total variation superiorization schemes in proton computed tomography image reconstruction

    OpenAIRE

    Penfold, S. N.; Schulte, R. W.; Censor, Y.; Rosenfeld, A. B.

    2010-01-01

    Purpose: Iterative projection reconstruction algorithms are currently the preferred reconstruction method in proton computed tomography (pCT). However, due to inconsistencies in the measured data arising from proton energy straggling and multiple Coulomb scattering, noise in the reconstructed image increases with successive iterations. In the current work, we investigated the use of total variation superiorization (TVS) schemes that can be applied as an algorithmic add-on to perturbation-resi...

  5. Cone-beam computed tomography and the dentist.

    Science.gov (United States)

    MacDonald, David

    2017-02-01

    Although cone-beam computed tomography (CBCT) is just 15 years old, it has revolutionized the practice of dentistry, so much so, there is hardly a dental specialty which has not been affected by this technology. Nevertheless, it presents the dentist with a number of important challenges. An initial steep learning curve must be addressed without unnecessary exposure to the patient. This is particularly important when the patient is a child. © 2015 Wiley Publishing Asia Pty Ltd.

  6. Effect of oral contrast agents on computed tomography-based positron emission tomography attenuation correction in dual-modality positron emission tomography/computed tomography imaging.

    Science.gov (United States)

    Antoch, Gerald; Jentzen, Walter; Freudenberg, Lutz S; Stattaus, Jorg; Mueller, Stefan P; Debatin, Jorg F; Bockisch, Andreas

    2003-12-01

    To evaluate the effect of iodine- and barium-based contrast agents on the computed tomography (CT)-based positron emission tomography (PET) attenuation correction in dual-modality PET/CT. Experiments were conducted on a Society of Nuclear Medicine/National Electrical Manufacturers Association-PET phantom equipped with cylinders containing [18F]-2-fluoro-2-desoxy-D-glucose. The main compartment was filled with iodine (0.5-10%), barium (0.5-50%), or water (negative control). The error in attenuation correction was determined by comparison of measured tracer quantities in the presence of contrast agents with expected quantities. Contrast agent attenuation was demonstrated to be comparable to in vivo conditions. The presence of contrast agents resulted in an overestimation of the intracylindrical activity concentration on PET images and overestimation directly related to contrast concentrations (iodine 5-38%; barium 15-580%). Iodine and barium concentrations in clinical use resulted in an activity overestimation of 20 +/- 1.8% for iodine and 21 +/- 2.9% for barium. An overestimation of the tracer activity concentration is to be expected in the presence of oral contrast agents, if PET attenuation correction is attained CT-based.

  7. Computed Tomography and Computed Radiography of late Bronze Age Cremation Urns from Denmark

    DEFF Research Database (Denmark)

    Harvig, Lise Lock; Lynnerup, Niels; Amsgaard Ebsen, Jannie

    2012-01-01

    To improve methods used to study prehistoric cremation rituals, cremation urns from the Danish late Bronze Age were examined using Computed Tomography and Computed Radiography (Digital X-ray). During microexcavation, the digital images were used as registration tool. Our results suggest that oste...

  8. Morphological and Functional Evaluation of Quadricuspid Aortic Valves Using Cardiac Computed Tomography

    Energy Technology Data Exchange (ETDEWEB)

    Song, Inyoung; Park, Jung Ah; Choi, Bo Hwa; Ko, Sung Min [Department of Radiology, Konkuk University Medical Center, Konkuk University School of Medicine, Seoul 05030 (Korea, Republic of); Shin, Je Kyoun; Chee, Hyun Keun; Kim, Jun Seok [Department of Thoracic Surgery, Konkuk University Medical Center, Konkuk University School of Medicine, Seoul 05030 (Korea, Republic of)

    2016-11-01

    The aim of this study was to identify the morphological and functional characteristics of quadricuspid aortic valves (QAV) on cardiac computed tomography (CCT). We retrospectively enrolled 11 patients with QAV. All patients underwent CCT and transthoracic echocardiography (TTE), and 7 patients underwent cardiovascular magnetic resonance (CMR). The presence and classification of QAV assessed by CCT was compared with that of TTE and intraoperative findings. The regurgitant orifice area (ROA) measured by CCT was compared with severity of aortic regurgitation (AR) by TTE and the regurgitant fraction (RF) by CMR. All of the patients had AR; 9 had pure AR, 1 had combined aortic stenosis and regurgitation, and 1 had combined subaortic stenosis and regurgitation. Two patients had a subaortic fibrotic membrane and 1 of them showed a subaortic stenosis. One QAV was misdiagnosed as tricuspid aortic valve on TTE. In accordance with the Hurwitz and Robert's classification, consensus was reached on the QAV classification between the CCT and TTE findings in 7 of 10 patients. The patients were classified as type A (n = 1), type B (n = 3), type C (n = 1), type D (n = 4), and type F (n = 2) on CCT. A very high correlation existed between ROA by CCT and RF by CMR (r = 0.99) but a good correlation existed between ROA by CCT and regurgitant severity by TTE (r = 0.62). Cardiac computed tomography provides comprehensive anatomical and functional information about the QAV.

  9. Morphological and functional evaluation of quadricuspid aortic valves using cardiac computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Song, In Young; Park, Jung Ah; Choi, Bo Hwa; Ko, Sung Min; Shin, Je Kyoun; Chee, Hyun Keun; KIm, Jun Seok [Konkuk University Medical Center, Konkuk University School of Medicine, Seoul (Korea, Republic of)

    2016-07-15

    The aim of this study was to identify the morphological and functional characteristics of quadricuspid aortic valves (QAV) on cardiac computed tomography (CCT). We retrospectively enrolled 11 patients with QAV. All patients underwent CCT and transthoracic echocardiography (TTE), and 7 patients underwent cardiovascular magnetic resonance (CMR). The presence and classification of QAV assessed by CCT was compared with that of TTE and intraoperative findings. The regurgitant orifice area (ROA) measured by CCT was compared with severity of aortic regurgitation (AR) by TTE and the regurgitant fraction (RF) by CMR. All of the patients had AR; 9 had pure AR, 1 had combined aortic stenosis and regurgitation, and 1 had combined subaortic stenosis and regurgitation. Two patients had a subaortic fibrotic membrane and 1 of them showed a subaortic stenosis. One QAV was misdiagnosed as tricuspid aortic valve on TTE. In accordance with the Hurwitz and Robert's classification, consensus was reached on the QAV classification between the CCT and TTE findings in 7 of 10 patients. The patients were classified as type A (n = 1), type B (n = 3), type C (n = 1), type D (n = 4), and type F (n = 2) on CCT. A very high correlation existed between ROA by CCT and RF by CMR (r = 0.99) but a good correlation existed between ROA by CCT and regurgitant severity by TTE (r = 0.62). Cardiac computed tomography provides comprehensive anatomical and functional information about the QAV.

  10. Head and neck computed tomography virtual endoscopy: evaluation of a new imaging technique.

    Science.gov (United States)

    Gallivan, R P; Nguyen, T H; Armstrong, W B

    1999-10-01

    To evaluate a new radiographic imaging technique: computed tomography virtual endoscopy (CTVE) for head and neck tumors. Twenty-one patients presenting with head and neck masses who underwent axial computed tomography (CT) scan with contrast were evaluated by CTVE. Comparisons were made with video-recorded images and operative records to evaluate the potential utility of this new imaging technique. Twenty-one patients with aerodigestive head and neck tumors were evaluated by CTVE. One patient had a nasal cylindrical cell papilloma; the remainder, squamous cell carcinomas distributed throughout the upper aerodigestive tract. Patients underwent complete head and neck examination, flexible laryngoscopy, axial CT with contrast, CTVE, and in most cases, operative endoscopy. Available clinical and radiographic evaluations were compared and correlated to CTVE findings. CTVE accurately demonstrated abnormalities caused by intraluminal tumor, but where there was apposition of normal tissue against tumor, inaccurate depictions of surface contour occurred. Contour resolution was limited, and mucosal irregularity could not be defined. There was very good overall correlation between virtual images, flexible laryngoscopic findings, rigid endoscopy, and operative evaluation in cases where oncological resections were performed. CTVE appears to be most accurate in evaluation of subglottic and nasopharyngeal anatomy in our series of patients. CTVE is a new radiographic technique that provides surface-contour details. The technique is undergoing rapid technical evolution, and although the image quality is limited in situations where there is apposition of tissue folds, there are a number of potential applications for this new imaging technique.

  11. Anatomical structure of lingual foramen in cone beam computed tomography

    International Nuclear Information System (INIS)

    Ki, Min Woo; Hwang, Eui Hwan; Lee, Sang Rae

    2004-01-01

    To evaluate whether cone beam computed tomography can depict the distribution, position, frequency, relative vertical dimension, and the diameter of the lingual foramen and direction of lingual bone canal. Cone beam computed tomography of mandible was performed on 25 males and 25 females with no history of any orthodontic treatments or any other dental surgeries. A statistical comparison was done on the mean values of males and females. In the location and distribution of lingual foramina, median lingual foramen was found in all subjects and lateral lingual foramen in 58%. In the lateral lingual foramen, bilateral type was found in 28% and unilateral type in 30%. In the number of lingual foramina, median lingual foramen had two foramina and lateral lingual foramen had one foramen, mostly. In the relative mean vertical dimension of lingual foramina, median lingual foramen was 0.03 ± 0.08, and both lateral lingual foramina was 0.20 ± 0.04. The mean diameter of lingual foramina, median lingual foramen was 0.9 mm ± 0.28, right lateral lingual foramen was 0.92 mm ± 0.23, and left lateral lingual foramen was 0.88 mm ± 0.27. The most frequent direction of the lingual bone canals, median lingual bone canal proceeded in anteroinferior direction and lateral lingual bone canal in anterosuperolateral direction. Cone beam computed tomography can be helpful for surgery and implantation on the mandibular area. Radiologist should be aware of this anatomical feature and its possible implications.

  12. Computer tomography for TNM based radiation planning of urological tumours

    International Nuclear Information System (INIS)

    Ammon, J.; Karstens, J.H.; Ruebben, H.; Technische Hochschule Aachen

    1978-01-01

    From the extensive statistics concerning treatment results of urological tumours which are available from central tumour registers, a first draft of a treatment plan has been worked out, which is based on tumour spread. Since the extent of tumour invasion is documented by the TNM system of the UICC, one is justified in speaking of TNM orientated treatment planning. For planning it is necessary to consider not only tumour type and depth of infiltration of local tissues, but also the lymph node anatomy, whether the nodes are involved or not. Computer tomography assists significantly in the performance of such TNM orientated treatment planning, particularly in determining the extent of the volume to be irradiated. It must be stressed that computer tomography does not replace the use of simulators, but that it is a valuable addition. In our view, computer tomography has also an undoubted value in treatment planning of urological tumours where palliation only is the aim. It provides the possibility of checking the effect of the chosen treatment by a non-invasive diagnostic method. (orig.) [de

  13. Hepatic hemangiomas as diagnosed by ultrasonography and computed tomography

    International Nuclear Information System (INIS)

    Sachse, M.

    1987-01-01

    A total of 62 cases where the clinical diagnosis of hepatic hemangioma had been established during the period between 1981 and 1983 on the basis of computed tomography and sonography were subjected to retrospective analysis with the aim of evaluating the diagnostic reliability of these two methods. In 29 patients a typical distribution pattern of the contrast medium gave irrefutable evidence of the disease. Hemangiomas were predicted from the results of computed tomography for a further 5 patients with less revealing distribution patterns, although in 4 among these the preliminary diagnosis of hemangioma was disproved by additional diagnostic procedures (scintigraphy, laparoscopy, surgery and biopsy). Out of 16 patients, in which the hemangiomas were diagnosed from the typical patterns created by the contrast medium on the CT scans, 11 showed sonographic findings to confirm the presence of such tumours. This retrospective analysis showed that a correct and positive diagnosis could be established in no more than 7 patients on the basis of sonography alone, while 6 such diagnoses were definitely proven to be false-positive. As regards diagnostic accuracy, sonography clearly compares unfavourably with computed tomography. It may offer some advantages inasmuch as it requires no radiation exposure, is non-invasive and, last not least, less costly. (ECB) [de

  14. Dosimetry in abdominal imaging by 6-slice computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Rodrigues, Sonia Isabel [Hospital de Faro, EPE (Portugal); Abrantes, Antonio Fernando; Ribeiro, Luis Pedro; Almeida, Rui Pedro Pereira [University of Algarve (Portugal). School of Health. Dept. of Radiology

    2012-11-15

    Objective: To determine the effective dose in abdominal computed tomography imaging and to study the influence of patients' characteristics on the received dose. Materials and Methods: Dose values measurements were performed with an ionization chamber on phantoms to check the agreement between dose values and those presented by the computed tomography apparatus, besides their compliance with the recommended reference dose levels. Later, values of dose received by physically able patients submitted to abdominal computed tomography (n = 100) were measured and correlated with their anthropometric characteristics. Finally, the dose to organs was simulated with the Monte Carlo method using the CT-Expo V 1.5 software, and the effect of automatic exposure control on such examinations. Results: The main characteristics directly influencing the dose include the patients' body mass, abdominal perimeter and body mass index, whose correlation is linear and positive. Conclusion: The radiation dose received from abdominal CT scans depends on some patient's characteristics, and it is important to adjust the acquisition parameters to their dimensions (author)

  15. Diagnostic accuracy of (18) F-methylcholine positron emission tomography/computed tomography for intra- and extrahepatic hepatocellular carcinoma.

    Science.gov (United States)

    Bieze, Matthanja; Klümpen, Heinz-Josef; Verheij, Joanne; Beuers, Ulrich; Phoa, Saffire S K S; van Gulik, Thomas M; Bennink, Roelof J

    2014-03-01

    Diagnosis of hepatocellular carcinoma (HCC) primarily involves imaging. The aim of this study was to assess the accuracy of (18) F-fluorocholine ((18) F-FCH) positron emission tomography (PET) for detection of HCC and evaluation of extent of disease. Patients with HCC >1 cm were included between 2009 and July 2011, and follow-up closed in February 2013. Diagnosis was based on American Association for the Study of Liver Diseases criteria, and all patients underwent (18) F-FCH PET/computed tomography (CT) at baseline before treatment, 6 underwent a second PET/CT posttreatment, and 1 a third during follow-up. Whole-body PET and low-dose CT imaging were performed 15 minutes after (18) F-FCH injection. Evaluation of imaging was done with standardized uptake value (SUV) ratios: SUV maximum of the lesion divided by the SUV mean of surrounding tissue. Statistical analyses included descriptive analyses, receiver operating characteristic curve, McNemar's test, and Kaplan-Meier's test at 5% level of significance. Twenty-nine patients revealed 53 intrahepatic lesions. In 48 of 53 lesions, (18) F-FCH PET was positive (SUVratio , 1.95 ± 0.66; sensitivity, 88%; specificity, 100%). PET/CT showed uptake in 18 extrahepatic lesions and no uptake in 3 lesions affirmed non-HCC lesions; all lesions were confirmed with additional investigation (accuracy, 100%). In 17 of 29 patients, additional lesions were found on PET/CT imaging, with implications for treatment in 15 patients. Posttreatment PET/CT showed identical results, compared with standard treatment evaluation. This study shows additional value of (18) F-FCH PET/CT for patients with HCC. (18) F-FCH PET/CT has implications for staging, management, and treatment evaluation because of accurate assessment of extrahepatic disease. © 2014 by the American Association for the Study of Liver Diseases.

  16. Computed tomography myocardial perfusion vs {sup 15}O-water positron emission tomography and fractional flow reserve

    Energy Technology Data Exchange (ETDEWEB)

    Williams, Michelle C.; Dweck, Marc R.; Golay, Saroj K. [University of Edinburgh/British Heart Foundation Centre for Cardiovascular Science, Edinburgh (United Kingdom); Mirsadraee, Saeed; Weir, Nicholas W.; Fletcher, Alison; Lucatelli, Christophe; Reid, John H. [University of Edinburgh, Clinical Research Imaging Centre, Edinburgh (United Kingdom); MacGillivray, Tom; Van Beek, Edwin J.R.; Newby, David E. [University of Edinburgh/British Heart Foundation Centre for Cardiovascular Science, Edinburgh (United Kingdom); University of Edinburgh, Clinical Research Imaging Centre, Edinburgh (United Kingdom); Cruden, Nicholas L.; Henriksen, Peter A.; Uren, Neal [Edinburgh Heart Centre, Royal Infirmary of Edinburgh, Edinburgh (United Kingdom); McKillop, Graham; Patel, Dilip [Department of Radiology, Royal Infirmary of Edinburgh, Edinburgh (United Kingdom); Lima, Joao A.C. [Johns Hopkins Hospital, Departments of Medicine and Radiology, Baltimore, MD (United States)

    2017-03-15

    Computed tomography (CT) can perform comprehensive cardiac imaging. We compared CT coronary angiography (CTCA) and CT myocardial perfusion (CTP) with {sup 15}O-water positron emission tomography (PET) and invasive coronary angiography (ICA) with fractional flow reserve (FFR). 51 patients (63 (61-65) years, 80 % male) with known/suspected coronary artery disease (CAD) underwent 320-multidetector CTCA followed by ''snapshot'' adenosine stress CTP. Of these 22 underwent PET and 47 ICA/FFR. Obstructive CAD was defined as CTCA stenosis >50 % and CTP hypoperfusion, ICA stenosis >70 % or FFR <0.80. PET hyperaemic myocardial blood flow (MBF) was lower in obstructive than non-obstructive territories defined by ICA/FFR (1.76 (1.32-2.20) vs 3.11 (2.44-3.79) mL/(g/min), P < 0.001) and CTCA/CTP (1.76 (1.32-2.20) vs 3.12 (2.44-3.79) mL/(g/min), P < 0.001). Baseline and hyperaemic CT attenuation density was lower in obstructive than non-obstructive territories (73 (71-76) vs 86 (84-88) HU, P < 0.001 and 101 (96-106) vs 111 (107-114) HU, P 0.001). PET hyperaemic MBF corrected for rate pressure product correlated with CT attenuation density (r = 0.579, P < 0.001). There was excellent per-patient sensitivity (96 %), specificity (85 %), negative predictive value (90 %) and positive predictive value (94 %) for CTCA/CTP vs ICA/FFR. CT myocardial attenuation density correlates with {sup 15}O-water PET MBF. CTCA and CTP can accurately identify obstructive CAD. (orig.)

  17. Clinical utility of dental cone-beam computed tomography: current perspectives

    Directory of Open Access Journals (Sweden)

    Jaju PP

    2014-04-01

    Full Text Available Prashant P Jaju,1 Sushma P Jaju21Oral Medicine and Radiology, 2Conservative Dentistry and Endodontics, Rishiraj College of Dental Sciences and Research Center, Bhopal, IndiaAbstract: Panoramic radiography and computed tomography were the pillars of maxillofacial diagnosis. With the advent of cone-beam computed tomography, dental practice has seen a paradigm shift. This review article highlights the potential applications of cone-beam computed tomography in the fields of dental implantology and forensic dentistry, and its limitations in maxillofacial diagnosis.Keywords: dental implants, cone-beam computed tomography, panoramic radiography, computed tomography

  18. Efficient and effective regularised ART for computed tomography.

    Science.gov (United States)

    Buzmakov, Alexey; Nikolaev, Dmitry; Chukalina, Marina; Schaefer, Gerald

    2011-01-01

    Algebraic Reconstruction Technique (ART) is a widely employed method in computed tomography since it has certain advantages, such as allowing reconstruction of data with missing projections in some angle ranges, over other techniques such as Filtered Back Projection (FBP). Recently, a regularisation technique for ART, RegART, was introduced which provides greatly reduced noise levels. However, a serious drawback of both ART and RegART is the computational complexity of the methods. In this paper, we present a fast version of RegART, which makes use of nVidia's CUDA technology, and show that this approach performs favourably compared to FBP.

  19. Osteosarcoma and chondrosarcoma: radiographic differentiation by means of computed tomography

    International Nuclear Information System (INIS)

    Tossato, Patricia dos Santos; Pereira, Amanda Caceres; Cavalcanti, Marcelo Gusmao Paraiso

    2002-01-01

    The purpose of this paper was to associate and compare the radiographic patterns of osteosarcoma and those of chondrosarcoma by means of computed tomography (CT). Computed tomographs of five cases of osteosarcoma and five cases of chondrosarcoma of the head and neck region were analyzed. The sensitivity of CT was calculated based on the results of histopathological examinations. We concluded that CT can facilitate the establishment of the final diagnosis since it is possible to distinguish the individual characteristics of osteosarcomas and chondrosarcomas in that exam. (author)

  20. Dose Optimization for Computed Tomography Localizer Radiographs for Low-Dose Lung Computed Tomography Examinations.

    Science.gov (United States)

    Schmidt, Bernhard T; Hupfer, Martin; Saltybaeva, Natalia; Kolditz, Daniel; Kalender, Willi A

    2017-02-01

    Recent studies have shown a substantial reduction of radiation dose from computed tomography (CT) scans down to 0.1 mSv for lung cancer screening and cardiac examinations, when applying optimization techniques. Hence, CT localizer radiographs (LRs) might now be considered a significant contributor to the total dose of the CT examination. We investigated in our study the potential for reducing dose of the LRs by adapting the patient-specific acquisition parameters of the LR. Localizer radiographs covering the lungs were acquired on 2 clinical scanners (64 slices, conventional detector [CD]; 96 slices, fully integrated detector [ID]) for 3 semianthropomorphic phantoms, representing a slim, a normal, and an obese adult. Starting at 120-kV tube voltage and 250-mA current were reduced until the image quality of the LR, and thereby the accuracy of the automatic exposure control was compromised; this was defined as a deviation of measured attenuation values in the center of the LR of more than 5% from the reference values measured at the highest tube voltage and current. Subsequent Monte Carlo calculations on anthropomorphic phantoms were performed to calculate organ and effective dose values for the respective optimal settings. In addition, effective dose values normalized to CTDIvol for tube voltages ranging from 60 to 160 kV were determined for the different combinations of phantom sizes, sexes, and LR views to evaluate dose efficiency. For the CD scanner, the optimal LR settings depended strongly on phantom size. Higher tube voltage and current were necessary for the larger phantoms. The ID scanner showed uncompromised LR quality for all phantoms using the lowest possible tube voltage-tube current combination of 80 kV and 20 mA. Depending on patient size and LR direction, effective dose values for the optimal settings ranged from 6 to 53 μSv and 3 to 11 μSv for the CD and ID scanner, respectively. For the example of an anterior-posterior LR on a normal patient