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Sample records for bone ct scan

  1. Doctors Should Bone Up on CT Scan Cancer Risks

    Science.gov (United States)

    ... fullstory_159909.html Doctors Should Bone Up on CT Scan Cancer Risks Many not aware of exact radiation ... July 15, 2016 (HealthDay News) -- Doctors routinely order CT scans as diagnostic tools. But many are ill-informed ...

  2. CT Scans

    Science.gov (United States)

    ... cross-sectional pictures of your body. Doctors use CT scans to look for Broken bones Cancers Blood clots Signs of heart disease Internal bleeding During a CT scan, you lie still on a table. The table ...

  3. Normal SUV Values Measured from NaF18- PET/CT Bone Scan Studies

    OpenAIRE

    Aung Zaw Win; Carina Mari Aparici

    2014-01-01

    Objectives Cancer and metabolic bone diseases can alter the SUV. SUV values have never been measured from healthy skeletons in NaF18-PET/CT bone scans. The primary aim of this study was to measure the SUV values from normal skeletons in NaF18-PET/CT bone scans. Methods A retrospective study was carried out involving NaF18- PET/CT bone scans that were done at our institution between January 2010 to May 2012. Our excluding criteria was patients with abnormal real function and patients with past...

  4. CT-scanning of ancient Greenlandic Inuit temporal bones

    DEFF Research Database (Denmark)

    Homøe, P; Lynnerup, N; Videbaek, H

    1992-01-01

    Additional morphological evidence of former infectious middle ear disease (IMED) was found by CT-scanning in 5 of 6 Greenlandic Inuit crania strongly suspected for former IMED due to earlier examination revealing either bilateral hypocellularity or asymmetry of the pneumatized area of the temporal...

  5. CT scan

    Science.gov (United States)

    ... come from a CT scan. Some people have allergies to contrast dye. Let your doctor know if you have ... vein contains iodine. If you have an iodine allergy, a type of contrast may cause nausea or vomiting , sneezing , itching , or ...

  6. The value of spiral CT scan on fracture of ankle joint and tarsal bones

    International Nuclear Information System (INIS)

    Objective: To study the value of spiral CT scan on the fracture of ankle joint and tarsal bones. Methods: 43 cases with the fracture of ankle joint and tarsal bones were collected and analyzed. All the cases were examined by plain film radiography and spiral CT thin slice scan. Multi-planar reformation (MPR), surface shaded display (SSD) and other techniques of image post-processing were performed in 35 cases of them. Results: Spiral CT scan could demonstrate more fractures than plain film radiography in 28 cases(65.1%). There are 15 cases (34.9%) which are normal in plain film radiography but abnormal in Spiral CT scan. Spiral CT could demonstrate the different length, width, direction and number of linear low density shadow. SSD and MPR were performed again in the cases with avulsion fracture and fragmental fracture to demonstrate the fracture direction and the shape, size and location of fragments more clearly. Conclusion: Spiral CT thin slice scan with image post-processing techniques can play an important role in fracture of ankle joint and tarsal bones. (authors)

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

    DEFF Research Database (Denmark)

    Ding, Ming; Odgaard, A; Hvid, I

    1999-01-01

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

  8. Normal SUV values measured from NaF18- PET/CT bone scan studies.

    Directory of Open Access Journals (Sweden)

    Aung Zaw Win

    Full Text Available Cancer and metabolic bone diseases can alter the SUV. SUV values have never been measured from healthy skeletons in NaF18-PET/CT bone scans. The primary aim of this study was to measure the SUV values from normal skeletons in NaF18-PET/CT bone scans.A retrospective study was carried out involving NaF18- PET/CT bone scans that were done at our institution between January 2010 to May 2012. Our excluding criteria was patients with abnormal real function and patients with past history of cancer and metabolic bone diseases including but not limited to osteoporosis, osteopenia and Paget's disease. Eleven studies met all the criteria.The average normal SUVmax values from 11 patients were: cervical vertebrae 6.84 (range 4.38-8.64, thoracic vertebrae 7.36 (range 6.99-7.66, lumbar vertebrae 7.27 (range 7.04-7.72, femoral head 2.22 (range 1.1-4.3, humeral head 1.82 (range 1.2-2.9, mid sternum 5.51 (range 2.6-8.1, parietal bone 1.71 (range 1.3-2.4.According to our study, various skeletal sites have different normal SUV values. SUV values can be different between the normal bones and bones with tumor or metabolic bone disease. SUV can be used to quantify NaF-18 PET/CT studies. If the SUV values of the normal skeleton are known, they can be used in the characterization of bone lesions and in the assessment of treatment response to bone diseases.

  9. Multimodal imaging of the human temporal bone: A comparison of CT and optical scanning techniques

    Science.gov (United States)

    Voie, Arne H.; Whiting, Bruce; Skinner, Margaret; Neely, J. Gail; Lee, Kenneth; Holden, Tim; Brunsden, Barry

    2003-10-01

    A collaborative effort between Washington University in St. Louis and Spencer Technologies in Seattle, WA has been undertaken to create a multimodal 3D reconstruction of the human cochlea and vestibular system. The goal of this project is to improve the accuracy of in vivo CT reconstructions of implanted cochleae, and to expand the knowledge of high-resolution anatomical detail provided by orthogonal-plane optical sectioning (OPFOS). At WUSL, computed tomography (CT) images of the cochlea are used to determine the position of cochlear implant electrodes relative to target auditory neurons. The cochlear implant position is determined using pre- and post-operative CT scans. The CT volumes are cross-registered to align the semicircular canals and internal auditory canal, which have a unique configuration in 3-D space. The head of a human body donor was scanned with a clinical CT device, after which the temporal bones were removed, fixed in formalin and trimmed prior to scanning with a laboratory Micro CT scanner. Following CT, the temporal bones were sent to the OPFOS Imaging Lab at Spencer Technologies for a further analysis. 3-D reconstructions of CT and OPFOS imaging modalities were compared, and results are presented. [Work supported by NIDCD Grants R44-03623-5 and R01-00581-13.

  10. Automated bone removal in CT angiography : Comparison of methods based on single energy and dual energy scans

    NARCIS (Netherlands)

    van Straten, Marcel; Schaap, Michiel; Dijkshoorn, Marcel L.; Greuter, Marcel J.; van der Lugt, Aad; Krestin, Gabriel P.; Niessen, Wiro J.

    2011-01-01

    Purpose: To evaluate dual energy based methods for bone removal in computed tomography angiography (CTA) images and compare these with single energy based methods that use an additional, nonenhanced, CT scan. Methods: Four different bone removal methods were applied to CT scans of an anthropomorphic

  11. Alternative oblique head CT scanning technique reduces bone artifact and improves interpretability of brainstem anatomy

    Directory of Open Access Journals (Sweden)

    Sam Douglas Kampondeni

    2010-06-01

    Full Text Available Brainstem pathology due to infections, infarcts and tumors are common in developing countries, but neuroimaging technology in these resource-poor settings is often limited to single slice, and occasionally spiral, CT. Unlike multislice CT and MRI, single slice and spiral CT are compromised by bone artifacts in the posterior fossa due to the dense petrous bones, often making imaging of the brainstem non-diagnostic. With appropriate head positioning, the petrous ridges can be avoided with 40˚ sagittal oblique scans parallel to either petrous ridge. We describe an alternative sagittal oblique scanning technique that significantly reduces brainstem CT artifacts thereby improving clarity of anatomy. With Inst­itutional Ethical approval, 13 adult patients were enrolled (5 males; 39%. All patients had routine axial brain CT and sagittal oblique scans with no lesions found. Images were read by 2 readers who gave a score for amount of artefact and clarity of structures in the posterior fossa. The mean artifact score was higher for routine axial images compared to sagittal oblique (2.92 vs. 1.23; P<0.0001. The mean anatomical certainty scores for the brainstem were significantly better in the sagittal oblique views compared to routine axial (1.23 vs. 2.77; P<0.0001. No difference was found between the two techniques with respect to the fourth ventricle or the cerebellum (axial vs. sag oblique: 1.15 vs. 1.27; P=0.37. When using single slice CT, the sagittal oblique scanning technique is valuable in improving clarity of anatomy in the brainstem if axial images are non-diagnostic due to bone artifacts.

  12. Malignant pleural mesothelioma with heterologous osteoblastic differentiation: case report of the characteristic CT and bone scan findings

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Young Jun; Kim, Joung Sook; Kim, Ji Young; Choi, Soo Jeon; Choi, Sang Bong [Sanggye Paik Hospital, Inje University College of Medicine, Seoul (Korea, Republic of)

    2008-06-15

    Malignant pleural mesothelioma is an uncommon neoplasm which is accompanied extremely rarely by osteoblastic heterologous elements. The CT manifestations of this tumor have been reported in several references. And, to our knowledge, only one case report provides a description of the bone scan findings. Here, we report the case of a rapidly progressing malignant pleural mesothelioma with heterologous osteoblastic elements. A CT scan reveals diffuse irregular pleural thickening and very coarse nodular calcifications along the right pleura and major fissure. A bone scan revealed an area of extensive increased radioactivity consistent with the pleural calcifications on the CT scan in the right hemithorax. A follow-up CT scan performed 40 days later suggests the presence of rapidly progressing nodular coarse calcifications.

  13. Methodologies for Development of Patient Specific Bone Models from Human Body CT Scans

    Science.gov (United States)

    Chougule, Vikas Narayan; Mulay, Arati Vinayak; Ahuja, Bharatkumar Bhagatraj

    2016-06-01

    This work deals with development of algorithm for physical replication of patient specific human bone and construction of corresponding implants/inserts RP models by using Reverse Engineering approach from non-invasive medical images for surgical purpose. In medical field, the volumetric data i.e. voxel and triangular facet based models are primarily used for bio-modelling and visualization, which requires huge memory space. On the other side, recent advances in Computer Aided Design (CAD) technology provides additional facilities/functions for design, prototyping and manufacturing of any object having freeform surfaces based on boundary representation techniques. This work presents a process to physical replication of 3D rapid prototyping (RP) physical models of human bone from various CAD modeling techniques developed by using 3D point cloud data which is obtained from non-invasive CT/MRI scans in DICOM 3.0 format. This point cloud data is used for construction of 3D CAD model by fitting B-spline curves through these points and then fitting surface between these curve networks by using swept blend techniques. This process also can be achieved by generating the triangular mesh directly from 3D point cloud data without developing any surface model using any commercial CAD software. The generated STL file from 3D point cloud data is used as a basic input for RP process. The Delaunay tetrahedralization approach is used to process the 3D point cloud data to obtain STL file. CT scan data of Metacarpus (human bone) is used as the case study for the generation of the 3D RP model. A 3D physical model of the human bone is generated on rapid prototyping machine and its virtual reality model is presented for visualization. The generated CAD model by different techniques is compared for the accuracy and reliability. The results of this research work are assessed for clinical reliability in replication of human bone in medical field.

  14. The effect of scan parameters on cone beam CT trabecular bone microstructural measurements of the human mandible

    OpenAIRE

    Ibrahim, N; Parsa, A.; Hassan, B.; van der Stelt, P; Aartman, I.H.A.; Wismeijer, D.

    2014-01-01

    The objective of this study was to investigate the effect of different cone beam CT scan parameters on trabecular bone microstructure measurements. A human mandibular cadaver was scanned using a cone beam CT (3D Accuitomo 170; J.Morita, Kyota, Japan). 20 cone beam CT images were obtained using 5 different fields of view (4X4 cm, 6x6 cm, 8X8 cm, 10x10 cm and 10X5 cm), 2 types of rotation steps (180 degrees and 360 degrees) and 2 scanning resolutions (standard and high). Image analysis software...

  15. Assessment of the increased calcification of the jaw bone with CT-Scan after dental implant placement

    Energy Technology Data Exchange (ETDEWEB)

    Yunus, Barunawaty [Faculty of Dentistry, Hasanuddin University, Makassar (Malaysia)

    2011-06-15

    This study was performed to evaluate the changes of jaw bone density around the dental implant after placement using computed tomography scan (CT-Scan). This retrospective study consisted of 30 patients who had lost 1 posterior tooth in maxilla or mandible and installed dental implant. The patients took CT-Scan before and after implant placement. Hounsfield Unit (HU) was measured around the implants and evaluated the difference of HU before and after implant installation. The mean HU of jaw bone was 542.436 HU and 764.9 HU before and after implant placement, respectively (p<0.05). The means HUs for male were 632.3 HU and 932.2 HU and those for female 478.2 HU and 645.5 HU before and after implant placement, respectively (p<0.05). Also, the jaw bone with lower density needed longer period for implant procedure and the increased change of HU of jaw bone was less in the cases which needed longer period for osseointegration. CT-Scan could be used to assess the change of bone density around dental implants. Bone density around dental implant was increased after placement. The increased rate of bone density could be determined by the quality of jaw bone before implant placement.

  16. Assessment of the increased calcification of the jaw bone with CT-Scan after dental implant placement

    International Nuclear Information System (INIS)

    This study was performed to evaluate the changes of jaw bone density around the dental implant after placement using computed tomography scan (CT-Scan). This retrospective study consisted of 30 patients who had lost 1 posterior tooth in maxilla or mandible and installed dental implant. The patients took CT-Scan before and after implant placement. Hounsfield Unit (HU) was measured around the implants and evaluated the difference of HU before and after implant installation. The mean HU of jaw bone was 542.436 HU and 764.9 HU before and after implant placement, respectively (p<0.05). The means HUs for male were 632.3 HU and 932.2 HU and those for female 478.2 HU and 645.5 HU before and after implant placement, respectively (p<0.05). Also, the jaw bone with lower density needed longer period for implant procedure and the increased change of HU of jaw bone was less in the cases which needed longer period for osseointegration. CT-Scan could be used to assess the change of bone density around dental implants. Bone density around dental implant was increased after placement. The increased rate of bone density could be determined by the quality of jaw bone before implant placement.

  17. Comparing of image quality of axial and coronal CT scan of temporal bone

    Directory of Open Access Journals (Sweden)

    Ghanaati H

    2000-09-01

    Full Text Available CT image quality has been affected by many factors such as KVP, ma, exposure time, alogorithm and section thickness. Gantry tilt has the main role in visualization of the temporal bone anatomic structures. In this study, we tried to optimize these factors to determine the best gantry tilt. This study was performed on the human skull phantom and then extended to 15 patients. The phantom was made by inserting a normal human dry skull into a water- filled radiolucent cylindrical container. A lateral scout view was obtained and the OMBL (orbitomeatal baseline was used as the anatomical landmark.The phantom was scanned in 9, 15 , 30 , 45, 60 , 75, 90,105, 120 degree in relation to OMBL and 24 important anatomical structures were evaluated in each. Kilovoltage of 80, 120, 140 millimeters of 40, 70, 100, 120, 140, 170, 200, 240, exposue time of 2, 2, 4 second , algorithm of smooth, soft, standard, detail, bone adge and section thickness of 1.5, 3,5 millimeter were studied separately. In general, most of the anatomical structures are well demonstrated in 0 or 30 degrees of axial scans and 90 or 105 degrees in coronal scans. The best imaging techniques in Kv=140, Ma=100, S=2 seconds, algorithm of edge or bone, section thickness of 1.5 millimeter for small structures and 3 millineters for greater ones.The best 3-D image is provided by 3 millimeter slice thickness without overlapping but they couldn’t assist in diagnosis of our patient’s diseases. In indirect sagital reformatted images, the greater anatomical structures such as vestibule and cochlea are also shown, but they are recommended due to the slight degradation of the images and some loss of resolution.

  18. Prevalence of Clinically Significant Extraosseous Findings on Unenhanced CT Portions of 18F-Fluoride PET/CT Bone Scans

    Directory of Open Access Journals (Sweden)

    Chao-Jung Chen

    2012-01-01

    Full Text Available Objective. Due to the frequently interrupted supply of 99mTc-methylene diphosphonate, the use of 18F-fluoride positron emission tomography (PET/computed tomography (CT has become more popular. The study aims to determine the percentage of extraosseous findings from the unenhanced CT portion of 18F-fluoride PET/CT scans. Materials and Methods. We retrospectively collected 18F-fluoride PET/CT studies between March 2010 and February 2011. The unenhanced CT portions of 18F-fluoride PET/CT were reviewed for each patient. Significant extraosseous findings related to malignancy from the unenhanced CT were recorded. Results. A total of 158 patients (110 females, 48 males were included in the study. Clinically significant extraosseous findings from the unenhanced CT were found in 43 patients (27.2%. Previously unknown extraosseous findings were identified in 17 patients (10.8% after a review of the 18F-fluoride PET/CT scan results. Most of the extraosseous findings were small pulmonary metastases or enlarged metastatic lymph nodes. Conclusion. It is not rare to identify new clinically significant extraosseous findings from the unenhanced CT of 18F-fluoride PET/CT studies. Therefore the clinical management of patients may be altered by the results, and a careful review of the unenhanced CT portion of 18F-fluoride PET/CT is mandatory.

  19. F-18 fluoro-deoxy-glucose and F-18 sodium fluoride cocktail PET/CT scan in patients with breast cancer having equivocal bone SPECT/CT

    International Nuclear Information System (INIS)

    Although single-photon emission computed tomography (SPECT)/computed tomography (CT) plays a major role in the characterization of equivocal lesions on bone scintigraphy, it remains equivocal in a fraction of these patients. We evaluated the additional value of cocktail F-18 sodium fluoride (18F-NaF) and F-18 fluorodeoxyglucose (18F-FDG) co-injection positron emission tomography (PET) (cocktail PET) in these patients. Fifteen breast cancer patients, who had equivocal findings on the whole body bone scan (WBS) and SPECT/CT, were subjected to a cocktail PET/CT scan. The cocktail PET/CT was performed by co-administration of 18F-FDG and 18F-NaF in a ratio of about 2.4, with the total administered activity kept at approximately 10 mCi. Of the 15 patients, seven were with locally advanced breast cancer (LABC) and the other eight were referred because of suspicion of recurrent disease on follow-up. Of the seven patients with LABC, the cocktail PET scan was positive for all the lesions suspicious on WBS and SPECT/CT. Additionally, it showed uptake in the primary tumor and ipsilateral axillary lymph nodes as well as identified additional osseous, lymph nodal, and solid organ metastases in these patients. Similarly, of the eight patients studied for suspicion of recurrence, the cocktail PET scan was found to be positive in seven patients. In three patients, additional osseous lesions were noted. The cocktail PET/CT scan can characterize almost all the suspicious equivocal lesions on the bone scan and SPECT/CT. The distinct advantage of identifying lymph nodal and solid organ metastases allows it to be considered as a useful imaging modality in patients with equivocal bone SPECT/CT

  20. CT scan evaluation of glenoid bone and pectoralis major tendon: interest in shoulder prosthesis

    Science.gov (United States)

    Obert, Laurent; Peyron, Christelle; Boyer, Etienne; Menu, Gauthier; Loisel, François; Aubry, Sébastien

    2016-01-01

    Introduction: The shoulder arthroplasty brings satisfaction to patients in terms of quality of life and indolence. However whether anatomic implant or reverse, it does not escape from the loosening of the glenoid component. Moreover, optimal implantation is required to ensure the functional outcome without shortening of the arm. The purpose of this study is obtain CT scan evaluation of the glenoid bone stock in order to optimize glenoid component implantation and obtain a reference to determine optimal humeral component placement in case of humeral proximal fracture. Materials and methods: Between 2010 and 2011 we have analyzed 200 intact shoulder’s CT. We measured maximal and minimal width in the transverse plane of the glenoid, the distance from the pectoralis major (PM) tendon to the humeral head, the greater tubercle, change of curvature and the anatomical neck. Results: Mean maximum width was 27.4 ± 3.4 mm and mean minimum width was 15.5 ± 2.8 mm. Distances between upper edge of PM tendon to: humeral head, greater tubercle, change of curvature and anatomical neck were respectively: 67.6 ± 9.98 mm, 57.8 ± 10.3 mm, 28.7 ± 9 mm, and 34.2 ± 9.7 mm. Conclusion: Our study has produced an assessment of glenoid bone stock for optimal positioning of the glenoid implant but also to obtain a reference to determine the ideal location of the humeral component in the case of proximal humerus fracture. PMID:27716461

  1. Automated bone removal in CT angiography: Comparison of methods based on single energy and dual energy scans

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    Straten, Marcel van; Schaap, Michiel; Dijkshoorn, Marcel L.; Greuter, Marcel J.; Lugt, Aad van der; Krestin, Gabriel P.; Niessen, Wiro J. [Department of Radiology, Erasmus MC University Medical Center, P.O. Box 2040, 3000 CA Rotterdam (Netherlands); Departments of Radiology and Medical Informatics, Erasmus MC University Medical Center, P.O. Box 2040, 3000 CA Rotterdam (Netherlands); Department of Radiology, Erasmus MC University Medical Center, P.O. Box 2040, 3000 CA Rotterdam (Netherlands); Department of Radiology, University Medical Center Groningen, University of Groningen, P.O. Box 30.001, 9700 RB Groningen (Netherlands); Department of Radiology, Erasmus MC University Medical Center, P.O. Box 2040, 3000 CA Rotterdam (Netherlands); Departments of Radiology and Medical Informatics, Erasmus MC University Medical Center, P.O. Box 2040, 3000 CA Rotterdam (Netherlands)

    2011-11-15

    Purpose: To evaluate dual energy based methods for bone removal in computed tomography angiography (CTA) images and compare these with single energy based methods that use an additional, nonenhanced, CT scan. Methods: Four different bone removal methods were applied to CT scans of an anthropomorphic thorax phantom, acquired with a second generation dual source CT scanner. The methods differed by the way information on the presence of bone was obtained (either by using an additional, nonenhanced scan or by scanning with two tube voltages at the same time) and by the way the bone was removed from the CTA images (either by masking or subtracting the bone). The phantom contained parts which mimic vessels of various diameters in direct contact with bone. Both a quantitative and qualitative analysis of image quality after bone removal was performed. Image quality was quantified by the contrast-to-noise ratio (CNR) normalized to the square root of the dose (CNRD). At locations where vessels touch bone, the quality of the bone removal and the vessel preservation were visually assessed. The dual energy based methods were assessed with and without the addition of a 0.4 mm tin filter to the high voltage x-ray tube filtration. For each bone removal method, the dose required to obtain a certain CNR after bone removal was compared with the dose of a reference scan with the same CNR but without automated bone removal. The CNRD value of the reference scan was maximized by choosing the lowest tube voltage available. Results: All methods removed the bone completely. CNRD values were higher for the masking based methods than for the subtraction based methods. Single energy based methods had a higher CNRD value than the corresponding dual energy based methods. For the subtraction based dual energy method, tin filtration improved the CNRD value with approximately 50%. For the masking based dual energy method, it was easier to differentiate between iodine and bone when tin filtration

  2. CT scans and 3D reconstructions of Florida manatee (Trichechus manatus latirostris) heads and ear bones.

    Science.gov (United States)

    Chapla, Marie E; Nowacek, Douglas P; Rommel, Sentiel A; Sadler, Valerie M

    2007-06-01

    The auditory anatomy of the Florida manatee (Trichechus manatus latirostris) was investigated using computerized tomography (CT), three-dimensional reconstructions, and traditional dissection of heads removed during necropsy. The densities (kg/m3) of the soft tissues of the head were measured directly using the displacement method and those of the soft tissues and bone were calculated from CT measurements (Hounsfield units). The manatee's fatty tissue was significantly less dense than the other soft tissues within the head (p<0.05). The squamosal bone was significantly less dense than the other bones of the head (p<0.05). Measurements of the ear bones (tympanic, periotic, malleus, incus, and stapes) collected during dissection revealed that the ossicular chain was overly massive for the mass of the tympanoperiotic complex. PMID:17420106

  3. Template-based automatic extraction of the joint space of foot bones from CT scan

    Science.gov (United States)

    Park, Eunbi; Kim, Taeho; Park, Jinah

    2016-03-01

    Clean bone segmentation is critical in studying the joint anatomy for measuring the spacing between the bones. However, separation of the coupled bones in CT images is sometimes difficult due to ambiguous gray values coming from the noise and the heterogeneity of bone materials as well as narrowing of the joint space. For fine reconstruction of the individual local boundaries, manual operation is a common practice where the segmentation remains to be a bottleneck. In this paper, we present an automatic method for extracting the joint space by applying graph cut on Markov random field model to the region of interest (ROI) which is identified by a template of 3D bone structures. The template includes encoded articular surface which identifies the tight region of the high-intensity bone boundaries together with the fuzzy joint area of interest. The localized shape information from the template model within the ROI effectively separates the bones nearby. By narrowing the ROI down to the region including two types of tissue, the object extraction problem was reduced to binary segmentation and solved via graph cut. Based on the shape of a joint space marked by the template, the hard constraint was set by the initial seeds which were automatically generated from thresholding and morphological operations. The performance and the robustness of the proposed method are evaluated on 12 volumes of ankle CT data, where each volume includes a set of 4 tarsal bones (calcaneus, talus, navicular and cuboid).

  4. Percutaneous Bone Biopsies: Comparison between Flat-Panel Cone-Beam CT and CT-Scan Guidance

    Energy Technology Data Exchange (ETDEWEB)

    Tselikas, Lambros, E-mail: lambros.tselikas@gmail.com; Joskin, Julien, E-mail: j.joskin@gmail.com [Gustave Roussy, Interventional Radiology Department (France); Roquet, Florian, E-mail: florianroquet@hotmail.com [Gustave Roussy, Biostatistics Department (France); Farouil, Geoffroy, E-mail: g.farouil@gmail.com [Gustave Roussy, Interventional Radiology Department (France); Dreuil, Serge, E-mail: serge.dreuil@gustaveroussy.fr [Gustave Roussy, Medical Physics Department (France); Hakimé, Antoine, E-mail: thakime@yahoo.com; Teriitehau, Christophe, E-mail: cteriitehau@me.com [Gustave Roussy, Interventional Radiology Department (France); Auperin, Anne, E-mail: anne.auperin@gustaveroussy.fr [Gustave Roussy, Biostatistics Department (France); Baere, Thierry de, E-mail: thierry.debaere@gustaveroussy.fr; Deschamps, Frederic, E-mail: frederic.deschamps@gustaveroussy.fr [Gustave Roussy, Interventional Radiology Department (France)

    2015-02-15

    PurposeThis study was designed to compare the accuracy of targeting and the radiation dose of bone biopsies performed either under fluoroscopic guidance using a cone-beam CT with real-time 3D image fusion software (FP-CBCT-guidance) or under conventional computed tomography guidance (CT-guidance).MethodsSixty-eight consecutive patients with a bone lesion were prospectively included. The bone biopsies were scheduled under FP-CBCT-guidance or under CT-guidance according to operating room availability. Thirty-four patients underwent a bone biopsy under FP-CBCT and 34 under CT-guidance. We prospectively compared the two guidance modalities for their technical success, accuracy, puncture time, and pathological success rate. Patient and physician radiation doses also were compared.ResultsAll biopsies were technically successful, with both guidance modalities. Accuracy was significantly better using FP-CBCT-guidance (3 and 5 mm respectively: p = 0.003). There was no significant difference in puncture time (32 and 31 min respectively, p = 0.51) nor in pathological results (88 and 88 % of pathological success respectively, p = 1). Patient radiation doses were significantly lower with FP-CBCT (45 vs. 136 mSv, p < 0.0001). The percentage of operators who received a dose higher than 0.001 mSv (dosimeter detection dose threshold) was lower with FP-CBCT than CT-guidance (27 vs. 59 %, p = 0.01).ConclusionsFP-CBCT-guidance for bone biopsy is accurate and reduces patient and operator radiation doses compared with CT-guidance.

  5. A three-dimensional reconstruction of the temporal bone by the helical scanning CT and its clinical application

    Energy Technology Data Exchange (ETDEWEB)

    Yonekawa, Hiroyuki; Ohashi, Masami; Miyashita, Souji; Gotoh, Mizuho; Nemoto, Satohiko; Kikuchi, Hideki (Azabu Triology Hospital, Sapporo (Japan)); Sakai, Noboru; Inuyama, Yukio

    1993-09-01

    The current availability of 3 dimensional (3-D) imaging from Computed Tomography (CT) has yielded new anatomical information and pre- and postoperative evaluations. However, little discussion as to the 3-D structural image of the temporal bone has been reported because conventional CT does provide sufficient data to produce such images. The helical scanning CT gathers continuous and multiple slice image data since it consists of an X-ray tube that continuously rotates around the patient while the patient moves continuously into the CT scanner. Thus, application of the helical scanning CT has made it possible to reconstruct 3-D images of the minute and complicated structure of the temporal bone. We evaluated 3-D images from 9 typical cases, examined from February to October 1992. As a result, we found that the 3-D images reconstructed with this system are useful for evaluation of the postoperative state of tympanoplasty, the diagnosis of anomalies of the bony labyrinth, and examining the extent of bone destruction induced by trauma, cholesteatoma, etc. (author).

  6. [Bone scanning with sodium 18F-fluoride PET and PET/CT. German guideline Version 1.0.].

    Science.gov (United States)

    Hellwig, D; Krause, B-J; Schirrmeister, H; Freesmeyer, M

    2010-01-01

    In nuclear medicine, bone scanning is based on the principle of scintigraphy using bone-seeking radiopharmaceuticals which accumulate in sites of increased bone formation. From a historical point of view, (18)F-fluoride was one of the first osteotropic tracers which was replaced by (99m)Tc-labelled polyphosphonates. With the development of modern PET equipment the superior diagnostic performance of (18)F-fluoride PET for the detection and characterization of osseous lesions was proven in comparison to conventional bone scanning. Recently, its importance as a substitute of conventional skeletal scintigraphy increased in a time with limited availability of (99)Mo/(99m)Tc. To ensure health care during this period, (18)F-fluoride PET currently became part of common outpatient care. This guideline comprehends recommendations on indications, protocols, interpretation and reporting of (18)F-fluoride PET and PET/CT. PMID:20838734

  7. Imaging non-specific wrist pain: interobserver agreement and diagnostic accuracy of SPECT/CT, MRI, CT, bone scan and plain radiographs.

    Directory of Open Access Journals (Sweden)

    Martin W Huellner

    Full Text Available PURPOSE: Chronic hand and wrist pain is a common clinical issue for orthopaedic surgeons and rheumatologists. The purpose of this study was 1. To analyze the interobserver agreement of SPECT/CT, MRI, CT, bone scan and plain radiographs in patients with non-specific pain of the hand and wrist, and 2. to assess the diagnostic accuracy of these imaging methods in this selected patient population. MATERIALS AND METHODS: Thirty-two consecutive patients with non-specific pain of the hand or wrist were evaluated retrospectively. All patients had been imaged by plain radiographs, planar early-phase imaging (bone scan, late-phase imaging (SPECT/CT including bone scan and CT, and MRI. Two experienced and two inexperienced readers analyzed the images with a standardized read-out protocol. Reading criteria were lesion detection and localisation, type and etiology of the underlying pathology. Diagnostic accuracy and interobserver agreement were determined for all readers and imaging modalities. RESULTS: The most accurate modality for experienced readers was SPECT/CT (accuracy 77%, followed by MRI (56%. The best performing, though little accurate modality for inexperienced readers was also SPECT/CT (44%, followed by MRI and bone scan (38% each. The interobserver agreement of experienced readers was generally high in SPECT/CT concerning lesion detection (kappa 0.93, MRI 0.72, localisation (kappa 0.91, MRI 0.75 and etiology (kappa 0.85, MRI 0.74, while MRI yielded better results on typification of lesions (kappa 0.75, SPECT/CT 0.69. There was poor agreement between experienced and inexperienced readers in SPECT/CT and MRI. CONCLUSIONS: SPECT/CT proved to be the most helpful imaging modality in patients with non-specific wrist pain. The method was found reliable, providing high interobserver agreement, being outperformed by MRI only concerning the typification of lesions. We believe it is beneficial to integrate SPECT/CT into the diagnostic imaging algorithm of

  8. Knee CT scan

    Science.gov (United States)

    Risks of CT scans include: Exposure to radiation Allergy to contrast dye CT scans give off more radiation than ... injected contrast dye. The most common type of contrast contains ... you have this an iodine allergy. If you need to have this kind of ...

  9. Bone Densitometry (Bone Density Scan)

    Science.gov (United States)

    ... of DXA Bone Densitometry? What is a Bone Density Scan (DXA)? Bone density scanning, also called dual-energy x-ray absorptiometry ( ... is today's established standard for measuring bone mineral density (BMD). An x-ray (radiograph) is a noninvasive ...

  10. Semiautomated three-dimensional segmentation software to quantify carpal bone volume changes on wrist CT scans for arthritis assessment.

    Science.gov (United States)

    Duryea, J; Magalnick, M; Alli, S; Yao, L; Wilson, M; Goldbach-Mansky, R

    2008-06-01

    Rapid progression of joint destruction is an indication of poor prognosis in patients with rheumatoid arthritis. Computed tomography (CT) has the potential to serve as a gold standard for joint imaging since it provides high resolution three-dimensional (3D) images of bone structure. The authors have developed a method to quantify erosion volume changes on wrist CT scans. In this article they present a description and validation of the methodology using multiple scans of a hand phantom and five human subjects. An anthropomorphic hand phantom was imaged with a clinical CT scanner at three different orientations separated by a 30-deg angle. A reader used the semiautomated software tool to segment the individual carpal bones of each CT scan. Reproducibility was measured as the root-mean-square standard deviation (RMMSD) and coefficient of variation (CoV) between multiple measurements of the carpal volumes. Longitudinal erosion progression was studied by inserting simulated erosions in a paired second scan. The change in simulated erosion size was calculated by performing 3D image registration and measuring the volume difference between scans in a region adjacent to the simulated erosion. The RMSSD for the total carpal volumes was 21.0 mm3 (CoV = 1.3%) for the phantom, and 44.1 mm3 (CoV = 3.0%) for the in vivo subjects. Using 3D registration and local volume difference calculations, the RMMSD was 1.0-3.0 mm3 The reader time was approximately 5 min per carpal bone. There was excellent agreement between the measured and simulated erosion volumes. The effect of a poorly measured volume for a single erosion is mitigated by the large number of subjects that would comprise a clinical study and that there will be many erosions measured per patient. CT promises to be a quantifiable tool to measure erosion volumes and may serve as a gold standard that can be used in the validation of other modalities such as magnetic resonance imaging.

  11. Pediatric CT Scans

    Science.gov (United States)

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

  12. Abdominal CT scan

    Science.gov (United States)

    ... than regular x-rays. Many x-rays or CT scans over time may increase your risk for cancer. However, the risk from any one scan is small. Talk to your doctor about this risk and the benefit of the test for getting a correct diagnosis ...

  13. Pelvic CT scan

    Science.gov (United States)

    ... Abscess (collection of pus) Bladder stones Broken bone Cancer Diverticulitis ... scans over time may increase your risk of cancer. But the risk from any ... to contrast dye. Let your provider know if you have ever ...

  14. Sinus CT scan

    Science.gov (United States)

    ... may be due to: Birth defects Bone fractures Cancer Polyps in the sinuses Sinus infection (sinusitis) ... scans over time may increase your risk for cancer. However, the risk ... to contrast dye. Let your provider know if you have ever ...

  15. Visualization of postoperative anterior cruciate ligament reconstruction bone tunnels: Reliability of standard radiographs, CT scans, and 3D virtual reality images

    NARCIS (Netherlands)

    D.E. Meuffels (Duncan); J.W. Potters (Jan Willem); A.H.J. Koning (Anton); C.H. Brown Jr Jr. (Charles); J.A.N. Verhaar (Jan); M. Reijman (Max)

    2011-01-01

    textabstractBackground and purpose: Non-anatomic bone tunnel placement is the most common cause of a failed ACL reconstruction. Accurate and reproducible methods to visualize and document bone tunnel placement are therefore important. We evaluated the reliability of standard radiographs, CT scans, a

  16. Comparative study on measured variables and sensitivity to bone microstructural changes induced by weightlessness between in vivo and ex vivo micro-CT scans.

    Science.gov (United States)

    Sun, Lian Wen; Wang, Chao; Pu, Fang; Li, De Yu; Niu, Hai Jun; Fan, Yu Bo

    2011-01-01

    Depending on the experimental design, micro-CT can be used to examine bones either in vivo or ex vivo (excised fresh or formalin-fixed). In this study we investigated if differences exist in the variables measured by micro-CT between in vivo and ex vivo scans and which kind of scan is more sensitive to the changes of bone microstructure induced by simulated weightlessness. Rat tail suspension was used to simulate the weightless condition. The same bone from either normal or tail-suspended rats was scanned by micro-CT both in vivo and ex vivo (fresh and fixed by formalin). Then, bone mineral density (BMD) and microstructural characteristics were analyzed. The results showed that no significant differences existed in the microstructural parameters of trabecular bone among in vivo, fresh, and formalin-fixed bone scans from both femurs and tibias, although BMD exhibited differences. On the other hand, most parameters of the tail-suspended rats measured by micro-CT deteriorated compared with controls. Ex vivo scanning appeared to be more sensitive to bone microstructural changes induced by tail suspension than in vivo scanning. In general, the results indicate that values obtained in vivo and ex vivo (fresh and fixed) are comparable, thus allowing for meaningful comparison of experimental results from different studies irrespective of the type of scans. In addition, this study suggests that it is better to use ex vivo scanning when evaluating bone microstructure under weightlessness. However, researchers can select any type of scan depending upon the objective and the demands of the experiment.

  17. Bone scan in rheumatology

    International Nuclear Information System (INIS)

    In this chapter a revision is made concerning different uses of bone scan in rheumatic diseases. These include reflex sympathetic dystrophy, osteomyelitis, spondyloarthropaties, metabolic bone diseases, avascular bone necrosis and bone injuries due to sports. There is as well some comments concerning pediatric pathology and orthopedics. (authors). 19 refs., 9 figs

  18. Assessment of Corticotomy Facilitated Tooth Movement and Changes in Alveolar Bone Thickness - A CT Scan Study

    OpenAIRE

    Bhattacharya, Preeti; Bhattacharya, Hirak; Anjum, Arbab; Bhandari, Ravi; Agarwal, D. K.; Gupta, Ankur; Ansar, Juhi

    2014-01-01

    Introduction: Corticotomy is an effective method of accelerating the orthodontic treatment. The aim of this study was to compare the treatment time for the extraction space closure, between corticotomy assisted and conventional orthodontic tooth movement and to check the alveolar bone thickness before and after corticotomy procedure in the corticotomy group.

  19. Technical aspects of CT scanning.

    Science.gov (United States)

    Maravilla, K R; Pastel, M S

    1978-01-01

    The advent of computed tomography (CT) has initiated a technological revolution which continues to the present time. A brief review of basic principles of CT scanning is presented, and the evolution of modern CT scanner systems is traced. Some early indications of future trends are also presented.

  20. Pictorial review of MRI/CT Scan in congenital temporal bone anomalies, in patients for cochlear implant

    International Nuclear Information System (INIS)

    High-resolution CT scan (HRCT) and MRI are routinely performed prior to cochlear implant surgery. These modalities help assess the status of the inner ear structures. A few patients have significant anomalies, which need to be assessed and understood in detail. We present a pictorial essay of these anomalies and described our HRCT and MRI techniques in patients being imaged prior to surgery

  1. Children, CT Scan and Radiation

    OpenAIRE

    Morteza Bajoghli; Farshad Bajoghli; Nazila Tayari; Reza Rouzbahani

    2010-01-01

    Children are more sensitive to radiation than adults. Computer-ized tomography (CT) consists of 25 % of all medical imaging. It was estimated that more than 2% of all carcinomas in the USA are due to CT scans. There is an ongoing focus on the reduction of CT scan radiation dose. Awareness about risk-benefits of CT has increased. Reduction of radiological exam is an important issue because the accumulation effects of radiation can be hazardous. In addition, proper protocol should be followed f...

  2. {sup 99m}Tc-HDP Pinhole Bone Scan Features of Undetached Osteochondritis Dissecans of the Femoral Condyle: Report of a Case with Radiography, CT, and MRI Correlation

    Energy Technology Data Exchange (ETDEWEB)

    Bahk, Yong Whee [Sung Ae Hospital, Seoul (Korea, Republic of); Choi, Woo Hee [Seoul St. Mary' s Hospital, Catholic University Medical School, Seoul (Korea, Republic of)

    2009-02-15

    OCD may be initiated by arrest of bone growth and subchondral osteosclerosis followed by either cartilage hypertrophy with calcification or enfolding with osteochondral bridging. Diagnosis can be made in most instances using magnetic resonance imaging (MRI) or computed tomography (CT) or invasive arthroscopy. As to usefulness of conventional radiography (CR) opinions diverge as some held it to be of limited value while others valuable. The controversy seems to be due to semantic confusion of OCD from osteonecrosis (ON) which are different entities. This report will describe a case of undetached OCD occurred in the medial femoral condyle in a middle-aged female. It was free of symptom and incidentally discovered on {sup 99m}Tc-HDP pinhole scan performed for patellar injury. Pinhole scan findings of OCD are correlated to those of CR, CT, and MRI. An electronic search of literature failed to reveal earlier publication of bone scan features of undetached OCD. Pathologically, OCD differs from ON in that the fragment in the former condition comes off from a normal vascular bony bed while that in the latter separates from an avascular bony bed. Indeed, bone fragment in ON is devascularized but that in OCD maintains vascularity until weighted images, respectively and the halo showed low signal intensity on both T1 and T2 images.

  3. Using PET/CT Bone Scan Dynamic Data to Evaluate Tibia Remodeling When a Taylor Spatial Frame Is Used: Short and Longer Term Differences

    Science.gov (United States)

    Lundblad, Henrik; Maguire, Gerald Q.; Karlsson-Thur, Charlotte; Jonsson, Cathrine; Noz, Marilyn E.; Zeleznik, Michael P.; Jacobsson, Hans; Weidenhielm, Lars

    2015-01-01

    Eighteen consecutive patients, treated with a Taylor Spatial Frame for complex tibia conditions, gave their informed consent to undergo Na18F− PET/CT bone scans. We present a Patlak-like analysis utilizing an approximated blood time-activity curve eliminating the need for blood aliquots. Additionally, standardized uptake values (SUV) derived from dynamic acquisitions were compared to this Patlak-like approach. Spherical volumes of interest (VOIs) were drawn to include broken bone, other (normal) bone, and muscle. The SUVm(t) (m = max, mean) and a series of slopes were computed as (SUVm(ti) − SUVm(tj))/(ti − tj), for pairs of time values ti and tj. A Patlak-like analysis was performed for the same time values by computing ((VOIp(ti)/VOIe(ti))−(VOIp(tj)/VOIe(tj)))/(ti − tj), where p = broken bone, other bone, and muscle and e = expected activity in a VOI. Paired comparisons between Patlak-like and SUVm slopes showed good agreement by both linear regression and correlation coefficient analysis (r = 84%, rs = 78%-SUVmax, r = 92%, and rs = 91%-SUVmean), suggesting static scans could substitute for dynamic studies. Patlak-like slope differences of 0.1 min−1 or greater between examinations and SUVmax differences of ~5 usually indicated good remodeling progress, while negative Patlak-like slope differences of −0.06 min−1 usually indicated poor remodeling progress in this cohort. PMID:26436093

  4. Using PET/CT Bone Scan Dynamic Data to Evaluate Tibia Remodeling When a Taylor Spatial Frame Is Used: Short and Longer Term Differences

    Directory of Open Access Journals (Sweden)

    Henrik Lundblad

    2015-01-01

    Full Text Available Eighteen consecutive patients, treated with a Taylor Spatial Frame for complex tibia conditions, gave their informed consent to undergo Na18F− PET/CT bone scans. We present a Patlak-like analysis utilizing an approximated blood time-activity curve eliminating the need for blood aliquots. Additionally, standardized uptake values (SUV derived from dynamic acquisitions were compared to this Patlak-like approach. Spherical volumes of interest (VOIs were drawn to include broken bone, other (normal bone, and muscle. The SUVm(t (m=max, mean and a series of slopes were computed as (SUVm(ti-SUVm(tj/(ti-tj, for pairs of time values ti and tj. A Patlak-like analysis was performed for the same time values by computing ((VOIp(ti/VOIe(ti-(VOIp(tj/VOIe(tj/(ti-tj, where p = broken bone, other bone, and muscle and e = expected activity in a VOI. Paired comparisons between Patlak-like and SUVm slopes showed good agreement by both linear regression and correlation coefficient analysis (r=84%,rs=78%-SUVmax,r=92%, and rs=91%-SUVmean, suggesting static scans could substitute for dynamic studies. Patlak-like slope differences of 0.1 min−1 or greater between examinations and SUVmax differences of ~5 usually indicated good remodeling progress, while negative Patlak-like slope differences of −0.06 min−1 usually indicated poor remodeling progress in this cohort.

  5. 全身骨显像与CT对儿童神经母细胞瘤骨转移的诊断价值%Comparison of whole body bone scan and CT in diagnosing bone metastases of neuroblastoma in children

    Institute of Scientific and Technical Information of China (English)

    焦建国; 孙珂

    2012-01-01

    目的:比较全身骨显像及CT对儿童神经母细胞瘤骨转移的诊断价值.方法:选取经病理、影像学检查或临床随访等证实合并有骨转移的56例神经母细胞瘤患儿,比较全身骨显像及CT诊断神经母细胞瘤骨转移的阳性率.结果:全身骨显像与CT诊断神经母细胞瘤患儿骨转移一致性差(kappa=0.231,P=0.007);全身骨显像与CT诊断骨转移阳性率分别为91.1%和57.1%.结论:两种方法均可诊断神经母细胞瘤骨转移,但全身骨显像的诊断效能优于CT.%Aim: To compare the value of whole body bone scan ( WBS) and CT in diagnosing bone metastases of neuroblastoma in children. Methods: A total of 56 children who were formerly confirmed as bone metastasis by pathology , video-imaging or clinical follow-up, performed WBS and CT,respectively. The positive rate of the two methods in diagnosing bone metastases of neuroblastoma was compared. Results: Consistency of WBS and CT in diagnosing bone metastasis of neuroblastoma was poor ( kappa = 0. 231 , P = 0. 007 ) , and the positive rate was 91.1% and 57. 1% , respectively. Conclusion: Bone metastasis of neuroblastoma can be diagnosed by both WBS and CT ; diagnostic efficiency of WBS is higher than CT.

  6. TU-C-12A-12: Differentiating Bone Lesions and Degenerative Joint Disease in NaF PET/CT Scans Using Machine Learning

    International Nuclear Information System (INIS)

    Purpose: [F-18]NaF PET can be used to image bone metastases; however, tracer uptake in degenerative joint disease (DJD) often appears similar to metastases. This study aims to develop and compare different machine learning algorithms to automatically identify regions of [F-18]NaF scans that correspond to DJD. Methods: 10 metastatic prostate cancer patients received whole body [F-18]NaF PET/CT scans prior to treatment. Image segmentation resulted in 852 ROIs, 69 of which were identified by a nuclear medicine physician as DJD. For all ROIs, various PET and CT textural features were computed. ROIs were divided into training and testing sets used to train eight different machine learning classifiers. Classifiers were evaluated based on receiver operating characteristics area under the curve (AUC), sensitivity, specificity, and positive predictive value (PPV). We also assessed the added value of including CT features in addition to PET features for training classifiers. Results: The training set consisted of 37 DJD ROIs with 475 non-DJD ROIs, and the testing set consisted of 32 DJD ROIs with 308 non-DJD ROIs. Of all classifiers, generalized linear models (GLM), decision forests (DF), and support vector machines (SVM) had the best performance. AUCs of GLM (0.929), DF (0.921), and SVM (0.889) were significantly higher than the other models (p<0.001). GLM and DF, overall, had the best sensitivity, specificity, and PPV, and gave a significantly better performance (p<0.01) than all other models. PET/CT GLM classifiers had higher AUC than just PET or just CT. GLMs built using PET/CT information had superior or comparable sensitivities, specificities and PPVs to just PET or just CT. Conclusion: Machine learning algorithms trained with PET/CT features were able to identify some cases of DJD. GLM outperformed the other classification algorithms. Using PET and CT information together was shown to be superior to using PET or CT features alone. Research supported by the Prostate

  7. TU-C-12A-12: Differentiating Bone Lesions and Degenerative Joint Disease in NaF PET/CT Scans Using Machine Learning

    Energy Technology Data Exchange (ETDEWEB)

    Perk, T; Bradshaw, T; Muzahir, S; Jeraj, R [University of Wisconsin, Madison, Wisconsin (United States); Meyer, E [Case Western Reserve University School of Medicine, Cleveland, Ohio (United States)

    2014-06-15

    Purpose: [F-18]NaF PET can be used to image bone metastases; however, tracer uptake in degenerative joint disease (DJD) often appears similar to metastases. This study aims to develop and compare different machine learning algorithms to automatically identify regions of [F-18]NaF scans that correspond to DJD. Methods: 10 metastatic prostate cancer patients received whole body [F-18]NaF PET/CT scans prior to treatment. Image segmentation resulted in 852 ROIs, 69 of which were identified by a nuclear medicine physician as DJD. For all ROIs, various PET and CT textural features were computed. ROIs were divided into training and testing sets used to train eight different machine learning classifiers. Classifiers were evaluated based on receiver operating characteristics area under the curve (AUC), sensitivity, specificity, and positive predictive value (PPV). We also assessed the added value of including CT features in addition to PET features for training classifiers. Results: The training set consisted of 37 DJD ROIs with 475 non-DJD ROIs, and the testing set consisted of 32 DJD ROIs with 308 non-DJD ROIs. Of all classifiers, generalized linear models (GLM), decision forests (DF), and support vector machines (SVM) had the best performance. AUCs of GLM (0.929), DF (0.921), and SVM (0.889) were significantly higher than the other models (p<0.001). GLM and DF, overall, had the best sensitivity, specificity, and PPV, and gave a significantly better performance (p<0.01) than all other models. PET/CT GLM classifiers had higher AUC than just PET or just CT. GLMs built using PET/CT information had superior or comparable sensitivities, specificities and PPVs to just PET or just CT. Conclusion: Machine learning algorithms trained with PET/CT features were able to identify some cases of DJD. GLM outperformed the other classification algorithms. Using PET and CT information together was shown to be superior to using PET or CT features alone. Research supported by the Prostate

  8. Children, CT scan and radiation

    Directory of Open Access Journals (Sweden)

    Morteza Bajoghli

    2010-01-01

    Full Text Available Children are more sensitive to radiation than adults. Computer-ized tomography (CT consists of 25 % of all medical imaging. It was estimated that more than 2% of all carcinomas in the USA are due to CT scans. There is an ongoing focus on the reduction of CT scan radiation dose. Awareness about risk-benefits of CT has increased. Reduction of radiological exam is an important issue because the accumulation effects of radiation can be hazardous. In addition, proper protocol should be followed for diagnostic pro-cedures of ionization radiation and computerized tomography. Effective radiation dose should range from 0.8 to 10.5 millisievert. The same protocol should be followed in different hospitals as well. Basic principles of radiation protection should be monitored. As much as possible, both technician and radiologist must be pre-sent during computerized tomography for children, and MRI and ultrasound should be replaced if possible.

  9. CT scanning in patients with amputated legs

    International Nuclear Information System (INIS)

    CT scanning after above-knee amputation and below-knee amputation helps to determine the calcium salt content of the examined bones, and to differentiate changes in the surrounding soft parts. By comaring the sides, it is quite easy to detect osteoporotic changes shortly after amputation which would otherwise remain undetected by X-ray film examination. It is equally easy to verify muscular changes, whereas characteristic changes in density allow to determine the share of vacant fat in muscular atrophy. Initial examinations proved the usefulness of CT diagnosis for early detection of dystrophic osseous and muscular changes and also show the possibilities of early therapy control of dystrophy treatment. (orig.)

  10. Assessment of the risk factors for impending fractures following radiotherapy for long bone metastases using CT scan-based virtual simulation: a retrospective study

    International Nuclear Information System (INIS)

    Radiotherapy for long bone metastases (RTLB) can be complicated by fractures, which considerably increase morbidity and mortality. The aim of this study was to analyze the risk factors for impending fractures following radiotherapy for long bone metastases (RTLB) using CT scan-based virtual simulation. Forty-seven (47) patients were treated with RTLB (18 lung, 11 breast, 10 prostate and 8 other cancers) for a period of 18 months. Two doctors analyzed the CT images prior to radiation therapy. The impending fractures were then monitored and the correlation between bone scan parameters and fracture occurrence was analyzed. The male gender ratio was 0.57 and the mean age 62.8 (33–93) years. The average size of the metastatic lesions was 32 (8–87) x 2 (6–81) x 52 (7–408) mm with cortical involvement (CI) in 66% of cases. The site was in the upper third of the bone in 92% of cases (28 femoral, 17 humeral and two tibial). Ten fractures occurred: two during RTLB, seven after one month and one after 6.6 months. The fractured lesions measured 48 (17–87) x 34 (12–66) x 76 (38–408) mm. The predictive parameters for fracture were osteolytic (39% vs. 10%; p = 0.02) and permeative lesions (42% vs. 0%; p < 0.0005), a Mirels score ≥9 (42% vs. 0%; p < 0.0005), circumferential CI ≥30% (71% vs. 0%, p < 0.00001), CI ≥45 mm in height (67% vs. 0%, p < 0.00001) and CI in thickness =100% (40% vs. 0%; p = 0.0008). In the multivariate analysis, circumferential CI ≥30% was the only predictive parameter for fracture (p = 0.00035; OR = 62; CI 95%: 6.5-595). Overall survival was 91% and 40% at one month and twelve months respectively. Prophylactic primary fixation surgery should always be considered when the circumferential CI ≥30%

  11. 增强扫描CT值在骨巨细胞瘤诊断中的价值%The value of CT contrast enhanced scan value in diagnosis of giant cell tumor of bone

    Institute of Scientific and Technical Information of China (English)

    费强

    2014-01-01

    目的:探讨增强扫描CT值在骨巨细胞瘤诊断中的价值。方法选取26例我院2013年10月~2014年5月治疗的患者为研究对象,对比患者术前增强CT与术后病理,分析增强扫描CT值在骨巨细胞瘤诊断中的价值。结果术后病理证实,共19例患者为骨巨细胞瘤患者。比较骨巨细胞瘤和非骨巨细胞瘤增强扫描CT值,差异有统计学意义。结论骨巨细胞瘤的增强扫描CT值最佳临界值为98HU,增强扫描CT值可作为诊断骨巨细胞瘤的一个参考标准。%Objective To investigate the value of CT contrast enhanced scan value in diagnosis of giant cell tumor of bone. Methods From October 2013 to May 2014,26 patients were as the research objects. Compared preoperative CT contrast enhanced scan and postoperative pathological. Analyzed value of CT contrast enhanced scan value in diagno-sis of giant cell tumor of bone. Results 19 patients were giant cell tumor of bone. Comparative difference of CT con-trast enhanced scan value between Giant cell tumor of bone and non giant cell tumor of bone indicated statistical sig-nificance. Conclusion 98HU is best critical value of CT contrast enhanced scan vatue in giant cell tumor of bone. The CT contrast enhanced scan value can be used as a reference standard in the diagnosis of giant cell tumor of bone.

  12. CT扫描在肿瘤患者SPECT全身骨显像诊断中的增益价值%The added value of CT scanning in diagnosis of SPECT wholebody bone scan imaging for tumor patients

    Institute of Scientific and Technical Information of China (English)

    吴涛

    2015-01-01

    目的:评价同机CT平扫及断层融合显像对全身骨显像中出现的单发、定位不明或难以确诊病灶的诊断价值. 方法:对131例肿瘤患者全身骨显像中出现的单发、定位不明或难以确诊病灶进行同机CT平扫或断层融合显像,由2名高年资核医学医师和1名CT诊断医师双盲阅片,分别计算SPECT、SPECT/CT、SPECT+CT的诊断准确率,并对上述结果进行χ2检验. 结果:对单发、定位不明和难以确诊病灶,SPECT、SPECT/CT、SPECT+CT 对病灶的诊断准确率分别为 69.4%(34/49)、95.8%(23/24)和93.9%(46/49),63.0%(17/27)、100%(23/23)和100%(27/27),76.53%(75/98)、91.9%(34/37)和90.8%(89/98),SPECT/CT和SPECT+CT对病灶的诊断准确率均优于SPECT平面显像,但SPECT/CT和SPECT+CT对不同类型病灶的诊断准确率之间差异均无统计学意义. 结论:SPECT+CT平扫或SPECT/CT明显提高了对肿瘤患者骨显像中不同类型病灶诊断的准确性,具有临床推广应用价值.%Objective:The purpose of this study is to evaluate the value of computed tomography (CT) plain scan or single photon emission computed tomography/computed tomography (SPECT/CT) fusion imaging in diagnosing of single,unclear position and unclear diagnostic lesions showed on wholebody bone scan (WBS) imaging. Methods:According to the study design, SPECT plain scan,CT plain scan or SPECT/CT fusion imaging were performed respectively for single,unclear position and un-clear diagnostic lesions showed on WBS imaging in total 131 tumor patients. The outcomes were reviewed in a double-blind manner by 2 professional nuclear medicine physician and 1 CT physician. A χ2 test was administered statistically to analysis the diagnostic accuracy rates. Results:For single,unclear position and unclear diagnostic lesions,the accuracy rates of SPECT, SPECT/CT and SPECT+CT were 69.4%(34/49),95.8%(23/24) and 93.9%(46/49),63.0%(17/27),100%(23/23) and 100%(27/27), 76.5%(75/98),91.9%(34/37) and 90

  13. Spinal CT scan, 1. Cervical and thoracic spines

    Energy Technology Data Exchange (ETDEWEB)

    Nakagawa, Hiroshi (Aichi Medical Univ. (Japan))

    1982-01-01

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

  14. Bone marrow metastases from alveolar rhabdomyosarcoma with impressive FDG PET/CT finding but less-revealing bone scintigraphy.

    Science.gov (United States)

    Yang, Jigang; Zhen, Lishi; Zhuang, Hongming

    2013-12-01

    An 18F-FDG PET/CT scan was performed in a 26-year-old man with a known alveolar rhabdomyosarcoma for staging. The PET/CT scan showed abnormally increased FDG activity involving almost all bones in the imaged regions. In contrast, 99mTc-MDP whole-body bone scan demonstrated only very limited bone metastases.

  15. CT scanning: patterns of use and dose

    International Nuclear Information System (INIS)

    CT scanning is a relatively high-dose procedure. In spite of the use of magnetic resonance imaging, with faster CT scanners and helical techniques CT is becoming more common. There are few data from practice in the United States regarding the age and sex distribution of patients receiving CT scans, what type of scan and how many scans they receive, or how much radiation dose CT scans contribute. We reviewed over 33 700 consecutive CT examinations done at our institution in 1998 and 1999. Information on the types of scans as well as the age and sex distribution of the patients was determined. Between 1990 and 1999, CT examinations in our institution increased from 6.1% to 11.1% of all radiology procedures. Nineteen per cent of all patients seen in our department in the last year had at least one CT scan and more than half had multiple scans on the same day. Thirty-six per cent of all patients had a prior CT examination done on an earlier date. The male/female ratio of patients was 56/44. Studies of children age 0-15 years comprised 11.2% of scans. The highest percentage of scans was done in the 36-50-year-old age group. CT scanning accounted for 67% of the effective dose from diagnostic radiology. In most large hospitals in the United States CT scanning probably accounts for more than 10% of diagnostic radiology examinations and about two-thirds of the radiation dose. Most patients have multiple scan sequences. Studies done on children are probably more common than previously thought. (author)

  16. Interesting bone scans - unusual findings

    Energy Technology Data Exchange (ETDEWEB)

    Dobson, M.; Wadhwa, S.S.; Mansberg, R.; Fernandes, V.B. [Wollongong Hospital, Wollongong, NSW (Australia)

    1997-12-01

    A 59-year-old female with carcinoma of the colon and known liver metastatic disease was referred for bone scan to evaluate for bone metastases. Although no bone metastases were found, there was abnormal uptake noted in the liver corresponding to a metastatic calcified lesion. The only other findings were of degenerative disease in the cervical spine, right shoulder and small joints of the hands. A 69-year-old male with carcinoma of the prostate and right side low back pain was referred for bone scan. No focal abnormalities to suggest metastatic disease were identified; findings within the cervical spine, lumber spine and knees were presumed secondary to degenerative disease. Intermittent pain persisted and the patient was referred for a repeat bone scan six months later. Previous scan findings of degenerative disease and no metastatic disease were confirmed; however, closer inspection revealed an enlarged right kidney with significant retention of tracer in the pelvicalyceal system suggesting possible obstruction. A Retrograde pyelogram was performed, and no obvious obstruction demonstrated. As bone scan findings were very suggestive of obstruction, a DTPA scan with lasix was performed showing a dilated right collecting system with no functional obstruction. Given the degree of dilation, it is possible that the patient experiences intermittent PUJ obstruction causing his symptoms. A 33-year-old male with insulin dependent diabetes mellitus and viral arthritis was referred for a bone scan. A three phase revealed increased uptake in the region of the knee and leR proximal tibia. Delayed whole body images revealed multiple focal areas of osteoblastic activity in the leR tibia. Abnormal uptake was also seen in the upper third of the leR femur. The remainder of the skeletal survey was normal. X-ray correlation of the leR tibia and femoral findings was undertaken. Combinating unilateral changes on bone scan and X-ray although very suggestive of sclerotic polyostotic

  17. Efficacy of DR, CT and MRI in bone tumors

    Institute of Scientific and Technical Information of China (English)

    Yanjiao Zhang; Xuefeng Cui; Changcheng Li; Shenjiang Li

    2014-01-01

    Objective:The aim of the study was to investigate the ef icacy of digital radiography (DR), computed tomography (CT) and magnetic resonance imaging (MRI) in bone tumors. Methods:Fifty-five patients with histological y confirmed bone tumors underwent imaging examinations. Fifty-five patients were performed DR, 21 CT and 20 MRI. Results:DR of 51 pa-tients clearly revealed bone changes. DR of 40 patients wel showed marginal. Twenty tumors appeared periosteal reaction on DR and 19 calcification on DR. CT scan of 21 patients clearly depicted bone changes, marginal and calcification and CT scan of 8 revealed periosteal reaction. MRI scan of 20 patients al showed marginal and soft-tissue mass and bone marrow edema was prominent in 8 patients. Conclusion:DR is the first imaging approach for born tumors. CT wel reveal the extent and minute structure of the bone tumors, the extent, soft-tissue mass and bone marrow edema are more dramatical y demon-strated on MRI imaging. DR integrates with CT and MRI, is helpful in diagnosis of bone tumors.

  18. The value of enhanced scan CT value in giant cell tumor of bone diagnosis%增强扫描CT在骨巨细胞瘤诊断中的价值

    Institute of Scientific and Technical Information of China (English)

    张中华

    2015-01-01

    Objective:To discuss value of enhanced scan CT value in giant cell tumor of bone diagnosis.Methods:30 patients with giant cell tumor were selected from January 2013 to June 2014,on the enhanced CT scanning,analysis of patients with giant cell tumor of bone enhancement CT scanning function.Resluts:The results of the study showed that the site of the disease in patients with giant cell tumor of bone is mainly distal femur, femoral segment,proximal humerus,tibia segment,distal radius,etc.,giant cell tumor of bone are in level one-level three,CT scan showed that the test results are very complex.Conclusion:For giant cell tumor of bone patients,enhanced CT scan can help the doctor determine the part of the patient's disease as soon as possible, improve patient outcomes,has a certain value and therapeutic advantages,it is worth promoting.%目的:探讨增强扫描CT在骨巨细胞瘤诊断中的临床应用价值。方法:2013年1月-2014年6月收治骨巨细胞瘤患者30例,对其进行增强CT扫描,分析增强CT扫描对骨巨细胞瘤患者的作用。结果:骨巨细胞瘤患者的病发部位主要是股骨下段、股骨上段、肱骨近段、胫骨上段、桡骨远端等,骨巨细胞瘤均处于1~3级之间,增强CT扫描结果显示检测结果非常复杂。结论:对于骨巨细胞瘤患者而言,进行增强CT扫描,有助于主治医生尽快确定患者的病发部位,提高患者的治疗效果,具有一定的应用价值,值得大力推广使用。

  19. CT scan for suspected acute appendicitis

    OpenAIRE

    Widlus, David M.

    2012-01-01

    Appendicitis is common with a 7% lifetime risk for an individual in the United States. Mean age at diagnosis is 22 years old. While frequently clinically obvious, by 2006, more than 90% of patients diagnosed with appendicitis had a CT scan of the abdomen and pelvis performed. Use of CT scans has allowed a decrease in false-negative rate at appendectomy to under 10% from a rate of approximately 20% before routine use of CT scan. In addition, the rate of perforation has decreased from nearly 30...

  20. Bone Scintigraphy and CT Findings in Transverse Process Apophysitis.

    Science.gov (United States)

    Dua, Sumeet G; Ali, Amjad

    2016-07-01

    A 14-year-old avid gymnast presented with recent onset of increasing lower thoracic back pain. Clinical examination revealed point tenderness at about T10 level. Focal uptake was seen to the left of the midline on a bone scan ordered to exclude stress fracture. Spine CT when read in conjunction with the bone scan revealed apophysitis of the transverse process. Apophysitis of the posterior elements of the vertebrae is a rare cause of back pain in adolescents. PMID:26914575

  1. Digital radiographic localization for CT scanning of the larynx

    Energy Technology Data Exchange (ETDEWEB)

    Silverman, P.M.; Korobkin, M.; Rauch, R.F.

    1983-12-01

    Computed tomography (CT) of the larynx is the preferred method for staging laryngeal carcinoma and assessing the extent of injury from trauma. The standard method of examination consists of 5 mm contiguous scans throughout the larynx in quiet respiration. Scans are performed with the patient supine with the neck slightly extended allowing the long axis of the larynx to be perpendicular to the scanning plane. A complete examination requires scanning from the supraglottic region (level of hyoid bone) to the subglottic region (level of cricoid cartlage). In the authors' experience when this method is used, multiple scans are performed cephalad to the level of interest because no upper limit of the examination is established before transaxial scans are done. We have used the lateral digital radiograph of the neck to identify specific landmarks so that the upper and lower limets of the examination can be established before scanning.

  2. Bone Scan "Hot Spot" at the Superior Lateral Orbital Margin Fronto-zygomatic Suture Uptake Characterized with Tc-99m MDP SPECT/CT.

    Science.gov (United States)

    Thang, S P; Tan, A E H; Goh, A S W

    2011-07-01

    Findings of a solitary "hot spot" at the superior lateral orbital margin on bone scan scintigraphy is not uncommonly seen, and is often dismissed as a benign lesion. However, the exact etiology is indeterminate. We present two cases in which hybrid single photon emission computed tomography/computed tomography imaging was able to characterize and localize this uptake, demonstrating correlation to the right fronto-zygomatic suture.

  3. Optical-CT scanning of polymer gels

    International Nuclear Information System (INIS)

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

  4. Evaluation strategies in CT scanning

    DEFF Research Database (Denmark)

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

  5. Growth arrest line mimicking lymphoma involvement: The findings of {sup 99m}Tc-MDP bone SPECT/CT and serial bone scan in a child with non-Hodgkin's lymphoma

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Chan Woo; Kim, Ji Young; Choi, Yun Young; Lee, Seung Hun; Lee, Young Ho [Hanyang University Medical Center, Seoul (Korea, Republic of)

    2016-06-15

    Growth arrest lines appear as dense sclerotic lines parallel to the growth plate of long bones on radiography. We describe the case of a 9-year-old female with growth arrest lines initially masquerading as lymphoma involvement on {sup 99m}Tc-MDP bone scintigraphy who had been treated with chemotherapy for non-Hodgkin's lymphoma about 3 years previously. Subsequent regional bone SPECT/CT clearly diagnosed the growth arrest lines, and retrograde review of previous bone scintigraphy demonstrated line migration in this patient. Growth arrest lines should be considered a possible diagnosis on bone scintigraphy, especially in the surveillance of children who have experienced severe childhood infections, malnutrition, immobilization, or treatment with immunosuppressive or chemotherapeutic drugs that may inhibit bone growth.

  6. Effect of CT scanning on the identification of microstructure of temporal bone of children%CT后重建技术对小儿颞骨细微结构辨别效果

    Institute of Scientific and Technical Information of China (English)

    王忠; 龚苗苗; 洪晓纯; 郭红梅

    2012-01-01

    目的 总结螺旋CT(Spiral computed tomography,SCT)高分辨扫描及后处理技术对小儿颞骨细微结构的辨别.方法 对正常25对耳行螺旋CT检查,归纳和总结重建方法及步骤.结果 采用3项后处理方法均能良好的显示颞骨内的细微结构.结论 64排螺旋CT扫描后3种三维重建技术的应用,能清晰、直观的显示小儿内耳及面神经管的三维结构,为耳鼻喉医生提供准确可靠的影像信息,对临床的诊断和治疗方案的选择具有很高的价值.%Objective To analyze the application of spiral CT (spiral computed tomography,SCT)scanning in indentification the mucirostructure of temporal bone of children. Methods SCThigh resolution scanning wa conducted on 25 normal pairs of children' ears for reconstrcucture. Results SCT high resolution scanning allowed direct observation of the microsctructure of the temporal bone. Conclusion 64-detector MDCT multi-planar is a reliable for clinical diagnosis and treatment of the inner ear.

  7. Contextual Analysis of CT Scanned Pig Carcasses

    DEFF Research Database (Denmark)

    Lyckegaard, Allan; Larsen, Rasmus; Christensen, Lars Bager;

    2006-01-01

    knowledge about the weight of other tissue types from CT. Knowing the weight of individual tissue types will directly give access to other measures such as the weight of the carcass and the Lean Meat Percentage (LMP). Until now, most analyses of CT scans have been based on the Hounsfield spectra that does...... not consider the spatial context in CT scan. Applying contextual methods from the field of image analysis we hope to make a virtual dissection of pig carcasses.......Knowledge of the weight of tissue types in pig carcasses is generally only available after manual dissection. The use of computed tomography (CT) has demonstrated to be a promising approach to gain knowledge on the lean meat weight (Romvari, 2005), but less effort has been put into gaining...

  8. CT scan of bacterial and aseptic meningitis

    Energy Technology Data Exchange (ETDEWEB)

    Takemoto, Kazumasa; Saiwai, Shigeo; Tamaoka, Koichi (Kobe Central Municipal Hospital (Japan))

    1983-01-01

    CT scans of the patients with aseptic and bacterial meningitis were reviewed and compared to previous reports. In aseptic meningitis, no abnormal CT findings were observed. In bacterial meningitis, CT findings were ventricular dilatation, subdural fluid collection, parenchymal low density, intracerebral hematoma and meningeal enhancement after contrast injection. Three patients among 48 suffered from status epileptics during the course of the illness. All of the 3 patients developed parenchymal inhomogeneous low density and progressive ventricular dilatation which did not improve after ventricular peritoneal shunt surgery. We believe that these changes are most likely due to hypoxic hypoxemia during epileptic seizure and meningitis itself seems to play a little role.

  9. The utility of bone scans in rheumatology

    International Nuclear Information System (INIS)

    Full text: Introduction: Bone scans are the commonest diagnostic imaging services requested by Australian rheumatologists. Medicare figures suggest that an average rheumatologist orders about $50 000 (AUS) of bone scans annually. Aims: To ascertain the reasons why rheumatologists request bone scans and how it affects their patient management. Methods: A two-part prospective survey was administered before and after every bone scan ordered by four rheumatologists over a six-month period in 1996. Results: A total of 136 bone scans were requested (66.2% whole body; 33.8% regional; 6% SPECT). The primary indications for scanning were (1) to confirm a clinical diagnosis (38%); (2) to exclude a diagnosis (34%); (3) to localize site of pain (17%); and (4) to assist in management (6%). The common diseases that rheumatologists were attempting to confirm/exclude with bone scanning were inflammatory arthritis, malignancy, and fracture. However, the commonest provisional and final diagnosis was soft tissue rheumatism (18%) followed by inflammatory arthritis (15%) and osteoarthritis (11%). In 24% of patients with a provisional diagnosis of soft tissue rheumatism the diagnosis was changed by the bone scan. The scan was successful in excluding a diagnosis in 88 per cent where this was the primary indication for the test. It was successful in confirming a diagnosis in 79 per cent where this was the primary indication. In 32 per cent the bone scan altered the clinical diagnosis and in 43 per cent it altered management. The bone scan result prevented further investigations in 60 per cent. Conclusions: The commonest pre-scan and post-scan diagnosis is soft tissue rheumatism. Rheumatologists predominantly request bone scanning to confirm or exclude their clinical suspicion of inflammatory arthritis, malignancy, and fracture. Bone scans were successful in achieving these objectives in at least 79 per cent of cases

  10. Reduction of patient radiation dose in Spiral CT scan

    International Nuclear Information System (INIS)

    To optimize patient radiation dose in Spiral CT scan of dento-maxillo-facial region by measuring the absorbed dose in the phantom and to evaluate reliability of dose estimation methods using CTDI (CT Dose Index, FDA, USA). Spiral CT scanning with 'pitchs' (ratio of table speed to slice thickness per rotation) more than 1 was used for dose measurements. The dose was measured using a human phantom (Alderson Research Laboratories, USA) in the CT scan with a 3rd generation CT scanner of Somatom Plus (Siemens, Germany) for bone imaging. CTDI for this CT scanner were 9.2 mGy/100 mA at the center in an acrylic resin phantom with diameter of 16 cm and 8.5 mGy/100 mA at 1 cm depth from the phantom surface. X-ray tube voltage of 120 kV and tube current of 85 mA was used. Slice thickness was varied from 1 to 3 mm and table speed per rotation was also varied from 1 to 5 mm per rotation. X-Omat-V (Eastman Kodak, USA) films and TLD (Thermo-Luminescent-Dosimetry) dosimeters of the type of MSO-S (Kyokko, Japan) were used in the dosimetry. Patients radiation dose reduced with increasing the pitch of SPIRAL scan. Measured dose was uniformly distributed and well corresponded to the dose calculated using CTDI. However, measured doses on scanning with 1 mm slice thickness were always higher than those with 2 to 5 mm slice thickness. The lowest radiation dose was obtained with scanning with 2 mm slice thickness and table speed of 4 mm per rotation which give the dose of about 4 mGy per one CT examination in the imaged tissues. The highest dose per one CT examination was measured in 'dental CT' for the mandibular region with 1 mm slice thickness and table speed of 1 mm per rotation which gave 12 mGy by film dosimetry and 9 mGy by TLD dosimetry. SPIRAL scan with pitch more than 1 was effective for reduction of patient radiation dose without reducing the image quality. CTDI was also useful to estimate the dose except scans with 1 mm slice thickness. (author)

  11. Use of Gamma Correction Pinhole Bone Scans in Trauma

    Energy Technology Data Exchange (ETDEWEB)

    Bahk, Youg Whee [Sung Ae Hospital, Seoul (Korea, Republic of); Chung, Youg An; Park, Jung Mee [Catholic Univ. of Korea, Seoul (Korea, Republic of)

    2012-03-15

    {sup 99}mTc hydroxydiphosphonate (HDP) bone scanning is a classic metabolic nuclear imaging method and the most frequently performed examination. Clinically, it has long been cherished as an indispensable diagnostic screening tool and for monitoring of patients with bone, joint, and soft tissue diseases. The HDP bone scan, the pinhole scan in particular, is known for its ability to detect increased, decreased, or defective tracer uptake along with magnified anatomy. Unfortunately, however, the findings of such uptake changes are not specific in many traumatic bone disorders, especially when lesions are minute and complex. This study discusses the recently introduced gamma correction pinhole bone scan (GCPBS), emphasizing its usefulness in the diagnosis of traumatic bone diseases including occult fractures; and fish vertebra. Indeed, GCPBS can remarkably enhance the diagnostic feasibility of HDP pinhole bone scans by refining the topography, pathologic anatomy, and altered chemical profile of the traumatic diseases in question. The fine and precise depiction of anatomic and metabolic changes in these diseases has been shown to be unique to GCPBS, and they are not appreciated on conventional radiographs, multiple detector CT, or ultrasonographs. It is true that MR imaging can portray proton change, but understandably, it is a manifestation that is common to any bone disease.

  12. Bone scanning in severe external otitis

    Energy Technology Data Exchange (ETDEWEB)

    Levin, W.J.; Shary, J.H. 3d.; Nichols, L.T.; Lucente, F.E.

    1986-11-01

    Technetium99 Methylene Diphosphate bone scanning has been considered an early valuable tool to diagnose necrotizing progressive malignant external otitis. However, to our knowledge, no formal studies have actually compared bone scans of otherwise young, healthy patients with severe external otitis to scans of patients with clinical presentation of malignant external otitis. Twelve patients with only severe external otitis were studied with Technetium99 Diphosphate and were compared to known cases of malignant otitis. All scans were evaluated by two neuroradiologists with no prior knowledge of the clinical status of the patients. Nine of the 12 patients had positive bone scans with many scans resembling those reported with malignant external otitis. Interestingly, there was no consistent correlation between the severity of clinical presentation and the amount of Technetium uptake. These findings suggest that a positive bone scan alone should not be interpreted as indicative of malignant external otitis.

  13. Bone scan in diagnosis of infectious osteoarthritis

    International Nuclear Information System (INIS)

    Bone scan with Technetium 99m is harmless method of evaluation of skeletal lesions. It is safe in pediatrics age group and it can be used in early diagnosis of infectious osteoarthritis. Bone scan differentiate osteomyelitis from cellulitis, and also it may help in diagnosis of subclinical involvement of rheumatoid arthritis, benign and malignant bone tumors, stress fractures and periostitis. We report results of bone scan in 30 pediatrics patients as follow: osteomyelitis 9 cases, cellulitis 4 cases, infectious arthritis 7 cases, tuberculous osteoarthritis 2 cases, rheumatoid arthritis 2 cases, and other different diseases 9 cases

  14. Bone scan in diagnosis of infectious osteoarthritis

    International Nuclear Information System (INIS)

    Bone scan with Technetium 99m is harmless method of evaluation of skeletal lesions. It is safe in pediatrics age group and it can be used in early diagnosis of infectious osteo-arthritis. Bone scan differentiate osteomyelitis from cellulitis, and also it may help in diagnosis of subclinical involvement of rheumatoid arthritis, benign and malignant bone tumors, stress fractures and periostitis. We report results of bone scan in 30 pediatric patients as follows: osteomyelitis 9 cases, cellulitis 4 cases, infectious arthritis 4 cases, tuberculous osteoarthritis 2 cases, rheumatoid arthritis 2 cases and other different diseases 9 cases

  15. Does low-field dedicated extremity MRI (E-MRI) reliably detect bone erosions in rheumatoid arthritis? A comparison of two different E-MRI units and conventional radiography with high-resolution CT scanning

    DEFF Research Database (Denmark)

    Duer-Jensen, A; Ejbjerg, B; Albrecht-Beste, E;

    2008-01-01

    . RESULTS: 550 bones were examined. CT, Artoscan, MagneVu and CR detected 188, 116, 55 and 45 bones with erosions, respectively. The majority were located in the carpal bones. The sensitivity of the Artoscan for detecting erosions was higher than that of the MagneVu and CR (MCP joints: 0.68, 0.54 and 0...

  16. Appearing and disappearing CT scan abnormalities and seizures.

    OpenAIRE

    P K Sethi; Kumar, B.R.; Madan, V S; Mohan, V

    1985-01-01

    A group of patients presenting with seizures (focal or generalised) and abnormal CT scans who, on follow up, showed complete resolution of the CT scan changes, without any treatment other than anticonvulsants, are described.

  17. Gout: Value of bone scanning

    Energy Technology Data Exchange (ETDEWEB)

    Oliva, J.P.; Cardenas, R.; Bell, L.; Gonzalez Griego, J.

    1986-12-01

    11 male patients with gout were studied by means of bone scintigraphy with /sup 99m/TcMDP. This diagnostic method rendered possible the diagnosis of clinically or roentgenologically occult bone involvement. Bone scintigraphy may be useful procedure to monitor therapy of gout.

  18. Physical performance characteristics of spiral CT scanning

    International Nuclear Information System (INIS)

    This paper reports on CT scanning in spiral geometry that has recently been introduced; it is achieved by continuous patient transport during continuous multirotational data acquisition. While the advantages for clinical studies are obvious, the physical performance characteristics have to be investigated to detail. Phantom studies and clinical studies have been performed on a Somatom Plus (Siemens AG, Erlangen, West Germany). In addition, simulation studies have been carried out to estimate section-sensitivity profiles, noise, and artifact behavior. RESULTS: Many of the standard physical performance characteristics (eg, spatial resolution, image uniformity, dose values, and contrast) are not affected by spiral CT scanning. Artifact behavior, pixel noise, and section-sensitivity profiles are changed as a function of table speed; the changes agree with predictions by simulation. Pixel noise is reduced by about a factor of 0.8 in reconstruction by an interpolation procedure. Sensitivity profiles are smoothed because the original profile is convolved with the object motion function. Drawbacks of spiral CT with respect to image quality are not significant. The advantages offered by continuous canning and arbitrary retrospective selection of section positions within the scanned volume clearly more than compensate for the slight disadvantages

  19. Optimising doses in paediatric CT scanning

    International Nuclear Information System (INIS)

    Computed tomography is still extensively used in paediatric imaging. This technique remains a benchmark for bone, lung, cardiovascular exploration and for emergency imaging. The multi-slice technique has revolutionized image quality by improving spatial resolution and bringing acquisition times down to a few seconds, thus almost totally eliminating the problem of movement artefacts common with children. This technique will not therefore be abandoned any time in the near future by paediatric radiologists. However, these multi-slice CT devices today allow rapid and repetitive exploration of large volumes, which can lead to significant individual exposure [1]. A number of surveys have shown that the exposure parameters used in paediatrics are too high when compared with adult protocols [2, 3] even though a lesser dose can provide equivalent image quality [4]. These paediatric CT optimisation measures are currently the subject of an extensive campaign in the literature [5-7]. (author)

  20. SPECT-CT bone scintigraphy in cancer patients

    International Nuclear Information System (INIS)

    Full text: Introduction: SPECT-CT study allows the precise correlation between functional and morphological data on the same image. Methods: Whole body bone scan (WBBS) is a diagnostic modality still firmly established as a valuable tool to assess skeleton abnormalities. CT is an imaging method for characterizing destruction of the bone spongy lesions, their consolidation or calcium accumulation. This fact allows differentiation of the osteolytic metastases from the osteosclerotic and mixed lesions and also from degenerative ones. Whole body bone scan followed by SPECT-CT scanning increases the accuracy of the study and potentially accelerates the diagnosis of the patient based on a single imaging session. This is especially important in cancer patients. Results and discussion: After retrospectively review of WBBS and SPECT-CT fused images 141 bone lesions in 89 pts were analyzed The skeletal findings with previously uncertain character were classified as definitely benign, indeterminate or definitely malignant. 1. 47 (33%) of all lesions in 36 pts could be correlated with benign degenerative findings on SPECT-CT images. 5 (3%) lesions in 3 of these pts were indeterminate on the SPECT-CT images. They were localized in the area of articulation parts and corpus of the thoracic vertebra and ribs. After additional MRT examination and 6 months follow-up these changes were considered degenerative: osteopathy changes and presence of spondyloarthrosis and osteochondrosis; compression fractures due to advanced osteoporosis. These pts were with prolonged chormono/chemotherapy; chronic inflammatory disease of the coxofemoral articulation, coxarthrosis, aseptic necrosis of the femoral head and postoperative sacroiliitis; post-traumatic fractures or surgical intervention; hyperplastic degenerative lesions in the skeleton and asymmetrical pelvic bone structures due to M. Paget. 2. 41 (28,1%) single osseous metastatic spots (up to 3 foci) were scanned in 31 pts. 3. 13 (10

  1. Depiction of Nidi and Fibrovascular Zones of Osteoid Ostemas Using Gamma Correction Tc 99m HDP Pinhole Bone Scan and Conventional Radiograph, and Correlation with CT, MRI, and PVC Phantom Imaging

    Energy Technology Data Exchange (ETDEWEB)

    Bahk, Youg Whee [Sung Ae Hospital, Seoul (Korea, Republic of); Kim, Sung Hoon; Chung, Yong An; Bahk, Won Jong; Park, Jung Mee; Kang, You Mee; Choi, Woo Hee; Park, Young Ha; Sohn, Hyung Sun; Kim, Byung Ki; Chung, Soo Kyo [The Catholic Univ. of Korea, Seoul (Korea, Republic of)

    2011-03-15

    For the precise imaging diagnosis of osteoid osteoma (OO), the identification of the nidus and fibrovascular zone (FVZ) is essential. However, the latter sign has received little attention because it is difficult to demonstrate. We applied the recently introduced gamma correction (GC) to depict the FVZ on pinhole bone scan (PBS), conventional radiography (CR), and computed tomography (CT). Non gamma correction MRI was also analyzed for reference. Ten patients with histologically proven diagnoses of OO were enrolled in this retrospective study. PBS, CR, and CT were processed by GC to demonstrate the nidi and FVZ as distinct yet integrating components of OO. PBS was performed using a 4mm pinhole collimator 3 h after iv injection of 925 to 1, 110 MBq (25 to 30mCi) of Tc 99m HDP, and anteroposterior and mediolateral CR and transverse CT were taken according to the standard technique. MRI sequences included T1 and T2 weighted images. For gamma correction, we utilized the Photo Correction Wizard program of ACD Photo Editor v3. 1. A team of three qualified nuclear physician radiologists, two nuclear physicians, and one MRI specialist read bone scans, radiographs, and MRIs of OO according to each specialty, and orthopaedic aspects and histology were reviewed by one qualified orthopedic surgeon and two qualified pathologists, respectively. Each observer first read the images separately with basic information about the aim of the study given and then in concert. Interpretive disagreement was settled by discussion and consensus. On pinhole scan, nidi were presented as areas of intense tracer uptake in all cases, and, importantly after GC, a thin ring like zone with lower tracer uptake became visible in seven out of ten cases. GCCR also revealed a thin lucent zone that circumscribed the nidi in six out of ten cases and GCCT in two of four cases. MRI, without GC, presented nidi with high signal in the center and a thin ring like zone with low signal in the periphery in five out

  2. Topographic diagnosis of parathyroid tumor by CT scan

    Energy Technology Data Exchange (ETDEWEB)

    Fukunaga, M.; Harioka, T.; Morita, R. (Kyoto Univ. (Japan). Faculty of Medicine)

    1981-10-01

    In order to detect the hyperfunctioning parathyroid gland(s), CT scan over the neck was performed in patients with parathyroid disorders, including 10 primary hyperparathyroidism (6 bone type, 3 stone type and 1 chemical type), 8 chronic renal failure on hemodialysis with renal osteodystrophy and 2 multiple endocrine adenomatosis (MEA) type I. We used a whole-body scanner (CT/T, GE). The slice thickness was 5 mm. All patients were scanned from the sternal notch upward to the larynx, and were enhanced by the administration of 30% DIP Conray for 15 min. The results of the topographic diagnosis were compared with the surgical findings. Precise preoperative localization was accomplished in 9/10 adenomas in primary hyperparathyroidism, 27/32 hyperplasias in secondary hyperparathyroidism, and 2/4 hyperplasias in MEA type I. The smallest lesion weighed 0.2 g. It was shown that CT scan over the neck was a noninvasive and simple method to define the localization of hyperfunctionig parathyroid gland(s).

  3. 99mTc-MDP bone scan combined with CT in the clinical value of breast cancer%99mTc-MDP骨显像联合CT在乳腺癌术后的临床价值

    Institute of Scientific and Technical Information of China (English)

    黄晓红; 智生芳; 蒋宁一

    2010-01-01

    Objective To evaluate the value of clinical application of the combination of CT and 99mTc-MDP bone scan in the follow-up monitoring of cancer recurrences of the breast cancer patients previously treated with both mastecomy and chemotherapy Methods 253 female breast cancer patients treated with mastectomy and chemotherapy within the past one year were enrolled in this study. All of them underwent CT,99mTc-MDP bone scan. calculation of the sensitivity, specialty, accuracy, were analyzed. Results There were 122 patients had the bone metastasis in 253 patients diagnosed breast cancer. the incidence rate was 48.2% . The thoracic part had the most incident of osseous metastasis(50.9%) ,then the vertebral body(41.8%) ,pelvis(25.4%),limbs bone (14. 5 %), skull and the other parts(9. 1%). The sensitivity, specialty, accuracy of 99mTc-MDP bone scan in determining osseuous metastasis were 93.2% 、90. 7% 、91.3% respectively;The sensitivity, specialty,accuracy of CT in the detection of cancer recurrence were 58. 2% 、87.8% 、73.5% respectively in CT scan.When combining 99mTc-MDP bone scan with CT scan,they were 93.4% 、91.6% 、92.5% respectively. Conclusion The incidence rate of osseous metastasis is very high for the breast cancer patients, and the incidence of the osseous metastasis has definite rules and features. the combination of CT and 99mTc-MDP in the follow-up studies of the breast cancer patients previously treated with both mastectomy and chemotherapy can obtain the higher sensitivity, specialty and accuracy, making a significant contribution to the value of clinical application.%目的 探讨99mTc-MDP骨显像联合CT在乳腺癌术后早期随访中,检测其复发及转移临床价值.方法 对253例术后病理确诊的乳腺癌患者一年后分别进行99mTc-MDP骨显像、CT扫描,计算灵敏度、特异性、准确性以及分析骨转移的特点.结果 253例乳腺癌全身骨显像中,发现复发或转移者122例,发生率为48.2%,99mTc-MDP发

  4. Role of bone scan in rheumatic disease

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Yun Young [Hanyang University College of Medicine, Seoul (Korea, Republic of)

    2003-06-01

    Rheumatic diseases can be categorized by pathology into several specific types of musculoskeletal problems, including synovitis (e.g. rheumatoid arthritis), enthesopathy (e.g. ankylosing spondylitis) and cartilage degeneration (e.g. osteoarthritis). Skeletal radiographs have contributed to the diagnosis of these articular diseases, and some disease entities need typical radiographic changes as a factor of the diagnostic criteria. However, they sometimes show normal radiographic findings in the early stage of disease, when there is demineralization of less than 30-50%. Bone scans have also been used in arthritis, but not widely because the findings are nonspecific and it is thought that bone scans do not add significant information to routine radiography. Bone scans do however play a different role than simple radiography, and it is a complementary imaging method in the course of management of arthritis. The image quality of bone scans can be improved by obtaining regional views and images under al pin-hole collimator, and through a variety of scintigraphic techniques including the three phase bone scan and bone SPECT. Therefore, bone scans could improve the diagnostic value, and answer multiple clinical questions, based on the pathophysiology of various forms of arthritis.

  5. Bone scans in nasopharyngeal carcinoma: local experience

    International Nuclear Information System (INIS)

    Introduction: Nasopharyngeal carcinoma (NPC) tops the list of malignancy in Malaysia and ranks first in male malignancy in the state of Sarawak. The majority of the NPC patients presented in the advanced stages and often with distal metastasis usually to the bones. In our local hospital is the new practice of bone scan using Tc99 started last year. Over a period of 9 months from July 2003 to March 2004, 41 NPC patients had the bone scans and our experience in these are reviewed and presented. Method: The NPC patients are selected consecutively including both new and treated patients. The scanner used is Siemen E.cam plus and Technecium (Tc99) the radio-active isotope used. The scan images are read and reported by qualified and trained Radiologists. The bone scans are requested from the ENT Specialist of the ENT department of the Hospital. The bone scan reports are checked by the ENT Specialists and the decisions made as to clinical correlation and further definitive imaging studies. Results: 41 NPC patients were included in the studies, 29 newly diagnosed and bone-canned before treatment started and 12 treated of which 3 being diagnosed having recurrent NPC. Of the 29 newly diagnosed patients, one was found true positive bone scan having increased radio-tracer uptake and confirmed Xray imagings. 3 of the treated patients had true positive bone scan with increased radio-tracer uptake and confirmed Xray imagings. Hence a total of 4 out of the 41 patients (9.8%) had bone metastasis on positive bone scans. Of the 29 newly diagnosed patients, 14 were found false positive bone scan having increased radio-tracer uptake but no confirmed X ray imagings. 4 of the treated patients had false positive bone scan with increased radio-tracer uptake but no confirmed X ray imagings. Hence a total of 18 out of the 41 patients (44%) had no bone metastasis on positive bone scans. There were 6 patients with symptoms referable to the bones' distal to the head and 2 had true positive bone

  6. Complications in CT-guided Procedures: Do We Really Need Postinterventional CT Control Scans?

    Energy Technology Data Exchange (ETDEWEB)

    Nattenmüller, Johanna, E-mail: johanna.nattenmueller@med.uni-heidelberg.de; Filsinger, Matthias, E-mail: Matthias_filsinger@web.de; Bryant, Mark, E-mail: mark.bryant@med.uni-heidelberg.de; Stiller, Wolfram, E-mail: Wolfram.Stiller@med.uni-heidelberg.de; Radeleff, Boris, E-mail: boris.radeleff@med.uni-heidelberg.de; Grenacher, Lars, E-mail: lars.grenacher@med.uni-heidelberg.de; Kauczor, Hans-Ullrich, E-mail: hu.kauczor@med.uni-heidelberg.de; Hosch, Waldemar, E-mail: waldemar.hosch@urz.uni-heidelberg.de [University Hospital Heidelberg, Department of Diagnostic and Interventional Radiology (Germany)

    2013-06-19

    PurposeThe aim of this study is twofold: to determine the complication rate in computed tomography (CT)-guided biopsies and drainages, and to evaluate the value of postinterventional CT control scans.MethodsRetrospective analysis of 1,067 CT-guided diagnostic biopsies (n = 476) and therapeutic drainages (n = 591) in thoracic (n = 37), abdominal (n = 866), and musculoskeletal (ms) (n = 164) locations. Severity of any complication was categorized as minor or major. To assess the need for postinterventional CT control scans, it was determined whether complications were detected clinically, on peri-procedural scans or on postinterventional scans only.ResultsThe complication rate was 2.5 % in all procedures (n = 27), 4.4 % in diagnostic punctures, and 1.0 % in drainages; 13.5 % in thoracic, 2.0 % in abdominal, and 3.0 % in musculoskeletal procedures. There was only 1 major complication (0.1 %). Pneumothorax (n = 14) was most frequent, followed by bleeding (n = 9), paresthesia (n = 2), material damage (n = 1), and bone fissure (n = 1). Postinterventional control acquisitions were performed in 65.7 % (701 of 1,067). Six complications were solely detectable in postinterventional control acquisitions (3 retroperitoneal bleeds, 3 pneumothoraces); all other complications were clinically detectable (n = 4) and/or visible in peri-interventional controls (n = 21).ConclusionComplications in CT-guided interventions are rare. Of these, thoracic interventions had the highest rate, while pneumothoraces and bleeding were most frequent. Most complications can be detected clinically or peri-interventionally. To reduce the radiation dose, postinterventional CT controls should not be performed routinely and should be restricted to complicated or retroperitoneal interventions only.

  7. Prediction of trabecular bone qualitative properties using scanning quantitative ultrasound

    Science.gov (United States)

    Qin, Yi-Xian; Lin, Wei; Mittra, Erik; Xia, Yi; Cheng, Jiqi; Judex, Stefan; Rubin, Clint; Müller, Ralph

    2013-11-01

    Microgravity induced bone loss represents a critical health problem in astronauts, particularly occurred in weight-supporting skeleton, which leads to osteopenia and increase of fracture risk. Lack of suitable evaluation modality makes it difficult for monitoring skeletal status in long term space mission and increases potential risk of complication. Such disuse osteopenia and osteoporosis compromise trabecular bone density, and architectural and mechanical properties. While X-ray based imaging would not be practical in space, quantitative ultrasound may provide advantages to characterize bone density and strength through wave propagation in complex trabecular structure. This study used a scanning confocal acoustic diagnostic and navigation system (SCAN) to evaluate trabecular bone quality in 60 cubic trabecular samples harvested from adult sheep. Ultrasound image based SCAN measurements in structural and strength properties were validated by μCT and compressive mechanical testing. This result indicated a moderately strong negative correlations observed between broadband ultrasonic attenuation (BUA) and μCT-determined bone volume fraction (BV/TV, R2=0.53). Strong correlations were observed between ultrasound velocity (UV) and bone's mechanical strength and structural parameters, i.e., bulk Young's modulus (R2=0.67) and BV/TV (R2=0.85). The predictions for bone density and mechanical strength were significantly improved by using a linear combination of both BUA and UV, yielding R2=0.92 for BV/TV and R2=0.71 for bulk Young's modulus. These results imply that quantitative ultrasound can characterize trabecular structural and mechanical properties through measurements of particular ultrasound parameters, and potentially provide an excellent estimation for bone's structural integrity.

  8. Bone scan in inflammatory osseous disease

    International Nuclear Information System (INIS)

    The /sup 99m/Tc-phosphate bone scan has become a sensitive, reliable, and safe method for evaluating the patient with suspected inflammatory disease of bone. The scan may become positive as early as the first 24 hr after the symptoms and 10-14 days before roentgenographic changes occur. It can be used to differentiate successfully a variety of diseases from osteomyelitis, and in conjunction with 67Ga-citrate scan has become a mainstay in the work-up of the patient with infectious disease. Applications of the bone scan to infectious diseases in pediatric practice are especially helpful, since these diseases are common problems in this age group. Increased experience with the /sup 99m/Tc-phosphate bone scan has already defined several areas of ''limitations'' in evaluating inflammatory disease. ''Cold'' defects, negative scans in early stages of osteomyelitis, and ''extended uptake'' may all pose problems in interpretation, but careful correlation of the bone scan results with clinical history and physical findings, blood cultures, and roentgenography will significantly reduce these problems

  9. Bariatric diagnostic CT scanning: A radiotherapy perspective

    International Nuclear Information System (INIS)

    Obesity is increasing in the United Kingdom. Equipment available for this patient group including wheelchairs, beds and hoists is becoming more common in the hospital environment; diagnostic imaging equipment that can accommodate bariatric patients has not increased at the same rate. Subsequently these service-users are often unable to receive “gold-standard” cross-sectional imaging within their patient-pathway. This paper highlights how a diagnostic imaging department has utilised wide-bore CT scanning equipment within the radiotherapy setting to ensure an equitable service for all service users. Through literature review and local experience, a standard operating procedure and scanning service has been developed. Areas explored include technical consideration of scanner design; patient positioning; image artefacts and intravenous contrast administration. Also investigated is patient wellbeing incorporating manual handling, respiration and psycho-social needs. Additionally, demonstration of how interprofessional collaboration by diagnostic and radiotherapy radiographers can ensure the best imaging experience and outcome for this patient group. - Highlights: • Rising obesity in the UK has highlighted a shortage of diagnostic imaging facilities. • Large bore CT scanners are the scanner of choice for radiotherapy planning. • Technical capability, manual handling and psycho-social issues have been explored. • Bariatric diagnostic imaging facilitated by inter-professional collaboration

  10. The role of 18F–NaF PET/CT in metastatic bone disease

    Directory of Open Access Journals (Sweden)

    Mine Araz

    2015-09-01

    Conclusion: Although further prospective clinical studies in specific cancer populations are indicated to set the place of 18F–NaF PET/CT in diagnostic scheme, the results of this pilot study from our country support the superiority of 18F–NaF PET/CT in investigation of bone metastasis over 99mTc-MDP bone scan and 18F-FDG PET/CT in various malignancies. 18F–NaF PET/CT is coming forward as a single step bone seeking study, considering all the advantages, but especially potential of detecting occult metastases and reliably directing patient management.

  11. FEATURE EXTRACTION OF BONES AND SKIN BASED ON ULTRASONIC SCANNING

    Institute of Scientific and Technical Information of China (English)

    Zheng Shuxian; Zhao Wanhua; Lu Bingheng; Zhao Zhao

    2005-01-01

    In the prosthetic socket design, aimed at the high cost and radiation deficiency caused by CT scanning which is a routine technique to obtain the cross-sectional image of the residual limb, a new ultrasonic scanning method is developed to acquire the bones and skin contours of the residual limb. Using a pig fore-leg as the scanning object, an overlapping algorithm is designed to reconstruct the 2D cross-sectional image, the contours of the bone and skin are extracted using edge detection algorithm and the 3D model of the pig fore-leg is reconstructed by using reverse engineering technology. The results of checking the accuracy of the image by scanning a cylinder work pieces show that the extracted contours of the cylinder are quite close to the standard circumference. So it is feasible to get the contours of bones and skin by ultrasonic scanning. The ultrasonic scanning system featuring no radiation and low cost is a kind of new means of cross section scanning for medical images.

  12. Monte Carlo simulation of red bone marrow dose from CT examination

    International Nuclear Information System (INIS)

    To evaluate the methods of calculating red bone marrow dose from CT scan, simulating red bone marrow do ses from different CT scan protocols using different energy can provide the basic dose data for patient radiation protection. Method: Monte Carlo software MCNPX and RPI voxel phantom were used for the simulation, by mass absorption coefficient (MEAC) method, energy including 80 kV, 100 kV, 120 kV and 140 kV of the CT device were simulated, and different CT protocols such as chest scan, abdomen scan and body scan were taken into consideration when simulating the red bone marrow dose (mGy/100 mAs). Results: Under the same other conditions, the larger beam energy caused larger red bone marrow dose, the results of 140 kV was two times larger than that of 80 kV for the same protocol; while under the same beam energy, the difference among different protocol was less than 10%. Conclusion: Under the same conditions, the red bone marrow dose from CT scan depends on beam energy (tube voltage) and total effective mAs; if the total effective mAs was constant, the influence of scan protocol to red bone marrow dose was not much. (authors)

  13. Full-Body CT Scans - What You Need to Know

    Science.gov (United States)

    ... Compared to most other diagnostic X-ray procedures, CT scans result in relatively high radiation exposure. The risks associated with such exposure are greatly outweighed by the benefits of diagnostic and therapeutic CT. However, for whole- ...

  14. Use of Bone Scan During Initial Prostate Cancer Workup, Downstream Procedures, and Associated Medicare Costs

    Energy Technology Data Exchange (ETDEWEB)

    Falchook, Aaron D. [Department of Radiation Oncology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina (United States); Salloum, Ramzi G. [Department of Health Services Policy and Management, University of South Carolina, Columbia, South Carolina (United States); Hendrix, Laura H. [Department of Radiation Oncology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina (United States); Chen, Ronald C., E-mail: ronald_chen@med.unc.edu [Department of Radiation Oncology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina (United States); Cecil G. Sheps Center for Health Services Research, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina (United States); Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina (United States)

    2014-06-01

    Purpose: For patients with a high likelihood of having metastatic disease (high-risk prostate cancer), bone scan is the standard, guideline-recommended test to look for bony metastasis. We quantified the use of bone scans and downstream procedures, along with associated costs, in patients with high-risk prostate cancer, and their use in low- and intermediate-risk patients for whom these tests are not recommended. Methods and Materials: Patients in the Surveillance, Epidemiology, and End Results (SEER)-Medicare database diagnosed with prostate cancer from 2004 to 2007 were included. Prostate specific antigen (PSA), Gleason score, and clinical T stage were used to define D'Amico risk categories. We report use of bone scans from the date of diagnosis to the earlier of treatment or 6 months. In patients who underwent bone scans, we report use of bone-specific x-ray, computed tomography (CT), and magnetic resonance imaging (MRI) scans, and bone biopsy within 3 months after bone scan. Costs were estimated using 2012 Medicare reimbursement rates. Results: In all, 31% and 48% of patients with apparent low- and intermediate-risk prostate cancer underwent a bone scan; of these patients, 21% underwent subsequent x-rays, 7% CT, and 3% MRI scans. Bone biopsies were uncommon. Overall, <1% of low- and intermediate-risk patients were found to have metastatic disease. The annual estimated Medicare cost for bone scans and downstream procedures was $11,300,000 for low- and intermediate-risk patients. For patients with apparent high-risk disease, only 62% received a bone scan, of whom 14% were found to have metastasis. Conclusions: There is overuse of bone scans in patients with low- and intermediate-risk prostate cancers, which is unlikely to yield clinically actionable information and results in a potential Medicare waste. However, there is underuse of bone scans in high-risk patients for whom metastasis is likely.

  15. High resolution CT of temporal bone trauma

    Energy Technology Data Exchange (ETDEWEB)

    Youn, Eun Kyung [Korea General Hospital, Seoul (Korea, Republic of)

    1986-10-15

    Radiographic studies of the temporal bone following head trauma are indicated when there is cerebrospinal fluid otorrhea or rhinorrhoea, hearing loss, or facial nerve paralysis. Plain radiography displays only 17-30% of temporal bone fractures and pluridirectional tomography is both difficult to perform, particularly in the acutely ill patient, and less satisfactory for the demonstration of fine fractures. Consequently, high resolution CT is the imaging method of choice for the investigation of suspected temporal bone trauma and allows special resolution of fine bony detail comparable to that attainable by conventional tomography. Eight cases of temporal bone trauma examined at Korea General Hospital April 1985 through May 1986. The results were as follows: Seven patients (87%) suffered longitudinal fractures. In 6 patients who had purely conductive hearing loss, CT revealed various ossicular chain abnormality. In one patient who had neuro sensory hearing loss, CT demonstrated intract ossicular with a fracture nearing lateral wall of the lateral semicircular canal. In one patient who had mixed hearing loss, CT showed complex fracture.

  16. A case of multiple mycotic aneurysms demonstrated by CT scan

    International Nuclear Information System (INIS)

    A case of multiple mycotic aneurysms demonstrated by CT scan and cerebral angiography was reported. A 59-year-old female was admitted to our hospital with complaints of a dull headache and the left upper, lower, and right upper limb paresis. Lumbar puncture neglected SAH attack. CT scan showed many high-density spots. Followed cerebral angiogram revealed aneurysm-like deposits at the periphery of left MCA, PCA, and the periphery of right PCA. It appeared obvious that those were multiple mycotic aneurysms demonstrated by CT scan. By the reason that those were multiple and may be unruptured we chose conservative therapy. Sequential CT scan and angiography showed no change during 10 months. The conclusions are as follows: 1) mycotic aneurysm may be better shown by enhancement CT scan than an usual aneurysm as their morphorogical characteristic, and 2) catastrophic fetal SAH will be prevented or be prospective by sequential CT scan (in patients with the clinical features). (author)

  17. Three phase bone scan in sports injuries

    International Nuclear Information System (INIS)

    Full text: Sports injuries are common in individual who participate in sports and exercise related activities. In majority of sports related injuries such as stress fracture, periosteitits, acute stress reaction of bone, the radiological investigations are usually normal in early stages. These injuries can lead to serious complications if not detected early and managed properly. This study was jointly carried out in premier medical institutes. All patients were referred from premier sports institute of the country and also by orthopedic surgeons. All patients were subjected for relevant radiological investigations and 3 phase bone scan. Total number of cases included in this study was 70 (N=70) among which bone scan was positive for stress fracture in 45 patients and shin splint was detected in 15 patients and avulsion injury seen in 3 patients. However, only one patient showed features of avulsion injury in X ray and in 1 patient X-ray was inconclusive. Conclusion:-The study shows that 3 phase bone scan is the most sensitive and relatively an inexpensive study. Bone scan has the ability for early detection of sports injuries and provide physiological information and evaluate multiple sites in single examination.SPECT study will help in the diagnostic specificity. (author)

  18. Bone scanning in Shin Splint evaluation

    International Nuclear Information System (INIS)

    Jogging is increasingly popular; in U.S.A., in 1979 more than 25 millions people were considered joggers. Lesions of the locomotive system of the lower limbs are very frequent in athletes and the Shin Splint syndrome, for one, is very frequent. However this precise clinical entity, usually X-Ray negative, is ill-known. A bone scan study in a series of 30 athletes suffering from Shin Splints is presented. The bone scans being positive and typical were highly useful in confirming the clinical diagnosis. Moreover, follow-up studies were done in a number of these patients and results correlated well with the clinical evolution

  19. An anatomically shaped lower body model for CT scanning of cadaver femurs

    Energy Technology Data Exchange (ETDEWEB)

    Tanck, Esther; Deenen, J C W; Verdonschot, Nico [Orthopaedic Research Laboratory, Radboud University Nijmegen Medical Center, PO Box 9101, 6500 HB Nijmegen (Netherlands); Huisman, Henk Jan [Department of Radiology, Radboud University Nijmegen Medical Center, Nijmegen (Netherlands); Kooloos, Jan G [Department of Anatomy, Radboud University Nijmegen Medical Center, Nijmegen (Netherlands); Huizenga, Henk [Department of Radiotherapy, Radboud University Nijmegen Medical Center, Nijmegen (Netherlands)], E-mail: e.tanck@orthop.umcn.nl

    2010-01-21

    Bone specific, CT-based finite element (FE) analyses have great potential to accurately predict the fracture risk of deteriorated bones. However, it has been shown that differences exist between FE-models of femora scanned in a water basin or scanned in situ within the human body, as caused by differences in measured bone mineral densities (BMD). In this study we hypothesized that these differences can be reduced by re-creating the patient CT-conditions by using an anatomically shaped physical model of the lower body. BMD distributions were obtained from four different femora that were scanned under three conditions: (1) in situ within the cadaver body, (2) in a water basin and (3) in the body model. The BMD of the three scanning protocols were compared at two locations: proximally, in the trabecular bone of the femoral head, and in the cortical bone of the femoral shaft. Proximally, no significant differences in BMD were found between the in situ scans and the scans in the body model, whereas the densities from the water basin scans were on average 10.8% lower than in situ. In the femoral shaft the differences between the three scanning protocols were insignificant. In conclusion, the body model better approached the in situ situation than a water basin. Future studies can use this body model to mimic patient situations and to develop protocols to improve the performance of the FE-models in actual patients. (note)

  20. 99Tcm-MDP whole body bone scan for the ancillary diagnosis of malignant fibrous histiocytoma of bone

    International Nuclear Information System (INIS)

    Objective: To investigate the usefulness of 99Tcm-MDP whole body bone scan in bone malignant fibrous histiocytoma (BMFH). Methods: Fifteen patients (11 males, 4 females, age ranged from 23 to 60 years,average age (50.4±12.8) years) who had documented BMFH and underwent 99Tcm-MDP whole body bone scan were retrospectively analyzed. The appearance of increased uptake, decreased uptake or defect in radioactivity on bone was considered as positive. The typical scintigraphic manifestations of BMFH were summarized and compared to other radiological imaging data. Results: All 15 patients showed positive results. The lesions involved femoral in 10 cases(66.7%),46.7%(7/15) of which was distal femur. The lesions also involved sacrum, tibia, humerus, radius each in 1 case and multiple lesions in 1 case. Among 27 lesions found, 63.0% (17/27) showed strong increased radioactivity together with reduced or defect area and 37.0% (10/27) showed strong increased radioactivity only. X-ray found 20 lesions. Twelve cases underwent CT and 7 cases underwent MRI. Abnormal spots showed on CT and MRI were also positive on the whole body bone scan. Conclusions: The most common site of BMFH is femur, especially distal femur. BMFH lesions are presented as strong increased radioactivity together with sparse and defect area on bone scan. The whole body bone scan may be an auxiliary examination to evaluate whether there are multiple bone lesions and bone metastasis. (authors)

  1. Time factors associated with CT scan usage in trauma patients

    NARCIS (Netherlands)

    P.H.P. Fung Kon Jin; A.R. van Geene; K.F. Linnau; G.J. Jurkovich; K.J. Ponsen; J.C. Goslings

    2009-01-01

    INTRODUCTION: While computed tomography (CT) scan usage in acute trauma patients is currently part of the standard complete diagnostic workup, little is known regarding the time factors involved when CT scanning is added to the standard workup. An analysis of the current time factors and intervals i

  2. Segmentation of anatomical structures in chest CT scans

    NARCIS (Netherlands)

    van Rikxoort, E.M.

    2009-01-01

    In this thesis, methods are described for the automatic segmentation of anatomical structures from chest CT scans. First, a method to segment the lungs from chest CT scans is presented. Standard lung segmentation algorithms rely on large attenuation differences between the lungs and the surrounding

  3. Clinical and CT scan pictures of cerebral cysticercosis

    Energy Technology Data Exchange (ETDEWEB)

    Singounas, E.G.; Krassanakis, K.; Karvounis, P.C. (Evangelismos Hospital, Athens (Greece))

    1982-01-01

    The clinical presentations and CT scan pictures of four patients harbouring big cysticercus cysts are described. The value of CT scanning in detecting these cysts is emphasized, and also the fact that these cysts can behave as space-occyping lesions, which must be differentiated from other cystic formations.

  4. Clinical and CT scan pictures of cerebral cysticercosis

    International Nuclear Information System (INIS)

    The clinical presentations and CT scan pictures of four patients harbouring big cysticercus cysts are described. The value of CT scanning in detecting these cysts is emphasized, and also the fact that these cysts can behave as space-occyping lesions, which must be differentiated from other cystic formations. (Author)

  5. Quantitative mandibular and maxillary CT bone densitometry in surgical planning for osseointegrated dental implants

    International Nuclear Information System (INIS)

    Computed tomographic (CT) scanning of the jaw is important in the preoperative evaluation of osseointegrated dental implants. The degree of bone mineralization may have a bearing on the likelihood of successful implantation. A phantom for analysis was scanned prior to CT studies. Measurements were made in 20 patients. Bone density was sampled inferior to normal teeth and in comparable but edentulous regions, in an attempt to define the limits of normal ossification. A wide variation in bone mineral was noted in normal teeth-bearing and in edentulous bone. Three patterns of ossification are identifiable with CT. Bone densitometry may indicate those patients for whom a longer recovery period between implantation and prosthetic placement is advised

  6. Body surface area determined by whole-body CT scanning

    DEFF Research Database (Denmark)

    Villa, Chiara; Primeau, Charlotte; Hesse, Ulrik;

    2016-01-01

    Calculation of the estimated body surface area (BSA) by body height and weight has been a challenge in the past centuries due to lack of a well-documented gold standard. More recently, available techniques such as 3D laser surface scanning and CT scanning may be expected to quantify the BSA...... in an easier and more accurate way. This study provides the first comparison between BSA obtained from post-mortem whole-body CT scans and BSA calculated by nine predictive formulae. The sample consisted of 54 male cadavers ranging from 20 to 87 years old. 3D reconstructions were generated from CT scans using...

  7. SPECT/CT in the assessment of bone scintigraphy in staging of patients with oncologic diseases

    International Nuclear Information System (INIS)

    We aimed to assess the role of single photon emission computed tomography-computed tomography (SPECT/ CT) for characterizing nonconclusive lesions, observed by planar WB bone scintigraphy and to evaluate the impact of SPECT/CT on oncologic patient management. Data from 269 patients with oncologic diseases who had undergone WB BS for staging and 29 of them with nonconclusive lesions, passed SPECT/CT of a selected volume, were retrospectively analyzed. Planar scintigraphy and SPECT/CT images were independently evaluated in separate sessions to minimize recall bias. Among the 269 WB BS, in 37 patients multiple bone metastases were confirmed. In 161 patients degenerative lesions in the skeleton were defined, 42 patients were with normal bone scan and in 29 patients the results were nonconclusive for bone metastases. The fused scan after SPECT/CT imaging confirmed bone metastases in 11 (38%) patients with 27 new metastatic lesions and benign degenerative lesions in 18 patients. SPECT/CT is better than planar WB BS for characterizing equivocal lesions that are observed by bone scintigraphy, thus SPECT/CT can have a significant impact on patient management in staging the oncologic disease. (authors)

  8. CT of temporal bone - IV. inner ear

    Energy Technology Data Exchange (ETDEWEB)

    Kwon, Jae Yoon; Sung, Kyu Bo; Youn, Eun Kyoung; Park, Youn Kyeung; Lee, Young Uk [Koryo general Hospital, Seoul (Korea, Republic of)

    1990-07-15

    Temporal bone CT was done in 697 patients from April 1985 to October 1989. The abnormal findings were seen in 453 patients, which were chronic otitis media in 355 patients, fracture in 49 patients and congenital anomaly in 44 patients, etc. The abnormal findings of inner ear were observed on 46 patients. The results were summarized as follows : 1. The incidence of inner ear involvement by chronic otitis media was 7.3% (26/355 : labyrinthine fistula in 17 patients, labyrinthitis ossificans in 9 patients). Labyrinthine fistula was most commonly located on lateral semicircular canal (15/17, 88.2%). 2. Fusion of vestibule with lateral semicircular canal and formation of common cavity was demonstrated incidentally in 5 patients (0.7% of total number of temporal bone CT), and bilateral in 3 patients. 3. The incidence of inner ear anomaly in congenital ear anomaly was 11.4% (5/44). All cases were bilateral and three patients showed associated middle ear anomaly. 4. The incidence of involvement of bony labyrinth in temporal bone fracture was 10.2% (5/49). Labyrinthine fracture was seen all patients of transverse(3) and mixed fracture(1). In longitudinal fracture, labyrinthine fracture was seen in 2.2% (1/45). 5. Others were traumatic labyrinthitis ossificans(1), intracanalicular acoustic neuroma(3) and facial nerve neuroma(1)

  9. Pengaruh faktor ekspose terhadap kontras resolusi CT Scan

    OpenAIRE

    Dabukke, Hotromasari

    2015-01-01

    Research on Effects of Exposure Factors Against Contrast Resolution CT Scan in RS Pirngadi field to determine the relationship factor is exposure to the contrast in an image resolution CT scan. In the method is carried out by analyzing the density of each image of a CT scan of any change in tube voltage 80 kV, 100 kV and 140 kV with a strong current of 100 mA, 200 mA, and 400 mA. Research of the results obtained that the change in tube voltage (V) tube current (A) and measured with a dens...

  10. Preoperative CT scanning of 70 cases of rheumatic valvular disease

    Energy Technology Data Exchange (ETDEWEB)

    Take, Akira; Matuzaki, Shigeru; Oki, Shinichi (Jichi Medical School, Minamikawachi, Tochigi (Japan)) (and others)

    1992-05-01

    Seventy patients with rheumatic valvular disease were evaluated with preoperative CT scanning. The correlation of the obtained CT images to the operative findings were examined. Left atrial thrombi were found in 24 cases at the operation. CT scan had detected thrombi in 19 cases (79.2%) and echocardiography in 15 (62.5%). CT failed to find them in 5 cases in which the left atrial thrombi were less than 3 g. Echocardiogram, however, failed to detect thrombi in 9 cases, the largest being 14 g. There were 15 cases with left atrial calcification, in which 10 cases had left atrial thrombi. Nine cases out of these 10 cases had rough left atrial surface after thrombectomy. Early postoperative CT of 10 with left atrial calcification showed recurrent left atrial thrombi in 4 (40%) cases. Mitral valve calcification was found in 42 cases during operation. CT scan was able to detect it in 40 (95.2%), while echocardiogram detected in 34 cases (81.0%) (p<0.05). All mitral valves with calcification required replacement. Out of 30 cases with non calcified mitral valves, 9 underwent OMC, and the other 21 underwent mitral valve replacement. Aortic valve calcification was found in 9 out of 11 cases of aortic stenosis. All has been diagnosed by CT scan. In conclusion, 1. in detecting the left atrial thrombi, CT scan was superior to echo-cardiography, and provided useful information for planning the operative procedure including atrial approach and valvular manipulation, 2. CT scan could detect calcification of left atrial wall which had high incidence of thrombus formation and rough left atrial surface, 3. CT scan could detect calcification of both mitral and aortic valve, and showed the severity of valvular structural changes. (author).

  11. CT evaluation of primary epiphyseal bone abscesses

    Energy Technology Data Exchange (ETDEWEB)

    Azouz, E.M. (Dept. of Radiology, McGill Univ., Montreal Children' s Hospital, PQ (Canada)); Greenspan, A. (Dept. of Radiology, California Univ., Davis School of Medicine, Sacramento, CA (United States)); Marton, D. (Dept. of Radiology, Montreal Univ., Hopital Ste Justine, PQ (Canada))

    1993-01-01

    We reviewed the clinical, radiographic, and computed tomographic (CT) findings in eight children with a histologically proven diagnosis of epiphyseal or apophyseal osteomyelitis. In all cases the femur was involved: in five the osteomyelitis was localized in the femoral condyle, in two it was in the greater trochanter, and in one it was in the femoral head epiphysis. In four of the six cases of epiphyseal involvement there was associated joint effusion or septic arthritis. CT examination may demonstrate a serpentine tract, a sequestrum, cortical destruction or adjacent soft tissue swelling and can differentiate osteomyelitis from other epiphyseal lucent lesions, particularly chondroblastoma and osteoid osteoma. Early diagnosis helps avoid delays in initiating antibiotic or surgical treatment caused by the unusual (epiphyseal or apophyseal) location of the bone abscess. (orig./GD)

  12. Diagnostic accuracy of CT scan in abdominal blunt trauma

    Institute of Scientific and Technical Information of China (English)

    Javad Salimi; Khadyjeh Bakhtavar; Mehdi Solimani; Patrcia Khashayar; Ali Pasha Meysamie; Moosa Zargar

    2009-01-01

    Obiective: To evaluate the sensitivity and specificity of CT scan findings in Patients ith blunt abdominal trauma admitted to the university hospital.Methods: All the atients ith blunt abdominal trauma admitted at a tertiary teaching trauma center in Iran between 2005 and 2007 were enrolled in this study.In the absence of any clinical anifestations,he patients underwent a diagnostic CT scan.Laparatomy was performed in those with positive CT results.Others were observed for 48 hours and discharged in case no problem as reported;otherwise they underwent laparatomy.Information on patients'demographic ata,mechanism of trauma,indication for CT scan,CT scan findings,results of laparotomy ere gathered.The sensitivity,specificity and accuracy of the CT-scan images in regard ith the organ injured were calculated.The sensitivity,specificity and accuracy of the T scan were calculated in each case.Results: CT Scan had the highest sensitivity for etecting the injuries to liver (100%) and spleen (86.6%).The specificity of the method or detecting retroperitoneal hematoma (100%) and injuries to kidney (93.5%) was higher han other organs.The accuracy of CT images to detect the injuries to spleen,liver,idney and retroperitoneal hematoma was reported to be 96.1%,94.4%,91.6% and 91.6% espectively.Conclusion: The findings of the present study reveal that CT scan could econsidered as a good choice,especially for patients with blunt abdominal trauma in eaching hospitals where the radiologic academic staff is not present in the hospital in the night shifts.

  13. Age estimation by 3D CT-scans of the Borremose Woman, a Danish bog body

    DEFF Research Database (Denmark)

    Villa, Chiara; Møller Rasmussen, Maria; Lynnerup, Niels

    2011-01-01

    Non-invasive estimation of age at death has been carried out by using 3D CT scanning of a bog body discovered in 1948 in a peat bog in Borremose (Denmark). The bog body has been dated to the 8th century BC, in the last part of the Bronze Age. The skeletal structures useful for age estimation have...... been visualized from CT-scans using the Mimics software from Materialise. Extensive manual editing was necessary, as is common with bog bodies, since the bones were severely degraded and the ordinary range of Hounsfield Units (HU), used for clinical work, is not suitable. Only the cranium, the left...

  14. Bone Scintigraphy SPECT/CT Evaluation of Mandibular Condylar Hyperplasia.

    Science.gov (United States)

    Yang, Zhiyun; Reed, Tameron; Longino, Becky H

    2016-03-01

    Mandibular condylar hyperplasia (CH) is a complex developmental deformity resulting in asymmetries of the hyperplastic condyle. Bone scan SPECT is a sensitive and accurate method of detecting the growth activity of this disorder. This method can be used to quantitate the radionuclide uptake differences between the left and right condyles. Uptake differences of 10% or more between the left and right condyles, with increased uptake ipsilateral to the CH, are considered to be evidence of active growing CH. Quantitative assessment of CH is important to select an appropriate treatment course. Degenerative arthropathies of the temporomandibular joints may result in altered uptake, but this is mostly associated with the side contralateral to the CH. The CT portion of SPECT/CT is useful to assess the condylar dimensions and underlying bony changes. PMID:26111714

  15. Relationship between Hounsfield Unit in CT Scan and Gray Scale in CBCT.

    Science.gov (United States)

    Razi, Tahmineh; Niknami, Mahdi; Alavi Ghazani, Fakhri

    2014-01-01

    Background and aims. Cone-beam computed tomography (CBCT) is an imaging system which has many advantages over computed tomography (CT). In CT scan, Hounsfield Unit (HU) is proportional to the degree of x-ray attenuation by the tissue. In CBCT, the degree of x-ray attenuation is shown by gray scale (voxel value). The aim of the present study was to investigate the relationship between gray scale in CBCT) and Hounsfield Unit (HU) in CT scan. Materials and methods. In this descriptive study, the head of a sheep was scanned with 3 CBCT and one medical CT scanner. Gray scales and HUs were detected on images. Reconstructed data were analyzed to investigate relationship between CBCT gray scales and HUs. Results. A strong correlation between gray scales of CBCT and HUs of CT scan was determined. Conclusion. Considering the fact that gray scale in CBCT is the criteria in measurement of bone density before implant treatments, it is recommended because of the lower dose and cost compared to CT scan.

  16. Photon CT scanning of advanced ceramic materials

    International Nuclear Information System (INIS)

    Advanced ceramic materials are being developed for high temperature applications in advanced heat engines and high temperature heat recovery systems. Small size flaws (10 - 200 μm) and small nonuniformities in density distributions (0.1 -2%) present as long-range density gradients, are critical in most ceramics and their detection is of crucial importance. Computed tomographic (CT) imaging provides a means of obtaining a precise two-dimensional density map of a cross section through an object from which accurate information about small flaws and small density gradients can be obtained. With the use of high energy photon sources high contrast CT images can be obtained for both low and high density ceramics. In the present paper we illustrate the applicability of the photon CT technique to the examination of advanced ceramics. CT images of sintered alumina tiles are presented from which data on high-density inclusions, cracks and density gradients have been extracted

  17. CT scan findings in cerebral paragonimiasis

    Energy Technology Data Exchange (ETDEWEB)

    Udaka, Fukashi; Okuda, Bungo; Okada, Masako; Okae, Shunji; Kameyama, Masakuni (Chikamori Hospital, Kochi (Japan))

    1982-12-01

    Computed tomography was performed on 5 patients with chronic cerebral paragonimiasis. CT showed solitary or multiple, amorphous, round, or oval calcifications, and ventricular enlargement in all 5 cases. A large low-density area is also found in 4 of the 5 cases. These CT findings are compatible with previously reported findings of simple X-ray films of the skull, pneumoencephalography, and pathological studies.

  18. [Direct total body CT scan in multi-trauma patients

    NARCIS (Netherlands)

    Sierink, J.C.; Saltzherr, T.P.; Edwards, M.J.R.; Beuker, B.J.; Patka, P.; Goslings, J.C.; studiegroep, R.

    2012-01-01

    BACKGROUND: Immediate total body computed tomography (CT) scanning has become important in the early diagnostic phase of trauma care because of its high diagnostic accuracy. However, literature provides limited evidence whether immediate total body CT leads to better clinical outcome then convention

  19. CT scan prediction of late post-traumatic epilepsy.

    OpenAIRE

    D'Alessandro, R; Tinuper, P.; Ferrara, R; Cortelli, P; Pazzaglia, P; Sabattini, L; Frank, G.; Lugaresi, E

    1982-01-01

    Out of 233 patients admitted for head trauma during 1977-1978, 93 had a CT scan examination within the first 48 hours. Forty-nine of these had at least one clinical risk factor for post-traumatic epilepsy. Ten of this group developed post-traumatic epilepsy. In all cases early CT scan showed focal brain damage, which was related more significantly to post-traumatic epilepsy than to risk factors.

  20. Interpreting and Understanding CT Scanning in Head Injuries

    OpenAIRE

    Saunders, F. W.

    1984-01-01

    CT scans of neural trauma are difficult to assess. Some do not reveal enough detail, while others seem to show too much, leading to apparent discrepancies between the CT scan report and the course of therapy. This confuses the patient's family, who often ask the family physician about the type of treatment being given and the ultimate prognosis. Their concerns can often be alleviated if the family physician understands and can explain these apparent discrepancies. This article describes sever...

  1. CT scan findings of fungal pneumonia

    International Nuclear Information System (INIS)

    The importance of fungal infection of the lung in immunocompromised patients has increased substantially during the last decades. Numerically the most patients are those with neutropenia, e.g. patients with malignancies or solid organ and stem cell transplantation, chemotherapy, corticosteroid use and HIV infection. Although fungal infections can occur in immunocompetent patients, their frequency in this population is rare. The clinical symptoms such as fever accompanied with non-productive cough are unspecific. In some patients progression to hypoxemia and dyspnea may occur rapidly. In spite of improved antifungal therapy morbidity and mortality of these infections are still high. Therefore an early and non-invasive diagnosis is very important. That is why CT and even better High-Resolution-CT (HR-CT) is a very important modality in examining immunocompromised patients with a probability of fungal infection. CT is everywhere available and, as a non-invasive method, able to give the relevant diagnose efficiently. This paper should give an overview about the radiologic findings and possible differential diagnosis of diverse pulmonary fungal infections in CT. Pneumonias caused by Aspergillus, Cryptococcus, Candida, Histoplasma, Mucor and Geotrichum capitatum are illustrated. (orig.)

  2. Spinal CT scan, 2. Lumbar and sacral spines

    Energy Technology Data Exchange (ETDEWEB)

    Nakagawa, Hiroshi (Aichi Medical Univ., Aichi (Japan))

    1982-08-01

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

  3. Super bone scans on bone scintigraphy in patients with metastatic bone tumor

    International Nuclear Information System (INIS)

    Eight patients with malignant tumor (3 with gastric cancer, 4 with prostatic cancer, 1 with transitional cell carcinoma), which showed diffusely increased uptake of 99mTc labelled phosphorous compound in axial skeleton (''Super Bone Scan'') on bone scintigraphy were clinically studied. No relationship with its histological type of the tumor was recognized. All cases revealed extremely high serum ALP concentration, which might reflect increased osteoblastic activity. Furthermore, on bone roentgenograms all cases showed predominantly osteosclerotic change in the metastatic bones, while some did locally osteolytic change. In three cases with gastric cancer, although they had diffuse skeletal metastases, two had no evidence of liver metastases. Thus, it seemed that clinical study of patients with ''Super Bone Scan'' was interesting to evaluate the mechanism of accumulation of 99mTc labelled phosphorous compound to bone and bone metabolism, and the pathophysiology in the pathway of bone metastases. (author)

  4. Scanning of Bone Marrow in Haematopoietic Disorders

    International Nuclear Information System (INIS)

    Scanning can help evaluate size and distribution of the haematopoietic marrow, a difficult task by aspiration or biopsy. With the 61-hole focusing gold-tungsten Oak Ridge National Laboratory Scanner, the marrow organ has been clearly delineated by means of intravenous colloidal Au198, it being known that reticulo-endothelial function in the marrow correlates with areas of haematopoiesis. Patients with normal haematopoiesis and with a variety of blood disorders such as focal marrow lesions, acute and chronic leukaemia, polycythaemiavera, myelofibrosis, multiple myeloma, and lymphoma have been scanned. Because of the reticulo-endothelial activity in liver and spleen, the marrow pattern is obscured in the mid-trunk. Vertebral bodies, intervertebral discs, pelvis and long bones are outlined, and, in the thorax, the sternum and thoracic vertebrae. Focal lesions have also been found. Because of respiratory motion, individual ribs are not seen. In expanded marrow, the knee region can be shown, including the joint space. It has been possible to correlate these scans with aspiration biopsy and with linear scans. Because relatively large doses of Au198 are required, other isotopes are being investigated. An improved whole- body scanner is being tested for more practical scans. (author)

  5. CT of temporal bone II. OMPC

    Energy Technology Data Exchange (ETDEWEB)

    Ham, So Hie; Ahn, Jung Sook; Sung, Kyu Bo; Woo, Won Hyung [Koryo General Hospital, Seoul (Korea, Republic of)

    1987-10-15

    High resolution CT is well known excellent modality for evaluation of fine ear structures and its changes, but is not usual method for detection of inflammatory disease of ear. Forty cases of OMPC were reviewed advantage and advantage and limitations also evaluated. The results were as follows: 1. On CT findings of OMPC, abnormalities were external auditory canal in 14 cases(35%), tympanic membrane in 31 cases (77.5%), soft tissue mass in middle ear cavity and/or mastoid antrum in 34 cases (85%), middle ear effusion in 9 cases (22.5%), and bony labyrinth in 5 cases (12.5%). 2. Partial erosion and missing of ossicles were long process and lenticular process of incus, body of incus, head of malleus, and stapes in order. 3. Advantage of temporal bone CT were early detection of soft tissue mass, evaluation of extent of disease, destruction of bony structure and ossicular destruction. 4. Differentiation of cholesteatoma and granulation was difficult and examination of superstructures such as stapes and facial nerve canal were limit0008.

  6. Classication Methods for CT-Scanned Carcass Midsections

    DEFF Research Database (Denmark)

    Skytte, Jacob Lercke; Dahl, Anders Lindbjerg; Larsen, Rasmus;

    2011-01-01

    Computed tomography (CT) has successfully been applied in medical environments for decades. In recent years CT has also made its entry to the industrial environments, including the slaughterhouses. In this paper we investigate classication methods for an online CT system, in order to assist...... in the segmentation of the outer fat layer in the mid- section of CT-scanned pig carcasses. Prior information about the carcass composition can potentially be applied for a fully automated solution, in order to optimize the slaughter line. The methods comprise Markov Random Field and contextual Bayesian classication...

  7. Evaluation of the accuracy of CT head scanning

    International Nuclear Information System (INIS)

    In the early years of C.T. scanning, most publications simply described heterogeneous groups of cases where the technique had been applied and where the diagnosis was known with reasonable certainty. No major effort was made to detect those cases falsely reported as negative scans. If the sensitivity of C.T. scanning is to be effectively assessed, the results of this study must be compared with some other method that gives the investigator an appraisal of all lesions that are present. (orig./VJ)

  8. Automated alignment of serial thoracic scans using bone structure descriptors

    Science.gov (United States)

    Gavrielides, Marios A.; Petrick, Nicholas; Myers, Kyle J.

    2007-03-01

    In this manuscript we present an automated algorithm for the alignment of thoracic scans using descriptors of bone structures. Bone structures were utilized because they are expected to be less susceptible to sources of errors such as patient positioning and breath hold. The algorithm employed the positioning of ribs relative to the spinal cord along with a description of the scapula. The spinal cord centroid was detected by extracting local maxima of the distance transform followed by point tracing along consecutive slices. Ribs were segmented using adaptive thresholding followed by the watershed algorithm to detach ribs from the vertebra, and by imposing requirements of rib proximity to the lung border. The angles formed between the spinal cord centroid and segmented rib centroids were used to describe rib positioning. Additionally, the length of the scapula was extracted in each slice. A cost function incorporating the difference of features from rib positioning and scapula length between two slices was derived and used to match slices. The method was evaluated on a set of 12 pairs of full and partial CT scans acquired on the same day. Evaluation was based on whether the slices showing a nodule at its maximum diameter in each scan were matched. Full-to-partial and partial-to-full alignment were performed. Results showed that the proposed metric matched nodule slices within an average distance of 1.08 and 1.17 slices from the target for full-to-partial and partial-to-full alignment respectively. These preliminary results are encouraging for using this method as a first step in an overall process of temporally analyzing CT lung nodules.

  9. The clinical value of SPECT/CT fusion imaging in the diagnosis of bone metastasis of breast cancer

    International Nuclear Information System (INIS)

    Objective: To evaluate the clinical value of SPECT/CT fusion imaging in the diagnosis and differential diagnosis the characteristic of the whole body bone scan radioactive hot lesions in patients with breast cancer. Methods: The abnormal radioactive hot lesions of whole body bone scan in 25 patients with breast cancer underwent SPECT/CT fusion imaging immediately. Another whole body bone scan and SPECT/CT fusion imaging were carried out 4 to 8 months later in all these patients. The whole body bone scan images, SPECT/CT images and fusion images were analyzed independently by two experienced nuclear medicine physicians and some of the equivocal CT images were analyzed by an experienced radiologist. Results: Among all the 37 abnormal radioactive hot bone lesions, 29 (29/37, 78.38%) lesions were confirmed metastatic lesions,including 2 vertebral lesions classified as benign lesions on the basis of the first examinations data; and 8 lesions were benign,including a rib lesion classified as benign lesion according to the first examinations data. The difference between whole body bone scan and SPECT/CT examination was statistically significant (χ2=6.975, P<0.05). The bone metastases are located mainly in spine and ribs. The sensitivity,specificity, positive and negative predictive values, and accuracy of whole-body bone scan and SPECT/CT fusion imaging were 82.76%, 75.00%, 92.31%, 54.55%, 81.08% and 93.10%, 87.50%, 96.43%, 77.78%, 91.89%, respectively. The area under the receiver operating characteristics curve was 0.860±0.056 for whole body bone scan and 0.974±0.020 for SPECT/CT. The area under the curve for SPECT/CT was significantly larger compared with the whole body bone scan (χ2=9.924, P<0.001). Conclusions: SPECT/CT fusion imaging is better than whole body bone scan alone to characterize the abnormal bone radioactive hot lesions and it can improve the accuracy of diagnosis. The patients should repeat the modality 4 to 8 months later if necessary. (authors)

  10. Extraction of bone structure with a single-scan skeletonization driven by distance

    OpenAIRE

    Arlicot, Aurore; NORMAND, Nicolas; Amouriq, Yves; Guédon, Jeanpierre

    2011-01-01

    Shape description is an important step in image analysis. Skeletonization methods are widely used in image analysis since they are a powerful tool to describe a shape. This paper presents a new single-scan skeletonization using different diskrete distances. The application of this method is the extraction of caracteristics from µCT images in order to estimate the bone state.

  11. Diagnosis of bone metastases in prostate cancer patients with SPECT/CT

    International Nuclear Information System (INIS)

    Full text: Introduction: The bone metastases are the first and foremost place for metastases of about 80% of patients with prostate cancer. The diagnosis of bone metastases can be achieved by various imaging methods. They visualize different aspects of the bone tissue according to the bone density, water content, blood flow and metabolism. The bone scintigraphy is a relatively sensitive, inexpensive and low exposure method, which displays the entire skeleton in one session. Materials and Methods: The bone scintigraphy is performed with gamma camera for whole body scanning and SPECT/CT in case of lesions of uncertain nature. 99mTs -MDP (methylene diphosphonate) was used which localizes in bones through physicochemical absorption of phosphorus groups on the calcium of the hydroxyapatite. A pathologically increased focal inclusion was observed in case of overproduction (activation of osteoblasts) with increased mineral metabolism in all pathologies with osteoblastic reactions, such as primary and metastatic tumors, inflammation, fracture, degenerative changes. The absence of bone (osteoclasts activation) is visualized as a cold zone, with or without a hot edge. For multiple metastases the scintigraphic image is typical. In solitary lesions, more careful assessment and use of other imaging methods (SPECT / CT, CT, MRI) is needed in order to differentiate benign from malignant foci. Results: The hybrid image from the SPECT / CT allows precise anatomical localization of pathological foci, which in most of the cases can differentiate benign from malignant lesions. The CT image displays lytic foci, missed by the scintigraphy and improves the scintigraphic image by correction for scattered radiation. The use of low-dose CT reduces radiation exposure more than 40 %. In a retrospective study of 167 newly diagnosed patients with prostate cancer, bone metastases were detected in 20.8%. In asymptomatic patients with Glison score 5 and PSA> 15 and in all patients with T3 - 4 and

  12. Congenital cystic eye-A case report with CT scan

    Directory of Open Access Journals (Sweden)

    Pillai A

    1987-01-01

    Full Text Available A case of Congential cystic eye in a two month old girl is reported. This rare condition is recognised at birth as a large orbital mass in place of the normal eye. This is perhaps the first reported case with a CT Scan. The CT appearance suggests that the defect in embryogenesis is not confined to the optic vesicle but involves other parts of the brain also.

  13. [Usefulness of CT scan in the diagnosis of pulmonary aspergilloma].

    Science.gov (United States)

    Gea, J; Arán, X; Sauleda, J; Broquetas, J M; Alegret, X; Bartrina, J

    1991-05-01

    Early diagnosis and precise anatomical localization of aspergillomas are essential for an effective treatment of their complications. We have evaluated the usefulness of thorax CT scan in the fulfillment of these objectives. Nine consecutive patients were studied with a presumable diagnosis of pulmonary aspergilloma. A thorax CT scan was performed in all patients (sections every 5 to 10 mm) in lying position and with lateral mobilizations. This technique allowed to rule out as fibrotic lesions some of the images previously attributed to mycetomas by conventional X-ray. On the other hand it helped to identify small size aspergillomas, to precise their localization and to demonstrate the possible communication between the main cavity and bronchial tree. In three patients who died in the period immediately following the study an excellent correlation between CT scan and underlying pathological lesions was observed. PMID:1891635

  14. Radio-isotope bone scanning in suspected osteomyelitis in children

    International Nuclear Information System (INIS)

    The usefulness of radio-isotope bone scanning in suspected osteomyelitis has been widely acclaimed. Fourteen children had rectilinear bone scans performed three hours after injection of Tcsup(99m) methylene diphosphonate. A diagnostic accuracy of 56% was achieved, which is lower than in other series. The reasons for this are discussed and the value of bone scanning in the evaluation of osteomyelitis is questioned. (orig.)

  15. MRI of patients with cerebral palsy and normal CT scan

    Energy Technology Data Exchange (ETDEWEB)

    Bogaert, P. van; Szliwowski, H.B. (Hopital Erasme, Brussels (Belgium). Dept. of Neurology); Baleriaux, D.; Christophe, C. (Hopital Erasme, Brussels (Belgium). Dept. of Radiology (Neuroradiology))

    1992-02-01

    Three children with clinical evidence of cerebral palsy (CP) and normal cerebral computed tomography (CT) scans were evaluated by magnetic resonance imaging (MRI) to identify CT-undetectable white matter lesions in the watershed zones of arterial territories. The two patients with spastic diplegia showed bilateral lesions either in the subcortical regions or in the occipital periventricular regions. The patient with congenital hemiplegia exhibited unilateral lesions in the periventricular region. We conclude that MRI is more informative than CT for the evaluation of patients with CP. (orig.).

  16. MRI of patients with cerebral palsy and normal CT scan

    International Nuclear Information System (INIS)

    Three children with clinical evidence of cerebral palsy (CP) and normal cerebral computed tomography (CT) scans were evaluated by magnetic resonance imaging (MRI) to identify CT-undetectable white matter lesions in the watershed zones of arterial territories. The two patients with spastic diplegia showed bilateral lesions either in the subcortical regions or in the occipital periventricular regions. The patient with congenital hemiplegia exhibited unilateral lesions in the periventricular region. We conclude that MRI is more informative than CT for the evaluation of patients with CP. (orig.)

  17. NCICT: a computational solution to estimate organ doses for pediatric and adult patients undergoing CT scans.

    Science.gov (United States)

    Lee, Choonsik; Kim, Kwang Pyo; Bolch, Wesley E; Moroz, Brian E; Folio, Les

    2015-12-01

    We developed computational methods and tools to assess organ doses for pediatric and adult patients undergoing computed tomography (CT) examinations. We used the International Commission on Radiological Protection (ICRP) reference pediatric and adult phantoms combined with the Monte Carlo simulation of a reference CT scanner to establish comprehensive organ dose coefficients (DC), organ absorbed dose per unit volumetric CT Dose Index (CTDIvol) (mGy/mGy). We also developed methods to estimate organ doses with tube current modulation techniques and size specific dose estimates. A graphical user interface was designed to obtain user input of patient- and scan-specific parameters, and to calculate and display organ doses. A batch calculation routine was also integrated into the program to automatically calculate organ doses for a large number of patients. We entitled the computer program, National Cancer Institute dosimetry system for CT(NCICT). We compared our dose coefficients with those from CT-Expo, and evaluated the performance of our program using CT patient data. Our pediatric DCs show good agreements of organ dose estimation with those from CT-Expo except for thyroid. Our results support that the adult phantom in CT-Expo seems to represent a pediatric individual between 10 and 15 years rather than an adult. The comparison of CTDIvol values between NCICT and dose pages from 10 selected CT scans shows good agreements less than 12% except for two cases (up to 20%). The organ dose comparison between mean and modulated mAs shows that mean mAs-based calculation significantly overestimates dose (up to 2.4-fold) to the organs in close proximity to lungs in chest and chest-abdomen-pelvis scans. Our program provides more realistic anatomy based on the ICRP reference phantoms, higher age resolution, the most up-to-date bone marrow dosimetry, and several convenient features compared to previous tools. The NCICT will be available for research purpose in the near future.

  18. CT scan patterns of pulmonary alveolar proteinosis in children

    International Nuclear Information System (INIS)

    Background. To study computed tomographic (CT) findings in children with pulmonary alveolar proteinosis (PAP) more extensively. Objective. To describe the CT features at the time of diagnosis and after therapeutic broncho-alveolar lavage (BAL). Materials and methods. We retrospectively reviewed the CT scans of five children (aged 3 months to 4 years) examined because of incidental bronchitis (n = 1), disease in a sibling (n = 1) and relapsing fever, cough and dyspnoea (n = 3). Each patient had an initial CT scan. Two asymptomatic cases were not treated but were followed up by plain chest films. The other three had BAL and follow-up CT. Results. Initial CT in all cases showed a diffuse reticulomicronodular pattern associated in three cases with posterior bilateral alveolar infiltrates. CT in the two asymptomatic patients remained unchanged or slightly improved without BAL. After BAL, a variable decrease of lung infiltrates was observed. Conclusions. Correlation between the extent of alveolar consolidation and severity of disease was found. Anatomical and pathological considerations allow us to consider that the classical reticulomicronodular pattern is not due to an interstitial infiltration but to alveoli filled with the abnormal material characteristic of PAP. (orig.)

  19. CT scan patterns of pulmonary alveolar proteinosis in children

    Energy Technology Data Exchange (ETDEWEB)

    Albafouille, V.; Sayegh, N.; Coudenhove, S. de; Mamou-Mani, T.; Hassine, A.; Brunelle, F. [Hopital Necker-Enfants Malades, Paris (France). Dept. of Paediatric Radiology; Scheinmann, P.; Blic, J. de [Hopital Necker-Enfants Malades, Paris (France). Dept. of Pneumology; Jaubert, F. [Hopital Necker-Enfants Malades, Paris (France). Dept. of Pathology

    1999-03-01

    Background. To study computed tomographic (CT) findings in children with pulmonary alveolar proteinosis (PAP) more extensively. Objective. To describe the CT features at the time of diagnosis and after therapeutic broncho-alveolar lavage (BAL). Materials and methods. We retrospectively reviewed the CT scans of five children (aged 3 months to 4 years) examined because of incidental bronchitis (n = 1), disease in a sibling (n = 1) and relapsing fever, cough and dyspnoea (n = 3). Each patient had an initial CT scan. Two asymptomatic cases were not treated but were followed up by plain chest films. The other three had BAL and follow-up CT. Results. Initial CT in all cases showed a diffuse reticulomicronodular pattern associated in three cases with posterior bilateral alveolar infiltrates. CT in the two asymptomatic patients remained unchanged or slightly improved without BAL. After BAL, a variable decrease of lung infiltrates was observed. Conclusions. Correlation between the extent of alveolar consolidation and severity of disease was found. Anatomical and pathological considerations allow us to consider that the classical reticulomicronodular pattern is not due to an interstitial infiltration but to alveoli filled with the abnormal material characteristic of PAP. (orig.) With 3 figs., 1 tab., 16 refs.

  20. Analysis of cranial CT-scan findings in cerebral palsy

    Energy Technology Data Exchange (ETDEWEB)

    Wada, F.; Andoh, T.; Une, K.; Takamatsu, T. (Kitakyushu Municipal Sogo-Ryoiku Center (Japan))

    1981-06-01

    CT-scan findings of 87 cerebral palsied children were studied. They consist of 23 cases of spastic quadriplegia, 9 cases of diplegia, 12 cases of paraplegia, 24 cases of athetosis and mixed type, and 19 cases of hemiplegia. In the former four types, ventricular dilatation and cortical atrophy were measured and abnormal changes in cerebral substance and cerebellar atrophy were observed. Spastic quadriplegia showed most intense changes in every aspect of the abnormalities, while paraplegia had almost normal appearance. Athetosis and mixed type had moderate changes. Hemiplegia always showed asymmetrical view on CT-scan, dilatation of lateral ventricle or atrophy of hemisphere in contralateral side being observed.

  1. Analysis of cranial CT-scan findings in cerebral palsy

    International Nuclear Information System (INIS)

    CT-scan findings of 87 cerebral palsied children were studied. They consist of 23 cases of spastic quadriplegia, 9 cases of diplegia, 12 cases of paraplegia, 24 cases of athetosis and mixed type, and 19 cases of hemiplegia. In the former four types, ventricular dilatation and cortical atrophy were measured and abnormal changes in cerebral substance and cerebellar atrophy were observed. Spastic quadriplegia showed most intense changes in every aspect of the abnormalities, while paraplegia had almost normal appearance. Athetosis and mixed type had moderate changes. Hemiplegia always showed asymmetrical view on CT-scan, dilatation of lateral ventricle or atrophy of hemisphere in contralateral side being observed. (author)

  2. Treatment of Alzheimer Disease With CT Scans

    Science.gov (United States)

    Moore, Eugene R.; Hosfeld, Victor D.; Nadolski, David L.

    2016-01-01

    Alzheimer disease (AD) primarily affects older adults. This neurodegenerative disorder is the most common cause of dementia and is a leading source of their morbidity and mortality. Patient care costs in the United States are about 200 billion dollars and will more than double by 2040. This case report describes the remarkable improvement in a patient with advanced AD in hospice who received 5 computed tomography scans of the brain, about 40 mGy each, over a period of 3 months. The mechanism appears to be radiation-induced upregulation of the patient’s adaptive protection systems against AD, which partially restored cognition, memory, speech, movement, and appetite. PMID:27103883

  3. The CT flare response of metastatic bone disease in prostate cancer

    Energy Technology Data Exchange (ETDEWEB)

    Messiou, Christina; deSouza, Nandita M. (Cancer Research UK Clinical Magnetic Resonance Research Group, Inst. of Cancer Research and Royal Marsden NHS Foundation Trust, Surrey (United Kingdom)), email: Christina.Messiou@icr.ac.uk; Cook, Gary (Dept. of Nuclear Medicine, Royal Marsden NHS Foundation Trust, Surrey (United Kingdom)); Reid, Alison H.M.; Attard, Gerhardt; Dearnaley, David; deBono, Johann S. (Inst. of Cancer Research and Royal Marsden NHS Foundation Trust, Surrey (United Kingdom))

    2011-06-15

    Background New or worsening bone lesions in patients responding to treatment, known as the flare phenomenon is well described on 99mTc-MDP bone scintigraphy, but to our knowledge has not previously been described on CT. The appearance of new or worsening bone sclerosis on CT in patients with prostate cancer may therefore be erroneously classified as disease progression. Purpose To assess the incidence of osteoblastic healing flare response at 3-month CT assessment in patients with castrate-resistant prostate cancer and to identify associated features that enable differentiation from progressive metastatic bone disease at 3 months. Material and Methods CT scans of 67 patients with castrate-resistant prostate cancer undergoing treatment were reviewed by a radiologist blinded to clinical outcome. Changes in number, size, and density of metastatic bone lesions were documented and Response Evaluation Criteria in Solid Tumours (RECIST) in soft tissue lesions, alkaline phosphatase, prostate specific antigen, and 99mTc-MDP bone scans were used for correlation. Results Of the 39 patients who had 3- and 6-month follow-up, eight patients (21%) demonstrated an increase in number, size, or density of sclerotic lesions on the 3-month CT scan despite improvement in PSA and soft tissue lesions. Three out of eight patients (8%) maintained partial response/remained stable at follow-up and were defined as showing a flare response: in this group bone metastases evident on CT showed a qualitative and quantitative increase in density and no lesions faded at 3 months. In contrast, in all patients who progressed at 3 months by PSA/RECIST criteria (n = 8) bone lesions showed a mixed pattern with some lesions increasing and others decreasing in density. Conclusion The incidence of flare response of metastatic bone disease evident at 3-month post-treatment CT in patients with prostate cancer undergoing systemic treatment is 8%. In patients with falling PSA and stable/responding soft tissue

  4. Technical Note: Reliability of Suchey-Brooks and Buckberry-Chamberlain methods on 3D visualizations from CT and laser scans

    DEFF Research Database (Denmark)

    Villa, Chiara; Buckberry, Jo; Cattaneo, Cristina;

    2013-01-01

    -Brooks and the Buckberry-Chamberlain methods on 3D visualizations based on CT-scans and, for the first time, on 3D visualizations from laser scans. We examined how the bone features can be evaluated on 3D visualizations and whether the different modalities (direct observations of bones, 3D visualization from CT......-scan and from laser scans) are alike to different observers. We found the best inter-observer agreement for the bones versus 3D visualizations, with the highest values for the auricular surface. Between the 3D modalities, less variability was obtained for the 3D laser visualizations. Fair inter....... In conclusion, these methods were developed for dry bones, where they perform best. The Suchey-Brooks method can be applied on 3D visualizations from CT or laser, but with less accuracy than on dry bone. The Buckberry-Chamberlain method should be modified before application on 3D visualizations. Future...

  5. Healed or non-healed? computed tomography (CT) visualisation of morphology of bite trace ichnotaxa on a dinosaur bone

    DEFF Research Database (Denmark)

    Jacobsen, Aase Roland; Lauridsen, Henrik; Fiirgaard, Bente;

    2015-01-01

    of stereomicroscopy and a radiologist analysed the CT scans. Sixteen different scanner settings were used to optimise the CT parameters and avoid signal at tenuation, in the form of hypointense artefacts in the central trabeculated part of the bone fragment. The use of CT scanning provided information on internal...... examined by correlating traditional naked-eye in spection with computed to mography (CT) imaging, used to visualise the internal morphology of the bite traces and in particular, to clarify the appearance of one possibly healed bite trace. A forensic pathologist visually examined the bone with the aid...... morphology from the vicinity of the bite trace, including hyperdense zones, not identified using visual inspection alone. By applying the extended CT scale, the dense and radiopaque cortical bone layer could be clearly identified and applied as a pathomorphological marker to correctly distinguish non...

  6. Evaluation of Response to Therapy in a Patient with Lung Cancer: Correlation of Sclerotic Bone Lesions with F 18 FDG PET/CT and Bone Scintigraphy

    Directory of Open Access Journals (Sweden)

    Filiz Özülker

    2011-04-01

    Full Text Available A 64-year-old male patient with small cell lung cancer underwent Fluorine-18 fluorodeoxyglucose (F 18 FDG positron emission tomography (PET/CT scan which revealed multiple F 18 FDG uptake in the spine, both humeri, ribs, pelvis and proximal long bones. There was no obvious lytic or sclerotic bone destruction accompanying these lesions on CT component of the study. After the patient received six courses of chemotherapy a repeat F 18 FDG-PET/CT was performed for evaluation of therapy response. The PET/CT showed the presence of multiple sclerotic lesions on CT without FDG uptake, corresponding to the bone lesions on the previous PET/CT scan. A concomitant Tc 99m Methylene diphosphonate (Tc 99m MDP bone scintigraphy (BS revealed no pathologically increased Tc 99m MDP uptake in the skeletal system. The FDG avid lesions in the skeletal system, which were not sclerotic initially, were transformed into FDG non-avid sclerotic lesions after chemotherapy. This was attributed to the direct effect of previous successful therapy for bone metastases, leading to the transformation of metabolically active disease, into blastic metabolically inactive metastases. In conclusion, a F 18 FDG negative bone lesion, which is sclerotic on CT, may represent post-treatment osteoblastic change rather than active tumor and BS might play a role in the discrimination of these two situations. (MIRT 2011; 20: 29-33

  7. Artifacts and pitfalls of high-resolution CT scans.

    Science.gov (United States)

    Hahn, F J; Chu, W K; Anderson, J C; Dobry, C A

    1985-01-01

    Artifacts on CT images have been observed since the introduction of CT scanners. Some artifacts have been corrected with the improvement of technology and better understanding of the image formation and reconstruction algorithms. Some artifacts, however, are still observable in state-of-the-art high-resolution scans. Many investigations on CT artifacts have been reported. Some artifacts are obvious and some are similar to patterns commonly associated with pathological conditions. The present report summarizes some of the causes of artifacts and presents some artifacts that mimic pathology on clinical scans of the head and spine. It is the intention of this report to bring these artifacts and potential pitfalls to the attention of the radiologists so that misinterpretation can be avoided.

  8. Diagnostic Utility of CT Scan for Acute Headache

    Directory of Open Access Journals (Sweden)

    J Gordon Millichap

    2009-08-01

    Full Text Available ED records for 364 children 2 to 5 years of age who presented to the Children’s National Medical Center ED, Washington, DC, between July 1, 2003, and June 30, 2006, with headache as their chief complaint, were examined to determine whether CT scans led to better acute management, justifying the risk of radiation.

  9. Harms of CT scanning prior to surgery for suspected appendicitis.

    Science.gov (United States)

    Rogers, William; Hoffman, Jerome; Noori, Naudereh

    2015-02-01

    In this brief analysis we compare the risks and benefits of performing a CT scan to confirm appendicitis prior to surgery instead of operating based on the surgeon's clinical diagnosis. We conclude that the benefit of universal imaging is to avoid 12 unnecessary appendectomies but the cost of those 12 avoided surgeries is one cancer death due to the imaging. PMID:25429870

  10. Serial CT scans and Menkes' kinky hair disease

    Energy Technology Data Exchange (ETDEWEB)

    Nakada, Eizo; Kameyama, Junji; Yoshimitsu, Hajime; Mori, Mikio; Tanaka, Mutsuo; Yoshimitsu, Kazunori.

    1988-02-01

    Menkes' kinky hair disease is a sex-linked recessive disorder of copper metabolism, characterized by progressive psychomotor deterioration, seizures, and peculiar hair structure. We examined serial CT scans of patients with this disease. A 2,210-g male infant was delivered after an uneventful gestation of 36 weeks. His one-minute Apgar score was 9. His uncle had died at 1 year of age. His first cousin was also diagnosed as having Menkes' kinky hair disease when our patient was 2 years old. Shortly after birth he had mild respiratory distress. At 5 days of age, he developed setting-sun signs. The first CT scan, at 10 days of age, revealed mild posterior fossa hemorrhages. At 3 months of age, myoclonic seizures began, and the CT scan revealed subdural effusion and mild brain atrophy. The seizures were controllable by using phenobarbital, valproic acid, and nitrazepam. He did not follow light or a fixate, but the fundi were normal. He was diffusely hypotonic. At 9 months of age, the seizures became uncontrollable. The CT scans at 15 and 31 months of age showed subdural hemorrhage and/or brain atrophy. At 15 months of age, the serum copper level was 42 ..mu.. g/dl, while the serum ceruloplasmin level was 3.2 mg/dl. He exhibited severe developmental failure. At 4 years of age, he died.

  11. Temporal bone trauma: correlative study between CT findings and clinical manifestations

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jung Hee; Kim, Hyung Jin; Kim, Jae Hyoung [College of Medicine, Gyeongsang National University, Jinju (Korea, Republic of)

    1994-11-15

    To assess how accurately computed tomography (CT) can demonstrate the abnormal findings which are believed to cause the clinical signs and symptoms of hearing loss (HL), vertigo and facial paralysis (FP) in patients with temporal bone trauma. The authors studied CT scans of 39 ears in 35 patients with temporal bone trauma. CT scans were performed with 1-1.5 mm slice thickness and table incrementation. Both axial and coronal scans were obtained in 32 patients and in three patients only axial scans were obtained. We analyzed CT with special reference to the structural abnormalities of the external auditory canal, middle ear cavity, bony labyrinth, and facial nerve canal, and correlated these findings with the actual clinical signs and symptoms. As to hearing loss, we evaluated 32 ears in which pure tone audiometry or brainstem evoked response audiometry had been performed. With respect to the specific types of HL, CT accurately showed the abnormalities in 84% (16/19) in conductive HL, 100% (2/2) in sensorineural HL, and 25% (2/8) for mixed HL. When we categorized HL simply as conductive and sensorineural, assuming that mixed be the result of combined conductive and sensorineural HL, CT demonstrated the abnormalities in 89% (24/27) for conductive HL and 50% (5/10) for sensorineural HL. Concerning vertigo and FP, CT demonstrated abnormalities in 67%(4/6), and 29% (4/14), respectively. Except for conductive HL, CT seems to have a variable degree of limitation for the demonstration of the structural abnormalities resulting sensorineural HL, vertigo or facial paralysis. It is imperative to correlate the CT findings with the signs and symptoms in those clinical settings.

  12. The role of bone scanning in the cancer patient

    International Nuclear Information System (INIS)

    The past few years have been notable by the torrent of work which has served to establish bone scanning as one of the most useful nuclear medicine procedures. The quantitative radiopharmacology of the sup(99m) Tc phosphates has great possibilities for obtaining reliable and reproducible bone scans of high quality. Bone scans are extremely useful in staging malignant disease, particularly with primaries involving breast, prostate, lung, kidney and thyroid, but are also useful in the workup of the lymphomas, in the female genital cancer tract, and primary bone malignancy. The full potential of these compounds in the care of the cancer patient has been confirmed. (orig.)

  13. Expiratory CT scan in patients with normal inspiratory CT scan: a finding of obliterative bronchiolitis and other causes of bronchiolar obstruction

    OpenAIRE

    Gaeta, Michele; Minutoli, Fabio; Girbino, Giuseppe; Murabito, Alessandra; Benedetto, Caterina; Contiguglia, Rosario; Ruggeri, Paolo; Privitera, Salvatore

    2013-01-01

    Expiratory CT scan is usually obtained as supplement to normal inspiratory CT scan to recognize air-trapping, which is expression of small airways obstruction. In some patients the air-trapping may be the only sign of an early-stage small airways disease in an otherwise normal lung. The purpose of this article is to illustrate pathologic conditions, namely obliterative bronchiolitis, in which expiratory CT scan can be abnormal despite normal inspiratory CT examination, and to highlight indica...

  14. Comparison of the Accuracy of Panoramic Radiography, Coronal and Axial Ct Scan in Diagnosis of Mandibular Fractures

    OpenAIRE

    HR Mansourian; AR Sadr-Arhami; F Ezoddini-Ardakani; Sh Azari; P Dabirmoghadam

    2006-01-01

    Introduction: Mandibular fracture is the most common facial bone fracture due to facial trauma. A variety of imagings have been used for diagnosis of mandibular fractures. However, the choice of imaging for diagnosis of mandibular fractures is controversial.Present study compares the accuracy of the three most common imaging methods in mandibular fracture diagnosis; panoramic radiography, coronal CT and axial CT scan. Methods: This cross sectional diagnostic study was performed on 45 patients...

  15. Craniofacial and temporal bone CT findings in cleidocranial dysplasia

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez, Guido E. [Massachusetts General Hospital and Harvard Medical School, Department of Radiology, Boston, MA (United States); Clinica Alemana de Santiago, Departamento de Imagenes, Santiago (Chile); Caruso, Paul A.; Curtin, Hugh D. [Massachusetts Eye and Ear Infirmary and Harvard Medical School, Department of Radiology, Boston, MA (United States); Small, Juan E. [Massachusetts General Hospital and Harvard Medical School, Department of Radiology, Boston, MA (United States); Massachusetts Eye and Ear Infirmary and Harvard Medical School, Department of Radiology, Boston, MA (United States); Jyung, Robert W. [Massachusetts Eye and Ear Infirmary and Harvard Medical School, Department of Otology, Boston, MA (United States); Troulis, Maria J. [Massachusetts General Hospital and Harvard Medical School, Department of Oral and Maxillofacial Surgery, Boston, MA (United States)

    2008-08-15

    Cleidocranial dysplasia (CCD) is a multistructural polyostotic genetic disorder that results from mutation of the CBFA1 gene. Hearing loss is a frequent finding in CCD. We describe the CT craniofacial findings in CCD and provide a comprehensive discussion of the CT temporal bone findings in these patients. (orig.)

  16. MR and CT findings of temporal bone langerhans cell histiocytosis

    Energy Technology Data Exchange (ETDEWEB)

    Bae, Jae Ig; Lee, Hee Jung; Kim, Heung Sik [Keimyung Univ. School of Medicine, Dongsan Medical Center, Taegu (Korea, Republic of)

    2001-11-01

    To describe the MRI and CT findings of temperal bone langerhans cell histiocytosis. The MRI (n=8) and CT (n=7) findings of nine lesions of temporal bone Langerhans cell histiocytosis in six children were retrospectively reviewed. Eight lesions were pathologically confirmed and one was clinically diagnosed. The findings were analyzed for bilaterality, location, lesion extent, signal intensity, the attenuation of soft tissue lesions seen at MRI or precontrast CT, enhancement pattern at MRI or CT, and the pattern of bony destruction at CT. Bilateral involvement was present in three of six patients (50%). Lesions were most frequently located in the mastoid (n=8, 89%), followed by the petrous ridge (n=6, 67%), and the squamous portion (n=3, 33%). Seven (78%) lesions extended to the ipsilateral cavernous sinus (n=3), sphenoid bone (n=3), orbit (n=2), or epidural space (n=2). The signals of the soft tissue lesions were isointense in five cases (63%) on T1-weighted images and hyperintense in six (75%) at MRI, and homogeneous in five (71%) at CT. All lesions demonstrated bony destruction without periosteal reaction and five (71%) showed ill-defined destruction, with crossing sutures. Familiarity with findings of predominant mastoid involvement, isointense or isodense soft tissue lesions seen on T1-weighted images or at precontrast CT, with relatively homogeneous enhancement at CT, and irregular bony destruction with crossing sutures may be helpful in narrowing the diagnosis of temporal bone langerhans cell histiocytosis.

  17. MR and CT findings of temporal bone langerhans cell histiocytosis

    International Nuclear Information System (INIS)

    To describe the MRI and CT findings of temperal bone langerhans cell histiocytosis. The MRI (n=8) and CT (n=7) findings of nine lesions of temporal bone Langerhans cell histiocytosis in six children were retrospectively reviewed. Eight lesions were pathologically confirmed and one was clinically diagnosed. The findings were analyzed for bilaterality, location, lesion extent, signal intensity, the attenuation of soft tissue lesions seen at MRI or precontrast CT, enhancement pattern at MRI or CT, and the pattern of bony destruction at CT. Bilateral involvement was present in three of six patients (50%). Lesions were most frequently located in the mastoid (n=8, 89%), followed by the petrous ridge (n=6, 67%), and the squamous portion (n=3, 33%). Seven (78%) lesions extended to the ipsilateral cavernous sinus (n=3), sphenoid bone (n=3), orbit (n=2), or epidural space (n=2). The signals of the soft tissue lesions were isointense in five cases (63%) on T1-weighted images and hyperintense in six (75%) at MRI, and homogeneous in five (71%) at CT. All lesions demonstrated bony destruction without periosteal reaction and five (71%) showed ill-defined destruction, with crossing sutures. Familiarity with findings of predominant mastoid involvement, isointense or isodense soft tissue lesions seen on T1-weighted images or at precontrast CT, with relatively homogeneous enhancement at CT, and irregular bony destruction with crossing sutures may be helpful in narrowing the diagnosis of temporal bone langerhans cell histiocytosis

  18. An automatic approach for 3D registration of CT scans

    Science.gov (United States)

    Hu, Yang; Saber, Eli; Dianat, Sohail; Vantaram, Sreenath Rao; Abhyankar, Vishwas

    2012-03-01

    CT (Computed tomography) is a widely employed imaging modality in the medical field. Normally, a volume of CT scans is prescribed by a doctor when a specific region of the body (typically neck to groin) is suspected of being abnormal. The doctors are required to make professional diagnoses based upon the obtained datasets. In this paper, we propose an automatic registration algorithm that helps healthcare personnel to automatically align corresponding scans from 'Study' to 'Atlas'. The proposed algorithm is capable of aligning both 'Atlas' and 'Study' into the same resolution through 3D interpolation. After retrieving the scanned slice volume in the 'Study' and the corresponding volume in the original 'Atlas' dataset, a 3D cross correlation method is used to identify and register various body parts.

  19. CT and MRI preliminary study of langerhans' cell histiocytosis in temporal bone

    International Nuclear Information System (INIS)

    Objective: To study the CT and MRI features of Langerhans' cell histiocytosis affecting the temporal bone. Methods: Ten cases of Langerhans' cell histiocytosis of the temporal bone proved by clinical materials and pathology were retrospectively analyzed. CT was performed in all the 10 cases. MRI was also performed in 5 cases. Results: Temporal bone involvement presented as an isolated manifestation in 5 cases and was associated with lesions of other organs in the remaining 5 cases. External auditory canal and mastoid process were involved in 10 cases, squamous and petrous parts in 8 cases, and middle ear in 7 cases on CT scans. Destruction of ossicles and bony labyrinth were detected in 2 cases, respectively. CT showed massive lytic destruction in the affected region, associated with large soft tissue masses. The lesions had irregular border and well-defined margin without osteosclerosis in 8 cases. On MR imaging, external auditory canal and mastoid process were involved in 5 cases, squamous and petrous parts in 4 cases, middle ear in 3 cases, and membranous labyrinth in 1 case. The lesions were isointense or hypointense compared to brain on T1WI and hyperintense on T2WI in 5 cases. Postcontrast CT and MR imaging scans demonstrated marked enhancement. Conclusion: CT may clearly depict the bony lesions of the temporal bone in Langerhans' cell histiocytosis, and enhance the diagnostic accuracy to a great degree. MRI may effectively define the extent in the temporal bone, especially the intracranial invasion, and aid the selection of the optimal treatment procedure. Together with the two imaging modalities, the diagnosis, treatment, and follow-up would be greatly improved in patients with the temporal bone Langerhans' cell histiocytosis

  20. Module for applications of bone scan in cancer patients

    International Nuclear Information System (INIS)

    This paper reports the application of a software which enables the complete register of patient data, for delivering appropriate information in bone scan reports. Bone scan is a frequent study in Nuclear Medicine, which enables physicians to diagnose a primary bone cancer or metastases. The software was designed in order to complete data given by oncologists and constitutes an aid for the health team attending patients. (authors).

  1. CT assisted biomimetic artificial bone des

    Institute of Scientific and Technical Information of China (English)

    WANG Xian-gang; ZHANG Chao-zong; GUO Zhi-ping; TIAN Jie-mo

    2001-01-01

    @@ In the recent years, bioceramic materials have been widely used in the clinics. They are mainly fabricated as the substitution of human hard tissue, such as artificial bone and false tooth. As a medical implant, those that have similar structure to human bone have better biocompatibility and osteoinductional property. So it is necessary to design bone model close to human bone.

  2. Bone scintigraphy and osteo-articular tuberculosis in transplant patients: a study of 50 bone scans

    International Nuclear Information System (INIS)

    Bone scintigraphy with 99 m technecium labelled phosphorus compounds was achieved in 50 west Africans migrant workers in Paris. Bone and joint tuberculosis was assumed in 20 cases. In 5 of these 20 cases, bone scan, but not X-ray, showed abnormalities, and in 4, bone scan disclosed more localisations than X-rays. In 7 cases, yet, bone scan was normal, with major osteolytic X-rays lesions in 3 cases, minor in 2 cases, and isolated cold abcesses in two more cases: these means 7 false-negative results. Among the 30 other cases, 29 were considered as mechanical vertebral pathology, and 1 sacro-iliitis Brucellosis. Bone scan was normal in 28 cases the 2 others are unexplained false-positive. Although non-specific and not completely reliable, we think that bone-scanning is useful in bone-tuberculosis check-up, especially to obtain early diagnosis and detect multifocal localisations

  3. Bone scintigraphy and osteo-articular tuberculosis in transplant patients: a study of 50 bone scans

    Energy Technology Data Exchange (ETDEWEB)

    Coulaud, J.P.; Mechali, D.; Morau, G. (Hopital Claude-Bernard, Paris (France))

    1982-01-01

    Bone scintigraphy with 99 m technecium labelled phosphorus compounds was achieved in 50 west Africans migrant workers in Paris. Bone and joint tuberculosis was assumed in 20 cases. In 5 of these 20 cases, bone scan, but not X-ray, showed abnormalities, and in 4, bone scan disclosed more localisations than X-rays. In 7 cases, yet, bone scan was normal, with major osteolytic X-rays lesions in 3 cases, minor in 2 cases, and isolated cold abcesses in two more cases: these means 7 false-negative results. Among the 30 other cases, 29 were considered as mechanical vertebral pathology, and 1 sacro-iliitis Brucellosis. Bone scan was normal in 28 cases the 2 others are unexplained false-positive. Although non-specific and not completely reliable, we think that bone-scanning is useful in bone-tuberculosis check-up, especially to obtain early diagnosis and detect multifocal localisations.

  4. Pulmonary dynamic CT scan in COPD using EBCT

    International Nuclear Information System (INIS)

    Purpose: To evaluate the features of COPD in dynamic pulmonary CT scan. Materials and Methods: Thirty-two COPD patients, verified by clinical and pulmonary functional tests (PFT) were scanned by electron beam CT at end inspiration and expiration in continuous volume scan (CVS) mode. The control group consisted of 24 young healthy men, with normal plain chest film and PFT results. The lung was divided into three equal regions to measure and quantify the lung attenuation, volume and the ratio of pixels<-900 HU of the whole lung and different parts (pixel index, PI). Results: The CT value of the whole lung at end inspiration in COPD patients was -819 HU, similar to that of the control group -816 HU, but obviously lower at end expiration than control group (-751 HU VS -619 HU). The gradient between the two phases were 68 HU and 197 HU respectively. At end expiration phase, the lung volume of COPD patient decreased by 25.90%, only half of that of control group (54.90%). Twenty-eight (87.50%) of COPD patients had pixels lower than -900 HU with mean 10.76%. The number in control group was 4(16.67%) with mean 0.12%. Conclusion: The COPD patients have obvious air-trapping as compared with the normal group, which can be diagnosed and quantitated by pulmonary dynamic CT, which seems to be a promising method

  5. Polyphosphate bone scanning on non-malignant bone disease in children

    Energy Technology Data Exchange (ETDEWEB)

    Paul, D.J.; Gilday, D.L.

    1975-12-01

    The advent of /sup 99m/technetium phosphate bone scanning radiopharmaceuticals has opened new methods of investigation of pediatric bone diseases. In axial skeleton pain, suspected osteomyelitis, evaluation of vascular integrity and suspected but undetected fractures, the bone scan has proved to be a highly complementary study to the radiologic examination.

  6. Determination of prevalence of glenoid bony lesions after recurrent anterior shoulder dislocation using the 3-D CT scan

    OpenAIRE

    Guity, Mohamad Reza; Akhlaghpour, Shaharam; Yousefian, Reza

    2014-01-01

    Background: Glenoid bone damages consisting of anterior rim erosion and bony avulsion are very important in decision making for treatment of recurrent dislocation in shoulder joint. This study was aimed to determine the prevalence of these damages in patients with anterior recurrent shoulder dislocation. Methods: The study was a cross-sectional study evaluating patients with unstable shoulder joint. Glenoid bone damage was assessed using three dimensional (CT) scan implementing either glenoid...

  7. Brain CT scanning of children with purulent meningitis

    Energy Technology Data Exchange (ETDEWEB)

    Mishima, M.; Suzuki, M.; Nagata, M.; Kawamura, G.

    1986-12-01

    Nine of 21 children with purulent meningitis showed abnormal findings in brain CT when admitted. All of the abnormal group were less than 12 months of age, but 75 % of the normal group were more than 1 year old. The period of positive CRP was longer and the level of sugar in CSF was lower in abnormal group when compared with normal group. Because convulsion and EEG abnormalities were observed similarly in both groups, it may be difficult to determine the organic changes of the brain clinically. Brain CT scanning is recommended as soon as possible after the onset of purulent meningitis.

  8. Computed Tomography (CT) -- Sinuses

    Medline Plus

    Full Text Available ... air-filled spaces within the bones of the face surrounding the nasal cavity. CT scanning is painless, ... and blood vessels. A CT scan of the face produces images that also show a patient's paranasal ...

  9. Benign incidental findings of osteopoikilosis on Tc-99m MDP bone SPECT/CT: A case report and literature review.

    Science.gov (United States)

    Tsai, Szu-Ying; Wang, Shan-Ying; Shiau, Yu-Chien; Wu, Yen-Wen

    2016-06-01

    Osteopoikilosis is a benign but rare condition characterized by bone islands throughout the osseous tissue, which could be easily confused with bone metastasis. We present a case of a 37-year-old man presented to orthopedic outpatient clinic with right hip pain for 2 weeks. There were multiple, small punctate lesions scattered throughout the skeleton on radiograph. Subsequent Tc-99m methylene diphosphonate (MDP) bone scan with pelvic single-photon emission computed tomography (SPECT)/computed tomography (CT) showed multiple enostoses without abnormal focal MDP uptake. Therefore, clinical diagnosis was compatible with osteopoikilosis while bone metastasis was unlikely. The symptoms then improved by conservative treatments. Osteopoikilosis is usually an incidental finding on radiograph or CT, and a normal MDP confirmed the diagnosis by excluding bone metastasis. It is important for clinicians to recognize the specific image features to prevent further unnecessary interventions. In addition, bone SPECT/CT could also make the diagnosis in one step. PMID:27281099

  10. Facial bone scanning by emission tomography

    International Nuclear Information System (INIS)

    A single-photon emission tomographic system was used to study the normal anatomy of the facial bones and the usefulness of emission computed tomography in evaluating diseases of the bones of the face. The examination was performed following routine bone scintigraphy and took an additional 20 to 30 min. The anatomy of the facial bones was well defined, with clear separation of deep and superficial structuress. Early experience with tumor, infection, bone grafts, and postirradiation osteonecrosis indicates that useful added diagnostic information can be obtained by this method

  11. Can CT angiography rule out aneurysmal subarachnoid haemorrhage in CT scan-negative subarachnoid haemorrhage patients?

    Science.gov (United States)

    Lim, Lee Kai; Dowling, Richard J; Yan, Bernard; Mitchell, Peter J

    2014-01-01

    Current management guidelines for CT scan-negative subarachnoid haemorrhage (SAH) patients recommend cerebral digital subtraction angiography (DSA). We aimed to investigate the utility of CT angiography (CTA) as a substitute for DSA in these patients. We included patients who presented with SAH confirmed by spectrophotometric xanthochromia analysis of cerebrospinal fluid (CSF) whereby the CT scan was negative. Electronic records were reviewed to collect data on non-contrast CT scan, CTA and DSA results. Patients without DSA or with other explanations for CSF xanthochromia were excluded. Sixty-three patients with CT scan-negative SAH were included. The diagnosis of SAH was confirmed by CSF analysis. All 63 patients underwent both DSA and CTA. Using DSA as the benchmark, CTA demonstrated a negative predictive value, positive predictive value, sensitivity and specificity of 98%, 82%, 90% and 96%, respectively, for the detection of intracranial aneurysms. CTA correctly identified patients in whom there were no underlying aneurysms responsible for SAH, with one patient with suspected dissection referred for further evaluation using MRI and DSA. PMID:23954458

  12. CT scan findings of patients with Rett syndrome

    Energy Technology Data Exchange (ETDEWEB)

    Suzuki, Hisaharu; Takanashi, Aiko; Hirayama, Yoshito; Sakuragawa, Norio; Arima, Masataka; Tateno, Akihiko; Koide, Hiroyoshi.

    1989-05-01

    CT findings and clinical features were analyzed in 16 female patients with Rett syndrome, whose ages were between 4 and 20. Fifteen patients had microcrania. Twelve patients were able to stand and run; however, the remaining 4 patients had the only ability to sit. CT revealed an atrophy of the ponse and various degrees of dilatation in the Silvian fissure, frontal sulcus, and space between the cranium and the frontal polar lobe. An atrophy in the frontal lobe, cerebral cortex surrounding the Silvian fissure, and white matter directly below the cortex seemed to have an important role in the occurrence of this syndrome. There was, however, no definitive correlation between the degree of atrophy and both the patient's age and motor function. Serial CT scannings with clinical process are required. (Namekawa, K).

  13. Progression of CT scan findings in Rett syndrome

    Energy Technology Data Exchange (ETDEWEB)

    Suzuki, Hisaharu; Hirayama, Yoshito; Sakuragawa, Norio; Arima, Masataka (National Center of Neurology and Psychiatry, Kodaira, Tokyo (Japan))

    1989-07-01

    Progression of the lesions revealed by CT scan was observed in five girls with Rett syndrome. The most distinct and common finding was progressive dilatation of Sylvian fissures, frontal extracerebral space, interhemispheric fissure, and sulci mainly in frontal lobe. It may indicate progressive lesion in the frontal and the temporal lobes. In addition, dilatation of the anterior horns of the lateral ventricles and the third ventricle was noted in some cases. Brainstem and cerebellum were small at any age with some morphological development as the patients became elder. Neither malformations nor abnormalities in density were found in any case. It is concluded that the main lesion of Rett syndrome on CT scan is progressive and localized in the frontal and the temporal lobes. (author).

  14. Effects of breath holding CT scan during mid-expiration on PET/CT

    International Nuclear Information System (INIS)

    Objective: To study the effects of breath holding during mid-expiration of CT scan on PET/CT and SUV of lung. Methods: From September 2010 to December 2010, 200 patients including 120 males and 80 females (23-87 (55.01± 11.60) years), who underwent 18F-FDG PET/CT studies were included. Patients were randomly divided into 2 groups using random number table. In breath holding (BH) group (52 males, 48 females, age ranging from 29-83 (55.43±10.38) years), all underwent PET/CT studies with BH CT during mid-expiration.In free breath (FB) group (68 males, 32 females, age ranging from 23-87 (55.68± 12.72) years), all underwent PET/CT studies with FB CT. PET/CT images were analyzed by 1 senior technologist and 2 nuclear physicians. Analysis was carried out for the special registration of PET and CT, SUV of lung tissue on the bottom of lung and respiratory motion artifacts of lung on CT scanning. The diaphragmatic dome showed on the same layer of PET and CT was considered as well-registration between CT and PET. Two-sample t test, χ2 test and one-way analysis of variance were used to analyze data. Results: In BH group, 28% (28/100) of expiratory motion artifacts was observed, which was significantly lower than that of FB group (96%, 96/100; χ2=98.132, P<0.01). In BH group, 40% (80/200) was considered well-registration between CT and PET, which was significantly higher than that of FB group (30%, 60/200; χ2=4.396, P<0.05). There were 3 types of registration between CT and PET: location of diaphragm on CT higher than that on PET, matching between PET and CT, location of diaphragm on PET higher than that on CT. SUV in low lung tissue of these different types were increased one by one, with more significant difference found in BH group (SUVmax: 0.73±0.28, 1.00±0.29, 1.60±0.68; SUVmean: 0.59±0.23, 0.81±0.22, 1.33±0.34; F=21.93, 24.57, both P<0.01) than those in FB group (SUVmax: 0.84±0.36, 1.08±0.27, 1.16±0.24; SUVmean: 0.69±0.29, 0.85±0.20, 0.94±0.24; F=7.23, 6

  15. Bone scanning in the child and young adult. Pt. 2

    International Nuclear Information System (INIS)

    The sensitivity of the radionuclide bone scan in identifying osteoblastic reaction in bone and in detecting local alterations in blood flow is valuable in many benign diseases involving bone, particularly those which are more common in children and young adults, and in which early detection may be critical to future health. Bone scanning offers a simple, yet reliable means for establishing an early diagnosis, evaluating the extent of the disease, and assessing the therapeutic response in disorders resulting from infection, trauma or vascular insult. Useful information may also be obtained in disturbances of growth and development, and in congenital lesions. (orig.)

  16. Semi-automatic classification of textures in thoracic CT scans

    Science.gov (United States)

    Kockelkorn, Thessa T. J. P.; de Jong, Pim A.; Schaefer-Prokop, Cornelia M.; Wittenberg, Rianne; Tiehuis, Audrey M.; Gietema, Hester A.; Grutters, Jan C.; Viergever, Max A.; van Ginneken, Bram

    2016-08-01

    The textural patterns in the lung parenchyma, as visible on computed tomography (CT) scans, are essential to make a correct diagnosis in interstitial lung disease. We developed one automatic and two interactive protocols for classification of normal and seven types of abnormal lung textures. Lungs were segmented and subdivided into volumes of interest (VOIs) with homogeneous texture using a clustering approach. In the automatic protocol, VOIs were classified automatically by an extra-trees classifier that was trained using annotations of VOIs from other CT scans. In the interactive protocols, an observer iteratively trained an extra-trees classifier to distinguish the different textures, by correcting mistakes the classifier makes in a slice-by-slice manner. The difference between the two interactive methods was whether or not training data from previously annotated scans was used in classification of the first slice. The protocols were compared in terms of the percentages of VOIs that observers needed to relabel. Validation experiments were carried out using software that simulated observer behavior. In the automatic classification protocol, observers needed to relabel on average 58% of the VOIs. During interactive annotation without the use of previous training data, the average percentage of relabeled VOIs decreased from 64% for the first slice to 13% for the second half of the scan. Overall, 21% of the VOIs were relabeled. When previous training data was available, the average overall percentage of VOIs requiring relabeling was 20%, decreasing from 56% in the first slice to 13% in the second half of the scan.

  17. The clinical application of CT-guided percutaneous biopsy in the diagnosis of bone lesions

    International Nuclear Information System (INIS)

    Objective: To evaluate the clinical value of CT-guided percutaneous biopsy for bone lesions. Methods: Forty-Eight patients with different sited bone lesions had received the procedure of CT guided percutaneous biopsy from July 2003 to January 2005, including 34 cases only with complete clinical records. The procedure was carried out with patient lied on CT table and followed by localization scanning to demonstrate the best sites for puncture and biopsy route. 11-14 G bone puncture needle or 18 G trigger type biopsy needle was undertaken to penetrate into the lesion for obtaining specimens under local anesthesia and CT monitoring and in turn for fixation with 10% formalin to have pathologic examination. Results: The whole procedure finished within 20-40 minutes with adequate samples obtained for pathologic examination of all cases. Confirmed diagnosis was made in 30 cases with an accuracy of 91.2% and no correlative complications were found. Conclusions: The CT-guided percutaneous biopsy is safe and efficient for diagnosis of bone lesions, deserving to be extensively used. (authors)

  18. Plastinated fetus: 3D CT scan (VRT) evaluation

    OpenAIRE

    Shilpi Tiwari; Nandlal, B; N M Shama Sundar

    2012-01-01

    Objective: The intent of this study was to evaluate the effect of plastination on the morphology and structure of stored organs, to find out how much accuracy a plastinated specimen has, and to look into the changes that occurred because of plastination. Materials and Methods: A human fetus of gestational age 24 weeks was plastinated, and 3D CT scan evaluation of the fetus was done. Results: The results showed normal, well-defined, clearly identifiable organs, with no alteration in morp...

  19. CT scan of the spine for herniated discs

    Energy Technology Data Exchange (ETDEWEB)

    Gulati, A.N.; Weinstein, R.; Studdard, E.

    1981-10-01

    The high resolution conversion kit introduced for the EMI CT 5005 scanner has twice the spatial resolution of the usual scan mode and has proven to be quite useful in evaluation of the spinal canal. The present study was performed to determine the capability of the high resolution system to diagnose herniated lumbar disc without intrathecal contrast. HNP was diagnosed in 83% of the cases which had a positive myelogram, 70% of which had operation and all were proven positive.

  20. CT scanning for diagnosing blunt ureteral and ureteropelvic junction injuries

    Directory of Open Access Journals (Sweden)

    Chu Peter

    2008-02-01

    Full Text Available Abstract Background Blunt ureteral and ureteropelvic (UPJ injuries are extremely rare and very difficult to diagnose. Many of these injuries are missed by the initial trauma evaluation. Methods Trauma registry data was used to identify all blunt trauma patients with ureteral or UPJ injuries, from 1 April 2001 to 30 November 2006. Demographics, injury information and outcomes were determined. Chart review was then performed to record initial clinical and all CT findings. Results Eight patients had ureteral or UPJ injuries. Subtle findings such as perinephric stranding and hematomas, and low density retroperitoneal fluid were evident on all initial scans, and prompted delayed excretory scans in 7/8 cases. As a result, ureteral and UPJ injuries were diagnosed immediately for these seven patients. These findings were initially missed in the eighth patient because significant associated visceral findings mandated emergency laparotomy. All ureteral and UPJ injuries have completely healed except for the case with the delay in diagnosis. Conclusion Most blunt ureteral and UPJ injuries can be identified if delayed excretory CT scans are performed based on initial CT findings of perinephric stranding and hematomas, or the finding of low density retroperitoneal fluid.

  1. Colitis detection on abdominal CT scans by rich feature hierarchies

    Science.gov (United States)

    Liu, Jiamin; Lay, Nathan; Wei, Zhuoshi; Lu, Le; Kim, Lauren; Turkbey, Evrim; Summers, Ronald M.

    2016-03-01

    Colitis is inflammation of the colon due to neutropenia, inflammatory bowel disease (such as Crohn disease), infection and immune compromise. Colitis is often associated with thickening of the colon wall. The wall of a colon afflicted with colitis is much thicker than normal. For example, the mean wall thickness in Crohn disease is 11-13 mm compared to the wall of the normal colon that should measure less than 3 mm. Colitis can be debilitating or life threatening, and early detection is essential to initiate proper treatment. In this work, we apply high-capacity convolutional neural networks (CNNs) to bottom-up region proposals to detect potential colitis on CT scans. Our method first generates around 3000 category-independent region proposals for each slice of the input CT scan using selective search. Then, a fixed-length feature vector is extracted from each region proposal using a CNN. Finally, each region proposal is classified and assigned a confidence score with linear SVMs. We applied the detection method to 260 images from 26 CT scans of patients with colitis for evaluation. The detection system can achieve 0.85 sensitivity at 1 false positive per image.

  2. Can an abnormal CT scan be predicted from common symptoms after mild head injury in children?

    OpenAIRE

    Ashok Munivenkatappa; Akhil Deepika; Vasuki Prathyusha; Indira Devi; Dhaval Shukla

    2013-01-01

    Introduction: Children have non specific symptoms after mild head injury (MHI). It is difficult to define indication of CT scan among them. We aimed at identification of predictors of CT scan findings after MHI. Materials and Methods: Children aged ≤12 years with GCS 13-15 after head injury were retrospectively evaluated for their clinical and CT scan findings during January to March 2010. The variables used for detection of abnormal (positive) CT scan were age, gender, cause of injury (road ...

  3. Is the routine CT head scan justified for psychiatric patients? A prospective study.

    OpenAIRE

    Ananth, J.; Gamal, R; M. Miller; Wohl, M; Vandewater, S

    1993-01-01

    Thirty-four psychiatric patients, assessed for a physical illness that was missed during diagnosis, underwent a CT scan. After investigation, the diagnosis of 14 patients changed from a functional to an organic illness. In nine patients, the CT scan was reported to be abnormal, and yet only two were diagnosed as having an organic syndrome. In seven patients, the CT scan was normal but the patients had an undisputed organic brain syndrome. These findings indicate that the use of CT scans shoul...

  4. Bone quality evaluation at dental implant site using multislice CT, micro-CT, and cone beam CT

    NARCIS (Netherlands)

    A. Parsa; N. Ibrahim; B. Hassan; P. van der Stelt; D. Wismeijer

    2015-01-01

    Objectives The first purpose of this study was to analyze the correlation between bone volume fraction (BV/TV) and calibrated radiographic bone density Hounsfield units (HU) in human jaws, derived from micro-CT and multislice computed tomography (MSCT), respectively. The second aim was to assess the

  5. Pulmonary fat embolism induced intravenous injection of autologous bone marrow in rabbit: CT and pathologic correlation

    International Nuclear Information System (INIS)

    To evaluate the correlation between CT and pathologic findings of pulmonary fat embolism in rabbits. In 16 rabbits, pulmonary fat embolism was induced by intravenous injection of autologous bone marrow(mean 3.3 mL). Chest CT scans were obtained immediately(within 1 hour), and 1, 3, and 7 days after embolization. The rabbits were divided into four groups. Group 1 underwent CT scanning immediately after embolization, group 2 immediately and 1 day after embolization, group 3 immediately, 1 day and 3 days after embolization, group 4 immediately, 1 day, 3 days and 7 days after embolization. Pathologic specimens were obtained immediately after the last CT scan. The earliest CT findings of pulmonary fat embolism in rabbits were peripheral lung lucency(16/16, 100%), perivascular ground-glass(12/16, 75.0%) and enlargement of the central pulmonary artery(11/16, 68.8%). Pathologically, perivascular ground-glass opacity correlated with extensive perivascular alveolar congestion and enlargement of the central pulmonary artery correlated with perivascular connective tissue edema and reactive pulmonary arterial engorgement. Peripheral lung lucency was probably caused by embolic occlusion of the pulmonary artery and decreased perfusion and air trapping induced by arterial and bronchial spasm associated with hypoxia. CT scans obtained 1 and 3 days after embolization showed nodules and patchy ground-glass opacity and consolidation. Aggregation of nodules resulted in patch opacities. Pathologically, pulmonary nodules correlated with focal inflammation surrounding an artery and parenchymal opacity correlated with parenchymal consolidation and hemorrhagic edema. CT scans and pathologic specimens obtained 7 days after embolization showed improvement of parenchymal lung abnormalities. Pulmonary fat embolism in rabbits show CT and pathologic findings which vary with dynamic change. Typical earliest findings of pulmonary fat embolism were peripheral lung lucency, perivascular ground

  6. Using Micro-CT Derived Bone Microarchitecture to Analyze Bone Stiffness - A Case Study on Osteoporosis Rat Bone.

    Science.gov (United States)

    Wu, Yuchin; Adeeb, Samer; Doschak, Michael R

    2015-01-01

    Micro-computed tomography (Micro-CT) images can be used to quantitatively represent bone geometry through a range of computed attenuation-based parameters. Nonetheless, those parameters remain indirect indices of bone microarchitectural strength and require further computational tools to interpret bone structural stiffness and potential for mechanical failure. Finite element analysis (FEA) can be applied to measure trabecular bone stiffness and potentially predict the location of structural failure in preclinical animal models of osteoporosis, although that procedure from image segmentation of Micro-CT derived bone geometry to FEA is often challenging and computationally expensive, resulting in failure of the model to build. Notably, the selection of resolution and threshold for bone segmentation are key steps that greatly affect computational complexity and validity. In the following study, we evaluated an approach whereby Micro-CT derived grayscale attenuation and segmentation data guided the selection of trabecular bone for analysis by FEA. We further correlated those FEA results to both two- and three-dimensional bone microarchitecture from sham and ovariectomized (OVX) rats (n = 10/group). A virtual cylinder of vertebral trabecular bone 40% in length from the caudal side was selected for FEA, because Micro-CT based image analysis indicated the largest differences in microarchitecture between the two groups resided there. Bone stiffness was calculated using FEA and statistically correlated with the three-dimensional values of bone volume/tissue volume, bone mineral density, fractal dimension, trabecular separation, and trabecular bone pattern factor. Our method simplified the process for the assessment of trabecular bone stiffness by FEA from Micro-CT images and highlighted the importance of bone microarchitecture in conferring significantly increased bone quality capable of resisting failure due to increased mechanical loading. PMID:26042089

  7. Quantification of the accuracy of MRI generated 3D models of long bones compared to CT generated 3D models.

    Science.gov (United States)

    Rathnayaka, Kanchana; Momot, Konstantin I; Noser, Hansrudi; Volp, Andrew; Schuetz, Michael A; Sahama, Tony; Schmutz, Beat

    2012-04-01

    Orthopaedic fracture fixation implants are increasingly being designed using accurate 3D models of long bones based on computer tomography (CT). Unlike CT, magnetic resonance imaging (MRI) does not involve ionising radiation and is therefore a desirable alternative to CT. This study aims to quantify the accuracy of MRI-based 3D models compared to CT-based 3D models of long bones. The femora of five intact cadaver ovine limbs were scanned using a 1.5 T MRI and a CT scanner. Image segmentation of CT and MRI data was performed using a multi-threshold segmentation method. Reference models were generated by digitising the bone surfaces free of soft tissue with a mechanical contact scanner. The MRI- and CT-derived models were validated against the reference models. The results demonstrated that the CT-based models contained an average error of 0.15 mm while the MRI-based models contained an average error of 0.23 mm. Statistical validation shows that there are no significant differences between 3D models based on CT and MRI data. These results indicate that the geometric accuracy of MRI based 3D models was comparable to that of CT-based models and therefore MRI is a potential alternative to CT for generation of 3D models with high geometric accuracy.

  8. Bone scanning as a routine examination of patients with mammary carcinoma; a critical consideration. [Preoperative scanning

    Energy Technology Data Exchange (ETDEWEB)

    Heslinga, J.M.; Pauwels, E.K.J.; Zwaveling, A. (Rijksuniversiteit Leiden (Netherlands). Academisch Ziekenhuis)

    1982-06-05

    The usefulness of bone scanning as a routine examination was evaluated in 136 female patients with mammary carcinoma of whom 81 were staged as Columbia A and 55 as Columbia B/C. The preoperative bone scanning was positive in only 4 patients (2.9%). Consequently, bone scanning is no longer performed in the authors clinic for the preoperative detection of skeletal metastases. Bone scanning as a routine examination at 6-month intervals does not appear to be useful for the first 4 years of the follow-up, either. Most of the patients with a positive bone scan displayed other signs of skeletal metastases at the same time, such as ostealgia and a raised serum alkaline phosphatase level. Further increase of the frequency of bone scanning during the follow-up period would increase the costs considerably, almost prohibitively, even apart from the question whether such a measure might indeed significantly influence the patient's prognosis. The authors conclude that bone scanning should only be performed on the basis of the anamnesis, physical and laboratory findings, both prior to operation and during the follow-up period.

  9. Evaluation of bone substitute materials: comparison of flat-panel based volume CT to conventional multidetector CT.

    Science.gov (United States)

    Sauerbier, Sebastian; Duttenhoefer, Fabian; Sachlos, Elefterios; Haberstroh, Jörg; Scheifele, Christian; Wrbas, Karl-Thomas; Voss, Pit Jacob; Veigel, Egle; Smedek, Jörg; Ganter, Philip; Tuna, Taskin; Gutwald, Ralf; Palmowski, Moritz

    2013-10-01

    Over the last decade tissue engineering has emerged as a key factor in bone regeneration within the field of cranio-maxillofacial surgery. Despite this in vivo analysis of tissue-engineered-constructs to monitor bone rehabilitation are difficult to conduct. Novel high-resolving flat-panel based volume CTs (fp-VCT) are increasingly used for imaging bone structures. This study compares the potential value of novel fp-VCT with conventional multidetector CT (MDCT) based on a sheep sinus floor elevation model. Calcium-hydroxyapatite reinforced collagen scaffolds were populated with autologous osteoblasts and implanted into sheep maxillary sinus. After 8, 16 and 24 weeks MDCT and fp-VCT scans were performed to investigate the volume of the augmented area; densities of cancellous and compact bone were assessed as comparative values. fp-VCT imaging resulted in higher spatial resolution, which was advantageous when separating closely related anatomical structures (i.e. trabecular and compact bone, biomaterials). Fp-VCT facilitated imaging of alterations occurring in test specimens over time. fp-VCTs therefore displayed high volume coverage, dynamic imaging potential and superior performance when investigating superfine bone structures and bone remodelling of biomaterials. Thus, fp-VCTs may be a suitable instrument for intraoperative imaging and future in vivo tissue-engineering studies.

  10. Evaluating soft tissue simulation in maxillofacial surgery using pre and post-operative CT scan

    CERN Document Server

    Chabanas, M; Chouly, F; Boutault, F; Payan, Y; Chabanas, Matthieu; Marecaux, Christophe; Chouly, Franz; Boutault, Franck; Payan, Yohan

    2004-01-01

    One of the most important issue in soft tissue modeling is to assess the quality of the simulations. A validation protocol is presented based on two CT scans of the patient acquired before and after cranio-maxillofacial surgery. The actual bones repositioning realized during the intervention are accurately measured and reproduced. A evaluation of the soft tissue deformation is then computed using a finite element model of the face. The simulations are therefore compared, qualitatively and quantitatively, with the actual outcome of the surgery. This protocol enable to rigorously evaluate different modeling methods, and to assess the clinical relevance of soft tissue simulation in maxillofacial surgery.

  11. Incidental Detection of Subcutaneous Myopericytoma of Trunk on FDG PET/CT and Bone Scintigraphy for Imaging of Colon Cancer.

    Science.gov (United States)

    Demir, Selin Soyluoglu; Sarikaya, Ali; Aktas, Gul Ege; Oz Puyan, Fulya

    2016-08-01

    Myopericytoma is a rare type of unusual soft tissue tumor with perivascular myoid differentiation. A 53-year-old man with the diagnosis of colon cancer was referred to Tc-MDP bone scan and F-FDG PET/CT for staging. A subcutaneous mass located in right lower back with heterogeneous FDG uptake was detected on PET/CT. There was increased osteoblastic activity on MDP bone scan in the same region. Mass was resected and subsequently confirmed as myopericytoma by histopathology. PMID:27124684

  12. Bone Forming Potential of An-Organic Bovine Bone Graft: A Cone Beam CT study

    OpenAIRE

    Uzbek, Usman Haider; Rahman, Shaifulizan Ab; Alam, Mohammad Khursheed; gillani, syed wasif

    2014-01-01

    Purpose: An-organic bovine bone graft is a xenograft with the potential of bone formation. The aim of this study was to evaluate the bone density using cone beam computed tomography scans around functional endosseous implant in the region of both augmented maxillary sinus with the an-organic bovine bone graft and the alveolar bone over which the graft was placed to provide space for the implants.

  13. An assessment of pulmonary emphysema in smokers using CT scan

    International Nuclear Information System (INIS)

    We assessed the relationship between PE and smoking in 639 cases (411 males and 228 females with age ranged 21-86 years) who underwent CT scans during the period, from December 1997 to December 1998, under suspicion of respiratory disease on chest radiograph or some respiratory complaints. PE was diagnosed by the existence of low attenuation areas in CT scan and not by pulmonary function tests. CT was performed with 10 mm collimation in a standard algorithm. PE, regardless of the grade, was seen: in 189 out of 348 (54.3%) cases in male smokers and in only 2 out of 63 (3.2%) cases in male non-smokers; and in 5 out of 25 (20.0%) female smokers and in 4 out of 203 (2.0%) female non-smokers. PE was observed in more than half of male smokers. High incidence of PE was also observed in even younger generation, and its severity progresses with advancing age and increasing smoking index. (author)

  14. Tumor markers and bone scan in breast cancer patients

    International Nuclear Information System (INIS)

    Full text: The objective of this study was to compare the levels of CA15-3 and CEA with the bone scan findings in patients with breast cancer. Retrospective analysis of 76 bone scans from 61 patients diagnosed with breast cancer in the last 5 years was performed by two nuclear medicine specialists. All bone scans were performed after surgical treatment of the disease. Patients with loco-regional residual disease or distant metastases in the liver, lung or the brain were excluded from the study. According to the bone scan the patients were divided in 5 groups: normal bone scan (N), equivocal bone scan (E), single metastasis (1MS), three metastases (3MS) and multiple metastases (MMS). Tumor markers were determined within a month before or after the bone scan was performed. Cut-off value for CA 15-3 was 35 U/ml, and for CEA 3 ng/ml. Statistical analysis was performed using descriptive statistic and Kolmogorov-Smirnov test. Bone metastases were revealed in 38% of the patients referred for bone scintigraphy out of which 26% had MMS, 7.8% had single MS and 4% had 3MS. The results of 6.5% of the patients were determined as equivocal. The values of CA15-3 were higher in all patient groups compared with the group that had normal bone scan, but this difference reached statistical significance only in groups with 3MS and MMS (p < 0.01). The values of CEA were significantly higher only in patients with multiple metastases when compared with group N (p < 0.01). Values higher than cut-off value for CA 15-3 was found in 9 patients out of 42 in the group with normal bone scan. The highest value of CA 15-3 in this group was 47 U/ml. Only one patient in this group showed elevated levels for CEA. Three patients in the group with single metastasis had normal CA 15-3, while CEA was elevated only in one patient. All patients in the group with 3MS had elevated levels of CA 15-3 while CEA was in the normal range. All patients with MMS had elevated CA 15-3 values while CEA was elevated in

  15. Analysis of the acetabulum by CT scan in Japanese with osteoarthritis of the hip

    Energy Technology Data Exchange (ETDEWEB)

    Ishibashi, Masanori [Keio Univ., Tokyo (Japan). School of Medicine

    1997-11-01

    The morphology of the acetabulum was analyzed by CT scan in 66 Japanese patients with osteoarthritis of the hip mainly following congenital dislocation or dysplasia. The CT scan data was analyzed to standardize the pelvic inclination in all directions. In these patients, the acetabular floor had thickened and the acetabulum was located in the anterolateral portion. The bilateral difference in the acetabular anteversion angle was not different between patients and normal individuals, but the acetabular sector angle in patients was smaller than in the normal subjects. As the stage of osteoarthritis of the hip advanced, the thickness of the acetabular floor in the center and posterior portions and the anterior sector angle increased, and the lateralization of the acetabulum advanced, but the anteversion angle decreased. A bone-forming change is characteristic of the anterior acetabulum and acetabular fossa in the center and posterior portions in Japanese patients with osteoarthritis of the hip. In comparison with data obtained by standard radiography, these changes detected by CT scan corresponded to an increase of the width of a tear drop, the lateralization of the femoral head and the lack of the support of the femoral head from the acetabulum. (author)

  16. Analysis of the acetabulum by CT scan in Japanese with osteoarthritis of the hip

    International Nuclear Information System (INIS)

    The morphology of the acetabulum was analyzed by CT scan in 66 Japanese patients with osteoarthritis of the hip mainly following congenital dislocation or dysplasia. The CT scan data was analyzed to standardize the pelvic inclination in all directions. In these patients, the acetabular floor had thickened and the acetabulum was located in the anterolateral portion. The bilateral difference in the acetabular anteversion angle was not different between patients and normal individuals, but the acetabular sector angle in patients was smaller than in the normal subjects. As the stage of osteoarthritis of the hip advanced, the thickness of the acetabular floor in the center and posterior portions and the anterior sector angle increased, and the lateralization of the acetabulum advanced, but the anteversion angle decreased. A bone-forming change is characteristic of the anterior acetabulum and acetabular fossa in the center and posterior portions in Japanese patients with osteoarthritis of the hip. In comparison with data obtained by standard radiography, these changes detected by CT scan corresponded to an increase of the width of a tear drop, the lateralization of the femoral head and the lack of the support of the femoral head from the acetabulum. (author)

  17. Using Micro-CT Derived Bone Microarchitecture to Analyze Bone Stiffness - A Case Study on Osteoporosis Rat Bone

    Directory of Open Access Journals (Sweden)

    Yuchin eWu

    2015-05-01

    Full Text Available Micro-computed tomography images can be used to quantitatively represent bone geometry through a range of computed attenuation-based parameters. Nonetheless, those parameters remain indirect indices of bone micro-architectural strength and require further computational tools to interpret bone structural stiffness and potential for mechanical failure. Finite element analysis (FEA can be applied to measure trabecular bone stiffness and potentially predict the location of structural failure in preclinical animal models of osteoporosis, although that procedure from image segmentation of micro-CT derived bone geometry to FEA is often challenging and computationally expensive, resulting in failure of the model to build. Notably, the selection of resolution and threshold for bone segmentation are key steps that greatly affect computational complexity and validity. In the following study, we evaluated an approach whereby Micro-CT derived greyscale attenuation and segmentation data guided the selection of trabecular bone for analysis by FEA. We further correlated those FEA results to both two and three dimensional bone microarchitecture from sham and ovariectomized (OVX rats (n=10/group. A virtual cylinder of vertebral trabecular bone 40% in length from the caudal side was selected for FEA because micro-CT based image analysis indicated the largest differences in microarchitecture between the two groups resided there. Bone stiffness was calculated using FEA and statistically correlated with the three dimensional values of bone volume/tissue volume, bone mineral density, fractal dimension, trabecular separation and trabecular bone pattern factor. Our method simplified the process for the assessment of trabecular bone stiffness by FEA from Micro-CT images and highlighted the importance of bone microarchitecture in conferring significantly increased bone quality capable of resisting failure due to increased mechanical loading.

  18. Computed tomographic (CT) scans in cerebral palsy (CP)

    Energy Technology Data Exchange (ETDEWEB)

    Kolawole, T.M.; Patel, P.J. (King Saud Univ., Riyadh (Saudi Arabia). Dept. of Radiology); Mahdi, A.H. (King Saud Univ., Riyadh (Saudi Arabia). Dept. of Paediatrics)

    1989-11-01

    The CT findings in 120 cerebral palsied children are analysed. The 72.5% positive findings are correlated with the clinical types, as well as the aetiological basis for the cerebral palsy. The spastic type, 83.3% of the total number of children, had the highest positive findings. The yield was increased in children with seizures (91.3%) and those in the postnatal group (90%), as well as those with birth trauma and neonatal asphyxia (94%). The findings were those of atrophy in 30.8%, hydrocephalus, in 10%, infarct in 11.6%, porencephaly in 8.3% and others. The atropic changes and their patterns are explained. Treatable lesions, such as tumour, hydrocephalus, subdural haematoma, porencephaly and hygroma were identified in 22.5% of cases. It is concluded that CT scan is definitely efficacious in the management of cerebral palsied children. (orig.).

  19. Penentuan Nilai Noise Berdasarkan Slice Thickness Pada Citra CT Scan

    OpenAIRE

    Sihombing, Hediana

    2015-01-01

    Noise measurements have been carried out with changes in thick slices CT Scan image by selecting the ROI on a water phantom objects. The method used in the measurement of noise values ranging from 1 mm, 2 mm, 3 mm, 4 mm, 5 mm, 6 mm, 7 mm, 8 mm, 9 mm, and 10 mm and eksposi factor of 100 kV and 500 mAs. The results obtained are 6.32 HU; 5:14 HU; 3.86 HU; HU 3:48; HU 3:14; 2.94 HU; 2.78 HU; 2.52 HU; HU HU 2:44 and 2:38. The thicker slices diminishing the noise then the resulting CT images wer...

  20. Computed tomographic (CT) scans in cerebral palsy (CP)

    International Nuclear Information System (INIS)

    The CT findings in 120 cerebral palsied children are analysed. The 72.5% positive findings are correlated with the clinical types, as well as the aetiological basis for the cerebral palsy. The spastic type, 83.3% of the total number of children, had the highest positive findings. The yield was increased in children with seizures (91.3%) and those in the postnatal group (90%), as well as those with birth trauma and neonatal asphyxia (94%). The findings were those of atrophy in 30.8%, hydrocephalus, in 10%, infarct in 11.6%, porencephaly in 8.3% and others. The atropic changes and their patterns are explained. Treatable lesions, such as tumour, hydrocephalus, subdural haematoma, porencephaly and hygroma were identified in 22.5% of cases. It is concluded that CT scan is definitely efficacious in the management of cerebral palsied children. (orig.)

  1. Juvenile Psammomatoid Ossifying Fibroma: Findings on Bone Scan.

    Science.gov (United States)

    Cárdenas-Perilla, Rodrigo; Santamaria, Consuelo; Muñoz-Acosta, Juan Manuel

    2016-09-01

    Juvenile psammomatoid ossifying fibroma is a rare bone-forming tumor seen in craniofacial bones, which affects mainly young patients. We report scintigraphic and SPECT/CT findings of 2 patients diagnosed with this disease. One patient presented with suspicion of fibrous dysplasia and the other with suspected malignancy in the setting of a rapidly growing mass. Both cases highlight the importance of recognizing this type of tumor in young patients with abnormal uptake in paranasal bones and sinuses within the range of potential differential diagnoses including sarcomas, fibrous dysplasia, and odontogenic tumors. PMID:27405032

  2. Accuracy of bone SPECT/CT for identifying hardware loosening in patients who underwent lumbar fusion with pedicle screws

    Energy Technology Data Exchange (ETDEWEB)

    Hudyana, Hendrah; Maes, Alex [AZ Groeninge, Department of Nuclear Medicine, Kortrijk (Belgium); University Hospital Leuven, Department of Morphology and Medical Imaging, Leuven (Belgium); Vandenberghe, Thierry; Fidlers, Luc [AZ Groeninge, Department of Neurosurgery, Kortrijk (Belgium); Sathekge, Mike [University of Pretoria, Department of Nuclear Medicine, Pretoria (South Africa); Nicolai, Daniel [AZ Groeninge, Department of Nuclear Medicine, Kortrijk (Belgium); Wiele, Christophe van de [AZ Groeninge, Department of Nuclear Medicine, Kortrijk (Belgium); University Ghent, Department of Radiology and Nuclear Medicine, Ghent (Belgium)

    2016-02-15

    The aim of this retrospective study was to evaluate the accuracy of bone SPECT (single photon emission computed tomography)/CT (computed tomography) in diagnosing loosening of fixation material in patients with recurrent or persistent back pain that underwent lumbar arthrodesis with pedicle screws using surgery and clinical follow-up as gold standard A total of 48 patients (median age 49 years, range 21-81 years; 17 men) who had undergone lumbar spinal arthrodesis were included in this retrospective analysis. SPECT/CT results were compared to the gold standard of surgical evaluation or clinical follow-up. Positive SPECT/CT results were considered true positives if findings were confirmed by surgery or if clinical and other examinations were completely consistent with the positive SPECT/CT finding. They were considered false positives if surgical evaluation did not find any loose pedicle screws or if symptoms subsided with non-surgical therapy. Negative SPECT/CT scans were considered true negatives if symptoms either improved without surgical intervention or remained stable over a minimum follow-up period of 6 months. Negative SPECT/CT scans were determined to be false negatives if surgery was still required and loosening of material was found. The median length of time from primary surgery to bone SPECT/CT referral was 29.5 months (range 12-192 months). Median follow-up was 18 months (range 6-57) for subjects who did not undergo surgery. Thirteen of the 48 patients were found to be positive for loosening on bone SPECT/CT. Surgical evaluation (8 patients) and clinical follow-up (5 patients) showed that bone SPECT/CT correctly predicted loosening in 9 of 13 patients, while it falsely diagnosed loosening in 4 patients. Of 35 negative bone SPECT/CT scans, 12 were surgically confirmed. In 18 patients, bone SPECT/CT revealed lesions that could provide an alternative explanation for the symptoms of pain (active facet degeneration in 14 patients, and disc and sacroiliac

  3. Does aspiration of bones and joints affect results of later bone scanning

    International Nuclear Information System (INIS)

    To determine the effect, if any, of needle aspiration on /sup 99m/Tc bone scanning, three different areas of 15 dogs were first aspirated and then imaged with technetium bone scintigraphy. The hip joint was aspirated, the distal femoral metaphysis was drilled and aspirated, and the tibial periosteum was scraped with an 18- or 20-gauge needle. Varying amounts of trauma were inflicted to simulate varying difficulties at aspiration. /sup 99m/Tc bone scans were obtained from 5 h to 10 days later. There was no evidence of focal technetium uptake after any hip joint aspiration. This was consistent regardless of the amount of trauma inflicted or the time from aspiration to bone scanning. Metaphyseal cortical drilling and tibial periosteal scraping occasionally caused some focal uptake when scanning was delayed greater than 2 days. When osteomyelitis or pyarthrosis is clinically suspected, joint aspiration can be performed without fear of producing a false- positive bone scan

  4. Bone SPECT and CT fusion imaging in pediatric neuroblastoma

    International Nuclear Information System (INIS)

    Objective: To evaluate the diagnostic performance of bone SPECT and CT fusion imaging in bone metastases from pediatric neuroblastoma. Methods: Twenty-four pediatric patients with neuroblastoma were included in this retrospective study. All patients underwent planar imaging and SPECT integrated with CT. Lesion visibility,diagnostic certainty and diagnostic performance were evaluated with Kolmogorov-Smirnov test and χ2 test. Results: Lesion visibility of SPECT alone, SPECT integrated with CT were significantly better than that of planar imaging (both H=69.000, P<0.05). SPECT and CT fusion imaging, SPECT alone both detected five more bone lesions than planar bone imaging (77 vs 72). The diagnostic accuracy of SPECT imaging (62.34%, 48/77) was significantly higher than that of planar imaging (45.45%, 35/77; χ2=4.416, P<0.05). The sensitivity,specificity and accuracy of SPECT and CT fusion imaging for diagnosing malignant bone lesions were significantly higher than those of planar imaging: 82.35% (42/51) vs 53.19% (25/47), 88.46% (23/26) vs 40.00% (10/25), 84.42% (65/77) vs 45.45% (35/77; χ2=12.571, 14.016, 25.667, all P<0.01). The diagnostic specificity and accuracy of SPECT and CT fusion imaging were significantly higher than those of SPECT alone (53.85%, 14/26; 62.34%, 48/77) (χ2=7.589, 9.606, both P<0.01). However, there was no significant difference of sensitivity between the two methods (χ2=2.942, P>0.05). Diagnostic certainty by SPECT and CT fusion imaging was significantly higher than that by SPECT alone (H=28.000, P<0.05) and by planar imaging (H=21.000, P<0.05). Conclusion: SPECT and CT fusion imaging can detect more bone lesions in patients with pediatric neuroblastoma. It is helpful for diagnosing bone metastases from pediatric neuroblastoma. (authors)

  5. Evaluation of normal brain CT scan in Koreans

    International Nuclear Information System (INIS)

    The safety of procedure combined with wealth of information have resulted in rapid acceptance of CT as a practical and reliable neurodiagnostic technique. To understand the alternation in tissue density and associated displacement and distortion caused by pathologic lesion in CT, it is necessary to have clear understanding of normal anatomical landmark. For the purpose of establishing normartive criteria in Koreans for comparative diagnosis, 500 normal CT scan without neurologic sign were studied. The brief results are follows; 1. Among many ventricular index measured for lateral ventricle, the bifrontal CVI is more sensitive and easily determined. Ventricular size increased with age, especially after 6th decade but no difference with sex. 2. Mean width of third ventricle is 5mm( ± 0.3), more wider in male (male; 5.2mm, female; 4.5mm) and increased with age. 3. Mean width of fourth ventricle is 13mm( ± 1.3), without difference in age and sex. The shape of ventricle is variable form of triangle. The position of ventricle relative to Twining's line can be determined, so ratio of distance from tuberculum sellae to center of fourth ventricle to Twining's line is between 0.46-0.52. 4. Suprasellar cistern is visible in 89.7% of scan and shape of cistern is found to be pentagonal (73.3%), hexagonal (23.0%) and tetragonal (3.7%). 5. Choroid plexus can be identified in 90% and asymetrical in 4%. 45% of identified choroid plexus can be visible on scan without contrast enhancement, and more frequently visible in older age

  6. Evaluation of normal brain CT scan in Korean

    International Nuclear Information System (INIS)

    The safety of procedure combined with wealth of information have resulted in rapid acceptance of CT as a practical and reliable neurodignostic technique. To understand the alternation in tissue density and associated displacement and distortion caused by pathologic lesion in CT, it is necessary to have clear understanding of normal anatomical landmark. For the purpose of establishing normative criteria in Korean for comparative diagnosis, 500 normal CT scan without neurologic sign were studied. The brief results are follows; 1. Among many ventricular index measured for lateral ventricle, the bifrontal CVI is more sensitive and easily determined. Ventricular size increased with age, especially after 6th decade but no difference with sex. 2. Mean width of third ventricle is 5 mm (± 0.3), more wider in male (male; 5.2 mm, female; 4.5 mm) and increased with age. 2. Mean width of fourth ventricle is 13 mm (± 1.3), without difference in age and sex. The shape of ventricle is variable form of triangle. The position of ventricle relative to Twining's line can be determined, so ratio of distance from tuberculum sellae to center of fourth ventricle to Twining's line is between 0.46-0.52. 4. Suprasellar cistern is visible in 89.7% of scan and shape of cistern is found to be pentagonal (73.3%), hexagonal (23.0%) and tetragonal (3.7%). 5. Choroid plexus can be identified in 90% and asymmetrical in 4%. 45% of identified choroid plexus can be visible on scan without contrast enhancement, and more frequently visible in older age

  7. The Usefulness of Bone Scan in Electric Burns

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Tae Hyung; So, Yong Seon; Kweon, Ki Hyeon; Han, Sang Woong; Kim, Seok Hwan; Kim, Jong Soon; Han, Seung Soo [Hanil Hospital, Seoul (Korea, Republic of)

    1996-03-15

    Bone scan is known to be an effective tool for observing the state of soft tissues and bones of electric burn patients. It is also used for observing the progress of patients after debridement or skin graft as well as determining to amputate specific body parts. To evaluate bone scan's role in electric burn, we analyzed bone scan 37 patients with electric burn. Among the 37 patients, 8 of 37 were injured in low voltage and 29 of them in high voltage. 27 patients received the electrical input through the hand, 6 through the scalp, 2 through the shoulder, 1 through the left chest wall and 1 through the left inguinal area. Among 29 patients received high voltage, 22 patients had the electrical output through the foot, 3 through the hand, 2 through the shoulder, 1 through the buttock and 1 through the left chest wall. Bone scans revealed cellulitis in 37 patients with 47 sites, osteomyelitis in 15 patients with 15 sites and bone defects in 4 patients with 4 sites. In 4 patients with skin graft or skin flap, follow up bone scan showed improvements of bony uptake in preoperatively bony defect area and all of them were healed without complication There were 2 cases in which uptake increased in the myocardium, 1 in the liver and 6 in the kidney, however, scrum calcium level, EKG, cardiac enzyme, liver and renal function tests were normal. In conclusion, bone scans are helpful in the assessment of injury sites after electrical insult and in differential diagnosis of cellulitis and osteomyelitis. It is also useful tool of assessment after skin graft or skin flap, however, it should be further evaluated about internal organ damage.

  8. The Usefulness of Bone Scan in Electric Burns

    International Nuclear Information System (INIS)

    Bone scan is known to be an effective tool for observing the state of soft tissues and bones of electric burn patients. It is also used for observing the progress of patients after debridement or skin graft as well as determining to amputate specific body parts. To evaluate bone scan's role in electric burn, we analyzed bone scan 37 patients with electric burn. Among the 37 patients, 8 of 37 were injured in low voltage and 29 of them in high voltage. 27 patients received the electrical input through the hand, 6 through the scalp, 2 through the shoulder, 1 through the left chest wall and 1 through the left inguinal area. Among 29 patients received high voltage, 22 patients had the electrical output through the foot, 3 through the hand, 2 through the shoulder, 1 through the buttock and 1 through the left chest wall. Bone scans revealed cellulitis in 37 patients with 47 sites, osteomyelitis in 15 patients with 15 sites and bone defects in 4 patients with 4 sites. In 4 patients with skin graft or skin flap, follow up bone scan showed improvements of bony uptake in preoperatively bony defect area and all of them were healed without complication There were 2 cases in which uptake increased in the myocardium, 1 in the liver and 6 in the kidney, however, scrum calcium level, EKG, cardiac enzyme, liver and renal function tests were normal. In conclusion, bone scans are helpful in the assessment of injury sites after electrical insult and in differential diagnosis of cellulitis and osteomyelitis. It is also useful tool of assessment after skin graft or skin flap, however, it should be further evaluated about internal organ damage.

  9. MicroCT Bone Densitometry: Context Sensitivity, Beam Hardening Correction and the Effect of Surrounding Media

    Directory of Open Access Journals (Sweden)

    Philip L. Salmon

    2014-12-01

    Full Text Available The context-sensitivity of microCT bone densitometry due to beam hardening artefacts was assessed. Bones and teeth are scanned with varying thickness of surrounding media (water, alcohol, biological tissue and it is important to understand how this affects reconstructed attenuation (“density” of the mineralized tissue. Aluminium tubes and rods with thickness 0.127mm–5mm were scanned both in air or surrounded by up to 2cm of water. Scans were performed with different energy filters and degrees of software beam hardening correction (BHC. Also tested were the effects of signal-to-noise ratio, magnification and truncation. The thickness of an aluminium tube significantly affected its mean reconstructed attenuation. This effect of thickness could be reduced substantially by BHC for scans in air, but not for scans in water. Varying thickness of surrounding water also changed the mean attenuation of an aluminium tube. This artefact could be almost eliminated by an optimal BHC value. The “cupping” artefact of heterogeneous attenuation (elevated at outer surfaces could be corrected if aluminium was scanned in air, but in water BHC was much less effective. Scan truncation, changes to magnification and signal-to-noise ratio also caused artificial changes to measured attenuation. Measurement of bone mineral density by microCT is highly context sensitive. A surrounding layer of liquid or biological tissue reduces the ability of software BHC to remove bone density artefacts. Sample thickness, truncation, magnification and signal to noise ratio also affect reconstructed attenuation. Thus it is important for densitometry that sample and calibration phantom dimensions and mounting materials are standardised.

  10. Effects of CT image segmentation methods on the accuracy of long bone 3D reconstructions.

    Science.gov (United States)

    Rathnayaka, Kanchana; Sahama, Tony; Schuetz, Michael A; Schmutz, Beat

    2011-03-01

    An accurate and accessible image segmentation method is in high demand for generating 3D bone models from CT scan data, as such models are required in many areas of medical research. Even though numerous sophisticated segmentation methods have been published over the years, most of them are not readily available to the general research community. Therefore, this study aimed to quantify the accuracy of three popular image segmentation methods, two implementations of intensity thresholding and Canny edge detection, for generating 3D models of long bones. In order to reduce user dependent errors associated with visually selecting a threshold value, we present a new approach of selecting an appropriate threshold value based on the Canny filter. A mechanical contact scanner in conjunction with a microCT scanner was utilised to generate the reference models for validating the 3D bone models generated from CT data of five intact ovine hind limbs. When the overall accuracy of the bone model is considered, the three investigated segmentation methods generated comparable results with mean errors in the range of 0.18-0.24 mm. However, for the bone diaphysis, Canny edge detection and Canny filter based thresholding generated 3D models with a significantly higher accuracy compared to those generated through visually selected thresholds. This study demonstrates that 3D models with sub-voxel accuracy can be generated utilising relatively simple segmentation methods that are available to the general research community.

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

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Su San; Choi, Eun Kyung; Yi, Byong Yong [Asan Medical Center, College of Medicine, University of Ulsan Ulsan (Korea, Republic of); Ha, Sung Whan [Seoul National University College of Medicine, Seoul (Korea, Republic of)

    2004-03-15

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

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

    International Nuclear Information System (INIS)

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

  13. CT Guided Bone Biopsy Using a Battery Powered Intraosseous Device

    Energy Technology Data Exchange (ETDEWEB)

    Schnapauff, Dirk, E-mail: dirk.schnapauff@charite.de; Marnitz, Tim, E-mail: tim.marnitz@charite.de; Freyhardt, Patrick, E-mail: Patrick.freyhardt@charite.de; Collettini, Federico, E-mail: Federico.collettini@charite.de [Charite Universitaetsmedizin Berlin, Campus Virchow-Klinikum, Department of Radiology (Germany); Hartwig, Kerstin, E-mail: kerstin.hartwig@charite.de [Charite Universitaetsmedizin Berlin, Campus Charite Mitte, Department of Haematology and Oncology (Germany); Joehrens, Korinna, E-mail: korinna.joehrens@charite.de [Charite Universitaetsmedizin Berlin, Campus Charite Mitte, Department of Pathology (Germany); Hamm, Bernd, E-mail: bernd.hamm@charite.de; Kroencke, Thomas, E-mail: thomas.kroencke@charite.de; Gebauer, Bernhard, E-mail: Bernhard.gebauer@charite.de [Charite Universitaetsmedizin Berlin, Campus Virchow-Klinikum, Department of Radiology (Germany)

    2013-10-15

    Purpose: To evaluate the feasibility of a battery powered intraosseous device to perform CT-fluoroscopy guided bone biopsy. Methods: Retrospective analysis of 12 patients in whom bone specimen were acquired from different locations under CT-fluoroscopy guidance using the OnControl bone marrow biopsy system (OBM, Vidacare, Shavano Park, TX, USA). Data of the 12 were compared to a historic cohort in whom the specimen were acquired using the classic Jamshidi Needle, as reference needle using manual force for biopsy. Results: Technical success was reached in 11 of 12 cases, indicated by central localisation of the needle within the target lesion. All specimen sampled were sufficient for histopathological workup. Compared to the historical cohort the time needed for biopsy decreased significantly from 13 {+-} 6 to 6 {+-} 4 min (P = 0.0001). Due to the shortened intervention time the radiation dose (CTDI) during CT-fluoroscopy was lowered significantly from 169 {+-} 87 to 111 {+-} 54 mGy Multiplication-Sign cm (P = 0.0001). Interventional radiologists were confident with the performance of the needle especially when using in sclerotic or osteoblastic lesions. Conclusion: The OBM is an attractive support for CT-fluoroscopy guided bone biopsy which is safe tool and compared to the classical approach using the Jamshidi needle leading to significantly reduced intervention time and radiation exposure.

  14. A simulation study on proton computed tomography (CT) stopping power accuracy using dual energy CT scans as benchmark

    DEFF Research Database (Denmark)

    Hansen, David Christoffer; Seco, Joao; Sørensen, Thomas Sangild;

    2015-01-01

    development) have both been proposed as methods for obtaining patient stopping power maps. The purpose of this work was to assess the accuracy of proton CT using dual energy CT scans of phantoms to establish reference accuracy levels. Material and methods. A CT calibration phantom and an abdomen cross section...... of detectors and the corresponding noise characteristics. Stopping power maps were calculated for all three scans, and compared with the ground truth stopping power from the phantoms. Results. Proton CT gave slightly better stopping power estimates than the dual energy CT method, with root mean square errors...

  15. Acquiring 4D Thoracic CT Scans Using Ciné CT Acquisition

    Science.gov (United States)

    Low, Daniel

    One method for acquiring 4D thoracic CT scans is to use ciné acquisition. Ciné acquisition is conducted by rotating the gantry and acquiring x-ray projections while keeping the couch stationary. After a complete rotation, a single set of CT slices, the number corresponding to the number of CT detector rows, is produced. The rotation period is typically sub second so each image set corresponds to a single point in time. The ciné image acquisition is repeated for at least one breathing cycle to acquire images throughout the breathing cycle. Once the images are acquired at a single couch position, the couch is moved to the abutting position and the acquisition is repeated. Post-processing of the images sets typically resorts the sets into breathing phases, stacking images from a specific phase to produce a thoracic CT scan at that phase. Benefits of the ciné acquisition protocol include, the ability to precisely identify the phase with respect to the acquired image, the ability to resort images after reconstruction, and the ability to acquire images over arbitrarily long times and for arbitrarily many images (within dose constraints).

  16. Radiological Appearance of Extrapulmonary Lesions in Rradiography (CT scan-MRI

    Directory of Open Access Journals (Sweden)

    A. Soltani Shirazi

    2005-08-01

    Full Text Available Introduction & Background: To make the diagnosis of chest lesions in chest radiography or CT scan easier, lesions are divided into three main groups: lesions of lung parenchyma, lesions of the heart and mediasti-num and lesions with origins of the protective tissues in the chest. Extrapulmonary lesions have various origins ranging from hard tissues like the bone, to soft tissues such as bone marrow or fatty tissue; they usu-ally present with diverse and sometimes misleading signs and symptoms. Knowledge about the radiologic semiolology of these instances helps to prevent mis-taking these lesions with lesions of pulmonary origin. Consequently timely and appropriate treatment can be provided. Here a study of five thousand chest radi-ographies of extrapulmonary lesions with primary diagnosis of pulmonary lesions is presented and the approach to diagnosis is discussed. According to the present study, 56% of extrapulmonary lesions are de-tectable by means of simple primary radiography and by considering radiologic semiology. We reached definite diagnosis by means of lung CT scan. Other lesions were diagnosed after performing biopsy or surgery.

  17. Radionuclides and the normal bone scan

    International Nuclear Information System (INIS)

    Recently, Eisenhut and co-workers have described development of iodine-131 labeled diphosphonates for palliative treatment of bone metastases. The compound labeled was alpha-amino (4-hydroxybenzylidene) diphosphonate (BDP3). Other beta-emitting radionuclides have been used for treatment of intractable pain secondary to bone metastases. These include strontium-89, which has some difficulties, particularly in terms of disposal of the excretions due to the long physical half-life of the life of the radionuclide. Yttrium-90 has also been used but has a relatively high hepatic uptake. Phosphorus-32 labeled compounds have also been used. Although palliation has been described, bone marrow depression has also occurred. Rhenium-186 also has been suggested, however, high renal uptake is a problem. At present, the iodine-131 labeled BDP3 appears to be the best of the available therapeutic radiopharmaceuticals. One of the major disadvantages in use of this compound is the production of gamma photons. While undesirable from a dosimetry viewpoint, gamma photons do, however, permit imaging if desired

  18. Light scattering in optical CT scanning of Presage dosimeters

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Y; Adamovics, J; Cheeseborough, J C; Chao, K S; Wuu, C S, E-mail: yx2010@columbia.ed

    2010-11-01

    The intensity of the scattered light from the Presage dosimeters was measured using a Thorlabs PM100D optical power meter (Thorlabs Inc, Newton, NJ) with an optical sensor of 1 mm diameter sensitive area. Five Presage dosimeters were made as cylinders of 15.2 cm, 10 cm, 4 cm diameters and irradiated with 6 MV photons using a Varian Clinac 2100EX. Each dosimeter was put into the scanning tank of an OCTOPUS' optical CT scanner (MGS Research Inc, Madison, CT) filled with a refractive index matching liquid. A laser diode was positioned at one side of the water tank to generate a stationary laser beam of 0.8 mm width. On the other side of the tank, an in-house manufactured positioning system was used to move the optical sensor in the direction perpendicular to the outgoing laser beam from the dosimeters at an increment of 1 mm. The amount of scattered photons was found to be more than 1% of the primary light signal within 2 mm from the laser beam but decreases sharply with increasing off-axis distance. The intensity of the scattered light increases with increasing light attenuations and/or absorptions in the dosimeters. The scattered light at the same off-axis distance was weaker for dosimeters of larger diameters and for larger detector-to-dosimeter distances. Methods for minimizing the effect of the light scattering in different types of optical CT scanners are discussed.

  19. Investigation of normal intrathoracic trachea during dynamic CT scanning

    International Nuclear Information System (INIS)

    Purpose: To study the diameters and cross-sectional areas, as well as the shape of normal adult intrathoracic trachea during forced respiration in the Chinese. Materials and methods: 25 male volunteers were studied with dynamic CT, using electron beam CT scanner, at a level 2 cm above aortic arch, with 3 mm collimation. Ten 100-msec dynamic scans were obtained at 500-msec intervals during 5.5-second period as the volunteers performed forced inspiration and expiration vital capacity maneuvers. Results: The mean cross-sectional area, sagittal and coronal diameter of the trachea decreased dynamically from 228.36 mm2, 18.28 mm and 16.97 mm at end inspiration to 191.24 mm2, 15.62 mm and 16.19 mm at end expiration respectively. The average cross-section area decreased by 15.48% +- 9.6% between inspiration and expiration. The shape of trachea was rounded or elliptical on inspiration image and horseshoe shaped on end of expiration. Conclusion: The dynamic CT is ideally suited for the study of tracheal dimensions and shape during respiration maneuvers. Among the Chinese, if the cross-sectional area of trachea decrease by more than 50% from inspiration to expiration, diagnosis of tracheomalacia can be established

  20. Scan Quality and Entrance Skin Dose in Thoracic CT: A Comparison between Bismuth Breast Shield and Posteriorly Centered Partial CT Scans

    OpenAIRE

    Tappouni, Rafel; Mathers, Bradley

    2013-01-01

    Objectives. To compare the effectiveness of the bismuth breast shield and partial CT scan in reducing entrance skin dose and to evaluate the effect of the breast shield on image quality (IQ). Methods. Nanodots were placed on an adult anthropomorphic phantom. Standard chest CT, CT with shield, and partial CT were performed. Nanodot readings and effective doses were recorded. 50 patients with chest CTs obtained both with and without breast shields were reviewed. IQ was evaluated by two radiolog...

  1. CT Scans of Soil Specimen Processed in Space

    Science.gov (United States)

    1998-01-01

    CT scans of the spcimens on STS-79 reveal internal cone-shaped features and radial patterns not seen in specimens processed on the ground. The lighter areas are the densest in these images. CT scans produced richly detailed images allowing scientists to build 3D models of the interior of the specimens that can be compared with microscopic examination of thin slices. This view depict horizontal slices from top to bottom of a flight specimen. Sand and soil grains have faces that can cause friction as they roll and slide against each other, or even cause sticking and form small voids between grains. This complex behavior can cause soil to behave like a liquid under certain conditions such as earthquakes or when powders are handled in industrial processes. Mechanics of Granular Materials (MGM) experiments aboard the Space Shuttle use the microgravity of space to simulate this behavior under conditions that carnot be achieved in laboratory tests on Earth. MGM is shedding light on the behavior of fine-grain materials under low effective stresses. Applications include earthquake engineering, granular flow technologies (such as powder feed systems for pharmaceuticals and fertilizers), and terrestrial and planetary geology. Nine MGM specimens have flown on two Space Shuttle flights. Another three are scheduled to fly on STS-107. The principal investigator is Stein Sture of the University of Colorado at Boulder. Credit: Los Alamos National Laboratory and the University of Colorado at Boulder.

  2. Multi-detector row CT scanning in Paleoanthropology at various tube current settings and scanning mode.

    Science.gov (United States)

    Badawi-Fayad, J; Yazbeck, C; Balzeau, A; Nguyen, T H; Istoc, A; Grimaud-Hervé, D; Cabanis, E- A

    2005-12-01

    The purpose of this study was to determine the optimal tube current setting and scanning mode for hominid fossil skull scanning, using multi-detector row computed tomography (CT). Four fossil skulls (La Ferrassie 1, Abri Pataud 1, CroMagnon 2 and Cro-Magnon 3) were examined by using the CT scanner LightSpeed 16 (General Electric Medical Systems) with varying dose per section (160, 250, and 300 mAs) and scanning mode (helical and conventional). Image quality of two-dimensional (2D) multiplanar reconstructions, three-dimensional (3D) reconstructions and native images was assessed by four reviewers using a four-point grading scale. An ANOVA (analysis of variance) model was used to compare the mean score for each sequence and the overall mean score according to the levels of the scanning parameters. Compared with helical CT (mean score=12.03), the conventional technique showed sustained poor image quality (mean score=4.17). With the helical mode, we observed a better image quality at 300 mAs than at 160 in the 3D sequences (P=0.03). Whereas in native images, a reduction in the effective tube current induced no degradation in image quality (P=0.05). Our study suggests a standardized protocol for fossil scanning with a 16 x 0.625 detector configuration, a 10 mm beam collimation, a 0.562:1 acquisition mode, a 0.625/0.4 mm slice thickness/reconstruction interval, a pitch of 5.62, 120 kV and 300 mAs especially when a 3D study is required. PMID:16211320

  3. Clinical analysis of bone scanning in solitary lesion

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    A rational analysis procedure for solitary lesions on whole bone scan-ning was offered. This study was undertaken to analyze retrospectively solitary le-sions which obtained final diagnose through the following aspects: (1) diagnosis ofbone metastasis, (2) the incidence of bone metastasis in different tumor, (3) the mostpossible lesion sites indicating bone metastasis, (4) morphological analysis of solitarylesions. The results are: (1) The incidence of solitary lesions in 2465 cases on wholebone scanning is 15.3%. (2) The rate of bone metastasis is 24.8% in 282 patientswith primary malignancy. The rate of bone metastasis is 6.3% in 64 patients withoutprimary malignancy, and the total diagnostic rate of bone metastasis is 21.4% in 346patients. (3) In patients with primary malignancy, the incidence of bone metastasis ofsolitary lesions is as follows respectively: bronchi cancer 36.1%(22/61); breast cancer23.8%(20/84); prostate gland 17.2%(5/29); other urinary system cancer 22.2%(4/18):G.I. system cancer 16.9%(10/59); others 29.0%(9/31). There is no significant differ-ence in different cancer. (4) In patients without primary malignancy, 93.7%(60/64) ofsolitary lesions are benign. (5) From anatomical point of view, we found the diagnos-tic rate of bone metastasis is as follow: 30% in spine; 34.2% in pelvis; 36.4% in skull;10.8% in other bones. There are significant differences in four groups. It is concludedthat: (1) The diagnostic rate of bone metastasis in solitary lesions is 21.4%. (2) Themost possible solitary lesions indicating osseous tumor spread are at spine, pelvic andskull. (3) Special attention to "cold" and streak like lesions should be paid. (4) Aclinical analysis procedure for diagnosis of solitary lesions has been summarized outhere.``

  4. The herniation pit, a common cause of focal uptake in the femoral neck bone scan. Positive and differential diagnosis in osseous SPECT/CT; L'herniation pit, une cause frequente d'hyperfixation focale du col femoral en scintigraphie osseuse. Diagnostic positif et differentiel en TEMP/TDM osseuse

    Energy Technology Data Exchange (ETDEWEB)

    Girma, A. [Centre Antoine-Lacassagne, Service de medecine nucleaire, 06 - Nice (France); Ramadan, A.; Paycha, F. [Hopital Louis-Mourier, service de medecine nucleaire, 92 - Colombes (France); Baccarc, S. [Hopital Louis-Mourier, service de radiologie, 92 - Colombes (France)

    2010-07-01

    The distinction of the various possible diagnoses in front of a focal uptake in the femoral neck in bone SPECT / CT is based on a triad of criteria that are symptomatic or not of the injury, its precise scintigraphy location at the femoral neck and CT appearance. (N.C.)

  5. Case of pycnodysostosis. Observation of skull by CT scan

    Energy Technology Data Exchange (ETDEWEB)

    Anegawa, Shigetaka; Bekki, Yoshiaki; Furukawa, Yasuhiro; Yokota, Seishi; Torigoe, Ryuichiro

    1987-07-01

    A 13-year-old boy was presented to the Department of Neurosurgery, Saiseikai Fukuoka General Hospital for further examinations concerning abnormal findings in the skull radiogram taken when he struck his head. His physical features showed some characteristics the same as those of pycnodysostosis as follows - proportionate dwarfism, prominent forehead, short spoon-shaped fingers, bilateral exophthalmos. A skull radiogram revealed widely open cranial sutures with no healing of the fracture and craniotomy which was performed for an acute epidural hematoma 6 years ago. Furthermore, the mandible was hypoplastic with a virtural loss of mandibular angle. CT of the soft tissues showed somewhat dilated cortical sulci and ventricles without any structural abnormalities in the brain. CT of bone algorythum revealed specific characteristics of this disease. The paranasal sinuses were quite hypoplastic. Especially in the maxillary sinuses, frontal sinussus and mastoid air cells, none of developments of sinuses were noted, even though the middle and internal ear seemed to be normal. Moreover, the ethomoid and sphenoid sinuses were noted, although their developments were poor. The appearance of skull base was normal, including the inlets and outlets of cranial nerves or vessels and synchondroses. However, the density of the skull base, especially in the diploe, was higher than normal in Hansfield number. Furthermore, detailed measurements of skull base demonstrated that the skull base itself was also dwarfish. In our study, the development of sinuses in bones with intramembranous ossification are worse than that with endochondral ossification. Furthermore, sutures or synchondroses in the skull base were well-developed than those of the convex. So, it is considered that pycnodysostosis must be the neighboring entity of diseases such as achondroplastic dwarfism or cleidocranial dysplasia. (J.P.N.).

  6. Influence of object location in different FOVs on trabecular bone microstructure measurements of human mandible: a cone beam CT study

    NARCIS (Netherlands)

    N. Ibrahim; A. Parsa; B. Hassan; P. van der Stelt; I.H.A. Aartman; P. Nambiar

    2014-01-01

    The aim of this study was to assess the influence of different object locations in different fields of view (FOVs) of two cone beam CT (CBCT) systems on trabecular bone microstructure measurements of a human mandible. A block of dry human mandible was scanned at five different locations (centre, lef

  7. A study evaluating the dependence of the patient dose on the CT dose change in a SPECT/CT scan

    Science.gov (United States)

    Kim, Woo-Hyun; Kim, Ho-Sung; Dong, Kyung-Rae; Chung, Woon-Kwan; Cho, Jae-Hwan; Shin, Jae-Woo

    2012-07-01

    This study assessed ways of reducing the patient dose by examining the dependence of the patient dose on the CT (computed tomography) dose in a SPECT (single-photon emission computed tomography)/CT scan. To measure the patient dose, we used Precedence 16 SPECT/CT along with a phantom for the CT dose measurement (CT dose phantom kit for adult's head and body, Model 76-414-4150), a 100-mm ionization chamber (CT Ion Chamber) and an X-ray detector (Victoreen Model 4000M+). In addition, the patient dose was evaluated under conditions similar to those for an actual examination using an ImPACT (imaging performance assessment of CT scanners) dosimetry calculator in the Monte Carlo simulation method. The experimental method involved the use of a CT dose phantom to measure the patient dose under different CT conditions (kVp and mAs) to determine the CTDI (CT dose index) under each condition. An ImPACT dosimetry calculator was also used to measure CTDIw (CT dose index water ), CTDIv (CT dose index volume ), DLP (dose-length product), and effective dose. According to the patient dose measurements using the CT dose phantom, the CTDI showed an approximately 54 fold difference between when the maximum (140 kVp and 250 mAs) and the minimum dose (90 kVp and 25 mAs) was used. The CTDI showed a 4.2 fold difference between the conditions (120 kVp and 200 mAs) used mainly in a common CT scan and the conditions (120 kVp and 50 mAs) used mainly in a SPECT/CT scan. According to the measurement results using the dosimetry calculator, the effective dose showed an approximately 35 fold difference between the conditions for the maximum and the minimum doses, as in the case with the CT dose phantom. The effective dose showed a 4.1 fold difference between the conditions used mainly in a common CT scan and those used mainly in a SPECT/CT scan. This study examined the patient dose by reducing the CT dose in a SPECT/CT scan. As various examinations can be conducted due to the development of

  8. Survey on scanning pediatric patients' heads with CT

    International Nuclear Information System (INIS)

    Pediatric patients are especially sensitive to radiation, and when scanning their heads with CT, it is necessary to do so with a low dose and pay very close attention. However, there are many problems when scanning pediatric patients, and it is often confusing to set the conditions for scanning. To do a survey and comparison, we issued a questionnaire to 23 pediatric hospitals and 89 university hospitals, asking about their usage of sedation, studied disorders, as well as how and under what conditions they scan their patients. The percentage of response was 40% in total. Based on the questionnaire results, we could not see much difference in the conditions for scanning. However, there was a significant difference in the usage of sedation and studied disorders between pediatric hospitals and university hospitals. The most studied disorders at pediatric hospitals were convulsion and consciousness disorders, and low-contrast areas such as the albocinereous, which requires images without movement artifacts. In order to obtain clear images, the patient was put under sedation. On the other hand, university hospitals often deal with external injuries, which usually involve danger in using sedation, and patients are usually examined without it. In addition, the usage of sedation is rare because bleeding brings up high-contrast images, and it is easy to make a diagnosis even if there is some movement artifact. Also to aim at setting a standard for medical technology, from here on, guidelines of examining methods and setting conditions should be made depending on how the different disorders should be treated. (author)

  9. Effect of low-dose CT and iterative reconstruction on trabecular bone microstructure assessment

    Science.gov (United States)

    Kopp, Felix K.; Baum, Thomas; Nasirudin, Radin A.; Mei, Kai; Garcia, Eduardo G.; Burgkart, Rainer; Rummeny, Ernst J.; Bauer, Jan S.; Noël, Peter B.

    2016-03-01

    The trabecular bone microstructure is an important factor in the development of osteoporosis. It is well known that its deterioration is one effect when osteoporosis occurs. Previous research showed that the analysis of trabecular bone microstructure enables more precise diagnoses of osteoporosis compared to a sole measurement of the mineral density. Microstructure parameters are assessed on volumetric images of the bone acquired either with high-resolution magnetic resonance imaging, high-resolution peripheral quantitative computed tomography or high-resolution computed tomography (CT), with only CT being applicable to the spine, which is one of clinically most relevant fracture sites. However, due to the high radiation exposure for imaging the whole spine these measurements are not applicable in current clinical routine. In this work, twelve vertebrae from three different donors were scanned with standard and low radiation dose. Trabecular bone microstructure parameters were assessed for CT images reconstructed with statistical iterative reconstruction (SIR) and analytical filtered backprojection (FBP). The resulting structure parameters were correlated to the biomechanically determined fracture load of each vertebra. Microstructure parameters assessed for low-dose data reconstructed with SIR significantly correlated with fracture loads as well as parameters assessed for standard-dose data reconstructed with FBP. Ideal results were achieved with low to zero regularization strength yielding microstructure parameters not significantly different from those assessed for standard-dose FPB data. Moreover, in comparison to other approaches, superior noise-resolution trade-offs can be found with the proposed methods.

  10. Thoracic red bone marrow dose evaluation in CT of patients with carcinoma of the testes

    Energy Technology Data Exchange (ETDEWEB)

    Cruickshank, L. (Mayday Univ. Hospital, London (United Kingdom))

    1994-02-01

    At the Royal Marsden Hospital many patients are treated for testicular tumours. These patients initially undergo orchidectomy to remove the affected testicle and staging of the disease is also assessed at surgery. Patients classified as stage one, which is testicular involvement alone with no evidence of metastases, are placed on a surveillance, or watch, policy. This involves monthly or bi-monthly chest x-rays, depending on the disease, tumour marker tests and regular CT scans of the chest, abdomen and pelvis, during the first year. As these patients are young, the age range being 15-35 years and the five year survival rate for all testicular tumours is 97%, the radiation dose they were receiving from the CT scans alone warranted investigation, because a high percentage of the body's red bone marrow (33%) is contained within the thorax, and these patients always have a CT scan of the thorax to identify the presence of any intra-thoracic metastases. The aim of this project was to assess the radiation dose to the red bone marrow of the thorax to discover if this dose approached a level at which radiation induced detriment might be significant. (author).

  11. To Scan or not to Scan: Consideration of Medical Benefit in the Justification of CT Scanning.

    Science.gov (United States)

    McCollough, Cynthia H

    2016-03-01

    While there are ongoing debates with regard to the level of risk, if any, associated with medical imaging, the benefits from medical imaging exams are well documented. This forum article looks at outcome-based medical studies and guidance from expert panels in an effort to bring the benefits of medical imaging, specifically CT imaging, into focus. The position is taken that imaging, medical, and safety communities must not continue to discuss small hypothetical risks from ionizing radiation without emphasizing the large well-documented benefits from medical imaging exams that use ionizing radiation. PMID:26808885

  12. Effect of spineboard and headblocks on the image quality of head CT scans.

    Science.gov (United States)

    Hemmes, Baukje; Jeukens, Cécile R L P N; Al-Haidari, Aliaa; Hofman, Paul A M; Vd Linden, Ed S; Brink, Peter R G; Poeze, Martijn

    2016-06-01

    Trauma patients at risk for, or suspected of, spinal injury are frequently transported to hospital using full spinal immobilisation. At the emergency department, immobilisation is often maintained until radiological work-up is completed. In this study, we examined how these devices for spinal stabilization influence visual image quality. Image quality was judged for both patient CT scans and phantom CT scans. CT scans of 217 patients were assessed retrospectively by two radiologists for visual scoring of image quality, scoring both quantity and impact of artifacts caused by the immobilization devices. For the phantom CT scans, eight set-ups were made, using a vacuum mattress without headblocks and a rigid and a soft-layered spineboard without headblocks, with standard soft-foam headblocks, or with new design headblocks. Overall, artifacts were found in 67 % of CT scans of patients on immobilization devices, which hampered diagnosis in 10 % of the cases. In the phantom CT scans, artifacts were present in all set-ups with one or more devices present and were seen in 20 % of all scan slices. The presence of headblocks resulted in more artifacts in both the patient CT scans and the phantom CT scans. Considerable effort should therefore be made to adjust the design of the immobilization devices and to remove the headblocks before CT scans are made. PMID:27091739

  13. Confocal laser scanning microscopy in study of bone calcification

    Energy Technology Data Exchange (ETDEWEB)

    Nishikawa, Tetsunari, E-mail: tetsu-n@cc.osaka-dent.ac.jp [Department of Oral Pathology, Osaka Dental University, Osaka (Japan); Kokubu, Mayu; Kato, Hirohito [Department of Oral Pathology, Osaka Dental University, Osaka (Japan); Imai, Koichi [Department of Biomaterials, Osaka Dental University, Osaka (Japan); Tanaka, Akio [Department of Oral Pathology, Osaka Dental University, Osaka (Japan)

    2012-12-01

    Highlights: Black-Right-Pointing-Pointer High-magnification images with depth selection, and thin sections were observed using CLSM. Black-Right-Pointing-Pointer The direction and velocity of calcification of the bone was observed by administration of 2 fluorescent dyes. Black-Right-Pointing-Pointer In dog femora grafted with coral blocks, newly-formed bone was observed in the coral block space with a rough surface. Black-Right-Pointing-Pointer Twelve weeks after dental implant was grafted in dog femora, the space between screws was filled with newly-formed bones. - Abstract: Bone regeneration in mandible and maxillae after extraction of teeth or tumor resection and the use of rough surface implants in bone induction must be investigated to elucidate the mechanism of calcification. The calcified tissues are subjected to chemical decalcification or physical grinding to observe their microscopic features with light microscopy and transmission electron microscopy where the microscopic tissue morphology is significantly altered. We investigated the usefulness of confocal laser scanning microscopy (CLSM) for this purpose. After staggering the time of administration of calcein and alizarin red to experimental rats and dogs, rat alveolar bone and dog femur grafted with coral as scaffold or dental implants were observed with CLSM. In rat alveolar bone, the calcification of newly-formed bone and net-like canaliculi was observed at the mesial bone from the roots progressed at the rate of 15 {mu}m/day. In dog femur grafted with coral, newly-formed bones along the space of coral were observed in an orderly manner. In dog femur with dental implants, after 8 weeks, newly-formed bone proceeded along the rough surface of the implants. CLSM produced high-magnification images of newly-formed bone and thin sections were not needed.

  14. Whole-body [{sup 18}F]FDG PET/MRI vs. PET/CT in the assessment of bone lesions in oncological patients: initial results

    Energy Technology Data Exchange (ETDEWEB)

    Beiderwellen, Karsten; Huebner, Michael; Grueneisen, Johannes; Nensa, Felix; Kuehl, Hilmar; Umutlu, Lale; Lauenstein, Thomas C. [University of Duisburg-Essen, Department of Diagnostic and Interventional Radiology and Neuroradiology, University Hospital Essen, Essen (Germany); Heusch, Philipp [University of Duesseldorf, Department of Diagnostic and Interventional Radiology, Medical Faculty, Duesseldorf (Germany); Ruhlmann, Verena; Rosenbaum-Krumme, Sandra [University of Duisburg-Essen, Department of Nuclear Medicine, University Hospital Essen, Essen (Germany)

    2014-08-15

    To compare [{sup 18} F]FDG PET/MRI with PET/CT for the assessment of bone lesions in oncologic patients. This prospective study included 67 patients with solid tumours scheduled for PET/CT with [{sup 18} F]FDG who also underwent a whole-body PET/MRI scan. The datasets (PET/CT, PET/MRI) were rated by two readers regarding lesion conspicuity (four-point scale) and diagnostic confidence (five-point scale). Median scores were compared using the Wilcoxon test. Bone metastases were present in ten patients (15 %), and benign bone lesions in 15 patients (22 %). Bone metastases were predominantly localized in the pelvis (18 lesions, 38 %) and the spine (14 lesions, 29 %). Benign bone lesions were exclusively osteosclerotic and smaller than the metastases (mean size 6 mm vs. 23 mm). While PET/CT allowed identification of 45 of 48 bone metastases (94 %), PET/MRI allowed identification of all bone metastases (100 %). Conspicuity of metastases was high for both modalities with significantly better results using PET/MRI (p < 0.05). Diagnostic confidence in lesion detection was high for both modalities without a significant difference. In benign lesions, conspicuity and diagnostic confidence were significantly higher with PET/CT (p < 0.05). [{sup 18} F]FDG PET/MRI shows high potential for the assessment of bone metastases by offering superior lesion conspicuity when compared to PET/CT. In hypersclerotic, benign bone lesions PET/CT still sets the reference. (orig.)

  15. Exploring miniature insect brains using micro-CT scanning techniques.

    Science.gov (United States)

    Smith, Dylan B; Bernhardt, Galina; Raine, Nigel E; Abel, Richard L; Sykes, Dan; Ahmed, Farah; Pedroso, Inti; Gill, Richard J

    2016-01-01

    The capacity to explore soft tissue structures in detail is important in understanding animal physiology and how this determines features such as movement, behaviour and the impact of trauma on regular function. Here we use advances in micro-computed tomography (micro-CT) technology to explore the brain of an important insect pollinator and model organism, the bumblebee (Bombus terrestris). Here we present a method for accurate imaging and exploration of insect brains that keeps brain tissue free from trauma and in its natural stereo-geometry, and showcase our 3D reconstructions and analyses of 19 individual brains at high resolution. Development of this protocol allows relatively rapid and cost effective brain reconstructions, making it an accessible methodology to the wider scientific community. The protocol describes the necessary steps for sample preparation, tissue staining, micro-CT scanning and 3D reconstruction, followed by a method for image analysis using the freeware SPIERS. These image analysis methods describe how to virtually extract key composite structures from the insect brain, and we demonstrate the application and precision of this method by calculating structural volumes and investigating the allometric relationships between bumblebee brain structures. PMID:26908205

  16. Centre for Industrial Application of CT scanning (CIA-CT) – Four years of results 2009-2013

    DEFF Research Database (Denmark)

    De Chiffre, Leonardo; Andreasen, Jan Lasson; Christensen, Lars Bager;

    as a centre of excellence for industrial CT scanning, both nationally and internationally. A network with approx. 40 participants has been established, and a total of 22 students have been educated. Dissemination activities have encompassed: a web page www.cia-ct.mek.dtu.dk , 8 newsletters, 4 topical...... conferences, 5 seminars and workshops, and 61 publications. Collaboration has been established with a number of national and international actors in the field of CT, including societies and research organisations. Five major research projects have been carried out: 1) CT scanning for coordinate metrology; 2...

  17. Improving Depiction of Temporal Bone Anatomy With Low-Radiation Dose CT by an Integrated Circuit Detector in Pediatric Patients

    Science.gov (United States)

    He, Jingzhen; Zu, Yuliang; Wang, Qing; Ma, Xiangxing

    2014-01-01

    Abstract The purpose of this study was to determine the performance of low-dose computed tomography (CT) scanning with integrated circuit (IC) detector in defining fine structures of temporal bone in children by comparing with the conventional detector. The study was performed with the approval of our institutional review board and the patients’ anonymity was maintained. A total of 86 children  0.05). The low-dose CT images acquired with the IC detector provide better depiction of fine osseous structures of temporal bone than that with the conventional DC detector. PMID:25526489

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

    International Nuclear Information System (INIS)

    Micro Computed Tomography (μCT) has been largely used to perform micrometer scale imaging of specimens, bone biopsies and small animals for the study of porous or cavity-containing objects. One of its favored applications is for assessing structural properties of bone. In this research, we perform a pilot study to visualize and characterize bone structure of a chicken bone thigh, as well as to delineate its cortical and trabecular bone regions. We utilize an In-Vitro μCT scanner Skyscan 1173 to acquire a three dimensional image data of a chicken bone thigh. The thigh was scanned using X-ray voltage of 45 kV and current of 150 μA. The reconstructed images have spatial resolution of 142.50 μm/pixel. Using image processing and analysis e.i segmentation by thresholding the gray values (which represent the pseudo density) and binarizing the images, we were able to visualize each part of the bone, i.e., the cortical and trabecular regions. Total volume of the bone is 4663.63 mm3, and the surface area of the bone is 7913.42 mm2. The volume of the cortical is approximately 1988.62 mm3 which is nearly 42.64% of the total bone volume. This pilot study has confirmed that the μCT is capable of quantifying 3D bone structural properties and defining its regions separately. For further development, these results can be improved for understanding the pathophysiology of bone abnormality, testing the efficacy of pharmaceutical intervention, or estimating bone biomechanical properties

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2014-03-24

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

  20. Comparison of Preoperative Temporal Bone CT with Intraoperative Findings in Patients with Cholesteatoma

    Directory of Open Access Journals (Sweden)

    Mehrdad Rogha

    2014-01-01

    Full Text Available Introduction: Cholesteatoma is traditionally diagnosed by otoscopic examination and treated by surgery. The necessity for imaging in an uncomplicated case is controversial. This study was planned to investigate the usefulness of a preoperative high-resolution computed tomography (HRCT scan in depicting the status of middle ear structures in the presence of cholesteatoma and also to compare the correspondence between pre- and intraoperative CT findings in patients with cholesteatoma.   Materials and Methods: This prospective descriptive study was performed from January 2009 to May 2011 in 36 patients with cholesteatoma who were referred to the Kashani and Al-Zahra Clinics of Otolaryngology. Preoperative high-resolution temporal bone CT scans (axial and coronal views were carried out and compared with intraoperative findings.   Results: Evaluation of 36 patients and their CT scans revealed excellent correlation for sigmoid plate erosion, widening of aditus, and erosion of scutum; good correlation for erosion of malleus and tegmen; moderate correlation for lateral canal fistula (LCF and erosion of mastoid air cells; and poor correlation for facial nerve dehiscence (FND, incus, and stapes erosion.    Conclusion:  A preoperative CT scan may be helpful in relation to diagnosis and decision making for surgery in cases of cholesteatoma and ossicular erosion. The CT scan can accurately predict the extent of disease and is helpful for detection of lateral canal fistula, erosions of dural plate, and ossicular erosions. However it is not able to distinguish between cholesteatoma and mucosal disease, facial nerve dehiscency, incus, and stapes erosion. 

  1. Indeterminate lesions on planar bone scintigraphy in lung cancer patients: SPECT, CT or SPECT-CT?

    Energy Technology Data Exchange (ETDEWEB)

    Sharma, Punit; Kumar, Rakesh; Singh, Harmandeep; Bal, Chandrasekhar; Malhotra, Arun [All India Institute of Medical Sciences, Department of Nuclear Medicine, New Delhi (India); Julka, Pramod Kumar [All India Institute of Medical Sciences, Department of Radiation Oncology, New Delhi (India); Thulkar, Sanjay [All India Institute of Medical Sciences, Department of Radiodiagnosis, New Delhi (India)

    2012-07-15

    The objective of the present study was to compare the role of single photon emission computed tomography (SPECT), computed tomography (CT) and SPECT-CT of selected volume in lung cancer patients with indeterminate lesions on planar bone scintigraphy (BS). The data of 50 lung cancer patients (53 {+-} 10.3 years; range 30-75; male/female 38/12) with 65 indeterminate lesions on planar BS (January 2010 to November 2010) were retrospectively evaluated. All of them underwent SPECT-CT of a selected volume. SPECT, CT and SPECT-CT images were independently evaluated by two experienced readers (experience in musculoskeletal imaging, including CT: 5 and 7 years) in separate sessions. A scoring scale of 1 to 5 was used, in which 1 is definitely metastatic, 2 is probably metastatic, 3 is indeterminate, 4 is probably benign and 5 is definitely benign. Sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) were calculated for each modality, taking a score {<=}2 as metastatic. With receiver operating characteristic (ROC) curve analysis, areas under the curve (AUC) were calculated for each modality and compared. Clinical and imaging follow-up and/or histopathology were taken as reference standard. For both readers SPECT was inferior to CT (P = 0.004, P = 0.022) and SPECT-CT (P = 0.003, P = 0.037). However, no significant difference was found between CT and SPECT-CT for reader 1 (P = 0.847) and reader 2 (P = 0.592). The findings were similar for lytic as well as sclerotic lesions. Moderate inter-observer agreement was seen for SPECT images ({kappa} = 0.426), while almost perfect agreement was seen for CT ({kappa} = 0.834) and SPECT-CT ({kappa} = 0.971). CT alone and SPECT-CT are better than SPECT for accurate characterisation of indeterminate lesions on planar BS in lung cancer patients. CT alone is not inferior to SPECT-CT for this purpose and might be preferred because of shorter acquisition time and wider availability. (orig.)

  2. CT evaluation of solitary pulmonary nodule : value of additional HRCT scan

    International Nuclear Information System (INIS)

    The aim of our study was to evaluate the usefulness of high-resolution CT scans in addition to helical CT for characterizing a solitary pulmonary nodule. Our study included 49 patients with a solitary pulmonary nodule ; in each patient this was evaluated by both additional high-resolution CT and helical scanning. Images were evaluated by three independent observers, each of whom read them twice : initially with helical CT images only and then with helical images plus high-resolution CT images. After analysis, the observers recorded the following : histologic diagnosis, benignancy or malignancy of a nodule, and confidence in their diagnosis (three scales). In differentiating benign and malignant nodules, the accuracy of helical scans only was 75% (110/147 readings) whereas that of helical plus high-resolution CT scans was 82% (121/147 readings)(ρ=0.001). Correct histologic diagnosis was made in 47% of cases (69/147 readings) when helical scans only had been evaluated and in 48% of cases (71/147 readings) for which both helical and high-resolotion CT scans were available (ρ=0.815). Diagnosis was more often highly confident on the basis of additional high-resolution CT scans (25%) than helical scans only (5%) (ρ=0.001). By enhancing differential diagnostic accuracy between benign and malignant nodules and by increasing confidence in the histologic diagnosis of a pulmonary nodule, additional high-resolution CT scans are valuable for the evaluation of a solitary pulmonary nodule

  3. Computed Tomography (CT) -- Sinuses

    Medline Plus

    Full Text Available ... or DVD. CT images of internal organs, bones, soft tissue and blood vessels typically provide greater detail than traditional x-rays, particularly of soft tissues and blood vessels. A CT scan of the ...

  4. Computed Tomography (CT) -- Head

    Medline Plus

    Full Text Available ... or DVD. CT images of internal organs, bones, soft tissue and blood vessels typically provide greater detail than traditional x-rays, particularly of soft tissues and blood vessels. CT scanning provides more detailed ...

  5. Computed Tomography (CT) -- Head

    Medline Plus

    Full Text Available ... view of the body's interior. Refinements in detector technology allow nearly all CT scanners to obtain multiple ... scanning is painless, noninvasive and accurate. A major advantage of CT is its ability to image bone, ...

  6. Computed Tomography (CT) -- Sinuses

    Medline Plus

    Full Text Available ... view of the body's interior. Refinements in detector technology allow nearly all CT scanners to obtain multiple ... scanning is painless, noninvasive and accurate. A major advantage of CT is its ability to image bone, ...

  7. Computed Tomography (CT) -- Head

    Medline Plus

    Full Text Available ... microphone. top of page How does the procedure work? In many ways CT scanning works very much ... many types of tissue as well as the lungs, bones, and blood vessels. CT examinations are fast ...

  8. Computed Tomography (CT) -- Sinuses

    Medline Plus

    Full Text Available ... microphone. top of page How does the procedure work? In many ways CT scanning works very much ... many types of tissue as well as the lungs, bones, and blood vessels. CT examinations are fast ...

  9. Cardiac CT angiography after coronary artery surgery in children using 64-slice CT scan

    Energy Technology Data Exchange (ETDEWEB)

    Marini, Davide; Agnoletti, Gabriella [Centre de Reference Malformations Cardiaques Congenitales Complexes-M3C, Universite Paris Descartes, UFR Necker-Enfants Malades, Paris (France); Brunelle, Francis [University Paris Descartes, UFR Necker-Enfants Malades, Department of Pediatric Radiology, APHP, Paris (France); Sidi, Daniel; Bonnet, Damien [Centre de Reference Malformations Cardiaques Congenitales Complexes-M3C, Universite Paris Descartes, UFR Necker-Enfants Malades, Paris (France); Ou, Phalla [Centre de Reference Malformations Cardiaques Congenitales Complexes-M3C, Universite Paris Descartes, UFR Necker-Enfants Malades, Paris (France); University Paris Descartes, UFR Necker-Enfants Malades, Department of Pediatric Radiology, APHP, Paris (France)], E-mail: phalla.ou@nck.aphp.fr

    2009-09-15

    Objective: The purpose of this study was to compare the diagnostic accuracy of 64-slice CT with that of invasive angiography in the detection of graft and/or coronary angioplasty stenosis in children who had undergone coronary artery surgery. Population and methods: Fifteen consecutive children (8 male and 7 female; age 9.2 {+-} 6.1 years) underwent 64-slice CT because of chest pain or ECG changes mean 4.8 {+-} 3.7 years after surgical coronary artery surgery; 10 patients had coronary angioplasty using a patch from the saphenous vein, four had mammary artery bypass, and one had saphenous vein bypass. Six main segments of the coronary arteries and all the bypass graft considered as a single segment were analyzed and compared with invasive angiography used as the reference standard. Results: CT correctly identified the four children with coronary angioplasty and mammary graft lesions that were confirmed by conventional angiography: one patient had a significant stenosis (>50% stenosis) at the mammary bypass graft anastomosis site; three other had non-significant stenosis (<50% stenosis) including a mild lesion of the saphenous vein patch in two patients and a mild lesion at the anastomosis site of the mammary bypass in one. All segments identified as normal by CT in the other 11 children were also found to be normal by conventional angiography. Conclusion: In centers expert in this technique, 64-slice CT scanning is a promising, rapid, and useful diagnostic technique for evaluating both coronary angioplasty and bypass graft lesions in children who had undergone coronary artery surge0008.

  10. Childhood CT scans linked to leukemia and brain cancer later in life

    Science.gov (United States)

    Children and young adults scanned multiple times by computed tomography (CT), a commonly used diagnostic tool, have a small increased risk of leukemia and brain tumors in the decade following their first scan.

  11. Interobserver variability in visual evaluation of thoracic CT scans and comparison with automatic computer measurements of CT lung density

    DEFF Research Database (Denmark)

    Wille, M.M.W.; Thomsen, Laura H.; Petersen, Jens;

    lung density measurements, i.e. densitometry. Methods – In a pilot study 60 CT scans were selected from a sample of 3980 CT scans from The Danish Lung Cancer Screening Trial (DLCST). The amount of emphysema in these scans was scored independently by two observers, who were blinded regarding clinical......Introduction – Emphysema is defined by pathology, but is most precisely evaluated in vivo by computed tomography (CT). Aims – were to determine the reproducibility of visual evaluation of emphysema, i.e. the observer variability, and furthermore to compare the visual evaluations to automatic CT...... correlation. Results – Spearman’s correlation coefficient between the two observers was r = 0.85, p < 0.001. However, the combined observations for both observers had a correlation with the CT lung density measurements of r = 0.25, p = 0.05. Conclusions – We found a high degree of interobserver consistency in...

  12. Interobserver variability in visual evaluation of thoracic CT scans and comparison with automatic computer measurements of CT lung density

    DEFF Research Database (Denmark)

    Winkler Wille, Mathilde Marie; Thomsen, Laura Hohwü; Dirksen, Asger;

    2012-01-01

    lung density measurements, i.e. densitometry. Methods – In a pilot study 60 CT scans were selected from a sample of 3980 CT scans from The Danish Lung Cancer Screening Trial (DLCST). The amount of emphysema in these scans was scored independently by two observers, who were blinded regarding clinical......Introduction – Emphysema is defined by pathology, but is most precisely evaluated in vivo by computed tomography (CT). Aims – were to determine the reproducibility of visual evaluation of emphysema, i.e. the observer variability, and furthermore to compare the visual evaluations to automatic CT...... correlation. Results – Spearman’s correlation coefficient between the two observers was r = 0.85, p < 0.001. However, the combined observations for both observers had a correlation with the CT lung density measurements of r = 0.25, p = 0.05. Conclusions – We found a high degree of interobserver consistency in...

  13. Dual-time FDG-PET/CT in patients with potential breast cancer recurrence: Head-to-head comparison with CT and bone scintigraphy

    DEFF Research Database (Denmark)

    Baun, Christina; Falch Braas, Kirsten; Gerke, Oke;

    modalities were verified by biopsy. If biopsy was impossible, a composite reference comprising all available imaging procedures and follow-up data was used as gold standard. Sensitivity, specificity, accuracy, positive and negative predictive values (PPV/NPV) and likelihood ratio of positive and negative...... to supply functional information with morphology. The literature shows that some breast carcinomas have low metabolic activity which can lead to false negatives when the study technique involves a single time-point acquisition . Several studies have demonstrated that FDG uptake continues to increase......% and 93%, respectively. The corresponding values for CT were 54% and 100%, respectively, and for bone scintigraphy 86% and 68%, respectively. On a lesion basis, sensitivity and specificity were 80% and 90% for 1-hour FDG-PET/CT and 84% and 90%, respectively, for the 3-hour scan. CT and bone scintigraphy...

  14. Skeletal idiopathic osteosclerosis helps to perform personal identification of unknown decedents: A novel contribution from anatomical variants through CT scan.

    Science.gov (United States)

    De Angelis, D; Gibelli, D; Palazzo, E; Sconfienza, L; Obertova, Z; Cattaneo, C

    2016-07-01

    Personal identification consists of the comparison of ante-mortem information from a missing person with post-mortem data obtained from an unidentified corpse. Such procedure is based on the assessment of individualizing features which may help in providing a conclusive identification between ante-mortem and post-mortem material. Anatomical variants may provide important clues to correctly identify human remains. Areas of idiopathic osteosclerosis (IO), or dense bone islands (DBIs) characterized by radiopaque areas of dense, trabeculated, non-inflamed vital bone represent one of these, potentially individualizing, anatomical features. This study presents a case where the finding of DBI was crucial for a positive identification through CT-scan. A decomposed body was found in an apartment in June 2014 in advanced decomposition and no dental records were available to perform a comparison for positive identification. Genetic tests were not applicable because of the lack of relatives in a direct line. The analysis of the only ante-mortem documentation, a CT-scan to the deceased dating back to August 2009, showed the presence of three DBIs within the trabecular bone of the proximal portion of the right femur. The same bony district was removed from the corpse during the autopsy and analysed by CT-scan, which verified the presence of the same features. Forensic practitioners should therefore be aware of the great importance of anatomical bone variants, such as dense bone islands for identification purposes, and the importance of advanced radiological technique for addressing the individualizing potential of such variants. We propose that anatomical variants of the human skeleton should be considered as being "primary identification characteristics" similar to dental status, fingerprints and DNA. PMID:27320398

  15. The value of FDG PET/CT in the initial staging and bone marrow involvement of patients with multiple myeloma

    Energy Technology Data Exchange (ETDEWEB)

    Sager, Sait; Erguel, Nurhan; Ciftci, Hediye; Cermik, Teyfik Fikret [Istanbul Education and Research Hospital, Clinic of Nuclear Medicine, Istanbul (Turkey); Cetin, Gueven; Guener, Sebnem Izmir [Istanbul Education and Research Hospital, Clinic of Internal Medicine, Istanbul (Turkey)

    2011-07-15

    The aim of this study was to describe the role of positron emission tomography/computed tomography (PET/CT) with fluorine-18 fluorodeoxyglucose (FDG) in the detection of skeletal and visceral involvement in patients with MM (multiple myeloma) at the initial diagnosis and to evaluate the relation between maximum standardized uptake values (SUVmax) of FDG with bone marrow cellularity and plasma cell ratios. The study population consisted of 42 patients (15 F, 28 M; mean {+-} SD age; 47 {+-} 12 years). Thirty-two patients were referred for initial diagnosis and ten patients were referred for assessment of therapy response. PET/CT scan was obtained 60 min after the administration of 5.4 MBq/kg FDG. The SUVmax of FDG uptake was measured from the region of interest, which was placed at the site of most prominent lesion in bone marrow in PET/CT images. Thirty patients were positive (29 of 32 initially diagnosed, one of ten previously treated) and 12 patients were negative on PET/CT scan. Conventional radiological methods were negative in three of 30 FDG PET/CT-positive patients and these methods did not show any pathological finding in 12 FDG PET/CT-negative patients. The sensitivity of FDG PET in detecting bone marrow involvement at initial diagnosis was 90%. There was a significant correlation between SUVmax values and bone marrow biopsy cellularity and plasma cell ratios, (r = 0.54 and r = 0.74, p < 0.01). The results of this study demonstrated that FDG-PET is a useful technique for the assessment of MM and the correlation between SUVmax and plasma cell ratios in bone marrow biopsy may avoid repeated bone marrow biopsies in the follow-up period. (orig.)

  16. Computed Tomography (CT) -- Sinuses

    Medline Plus

    Full Text Available ... its ability to image bone, soft tissue and blood vessels all at the same time. Unlike conventional x-rays, CT scanning provides very detailed images of many types of tissue as well as the lungs, bones, ...

  17. Computed Tomography (CT) -- Head

    Medline Plus

    Full Text Available ... its ability to image bone, soft tissue and blood vessels all at the same time. Unlike conventional x-rays, CT scanning provides very detailed images of many types of tissue as well as the lungs, bones, ...

  18. Quantification and visualization of alveolar bone resorption from 3D dental CT images

    Energy Technology Data Exchange (ETDEWEB)

    Nagao, Jiro; Mori, Kensaku; Kitasaka, Takayuki; Suenaga, Yasuhito [Nagoya University, Graduate School of Information Science, Nagoya (Japan); Yamada, Shohzoh; Naitoh, Munetaka [Aichi-Gakuin University, School of Dentistry, Nagoya (Japan)

    2007-06-15

    Purpose A computer aided diagnosis (CAD) system for quantifying and visualizing alveolar bone resorption caused by periodontitis was developed based on three-dimensional (3D) image processing of dental CT images. Methods The proposed system enables visualization and quantification of resorption of alveolar bone surrounding and between the roots of teeth. It has the following functions: (1) vertical measurement of the depth of resorption surrounding the tooth in 3D images, avoiding physical obstruction; (2) quantification of the amount of resorption in the furcation area; and (3) visualization of quantification results by pseudo-color maps, graphs, and motion pictures. The resorption measurement accuracy in the area surrounding teeth was evaluated by comparing with dentist's recognition on five real patient CT images, giving average absolute difference of 0.87 mm. An artificial image with mathematical truth was also used for measurement evaluation. Results The average absolute difference was 0.36 and 0.10 mm for surrounding and furcation areas, respectively. The system provides an intuitive presentation of the measurement results. Conclusion Computer aided diagnosis of 3D dental CT scans is feasible and the technique is a promising new tool for the quantitative evaluation of periodontal bone loss. (orig.)

  19. 18F-FDG PET/CT compared to conventional imaging modalities in pediatric primary bone tumors

    International Nuclear Information System (INIS)

    F-Fluoro-2-deoxy-d-glucose (FDG) positron emission tomography (PET) is useful in adults with primary bone tumors. Limited published data exist in children. To compare hybrid FDG positron emission tomography/computed tomography (PET/CT) with conventional imaging (CI) modalities in detecting malignant lesions, predicting response to chemotherapy and diagnosing physeal involvement in pediatric primary bone tumors. Retrospective analysis of PET/CT and CI reports with histopathology or follow-up > 6 months as reference standard. Response parameters and physeal involvement at diagnosis were compared to histopathology. A total of 314 lesions were detected in 86 scans. Excluding lung lesions, PET/CT had higher sensitivity and specificity than CI (83%, 98% and 78%, 97%, respectively). In lung lesions, PET/CT had higher specificity than CI (96% compared to 87%) but lower sensitivity (80% compared to 93%). Higher initial SUVmax and greater SUVmax reduction on PET/CT after chemotherapy predicted a good response. Change in tumor size on MRI did not predict response. Both PET/CT and MRI were very sensitive but of low specificity in predicting physeal tumor involvement. PET/CT appears more accurate than CI in detecting malignant lesions in childhood primary bone tumors, excluding lung lesions. It seems better than MRI at predicting tumor response to chemotherapy. (orig.)

  20. {sup 18}F-FDG PET/CT compared to conventional imaging modalities in pediatric primary bone tumors

    Energy Technology Data Exchange (ETDEWEB)

    London, Kevin [The Children' s Hospital at Westmead, Department of Nuclear Medicine, Sydney, NSW (Australia); University of Sydney, Discipline of Paediatrics and Child Health, Sydney Medical School, Sydney, NSW (Australia); Stege, Claudia; Kaspers, Gertjan [VU Medical Centre, Divisions of Paediatric Oncology/Haematology, Amsterdam (Netherlands); Cross, Siobhan; Dalla-Pozza, Luciano [The Children' s Hospital at Westmead, Department of Oncology, Sydney (Australia); Onikul, Ella [The Children' s Hospital at Westmead, Department of Medical Imaging, Sydney (Australia); Graf, Nicole [The Children' s Hospital at Westmead, Department of Pathology, Sydney (Australia); Howman-Giles, Robert [The Children' s Hospital at Westmead, Department of Nuclear Medicine, Sydney, NSW (Australia); University of Sydney, Discipline of Imaging, Sydney Medical School, Sydney, NSW (Australia)

    2012-04-15

    F-Fluoro-2-deoxy-d-glucose (FDG) positron emission tomography (PET) is useful in adults with primary bone tumors. Limited published data exist in children. To compare hybrid FDG positron emission tomography/computed tomography (PET/CT) with conventional imaging (CI) modalities in detecting malignant lesions, predicting response to chemotherapy and diagnosing physeal involvement in pediatric primary bone tumors. Retrospective analysis of PET/CT and CI reports with histopathology or follow-up > 6 months as reference standard. Response parameters and physeal involvement at diagnosis were compared to histopathology. A total of 314 lesions were detected in 86 scans. Excluding lung lesions, PET/CT had higher sensitivity and specificity than CI (83%, 98% and 78%, 97%, respectively). In lung lesions, PET/CT had higher specificity than CI (96% compared to 87%) but lower sensitivity (80% compared to 93%). Higher initial SUV{sub max} and greater SUV{sub max} reduction on PET/CT after chemotherapy predicted a good response. Change in tumor size on MRI did not predict response. Both PET/CT and MRI were very sensitive but of low specificity in predicting physeal tumor involvement. PET/CT appears more accurate than CI in detecting malignant lesions in childhood primary bone tumors, excluding lung lesions. It seems better than MRI at predicting tumor response to chemotherapy. (orig.)

  1. Evolving brain lesions in the follow-up CT scans 12 h after traumatic brain injury

    Institute of Scientific and Technical Information of China (English)

    Muhammad Sohail Umerani; Asad Abbas; Saqib Kamran Bakhshi; Ujala Muhammad Qasim; Salman Sharif

    2016-01-01

    Objective: To establish the frequency of evolution in CT appearance from an initial scan to a subsequent scan within 12 h and the prognostic significance of such deterioration. Methods: All patients who presented to Department of Neurosurgery, Liaquat National Hospital and Medical College with traumatic brain injury and received their CT scan within the first 4 h of injury were included in the study. Indications for repeat CT scan were: any deterioration in neurological status after the initial scan, potentially deterio-rating lesion on initial scan with or without worsening neurology, worsening neurological status after the initial CT scan findings, or no neurological improvement after initial management in patients with normal CT scan with significant head injury. This compiled with the data of 107 patients. Results: There were 67 males and 40 females. The cause of trauma of the 70%patients was road traffic accident. In 11 patients, the lesion evolved towards resorption while 32 patients had no significant changes in the subsequent CT scan. Sixty four patients showed an increase in the size of the lesion and 65.6%of them were required surgical intervention subsequently. Conclusions: In case where the initial CT scan performed within 4 h of significant head injury was not correlated with the patient's neurology, it should be repeated within 12 h.

  2. CT scanning in Australia: a report by the National Health Technology Advisory Panel

    International Nuclear Information System (INIS)

    An overview of trends in the usage of CT scanning in Australia is given and the areas of benefit and uncertainty associated with this technology are outlined. Numbers and distribution of CT units, costs of CT services, clinical applications, safety aspects and the effects of new developments are discussed. 54 refs., 5 figs., 18 tabs

  3. Incidental musculoskeletal lesions detected on abdomnopelvic CT scans: A pictorial essay

    Energy Technology Data Exchange (ETDEWEB)

    Song, Eun Jee; Ryu, Kyung Nam; Park, Ji Seon [Dept. of Radiology, Kyung Hee University Hospital, Seoul (Korea, Republic of); Jin, Wook; Park, So Young [Dept. of Radiology, Kyung Hee University Hospital at Gangdong Hospital, Seoul (Korea, Republic of)

    2015-02-15

    Various musculoskeletal findings incidentally detected on abdominopelvic computed tomography (CT) images have risen with the increasing use of abdominopelvic CT; however, it is not uncommon for radiologists to overlook the musculoskeletal system when they examine abdominopelvic CT images. Some musculoskeletal lesions may have more clinical significance than abdominopelvic lesions, although most lesions are of little to no significance. Many osseous lesions can be diagnosed using the bone window setting and reconstructed images. The purpose of this article was to review the wide variety of musculoskeletal lesions depicted on abdominopelvic CT images and to emphasize the use of the bone window setting.

  4. Total-body CT scanning in trauma patients: Benefits and boundaries

    NARCIS (Netherlands)

    J.C. Sierink

    2015-01-01

    Computed tomography (CT) scanning has become essential in the early diagnostic phase of trauma care. It is a fast and highly accurate modality for the identification of various injuries and it enables a rapid response to life-threatening problems. Especially total-body CT (TBCT) scanning is increasi

  5. CT scan in severe diffuse head injury: physiological and clinical correlations.

    OpenAIRE

    Teasdale, E; Cardoso, E.; Galbraith, S; Teasdale, G.

    1984-01-01

    CT scan findings, clinical features and intracranial pressure were studied in patients with severe diffuse head injury. Compression of the 3rd ventricle and basal cisterns closely correlated with an intracranial pressure greater than 20 mmHg, with clinical signs of midbrain dysfunctions and worse prognosis. These CT scan findings can indicate whether intracranial pressure monitoring is appropriate.

  6. Virtual teeth: a 3D method for editing and visualizing small structures in CT scans

    DEFF Research Database (Denmark)

    Bro-Nielsen, Morten; Larsen, Per; Kreiborg, Sven;

    1996-01-01

    The paper presents an interactive method for segmentation and visualization of small structures in CT scans. A combination of isosurface generation, spatial region growing and interactive graphics tools are used to extract small structures interactively. A practical example of segmentation of the...... dentition in a CT scan is shown...

  7. Attenuation and image quality in the use of protective bismuth in chest CT scans

    International Nuclear Information System (INIS)

    For chest CT scans are protective of bismuth (Bi) with the aim of reducing the dose in the breast. The aim of this study was to evaluate the attenuation with thermoluminescent dosimeters in the glandular dose average when using these protective breast CT scans and to evaluate the image quality with and without protective Bismuth.

  8. Correction of step artefact associated with MRI scanning of long bones.

    Science.gov (United States)

    Rathnayaka, Kanchana; Cowin, Gary; Schuetz, Michael A; Sahama, Tony; Schmutz, Beat

    2013-07-01

    3D models of long bones are being utilised for a number of fields including orthopaedic implant design. Accurate reconstruction of 3D models is of utmost importance to design accurate implants to allow achieving a good alignment between two bone fragments. Thus for this purpose, CT scanners are employed to acquire accurate bone data exposing an individual to a high amount of ionising radiation. Magnetic resonance imaging (MRI) has been shown to be a potential alternative to computed tomography (CT) for scanning of volunteers for 3D reconstruction of long bones, essentially avoiding the high radiation dose from CT. In MRI imaging of long bones, the artefacts due to random movements of the skeletal system create challenges for researchers as they generate inaccuracies in the 3D models generated by using data sets containing such artefacts. One of the defects that have been observed during an initial study is the lateral shift artefact occurring in the reconstructed 3D models. This artefact is believed to result from volunteers moving the leg during two successive scanning stages (the lower limb has to be scanned in at least five stages due to the limited scanning length of the scanner). As this artefact creates inaccuracies in the implants designed using these models, it needs to be corrected before the application of 3D models to implant design. Therefore, this study aimed to correct the lateral shift artefact using 3D modelling techniques. The femora of five ovine hind limbs were scanned with a 3T MRI scanner using a 3D vibe based protocol. The scanning was conducted in two halves, while maintaining a good overlap between them. A lateral shift was generated by moving the limb several millimetres between two scanning stages. The 3D models were reconstructed using a multi threshold segmentation method. The correction of the artefact was achieved by aligning the two halves using the robust iterative closest point (ICP) algorithm, with the help of the overlapping

  9. Non-invasive transcranial ultrasound therapy based on a 3D CT scan: protocol validation and in vitro results

    Energy Technology Data Exchange (ETDEWEB)

    Marquet, F; Pernot, M; Aubry, J-F; Montaldo, G; Tanter, M; Fink, M [Laboratoire Ondes et Acoustique, ESPCI, Universite Paris VII, UMR CNRS 7587, 10 rue Vauquelin, 75005 Paris (France); Marsac, L [Supersonic Imagine, Les Jardins de la Duranne, 510 rue Rene Descartes, 13857 Aix-en-Provence (France)], E-mail: fabrice.marquet@espci.org

    2009-05-07

    A non-invasive protocol for transcranial brain tissue ablation with ultrasound is studied and validated in vitro. The skull induces strong aberrations both in phase and in amplitude, resulting in a severe degradation of the beam shape. Adaptive corrections of the distortions induced by the skull bone are performed using a previous 3D computational tomography scan acquisition (CT) of the skull bone structure. These CT scan data are used as entry parameters in a FDTD (finite differences time domain) simulation of the full wave propagation equation. A numerical computation is used to deduce the impulse response relating the targeted location and the ultrasound therapeutic array, thus providing a virtual time-reversal mirror. This impulse response is then time-reversed and transmitted experimentally by a therapeutic array positioned exactly in the same referential frame as the one used during CT scan acquisitions. In vitro experiments are conducted on monkey and human skull specimens using an array of 300 transmit elements working at a central frequency of 1 MHz. These experiments show a precise refocusing of the ultrasonic beam at the targeted location with a positioning error lower than 0.7 mm. The complete validation of this transcranial adaptive focusing procedure paves the way to in vivo animal and human transcranial HIFU investigations.

  10. CT evaluation of local leakage of bone cement after percutaneous kyphoplasty and vertebroplasty

    Energy Technology Data Exchange (ETDEWEB)

    Lee, In Jae; Choi, A. Lam; Yie, Mi-Yeon; Yoon, Ji Young; Jeon, Eui Yong; Koh, Sung Hye; Yoon, Dae Young; Lim, Kyung Ja (Dept. of Radiology, Hallym Univ. Sacred Heart Hospital, Seoul (Korea)), e-mail: ijlee2003@medimail.co.kr; Im, Hyoung June (Dept. of Occupational Medicine, Hallym Univ. College of Medicine, Seoul (Korea))

    2010-07-15

    Background: Percutaneous injection of bone cement (acrylic cement) during percutaneous kyphoplasty and vertebroplasty can cause symptomatic or asymptomatic complications due to leakage, extravasation or vascular migration of cement. Purpose: To investigate and to compare the incidence and site of local leakage or complications of bone cement after percutaneous kyphoplasty and vertebroplasty using bone cement. Material and Methods: We retrospectively reviewed 473 cases of percutaneous kyphoplasty or vertebroplasty performed under fluoroscopic guidance. Of the 473 cases, follow-up CT scans that covered the treated bones were available for 83 cases (59 kyphoplasty and 24 vertebroplasty). Results: The rate of local leakage of bone cement was 87.5% (21/24) for percutaneous vertebroplasty and 49.2% (29/59) for kyphoplasty. The most common site of local leakage was perivertebral soft tissue (n=8, 38.1%) for vertebroplasty. The most common site of local leakage was a perivertebral vein (n=7, 24.1%) for kyphoplasty. Two cases of pulmonary cement embolism developed: one case after kyphoplasty and one case after vertebroplasty. Conclusion: Local leakage of bone cement was more common for percutaneous vertebroplasty compared with kyphoplasty (P<0.005). The most common sites of local leakage were perivertebral soft tissue and perivertebral vein.

  11. The diagnostic value of PET/CT scanning in patients with cervical cancer

    DEFF Research Database (Denmark)

    Loft, Annika; Berthelsen, Anne Kiil; Roed, Henrik;

    2007-01-01

    OBJECTIVE: To investigate the clinical value of PET/CT as a supplement to FIGO staging in patients with cervical cancer stage >or=1B. METHODS: This prospective study included 120 consecutive patients. After staging, a whole-body PET/CT scan was performed and these examinations were divided into two....../CT scanning for newly diagnosed cervical cancer FIGO stage >or=1B has a high sensitivity and specificity, and can be a valuable supplement to the FIGO staging procedure....

  12. Effect of Work Improvement for Promotion of Outpatient Satisfaction on CT scan

    International Nuclear Information System (INIS)

    Nowadays, most of the hospital serves 'one stop service' for CT scan. The patients could be taken the CT scan in the day they register for scan. On the contrary to the time convenience, patients are not satisfied with long waiting time and unkindness of staff. The objective of this study is to improve the patient's satisfaction for the CT scan, by analyzing inconvenience factors and improving the service qualities. From April 1 to August 30 in 2011, we investigated the satisfaction of patients who did examined abdomen CT scan with contrast media. We analyzed the 89 questionnaires before and after the service improvements from them. The worker's kindness, the environment of CT room and understanding about CT scan were answered by questionnaire and the waiting time of a day CT scan was drawn by medical information statistics. Also, the period before improvement was from April to June and the period after improvement was from July to September. And these questionnaire was analyzed through SPSS V. 15.0. In this study, kindness of staff, environment of CT room, intelligibility for CT scan and waiting time was explored and analyzed by SPSS V.15.0. The score of kindness was improved by 32%, satisfaction level of the environment was improved by 52.54%. The understanding level about CT scan was improved by 52.36% and the waiting time of a day CT was shortened by 21% through our service enhancement programs. Consequentially, it is considered that these efforts would contribute to increase the revenue of hospital.

  13. Immediate periodontal bone plate changes induced by rapid maxillary expansion in the early mixed dentition: CT findings

    Directory of Open Access Journals (Sweden)

    Daniela Gamba Garib

    2014-06-01

    Full Text Available OBJECTIVE: This study aimed at evaluating buccal and lingual bone plate changes caused by rapid maxillary expansion (RME in the mixed dentition by means of computed tomography (CT. METHODS: The sample comprised spiral CT exams taken from 22 mixed dentition patients from 6 to 9 years of age (mean age of 8.1 years presenting constricted maxillary arch treated with Haas-type expanders. Patients were submitted to spiral CT scan before expansion and after the screw activation period with a 30-day interval between T1 and T2. Multiplanar reconstruction was used to measure buccal and lingual bone plate thickness and buccal bone crest level of maxillary posterior deciduous and permanent teeth. Changes induced by expansion were evaluated using paired t test (p < 0.05. RESULTS: Thickness of buccal and lingual bone plates of posterior teeth remained unchanged during the expansion period, except for deciduous second molars which showed a slight reduction in bone thickness at the distal region of its buccal aspect. Buccal bone dehiscences were not observed in the supporting teeth after expansion. CONCLUSION: RME performed in mixed dentition did not produce immediate undesirable effects on periodontal bone tissues.

  14. Bone scans and the timing of treatment for condylar hyperplasia.

    Science.gov (United States)

    Robinson, P D; Harris, K; Coghlan, K C; Altman, K

    1990-08-01

    Bone scintiscans comparing the uptake of technetium 99 in the normal and affected condyles of 10 patients with unilateral condylar hyperplasia were recorded at or after the time when overall growth had ceased. The scans of 6 patients demonstrated persisting increased growth activity at this time. In 2 of these cases where the abnormal condyles showed uptakes of 240% and 170% with respect to the normal side, the nature and timing of treatment were changed when the results of the scans were known. PMID:2120367

  15. CT imaging of bone and bone marrow infiltration in malignant melanoma--Challenges and limitations for clinical staging in comparison to 18FDG-PET/CT.

    Science.gov (United States)

    Bier, Georg; Hoffmann, Vera; Kloth, Christopher; Othman, Ahmed E; Eigentler, Thomas; Garbe, Claus; La Fougère, Christian; Pfannenberg, Christina; Nikolaou, Konstantin; Klumpp, Bernhard

    2016-04-01

    Rationale of this study was the evaluation of the diagnostic value of computed tomography (CT) in the detection of bone marrow infiltration in comparison to PET/CT. Fifty patients (age 61 ± 15.12 years) with metastatic malignant melanoma underwent 18F-FDG-PET/CT, including contrast-enhanced CT. 2 readers evaluated the CT images in consensus for bone and bone marrow lesions focusing on lesion location, type and size. PET/CT was used as reference standard to estimate sensitivity, specificity, negative and positive predictive value. Moreover, the bone marrow density was estimated in the long bones and the sacral bone. Serum hamoglobin, thrombocyte level and S100 protein were correlated with the presence or absence of bone and bone marrow lesions. According to PET/CT as standard of reference, of 594 bone and medullary lesions 495 were considered malignant. Of these 77.8% were medullary, 20.4% lytic, 1% sclerotic and 0.8% mixed lytic/sclerotic. Contrast-enhanced CT yielded a lesion-based sensitivity of 36.8% and a specificity of 87.9% (PPV 93.8%; NPV 21.8%). Patient-based sensitivity and specificity were 78.8% and 82.4%, respectively. Of the missed lesions, most were medullary (95.8%). A disseminated bone marrow involvement (defined as >10 bone marrow lesions or diffuse infiltration of a whole body segment) was described in 11 cases, in 6 cases the disseminated involvement was underestimated or missed on CT. In cases with disseminated bone marrow involvement the bone marrow density was significantly higher in the humerus (p=0.04), but not in the femur or sacral bone (p=0.06). Multivariate analysis revealed no isolated effect of bone metastases on S100 serum and hemoglobin level, but both were significantly altered in patients with disseminated bone marrow involvement (p<0.05). In conclusion, the diagnostic value of computed tomography for the detection of bone marrow metastases in patients with melanoma, is limited. Especially in cases with disseminated bone marrow

  16. Can an abnormal CT scan be predicted from common symptoms after mild head injury in children?

    Directory of Open Access Journals (Sweden)

    Ashok Munivenkatappa

    2013-01-01

    Full Text Available Introduction: Children have non specific symptoms after mild head injury (MHI. It is difficult to define indication of CT scan among them. We aimed at identification of predictors of CT scan findings after MHI. Materials and Methods: Children aged ≤12 years with GCS 13-15 after head injury were retrospectively evaluated for their clinical and CT scan findings during January to March 2010. The variables used for detection of abnormal (positive CT scan were age, gender, cause of injury (road traffic accident, fall, and assault, loss of consciousness, vomiting, ear or nose bleed, seizure, and GCS score. Results: A total of 133 children were included in study. Sixty nine (51.9% children had abnormal CT findings. There was no statistical difference in patients with normal vs abnormal CT scan for presence of any of the variables evaluated. Conclusion: An abnormal CT scan cannot be reliably ruled out in a child with MHI based on symptoms; hence a policy of liberal CT scan based on clinical acumen is advisable.

  17. Technetium bone scanning as an aid in the diagnosis of atypical acute osteomyelitis in children

    Energy Technology Data Exchange (ETDEWEB)

    Letts, R.M.; Afifi, A.; Sutherland, J.B.

    1975-06-01

    Technetium bone scanning is a simple, safe and accurate method for the diagnosis of acute osteomyelitis in children whose presenting clinical findings are atypical of bone infection. Bone scanning was effective in the localization of the exact site of osteomyelitis, thus facilitating needle aspiration as well as subsequent surgical decompression. Technetium bone scanning is a diagnostic technique for determining bone infection in children who are unable to communicate adequately or in those whose signs have been modified by previous inadequate antibacterial therapy.

  18. Usefulness of three-phase bone scintigraphy and SPECT/CT for the diagnosis of bone lesions of systemic sarcoidosis

    Directory of Open Access Journals (Sweden)

    Shigeaki Higashiyama

    2014-05-01

    The findings of the three-phase bone scintigraphy and SPECT/CT suggested the presence of systemic sarcoidosis; however, a subsequent 18Ffluorodeoxyglucose positron emission tomography/CT (FDG-PET/CT could not exclude the possibility of multiple metastases from testicular tumors. Therefore, testicular enucleation was performed, and the pathological examination confirmed the presence of sarcoidosis.

  19. Pulmonary infections following bone marrow transplantation: High-resolution CT findings in 35 paediatric patients

    International Nuclear Information System (INIS)

    Purpose: The purpose of this study was to assess the high-resolution CT findings of paediatric patients who had pulmonary infections following bone marrow transplantation (BMT), and to evaluate the differential diagnosis through high-resolution CT of the various pathogens responsible for pulmonary infections after BMT. Patients and methods: The study included 35 consecutive patients who had documented pulmonary infection, high-resolution CT of the chest performed within 24 h of the beginning of symptoms, and proven diagnosis within 1 week of the onset of symptoms. The pulmonary infections were due to viruses (n = 16), bacteria (n = 9), fungi (n = 9), and protozoa (n = 1). Two radiologists analyzed the CT scans and reached final decisions regarding the findings by consensus. Results: Four patients with confirmed pneumonia had normal high-resolution CT scans. Regarding the viral infections, the most frequent features were areas of ground-glass attenuation (43.7%) and small centrilobular nodules (31.2%). Airspace consolidation (88.9%), small centrilobular nodules (22.2%) and ground-glass attenuation (22.2%) were the most frequent findings in patients with bacterial pneumonia following BMT. Large nodules were seen in 66.7% of the patients with fungal pneumonia, and in only one case of virus infection. The 'halo sign' (n = 5) was seen only in patients with fungal pneumonia. Conclusion: In conclusion, the main causes of pulmonary infection in paediatric patients following BMT share similar high-resolution CT findings. Large nodules and 'halo sign' are more common in patients with fungal infections

  20. Pulmonary infections following bone marrow transplantation: High-resolution CT findings in 35 paediatric patients

    Energy Technology Data Exchange (ETDEWEB)

    Davaus Gasparetto, Taisa [Department of Diagnostic Radiology of the Federal Universitie Fluminense, Niteroi (Brazil); Federal University of Rio de Janeiro, Rio de Janeiro (Brazil)], E-mail: taisadavaus@gmail.com; Escuissato, Dante L. [Department of Diagnostic Radiology of the University of Parana, Curitiba (Brazil); Marchiori, Edson [Department of Diagnostic Radiology of the Federal Universitie Fluminense, Niteroi (Brazil); Federal University of Rio de Janeiro, Rio de Janeiro (Brazil)

    2008-04-15

    Purpose: The purpose of this study was to assess the high-resolution CT findings of paediatric patients who had pulmonary infections following bone marrow transplantation (BMT), and to evaluate the differential diagnosis through high-resolution CT of the various pathogens responsible for pulmonary infections after BMT. Patients and methods: The study included 35 consecutive patients who had documented pulmonary infection, high-resolution CT of the chest performed within 24 h of the beginning of symptoms, and proven diagnosis within 1 week of the onset of symptoms. The pulmonary infections were due to viruses (n = 16), bacteria (n = 9), fungi (n = 9), and protozoa (n = 1). Two radiologists analyzed the CT scans and reached final decisions regarding the findings by consensus. Results: Four patients with confirmed pneumonia had normal high-resolution CT scans. Regarding the viral infections, the most frequent features were areas of ground-glass attenuation (43.7%) and small centrilobular nodules (31.2%). Airspace consolidation (88.9%), small centrilobular nodules (22.2%) and ground-glass attenuation (22.2%) were the most frequent findings in patients with bacterial pneumonia following BMT. Large nodules were seen in 66.7% of the patients with fungal pneumonia, and in only one case of virus infection. The 'halo sign' (n = 5) was seen only in patients with fungal pneumonia. Conclusion: In conclusion, the main causes of pulmonary infection in paediatric patients following BMT share similar high-resolution CT findings. Large nodules and 'halo sign' are more common in patients with fungal infections.

  1. Optimized Temporal Window for Detection and Characterization of Renal Cell Carcinomas with Dynamic CT Scanning

    Institute of Scientific and Technical Information of China (English)

    Jinhong Wang; Peijun Wang; Xiaohu Zhao; Xinqin Mao; Xiaolong Gao; Jun Liu

    2005-01-01

    OBJECTIVE To investigate the optimized time period for detection and characterization of renal cell carcinomas (RCC) when the specific CT features appear during spiral dynamic CT scanning, and to optimize an effective scanning protocol of spiral CT for evaluating RCC.METHODS Twenty-four patients with RCC verified by pathology had undergone a dynamic CT (D-CT) scan. A plain scan was employed to select the target slice. Single-level dynamic scanning started at 14-17 s after the intravenous contrast media had been administered, with a scan interval of 4.9 s acquiring a total number of 17~24 frames. A regular CT scan of the whole kidney followed by a delayed single slice acquisition through the target slice in the excretory phase was performed. Images were assessed in two ways: (1) A group of experienced radiologists reviewed the CT images to find when the specific signs appeared and when the CT features of RCC were optimally displayed; (2) Data measurement of the time-density curves (T-DC) of RCC. The exact time was obtained when the densities of the tumor, renal parenchyma, medulla and aorta reached their peak enhancement, thus also the time when the density difference between tumor and parenchyma was at maximum (Max T-M). Based on the slope of the contrast media uptake curve, T-DC types were ranked from the smallest to the biggest of slope as type A, B and C.RESULTS 1. The review of the CT images by the radiologists showed that the CT features of RCC were optimally demonstrated at 70.2 s. The earliest time at which RCC CT features were examined was at 23.9 s. 2. Image data analysis: the time that the density (or CT value) of the tumor mass reached peak enhancement was at 54 s and peak value was at 80.4 Hu for RCC. The time of the maximal difference of densities between tumor and renal parenchyma was at 102 s.CONCLUSION The following proposal is the scanning protocol for detecting RCC recommended by our research: After a plain scan to determine the target level, a

  2. The value of baseline CT head scans in the assessment of shunt complications in hydrocephalus

    Energy Technology Data Exchange (ETDEWEB)

    Cantrell, P. (Alder Hey Children' s Hospital, Liverpool (United Kingdom)); Fraser, F. (Alder Hey Children' s Hospital, Liverpool (United Kingdom)); Pilling, D. (Alder Hey Children' s Hospital, Liverpool (United Kingdom)); Carty, H. (Alder Hey Children' s Hospital, Liverpool (United Kingdom))

    1993-10-01

    The purpose of this study was to determine the value of a baseline CT head scan in the assessment of patients who subsequently presented with symptoms which may have been due to shunt complications (such as blockage or infection). In all these patients the shunt had been inserted in the treatment of hydrocephalus. We conclude that the presence of a baseline scan does not add to the interpretation of CT scans done when the patient presents with symptoms of possible shunt malfunction. (orig.)

  3. Role of F-18 FDG PET/CT in assessing bone marrow involvement in pediatric Hodgkin's lymphoma

    International Nuclear Information System (INIS)

    The aim of the current study was to assess the utility of F-18-fluoro-2-deoxy-D-glucose (F-18 FDG) positron emission tomography/computed tomography (PET/CT) in assessing bone marrow involvement (BMI) compared to bone marrow biopsy (BMB) in initial staging of Hodgkin's lymphoma (HL) in pediatric patients. Data of 38 pediatric patients (mean age 9.8 years, range 3-18 years) with HL were analyzed for the involvement of bone marrow. All patients underwent non-contrast F-18 FDG PET/CT study. BMB was done in 31 patients from the bilateral iliac crests. Scans were interpreted by two nuclear medicine physicians blinded to the details of BMB. Of the 31 patients who underwent BMB, 5 patients had lymphomatous involvement on BMB. PET/CT was positive in four of these five patients. In 26 patients negative on BMB, PET was negative in 23 patients and positive in 3 patients for BMI. The sensitivity and negative predictive value of F-18 FDG PET/CT was 87.5 and 96%, respectively, for BMI. F-18 FDG PET/CT can predict BMB results with high accuracy. F-18 FDG PET/CT may be used at initial staging of pediatric Hodgkin's lymphoma as it uncovers unsuspected BMI and BMB may be omitted in patients with PET-positive BMI. (author)

  4. Comparison of FDG-PET/CT and bone scintigraphy for detection of bone metastases in breast cancer

    Energy Technology Data Exchange (ETDEWEB)

    Hahn, Steffen; Heusner, Till; Forsting, Michael; Antoch, Gerald (Dept. of Diagnostic and Interventional Radiology and Neuroradiology, Univ. Hospital Essen, Univ. Duisburg-Essen, Essen (Germany)), email: steffen.hahn@uk-essen.de; Kuemmel, Sherko; Koeninger, Angelika (Dept. of Gynecology and Obstetrics, Univ. Hospital Essen, Univ. Duisburg-Essen, Essen (Germany)); Nagarajah, James; Mueller, Stefan; Boy, Christian; Bockisch, Andreas; Stahl, Alexander (Dept. of Nuclear Medicine, Univ. Hospital Essen, Univ. Duisburg-Essen, Essen (Germany))

    2011-11-15

    Background Bone scintigraphy is the standard procedure for the detection of bone metastases in breast cancer patients. FDG-PET/CT has been reported to be a sensitive tool for tumor staging in different malignant diseases. However, its accuracy for the detection of bone metastases has not been compared to bone scintigraphy. Purpose To compare whole-body FDG-PET/CT and bone scintigraphy for the detection of bone metastases on a lesion basis in breast cancer patients. Material and Methods Twenty-nine consecutive women (mean age 58 years, range 35-78 years) with histologically proven breast cancer were assessed with bone scintigraphy and whole-body FDG-PET/CT. Twenty-one patients (72%) were suffering from primary breast cancer and eight patients (28%) were in aftercare with a history of advanced breast cancer. Both imaging procedures were assessed for bone metastases by a radiologist and a nuclear medicine physician. Concordant readings between bone scintigraphy and FDG-PET/CT were taken as true. Discordant readings were verified with additional MRI imaging in all patients and follow-up studies in most patients. Results A total of 132 lesions were detected on bone scintigraphy, FDG-PET/CT or both. According to the reference standard, 70/132 lesions (53%) were bone metastases, 59/132 lesions (45%) were benign, and three lesions (2%) remained unclear. The sensitivity of bone scintigraphy was 76% (53/70) compared to 96% (67/70) for FDG-PET/CT. The specificity of bone scintigraphy and FDG-PET/CT was 95% (56/59) and 92% (54/59), respectively. According to the reference standard bone metastases were present in eight out of the 29 patients (28%), whereas 20 patients (69%) were free of bone metastases. One (3%) patient had inconclusive readings on both modalities as well as on MRI and follow-up studies. Bone scintigraphy and FDG-PET/CT correctly identified seven out of eight patients with bone metastases and 20 out of 20 patients free of metastases. Conclusion On a lesion

  5. Scan Quality and Entrance Skin Dose in Thoracic CT: A Comparison between Bismuth Breast Shield and Posteriorly Centered Partial CT Scans

    International Nuclear Information System (INIS)

    Objectives. To compare the effectiveness of the bismuth breast shield and partial CT scan in reducing entrance skin dose and to evaluate the effect of the breast shield on image quality (IQ). Methods. Nanodots were placed on an adult anthropomorphic phantom. Standard chest CT, CT with shield, and partial CT were performed. Nanodot readings and effective doses were recorded. 50 patients with chest CTs obtained both with and without breast shields were reviewed. IQ was evaluated by two radiologists and by measuring Hounsfield units (HUs) and standard deviation (SD) of HU in anterior subcutaneous region. Results. Breast shield and the partial CT scans reduced radiation to the anterior chest by 38% and 16%, respectively. Partial CT increased dose to the posterior chest by 37% and effective dose by 8%. Change in IQ in shield CT was observed in the anterior chest wall. Significant change in IQ was observed in 5/50 cases. The shield caused an increase of 20 HU (P = 0.021) and a 1.86 reduction in SD of HU (P = 0.027) in the anterior compared to posterior subcutaneous regions. Summary. Bismuth breast shield is more effective than the partial CT in reducing entrance skin dose while maintaining image quality

  6. Biopsy versus FDG PET/CT in the initial evaluation of bone marrow involvement in pediatric lymphoma patients

    International Nuclear Information System (INIS)

    The objective is to assess the role of 18F-2-fluoro-2-deoxy-D-glucose (FDG) positron emission tomography (PET)/CT versus bone marrow biopsy (BMB) in the initial evaluation of bone marrow (BM) involvement in pediatric lymphoma patients. Fifty-four pediatric patients with pathologically proven lymphoma [31 Hodgkin's disease (HD), 23 non-Hodgkin's lymphoma (NHL)] were included in this study. All patients had soft tissue biopsy and BMB and had FDG PET/CT scans within 2 weeks of biopsy. Among the 31 HD patients, FDG PET/CT revealed positive BM involvement in 4 patients, while BMB revealed BM involvement in 2 patients who were also positive on FDG PET/CT imaging. Among the 23 NHL patients, FDG PET/CT revealed positive BM involvement in 8 patients, while biopsy revealed BM involvement in 5 patients on initial studies (4 of them were also positive on FDG PET/CT, and 1 was BMB positive but was negative on FDG PET/CT), plus 1 false-negative BMB study initially but positive on repeat biopsy after FDG PET/CT. The overall sensitivity of detecting BM involvement by lymphoma was 92 and 54% (p < 0.05) for FDG PET/CT and BMB, respectively. It is noted that there were more positive BMB findings in patients with abnormal FDG activities seen in the biopsy sites on PET/CT. Our study demonstrates that FDG PET/CT has high sensitivity and accuracy and a substantial complementary value to BMB in the initial diagnosis of pediatric lymphoma, and should be employed as a first-line study. (orig.)

  7. Biopsy versus FDG PET/CT in the initial evaluation of bone marrow involvement in pediatric lymphoma patients

    Energy Technology Data Exchange (ETDEWEB)

    Cheng, Gang; Chamroonrat, Wichana; Torigian, Drew A.; Alavi, Abass [Hospital of the University of Pennsylvania, Department of Radiology, Philadelphia, PA (United States); Chen, Wengen [University of Maryland Medical Center, Department of Diagnostic Radiology and Nuclear Medicine, Baltimore, MD (United States); Zhuang, Hongming [Children' s Hospital of Philadelphia, Philadelphia, PA (United States)

    2011-08-15

    The objective is to assess the role of {sup 18}F-2-fluoro-2-deoxy-D-glucose (FDG) positron emission tomography (PET)/CT versus bone marrow biopsy (BMB) in the initial evaluation of bone marrow (BM) involvement in pediatric lymphoma patients. Fifty-four pediatric patients with pathologically proven lymphoma [31 Hodgkin's disease (HD), 23 non-Hodgkin's lymphoma (NHL)] were included in this study. All patients had soft tissue biopsy and BMB and had FDG PET/CT scans within 2 weeks of biopsy. Among the 31 HD patients, FDG PET/CT revealed positive BM involvement in 4 patients, while BMB revealed BM involvement in 2 patients who were also positive on FDG PET/CT imaging. Among the 23 NHL patients, FDG PET/CT revealed positive BM involvement in 8 patients, while biopsy revealed BM involvement in 5 patients on initial studies (4 of them were also positive on FDG PET/CT, and 1 was BMB positive but was negative on FDG PET/CT), plus 1 false-negative BMB study initially but positive on repeat biopsy after FDG PET/CT. The overall sensitivity of detecting BM involvement by lymphoma was 92 and 54% (p < 0.05) for FDG PET/CT and BMB, respectively. It is noted that there were more positive BMB findings in patients with abnormal FDG activities seen in the biopsy sites on PET/CT. Our study demonstrates that FDG PET/CT has high sensitivity and accuracy and a substantial complementary value to BMB in the initial diagnosis of pediatric lymphoma, and should be employed as a first-line study. (orig.)

  8. 11C-choline vs. 18F-FDG PET/CT in assessing bone involvement in patients with multiple myeloma

    Directory of Open Access Journals (Sweden)

    Ambrosini Valentina

    2007-06-01

    Full Text Available Abstract Background Multiple Myeloma (MM is a B cell neoplasm causing lytic or osteopenic bone abnormalities. Whole body skeletal survey (WBSS, Magnetic resonance (MR and 18F-FDG PET/CT are imaging techniques routinely used for the evaluation of bone involvement in MM patients. Aim As MM bone lesions may present low 18F-FDG uptake; the aim of this study was to assess the possible added value and limitations of 11C-Choline to that of 18F-FDG PET/CT in patients affected with MM. Methods Ten patients affected with MM underwent a standard 11C-Choline PET/CT and an 18F-FDG PET/CT within one week. The results of the two scans were compared in terms of number, sites and SUVmax of lesions. Results Four patients (40% had a negative concordant 11C-Choline and 18F-FDG PET/CT scans. Two patients (20% had a positive 11C-Choline and 18F-FDG PET/CT scans that identified the same number and sites of bone lesions. The remaining four patients (40% had a positive 11C-Choline and 18F-FDG PET/CT scan, but the two exams identified different number of lesions. Choline showed a mean SUVmax of 5 while FDG showed a mean SUVmax of 3.8 (P = 0.042. Overall, 11C-Choline PET/CT scans detected 37 bone lesions and 18F-FDG PET/CT scans detected 22 bone lesions but the difference was not significant (P = 0.8. Conclusion According to these preliminary data, 11C-Choline PET/CT appears to be more sensitive than 18F-FDG PET/CT for the detection of bony myelomatous lesions. If these data are confirmed in larger series of patients, 11C-Choline may be considered a more appropriate functional imaging in association with MRI for MM bone staging.

  9. Dental CT and orthodontic implants: imaging technique and assessment of available bone volume in the hard palate

    International Nuclear Information System (INIS)

    Purpose: Palatal implants (PI) have been introduced for orthodontic treatment of dental and skeletal dysgnathia. Due to the restricted amount of bone in this region, precise preoperative anatomic information is necessary. The aim of this study was to determine whether dental CT could serve as a tool to locate the optimal size and position for orthodontic implant placement. Materials and methods: In 32 patients, where palatal implant placement was planned, axial CT scans of the maxillary bone were acquired. Using a standard dental software package (Easy Vision dental software package 2.1, Philips; Best, The Netherlands), paracoronal views were reconstructed and measurements of palatal bone height in 3 mm increments, dorsally from the incisive canal, were performed in the median and both paramedian regions. Results: The overall mean bone height was 5.01 mm (S.D. 2.60), ranging from 0 to 16.9 mm. The maximum palatal bone height was 6.17 mm (S.D. 2.81) at 6 mm dorsally from the incisive canal. Due to the lack of adequate bone (less than 4 mm), implant placement was not performed in 3 cases (7%). In the remaining 39 cases (93.0%), primary implant stability was achieved and complications, such as perforation of the palate, could be avoided. Conclusion: The results demonstrate that dental CT promises to be a valuable tool in evaluating the potential and optimal size and site for orthodontic implant placement

  10. Dental CT and orthodontic implants: imaging technique and assessment of available bone volume in the hard palate

    Energy Technology Data Exchange (ETDEWEB)

    Gahleitner, Andre E-mail: andre.gahleitner@univie.ac.at; Podesser, Birgit; Schick, Susanne; Watzek, Georg; Imhof, Herwig

    2004-09-01

    Purpose: Palatal implants (PI) have been introduced for orthodontic treatment of dental and skeletal dysgnathia. Due to the restricted amount of bone in this region, precise preoperative anatomic information is necessary. The aim of this study was to determine whether dental CT could serve as a tool to locate the optimal size and position for orthodontic implant placement. Materials and methods: In 32 patients, where palatal implant placement was planned, axial CT scans of the maxillary bone were acquired. Using a standard dental software package (Easy Vision dental software package 2.1, Philips; Best, The Netherlands), paracoronal views were reconstructed and measurements of palatal bone height in 3 mm increments, dorsally from the incisive canal, were performed in the median and both paramedian regions. Results: The overall mean bone height was 5.01 mm (S.D. 2.60), ranging from 0 to 16.9 mm. The maximum palatal bone height was 6.17 mm (S.D. 2.81) at 6 mm dorsally from the incisive canal. Due to the lack of adequate bone (less than 4 mm), implant placement was not performed in 3 cases (7%). In the remaining 39 cases (93.0%), primary implant stability was achieved and complications, such as perforation of the palate, could be avoided. Conclusion: The results demonstrate that dental CT promises to be a valuable tool in evaluating the potential and optimal size and site for orthodontic implant placement.

  11. Magnification bone scan of knees for knee pain evaluation

    International Nuclear Information System (INIS)

    Knee pain is one of the common complaints of patients seen in our orthopedic clinic. Routine anterior and posterior views of whole body bone scan (WBBS) is often not sufficient in the evaluation of these patients. An ideal bone scan using pinhole collimator or single photon emission tomography (SPECT), however, is impractical and time consuming in busy nuclear medicine department with limited resources. Therefore, the aim of the study is to assess limited bone scan of knees with magnification (LNSKM) for knee pain evaluation. Technical aspect of LBSKM and diagnostic efficacy are discussed on this poster. Adult patients with knee pain were reffered for LBSKM from an orthopedic surgen specializing knees. Four hundred fifteen LBSKMs were performed since 1999. patients were given 740 MBq (20mCi) Tc-99m MDP intravenously and 3 hours later LBSKM was performed using a low energy high resolution parallel hole collimator and Siemens Orbitor camera. (Simens medical systems. Inc., Hoffman Estates, III., USA). Anterior view of the knees was taken for 5 min, without magnification and both lateral views of symptomatic knees were obtained with electronic magnification (1.25, upto 2.0) for 8 min each. Disease processes such as DJD, traumatic arthritis, P-F tendonitis, SONK, meniscus tear are detected and illustrated along with normal knee scan finding. We believe LBSKM may not be as good as SPECT or pinhole imaging of the knees in the evaluation of knee pain but superior to routine WBBS in the nuclear medicine department with limited resources of instrumentation and manpower

  12. Patient dose estimation from CT scans at the Mexican National Neurology and Neurosurgery Institute

    Science.gov (United States)

    Alva-Sánchez, Héctor; Reynoso-Mejía, Alberto; Casares-Cruz, Katiuzka; Taboada-Barajas, Jesús

    2014-11-01

    In the radiology department of the Mexican National Institute of Neurology and Neurosurgery, a dedicated institute in Mexico City, on average 19.3 computed tomography (CT) examinations are performed daily on hospitalized patients for neurological disease diagnosis, control scans and follow-up imaging. The purpose of this work was to estimate the effective dose received by hospitalized patients who underwent a diagnostic CT scan using typical effective dose values for all CT types and to obtain the estimated effective dose distributions received by surgical and non-surgical patients. Effective patient doses were estimated from values per study type reported in the applications guide provided by the scanner manufacturer. This retrospective study included all hospitalized patients who underwent a diagnostic CT scan between 1 January 2011 and 31 December 2012. A total of 8777 CT scans were performed in this two-year period. Simple brain scan was the CT type performed the most (74.3%) followed by contrasted brain scan (6.1%) and head angiotomography (5.7%). The average number of CT scans per patient was 2.83; the average effective dose per patient was 7.9 mSv; the mean estimated radiation dose was significantly higher for surgical (9.1 mSv) than non-surgical patients (6.0 mSv). Three percent of the patients had 10 or more brain CT scans and exceeded the organ radiation dose threshold set by the International Commission on Radiological Protection for deterministic effects of the eye-lens. Although radiation patient doses from CT scans were in general relatively low, 187 patients received a high effective dose (>20 mSv) and 3% might develop cataract from cumulative doses to the eye lens.

  13. Patient dose estimation from CT scans at the Mexican National Neurology and Neurosurgery Institute

    Energy Technology Data Exchange (ETDEWEB)

    Alva-Sánchez, Héctor, E-mail: halva@ciencias.unam.mx [Unidad de Imagen Molecular PET/CT, Instituto Nacional de Neurología y Neurocirugía Manuel Velasco Suárez, Insurgentes Sur 3877 Col. La Fama, 14269, México D.F. (Mexico); Reynoso-Mejía, Alberto [Unidad de Imagen Molecular PET/CT, Instituto Nacional de Neurología y Neurocirugía Manuel Velasco Suárez, Insurgentes Sur 3877 Col. La Fama, 14269, México D.F., Mexico and Departamento de Neuroimagen, Instituto Nacional de (Mexico); Casares-Cruz, Katiuzka; Taboada-Barajas, Jesús [Departamento de Neuroimagen, Instituto Nacional de Neurología y Neurocirugía Manuel Velasco Suárez, Insurgentes Sur 3877 Col. La Fama, 14269, México D.F. (Mexico)

    2014-11-07

    In the radiology department of the Mexican National Institute of Neurology and Neurosurgery, a dedicated institute in Mexico City, on average 19.3 computed tomography (CT) examinations are performed daily on hospitalized patients for neurological disease diagnosis, control scans and follow-up imaging. The purpose of this work was to estimate the effective dose received by hospitalized patients who underwent a diagnostic CT scan using typical effective dose values for all CT types and to obtain the estimated effective dose distributions received by surgical and non-surgical patients. Effective patient doses were estimated from values per study type reported in the applications guide provided by the scanner manufacturer. This retrospective study included all hospitalized patients who underwent a diagnostic CT scan between 1 January 2011 and 31 December 2012. A total of 8777 CT scans were performed in this two-year period. Simple brain scan was the CT type performed the most (74.3%) followed by contrasted brain scan (6.1%) and head angiotomography (5.7%). The average number of CT scans per patient was 2.83; the average effective dose per patient was 7.9 mSv; the mean estimated radiation dose was significantly higher for surgical (9.1 mSv) than non-surgical patients (6.0 mSv). Three percent of the patients had 10 or more brain CT scans and exceeded the organ radiation dose threshold set by the International Commission on Radiological Protection for deterministic effects of the eye-lens. Although radiation patient doses from CT scans were in general relatively low, 187 patients received a high effective dose (>20 mSv) and 3% might develop cataract from cumulative doses to the eye lens.

  14. Patient dose estimation from CT scans at the Mexican National Neurology and Neurosurgery Institute

    International Nuclear Information System (INIS)

    In the radiology department of the Mexican National Institute of Neurology and Neurosurgery, a dedicated institute in Mexico City, on average 19.3 computed tomography (CT) examinations are performed daily on hospitalized patients for neurological disease diagnosis, control scans and follow-up imaging. The purpose of this work was to estimate the effective dose received by hospitalized patients who underwent a diagnostic CT scan using typical effective dose values for all CT types and to obtain the estimated effective dose distributions received by surgical and non-surgical patients. Effective patient doses were estimated from values per study type reported in the applications guide provided by the scanner manufacturer. This retrospective study included all hospitalized patients who underwent a diagnostic CT scan between 1 January 2011 and 31 December 2012. A total of 8777 CT scans were performed in this two-year period. Simple brain scan was the CT type performed the most (74.3%) followed by contrasted brain scan (6.1%) and head angiotomography (5.7%). The average number of CT scans per patient was 2.83; the average effective dose per patient was 7.9 mSv; the mean estimated radiation dose was significantly higher for surgical (9.1 mSv) than non-surgical patients (6.0 mSv). Three percent of the patients had 10 or more brain CT scans and exceeded the organ radiation dose threshold set by the International Commission on Radiological Protection for deterministic effects of the eye-lens. Although radiation patient doses from CT scans were in general relatively low, 187 patients received a high effective dose (>20 mSv) and 3% might develop cataract from cumulative doses to the eye lens

  15. Is It Possible to Predict Heart Rate and Range during Enhanced Cardiac CT Scan from Previous Non-enhanced Cardiac CT?

    OpenAIRE

    Horiguchi, Jun; Yamamoto, Hideya; Arie, Ryuichi; Kiguchi, Masao; Fujioka, Chikako; Ohtaki, Megu; Kihara, Yasuki; Awai, Kazuo

    2010-01-01

    The effect of heart rate and variation during cardiac computed tomography (CT) on the examination quality. The purpose of this study is to investigate whether it is possible to predict heart rate and range during enhanced cardiac computed CT scan from previous non-enhanced cardiac CT scan. Electrocardiograph (ECG) files from 112 patients on three types of cardiac 64-slice CT (non-enhanced, prospective ECG-triggered and retrospective ECG-gated enhanced scans) were recorded. The mean heart rate...

  16. Influence of scan setting selections on root canal visibility with cone beam CT

    NARCIS (Netherlands)

    B.A. Hassan; J. Payam; B. Juyanda; P. van der Stelt; P.R. Wesselink

    2012-01-01

    Objectives The aim of this study was to assess the influence of scan setting selection, including field of view (FOV) ranging from small to large, number of projections and scan modes on the visibility of the root canal with cone beam CT (CBCT). Methods One human mandible cadaver was scanned with CB

  17. Brain tumors and CT scan in infants and children, (1). The impact on pediatric neuroradiology

    Energy Technology Data Exchange (ETDEWEB)

    Ohi, S.; Velasco, J.M. (Northwestern Univ., Chicago, IL (USA). Medical School)

    1980-10-01

    The dramatic change in the neuroradiological procedures have been noted after CT scan was introduced in the last several years. Remarkable decreasing numbers of angiographic, pneumoencephalographic and other invasive neuroradiologic studies as well as nuclear brain scan were also found in the pediatric neuroradiology. The authors analyzed the total numbers of these studies performed in the last several years in pediatric neurological/neurosurgical practice in the light of the impact of CT scan especially in the diagnostic procedures and treatments of brain tumor in children. Although the number of these procedures decreased up to 49% in plain skull X-ray, 54% in cerebral angiography, 70% in pneumoencephalography/ventriculography and 79% in nuclear brain scan after CT scan was installed in our results, it is extremely important to renew understanding of those characteristics in each special procedures. Cerebral angiography as well as pneumoencephalography may give the surgeon more precise ideas of the anatomical relationship between the lesion and other normal structures, especially in the posterior fossa tumor in which CT scan occassionally demonstrates only a gross finding. A case with false negative result and another case with a complicated anatomical structure in CT scan were presented. The significance of cerebral angiography and other invasive studies in the diagnosis and follow up of brain tumor in CT scan were discussed.

  18. The frequency of brain lesion on CT scan in traumatic pediatric that referred to Ayatollah Taleghani Hospital of Kermanshah 2011

    OpenAIRE

    Salehi Zahabi, Saleh; Mehrbakhsh, Mahmmod; Salehi Zahabi, Kharaman; Asgari, Shahriar; Darabi, Shahnaz; Ahmadi, Karam

    2012-01-01

    Abstract: Background: Brain trauma (BT) is the most common cause of death among children worldwide. In traumatic patient, the skull is the most common involved part. The importance of computed tomography (CT) scan in diagnosis of BT is well established. CT scan is actually a common option for evaluation of patients with cranial trauma. Considering the importance of CT scan in the diagnosis of brain lesions, the present study was aimed to survey the results of brain CT scan in traumatic patien...

  19. Increase in dicentric chromosome formation after a single CT scan in adults

    OpenAIRE

    Yu Abe; Tomisato Miura; Yoshida, Mitsuaki A.; Risa Ujiie; Yumiko Kurosu; Nagisa Kato; Atsushi Katafuchi; Naohiro Tsuyama; Takashi Ohba; Tomoko Inamasu; Fumio Shishido; Hideyoshi Noji; Kazuei Ogawa; Hiroshi Yokouchi; Kenya Kanazawa

    2015-01-01

    Excess risk of leukemia and brain tumors after CT scans in children has been reported. We performed dicentric chromosome assay (DCAs) before and after CT scan to assess effects of low-dose ionizing radiation on chromosomes. Peripheral blood (PB) lymphocytes were collected from 10 patients before and after a CT scan. DCA was performed by analyzing either 1,000 or 2,000 metaphases using both Giemsa staining and centromere-fluorescence in situ hybridization (Centromere-FISH). The increment of DI...

  20. Estimating the lifetime risk of cancer associated with multiple CT scans

    International Nuclear Information System (INIS)

    Multiple CT scans are often done on the same patient resulting in an increased risk of cancer. Prior publications have estimated risks on a population basis and often using an effective dose. Simply adding up the risks from single scans does not correctly account for the survival function. A methodology for estimating personal radiation risks attributed to multiple CT imaging using organ doses is presented in this article. The estimated magnitude of the attributable risk fraction for the possible development of radiation-induced cancer indicates the necessity for strong clinical justification when ordering multiple CT scans. (paper)

  1. Value of CT scan in the diagnosis of primary large bowel lymphoma

    Institute of Scientific and Technical Information of China (English)

    赵修义; 张雪林; 王劲; 郑卫权; 文戈

    2003-01-01

    Objective:To study the CT imaging of primary large bowel lymphoma and evaluate the value of CT scan.Methods:CT reports of 8 patients with proven primary large bowel lymphoma were retrospectively reviewed.Plain CT scans were done on all patients,enhanced CT scans simultaneously with 5 - 10 mm section thickness,and 5 - 10 mm table increments in 6 cases.Results:Primary involved sites were on the cecum(n = 3),the ascending colon(n = 2),and the rectum(n = 1).The tumor was found in multiple areas of the large bowel in 2 cases.CT appearance fell into 3 typical patterns in our study.The first was focal mass type in 2 cases,with one combined with intussusception and retroperitoneal adenopathy; the second was segmental annular involvement type in 3 cases,with one of them combined with mesenteric adenopathy; the last was diffuse involvement type in 2 cases.Multiple nodules were seen in the rectum in 1 case.Conclusion:CT was found to be accurate in detecting the primary sites and complications of lymphoma,and evaluating invasion of adjacent structures; Focal mass type,segmental annular involvement type and diffuse involvement type are the main patterns of CT features in the primary large bowel lymphoma; The features revealed by CT scan are suggestive of primary large bowel lymphoma in some cases.

  2. Acquiring 4D thoracic CT scans using a multislice helical method

    International Nuclear Information System (INIS)

    Respiratory motion degrades anatomic position reproducibility during imaging, necessitates larger margins during radiotherapy planning and causes errors during radiation delivery. Computed tomography (CT) scans acquired synchronously with the respiratory signal can be used to reconstruct 4D CT scans, which can be employed for 4D treatment planning to explicitly account for respiratory motion. The aim of this research was to develop, test and clinically implement a method to acquire 4D thoracic CT scans using a multislice helical method. A commercial position-monitoring system used for respiratory-gated radiotherapy was interfaced with a third generation multislice scanner. 4D cardiac reconstruction methods were modified to allow 4D thoracic CT acquisition. The technique was tested on a phantom under different conditions: stationary, periodic motion and non-periodic motion. 4D CT was also implemented for a lung cancer patient with audio-visual breathing coaching. For all cases, 4D CT images were successfully acquired from eight discrete breathing phases, however, some limitations of the system in terms of respiration reproducibility and breathing period relative to scanner settings were evident. Lung mass for the 4D CT patient scan was reproducible to within 2.1% over the eight phases, though the lung volume changed by 20% between end inspiration and end expiration (870 cm3). 4D CT can be used for 4D radiotherapy, respiration-gated radiotherapy, 'slow' CT acquisition and tumour motion studies

  3. CT scanning analysis of Megantereon whitei (Carnivora, Machairodontinae) from Monte Argentario (Early Pleistocene, central Italy): evidence of atavistic teeth

    Science.gov (United States)

    Iurino, Dawid Adam; Sardella, Raffaele

    2014-12-01

    CT scanning analysis applied to vertebrate palaeontology is providing an increasing number of data of great interest. This method can be used in many branches of palaeontology such as the investigation of all the fossilized elements in a hard matrix and the hidden structures in the bones. A large number of pathologies are "hidden", completely or partially invisible on the external surface of the bones because their development took place within the bones. However, the study of these diseases and abnormalities plays a crucial role in our understanding of evolutionary and adaptive processes of extinct taxa. The analysis of a partial skeleton of the sabre-toothed felid Megantereon whitei from the Early Pleistocene karst filling deposits of Monte Argentario (Tuscany, Italy) has been carried out. The CT scanning analysis put in evidence the presence of supernumerary teeth (P2) and the absence of P3 in the mandible. The occurrence of P2 can be considered as an evidence of atavism. Such an archaic feature is recorded for the first time in Megantereon.

  4. Estimated radiation exposure and cancer risk from CT and PET/CT scans in patients with lymphoma

    International Nuclear Information System (INIS)

    Introduction: The purpose of this study was to estimate total effective dose and cancer risk related to treatment monitoring and surveillance computed tomography (CT) scans in a cohort of patients diagnosed with lymphoma. Methods: 76 patients with head, neck, chest, abdomen or pelvis CT and whole-body positron emission tomography (PET)/CT were identified from an institutional lymphoma database; this included 54 (71%) patients with non-Hodgkin and 22 (29%) patients with classical Hodgkin lymphoma. Average treatment and surveillance periods were 8 months (range, 3–14 mo) and 23 months (range, 1–40 mo), respectively. Radiation exposure was estimated from the dose-length product (DLP) for CT scans and milli-Curies and DLP for PET/CT scans. Cancer risk was estimated using the Biological Effects of Ionizing Radiation model. Results: During their treatment period, 45 patients had 161 CT exams and 39 patients had 73 PET/CT exams. Mean effective dose was 39.3 mSv (range, 7.1–100 mSv). During the surveillance period, 60 patients had 378 CT exams and 25 patients had 39 PET/CT exams. Mean effective dose was 53.2 mSv (range, 2.6–154 mSv). Seventeen of 76 (22.4%) patients had total cumulative doses greater than 100 mSv. The mean increase in estimated cancer risk was 0.40%; the greatest estimated risk to any one patient was 1.19%. Conclusion: Mean total effective dose and mean estimated cancer risk were low in patients with lymphoma undergoing serial imaging, suggesting that theoretical risks of radiation-induced cancer need not be a major consideration in radiologic follow-up

  5. Estimated radiation exposure and cancer risk from CT and PET/CT scans in patients with lymphoma

    Energy Technology Data Exchange (ETDEWEB)

    Guttikonda, Ravi [Imaging Institute, Cleveland Clinic, 9500 Euclid Avenue, Cleveland, OH 44195 (United States); Herts, Brian R., E-mail: hertsb@ccf.org [Imaging Institute, Cleveland Clinic, 9500 Euclid Avenue, Cleveland, OH 44195 (United States); Taussig Cancer Institute, Cleveland Clinic, 9500 Euclid Avenue, Cleveland, OH 44195 (United States); Dong, Frank [Imaging Institute, Cleveland Clinic, 9500 Euclid Avenue, Cleveland, OH 44195 (United States); Baker, Mark E. [Imaging Institute, Cleveland Clinic, 9500 Euclid Avenue, Cleveland, OH 44195 (United States); Taussig Cancer Institute, Cleveland Clinic, 9500 Euclid Avenue, Cleveland, OH 44195 (United States); Fenner, Kathleen B.; Pohlman, Brad [Taussig Cancer Institute, Cleveland Clinic, 9500 Euclid Avenue, Cleveland, OH 44195 (United States)

    2014-06-15

    Introduction: The purpose of this study was to estimate total effective dose and cancer risk related to treatment monitoring and surveillance computed tomography (CT) scans in a cohort of patients diagnosed with lymphoma. Methods: 76 patients with head, neck, chest, abdomen or pelvis CT and whole-body positron emission tomography (PET)/CT were identified from an institutional lymphoma database; this included 54 (71%) patients with non-Hodgkin and 22 (29%) patients with classical Hodgkin lymphoma. Average treatment and surveillance periods were 8 months (range, 3–14 mo) and 23 months (range, 1–40 mo), respectively. Radiation exposure was estimated from the dose-length product (DLP) for CT scans and milli-Curies and DLP for PET/CT scans. Cancer risk was estimated using the Biological Effects of Ionizing Radiation model. Results: During their treatment period, 45 patients had 161 CT exams and 39 patients had 73 PET/CT exams. Mean effective dose was 39.3 mSv (range, 7.1–100 mSv). During the surveillance period, 60 patients had 378 CT exams and 25 patients had 39 PET/CT exams. Mean effective dose was 53.2 mSv (range, 2.6–154 mSv). Seventeen of 76 (22.4%) patients had total cumulative doses greater than 100 mSv. The mean increase in estimated cancer risk was 0.40%; the greatest estimated risk to any one patient was 1.19%. Conclusion: Mean total effective dose and mean estimated cancer risk were low in patients with lymphoma undergoing serial imaging, suggesting that theoretical risks of radiation-induced cancer need not be a major consideration in radiologic follow-up.

  6. The use of CT-scanning at the medicolegal external postmortem examination and at the forensic autopsy

    DEFF Research Database (Denmark)

    Leth, Peter Mygind

    2006-01-01

    Introduction: Can CT-scanning of deceased at the medico legal external examination improve the selection of cases to autopsy? Is CT-scanning a substitute or a supplement to the traditional forensic autopsy? Material: In 2006 60 deceased individuals from Southern Denmark (counties of Fyn and Sønde......Introduction: Can CT-scanning of deceased at the medico legal external examination improve the selection of cases to autopsy? Is CT-scanning a substitute or a supplement to the traditional forensic autopsy? Material: In 2006 60 deceased individuals from Southern Denmark (counties of Fyn...... and Sønderjylland) (15 females and 45 males) were CT-scanned before autopsy. Method: A double-blind prospective investigation of CT-scanning in autopsy cases. A multislice spiral CT-scanner (Siemens Somatom Spirit) was used. Data from the CT-scanning and the autopsy were registered in a computer database...

  7. Optimization of the scan protocols for CT-based material extraction in small animal PET/CT studies

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Ching-Ching [Department of Medical Imaging and Radiological Sciences, Tzu Chi College of Technology, 880, Sec 2, Chien-Kuo Rd., Hualien, Taiwan (China); Yu, Jhih-An [Department of Biomedical Imaging and Radiological Sciences, National Yang-Ming University, 155 Li-Nong St., Sec. 2, Taipei, Taiwan (China); Yang, Bang-Hung [Department of Biomedical Imaging and Radiological Sciences, National Yang-Ming University, 155 Li-Nong St., Sec. 2, Taipei, Taiwan (China); Department of Nuclear Medicine, Taipei Veterans General Hospital, Taipei, Taiwan (China); Wu, Tung-Hsin, E-mail: tung@ym.edu.tw [Department of Biomedical Imaging and Radiological Sciences, National Yang-Ming University, 155 Li-Nong St., Sec. 2, Taipei, Taiwan (China)

    2013-12-11

    We investigated the effects of scan protocols on CT-based material extraction to minimize radiation dose while maintaining sufficient image information in small animal studies. The phantom simulation experiments were performed with the high dose (HD), medium dose (MD) and low dose (LD) protocols at 50, 70 and 80 kV{sub p} with varying mA s. The reconstructed CT images were segmented based on Hounsfield unit (HU)-physical density (ρ) calibration curves and the dual-energy CT-based (DECT) method. Compared to the (HU;ρ) method performed on CT images acquired with the 80 kV{sub p} HD protocol, a 2-fold improvement in segmentation accuracy and a 7.5-fold reduction in radiation dose were observed when the DECT method was performed on CT images acquired with the 50/80 kV{sub p} LD protocol, showing the possibility to reduce radiation dose while achieving high segmentation accuracy.

  8. Heart region segmentation from low-dose CT scans: an anatomy based approach

    Science.gov (United States)

    Reeves, Anthony P.; Biancardi, Alberto M.; Yankelevitz, David F.; Cham, Matthew D.; Henschke, Claudia I.

    2012-02-01

    Cardiovascular disease is a leading cause of death in developed countries. The concurrent detection of heart diseases during low-dose whole-lung CT scans (LDCT), typically performed as part of a screening protocol, hinges on the accurate quantification of coronary calcification. The creation of fully automated methods is ideal as complete manual evaluation is imprecise, operator dependent, time consuming and thus costly. The technical challenges posed by LDCT scans in this context are mainly twofold. First, there is a high level image noise arising from the low radiation dose technique. Additionally, there is a variable amount of cardiac motion blurring due to the lack of electrocardiographic gating and the fact that heart rates differ between human subjects. As a consequence, the reliable segmentation of the heart, the first stage toward the implementation of morphologic heart abnormality detection, is also quite challenging. An automated computer method based on a sequential labeling of major organs and determination of anatomical landmarks has been evaluated on a public database of LDCT images. The novel algorithm builds from a robust segmentation of the bones and airways and embodies a stepwise refinement starting at the top of the lungs where image noise is at its lowest and where the carina provides a good calibration landmark. The segmentation is completed at the inferior wall of the heart where extensive image noise is accommodated. This method is based on the geometry of human anatomy and does not involve training through manual markings. Using visual inspection by an expert reader as a gold standard, the algorithm achieved successful heart and major vessel segmentation in 42 of 45 low-dose CT images. In the 3 remaining cases, the cardiac base was over segmented due to incorrect hemidiaphragm localization.

  9. Synchrotron μCT Imaging of Bone, Titanium implants and Bone Substitutes -a Systematic Review of the Literature

    DEFF Research Database (Denmark)

    Neldam, Camilla Albeck; Pinholt, Else Marie

    2014-01-01

    to synchrotron sources (SRμCT) a spatial resolution up to one tenth of a μm may be achieved. A review of the literature concerning SRμCT was performed to investigate its usability and its strength in visualizing fine bone structures, vessels, and microarchitecture of bone. Although mainly limited to in vitro...... examinations, SRμCT is considered as a gold standard to image trabecular bone microarchitecture since it is possible in a 3D manner to visualize fine structural elements within mineralized tissue such as osteon boundaries, rods and plates structures, cement lines, and differences in mineralization...

  10. An Effort to Develop an Algorithm to Target Abdominal CT Scans for Patients After Gastric Bypass.

    Science.gov (United States)

    Pernar, Luise I M; Lockridge, Ryan; McCormack, Colleen; Chen, Judy; Shikora, Scott A; Spector, David; Tavakkoli, Ali; Vernon, Ashley H; Robinson, Malcolm K

    2016-10-01

    Abdominal CT (abdCT) scans are frequently ordered for Roux-en-Y gastric bypass (RYGB) patients presenting to the emergency department (ED) with abdominal pain, but often do not reveal intra-abdominal pathology. We aimed to develop an algorithm for rational ordering of abdCTs. We retrospectively reviewed our institution's RYGB patients presenting acutely with abdominal pain, documenting clinical and laboratory data, and scan results. Associations of clinical parameters to abdCT results were examined for outcome predictors. Of 1643 RYGB patients who had surgery between 2005 and 2015, 355 underwent 387 abdCT scans. Based on abdCT, 48 (12 %) patients required surgery and 86 (22 %) another intervention. No clinical or laboratory parameter predicted imaging results. Imaging decisions for RYGB patients do not appear to be amenable to a simple algorithm, and patient work-up should be based on astute clinical judgment.

  11. CT muscle scanning in the evaluation of patients with spinal muscular atrophy (SMA)

    Energy Technology Data Exchange (ETDEWEB)

    Sambrook, P.; Rickards, D.; Cumming, W.J.K.

    1988-12-01

    One hundred with spinal muscular atrophy (SMA) were assessed by CT scanning using a standardised technique. The spectrum of CT abnormality occurring in SMA was observed and by overall analysis the patients were divided into 4 groups. While the CT appearances of these groups correlated well with clinical assessment of severity of disease, the disease process was usually much more widespread than clinical examination suggested. CT abnormality was first observed in the leg and gluteal muscles, progressing to the posterior spinal, thigh, shoulder girdle and sternomastoid muscles. Hypertrophy of sartorius and gracilis was observed in a significant number of patients. Fascial planes were preserved in involved muscles in over half of the patients, even in late-stage disease. Asymmetrical muscle involvement was seen with increasing frequency as the disease process increased in extent as evaluated by CT scanning. There was no discernible difference in the CT appearances in those patients who clinically had limb-girdle, facioscapulohumeral or scapuloperoneal distribution of weakness.

  12. Multicentic primary angiosarcoma of bone mimicking metastasis on {sup 18}F-FDG PET/CT in a patient with a history of sigmoid colon cancer: A case report

    Energy Technology Data Exchange (ETDEWEB)

    Yoo, Min Young; Kim, Seok Ki; Park, Seog Yun; Kwon, Young Mee; Yun, Tak; Kim, Tae Sung [National Cancer Center, Goyang (Korea, Republic of); Lee, Eun Seong [Dept. of Nuclear Medicine, Chung Ang University Hospital, Seoul (Korea, Republic of)

    2015-12-15

    Primary angiosarcoma of the bone (PAB) is a rare and fatal high-grade malignant vascular bone tumor. We report a rare case of multicentric PAB mimicking bone metastasis in a 59-year-old female patient with a history of sigmoid colon cancer. This patient complained of lower back and pelvic pain and presented with multiple osteolytic bone lesions on plain radiography and pelvic computed tomography. First, bone metastasis of sigmoid colon cancer was suspected. However, on the {sup 18}F-fluorodeoxyglucose ({sup 18}F-FDG) positron emission tomography/computed tomography (PET/CT) scan, the patient presented unusual multiple hypermetabolic osteolytic bone lesions involving contiguous bones of the lower half of the body. After bone biopsy, these lesions were confirmed to be multicentric PAB. To the best of our knowledge, this is the first case report of an {sup 18}F-FDG PET/CT scan in a patient with multicentric primary bone angiosarcoma.

  13. The diagnostic value of monoclonal antibody scan (leucoscan) compared with 99mTc MDP bone scan and Ga 67 in diagnosing bone and joint infection

    International Nuclear Information System (INIS)

    Full text: Nowadays different radiopharmaceuticals have been developed as 99mTc MDP, 67Ga citrate, 111In oxine- and 99mTc HMPAO labeled leucocytes for the accurate localization of bone/joint infection, but all of them have limitations that encouraged the search of new agents characterized from high and early uptake in infectious/inflammatory tissues, low toxicity and no accumulation in non inflamed tissues. The purpose of this study is to compare the diagnostic value of a 99mTc labeled antigranulocyte Fab' fragment (Leucoscan) with 99mTc MDP bone scan and 67 Ga. The monoclonal antibody, Leucoscan, is an IgG murine Fab' fragment directed against a NCA-90 epitope located on the surface of granulocytes. 45 patients with suspected bone and joint infection (18 total hip prosthesis, 4 knee prosthesis, 8 vertebral infection and 15 long bones) were included in this study. All patients underwent conventional Rx, bone scan, 67Ga scan and Leucoscan. Three phase 99mTc MDP bone scan and 67Ga scan were performed using standard procedures. For Leucoscan the antibody was labeled with 25 mCi of 99mTc and was infected intravenously over 30 seconds. Ten minutes planar images were taken 1 h and 2 hrs p.i using a GE Millennium γ camera provided with a LEGP collimator. Images were evaluated as score 1 (no abnormal uptake), score 2 (probably positive), score 3 (definitely infected) according the intensity of abnormally increased uptake. Results were compared with 99mTc MDP bone scan and 67Ga scans. The final diagnosis was given by the surgical verification with histopathology or culture. All 45 patients had pathologic proof of presence/absence of bone and joint infection. 36/45 were positive for bone or joint infection and 9/45 were negative.30/36 patients with surgically proven bone and joint infection had true positive Leucoscan, 26/36 had true positive MDP bone scan and 20/36 true positive 67Ga scan. Nine out of 9 patients with proven absence of inflammation had true negative

  14. A low density area along the ventricular catheter on CT scan

    Energy Technology Data Exchange (ETDEWEB)

    Suzuki, Yasuo; Ishii, Ryoji; Watanabe, Akira; Hirano, Kazuhiro; Kamada, Masaki; Okamura, Hironari (Kawasaki Medical School, Kurashiki, Okayama (Japan))

    1990-12-01

    Ten patients with hydrocephalus due to various causes, such as subarachnoid or intraventricular hemorrhage, had low density area (LDA) along the ventricular catheter on CT scans. This is an analysis of the 10 patients, with a discussion of the etiology. Ventriculoperitoneal (VS) shunt was performed in 8 patients, and 3 underwent ventricular drainage. None of the patients had postoperative hemorrhage. According to CT findings, the patients were divided into three groups. The first group consisted of 3 patients whose CT scans showed progressive ventricular dilatation and a presence of LDA along the ventricular catheter. After surgical resolution of high intraventricular pressure, repeated CT scans showed a remarkably decreased ventricles and LDA. In this group, an increased intraventricular pressure may play an important role in the formation of LDA. In the second group consisting of 3 patients, there was no postoperative CT evidence of progressive ventricular dilatation, but LDA was present. Follow-up CT scans revealed a decreased lesion. A slightly increased intraventricular pressure may result in LDA. In the last group of 4 patients, CT scans showed a small, irregular, marginal LDA along the ventricular catheter, with no evidence of increased ventricle. On repeated CT scans after conservative treatment, the lesion persisted for several years after VP shunt. There was a good correlation between CT findings and patient age. Children seemed to have a large porencephalic cyst. In conclusion, LDA may be an accumulation of CSF within the unresisting white matter along the ventricular catheter due to increased intraventricular pressure. Various CT patterns seem to depend on the increased degree of intraventricular pressure and the compliance of the surrounding white matter. (N.K.).

  15. Comparison of outcomes of bone scan, clinical judgement and other imaging modalities in the pre-operative assessment of mandibular invasion by squamous cell carcinoma of oral cavity

    International Nuclear Information System (INIS)

    The squamous cell carcinoma of the oral cavity frequently involved mandible, necessitating surgical excision. To maximally preserve the mandible an accurate preoperative assessment is critical. In order to determine the relative accuracy of various investigative modalities, we compared clinical judgement, orthopantomography, computed tomography and bone scanning against decalcified mandibular histopathology as 'gold standard.' Thirty-three patients (18 males and 15 females, aged between 19 and 66 years with an average age of 53) with a previously untreated primary squamous cell carcinoma of the oral cavity underwent surgery at our Institute. In nineteen patients marginal, in 8 segmental and in 6 hemimandibulectomy was performed, based on clinical judgements. All patients had undergone pre-operative evaluation with orthopantomography, computed tomography and Tc-99m MDP bone scanning. Post-surgical histopathology revealed that 10 patients (30%) had positive evidence of mandibular involvement. Compared to histopathology the accuracy of clinical judgement, OPG, CT scan and bone scan were 64%, 73%, 88% and 88%, respectively. The sensitivity and specificity of clinical judgement, orthopantomography, computed tomography and bone scan were 90 and 52%, 40 and 87%, 70 and 96% and 100 and 83% respectively. There was no false negative bone scan. The study concluded that judicious use of clinical judgement and bone scanning can guide the surgeon in making decisions regarding mandibular excision in majority of cases of squamous cell carcinoma of the oral cavity. Negative bone scan virtually rules out mandibular invasion of the disease and more conservative surgery can be planned in these cases.(author)

  16. Acquisition, preprocessing, and reconstruction of ultralow dose volumetric CT scout for organ-based CT scan planning

    Energy Technology Data Exchange (ETDEWEB)

    Yin, Zhye, E-mail: yin@ge.com; De Man, Bruno [Image Reconstruction Laboratory, GE Global Research, Niskayuna, New York 12309 (United States); Yao, Yangyang; Wu, Mingye [X-ray and CT Laboratory, GE Global Research, Shanghai 201203 (China); Montillo, Albert [Biomedical Image Processing Laboratory, GE Global Research, Niskayuna, New York 12309 (United States); Edic, Peter M. [CT, X-ray and Functional Imaging, GE Global Research, Niskayuna, New York 12309 (United States); Kalra, Mannudeep [Thoracic and Cardiac Imaging, Massachusetts General Hospital, Boston, Massachusetts 02114 (United States)

    2015-05-15

    Purpose: Traditionally, 2D radiographic preparatory scan images (scout scans) are used to plan diagnostic CT scans. However, a 3D CT volume with a full 3D organ segmentation map could provide superior information for customized scan planning and other purposes. A practical challenge is to design the volumetric scout acquisition and processing steps to provide good image quality (at least good enough to enable 3D organ segmentation) while delivering a radiation dose similar to that of the conventional 2D scout. Methods: The authors explored various acquisition methods, scan parameters, postprocessing methods, and reconstruction methods through simulation and cadaver data studies to achieve an ultralow dose 3D scout while simultaneously reducing the noise and maintaining the edge strength around the target organ. Results: In a simulation study, the 3D scout with the proposed acquisition, preprocessing, and reconstruction strategy provided a similar level of organ segmentation capability as a traditional 240 mAs diagnostic scan, based on noise and normalized edge strength metrics. At the same time, the proposed approach delivers only 1.25% of the dose of a traditional scan. In a cadaver study, the authors’ pictorial-structures based organ localization algorithm successfully located the major abdominal-thoracic organs from the ultralow dose 3D scout obtained with the proposed strategy. Conclusions: The authors demonstrated that images with a similar degree of segmentation capability (interpretability) as conventional dose CT scans can be achieved with an ultralow dose 3D scout acquisition and suitable postprocessing. Furthermore, the authors applied these techniques to real cadaver CT scans with a CTDI dose level of less than 0.1 mGy and successfully generated a 3D organ localization map.

  17. 4D CT scan Generation of Lung from Physical Simulation of Pulmonary Motion

    OpenAIRE

    Villard, Pierre-Frédéric; Beuve, Michaël; Shariat, Behzad

    2006-01-01

    International audience Cancer ionising treatments need accurate tumour targeting, which is difficult for lung cancer due to breathing motions. We propose here to provide physicians with generated 3D + time lung CT scan from a computer graphics simulation.

  18. Few CT Scan Abnormalities Found Even in Neurologically Impaired Learning Disabled Children.

    Science.gov (United States)

    Denckla, Martha Bridge; And Others

    1985-01-01

    Most of 32 learning disabled children (seven to 14 years old) with neurological lateralization characteristics marked by right and left hemispheres had a normal CT (computerized tomography) scan. (CL)

  19. Concepts and analyses in the CT scanning of root systems and leaf canopies: A timely summary

    Directory of Open Access Journals (Sweden)

    Jonathan A Lafond

    2015-12-01

    Full Text Available Non-medical applications of computed tomography (CT scanning have flourished in recent years, including in Plant Science. This Perspective article on CT scanning of root systems and leaf canopies is intended to be of interest to three categories of readers: those who have not yet tried plant CT scanning, and should find inspiration for new research objectives; readers who are on the learning curve with applications – here is helpful advice for them; and researchers with greater experience – the field is evolving quickly and it is easy to miss aspects. Our conclusion is that CT scanning of roots and canopies is highly demanding in terms of technology, multidisciplinarity and big-data analysis, to name a few areas of expertise, but eventually, the reward for researchers is directly proportional!

  20. Coronal CT scan of paranasal sinuses; Long survey after Caldwell-Luc operation

    Energy Technology Data Exchange (ETDEWEB)

    Ikeda, Atsuko (Tokyo Metropolitan Komagome Hospital (Japan)); Ikeda, Motohisa; Watanabe, Isamu; Komatsuzaki, Atsushi

    1994-03-01

    The clinical features were correlated with the coronal CT scan appearance of the paranasal sinuses of 49 patients who had received the Caldwell-Luc operation 16 to 58 years ago. The clinical diagnosis at the time of the CT scan was postoperative maxillary cyst in 22 patients, chronic sinusitis in 21 patients, trigeminal neuralgia in 3 patients, radicular cyst, postoperative ethmoid cyst and inverted papilloma in one patient each. The CT scans of the 91 operated maxillary sinuses showed obliterated cavity in 21 cases, small cavity in 46 cases, and cystic formation in 24 cases. The authors speculated that some maxillary sinuses which appeared in CT scans as small cavities might cause the clinical symptoms of postoperative maxillary cyst in the future. (author).

  1. Micro computed tomography (CT) scanned anatomical gateway to insect pest bioinformatics

    Science.gov (United States)

    An international collaboration to establish an interactive Digital Video Library for a Systems Biology Approach to study the Asian citrus Psyllid and psyllid genomics/proteomics interactions is demonstrated. Advances in micro-CT, digital computed tomography (CT) scan uses X-rays to make detailed pic...

  2. The presence and progression of emphysema in COPD as determined by CT scanning and biomarker expression

    DEFF Research Database (Denmark)

    Coxson, Harvey O; Dirksen, Asger; Edwards, Lisa D;

    2013-01-01

    Emphysema is a key contributor to airflow limitation in chronic obstructive pulmonary disease (COPD) and can be quantified using CT scanning. We investigated the change in CT lung density in a longitudinal, international cohort of patients with COPD. We also explored the potential relation betwee...

  3. Application of multi-detector row helical scanning to postmyelographic CT

    International Nuclear Information System (INIS)

    The advent of a multi-detector row helical CT has made it possible to attain images over a broader area with good spatial resolution. We assessed whether postmyelographic CT scans obtained using this system provided more information than conventional imaging techniques. Postmyelographic CT scans were preoperatively obtained in 46 patients using a multi-detector row helical CT system. Reconstructed images in the sagittal and coronal planes in all patients and curved reformation images along the dural sac in 37 patients were compared with myelograms and conventional postmyelographic CT scans. In 34 patients comparison was also made with MR images. The multi-detector row CT images demonstrated deformities of the dural sac more clearly than the other modalities in 39 of the 46 patients. They also provided the best visualization of nerve root abnormalities in 24 of the 46 patients and clearly revealed the presence of spurs in all 22 patients with spinal canal stenosis. Postmyelographic CT scans made using a multi-detector row helical CT system provide more information on the dural sac, nerve sleeves, and their contents than other imaging techniques. (orig.)

  4. Patient-centered clinical impact of incidentally detected abnormalities on chest CT scans

    Directory of Open Access Journals (Sweden)

    Sherine G. Moftah

    2014-09-01

    Conclusion: The clinically significant different incidental abnormalities on chest CT scans represented 10.4% of all incidental findings, 3.3% were due to malignancies. The clinical impact of incidental abnormalities on chest CT may be of utmost importance on patient care.

  5. MicroCT evaluation of bone mineral density loss in human bones

    Energy Technology Data Exchange (ETDEWEB)

    Nogueira, Liebert P.; Braz, Delson; Lopes, Ricardo T. [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil). Coordenacao dos Programas de Pos-graduacao de Engenharia (COPPE). Lab. de Instrumentacao Nuclear]. E-mails: lnogueira@con.ufrj.br; Barroso, Regina C.; Oliveira, Luis F. [Universidade do Estado do Rio de Janeiro (UERJ), Rio de Janeiro, RJ (Brazil). Inst. de Fisica]. E-mail: cely@uerj.br

    2007-07-01

    Bone is a connective tissue largely composed of an organic protein, collagen and the inorganic mineral hydroxyapatite [Ca{sub 10}(PO{sub 4}){sub 6}OH{sub 2}], which combine to provide a mechanical and supportive role in the body. Depending on the orientation of collagen fibers, two types of bone can be distinguished: trabecular and cortical bone. Degree of mineralization is considered an important feature of bone quality. Changes in the degree of mineralization is generally due to osteoporosis, but many recent studies have already shown that alterations in degree of mineralization can occur due to a large variety of factors. The transmission X-ray microtomography is one of the most popular methods, which provides the spatial distribution of the total absorption coefficient inside the sample. The aim of this study was to investigate the suitability of using microCT as a supplementary tool for the diagnosis of the health status of human bones. Eleven samples were constructed simulating the physiological range of bone mineral density (BMD) found in cortical human bone. The samples represent healthy mixtures of swine compact bone dried at room temperature, powdered and mixed with fat (0 - 100 % by mass). The samples were imaged by a microfocus tube (Fein-Focus) with focal size of about 60 {mu}m ({+-}5%), and a CCD camera (0.143 mm pixel size) coupled with an intensifier tube with fluoroscope screen at the Nuclear Instrumentation Laboratory (COPPE/UFRJ), Brazil. The images were reconstructed and treated with suitable software developed at the Nuclear Instrumentation Laboratory. The mineral content in cortical bone is defined by the volume of dry, fat-free bone per unit bulk volume of the bone. The volumes were calculated from the bone density using the relationship between volume and density. The densities of fat and bone were taken to be 0.95 g.cm{sup -3} and 1.92 g.cm{sup -3} respectively. The correlation of the measured absorption coefficient with the mineral content

  6. SPECT/CT bone scintigraphy to evaluate low back pain in young athletes: common and uncommon etiologies.

    Science.gov (United States)

    Matesan, M; Behnia, F; Bermo, M; Vesselle, H

    2016-01-01

    Low back pain of various etiologies is a common clinical presentation in young athletes. In this article, we discuss the utility of SPECT/CT bone scintigraphy for the evaluation of low back pain in young athletes. The spectrum of lower spine lesions caused by sports injuries and identifiable on bone scan is presented along with strategies to avoid unnecessary irradiation of young patients. Also covered are pitfalls in diagnosis due to referred-pain phenomenon and normal skeletal variants specific to this age group. PMID:27387155

  7. Role of computed tomography (CT scan in staging of cervical carcinoma

    Directory of Open Access Journals (Sweden)

    T V Prasad

    2014-01-01

    Full Text Available Background & objectives: Staging of cervical carcinoma is done clinically using International Federation of Obstetrics and Gynecology (FIGO guidelines. It is based on physical examination findings and also includes results of biopsy, endoscopy and conventional radiological tests like chest radiograph, intravenous urography and barium enema. These conventional radiological investigations have largely been replaced by computed tomography (CT and magnetic resonance imaging (MRI at present. FIGO staging system does not consider CT and MRI mandatory; however, use of these modalities are encouraged. This prospective study was conducted to determine the role of CT in staging work up in women diagnosed with cervical carcinoma. Methods: Fifty three women diagnosed with cervical carcinoma were evaluated with contrast enhanced CT scan of abdomen and pelvis. CT scan images were especially evaluated to determine tumour size, invasion of parmetrium, pelvic walls, rectum, urinary bladder and ureters, pelvic or retroperitoneal lymphadenopathy and distant metastases. CT findings were associated with clinical findings and staging, including findings from cystoscopy and sigmoidoscopy. Results: There was a poor agreement between clinical and CT staging of cervical carcinoma. Primary tumour was demonstrated on CT in 36 (70% of 53 patients. CT underestimated the parametrial, vaginal and pelvic wall invasion when compared with physical examination. CT overestimated the urinary bladder and rectal invasion when compared with cysto-sigmoidoscopy, however, CT had 100 per cent negative predictive value (NPV to exclude bladder and rectal involvement. CT detection of lymph node enlargement and lung metastases influenced the management. Interpretation & conclusions: Our findings show that CT scan does not reliably correlate with clinical FIGO staging of cervical cancer. However, it can detect urinary obstruction as well as nodal or distant metastases and thus improves the

  8. Frequency, Causes, and Findings of Brain CT Scans of Neonatal Seizure at Besat Hospital, Hamadan, Iran

    OpenAIRE

    EGHBALIAN, Fateme; Rasuli, Bahman; MONSEF, Farnaz

    2015-01-01

    How to Cite This Article: Eghbalian F, Rasuli B, Monsef F. Frequency, Causes, and Findings of Brain CT Scans of Neonatal Seizure at Besat Hospital, Hamadan, Iran. Iran J Child Neurol. 2015 Winter;9(1):56-63.AbstractObjectiveNeonatal seizures are the most common neurological symptoms and often signal an underlying serious neurologic condition. This study determines the frequency of neonatal seizure, predisposing factors, and brain computed tomography (CT) scan findings.Materials & MethodsI...

  9. CT assessment of the correlation between clinical examination and bone involvement in oral malignant tumors

    Energy Technology Data Exchange (ETDEWEB)

    Albuquerque, Marco Antonio Portela; Oliveira, Ilka Regina Souza; Cavalcanti, Marcelo Gusmao Paraiso [Universidade de Sao Paulo (USP), SP (Brazil). Faculdade de Odontologia. Dept. de Radiologia], e-mail: mgpcaval@usp.br; Kuruoshi, Marcia Etsuko [Universidade de Sao Paulo (USP), SP (Brazil). Hospital Universitario. Dept. de Radiologia

    2009-07-01

    Oral cancers have a tendency to invade the surrounding bone structures, and this has a direct influence on the treatment management and on outcomes. The objective of this study was to correlate the clinical parameters (location, clinical presentation and TNM staging) of oral malignant tumors that can be associated with a potential of bone invasion and determine the accuracy of clinical examination to predict bone involvement, using computed tomography (CT). Twenty five patients, with oral malignant tumors were submitted to clinical and CT examinations. CT was considered the standard parameter to evaluate the presence of bone involvement. Clinical assessment of location, presentation form and TNM staging of the tumors were then compared to the CT findings in predicting bone involvement. Bone involvement was observed in 68% of the cases. It was predicted that tumors located in the retromolar trigone and hard palate, with a clinical aspect of infiltrative ulcer or nodule and classified in stage IV had a high potential to cause bone involvement. The clinical examination assessment of these tumors showed to be a valuable tool to predict bone invasion, with high sensitivity (82%) and specificity (87.5%), based on the results found in the CT images. No statistical significance was found between the CT and clinical examinations regarding bone involvement. The identification of some clinical parameters such as location, clinical presentation, and TNM stage, associated with a detailed clinical examination, was considered a valuable tool for the assessment of bone destruction by oral malignant tumors. (author)

  10. Independent measurement of femoral cortical thickness and cortical bone density using clinical CT.

    Science.gov (United States)

    Treece, G M; Gee, A H

    2015-02-01

    The local structure of the proximal femoral cortex is of interest since both fracture risk, and the effects of various interventions aimed at reducing that risk, are associated with cortical properties focused in particular regions rather than dispersed over the whole bone. Much of the femoral cortex is less than 3mm thick, appearing so blurred in clinical CT that its actual density is not apparent in the data, and neither thresholding nor full-width half-maximum techniques are capable of determining its width. Our previous work on cortical bone mapping showed how to produce more accurate estimates of cortical thickness by assuming a fixed value of the cortical density for each hip. However, although cortical density varies much less over the proximal femur than thickness, what little variation there is leads to errors in thickness measurement. In this paper, we develop the cortical bone mapping technique by exploiting local estimates of imaging blur to correct the global density estimate, thus providing a local density estimate as well as more accurate estimates of thickness. We also consider measurement of cortical mass surface density and the density of trabecular bone immediately adjacent to the cortex. Performance is assessed with ex vivo clinical QCT scans of proximal femurs, with true values derived from high resolution HRpQCT scans of the same bones. We demonstrate superior estimation of thickness than is possible with alternative techniques (accuracy 0.12 ± 0.39 mm for cortices in the range 1-3mm), and that local cortical density estimation is feasible for densities >800 mg/cm(3).

  11. Vascular anomalies, sutures and small canals of the temporal bone on axial CT

    Energy Technology Data Exchange (ETDEWEB)

    Koesling, Sabrina [Department of Diagnostic Radiology, University of Halle, E. Grube Str. 40, 06097 Halle (Germany)]. E-mail: sabrina.koesling@medizin.uni-halle.de; Kunkel, Petra [Department of Diagnostic Radiology, University of Leipzig (Germany); Schul, Thomas [Department of Diagnostic Radiology, University of Leipzig (Germany)

    2005-06-01

    Purpose: Subtle bony structures, small canals and fine sutures cause sometimes problems in the analysis of CTs of the temporal bone. The aim of this study was: to analyze the visibility of subtle structures and to estimate the incidence of vascular anomalies. Patients and method: We retrospectively analyzed axial scans of 223 high-resolution CTs of the temporal bone obtained as single slice or spiral CT with 1 mm slice thickness. All CTs had clinical indications. Two experienced radiologists studied CTs regarding the visibility of the fine sutures, fissures and small canals and the occurrence of vascular anomalies. Results: The following structures were seen commonly: sphenosquamosal suture (76%), arcuate artery canal (93%), vestibular aqueduct (89%), mastoid emissary vein (82%), singular canal (56%). Not so commonly were observed: tympanosquamosal suture (31%), mastoid canaliculus (28%), lateral sigmoid sinus (28%), petrotympanic fissure (24%), tympanomastoid suture (10%). Seldom we identified: the inferior tympanic canaliculus (6%), high jugular bulb (6%), anterior sigmoid sinus (5%), dehiscent internal carotid artery canal (2%), persistent petrosquamosal sinus (1%), dehiscent jugular bulb (1%). Persistent stapedial artery, aberrant internal carotid artery, dehiscent jugular bulb, high jugular bulb with diverticulum, anterior and dehiscent sigmoid sinus were detected in below 1% of the analyzed temporal bones. The frequency of asymmetry of the jugular foramen, which varied between 3% and 42%, depended on different criterions of size. Conclusion: A profound knowledge of normal anatomy and anomalies of the temporal bone avoids misinterpretation as pathological lesions and iatrogenic bleedings.

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

    Medline Plus

    Full Text Available ... its ability to image bone, soft tissue and blood vessels all at the same time. Unlike conventional x-rays, CT scanning provides very detailed images of many types of tissue as well as the lungs, bones, ...

  13. Analytic Validation of the Automated Bone Scan Index as an Imaging Biomarker to Standardize Quantitative Changes in Bone Scans of Patients with Metastatic Prostate Cancer

    Science.gov (United States)

    Anand, Aseem; Morris, Michael J.; Kaboteh, Reza; Båth, Lena; Sadik, May; Gjertsson, Peter; Lomsky, Milan; Edenbrandt, Lars; Minarik, David; Bjartell, Anders

    2016-01-01

    A reproducible and quantitative imaging biomarker is needed to standardize the evaluation of changes in bone scans of prostate cancer patients with skeletal metastasis. We performed a series of analytic validation studies to evaluate the performance of the automated bone scan index (BSI) as an imaging biomarker in patients with metastatic prostate cancer. Methods Three separate analytic studies were performed to evaluate the accuracy, precision, and reproducibility of the automated BSI. Simulation study: bone scan simulations with predefined tumor burdens were created to assess accuracy and precision. Fifty bone scans were simulated with a tumor burden ranging from low to high disease confluence (0.10–13.0 BSI). A second group of 50 scans was divided into 5 subgroups, each containing 10 simulated bone scans, corresponding to BSI values of 0.5, 1.0, 3.0, 5.0, and 10.0. Repeat bone scan study: to assess the reproducibility in a routine clinical setting, 2 repeat bone scans were obtained from metastatic prostate cancer patients after a single 600-MBq 99mTc-methylene diphosphonate injection. Follow-up bone scan study: 2 follow-up bone scans of metastatic prostate cancer patients were analyzed to determine the interobserver variability between the automated BSIs and the visual interpretations in assessing changes. The automated BSI was generated using the upgraded EXINI boneBSI software (version 2). The results were evaluated using linear regression, Pearson correlation, Cohen κ measurement, coefficient of variation, and SD. Results Linearity of the automated BSI interpretations in the range of 0.10–13.0 was confirmed, and Pearson correlation was observed at 0.995 (n = 50; 95% confidence interval, 0.99–0.99; P cancer. PMID:26315832

  14. Brain CT scan in acute carbon monoxide poisoning

    International Nuclear Information System (INIS)

    The brain CT findings in 19 patients with acute carbon monoxide poisoning was analysed and the emphasis was placed on the relationship between CT findings and prognosis. Five had a normal manifestation in CT ; eight had the findings of ovoid or patchy low density area in globus pallidus, bilateral or unlateral, during the second day to fifth week after poisoning, and the low density areas were decreasing and blurring in edge in follow up and at last disappeared during 3 - 14 weeks in three cases of them ; nine showed the appearance of diffuse low density of white matter and of globus pallidus in some of them ; two had an appearance of brain atrophy. The pathology of CT findings mentioned above may be brain edema, necrosis, malacia and degeneration in gray matter and globus pallidus. The result suggested the cases with normal CT manifestation, cerebral edema and decreasing and disappearing low density area had a good prognosis, in contrary, the cases with persistant low density in globus pallidus had a poorer prognosis. (author)

  15. Unsuspected costo-vertebral fractures demonstrated by bone scanning in the child abuse syndrome

    International Nuclear Information System (INIS)

    Many patterns of injury have been described in the child abuse syndrome. Until recently, all the bone manifestations of this syndrome have been diagnosed radiologically. Four cases of multiple costovertebral fracture diagnosed by bone scan are described and their etiology discussed. The use of bone scanning in identifying fractures which previously would have been missed is advocated. (orig.)

  16. Advantage of CT scan in muscular pathology. Personal cases and review of the literature

    Energy Technology Data Exchange (ETDEWEB)

    Laroche, M.; Rousseau, H.; Mazieres, B.; Bonafe, A.; Joffre, F.; Arlet, J.

    1989-05-01

    The advantage of CT scans in muscular pathology is studied. The scan, in addition to the diagnosis of tumors and muscular abscesses, permits to differentiate primary myopathies from neurogenic atrophies: in the course of myopathies, the muscle volume is preserved and they appear as a hypodensity; in neurogenic atrophies, the muscle volume is reduced with preserved density. The CT scan permits to determine the extension of these lesions. In the course of polymyositis, certain forms of rheumatid arthritis, the scan discloses a trabecular and 'worm-eaten' aspect of the muscles. This is also observed after long-term steroid therapy and other endocrine diseases (hyperthyroidism, osteomalacia) indicating an infra-clinical myopathy. In vertebral osteoporosis with fractures and patients with chronic lumbalgia, very ofter, an atrophy of the spinal muscle is observed. Finally, in the course of acquired kyphosis of the adult patient (camptocormia), the CT scan suggest an isolated myopathy, with late manifestations, of the paravertebral muscles.

  17. Dual energy CT with one full scan and a second sparse-view scan using structure preserving iterative reconstruction (SPIR)

    Science.gov (United States)

    Wang, Tonghe; Zhu, Lei

    2016-09-01

    Conventional dual-energy CT (DECT) reconstruction requires two full-size projection datasets with two different energy spectra. In this study, we propose an iterative algorithm to enable a new data acquisition scheme which requires one full scan and a second sparse-view scan for potential reduction in imaging dose and engineering cost of DECT. A bilateral filter is calculated as a similarity matrix from the first full-scan CT image to quantify the similarity between any two pixels, which is assumed unchanged on a second CT image since DECT scans are performed on the same object. The second CT image from reduced projections is reconstructed by an iterative algorithm which updates the image by minimizing the total variation of the difference between the image and its filtered image by the similarity matrix under data fidelity constraint. As the redundant structural information of the two CT images is contained in the similarity matrix for CT reconstruction, we refer to the algorithm as structure preserving iterative reconstruction (SPIR). The proposed method is evaluated on both digital and physical phantoms, and is compared with the filtered-backprojection (FBP) method, the conventional total-variation-regularization-based algorithm (TVR) and prior-image-constrained-compressed-sensing (PICCS). SPIR with a second 10-view scan reduces the image noise STD by a factor of one order of magnitude with same spatial resolution as full-view FBP image. SPIR substantially improves over TVR on the reconstruction accuracy of a 10-view scan by decreasing the reconstruction error from 6.18% to 1.33%, and outperforms TVR at 50 and 20-view scans on spatial resolution with a higher frequency at the modulation transfer function value of 10% by an average factor of 4. Compared with the 20-view scan PICCS result, the SPIR image has 7 times lower noise STD with similar spatial resolution. The electron density map obtained from the SPIR-based DECT images with a second 10-view scan has an

  18. Malignancy rate of biopsied suspicious bone lesions identified on FDG PET/CT

    Energy Technology Data Exchange (ETDEWEB)

    Adams, Hugo J.A.; Kwee, Thomas C. [University Medical Center Utrecht, Department of Radiology and Nuclear Medicine, Utrecht (Netherlands); Klerk, John M.H. de [Meander Medical Center, Department of Nuclear Medicine, Amersfoort (Netherlands); Heggelman, Ben G.F. [Meander Medical Center, Department of Radiology, Amersfoort (Netherlands); Dubois, Stefan V. [Meander Medical Center, Department of Pathology, Amersfoort (Netherlands)

    2016-07-15

    To determine the malignancy rate of bone lesions identified on FDG PET/CT in patients who have undergone CT-guided biopsy because of the suspicion of malignancy. This single-centre retrospective study spanned eight consecutive years and included all patients who underwent both FDG PET/CT and CT-guided bone biopsy because of the suspicion of malignancy. The positive predictive value (PPV) for malignancy was calculated, and different patient and imaging characteristics were compared between malignant and benign bone lesions. Of 102 included patients with bone lesions that all showed FDG uptake exceeding mediastinal uptake, bone biopsy showed a malignant lesion in 91 patients, yielding a PPV for malignancy of 89.2 % (95 % CI 81.7 - 93.9 %). In the 94 patients with bone lesions that showed FDG uptake exceeding liver uptake, bone biopsy showed a malignant lesion in 83 patients, yielding a PPV for malignancy of 88.3 % (95 % CI 80.1 - 93.5 %). Higher age, bone marrow replacement of the lesion seen on CT, expansion of the lesion seen on CT, and presence of multifocal lesions on FDG PET/CT were significantly more frequent in patients with malignant lesions than in those with benign bone lesions (P = 0.044, P = 0.009, P = 0.015, and P = 0.019, respectively). Furthermore, there was a trend towards a higher incidence of cortical destruction (P = 0.056) and surrounding soft tissue mass (P = 0.063) in patients with malignant bone lesions. The PPV for malignancy of suspicious bone lesions identified on FDG PET/CT is not sufficiently high to justify changes in patient management without histopathological confirmation. Nevertheless, ancillary patient and imaging characteristics may increase the likelihood of a malignant bone lesion. (orig.)

  19. Orthogonal views improves localisation in bone scans of wrist

    Energy Technology Data Exchange (ETDEWEB)

    Roth, A.L.

    1997-09-01

    Full text: Of all nuclear medicine studies, bone scans are the most fundamental. However, straightforward these may seem, there are always mechanisms that can be implemented which assist in a more precise diagnosis, particularly in areas with an intricate bone structure. An 18-year-old right-handed student presented to her doctor with a one month history of pain over the right distal radio-ulna joint area. Clinically, she had prominence of the right ulna, which suggested that there may have been a previous injury to the wrist. Also, pronation/supination were painful where there was swelling of the extensor carpi ulnaris tendon, as well as some discomfort with clicking in ulna deviation/rotation. The X-rays demonstrated some premature radial epiphysial closure. A bone scan was requested to attempt to localise the main inflammatory focus. The dynamic study was performed in the planar projection with an immediate blood pool for 300k being taken. These demonstrated a vascular blush medially. A medial blood pool image was acquired and it localised the abnormal vascularity as being dorsal. A separate focal area of less intense blood pooling was also noted in the line of the distal ulna. Delayed images showed increased uptake localised to the ulna styloid. Anatomically, the superficial vascular blush correlated with tenosynovitis. Hence, the orthogonal initial and delayed images were definitive in the diagnoses of tenosynovitis of the extensor carpi ulnaris tendon. This clearly complements the information provided by the palmar view. However, it is important to remember that an increased radiation dose to the technologist is incurred as a result of the extra orthogonal view, hence attention to technique is imperative.

  20. 3D Reconstruction in Spiral Multislice CT Scans

    Directory of Open Access Journals (Sweden)

    M. Ghafouri

    2005-08-01

    Full Text Available Introduction & Background: The rapid development of spiral (helical computed tomography (CT has resulted in exciting new applications for CT. One of these applications, three-dimensional (3D CT with volume ren-dering, is now a major area of clinical and academic interest. One of the greatest advantages of spiral CT with 3D volume rendering is that it provides all the necessary information in a single radiologic study (and there-fore at the lowest possible price in cases that previously required two or more studies. Three-dimensional vol-ume rendering generates clinically accurate and immediately available images from the full CT data set with-out extensive editing. It allows the radiologist and clinician to address specific questions concerning patient care by interactively exploring different aspects of the data set. Three-dimensional images integrate a series of axial CT sections into a form that is often easier to interpret than the sections themselves and can be made to appear similar to other more familiar images such as catheter angiograms. The data are organized into a 3D matrix of volume elements (voxels. The screen of the computer monitor is a 2D-surface composed of discrete picture elements (pixels. Presenting what is stored in memory (ie, floating within the monitor on a 2D-screen is a challenge, but it is the very problem that 3D reconstruc-tion software has creatively solved. Voxel selection is usually accomplished by projecting lines (rays through the data set that correspond to the pixel matrix of the desired 2D image. Differences in the images produced with various 3D rendering techniques are the result of variations in how voxels are selected and weighted. In this article, I compare 3D volume rendering of spiral CT data with other rendering techniques (shaded surface display, maximum intensity projection and present a brief history of 3D volume rendering and discuss the im-plementation of this promising technology in terms of

  1. Temporal bone trauma and the role of multidetector CT in the emergency department.

    Science.gov (United States)

    Zayas, Julio O; Feliciano, Yara Z; Hadley, Celene R; Gomez, Angel A; Vidal, Jorge A

    2011-10-01

    The temporal bone anatomy is complex, with many critical structures in close association with one another. The temporal bone region comprises cranial nerves V, VI, VII, and VIII; vascular structures such as the internal carotid and middle meningeal arteries; sigmoid sinus; jugular bulb; and sensorineural and membranous structures of the inner ear. Most temporal bone fractures are a result of high-energy blunt head trauma. Multidetector computed tomography (CT) plays a fundamental role in the initial evaluation of patients with polytrauma in the emergency department. Multidetector CT may help identify important structural injuries that may have devastating complications such as sensorineural hearing loss, conductive hearing loss, dizziness and balance dysfunction, perilymphatic fistulas, cerebrospinal fluid leaks, facial nerve paralysis, and vascular injury. Although classifying temporal bone fractures helps physicians understand and predict trauma-associated complications and guide treatment, identifying injury to critical structures is more important for guiding management and determining prognosis than is simply classifying temporal bone fractures into a general category. Many temporal bone fractures and complications may be readily identified and characterized at routine cervical, maxillofacial, and head multidetector CT performed in patients with polytrauma, without the need for dedicated temporal bone multidetector CT. Dedicated temporal bone multidetector CT should be considered when there is a high degree of suspicion for temporal bone fractures and no fractures are identified at head, cervical, or maxillofacial CT. PMID:21997992

  2. Adherence to follow-up CT scans in patients with small pulmonary nodules, a retrospective study

    DEFF Research Database (Denmark)

    Johansson, Sofie Lock; Gerner Hansen, Niels-Christian

    2010-01-01

    Adherence to follow-up CT scans in patients with small pulmonary nodules, a retrospective study The Danish National guidelines have since 2008 suggested serial follow-up CT scans at 3, 6, 12, and 24 months for nodules between 5 and 10 mm and at 12 and 24 months for nodules less than 5 mm in accor...... is that management of the follow-up of small nodules did improve in 2008-2009, but adherence to the guidelines was still limited. We will now implement a prospective program for monitoring the adherence to the follow-up CTs.......Adherence to follow-up CT scans in patients with small pulmonary nodules, a retrospective study The Danish National guidelines have since 2008 suggested serial follow-up CT scans at 3, 6, 12, and 24 months for nodules between 5 and 10 mm and at 12 and 24 months for nodules less than 5 mm...... in the four year period 2006-2009. In 72 cases, 19 in 2006-2007 and 51 in 2008-2009, one or more small nodules, with diameter ≤ 10 mm, were detected on CT in patients with no known recent malignant disease. For these patients follow-up was suggested, either with CT or PET-CT. One of the 70 patients from 2008...

  3. Potential cancer risk associated to CT scan. State of the art of epidemiological studies

    Energy Technology Data Exchange (ETDEWEB)

    Bernier, Marie-Odile; Baysson, Neige Joumy Helene; Jacob, Sophie; Laurier, Dominique [Institute for Radiological Protection and Nuclear Safety (IRSN), Fontenay-aux-Roses (France). Lab. of Epidemiology

    2013-07-01

    Introduction: The increasing use of computed tomography (CT) scans in paediatric population raises the question of a possible health impact of ionizing radiation exposure associated with CT scans. Material and methods: Two large cohort studies have been recently published that assessed the risk of cancer related to CT examinations of children and young adults. Methodology and results of these studies are presented. Results: The UK cohort included over 176,000 young people, who underwent one or more CT scans between 1985 and 2002. The Australian study compared the risk of cancer and leukaemia in a population of 680,000 young people exposed to CT scans between 1985 and 2005 to non-exposed similar age people. Both studies showed a significant dose-response relation between exposure to CT and leukaemia or brain tumour risks. These results are consistent with predictions from A-bomb survivors' data. However, uncertainties in dosimetric estimation and potential bias linked to underlying medical conditions should be considered. Conclusion and perspectives: Further studies with more accurate dosimetry and assessment of potential bias and uncertainties are needed. Ongoing national studies and the European collaborative EPI-CT study will help to better understand the relation between low level radiation exposure and cancer and to support recommendations for patients'' radiation protection. (orig.)

  4. Potential cancer risk associated to CT scan. State of the art of epidemiological studies

    International Nuclear Information System (INIS)

    Introduction: The increasing use of computed tomography (CT) scans in paediatric population raises the question of a possible health impact of ionizing radiation exposure associated with CT scans. Material and methods: Two large cohort studies have been recently published that assessed the risk of cancer related to CT examinations of children and young adults. Methodology and results of these studies are presented. Results: The UK cohort included over 176,000 young people, who underwent one or more CT scans between 1985 and 2002. The Australian study compared the risk of cancer and leukaemia in a population of 680,000 young people exposed to CT scans between 1985 and 2005 to non-exposed similar age people. Both studies showed a significant dose-response relation between exposure to CT and leukaemia or brain tumour risks. These results are consistent with predictions from A-bomb survivors' data. However, uncertainties in dosimetric estimation and potential bias linked to underlying medical conditions should be considered. Conclusion and perspectives: Further studies with more accurate dosimetry and assessment of potential bias and uncertainties are needed. Ongoing national studies and the European collaborative EPI-CT study will help to better understand the relation between low level radiation exposure and cancer and to support recommendations for patients'' radiation protection. (orig.)

  5. Paediatric dosimetry of 18F-FDG whole body PET/CT scans

    International Nuclear Information System (INIS)

    A combined 18F-FDG (18F-2-deoxy-D-glucose) positron emission tomography/computed tomography (PET/CT) scan provides both the metabolic information from FDG-PET and anatomic information from CT in a single examination. The use of PET/CT for management of malignancies in children has increased over the past few years. This raises an important consideration of radiation exposure in children since they are relatively more radiosensitive than adults and also have a potential for a longer life thereby increasing the probability of manifestation of late radiation effects; particularly cancer. Unfortunately, the data regarding the doses received by children from undergoing such examinations is scarce. The present study aims at estimating the effective doses to paediatric patients from whole body 18F-FDG PET/CT studies. The purpose of the study is to estimate the radiation doses to children from undergoing whole body PET/CT scans using 18F-FDG

  6. Evaluation of Helical CT Scanning in Judging the Invasion and Metastasis of Gastric Carcinoma

    Institute of Scientific and Technical Information of China (English)

    GAOJianbo; KONGXiangquan; GUOHua; LIShuxin; YANGXuehua; LIYintai; ZHANGZhixu

    2004-01-01

    To determine the accuracy of triphase enhanced helical CT in judging the invasion and metastasis of gastric carcinoma, and to discuss the relation between imaging signs and pathological findings. Methods: Triphase enhanced helical CT scanning was performed in 46 patients with gastric carcinoma. Imaging findings were compared with postoperative pathologic results. Results: (1) The accuracy of helical CT for diagnosing involvement of tunica serosa, lymph node metastasis and distant metastasis was 84.8%, 87.0% and 100~ respectively. (2) CT signs of serosal involvement, lymph node metastasis and distant metastasis were in good accordance with pathological findings (P<0.05). Conclusion: Triphase enhanced helical CT scans can comprehensively and precisely reflect the pathologic characteristics of gastric carcinoma, thus it is a reliable technique for the diagnosis of this disease.

  7. SU-E-J-250: A Methodology for Active Bone Marrow Protection for Cervical Cancer Intensity-Modulated Radiotherapy Using 18F-FLT PET/CT Image

    International Nuclear Information System (INIS)

    Purpose: The purpose of this study was to compare a radiation therapy treatment planning that would spare active bone marrow and whole pelvic bone marrow using 18F FLT PET/CT image. Methods: We have developed an IMRT planning methodology to incorporate functional PET imaging using 18F FLT/CT scans. Plans were generated for two cervical cancer patients, where pelvicactive bone marrow region was incorporated as avoidance regions based on the range: SUV>2., another region was whole pelvic bone marrow. Dose objectives were set to reduce the volume of active bone marrow and whole bone marraw. The volumes of received 10 (V10) and 20 (V20) Gy for active bone marrow were evaluated. Results: Active bone marrow regions identified by 18F FLT with an SUV>2 represented an average of 48.0% of the total osseous pelvis for the two cases studied. Improved dose volume histograms for identified bone marrow SUV volumes and decreases in V10(average 18%), and V20(average 14%) were achieved without clinically significant changes to PTV or OAR doses. Conclusion: Incorporation of 18F FLT/CT PET in IMRT planning provides a methodology to reduce radiation dose to active bone marrow without compromising PTV or OAR dose objectives in cervical cancer

  8. Effect of bromocriptine on PRL-secreting pituitary adenomas. Analysis by CT scan

    Energy Technology Data Exchange (ETDEWEB)

    Niwa, Jun; Sato, Osamu; Daibo, Masahiko; Inoue, Yoshitoshi; Tanabe, Sumiyoshi (Sapporo Medical Coll. (Japan))

    1982-06-01

    The effect of bromocriptine on the CT scan was examined in eight patients with prolactinsecreting pituitary adenomas. All the patients showed a high serum PRL level (> 30 ng/ml) after surgical treatment. Bromocriptine was administered at the rate of from 7.5 to 25 mg per day. The effects on the CT scan and metrizamide CT cisternography were then evaluated. The data suggest: (1) The effect of bromocriptine on the CT scan was shown in the reduction of enhanced area or the decrease in the enhanced density, and it was classified into three types: Type I showed a reduction of the enhanced area, Type II showed a decrease in the enhanced density, and Type III showed no change on the CT sacn. When the shrinkage of the adenoma was examined by means of metrizamide CT cisternography, Type I showed an actual shrinkage of the adenoma, but Type II showed only a pseudoshrinkage of the adenoma. Thus, the shrinkage of the adenoma should be determined by metrizamide CT cisternography. (2) The normalization of the serum PRL level was related to the effect on the CT scan, but it occurred before the effect on the CT scan. Therefore, the normalization of the serum PRL level can not be used to distinguish between Type I and Type II. (3) An initial shrinkage of the adenoma occurred within one or two months, and there was a notable shrinkage by nine months after treatment. A change from an enhanced high density to isodensity occurred by one month and to a low density by seven months after treatment, therefore, a reduction in the enhanced density occurred earlier than a decrease in the enhanced area.

  9. Head CT scan in Iranian minor head injury patients: evaluating current decision rules.

    Science.gov (United States)

    Sadegh, Robab; Karimialavijeh, Ehsan; Shirani, Farzaneh; Payandemehr, Pooya; Bahramimotlagh, Hooman; Ramezani, Mahtab

    2016-02-01

    The objective of this study is to select one of the seven available clinical decision rules for minor head injury, for managing Iranian patients. This was a prospective cohort study evaluating medium- or high-risk minor head injury patients presenting to the Emergency Department. Patients with minor head trauma who were eligible for brain imaging based on seven available clinical decision rules (National Institute for Health and Clinical Excellence (NICE), National Emergency X-Radiography Utilization Study (NEXUS)-II, Neurotraumatology Committee of the World Federation of Neurosurgical Societies (NCWFNS), New Orleans, American College of Emergency Physicians (ACEP) Guideline, Scandinavian, and Canadian computed tomography (CT) head rule) were selected. Subjects were underwent a non-contrast axial spiral head CT scan. The outcome was defined as abnormal and normal head CT scan. Univariate analysis and stepwise linear regression were applied to show the best combination of risk factors for detecting CT scan abnormalities. Five hundred patients with minor head trauma were underwent brain CT scan. The following criteria were derived by stepwise linear regression: Glasgow Coma Scale (GCS) less than 15, confusion, signs of basal skull fracture, drug history of warfarin, vomiting more than once, loss of consciousness, focal neurologic deficit, and age over 65 years. This model has 86.15 % (75.33-93.45 %) sensitivity and 46.44 % (46.67-51.25 %) specificity in detecting minor head injury patients with CT scan abnormalities (95 % confidence interval). Of seven decision rules, only the Canadian CT Head Rule possesses seven of the eight high-risk factors associated with abnormal head CT results which were identified by this study. This study underlines the Canadian CT Head Rule's utility in Iranian minor head injury patients. Our study encourages researchers to evaluate available guidelines in different communities. PMID:26407978

  10. The evolution of a brain abscess the complementary roles of radionuclide (RN) and computed tomography (CT) scans

    International Nuclear Information System (INIS)

    Serial /sup 99m/Tc glucoheptonate brain scans demonstrated a brain abscess in a patient from the earliest phase of acute focal encephalitis (cerebritis) through the capsule formation and the recovery phase. The role of the RN and CT scans in the diagnosis of the early stage of cerebritis and the complementary nature of RN and CT scans in intracranial infections, particularly abscesses, are discussed. Guidelines for the use of RN and CT scans are suggested

  11. The evolution of a brain abscess the complementary roles of radionuclide (RN) and computed tomography (CT) scans

    Energy Technology Data Exchange (ETDEWEB)

    Masucci, E.F.; Sauerbrunn, B.J.

    1982-04-01

    Serial /sup 99m/Tc glucoheptonate brain scans demonstrated a brain abscess in a patient from the earliest phase of acute focal encephalitis (cerebritis) through the capsule formation and the recovery phase. The role of the RN and CT scans in the diagnosis of the early stage of cerebritis and the complementary nature of RN and CT scans in intracranial infections, particularly abscesses, are discussed. Guidelines for the use of RN and CT scans are suggested.

  12. A study of bone uptake according to renal function in the whole body bone scan

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Yong In; Jang, Dong Gun [Dept. of Nuclear Medicine, Dongnam Institute of Radiological and Medical Sciences Cancer Center, Busan (Korea, Republic of); Park, Cheol Woo [Dept. of Radiological Technology Dong-Eui Institute of Technology, Busan (Korea, Republic of)

    2013-12-15

    Whole body bone scan has been used to confirm bone metastasis and follow-up study with radio isotope. However, if the factors related to 99mTc uptake and waiting time for study are inappropriate, it would be image of low quality. The purpose of present study was to investigate correlation between the evaluation index of renal function and uptake of radiopharmaceuticals. The population for this retrospective study consisted of 387 patients who underwent whole body bone scan between June 2012 and December 2012. As a result of quantitative and qualitative analysis, we were able to confirm that GFR of less than normal range and creatinine levels in blood of more than average are more likely to be under the mean uptake rate. As a result of analysis on the indicator affecting soft-tissue and bone uptake, the correlation of all elements was somewhat low. Also there are no statistically significances due to the other parameters we did not deal with. Therefore, further research on additional factors is needed for exact study and improvement of the image quality.

  13. CT scans in young people in Northern England: trends and patterns 1993-2002

    International Nuclear Information System (INIS)

    Although CT can be greatly beneficial, its relatively high radiation doses have caused public health concerns. To assess patterns in CT usage among patients aged less than 22 years in Northern England during the period 1993-2002. Electronic data were obtained from radiology information systems of all nine National Health Service trusts in the region. A total of 38,681 scans had been performed in 20,483 patients aged less than 22 years. The number of CT examinations rose, with the steepest increase between 1997 and 2000. The number of patients scanned per year increased less dramatically, with 2.24/1,000 population aged less than 22 years having one scan or more in 1993 compared to 3.54/1,000 in 2002. This reflects an increase in the median number of scans per patient, which rose from 1 in 1993 to 2 by 1999. More than 70% of CT examinations were of the head, with the number of head examinations varying with time and patient age. The frequency of CT scans in this population more than doubled during the study period. This is partly, but not wholly, explained by an increase in the number of scans per patient. (orig.)

  14. Computed Tomography (CT) -- Head

    Medline Plus

    Full Text Available ... image recording plate. Bones appear white on the x-ray; soft tissue, such as organs like the heart or ... of CT is its ability to image bone, soft tissue and blood vessels all at the same time. Unlike conventional x-rays, CT scanning provides very detailed images of many ...

  15. Computed Tomography (CT) -- Sinuses

    Medline Plus

    Full Text Available ... image recording plate. Bones appear white on the x-ray; soft tissue, such as organs like the heart or ... of CT is its ability to image bone, soft tissue and blood vessels all at the same time. Unlike conventional x-rays, CT scanning provides very detailed images of many ...

  16. The role of bone centers in the pathogenesis of craniosynostosis: An embryologic approach using CT measurements in isolated craniosynostosis and Apert and Crouzon syndromes

    NARCIS (Netherlands)

    I.M.J. Mathijssen (Irene); J.M. Vaandrager (Michiel); J.C.H.M. van der Meulen (Jacques); H. Pieterman; F.W. Zonneveld; S. Kreiborg; C. Vermeij-Keers (Christl)

    1996-01-01

    textabstractThis paper describes the role of the displacement of bone centers, i.e., the tubers, in the pathogenesis of craniosynostosis. This displacement was studied in 54 patients with isolated or syndromic craniosynostosis in the form of CT scans as well as in two dry neonate s

  17. A multicenter, randomized controlled trial of immediate total-body CT scanning in trauma patients (REACT-2).

    NARCIS (Netherlands)

    Sierink, J.C.; Saltzherr, T.P.; Beenen, L.F.; Luitse, J.S.; Hollmann, M.W.; Reitsma, J.B.; Edwards, M.J.R.; Hohmann, J.; Beuker, B.J.; Patka, P.; Suliburk, J.W.; Dijkgraaf, M.G.; Goslings, J.C.

    2012-01-01

    BACKGROUND: Computed tomography (CT) scanning has become essential in the early diagnostic phase of trauma care because of its high diagnostic accuracy. The introduction of multi-slice CT scanners and infrastructural improvements made total-body CT scanning technically feasible and its usage is curr

  18. A multicenter, randomized controlled trial of immediate total-body CT scanning in trauma patients (REACT-2)

    NARCIS (Netherlands)

    J.C. Sierink (Joanne); T.P. Saltzherr (Teun); L.F.M. Beenen (Ludo); J.S.K. Luitse; M.W. Hollmann (Markus); J.B. Reitsma (Johannes); M.J.R. Edwards (Michael); J. Hohmann (Joachim); B.J.A. Beuker (Benn); P. Patka (Peter); J.W. Suliburk (James); M.G.W. Dijkgraaf (Marcel); J.C. Goslings (Carel)

    2012-01-01

    textabstractBackground: Computed tomography (CT) scanning has become essential in the early diagnostic phase of trauma care because of its high diagnostic accuracy. The introduction of multi-slice CT scanners and infrastructural improvements made total-body CT scanning technically feasible and its u

  19. Quality assurance of CT scanning for industrial applications

    DEFF Research Database (Denmark)

    Angel, Jais Andreas Breusch

    assurance of CT for industrial measurements both in the manufacturing and in the meat processing industries. Various methods and reference objects have been developed in this project to establish metrological traceability of measurements. Moreover investigations as well as international comparisons...... in the field of application on the two different areas have been carried out. Different reference objects have been developed and introduced for the manufacturing industry: step gauge, step cylinder and a cylindrical multi-material assembly. These objects can be used for correction of measurement errors...... in the CT model. Moreover, two reference objects are calibrated objects from the manufacturing industry: a threaded tube from the medical industry and a LEGO brick from the toy industry. Establishment of traceability for all objects is performed using coordinate measuring machines (CMMs) with known...

  20. CT of multiple sclerosis: reassessment of delayed scanning with high doses of contrast material

    International Nuclear Information System (INIS)

    A prospective study involving 87 patients was carried out to evaluate the necessity for a high dose of contrast material in addition to delayed computed tomographic (CT) scanning for optimal detection of the lesions of multiple sclerosis in the brain. In patients with either clinically definite multiple sclerosis or laboratory-supported definite multiple sclerosis, CT scans were obtained with a uniform protocol. Lesions consistent with multiple sclerosis were demonstrated on the second scan in 54 patients. In 36 of these 54 patients, the high-dose delayed scan added information. These results are quite similar to those of a previous study from this institution using different patients, in whom the second scan was obtained immediately after the bolus injection of contrast material containing 40 g of organically bound iodine. The lack of real difference in the results of the two studies indicate that the increased dose, not just the delay in scanning, is necessary for a proper study

  1. Which metabolic imaging, besides bone scan with 99mTc-phosphonates, for detecting and evaluating bone metastases in prostatic cancer patients? An open discussion.

    Science.gov (United States)

    Bombardieri, E; Setti, L; Kirienko, M; Antunovic, L; Guglielmo, P; Ciocia, G

    2015-12-01

    Prostate cancer bone metastases occur frequently in advanced cancer and this is matter of particular attention, due to the great impact on patient's management and considering that a lot of new emerging therapeutic options have been recently introduced. Imaging bone metastases is essential to localize lesions, to establish their size and number, to study characteristics and changes during therapy. Besides radiological imaging, nuclear medicine modalities can image their features and offer additional information about their metabolic behaviour. They can be classified according to physical characteristics, type of detection, mechanism of uptake, availability for daily use. The physiopathology of metastases formation and the mechanisms of tracer uptake are essential to understand the interpretation of nuclear medicine images. Therefore, radiopharmaceuticals for bone metastases can be classified in agents targeting bone (99mTc-phosphonates, 18F-fluoride) and those targeting prostatic cancer cells (18F-fluoromethylcholine, 11C-choline, 18F-fluorodeoxyglucose). The modalities using the first group of tracers are planar bone scan, SPECT or SPECT/CT with 99mTc-diphosphonates, and 18F-fluoride PET/CT, while the modalities using the second group include 18F/11C-choline derivatives PET/CT, 18F-FDG PET/CT and PET/CT scans with several other radiopharmaceuticals described in the literature, such as 18F/11C-acetate derivatives, 18F-fluoro-5α-dihydrotestosterone (FDHT), 18F-anti-1-amino-3-fluorocyclobutane-1-carboxylic acid (FACBC), 18F-2'-fluoro-5-methyl-1-β-D-arabinofuranosyluracil (FMAU) and 68Ga-labeled-prostate specific membrane antigen (PMSA) PET/TC. However, since data on clinical validation for these last novel modalities are not conclusive and/or are not still sufficient in number, at present they can be still considered as promising tools under evaluation. The present paper considers the nuclear modalities today available for the clinical routine. This overview wants

  2. Application of offset-CT scanning to the inspection of high power feeder lines and connections

    Science.gov (United States)

    Schneberk, Daniel; Maziuk, Robert; Soyfer, Boris; Shashishekhar, N.; Alreja, Rahul

    2016-02-01

    VJT is developing techniques and scanning methods for the in-situ Radiographic and Computed Tomographic inspection of underground high-power feeder cables. The goals for the inspection are to measure the 3D state of the cables and the cable-connections. Recent in-situ Digital Radiographic inspections performed by VJT have demonstrated the value of NDE inspection information for buried power lines. These NDE data have raised further questions as to the exact state of the cables and connections and pointed to the need for more 3D information of the type provided by volumetric CT scanning. VJT is pursuing a three phased approach to address the many issues involved in this type of inspection: 1) develop a high-power feeder-cable test-bed CT scanner, 2) acquire scans on underground feeder pipes that have been removed from service, and 3) from the work in 1) and 2) develop limited-angle CT scanning methods for extending in-situ Digital Radiography to volumetric CT measurements. To this end, VJT has developed and fielded a high-energy test-bed Gantry-type CT scanner (the source and detector move around the object) with a number of important properties. First, the geometry of the gantry-scans can be configured to match the techniques used in the in-situ radiographic inspection. The same X-ray source is employed as in portable Radiographic inspections, a 7.5 MeV Betatron coupled to a Perkin-Elmer Amorphous Silicon detector. Offset-CT scanning is employed as the high-power feeder line assembly is larger than the detector. A description of this scanner and the scan geometry will be presented showing the connection to in-situ radiography. Results from the CT scans of high-power feeder-cable specimens removed from service will be presented with a focus on the inspection potential of volumetric CT data on these assemblies. An evaluation of the scan performance properties of these data compared to the spectrum of life-cycle inspection issues will be presented. Continuing and

  3. An Inflammatory Dentigerous Cyst Shows Rim Uptake on Bone Scan: A Case Report

    Energy Technology Data Exchange (ETDEWEB)

    Son, Hye Joo; Jeong, Young Jin; Jeong, Jin Sook; Kang, Doyoung [Dong-A Univ. Medical Center, Busan (Korea, Republic of)

    2014-03-15

    Dentigerous cysts are developmental odontogenic jaw cysts, commonly manifesting in the 2nd and 3rd decades of life. This article presents an extremely rare case of dentigerous cyst showing increased uptake in the peripheral rim on bone scan. Herein, we discuss the clinical, radiographic, and histologic features of dentigerous cysts as well as the pathological mechanism underlying their activities on the bone scan. Bone scan was a sensitive tool for detecting the biologic activity of dentigerous cyst in our case.

  4. CT scans of the hypopharynx and larynx during inspiration, expiration, breath holding and phonation

    International Nuclear Information System (INIS)

    CT scans of the hypopharynx and larynx during inspiration, expiration, breath holding and phonation of the letter E were performed on seven volunteers. Two mm contiguous scans were obtained to span the glottis and supraglottic area. The vocal cords were shown in the paramedian or median position on breath holding and phonation. The ditails of the arytenoid cartilages were better visualized with thin slices. The laryngeal ventricles were demonstrable on phonation scans. (author)

  5. Scanning electron microscopy of human cortical bone failure surfaces.

    Science.gov (United States)

    Braidotti, P; Branca, F P; Stagni, L

    1997-02-01

    Undecalcified samples extracted from human femoral shafts are fractured by bending and the fracture surfaces are examined with a scanning electron microscope (SEM). The investigation is performed on both dry and wet (hydrated with a saline solution) specimens. SEM micrographs show patterns in many respects similar to those observed in fractography studies of laminated fiber-reinforced synthetic composites. In particular, dry and wet samples behave like brittle and ductile matrix laminates, respectively. An analysis carried out on the basis of the mechanisms that dominate the fracture process of laminates shows that a reasonable cortical bone model is that of a laminated composite material whose matrix is composed of extracellular noncollagenous calcified proteins, and the reinforcement is constituted by the calcified collagen fiber system. PMID:9001936

  6. Sex determination from scapular length measurements by CT scans images in a Caucasian population.

    Science.gov (United States)

    Giurazza, F; Schena, E; Del Vescovo, R; Cazzato, R L; Mortato, L; Saccomandi, P; Paternostro, F; Onofri, L; Zobel, B Beomonte

    2013-01-01

    Together with race, stature and age, sex is a main component of the biological identity. Thanks to its proportional correlation with parts of the human body, sex can be evaluated form the skeleton. The most accurate approach to determine sex by bone size is based on os coxae or skull. After natural disaster their presence can never be guaranteed, therefore the development of methods of sex determination using other skeletal elements can result crucial. Herein, sexual dimorphism in the human scapula is used to develop a two-variable discriminant function for sex estimation. We have enrolled 100 males and 100 females who underwent thoracic CT scan evaluation and we have estimated two scapular diameters. The estimation has been carried out by analyzing images of the scapulae of each patient after three dimensional post-processing reconstructions. The two-variable function allows to obtain an overall accuracy of 88% on the calibration sample. Furthermore, we have employed the mentioned function on a collection of 10 individual test sample from the collection of the "Museo di Anatomia Umana di Firenze" of the Università degli Studi di Firenze; sex has been correctly predicted on 9 skeletons.

  7. Integration of 3D anatomical data obtained by CT imaging and 3D optical scanning for computer aided implant surgery

    Directory of Open Access Journals (Sweden)

    Paoli Alessandro

    2011-02-01

    Full Text Available Abstract Background A precise placement of dental implants is a crucial step to optimize both prosthetic aspects and functional constraints. In this context, the use of virtual guiding systems has been recognized as a fundamental tool to control the ideal implant position. In particular, complex periodontal surgeries can be performed using preoperative planning based on CT data. The critical point of the procedure relies on the lack of accuracy in transferring CT planning information to surgical field through custom-made stereo-lithographic surgical guides. Methods In this work, a novel methodology is proposed for monitoring loss of accuracy in transferring CT dental information into periodontal surgical field. The methodology is based on integrating 3D data of anatomical (impression and cast and preoperative (radiographic template models, obtained by both CT and optical scanning processes. Results A clinical case, relative to a fully edentulous jaw patient, has been used as test case to assess the accuracy of the various steps concurring in manufacturing surgical guides. In particular, a surgical guide has been designed to place implants in the bone structure of the patient. The analysis of the results has allowed the clinician to monitor all the errors, which have been occurring step by step manufacturing the physical templates. Conclusions The use of an optical scanner, which has a higher resolution and accuracy than CT scanning, has demonstrated to be a valid support to control the precision of the various physical models adopted and to point out possible error sources. A case study regarding a fully edentulous patient has confirmed the feasibility of the proposed methodology.

  8. Investigation of ultra low-dose scans in the context of quantum-counting clinical CT

    Science.gov (United States)

    Weidinger, T.; Buzug, T. M.; Flohr, T.; Fung, G. S. K.; Kappler, S.; Stierstorfer, K.; Tsui, B. M. W.

    2012-03-01

    In clinical computed tomography (CT), images from patient examinations taken with conventional scanners exhibit noise characteristics governed by electronics noise, when scanning strongly attenuating obese patients or with an ultra-low X-ray dose. Unlike CT systems based on energy integrating detectors, a system with a quantum counting detector does not suffer from this drawback. Instead, the noise from the electronics mainly affects the spectral resolution of these detectors. Therefore, it does not contribute to the image noise in spectrally non-resolved CT images. This promises improved image quality due to image noise reduction in scans obtained from clinical CT examinations with lowest X-ray tube currents or obese patients. To quantify the benefits of quantum counting detectors in clinical CT we have carried out an extensive simulation study of the complete scanning and reconstruction process for both kinds of detectors. The simulation chain encompasses modeling of the X-ray source, beam attenuation in the patient, and calculation of the detector response. Moreover, in each case the subsequent image preprocessing and reconstruction is modeled as well. The simulation-based, theoretical evaluation is validated by experiments with a novel prototype quantum counting system and a Siemens Definition Flash scanner with a conventional energy integrating CT detector. We demonstrate and quantify the improvement from image noise reduction achievable with quantum counting techniques in CT examinations with ultra-low X-ray dose and strong attenuation.

  9. Trends in CT scan rates in children and pregnant women: teaching, private, public and nonprofit facilities

    Energy Technology Data Exchange (ETDEWEB)

    Hoshiko, Sumi; Smith, Daniel; Fan, Cathyn; Jones, Carrie R.; McNeel, Sandra V. [Environmental Health Investigations Branch, California Department of Public Health, Richmond, CA (United States); Cohen, Ronald A. [Children' s Hospital and Research Center Oakland, Department of Radiology, Oakland, CA (United States)

    2014-05-15

    Radiation exposure from medical sources now equals or exceeds that from natural background sources, largely attributable to a 20-fold increase in CT use since 1980. Increasing exposure to children and fetuses is of most concern due to their heightened susceptibility. More recently, CT use may be leveling or decreasing, but it is unclear whether this change is widespread or varies by type of institution. We sought to characterize trends in CT utilization in California hospitals and emergency departments among children and pregnant women, looking at different types of facilities, such as teaching, private, public and nonprofit institutions. We examined frequency of CT examinations by year from 229 facilities reporting CT usage in routinely collected California statewide data for 2005-2012. We modeled trends overall and by facility type. CT scans for pediatric and pregnant patient visits in the emergency department increased initially, then started to decline after 2008. Among hospital admissions, rates declined or leveled after 2005. In the emergency department, CT rates varied between types of facilities, with teaching hospitals reducing use sooner and more sharply than other types of facilities. CT utilization in California among children and pregnant women has begun to level or decline. Still, population exposure remains at historically high levels, warranting consideration of potential public health implications. Further examination of reasons for trends among hospital types, particularly how teaching hospitals have reduced rates of CT utilization, may help identify strategies for CT reduction without compromising patient care. (orig.)

  10. Eye lens radiation exposure and repeated head CT scans: A problem to keep in mind

    International Nuclear Information System (INIS)

    Objectives: The deterministic character of radiation-induced cataract is being called into question, raising the possibility of a risk in patients, especially children, exposed to ionizing radiation in case of repeated head CT-scans. This study aims to estimate the eye lens doses of a pediatric population exposed to repeated head CTs and to assess the feasibility of an epidemiological study. Methods: Children treated for a cholesteatoma, who had had at least one CT-scan of the middle ear before their tenth birthday, were included. Radiation exposure has been assessed from medical records and telephone interviews. Results: Out of the 39 subjects contacted, 32 accepted to participate. A total of 76 CT-scans were retrieved from medical records. At the time of the interview (mean age: 16 years), the mean number of CT per child was 3. Cumulative mean effective and eye lens doses were 1.7 mSv and 168 mGy, respectively. Conclusion: A relatively high lens radiation dose was observed in children exposed to repeated CT-scans. Due to that exposure and despite the difficulties met when trying to reach patients’ families, a large scale epidemiological study should be performed in order to assess the risk of radiation-induced cataracts associated with repeated head CT.

  11. Impact of low-dose CT scan in dual timepoint investigations: a phantom study

    DEFF Research Database (Denmark)

    Micheelsen, M A; Jensen, Mikael

    2011-01-01

    with a CT image and also use the CT for attenuation correction. In any practical hospital setting, 1 hour is too long to occupy the scanner bed and a second CT procedure thus becomes necessary. This study tries to validate to what extent the dose/quality of the second CT scan can be lowered, without...... compromising attenuation correction, lesion detection and quantification. Using a standard NEMA phantom with the GE Discovery PET/CT scanner, taken in and out between scan sessions, we have tried to find the minimal CT dose necessary for the second scan while still reaching tissue activity quantification...... within predetermined error limits. For a hot sphere to background activity concentration ratio of 1:5, the average uptake (normalised by the time corrected input activity concentration) in a sphere of 6 cm3 was found to be 0.90 ± 0.08 for the standard scan, yielding a dose of 5.5 mGy, and 0.90 ± 0...

  12. Changes in CT scan following acute embolectomy of the middle cerebral artery

    International Nuclear Information System (INIS)

    Four cases were presented who developed severe neurological deficits due to the embolic occlusion of the middle cerebral artery but who were successfully treated by embolectomy within 5 to 12 hours after their stroke. The postoperative results were excellent in three cases and good in one. We retrospectively investigated changes in serial CT findings taken pre- and postoperatively in order to examine the effectiveness of this procedure. In three of the cases examined, a preoperative CT scan taken within 6 hours after onset showed noremarkable change attributable to the middle cerebral occlusion. Postoperatively, one case developed a high-density spot in an ischemic low-density area regarded as an hemorrhagic infarction on the CT scan. The serial changes in the CT findings in the other three cases were divided into five stages. On the 5th to 10th postoperative day, moderate mass effects suggesting a brain edema were seen, with transient neurological deterioration; active treatment of these brain edema was quite important to obtain good results. These results suggest that the embolectomy of the middle cerebral artery during actute periods was effective in preventing severe neurological deficits, but was unable to prevent the appearance of a low-density area on the CT scan. A careful observation of the serial CT scans was very useful for making a prognosis and determining adequate postoperative treatment. (J.P.N.)

  13. Changes in CT scan following acute embolectomy of the middle cerebral artery

    Energy Technology Data Exchange (ETDEWEB)

    Baba, Hiroshi; Ono, Hirohisa; Mori, Kazuo (Nagasaki Univ. (Japan). School of Medicine); Kaneko, Mitsuo

    1982-10-01

    Four cases were presented who developed severe neurological deficits due to the embolic occlusion of the middle cerebral artery but who were successfully treated by embolectomy within 5 to 12 hours after their stroke. The postoperative results were excellent in three cases and good in one. We retrospectively investigated changes in serial CT findings taken pre- and postoperatively in order to examine the effectiveness of this procedure. In three of the cases examined, a preoperative CT scan taken within 6 hours after onset showed no remarkable change attributable to the middle cerebral occlusion. Postoperatively, one case developed a high-density spot in an ischemic low-density area regarded as an hemorrhagic infarction on the CT scan. The serial changes in the CT findings in the other three cases were divided into five stages. On the 5th to 10th postoperative day, moderate mass effects suggesting a brain edema were seen, with transient neurological deterioration; active treatment of these brain edema was quite important to obtain good results. These results suggest that the embolectomy of the middle cerebral artery during actute periods was effective in preventing severe neurological deficits, but was unable to prevent the appearance of a low-density area on the CT scan. A careful observation of the serial CT scans was very useful for making a prognosis and determining adequate postoperative treatment.

  14. The added diagnostic value of SPECT/CT imaging for bone metastases from lung cancer

    International Nuclear Information System (INIS)

    Objective: To investigate the added diagnostic value of SPECT/CT imaging over routine planar whole-body bone scintigraphy (WBBS) for bone metastases from lung cancer. Methods: One hundred and forty-six patients with lung cancer, confirmed by pathological examination, underwent routine 99Tcm-MDP (1110 MBq) WBBS, followed by SPECT/CT over the regions with indeterminate findings on WBBS. Both WBBS and bone SPECT/CT images were interpreted by two experienced nuclear medicine physicians in consensus as the positive, negative or uncertain bone metastases. The final diagnosis was com-firmed by pathology or clinical follow-up. χ2 test was used to compare the differences between the two imaging methods. Results: Finally, 45 patients were diagnosed as positive bone metastases and the other 101 as negative. The diagnostic sensitivity of bone SPECT/CT for bone metastases from lung cancer was 93.3% (42/45), significantly higher than that of WBBS (64.4%, 29/45) (χ2=19.944, P<0.05). The diagnostic accuracy of bone SPECT/CT was 89.7% (131/146), much higher than that of WBBS (44.5%, 65/146) (χ2=69.598, P<0.05). The uncertain and incorrect diagnostic rates of bone SPECT/CT and WBBS were 10.3% (15/146, raging from 5.3% to 15.2% with 95% confidence interval (CI)) and 55.5% (81/146, raging from 47.4% to 63.5% with 95% CI), respectively. Conclusion: Bone SPECT/CT provides incremental diagnostic value over routine WBBS for bone metastases from lung cancer. (authors)

  15. Usefulness of 18F FDG PET/CT for the evaluation of bone marrow involvement in patients with high grade non Hodgkin's lymphoma

    International Nuclear Information System (INIS)

    To assess the usefulness of 18F fluorodeoxyglucose PET/CT in the detection of bone marrow (BM) involvement of high grade non Hodgkin's lymphoma (NHL). One hundred twenty patients with newly diagnosed nosed diffuse large b cell lymphoma or peripheral t cell lymphoma between January 2007 and dune 2011, who re received bw trephine biopsy and 18F FDG PET/CT images and bone marrow biopsy (BMB) results. After reviewing the images, we reviewed the medical records and radiological findings of interesting patients. There were 23 18F FDG PET/CT scans in which the marrow was considered to be abnormal (either positive or equivocal), and 97 18F FDG PET/CT scans were regarded as having negative FDG uptake. Of 120 patients, 100 (83.3%) had a concordant result of BM interpretation between 18F FDG PET/CT and BMB, and the remaining 20 patients had discordant results. Among 23 patients with either positive or equivocal 18F FDG PET/CT scans, 1 of 12 patients with 'positive' 18F FDG PET/CT had a lymphomatous involvement on BMB. In contrast, 10 of 11 patients with 'equivocal' BM hypermetabolism were reported as having positive involvement on BMB. Patients with abnormal 18F FDG PET/CT had significantly higher mSUVhighestthan those with normal FDG PET/CT. 18F FDG PET/CT and BMB are complementary techniques in assessing the presence of BM involvement in patients with high grade NHL. the increasing availability of 18F FDG PET/CT will raise the need for additional biopsy for FDG avid lesions, especially in patients with negative standard BMBs 18F FDG PET/CT can be useful as a decision as an initial staging procedure. a direct bone biopsy for FDG avid lesion as an initial staging procedure. a direct bone biopsy for FDG positive bone lesions should be included in staging guidelines in future. In 18F FDG PET/CT negative cases, BMB is still a powerful procedure, but BMB alone is insufficient for full evaluation of BM

  16. Usefulness of {sup 18}F FDG PET/CT for the evaluation of bone marrow involvement in patients with high grade non Hodgkin's lymphoma

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Yukyung; Hwang, Kyung Hoon; Hong, Jun Shik; Park, Jinny; Lee, Jae Hoon; Ahn, Jeong Yeal; Kim, Ji Hyun; Lee, Hae Jun; Kim, Seog Gyun; Shin, Ji Young [Gachon Univ. Gil Hospital, Incheon (Korea, Republic of)

    2012-12-15

    To assess the usefulness of {sup 18}F fluorodeoxyglucose PET/CT in the detection of bone marrow (BM) involvement of high grade non Hodgkin's lymphoma (NHL). One hundred twenty patients with newly diagnosed nosed diffuse large b cell lymphoma or peripheral t cell lymphoma between January 2007 and dune 2011, who re received bw trephine biopsy and {sup 18}F FDG PET/CT images and bone marrow biopsy (BMB) results. After reviewing the images, we reviewed the medical records and radiological findings of interesting patients. There were 23 {sup 18}F FDG PET/CT scans in which the marrow was considered to be abnormal (either positive or equivocal), and 97 {sup 18}F FDG PET/CT scans were regarded as having negative FDG uptake. Of 120 patients, 100 (83.3%) had a concordant result of BM interpretation between {sup 18}F FDG PET/CT and BMB, and the remaining 20 patients had discordant results. Among 23 patients with either positive or equivocal {sup 18}F FDG PET/CT scans, 1 of 12 patients with 'positive' {sup 18}F FDG PET/CT had a lymphomatous involvement on BMB. In contrast, 10 of 11 patients with 'equivocal' BM hypermetabolism were reported as having positive involvement on BMB. Patients with abnormal {sup 18}F FDG PET/CT had significantly higher mSUV{sup highestt}han those with normal FDG PET/CT. {sup 18}F FDG PET/CT and BMB are complementary techniques in assessing the presence of BM involvement in patients with high grade NHL. the increasing availability of {sup 18}F FDG PET/CT will raise the need for additional biopsy for FDG avid lesions, especially in patients with negative standard BMBs {sup 18}F FDG PET/CT can be useful as a decision as an initial staging procedure. a direct bone biopsy for FDG avid lesion as an initial staging procedure. a direct bone biopsy for FDG positive bone lesions should be included in staging guidelines in future. In {sup 18}F FDG PET/CT negative cases, BMB is still a powerful procedure, but BMB alone is insufficient

  17. Impact of low-dose CT scan in dual timepoint investigations: a phantom study

    Science.gov (United States)

    Micheelsen, M. A.; Jensen, M.

    2011-09-01

    Dual timepoint FDG takeup investigations have a potential for separating malignant lymph nodes from non-malignant in certain cases of suspected lung cancer. One hour seems to be the optimal time interval between the two scans (50-120 min). Many of the new PET scanners benefit from image fusion with a CT image and also use the CT for attenuation correction. In any practical hospital setting, 1 hour is too long to occupy the scanner bed and a second CT procedure thus becomes necessary. This study tries to validate to what extent the dose/quality of the second CT scan can be lowered, without compromising attenuation correction, lesion detection and quantification. Using a standard NEMA phantom with the GE Discovery PET/CT scanner, taken in and out between scan sessions, we have tried to find the minimal CT dose necessary for the second scan while still reaching tissue activity quantification within predetermined error limits. For a hot sphere to background activity concentration ratio of 1:5, the average uptake (normalised by the time corrected input activity concentration) in a sphere of 6 cm3 was found to be 0.90 ± 0.08 for the standard scan, yielding a dose of 5.5 mGy, and 0.90 ± 0.14 for a scan with lowest possible mAs product and lowest possible kV, yielding a dose of 0.65 mGy. With an insignificant increase in the uncertainty in the uptake measurement, we can get an order of magnitude reduction for the CT dose.

  18. Characteristic of muscle involvement evaluated by CT scans in early stages of progressive muscular dystrophy

    International Nuclear Information System (INIS)

    Muscle CT scans were performed in order to compare the characteristic distribution of progressive muscle involvement in the early stages of Duchenne type (DMD) and Fukuyama type muscular dystrophy (FCMD). Muscle images at the levels of the 3rd lumbar vertebra, thigh and calf were assessed by visual inspection, and mean CT numbers calculated for individual muscles were statistically analysed. On visual inspection, intramuscular low density areas and muscular atrophy were observed in the muscles of older patients with either disease. These changes were, however, more extensive at thigh level in DMD, and at calf level in FCMD. Nevertheless, the mean CT numbers of muscles in which only slight changes were grossly visible on CT scans displayed progressive decreases with increasing age. Moreover, a significant negative relationship was recognizable between age and mean CT number in almost all muscles examined. Comparison of the slopes of the regression lines revealed that the so-called selective pattern of muscle involvement characteristic of the symptomatic stage had already partially manifested in the preclinical or early stages of both diseases. In FCMD, the rates of decrease in CT numbers were extremely rapid for calf muscles as compared with those in DMD, indicating that this is one reason for FCMD patients never becoming ambulatory. However, for almost all of the other muscles, the CT numbers in FCMD decreased in parallel with the corresponding CT numbers in DMD; thus, these diseases displayed a similarity in the pattern of muscle involvement, despite their different pathogenetic mechanisms and inheritance patterns. (author)

  19. Clinical utility of 18 Fluorodeoxyglucose (FDG-PET/CT scans in patients with suspect ocular tuberculosis

    Directory of Open Access Journals (Sweden)

    Salil Mehta

    2013-01-01

    Full Text Available Systemic imaging of patients with suspect ocular tuberculosis include chest X-rays and computed tomography (CT scans. Reports have suggested a role for 18 fluorodeoxyglucose-positron emission tomography/CT (FDG-PET/CT scans. We report on the clinical utility of 18 FDG PET/CT in two patients. Case 1: A 38-year-old female patient presented with recurrent anterior uveitis. A 18 FDG-PET scan revealed metabolically active supraclavicular and chest lymph nodes. An aspiration cytology of the cervical lymph node revealed caseating granulomas suggestive of tuberculosis. Case 2: A 58-year-old female patient presented with recurrent anterior uveitis. A 18 FDG-PET scan revealed metabolically active lymph nodes in the neck. A biopsy of the cervical lymph node revealed epithelioid granulomas suggestive of tuberculosis. Both patients were started on standard antitubercular therapy with a subsequent marked reduction of activity. PET/CT scans may suggest the sites of safe high-yield biopsies.

  20. Single energy micro CT SkyScan 1173 for the characterization of urinary stone

    Science.gov (United States)

    Fitri, L. A.; Asyana, V.; Ridwan, T.; Anwary, F.; Soekersi, H.; Latief, F. D. E.; Haryanto, F.

    2016-08-01

    A urinary stone is a solid piece of material produced from crystallization of excreted substances in the urine. Knowledge of the composition of urinary stones is essential to determine the suitable treatment for the patient. The aim of this research was to characterize urinary stones using single energy micro CT SkyScan 1173. Six human urinary stones were scanned in vitro using 80 kV in micro CT SkyScan 1173. The produced projection, images, were reconstructed using NRecon (in-house software from SkyScan). The images of urinary stones were analyzed using CT Analyser (CT An) to obtain information of the internal structure and the Hounsfield Unit (HU) value to determine the information regarding the composition of the urinary stones, respectively. The average HU values from certain region of interests in the same slice were compared with spectral curves of known materials from National Institute of Standards and Technology (NIST). From the analysis, the composition of the six scanned stones were obtained. Two stones are composed of cystine, two are composed of struvite, two other stones are composed of struvite+cystine. In conclusion, the single energy micro CT with 80 kV can be used identifying cystine and struvite urinary stone.

  1. Feasibility of iodine contrast enhanced CT-scan during a 18F-fluorodeoxyglucose Positron Emission Tomography

    Science.gov (United States)

    Houzard, C.; Tychyj, C.; Morelec, I.; Ricard, F.; Got, P.; Cotton, F.; Giammarile, F.; Maintas, D.

    2009-06-01

    OBJECTIVE: this prospective study evaluates the feasibility in current clinical practice of contrast enhanced CT-scan for diagnosis purpose, performed during 18FDG PET-CT study with a PET/CT tomography. METHOD: 25 patients underwent FDG imaging for lymphoma staging. The PET scan was done immediately after the usual low dose CT (lCT). A second CT scan was consequently acquired, by using classical diagnosis CT parameters (dCT) and iodinated contrast. For each patient, all CT attenuation correction (CTAC) PET images were visually compared. Density in Hounsfield units (HU) and maximum Standardized Uptake Value (SUVmax) were then measured on different organs and up to 5 specific lymphoma localizations (total of 294 measurements). RESULTS: Visual analysis was similar for the 2 modalities, without discordant interpretation for the pathologic sites. SUVmax means and standard deviation of each organ for lCTAC and dCTAC were comparable. The equation of the fitted multiple linear regression model was: dCT=0.0748191 + 1.17024*lCT (98.71%; p CT scan, before the PET scan acquisition for lymphoma staging with this PET-CT scan, not affected by the height atomic number and elevated density. A great benefit is therefore obtained on diagnostic, logistic and radioprotection purposes.

  2. Pancreas tumor model in rabbit imaged by perfusion CT scans

    Science.gov (United States)

    Gunn, Jason; Tichauer, Kenneth; Moodie, Karen; Kane, Susan; Hoopes, Jack; Stewart, Errol E.; Hadway, Jennifer; Lee, Ting-Yim; Pereira, Stephen P.; Pogue, Brian W.

    2013-03-01

    The goal of this work was to develop and validate a pancreas tumor animal model to investigate the relationship between photodynamic therapy (PDT) effectiveness and photosensitizer drug delivery. More specifically, this work lays the foundation for investigating the utility of dynamic contrast enhanced blood perfusion imaging to be used to inform subsequent PDT. A VX2 carcinoma rabbit cell line was grown in the tail of the pancreas of three New Zealand White rabbits and approximately 3-4 weeks after implantation the rabbits were imaged on a CT scanner using a contrast enhanced perfusion protocol, providing parametric maps of blood flow, blood volume, mean transit time, and vascular permeability surface area product.

  3. Improving depiction of temporal bone anatomy with low-radiation dose CT by an integrated circuit detector in pediatric patients: a preliminary study.

    Science.gov (United States)

    He, Jingzhen; Zu, Yuliang; Wang, Qing; Ma, Xiangxing

    2014-12-01

    The purpose of this study was to determine the performance of low-dose computed tomography (CT) scanning with integrated circuit (IC) detector in defining fine structures of temporal bone in children by comparing with the conventional detector. The study was performed with the approval of our institutional review board and the patients' anonymity was maintained. A total of 86 children0.05). The low-dose CT images acquired with the IC detector provide better depiction of fine osseous structures of temporal bone than that with the conventional DC detector.

  4. An incidental finding of myocardial uptake on HDP bone scan

    International Nuclear Information System (INIS)

    Full text: A 75 year old male referred with a history of wrist pain for a HDP bone scan(700Mbq) had dynamic and blood pool images. A posterior sweep and planar images were performed after 2 hours. The scan demonstrated a fracture of the left radial styloid, other degenerative arthritis and diffuse tracer uptake throughout the myocardium. The differential diagnoses included cardiac amyloid, myocardial infarction (MI) and calcific pericarditis. The patient, a non insulin dependent diabetic with previous MI in 1978 and hypertension had nocturnal dyspnoea and no chest pain. Chest X-ray was normal. ECG revealed old inferior infarct. Echocardiography showed mild hypokinesis of the inferior wall, low normal LV contractility, normal pericardium and no evidence of amyloid. A Rest (400Mbq) / Stress(1200Mbq) Sestamibi(MIBI) was performed to assess status of ischaemic heart disease (IHD). The patient experienced leg fatigue and shortness of breath but no chest pain. Rest ECG showed sinus bradycardia with ST/T wave changes. Stress ECG showed ST segment depression (0.5mm). Planar and SPECT studies showed reversible perfusion defects in the anterior wall and apex with a fixed inferolateral defect. Gated SPECT showed normal wall motion apart from the inferolateral infarct. The exact cause of the HDP uptake in the myocardium is unknown. The echo findings exclude amyloid or pericarditis. The MIBI study confirmed a small inferolateral infarct and myocardial ischaemia in the anterior wall and apex. The scan has affected patient management by diagnosing a fracture of the radial styloid and confirming previous infarction and myocardial ischaemia. An open view must be taken of the cardiac HDP uptake. The most likely diagnosis in this patient is silent IHD, which has been demonstrated in one other case known to us

  5. Evaluation of K-wire fixation for nasal bone fractures using CT images

    International Nuclear Information System (INIS)

    A nasal bone fracture is the most common facial fracture. Successful treatment requires accurate diagnosis and careful surgical management. Fractures usually are diagnosed on the basis of macroscopic inspection and X-rays. In some cases, CT can be useful in diagnosis of nasal bone fractures because CT images have few shadows and consequently are of high contrast. The authors therefore utilized CT in the classification of 83 cases of nasal bone fractures. CT also was used in 36 cases for postoperative evaluation. During the five-year period from 1989 to 1994, the authors diagnosed 83 cases of nasal bone fractures. CT findings were used to evaluate the types of fractures, which were classified as lateral (unilateral and bilateral), frontal, and lateral-frontal mixed. Included were 22 cases of unilateral fracture, 26 cases of bilateral fracture, 25 cases of frontal fracture, and 8 cases of frontal-lateral fracture. The authors performed closed reduction utilizing K-wire fixation under general anesthesia. Reduction resulted in an angle of θ formed between the nasal bone and maxillary bone, and with its apex at the fracture point. Of the 36 cases postoperatively evaluated by CT, 11 showed excellent results, 12 good results, and 13 fair results. Eleven of the 13 fair reduction cases had a free bone at the fracture point. Five of the 6 cases of fair reduction lateral-frontal mixed fractures had a free bone at the fracture point. Based on CT findings, the authors concluded that reduction and fixation utilizing K-wire was insufficient in cases with free bone fragments. It therefore is important that the existence and position of any free bone fragment should be given careful consideration before undertaking surgery. (author)

  6. TH-C-18A-02: Machine Learning and STAPLE Based Simultaneous Longitudinal Segmentation of Bone and Marrow Structures From Dual Energy CT

    Energy Technology Data Exchange (ETDEWEB)

    Fehr, D; Schmidtlein, C; Hwang, S; Deasy, J; Veeraraghavan, H [Memorial Sloan Kettering Cancer Center, New York, NY (United States)

    2014-06-15

    Purpose: To develop a fully-automatic longitudinal bone and marrow segmentation method in the pelvic region from dual energy computed tomography (DECT). Methods: We developed a two-step automatic bone and marrow segmentation method for simultaneous longitudinal evaluation of patients with metastatic bone disease using dual energy CT (DECT). Our approach transforms the DECT images into a multi-material decomposition (MMD) model that represents the voxels as a mixture of multiple materials. A support vector machine (SVM) was trained using a single scan. In the first step of the longitudinal segmentation the trained SVM model detects bone and marrow structures on all available longitudinal scans. Segmentation is further refined through active contour segmentation. In the second step, the segmentations from the individual scans are merged by employing the simultaneous truth and performance level estimation (STAPLE) algorithm. The scans are registered using affine and deformable registration. We found that our approach improves the segmentation in all the scans under reliable registration performance between the same scans. Improving registration was not under the scope of this work. Results: We applied our approach to segment bone and marrow in DECT scans in the pelvic regions for multiple patients. Each patient had three to five follow up scans. All the patients in the analysis had artificial metal prostheses which introduced challenges for the registration. Our algorithm achieved reasonable accurate segmentation despite the presence of metal artifacts and high-density oral contrast in neighboring structures. Our approach obtained an overall segmentation accuracy of 80% using DICE metric. Conclusion: We developed a two-step automatic longitudinal segmentation technique for bone and marrow region structures in the pelvic areas from dual energy CT. Our approach achieves robust segmentation despite the presence of confounding structures with similar intensities as the

  7. TH-C-18A-02: Machine Learning and STAPLE Based Simultaneous Longitudinal Segmentation of Bone and Marrow Structures From Dual Energy CT

    International Nuclear Information System (INIS)

    Purpose: To develop a fully-automatic longitudinal bone and marrow segmentation method in the pelvic region from dual energy computed tomography (DECT). Methods: We developed a two-step automatic bone and marrow segmentation method for simultaneous longitudinal evaluation of patients with metastatic bone disease using dual energy CT (DECT). Our approach transforms the DECT images into a multi-material decomposition (MMD) model that represents the voxels as a mixture of multiple materials. A support vector machine (SVM) was trained using a single scan. In the first step of the longitudinal segmentation the trained SVM model detects bone and marrow structures on all available longitudinal scans. Segmentation is further refined through active contour segmentation. In the second step, the segmentations from the individual scans are merged by employing the simultaneous truth and performance level estimation (STAPLE) algorithm. The scans are registered using affine and deformable registration. We found that our approach improves the segmentation in all the scans under reliable registration performance between the same scans. Improving registration was not under the scope of this work. Results: We applied our approach to segment bone and marrow in DECT scans in the pelvic regions for multiple patients. Each patient had three to five follow up scans. All the patients in the analysis had artificial metal prostheses which introduced challenges for the registration. Our algorithm achieved reasonable accurate segmentation despite the presence of metal artifacts and high-density oral contrast in neighboring structures. Our approach obtained an overall segmentation accuracy of 80% using DICE metric. Conclusion: We developed a two-step automatic longitudinal segmentation technique for bone and marrow region structures in the pelvic areas from dual energy CT. Our approach achieves robust segmentation despite the presence of confounding structures with similar intensities as the

  8. Optimal scan time for evaluation of parathyroid adenoma with [18F]-fluorocholine PET/CT

    Directory of Open Access Journals (Sweden)

    Rep Sebastijan

    2015-12-01

    Full Text Available Background. Parathyroid adenomas, the most common cause of primary hyperparathyroidism, are benign tumours which autonomously produce and secrete parathyroid hormone. [18F]-fluorocholine (FCH, PET marker of cellular proliferation, was recently demonstrated to accumulate in lesions representing enlarged parathyroid tissue; however, the optimal time to perform FCH PET/CT after FCH administration is not known. The aim of this study was to determine the optimal scan time of FCH PET/CT in patients with primary hyperparathyroidism.

  9. Lung nodule detection in low-dose and high-resolution CT scans

    CERN Document Server

    Delogu, P; Gori, I; Preite Martínez, A; Retico, A; Tata, A

    2006-01-01

    We are developing a computer-aided detection (CAD) system for the identification of small pulmonary nodules in screening CT scans. The main modules of our system, i.e. a dot-enhancement filter for nodule candidate selection and a neural classifier for false positive finding reduction, are described. The preliminary results obtained on the so-far collected database of lung CT are discussed.

  10. Efficacy of plain radiographs, CT scan, MRI and ultra sonography in temporomandibular joint disorders

    OpenAIRE

    Vijai P. Sinha; Pradhan, Harsha; Gupta, Hemant; Mohammad, Shadab; Singh, R. K.; Mehrotra, Divya; M C Pant; Pradhan, R

    2012-01-01

    The complexity of structure and functions of the Temporomandibular Joint (TMJ) make the diagnosis of its diseases/disorders difficult. Remarkable progress made in the field of imaging of this joint led us to compare four imaging modalities viz. plain radiographs, CT scan, MRI and ultrasound. We found that MRI was most specific and sensitive for interpretation of soft tissue and inflammatory conditions in the joint, whereas CT examination produced excellent image for osseous morphology and pat...

  11. Serial CT scans of cerebral hypoxia due to prolonged status epilepticus

    Energy Technology Data Exchange (ETDEWEB)

    Saiwai, Shigeo; Matsumura, Yasumasa; Tamaoka, Koichi; Fukuda, Teruo; Miyamoto, Takeshi (Kobe Central Municipal Hospital, Kobe (Japan))

    1983-04-01

    Serial computed tomography (CT) scans of 5 infants with status epilepticus were reviewed. Four out of the 5 infants fortunately had CT scans before status epilepticus because of a convulsion. There was a diffuse and mild low density in the hemisphere, with small ventricles and tight sulci (brain swelling) at 1 to 2 days after ictus. Thereafter, a diffuse low density became apparent except for the cerebellum, the brain stem, the thalamus, and the basal ganglia. Two to 4 weeks after ictus, a localized, mottled low density was demonstrated on the cerebral mantle and atrophic changes became progressively clear. In 3 cases, no abnormal enhancement was elicited on contrast CT scans performed between 5 to 16 days after status epilepticus. We discussed the possible pathophysiological aspects of the brain damage due to ''prolonged status epilepticus.''

  12. Radiographic skeletal survey and radionuclide bone scan in Langerhans cell histiocytosis of bone

    Energy Technology Data Exchange (ETDEWEB)

    Nieuwenhuyse, J.P. van [Department of Radiology and Medical Imaging, Cliniques Universitaires St-Luc, University of Louvain Medical School, Brussels (Belgium); Clapuyt, P. [Department of Radiology and Medical Imaging, Cliniques Universitaires St-Luc, University of Louvain Medical School, Brussels (Belgium); Malghem, J. [Department of Radiology and Medical Imaging, Cliniques Universitaires St-Luc, University of Louvain Medical School, Brussels (Belgium); Everarts, P. [Department of Radiology and Medical Imaging, Cliniques Universitaires St-Luc, University of Louvain Medical School, Brussels (Belgium); Melin, J. [Department of Nuclear Medicine, Cliniques Universitaires St-Luc, University of Louvain Medical School, Brussels (Belgium); Pauwels, S. [Department of Nuclear Medicine, Cliniques Universitaires St-Luc, University of Louvain Medical School, Brussels (Belgium); Brichard, B. [Department of Pediatric Hematology, Cliniques Universitaires St-Luc, University of Louvain Medical School, Brussels (Belgium); Ninane, J. [Department of Pediatric Hematology, Cliniques Universitaires St-Luc, University of Louvain Medical School, Brussels (Belgium); Vermylen, C. [Department of Pediatric Hematology, Cliniques Universitaires St-Luc, University of Louvain Medical School, Brussels (Belgium); Cornu, G. [Department of Pediatric Hematology, Cliniques Universitaires St-Luc, University of Louvain Medical School, Brussels (Belgium)

    1996-10-01

    Background. The lack of a consensus in the literature on the imaging strategy in Langerhans cell histiocytosis (LCH) bone lesions in childhood. Objective. To evaluate the relative value of radionuclide bone scan (RBS) and radiographic skeletal survey (RSS) in the detection of LCH bone lesions, both in the initial work-up of the disease and during the follow-up period. Materials and methods. Ten children with bone lesions evaluated by means of RSS and RBS in a retrospective study (1984-1993). Results. Fifty radiologically and/or scintigraphically abnormal foci were detected: 27 anomalies in the initial work-up (12 by both RSS and RBS, 8 by RSS only and 7 by RBS only) and 23 additional anomalies during follow-up (10 by both RSS and RBS, 10 by RSS only and 3 by RBS only). RSS+/RBS- lesions (n = 18) are more frequently encountered in the skull (P = 0.038), and more frequently lack radiologic signs of osteoblastic activity (P = 0.020), than RSS+/RBS+ lesions (n = 22). RSS-/RBS+ abnormalities (n = 10) were most frequently insignificant. Conclusion. In the initial work-up both RSS and RBS should be carried out, while in the follow-up only RSS should be performed. (orig.). With 2 figs., 4 tabs.

  13. Radiographic skeletal survey and radionuclide bone scan in Langerhans cell histiocytosis of bone

    International Nuclear Information System (INIS)

    Background. The lack of a consensus in the literature on the imaging strategy in Langerhans cell histiocytosis (LCH) bone lesions in childhood. Objective. To evaluate the relative value of radionuclide bone scan (RBS) and radiographic skeletal survey (RSS) in the detection of LCH bone lesions, both in the initial work-up of the disease and during the follow-up period. Materials and methods. Ten children with bone lesions evaluated by means of RSS and RBS in a retrospective study (1984-1993). Results. Fifty radiologically and/or scintigraphically abnormal foci were detected: 27 anomalies in the initial work-up (12 by both RSS and RBS, 8 by RSS only and 7 by RBS only) and 23 additional anomalies during follow-up (10 by both RSS and RBS, 10 by RSS only and 3 by RBS only). RSS+/RBS- lesions (n = 18) are more frequently encountered in the skull (P = 0.038), and more frequently lack radiologic signs of osteoblastic activity (P = 0.020), than RSS+/RBS+ lesions (n = 22). RSS-/RBS+ abnormalities (n = 10) were most frequently insignificant. Conclusion. In the initial work-up both RSS and RBS should be carried out, while in the follow-up only RSS should be performed. (orig.). With 2 figs., 4 tabs

  14. 68Ga-DOTATATE positron emission tomography/computed tomography scan in the detection of bone metastases in pediatric neuroendocrine tumors

    OpenAIRE

    Goel, Reema; Shukla, Jaya; Bansal, Deepak; Sodhi, Kushaljit; Bhattacharya, Anish; Marwaha, Ram Kumar; Mittal, Bhagwant Rai

    2014-01-01

    Aim: The aim of this study is to evaluate the role of 68Ga-DOTATATE positron emission tomography/computed tomography (PET/CT) scan for the detection of bone metastases in pediatric neuroendocrine tumors (NETs) and to compare it with CT scan. Materials and Methods: A total of 30 patients (18 were males and 12 were females; age range: 1-18 years; mean age 7.6 years) with histologically confirmed NETs referred to our department were retrospectively analyzed. All patients underwent 68Ga-DOTATATE ...

  15. The evaluation of CT scan in renal involvement of children with non-Hodgkin's lymphoma

    International Nuclear Information System (INIS)

    Objective: To understand the incidence of renal involvement of children with non-Hodgkin's lymphoma and to recognize its different CT findings. Methods: The thoracic and abdominal plain and contrast enhanced CT of 30 cases of NHL in children were reviewed and all cases were confirmed by pathology. The changes in both pre- and post chemotherapy were analysed in the 10 selected cases with renal involvement. Results: CT demonstrated 6 cases of multiple masses and 1 case of multiple patchy lesions in bilateral kidneys. Two cases of single mass and 1 case of multiple masses were detected in single kidney. Conclusion: The incidence of renal involvement of children with non-Hodgkin's lymphoma is relatively high. CT can clearly demonstrate the renal involvement of NHL, which is helpful for clinical stage, especially in the evaluation of the therapeutic effects. Hence, abdominal plain and contrast-enhanced CT scan should be done in children with NHL

  16. CCD-based optical CT scanning of highly attenuating phantoms

    Energy Technology Data Exchange (ETDEWEB)

    Al-Nowais, Shamsa [Department of Physics, University of Surrey, Guildford (United Kingdom); Doran, Simon J [CRUK Clinical MR Research Group, Institute of Cancer Research, Sutton (United Kingdom)], E-mail: Simon.Doran@icr.ac.uk

    2009-05-01

    The introduction of optical computed tomography (optical-CT) offers economic and easy to use 3-D optical readout for gel dosimeters. However, previous authors have noted some challenges regarding the accuracy of such imaging techniques at high values of optical density. In this paper, we take a closer look at the 'cupping' artefact evident in both light-scattering polymer systems and highly light absorbing phantoms using our CCD-based optical scanner. In addition, a technique is implemented whereby the maximum measurable optical absorbance is extended to correct for any errors that may have occurred in the estimated value of the dark current or ambient light reaching the detector. The results indicate that for absorbance values up to 2.0, the optical scanner results have good accuracy, whereas this is not the case at high absorbance values for reasons yet to be explained.

  17. Radiation dose calculations for CT scans with tube current modulation using the approach to equilibrium function

    International Nuclear Information System (INIS)

    Purpose: The approach to equilibrium function has been used previously to calculate the radiation dose to a shift-invariant medium undergoing CT scans with constant tube current [Li, Zhang, and Liu, Med. Phys. 39, 5347–5352 (2012)]. The authors have adapted this method to CT scans with tube current modulation (TCM). Methods: For a scan with variable tube current, the scan range was divided into multiple subscan ranges, each with a nearly constant tube current. Then the dose calculation algorithm presented previously was applied. For a clinical CT scan series that presented tube current per slice, the authors adopted an efficient approach that computed the longitudinal dose distribution for one scan length equal to the slice thickness, which center was at z = 0. The cumulative dose at a specific point was a summation of the contributions from all slices and the overscan. Results: The dose calculations performed for a total of four constant and variable tube current distributions agreed with the published results of Dixon and Boone [Med. Phys. 40, 111920 (14pp.) (2013)]. For an abdomen/pelvis scan of an anthropomorphic phantom (model ATOM 701-B, CIRS, Inc., VA) on a GE Lightspeed Pro 16 scanner with 120 kV, N × T = 20 mm, pitch = 1.375, z axis current modulation (auto mA), and angular current modulation (smart mA), dose measurements were performed using two lines of optically stimulated luminescence dosimeters, one of which was placed near the phantom center and the other on the surface. Dose calculations were performed on the central and peripheral axes of a cylinder containing water, whose cross-sectional mass was about equal to that of the ATOM phantom in its abdominal region, and the results agreed with the measurements within 28.4%. Conclusions: The described method provides an effective approach that takes into account subject size, scan length, and constant or variable tube current to evaluate CT dose to a shift-invariant medium. For a clinical CT scan

  18. Overbeaming and overlapping of volume-scan CT with tube current modulation in a 320-detector row CT scanner

    International Nuclear Information System (INIS)

    The purpose of this study was to evaluate the performance of volume scan tube current modulation (VS-ATCM) with adaptive iterative dose reduction 3D (AIDR3D) technique in abdomen CT examinations. We scanned an elliptical cone-shaped phantom utilizing AIDR3D technique combined with VS-ATCM mode in a 320-detector row CT scanner. The image noise distributions with conventional filtered back-projction (FBP) technique and those with AIDR3D technique were compared. The radiation dose profile and tube current time product (mAs) in three noise levels of VS-ATCM modes were compared. The radiation beam profiles of five preset scan lengths were measured using Gafchromic film strips to assess the effects of overbeaming and everlapping. The results indicated that the image noises with AIDR3D technique was 13–74% lower than those in FBP technique. The mAs distributions can be a prediction for various abdominal sizes when undergoing a VS-ATCM mode scan. Patients can receive the radiation dose of overbeaming and overlapping during the VS-ATCM mode scans. - Highlights: • Noise reduction with AIDR3D in VS-ATCM is 13–74%. • We provide mAs prediction in VS-ATCM for all sizes. • We observe the effect of overbeaming and overlapping

  19. Automatic tube current modulation for volume scan in a 320-detector row CT scanner

    International Nuclear Information System (INIS)

    The x-y plane combined with z-axis automatic tube current modulation (ATCM) technique is one of the most comprehensive approaches to CT dose reduction because the radiation dose is adjusted according to patient attenuation in three dimensions. The 320-detector row CT scanner has the widest scan range (16 cm) within one axial rotation and equips with volume scan ATCM (VS-ATCM) mode. Special attention is needed while utilizing VS-ATCM mode in CT acquisitions especially scanning different anatomical regions, such as neck and shoulder in a single volume. However, the mechanism of VS-ATCM of the 320-detector row CT scanner remains unclear. This study aims to evaluate the performance of VS-ATCM mode in a 320-detector row CT scanner. A phantom set consists of three simple-shaped phantoms was scanned with the VS-ATCM mode. A solid-state detector was inserted into the central position of the phantom set to measure the real-time dose profiles at seven positions within five scan volumes. The effective tube-current time product of each slice was recorded. The standard deviation of the CT numbers measured at each image slice was used as a noise measurement. The performance of helical scan ATCM (HS-ATCM) mode was in comparison of VS-ATCM mode. The results indicated that VS-ATCM mode can provide a less dose CT scanning to a patient but resulted in a higher image noise in comparison with those of HS-ATCM mode. In clinical practice, radiologists or radiological technologists should pay more attention on the volume position when using VS-ATCM mode for patient imaging. Our experience can be a reference to others for implementation of clinical practices. -- Highlights: •Real-time dose profiles were measured for volume-scan ATCM mode. •Comparison of tube current variation between volume- and helical-scan ATCM modes. •Comparison of image noise between volume- and helical-scan ATCM modes

  20. Patient willingness and barriers to receiving a CT scan for lung cancer screening.

    Science.gov (United States)

    Delmerico, Jennifer; Hyland, Andrew; Celestino, Paula; Reid, Mary; Cummings, K Michael

    2014-06-01

    CT scans are becoming a more common method for detecting lung cancers at an earlier, potentially more curable, stage of disease. There is currently little data on attitudes and beliefs about screening for lung cancer. This paper presents the results of a 2011 survey of adult current and former smokers that queried about past use of CT scanning and reasons for having or not having the screening done. A random-digit dialed telephone survey was administered to a representative sample of 1290 US adults. Logistic regression analyses were used to examine the correlates of having the test while controlling for the covariates. A total of 13.4% (n = 45) of the sample had ever had a CT scan to detect lung cancer. Of current smokers, 14.6% had received a CT scan, as compared with 12.7% of former smokers. The oldest age group (55+) was significantly more likely to have received a CT scan than the younger age groups. 78.5% of current smokers and 81.4% of former smokers indicated willingness to get the test if advised to do so by their doctor. Among those who said they were not willing to get screened, lack of insurance coverage was cited by 33% of current smokers and 25% of former smokers. Additionally, 33% of current smokers were afraid to find out whether they had cancer. The main barrier to CT scanning for lung cancer is likely to be insurance coverage for the test, which would be a burden for those on limited and fixed incomes. Next steps should include further research into the effect of increased public education about the availability, risks, benefits and barriers to lung cancer screening. PMID:24674155

  1. Initial brain CT scan and shunting outcomes in children with hydrocephalus

    Directory of Open Access Journals (Sweden)

    Andi Anita Utami

    2013-04-01

    Full Text Available Background Hydrocephalus is one of the most common clinical conditions affecting the central nervous system, with a congenital hydrocephalus incidence of 3-4 per 1000 births. Incidence of acquired types of hydrocephalus is unknown. Brain computerised tomography (CT scan can be used to assess the size of ventricles and other structures. Shunting has long been performed to alleviate hydrocephalus. Shunting has dramatically changed the outlook of children with hydrocephalus, with many of them having normal life expectancies and attaining normal intelligence. Objective To determine the outcomes of shunting in children with hydrocephalus based on initial brain CT scan. Methods We performed a cross-sectional study in Dr. Kariadi Hospital. Initial brain CT scan data were collected from the medical records of children admitted to the Neurosurgery Ward for ventriculoperitoneal (VP shunt surgery from January 2009 to December 2010. We studied the brain CT scan findings before VP shunt surgery and the outcomes of the children after VP shunt surgery. Radiological findings were determined by a radiologist responsible at that time. Results This study consisted of 30 subjects, 19 boys and 11 girls. Initial brain CT scans to assess disease severity revealed the following conditions: lateral ventricle dilatation in 7 subjects, lateral and third ventricle dilatation in 16 subjects, and lateral, third and fourth ventricle dilatation in 7 subjects. After VP shunt surgery, 3 subjects in the lateral, third and fourth ventricle dilatation category died. They were grouped according to their condition. Group 1 consisted of subjects with only lateral ventricle dilatation and subjects with lateral and third ventricle dilatation (23 subjects, while group 2 consisted of subjects with lateral, third and fourth ventricle dilatation (7 subjects. More survivors were found in group 1 than those in group 2. Conclusion Less severe initial brain CT scan findings are associated with

  2. Detectability of the appendix with multidetector-row CT scanning and multiplanar reconstruction

    International Nuclear Information System (INIS)

    Twenty-six consecutive patients with the clinical diagnosis of appendicitis underwent multidetector-row CT (MD-CT) in order to detect entire longitudinal configuration of the appendix. While axial CT failed to detect the appendix in 7 patients, multiplanar reconstruction (MPR) demonstrated a longitudinal tubular structure continuous from the cecal caput in 25 patients (96.2%), including 7 patients whose post-surgical pathology were available. It is summarized that scanning and MPR images are advantageous to finding inflammatory processes in the appendix when the diagnosis of appendicitis remains ambiguous even with US. (author)

  3. Comparison of bone histomorphometry and μCT for evaluating bone quality in tail-suspended rats

    Science.gov (United States)

    Sun, Lian-Wen; Huang, Yun-Fei; Wang, Ying; Luan, Hui-Qin; Fan, Yu-Bo

    2014-10-01

    Astronauts often suffer from microgravity-induced osteoporosis due to their time in space. Bone histomorphometry, the 'gold standard' technique for detecting bone quality, is widely used in the evaluation of osteoporosis. This study investigates whether μCT has the same application value as histomorphometry in the evaluation of weightlessness-induced bone loss. A total of 24 SD rats were distributed into three groups (n = 8, each): tail-suspension (TS), TS plus active exercise (TSA), and control (CON). After 21 days, bone mineral density (BMD) was measured by dual energy X-ray absorptiometry (DXA) and μCT, and microstructure was measured by μCT and histomorphometry. BMD was found to have decreased significantly in TS and TSA compared with the CON group. The results of the μCT measurements showed that a change in BMD mainly occurred in the trabecular bone, and the trabecular BMD increased significantly in the TSA compared with the TS group. The comparison of μCT and histomorphometry showed that TS led to a significant decrease in bone volume (BV/TV), trabecular thickness (Tb.Th) and trabecular number (Tb.N), and it led to an increase in trabecular separation (Tb.Sp). However, active exercise can prevent these changes. Significant differences in most parameters between TSA and CON were found by μCT but not by histomorphometry. Additionally, the parameters of these two methods are highly correlated. Therefore, the application value of μCT is as good as histomorphometry and DXA in the diagnosis of weightlessness-induced osteoporosis and is even better in evaluating the efficacy of exercise.

  4. A vast increase in the use of CT scans for investigating occult hip fractures

    International Nuclear Information System (INIS)

    Background: Early diagnosis in neck of femur fractures has been shown to improve outcome. The National Institute for Clinical Excellence recommends if an occult hip fracture is suspected then an MRI should be performed and if not available within 24 h a CT should be considered. At our centre, emergency MRI is rarely available and so CT is commonly used. Objectives: Our study aims to analyse the trends in CT use over a five year period for the diagnosis of neck of femur fractures. Methods: Both the number of patients with a hip fracture and those undergoing a CT hip to diagnose an occult injury were identified across two district general hospitals between 2006–2007 and 2010–2011. The time from initial radiograph to CT and initial radiograph to operation were calculated. Results: In 2006–2007, of 547 hip fractures, 20 CT hips were performed and 6 reported as a fractured neck of femur (30%). In 2010–2011, of 499 hip fractures, 239 CT hips were performed and 65 fractures were recognised (27%). The mean time from radiograph until CT scan was 2.0 days in 2007 and 3.2 days in 2011, which was a statistically significant difference (p < 0.001). For those diagnosed using a CT scan the mean time from admission X-ray to surgery was 1.2 days in 2007 and 3.6 days in 2011. Conclusion: Clinicians are becoming increasingly reliant on CT for the diagnosis of hip fractures with our data suggesting further imaging is one factor that can delay time to diagnosis and theatre

  5. A vast increase in the use of CT scans for investigating occult hip fractures

    Energy Technology Data Exchange (ETDEWEB)

    Jordan, Robert, E-mail: Robert.jordan@doctors.org.uk; Dickenson, Edward, E-mail: edwarddickenson@doctors.org.uk; Westacott, Daniel, E-mail: dan_westacott@hotmail.com; Baraza, Njalalle, E-mail: njaleb@Doctors.Org.Uk; Srinivasan, Kuntrapka, E-mail: bijusri@Yahoo.Co.Uk

    2013-08-15

    Background: Early diagnosis in neck of femur fractures has been shown to improve outcome. The National Institute for Clinical Excellence recommends if an occult hip fracture is suspected then an MRI should be performed and if not available within 24 h a CT should be considered. At our centre, emergency MRI is rarely available and so CT is commonly used. Objectives: Our study aims to analyse the trends in CT use over a five year period for the diagnosis of neck of femur fractures. Methods: Both the number of patients with a hip fracture and those undergoing a CT hip to diagnose an occult injury were identified across two district general hospitals between 2006–2007 and 2010–2011. The time from initial radiograph to CT and initial radiograph to operation were calculated. Results: In 2006–2007, of 547 hip fractures, 20 CT hips were performed and 6 reported as a fractured neck of femur (30%). In 2010–2011, of 499 hip fractures, 239 CT hips were performed and 65 fractures were recognised (27%). The mean time from radiograph until CT scan was 2.0 days in 2007 and 3.2 days in 2011, which was a statistically significant difference (p < 0.001). For those diagnosed using a CT scan the mean time from admission X-ray to surgery was 1.2 days in 2007 and 3.6 days in 2011. Conclusion: Clinicians are becoming increasingly reliant on CT for the diagnosis of hip fractures with our data suggesting further imaging is one factor that can delay time to diagnosis and theatre.

  6. Pulmonary bone cement embolism: CT angiographic evaluation with material decomposition using gemstone special imaging

    Energy Technology Data Exchange (ETDEWEB)

    Huh, Sun; Lee, Heon [Dept. of Radiology, Soonchunhyang University Hospital Bucheon, Bucheon (Korea, Republic of)

    2014-08-15

    We report a case of pulmonary bone cement embolism in a female who presented with dyspnea following multiple sessions of vertebroplasty. She underwent spectral CT pulmonary angiography and the diagnosis was made based on enhanced visualization of radiopaque cement material in the pulmonary arteries and a corresponding decrease in the parenchymal iodine content. Here, we describe the CT angiography findings of bone cement embolism with special emphasis on the potential benefits of spectral imaging, providing additional information on the material composition.

  7. HT-BONE: a graphical user interface for the identification of bone profiles in CT images via extended Hough transform

    Science.gov (United States)

    Campi, Cristina; Perasso, Annalisa; Beltrametti, Mauro C.; Piana, Michele; Sambuceti, Gianmario; Massone, Anna Maria

    2016-03-01

    It has been recently proved that the computational analysis of X-ray Computed Tomography (CT) images allows clinicians to assess the alteration of compact bone asset due to hematological diseases. HT-BONE implements a new method, based on an extension of the Hough transform (HT) to a wide class of algebraic curves, for accurately measuring global and regional geometric properties of trabecular and compact bone districts. In the case of CT/PET analysis, the segmentation of the CT images provides masks for Positron Emission Tomography (PET) data, extracting the metabolic activity in the region surrounded by compact bone tissue. HT-BONE offers an intuitive, user-friendly, Matlab-based Graphical User Interface (GUI) for all input/output procedures and the automatic managing of the segmentation process also from non-expert users: the CT/PET data can be loaded and browsed easily and the only pre-preprocessing required from the user is the drawing of Regions Of Interest (ROIs) around the bone districts under consideration. For each bone district, specific families of curves, whose reliability has been already tested in previous works, is automatically selected for the recognition task via HT. As output, the software returns masks of the segmented compact bone regions, images of the Standard Uptake Values (SUV) in the masked regions of PET slices, and the values of the parameters in the curve equations utilized in the HT procedure. This information can be used for all pathologies and clinical conditions for which the alteration of the compact bone asset or bone marrow distribution plays a crucial role.

  8. CT scan findings of fungal pneumonia; Diagnose der Pilzpneumonie in der Thorax-CT

    Energy Technology Data Exchange (ETDEWEB)

    Heckmann, M.; Uder, M.; Bautz, W.; Heinrich, M. [Erlangen-Nuernberg Univ., Erlangen (Germany). Inst. fuer Diagnostische Radiologie

    2008-07-01

    The importance of fungal infection of the lung in immunocompromised patients has increased substantially during the last decades. Numerically the most patients are those with neutropenia, e.g. patients with malignancies or solid organ and stem cell transplantation, chemotherapy, corticosteroid use and HIV infection. Although fungal infections can occur in immunocompetent patients, their frequency in this population is rare. The clinical symptoms such as fever accompanied with non-productive cough are unspecific. In some patients progression to hypoxemia and dyspnea may occur rapidly. In spite of improved antifungal therapy morbidity and mortality of these infections are still high. Therefore an early and non-invasive diagnosis is very important. That is why CT and even better High-Resolution-CT (HR-CT) is a very important modality in examining immunocompromised patients with a probability of fungal infection. CT is everywhere available and, as a non-invasive method, able to give the relevant diagnose efficiently. This paper should give an overview about the radiologic findings and possible differential diagnosis of diverse pulmonary fungal infections in CT. Pneumonias caused by Aspergillus, Cryptococcus, Candida, Histoplasma, Mucor and Geotrichum capitatum are illustrated. (orig.)

  9. Congenital Pyloric Atresia with Distal Duodenal Atresia- Role of CT Scan

    Directory of Open Access Journals (Sweden)

    Yogender Singh Kadian

    2014-07-01

    Full Text Available The mainstay of diagnosis of congenital pyloric atresia is by plain X-ray of the abdomen showing a large gas bubble with no gas distally. But very rarely it can be associated with distal duodenal atresia when the baby may present as lump abdomen. In such a situation apart from the X-ray, another radiological investigation is needed to delineate the exact nature of the lump. Since the role of ultrasonography is limited in intestinal pathologies and contrast studies are not informative in atresias, the CT scan is the ideal choice. We had managed a case of pyloric atresia with similar presentation with preoperative CT scan.

  10. 3D quantification of soil structure and functioning based on PET and CT scanning techniques

    DEFF Research Database (Denmark)

    Garbout, Amin

    This thesis explores the potential of PET and CT scanning techniques to quantify and visualize soil structure, root development, and soil/plant interactions. At the investigated scale, these non-invasive and nondestructive techniques have some obvious advantages compared with most other techniques....... The processed measurements show some expected and a few unexpected effects (or lack of effects) on different characteristics of soil structure. The combination of CT and PET scanning in an air plant soil controller system revealed some very interesting research possibilities. Interactions between soil...

  11. Analisis Pengaruh Slice Thickness Terhadap Citra CT Scan Dengan Kasus Sinus Paranasal Pengguna Gigi Palsu Implan

    OpenAIRE

    Sinaga, Srituti

    2015-01-01

    Artifacts is a disturbance in the image display CT Scan . Has conducted a study on the analysis of effect image slice thickness CT Scan with cases of paranasal sinus users dentures implan. Slice thickness used is 1, 3, 5 and 7 mm. The riset in Radiology Pirngadi Hospital Medan. The results of research that the slice thickness of 1mm is 3,18D obtained a description of the larger artifacts, slice thickness 7 mm is 2,54D obtained a description of the artifacts on the wane ( a little ) and the si...

  12. Utility of CT scanning in anesthetic management for the patients with stenosis of the trachea

    International Nuclear Information System (INIS)

    The anesthetic management of six cases with tracheal stenosis due to goiter or mediastinal tumor was discussed in this paper. After evaluating not only the size and the transient shape of the trachea but also the quality and quantity of the tumor around the trachea by CT scanning, we could choose the optimal way of introduction and the size of endotracheal tube. If extreme stenosis of the trachea was revealed by CT scanning, awake intubation is preferred to prevent complications, which tended to occur during and after the induction of anesthesia with thiopental and succinylcholine chloride. (author)

  13. Growth plate closure: Apex view on bone scan

    International Nuclear Information System (INIS)

    Angular deformities of the extremities in children following premature closure of the growth plate are well known. The deformities depend on the position of an osseus bridge which forms between the epiphysis and metaphysis. Several surgical procedures including resection of the osseus bridge have been described, however, delineation of the site of fusion is difficult to define. The commonest site of growth plate arrest is the distal femoral or proximal tibial growth plate. A new technique using the bone scan has been developed which accurately defines the area and position of these osseus bridges. Two hours after injection of technetium 99m methylene diphosphonate apex views of the affected distal femoral growth plate were performed. The knee was flexed into its smallest angle. Using a pinhole collimator the gamma camera was angled to face the affected growth plate end on. The image was collected onto computer and analysed by: (I) regions of interest over segments of the growth plate to calculate the relative area of total growth plate affected: (II) generating histograms: (III) thresholding or performing isocontours to accentuate abnormal areas. The growth plate is normally uniformly increased when compared to the normal shaft of the bone. Fusion across the plate appears as an area of diminished uptake. The apex view gives a unique functional map of the growth plate such that abnormal areas are displayed, and the site, size and position of osseus fusion obtained. The technique has the potential for determining the metabolic activity of the growth plate before and after surgery. Serial studies will allow assessment of regneration of the plate and reformation of new osseus bridges

  14. Advanced material separation technique based on dual energy CT scanning

    Science.gov (United States)

    Zamyatin, Alexander A.; Natarajan, Anusha; Zou, Yu

    2009-02-01

    We propose a method for material separation using dual energy data. Our method is suitable to separation of three or more materials. In this work we describe our method and show results of numerical simulation and with real dual-energy data of a head phantom. The proposed method of constructing the material separation map consists of the following steps: Data-domain dual energy decomposition - Vector plot - Density plot - Clustering - Color assignment. Density plots are introduced to allow automatic cluster separation. We use special image processing methods, including Gaussian decomposition, to improve the accuracy of material separation. We also propose using the HSL color model for better visualization and to bring a new dimension in material separation display. We study applications of bone removal and virtual contrast removal. Evaluation shows improved accuracy compared to standard methods.

  15. Phantom studies using a high-resolution CT for ex-vivo imaging of degradable magnesium implants and simulated peri-implant bone formation in rabbit tibiae

    International Nuclear Information System (INIS)

    Purpose: Evaluation of the suitability of the high-resolution CT XtremeCT for ex vivo imaging of degradable magnesium implants with simulated peri-implant bone formation in rabbit tibiae and development of a method for calibrating the mass concentration of a magnesium alloy in an implant volume. Materials and Methods: Using specially designed phantoms, degradable magnesium implants of the alloys LAE442, ZEK100, AX30 and MgCa 0.8 %, without coating and with peri-implant bone formation simulated by a coating, as well as rabbit tibiae were scanned. CT numbers and the contrast-to-noise-ratio (CNR) of the studied materials were determined. The visual distinction between implant and coating was evaluated. To calibrate the implant density, exemplary LAE442 pins with different mass concentrations were scanned using a specially constructed phantom. Subsequently, CT numbers corresponding to the appropriate mass concentration were determined. Results: The implants, coating and substantia corticalis showed a similar density. Visual distinction between coating and implant was strongly dependent on the respective magnesium alloy and chosen scan parameter. A CNR of at least 0.2 was required for a distinction between implant and coating. For the mass concentration, a high CT number linearity (R2 = 0.99) throughout the measuring range (1811 - 1273 mg/cm3 LAE442) was found. Conclusion: As expected, the XtremeCT is primarily suitable for the imaging of bone tissue and implants. Good visual distinction of peri-implant bone formation on magnesium implants in an ex vivo phantom model ranges from possible to difficult depending on the bone density and alloy composition. (orig.)

  16. The use of the HiSPECT bone scan in canine flexor enthesopathy and coronoid pathology.

    Science.gov (United States)

    Peremans, K; Duchateau, L; Vermeire, S; Vandermeulen, E; Dobbeleir, A; Gielen, I; Polis, I; Van Rijssen, B; De Bakker, E; Saunders, J; De Spiegeleer, B; Dik, K

    2013-06-01

    In this study the use of the high resolution Micro-Single Photon Emission Tomography (HiSPECT) system with a radioactive bonemarker, (99m)Tc-oxidronate, was evaluated in dogs with coronoid pathology and/or flexor enthesopathy. Sixty-five elbows of 34 dogs were included. CT and HiSPECT were performed on all elbows, arthroscopy on 59. Tracer uptake in 8 anatomical regions was graded according to two models. Increased activity in the medial epicondylar region was associated with flexor pathology on CT (P=0.0002) and arthroscopy (P<0.0001) and increased uptake in the medial coronoid (P<0.0001) and the medial condylar area (P<0.013) with coronoid pathology. Uptake in the remaining areas was not associated with both pathologies. In conclusion, the improved resolution of the HiSPECT system allows identification of increased tracer uptake in the anatomical regions involved in coronoid pathology and flexor enthesopathy. This modality may improve the diagnostic potential of the bone scan in canine elbow disease.

  17. X-ray CT high-density artefact suppression in the presence of bones

    Energy Technology Data Exchange (ETDEWEB)

    Wei Jikun [School of Health Sciences, 550 Stadium Mall Drive, West Lafayette, IN 47907-2051 (United States); Chen Laigao [BioImaging Center of Emphasis, Pfizer Global Research and Development, 2800 Plymouth RD, Ann Arbor, MI 48105 (United States); Sandison, George A [School of Health Sciences, 550 Stadium Mall Drive, West Lafayette, IN 47907-2051 (United States); Liang Yun [Department of Radiology, Indiana University Medical School, Indianapolis, IN 46202 (United States); Xu, Lisa X [School of Mechanical Engineering, 585 Purdue Mall, West Lafayette, IN 47907-2040 (United States)

    2004-12-21

    This paper presents a novel method of reducing x-ray CT high-density artefacts generated by metal objects when abundant bone structures are present in the region of interest. This method has an advantage over previously proposed methods since it heavily suppresses the metal artefacts without introducing extra bone artefacts. The method of suppression requires that bone pixels are isolated and segmented by thresholding. Then artificial CT numbers are assigned to the bone pixels so that their projection profiles are smooth and thus can be properly simulated by a polynomial interpolation. The projection profile of the metal object is then removed to fully suppress the artefacts. The resulting processed profile is fed to a reconstruction routine and the previously preserved bone pixels added back. The new method utilizes two important features of the CT image with metal artefacts: (a) metal and bone pixels are not severely affected by the high-density artefacts and (b) the high-density artefacts can be located in specific projection channels in the profile domain, although they are spread out in the image domain. This suppression method solves the problem of CT image artefacts arising from metal objects in the body. It has the potential to greatly improve diagnostic CT imaging in the presence of these objects and treatment planning that utilizes CT for patients with metal applicators (e.g., brachytherapy for cervix cancer and prostate cryotherapy)

  18. X-ray CT high-density artefact suppression in the presence of bones

    International Nuclear Information System (INIS)

    This paper presents a novel method of reducing x-ray CT high-density artefacts generated by metal objects when abundant bone structures are present in the region of interest. This method has an advantage over previously proposed methods since it heavily suppresses the metal artefacts without introducing extra bone artefacts. The method of suppression requires that bone pixels are isolated and segmented by thresholding. Then artificial CT numbers are assigned to the bone pixels so that their projection profiles are smooth and thus can be properly simulated by a polynomial interpolation. The projection profile of the metal object is then removed to fully suppress the artefacts. The resulting processed profile is fed to a reconstruction routine and the previously preserved bone pixels added back. The new method utilizes two important features of the CT image with metal artefacts: (a) metal and bone pixels are not severely affected by the high-density artefacts and (b) the high-density artefacts can be located in specific projection channels in the profile domain, although they are spread out in the image domain. This suppression method solves the problem of CT image artefacts arising from metal objects in the body. It has the potential to greatly improve diagnostic CT imaging in the presence of these objects and treatment planning that utilizes CT for patients with metal applicators (e.g., brachytherapy for cervix cancer and prostate cryotherapy)

  19. Colon distension and scan protocol for CT-colonography: An overview

    Energy Technology Data Exchange (ETDEWEB)

    Boellaard, Thierry N., E-mail: t.n.boellaard@amc.uva.nl [Department of Radiology, Academic Medical Center, University of Amsterdam, PB 22660, 1100 DD Amsterdam (Netherlands); Haan, Margriet C. de, E-mail: m.c.dehaan@amc.uva.nl [Department of Radiology, Academic Medical Center, University of Amsterdam, PB 22660, 1100 DD Amsterdam (Netherlands); Venema, Henk W., E-mail: h.w.venema@amc.uva.nl [Department of Radiology, Academic Medical Center, University of Amsterdam, PB 22660, 1100 DD Amsterdam (Netherlands); Department of Biomedical Engineering and Physics, Academic Medical Center, University of Amsterdam, PB 22660, 1100 DD Amsterdam (Netherlands); Stoker, Jaap, E-mail: j.stoker@amc.uva.nl [Department of Radiology, Academic Medical Center, University of Amsterdam, PB 22660, 1100 DD Amsterdam (Netherlands)

    2013-08-15

    This article reviews two important aspects of CT-colonography, namely colonic distension and scan parameters. Adequate distension should be obtained to visualize the complete colonic lumen and optimal scan parameters should be used to prevent unnecessary radiation burden. For optimal distension, automatic carbon dioxide insufflation should be performed, preferably via a thin, flexible catheter. Hyoscine butylbromide is – when available – the preferred spasmolytic agent because of the positive effect on insufflation and pain/burden and its low costs. Scans in two positions are required for adequate distension and high polyp sensitivity and decubitus position may be used as an alternative for patients unable to lie in prone position. The great intrinsic contrast between air or tagging and polyps allows the use of low radiation dose. Low-dose protocol without intravenous contrast should be used when extracolonic findings are deemed unimportant. In patients suspected for colorectal cancer, normal abdominal CT scan protocols and intravenous contrast should be used in supine position for the evaluation of extracolonic findings. Dose reduction can be obtained by lowering the tube current and/or voltage. Tube current modulation reduces the radiation dose (except in obese patients), and should be used when available. Iterative reconstructions is a promising dose reducing tool and dual-energy CT is currently evaluated for its applications in CT-colonography. This review also provides our institution's insufflation procedure and scan parameters.

  20. Role of multiphase scans by multirow-detector helical CT in detecting small hepatocellular carcinoma

    Institute of Scientific and Technical Information of China (English)

    Hong Zhao; Kang-Rong Zhou; Fu-Hua Yan

    2003-01-01

    AIM: To evaluate the role of multiphasic scanning by multirow-detector helical CT (MDCT) in detecing small hypervascular hepatocellular carcinoma (SHCC).METHODS: Multiphasic scanning was carried out in 75patients with SHCC with Marconi MX8000 CT scanner. The early arterial phase (EAP), late arterial phase (LAP) and the portal venous phase (PVP) scans were started at 21 s, 34 s and 85 s respectively. The mean difference of CT values between tumor and liver parenchyma for each scanning phase was measured, and the sensitivity of detection of SHCC in each of these phases and in the combined phase was calculated and statistically analyzed.RESULTS: The mean difference of CT values between tumor and liver parenchyma was significant in 71 lesions≥1 cm in three phases (P<0.05). In 91 tumor foci, the detectability of SHCC was 45.1%, 83.5% and 92.3% in EAP, LAP and double arterial phases (DAP), respectively. The early arterial phase plus the portal venous phase and the double arterial phase plus the portal venous phase were 94.5%, 97.8%,respectively. Whereas the detectability in LAP plus PVP and in DAP plus PVP had no statistical difference.CONCLUSION: The utility of faster speed and thinner slice MDCT and multiphase scanning protocol can improve the detectability of hypervascular small hepatocellular carcinoma.Among which LAP is superior to EAP in depicting the lesions.

  1. A comparative study of whole body DWIBS MRI versus bone scan for evaluating skeletal metastases

    Directory of Open Access Journals (Sweden)

    SG Gandage

    2012-12-01

    Full Text Available BackgroundSkeletal metastases in oncology patients are identified by Bone scan and/Positron Emission Tomography (PET scan. But developing countries in the world still lack adequate numbers of these imaging facilities.AimsSince Magnetic Resonance Imaging (MRI is widely available as compared to bone scan or PET scan; a double blind study was undertaken to see if whole body imaging with MRI can give an idea of skeletal metastases.MethodDiffusion weighted whole body Magnetic Resonance Imaging with background body signal suppression (DWIBS was performed using 1.5 Tesla (T MRI on histopathologically proven cases of carcinoma of breast within two months of mastectomy and followed up after a year of surgery. Similarly bone scan was also performed in these patients.ResultsDWIBS MRI demonstrated the presence and extent of bone metastases in 10 out of a total 18 patients included in study while bone scan could demonstrate them in only three cases. A highly significant difference between proportions of the skeletal metastases detected by whole body DWIBS-MRI than that by bone scan at one year follow-up. (i.e. p<0.01, z=2.66 was seen.ConclusionDWIBS MRI scores high in demonstrating skeletal metastases. Further comparative studies are necessary to evaluate if DWIBS can replace bone scan or PET scan.

  2. Accuracy of trabecular bone microstructural measurement at planned dental implant sites using cone-beam CT datasets

    NARCIS (Netherlands)

    N. Ibrahim; A. Parsa; B. Hassan; P. van der Stelt; I.H.A. Aartman; D. Wismeijer

    2014-01-01

    Objective Cone-beam CT (CBCT) images are infrequently utilized for trabecular bone microstructural measurement due to the system's limited resolution. The aim of this study was to determine the accuracy of CBCT for measuring trabecular bone microstructure in comparison with micro CTCT). Materials

  3. Normalization of CT scans reconstructed with different kernels to reduce variability in emphysema measurements

    Science.gov (United States)

    Gallardo Estrella, L.; van Ginneken, B.; van Rikxoort, E. M.

    2013-03-01

    Chronic Obstructive Pulmonary Disease (COPD) is a lung disease characterized by progressive air flow limitation caused by emphysema and chronic bronchitis. Emphysema is quantified from chest computed tomography (CT) scans as the percentage of attentuation values below a fixed threshold. The emphysema quantification varies substantially between scans reconstructed with different kernels, limiting the possibilities to compare emphysema quantifications obtained from scans with different reconstruction parameters. In this paper we propose a method to normalize scans reconstructed with different kernels to have the same characteristics as scans reconstructed with a reference kernel and investigate if this normalization reduces the variability in emphysema quantification. The proposed normalization splits a CT scan into different frequency bands based on hierarchical unsharp masking. Normalization is performed by changing the energy in each frequency band to the average energy in each band in the reference kernel. A database of 15 subjects with COPD was constructed for this study. All subjects were scanned at total lung capacity and the scans were reconstructed with four different reconstruction kernels. The normalization was applied to all scans. Emphysema quantification was performed before and after normalization. It is shown that the emphysema score varies substantially before normalization but the variation diminishes after normalization.

  4. Dose reduction for CT in children with cystic fibrosis: is it feasible to reduce the number of images per scan?

    International Nuclear Information System (INIS)

    Reducing the dose for each CT scan is important for children with cystic fibrosis (CF). To determine whether the number of CT images and therefore the dose per CT scan could be reduced without any significant loss of information in children with CF. A cohort of children with CF was followed with biennial surveillance CT scans, obtained in inspiration after a voluntary breath-hold as 1-mm thick images at 10-mm intervals from lung apex to base. A random set of 20 baseline CT scans and 10 follow-up CT scans were blinded. Sets of every image (10-mm intervals), every second image (20-mm intervals), every third image (30-mm intervals) and a selection of three and five images were scored randomly using a published CT scoring system by one experienced observer. The 20 subjects were 10 years of age with a range of 3.7-17.6 years at baseline. Fewer CT images resulted in a significantly lower (less abnormal) CT score and the number of patients positive for abnormalities decreased subsequently. At intervals greater than 20 mm no significant change in CT score over 2 years could be detected, while the CT scores at 10-mm (P=0.02) and 20-mm (P=0.02) intervals worsened significantly. A reduction in the number of inspiratory CT images by increasing the interval between images to greater than 10 mm is not a valid option for radiation dose reduction in children with CF. (orig.)

  5. Isotope bone scans in the assessment of children with hip pain or limp

    International Nuclear Information System (INIS)

    Bone scans from 43 children referred with hip pain of uncertain cause were reviewed. The bone scan was abnormal in 36 patients: normal in 7. In 12 the findings were diagnostic: osteomyelitis, osteoid osteoma, osteomyelitis with septic arthritis, Perthes' Disease and juvenile chronic arthritis. Twenty-four patients had abnormal scans including diffuse periarticular increase and of these 18 had transient synovitis. Immobilisation and trauma accounted for the remainder. Isotope bone scans have been found to be a valuable investigation in children presenting with hip pain or limp, where the X-rays may appear normal or nondiagnostic. (orig.)

  6. "Bottle Brush Sign"-Spinal Meningeal Disease on 18F-FDG PET-CT Scan.

    Science.gov (United States)

    Riaz, Saima; Naz, Fozia; Bashir, Humayun; Niazi, Imran Khalid

    2016-09-01

    A 30-year-old man with a history of stage IV AE diffuse large cell lymphoma of left proximal humerus presented with new onset lower limb weakness at completion of chemotherapy. The F-FDG PET-CT scan showed increased intraspinal uptake from T12 to S1 vertebrae with unique "bottle brush" appearance in keeping with spinal meningeal disease. The leptomeningeal disease was further confirmed on correlative MRI scan. PMID:27405033

  7. Interactive lung segmentation in abnormal human and animal chest CT scans

    Energy Technology Data Exchange (ETDEWEB)

    Kockelkorn, Thessa T. J. P., E-mail: thessa@isi.uu.nl; Viergever, Max A. [Image Sciences Institute, University Medical Center Utrecht, 3584 CX Utrecht (Netherlands); Schaefer-Prokop, Cornelia M. [Department of Radiology, Meander Medical Centre, 3813 TZ Amersfoort, The Netherlands and Diagnostic Image Analysis Group, Radboud University Nijmegen Medical Centre, 6525 GA Nijmegen (Netherlands); Bozovic, Gracijela [Center for Diagnostic Imaging and Physiology, Skåne University Hospital, Lund University, SE-221 85 Lund (Sweden); Muñoz-Barrutia, Arrate [Cancer Imaging Laboratory, Center for Applied Medical Research, University of Navarra, ES-31008 Pamplona, Navarra (Spain); Rikxoort, Eva M. van [Diagnostic Image Analysis Group, Radboud University Nijmegen Medical Centre, 6525 GA Nijmegen (Netherlands); Brown, Matthew S. [Center for Computer Vision and Imaging Biomarkers, Department of Radiological Sciences, David Geffen School of Medicine at UCLA, University of California, Los Angeles, California 90024 (United States); Jong, Pim A. de [Department of Radiology, University Medical Center Utrecht, 3584 CX Utrecht (Netherlands); Ginneken, Bram van [Diagnostic Image Analysis Group, Radboud University Nijmegen Medical Centre, 6525 GA Nijmegen (Netherlands); Image Sciences Institute, University Medical Center Utrecht, 3584 CX Utrecht (Netherlands)

    2014-08-15

    Purpose: Many medical image analysis systems require segmentation of the structures of interest as a first step. For scans with gross pathology, automatic segmentation methods may fail. The authors’ aim is to develop a versatile, fast, and reliable interactive system to segment anatomical structures. In this study, this system was used for segmenting lungs in challenging thoracic computed tomography (CT) scans. Methods: In volumetric thoracic CT scans, the chest is segmented and divided into 3D volumes of interest (VOIs), containing voxels with similar densities. These VOIs are automatically labeled as either lung tissue or nonlung tissue. The automatic labeling results can be corrected using an interactive or a supervised interactive approach. When using the supervised interactive system, the user is shown the classification results per slice, whereupon he/she can adjust incorrect labels. The system is retrained continuously, taking the corrections and approvals of the user into account. In this way, the system learns to make a better distinction between lung tissue and nonlung tissue. When using the interactive framework without supervised learning, the user corrects all incorrectly labeled VOIs manually. Both interactive segmentation tools were tested on 32 volumetric CT scans of pigs, mice and humans, containing pulmonary abnormalities. Results: On average, supervised interactive lung segmentation took under 9 min of user interaction. Algorithm computing time was 2 min on average, but can easily be reduced. On average, 2.0% of all VOIs in a scan had to be relabeled. Lung segmentation using the interactive segmentation method took on average 13 min and involved relabeling 3.0% of all VOIs on average. The resulting segmentations correspond well to manual delineations of eight axial slices per scan, with an average Dice similarity coefficient of 0.933. Conclusions: The authors have developed two fast and reliable methods for interactive lung segmentation in

  8. Exogenous lipoid pneumonia with unusual CT pattern and FDG positron emission tomography scan findings

    International Nuclear Information System (INIS)

    We report a case of an exogenous lipoid pneumonia that appeared as a spiculated calcified mass on CT scan in which a positron emission tomography (PET) scan was performed before histological analysis. The F-18 fluoro-deoxy-D-glucose (FDG) PET showed a pattern highly suggestive of malignancy which, to our knowledge, has not yet been described. Similar to inflammatory and infectious lung diseases, lipoid pneumonia may be a false-positive case of F-18 FDG uptake. (orig.)

  9. ScanSim: A tool for simulating optical-CT imaging

    OpenAIRE

    Oldham, Mark

    2010-01-01

    A software tool has been developed that can simulate image formation in a variety of optical-CT scanning configurations. The formalism of the simulation is introduced, including two main modes: a diverging point source mode, and a converging broad beam mode. Preliminary results are presented for scanning Presage dosimeters in both modes and immersed in refractive media of widely varying refractive index (RI), including air, water, and a fully matched medium. Pronounced differences in the edge...

  10. Exogenous lipoid pneumonia with unusual CT pattern and FDG positron emission tomography scan findings

    Energy Technology Data Exchange (ETDEWEB)

    Tahon, Florence; Berthezene, Yves; Blineau, Nadine; Marchand, Bruno [Department of Radiology, Hopital de la Croix-Rousse, 103 grande rue de la Croix-Rousse, 69317 Lyon Cedex (France); Hominal, Stephane; Guerin, Jean-Claude [Department of Chest, Hopital de la Croix-Rousse, 103 grande rue de la Croix-Rousse, 69317 Lyon Cedex (France); Cinotti, Luc [CERMEP, 59 bd Pinel, 69003 Lyon Cedex (France)

    2002-07-01

    We report a case of an exogenous lipoid pneumonia that appeared as a spiculated calcified mass on CT scan in which a positron emission tomography (PET) scan was performed before histological analysis. The F-18 fluoro-deoxy-D-glucose (FDG) PET showed a pattern highly suggestive of malignancy which, to our knowledge, has not yet been described. Similar to inflammatory and infectious lung diseases, lipoid pneumonia may be a false-positive case of F-18 FDG uptake. (orig.)

  11. Interactive lung segmentation in abnormal human and animal chest CT scans

    International Nuclear Information System (INIS)

    Purpose: Many medical image analysis systems require segmentation of the structures of interest as a first step. For scans with gross pathology, automatic segmentation methods may fail. The authors’ aim is to develop a versatile, fast, and reliable interactive system to segment anatomical structures. In this study, this system was used for segmenting lungs in challenging thoracic computed tomography (CT) scans. Methods: In volumetric thoracic CT scans, the chest is segmented and divided into 3D volumes of interest (VOIs), containing voxels with similar densities. These VOIs are automatically labeled as either lung tissue or nonlung tissue. The automatic labeling results can be corrected using an interactive or a supervised interactive approach. When using the supervised interactive system, the user is shown the classification results per slice, whereupon he/she can adjust incorrect labels. The system is retrained continuously, taking the corrections and approvals of the user into account. In this way, the system learns to make a better distinction between lung tissue and nonlung tissue. When using the interactive framework without supervised learning, the user corrects all incorrectly labeled VOIs manually. Both interactive segmentation tools were tested on 32 volumetric CT scans of pigs, mice and humans, containing pulmonary abnormalities. Results: On average, supervised interactive lung segmentation took under 9 min of user interaction. Algorithm computing time was 2 min on average, but can easily be reduced. On average, 2.0% of all VOIs in a scan had to be relabeled. Lung segmentation using the interactive segmentation method took on average 13 min and involved relabeling 3.0% of all VOIs on average. The resulting segmentations correspond well to manual delineations of eight axial slices per scan, with an average Dice similarity coefficient of 0.933. Conclusions: The authors have developed two fast and reliable methods for interactive lung segmentation in

  12. Automatic coronary calcium scoring in low-dose non-ECG-synchronized thoracic CT scans

    Science.gov (United States)

    Isgum, Ivana; Prokop, Mathias; Jacobs, Peter C.; Gondrie, Martijn J.; Mali, Willem P. Th. M.; Viergever, Max A.; van Ginneken, Bram

    2010-03-01

    This work presents a system for automatic coronary calcium scoring and cardiovascular risk stratification in thoracic CT scans. Data was collected from a Dutch-Belgian lung cancer screening trial. In 121 low-dose, non-ECG synchronized, non-contrast enhanced thoracic CT scans an expert scored coronary calcifications manually. A key element of the proposed algorithm is that the approximate position of the coronary arteries was inferred with a probabilistic coronary calcium atlas. This atlas was created with atlas-based segmentation from 51 scans and their manually identified calcifications, and was registered to each unseen test scan. In the test scans all objects with density above 130 HU were considered candidates that could represent coronary calcifications. A statistical pattern recognition system was designed to classify these candidates using features that encode their spatial position relative to the inferred position of the coronaries obtained from the atlas registration. In addition, size and texture features were computed for all candidates. Two consecutive classifiers were used to label each candidate. The system was trained with 35 and tested with another 35 scans. The detected calcifications were quantified and cardiovascular risk was determined for each subject. The system detected 71% of coronary calcifications with an average of 0.9 false positive objects per scan. Cardiovascular risk category was correctly assigned to 29 out of 35 subjects (83%). Five scans (14%) were one category off, and only one scan (3%) was two categories off. We conclude that automatic assessment of the cardiovascular risk from low-dose, non-ECG synchronized thoracic CT scans appears feasible.

  13. Reduction scan time pitch for media measurement procedures ITV in lung cancer with CT-CT fusion; Reduccion de pitch para scantime medios en procedimientos de medida de ITV en cancer de pulmon con fusion CT-CT

    Energy Technology Data Exchange (ETDEWEB)

    Velazquez Miranda, S.; Ramirez Gutierrez, Y.; Rodriguez Alarcon, C.; Herrador Cordoba, M.

    2011-07-01

    The evolution of CT technology has led to the non-specific scanners for radiotherapy the scan time maximum is reduced to 2 seconds. This forces us to change the procedure for obtaining similar results.

  14. Clinical implication of F-18 FDG PET/CT for differentiated thyroid cancer in patients with negative diagnostic iodine-123 scan and elevated thyroglobulin

    International Nuclear Information System (INIS)

    This study aims to investigate the usefulness of F-18 FDG PET/CT in differentiated thyroid cancer (DTC) with elevated serum thyroglobulin (Tg) but negative iodine-123 (I-123) scan. Methods: Twenty patients with histopathologically proven DTC, negative diagnostic I-123 scan, and elevated serum Tg levels were prospectively submitted to F-18 FDG PET/CT evaluation. The histopathologic findings consisted of 19 papillary thyroid cancers, 1 follicular thyroid cancer. Results: F-18 FDG PET/CT identified lesions in 18 out of 20 patients, giving a sensitivity of 90%. Thirteen of the 18 patients revealed limited loco-regional disease. Remaining 5 patients showed distant metastases, consisting of 4 patients with lung metastases and 1 patient with bone metastasis. Two patients revealed negative F-18 FDG PET/CT findings. Conclusion: F-18 FDG PET/CT is suitable for the detection and precise localization of loco-regional recurrences and distant metastases of DTC in patients with elevated serum Tg but negative I-123 whole body scan.

  15. Preoperative assessment of the cancellous bone mineral density of the proximal humerus using CT data

    Energy Technology Data Exchange (ETDEWEB)

    Krappinger, Dietmar; Roth, Tobias; Gschwentner, Martin; Suckert, Armin; Blauth, Michael; Hengg, Clemens; Kralinger, Franz [Innsbruck Medical University, Department of Trauma Surgery and Sports Medicine, Innsbruck (Austria)

    2012-03-15

    Osteoporotic fractures of the proximal humerus show an increasing incidence. Osteoporosis not only influences the fracture risk after low-energy trauma, but also affects the mechanical stability of internal fixation. Preoperative assessment of the local bone quality may be useful in the surgical treatment of patients sustaining these injuries. The aim of the present study was to present a method for the preoperative assessment of the local cancellous bone mineral density (BMD) of the proximal humerus using CT data. In the first part of the study, CT scans of 30 patients with unilateral fractures of the proximal humerus after low-energy trauma were used. The local BMD was assessed on the contralateral uninjured side. All 30 patients additionally underwent dual-emission X-ray absorptiometry (DXA) of the lumbar spine, proximal femur, and forearm of the side of the uninjured proximal humerus within 6 weeks after trauma. Three independent trauma surgeons performed measurements on the uninjured proximal humerus twice with a time interval of 4 weeks in order to assess the inter- and intraobserver reliability of the method. In the second part of the study, the local BMD of 507 patients with either proximal humerus fractures or chronic shoulder instability was assessed by a single trauma surgeon. In both parts, the average HU values in standardized ROIs of the humeral head were automatically calculated after correcting for HU values below the water equivalent. A linear calibration equation was computed for the calculation from HU to BMD using a calibration device (EFP). The intra- and interobserver reliability was high (ICC > 0.95). Correlation coefficients between the local BMD of the proximal humerus and other anatomical sites were between 0.35 (lumbar spine) and 0.64 (forearm). We found a high correlation between the local BMD and age. The BMD in the fracture group was significantly lower than in the instability group. These patients were significantly older and more

  16. Value and limits of μ-CT for nondemineralized bone tissue processing.

    Science.gov (United States)

    Draenert, Miriam Esther; Draenert, Alice Irène; Forriol, Francisco; Cerler, Michael; Kunzelmann, Karl-Heinz; Hickel, Reinhard; Draenert, Klaus

    2012-04-01

    An experimental approach was performed on 20 giant rabbits to establish the possibilities and limitations of μ-CT for routine processing of nondemineralized bone tissue. Hydroxyapatite (HA) or β-tricalciumphosphate (β-TCP) bead implants or a melange of both, microchambered and solid, were implanted into a standardized and precise defect in the patellar groove. The bone-healing phase was chosen for the histology considering 1 or 2 days, and 2, 3, and 6 weeks. Normal X-ray and μ-CT were applied on all specimens; five specimens in the 6-week stage were additionally processed according to the full range of conventional nondemineralized bone processing methods. μ-CT increased the possibilities of nondemineralized histology with respect to bone morphometry and a complete sequence of sections, thus providing a complete analysis of the bone response. μ-CT was limited in differentiating bone quality, cell analyses, and mineralization stages. The investigation based on normal X-rays is limited to defining integration and excluding the fibrous and bony encapsulation of loose implants. μ-CT allows a 3D evaluation of newly formed bone which is clearly marked against the ceramic implant. It does not allow, however, for the differentiation between woven and lamellar bone, the presentation of the canalicular lacunar system, or on the cell level, revealing canaliculi or details of the mineralization process which can be documented by high-resolution microradiography. Titer dynamics of bone formation remains the domain of polychromatic sequential labeling. The complete sequence of μ-CT slices enhances the possibilities for routine histology, tremendously allowing to the focus on detail histology to topographically well-defined cuts, thus providing more precise conclusions which take into consideration the whole implant.

  17. Multienergy CT acquisition and reconstruction with a stepped tube potential scan

    Energy Technology Data Exchange (ETDEWEB)

    Shen, Le; Xing, Yuxiang, E-mail: xingyx@mail.tsinghua.edu.cn [Key Laboratory of Particle and Radiation Imaging (Tsinghua University), Ministry of Education and the Department of Engineering Physics, Tsinghua University, Beijing 100084 (China)

    2015-01-15

    Purpose: Based on an energy-dependent property of matter, one may obtain a pseudomonochromatic attenuation map, a material composition image, an electron-density distribution, and an atomic number image using a dual- or multienergy computed tomography (CT) scan. Dual- and multienergy CT scans broaden the potential of x-ray CT imaging. The development of such systems is very useful in both medical and industrial investigations. In this paper, the authors propose a new dual- and multienergy CT system design (segmental multienergy CT, SegMECT) using an innovative scanning scheme that is conveniently implemented on a conventional single-energy CT system. The two-step-energy dual-energy CT can be regarded as a special case of SegMECT. A special reconstruction method is proposed to support SegMECT. Methods: In their SegMECT, a circular trajectory in a CT scan is angularly divided into several arcs. The x-ray source is set to a different tube voltage for each arc of the trajectory. Thus, the authors only need to make a few step changes to the x-ray energy during the scan to complete a multienergy data acquisition. With such a data set, the image reconstruction might suffer from severe limited-angle artifacts if using conventional reconstruction methods. To solve the problem, they present a new prior-image-based reconstruction technique using a total variance norm of a quotient image constraint. On the one hand, the prior extracts structural information from all of the projection data. On the other hand, the effect from a possibly imprecise intensity level of the prior can be mitigated by minimizing the total variance of a quotient image. Results: The authors present a new scheme for a SegMECT configuration and establish a reconstruction method for such a system. Both numerical simulation and a practical phantom experiment are conducted to validate the proposed reconstruction method and the effectiveness of the system design. The results demonstrate that the proposed Seg

  18. Investigation of the potential causes of partial scan artifacts in dynamic CT myocardial perfusion imaging

    Science.gov (United States)

    Tao, Yinghua; Speidel, Michael; Szczykutowicz, Timothy; Chen, Guang-Hong

    2014-03-01

    In recent years, there have been several findings regarding CT number variations (partial scan artifact or PSA) across time in dynamic myocardial perfusion studies with short scan gated reconstruction. These variations are correlated with the view angle range corresponding to the short scan acquisition for a given cardiac phase, which can vary from one cardiac cycle to another due to the asynchrony between heart rate and gantry rotation speed. In this study, we investigate several potential causes of PSA, including noise, beam hardening and scatter, using numerical simulations. In addition, we investigate partial scan artifact in a single source 64-slice diagnostic CT scanner in vivo data sets, and report its effect on perfusion analysis. Results indicated that among all three factors investigated, scatter can cause obvious partial scan artifact in dynamic myocardial perfusion imaging. Further, scatter is a low frequency phenomenon and is not heavily dependent on the changing contrasts, as both the frequency method and the virtual scan method are effective in reducing partial scan artifact. However, PSA does not necessarily lead to different blood volume maps compared to the full scan, because these maps are usually generated with a curve fitting procedure.

  19. CT scan and US evaluation of the traumatic duodenal intramural hematoma in childhood

    International Nuclear Information System (INIS)

    CT scan and ultrasonography were very effective in evaluating and following-up the traumatic duodenal intramural hematoma in a child (5-year-old boy). These two methods were demonstrated very useful not only for ditection of associated trauma but also for diagnosis and follow-up of the duodenal intramural hematoma. (author)

  20. The fissural complex of the lung: anatomy and variations on thin-section CT scans

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Kyung Soo; Kim, Pyo Nyun; Kim, Il Young; Bae, Won Kyung; Lee, Byoung Ho [College of Medicine, Soonchunhyang University, Cheonan (Korea, Republic of)

    1994-03-15

    To evaluate further the right minor and major fissure on thin-section narrow-interval CT scans with particular emphases on orientation, degree of completeness. This section CT scans from 10 mm distal to carina to the proximal basal segmental bronchus were obtained at 5 mm invervals in 50 consecutive subjects. Orientation, degree of completeness, and the relationship of the minor and major fissure on thin-section CT scans were analyzed. Four principal types of the minor fissure could be identified according to the highest point of the upper surface of the middle lobe. At bronchus intermedius level, the major fissure appeared with its medial end anterior to lateral end in 45 subjects. The minor fissure was complete in only 10 subjects (20%). Completely absent minor fissure was noted in four subjects (8%). The major fissure was incomplete in 17 subjects (34%) at bronchus intermedius level, the minor and major fissure intersected each other in only 27 subjects (54%). The highest point of intersection was variable. There are much more variations in the fissural complex in our study than in previous reports and these variations can be visualized well on thin-section CT scans.

  1. Measurement of mesothelioma on thoracic CT scans: A comparison of manual and computer-assisted techniques

    International Nuclear Information System (INIS)

    Our purpose in this study was to evaluate the variability of manual mesothelioma tumor thickness measurements in computed tomography (CT) scans and to assess the relative performance of six computerized measurement algorithms. The CT scans of 22 patients with malignant pleural mesothelioma were collected. In each scan, an initial observer identified up to three sites in each of three CT sections at which tumor thickness measurements were to be made. At each site, five observers manually measured tumor thickness through a computer interface. Three observers repeated these measurements during three separate sessions. Inter- and intra-observer variability in the manual measurement of tumor thickness was assessed. Six automated measurement algorithms were developed based on the geometric relationship between a specified measurement site and the automatically extracted lung regions. Computer-generated measurements were compared with manual measurements. The tumor thickness measurements of different observers were highly correlated (r≥0.99); however, the 95% limits of agreement for relative inter-observer difference spanned a range of 30%. Tumor thickness measurements generated by the computer algorithms also correlated highly with the average of observer measurements (r≥0.93). We have developed computerized techniques for the measurement of mesothelioma tumor thickness in CT scans. These techniques achieved varying levels of agreement with measurements made by human observers

  2. Matching PET and CT scans of the head and neck area : Development of method and validation

    NARCIS (Netherlands)

    Klabbers, BM; de Munck, JC; Slotman, BJ; Langendijk, HA; de Bree, R; Hoekstra, OS; Boellaard, R; Lammertsma, AA

    2002-01-01

    Positron emission tomography (PET) provides important information on tumor biology, but lacks detailed anatomical information. Our aim in the present study was to develop and validate an automatic registration method for matching PET and CT scans of the head and neck. Three difficulties in achieving

  3. Study Finds Small Increase in Cancer Risk after Childhood CT Scans

    Science.gov (United States)

    A study published in the June 6, 2012, issue of The Lancet shows that radiation exposure from computed tomography (CT) scans in childhood results in very small but increased risks of leukemia and brain tumors in the first decade after exposure.

  4. Influence of cone beam CT scanning parameters on grey value measurements at an implant site

    NARCIS (Netherlands)

    A. Parsa; N. Ibrahim; B. Hassan; A. Motroni; P. van der Stelt; D. Wismeijer

    2013-01-01

    Objectives: The aim of this study was to determine the grey value variation at the implant site with different scan settings, including field of view (FOV), spatial resolution, number of projections, exposure time and dose selections in two cone beam CT (CBCT) systems and to compare the results with

  5. Body Tumor CT Perfusion Protocols: Optimization of Acquisition Scan Parameters in a Rat Tumor Model

    OpenAIRE

    Tognolini, Alessia; Schor-Bardach, Rachel; Pianykh, Oleg S.; Wilcox, Carol J.; Raptopoulos, Vassilios; Goldberg, S. Nahum

    2009-01-01

    Purpose: To evaluate the effects of total scanning time (TST), interscan delay (ISD), inclusion of image at peak vascular enhancement (IPVE), and selection of the input function vessel on the accuracy of tumor blood flow (BF) calculation with computed tomography (CT) in an animal model.

  6. Implant planning and placement using optical scanning and cone beam CT technology

    NARCIS (Netherlands)

    J.M. van der Zel

    2008-01-01

    There is a growing interest in minimally invasive implant therapy as a standard prosthodontic treatment, providing complete restoration of occlusal function. A new treatment method (CADDIMA), which combines both computerized tomographic (CT) and optical laser-scan data for planning and design of sur

  7. Automatic intrinsic cardiac and respiratory gating from cone-beam CT scans of the thorax region

    Science.gov (United States)

    Hahn, Andreas; Sauppe, Sebastian; Lell, Michael; Kachelrieß, Marc

    2016-03-01

    We present a new algorithm that allows for raw data-based automated cardiac and respiratory intrinsic gating in cone-beam CT scans. It can be summarized in three steps: First, a median filter is applied to an initially reconstructed volume. The forward projection of this volume contains less motion information and is subtracted from the original projections. This results in new raw data that contain only moving and not static anatomy like bones, that would otherwise impede the cardiac or respiratory signal acquisition. All further steps are applied to these modified raw data. Second, the raw data are cropped to a region of interest (ROI). The ROI in the raw data is determined by the forward projection of a binary volume of interest (VOI) that includes the diaphragm for respiratory gating and most of the edge of the heart for cardiac gating. Third, the mean gray value in this ROI is calculated for every projection and the respiratory/cardiac signal is acquired using a bandpass filter. Steps two and three are carried out simultaneously for 64 or 1440 overlapping VOI inside the body for the respiratory or cardiac signal respectively. The signals acquired from each ROI are compared and the most consistent one is chosen as the desired cardiac or respiratory motion signal. Consistency is assessed by the standard deviation of the time between two maxima. The robustness and efficiency of the method is evaluated using simulated and measured patient data by computing the standard deviation of the mean signal difference between the ground truth and the intrinsic signal.

  8. When to perform positron emission tomography/computed tomography or radionuclide bone scan in patients with recently diagnosed prostate cancer

    Directory of Open Access Journals (Sweden)

    Caldarella C

    2013-06-01

    Full Text Available Carmelo Caldarella,1 Giorgio Treglia,2 Alessandro Giordano,1 Luca Giovanella2 1Institute of Nuclear Medicine, Catholic University of the Sacred Heart, Rome, Italy; 2Department of Nuclear Medicine and PET/CT Centre, Oncology Institute of Southern Switzerland, Bellinzona, Switzerland Abstract: Skeletal metastases are very common in prostate cancer and represent the main metastatic site in about 80% of prostate cancer patients, with a significant impact in patients' prognosis. Early detection of bone metastases is critical in the management of patients with recently diagnosed high-risk prostate cancer: radical treatment is recommended in case of localized disease; systemic therapy should be preferred in patients with distant secondary disease. Bone scintigraphy using radiolabeled bisphosphonates is of great importance in the management of these patients; however, its main drawback is its low overall accuracy, due to the nonspecific uptake in sites of increased bone turnover. Positron-emitting radiopharmaceuticals, such as fluorine-18-fluorodeoxyglucose, choline-derived drugs (fluorine-18-fluorocholine and carbon-11-choline and sodium fluorine-18-fluoride, are increasingly used in clinical practice to detect metastatic spread, and particularly bone involvement, in patients with prostate cancer, to reinforce or substitute information provided by bone scan. Each radiopharmaceutical has a specific mechanism of uptake; therefore, diagnostic performances may differ from one radiopharmaceutical to another on the same lesions, as demonstrated in the literature, with variable sensitivity, specificity, and overall accuracy values in the same patients. Whether bone scintigraphy can be substituted by these new methods is a matter of debate. However, greater radiobiological burden, higher costs, and the necessity of an in-site cyclotron limit the use of these positron emission tomography methods as first-line investigations in patients with prostate cancer

  9. Repeated CT scan in improving the reproducibility of grass tumor volume for moving target

    International Nuclear Information System (INIS)

    Objective: To find a method to improve the range accuracy of moving target such as peripheral lung tumors, since a single CT snapshot may not be accurate during the treatment process.Methods: A simple harmonic motion phantom, embedded with a cube and a circular ball, was used to simulate the tumor motion. Individualized moving targets were scanned 24 times with different amplitudes and frequencies. Then the images were fused from every 1, 2 or 3 sets of CT scans. The GTV volume variation of circular target and the length variation of the cube target along the z axis were contoured and analyzed. Results: As motion amplitude increased, the maximum of both circular target volume and cube target length was increased, while the minimum of the factors was decreased. Motion frequency affected the target volume less than amplitude. For a cube target with the length of 3.3 cm at stationary phase, when motion frequencies was 20 and motion amplitude was 2 cm, the maximal length was 2. 4 times of the minimal length (5. 1 cm vs. 2. 1 cm). When it came to the cube target groups fused from every 1,2 and 3 sets of CT scans, the average length and standard deviation were (3.77 ± 1.20)cm, (4.18 ±0. 91)cm and (4.52 ±0. 59)cm, respectively. With the increase of fused scan number, targets became bigger, the standard deviation decreased, and the change of center positions was decreased. Conclusions: The motion amplitude, frequency and the number of CT scans are the main factors affecting target definition, though, the optimized scanning phase is not certained. When 4DCT and respiration gating technique are not available,the efficient and practical method to solve this problem is to scan the target three or more times and fuse them in planning system, which will generate a larger, more reproducible GTV volume for moving targets. (authors)

  10. Clinical value of CT scan in diagnosing nasal malignant lymphoma (a report of 11 cases)

    International Nuclear Information System (INIS)

    Objective: To investigate the value of CT in diagnosing nasal malignant lymphoma. Methods: CT findings of 11 patients with nasal malignant lymphoma proved pathologically were reviewed retrospectively. Results: The lesions pathologically diagnosed were all NHL and 9 cases were peripheral T-cell lymphoma. CT scan showed: (1) Lesions arose mainly from nasal vestibule or anterior part of nasal cavity, consisting of hyperplasia type 2 cases, infiltration type 3 cases, and hyperplasia-infiltration (mixed) type 6 cases. (2) Density of mass of hyperplasia type was relatively homogeneous, presenting as isodensity or slight hyper-density, while infiltration and mixed type appeared inhomogeneous. (3) Slight bony erosion was found in 8 cases, characterized by 'mouse nibbled' or cribriform bony absorption. (4) Adjacent structures were usually involved, and lesions might be polycentric. (5) Lesions often shrank or disappeared after radiotherapy. Conclusion: CT findings of nasal malignant lymphoma are relatively characteristic. It can clearly demonstrate the extent of lesion

  11. Virtual planning of dental implant placement using CT double scan-technique - own experience

    International Nuclear Information System (INIS)

    The correctness of CT performed with the use of a double-scan technique is the basis for achieving proper quality of 3D reconstructions of the maxilla or mandible and subsequent virtual planning of dental implant placement. The aim of this study was the presentation of the methodology of computed tomography scanning and own experience with the use of the double-scan technique. The study group included 26 individuals who underwent MDCT with a double-scan technique using a MDCT scanner SOMATOM Sensation (Siemens, Germany). The parameters of the examination: slice-collimation 10 x 0.75 mm, slice-thickness 0.75 mm. The first CT scan in the procedure was the scan of the patient wearing a radiological prosthesis and occlusal index, which was followed by a separate scan of the radiological prosthesis. These two CT scans were copied and transferred to PC with Procera Software program (Nobel Biocare, Sweden) where dental implant placement was virtually planned. In all 26 patients, precise three-dimensional reconstructions of the anatomical structure were obtained. In 11 patients, on the basis of the virtual planning, the implant placement was performed, 5 patients were referred to preparatory procedures, that is, restoration of the alveolar process, otolaryngological treatment of the maxillary sinuses. The remaining 10 patients did not qualify to the procedure because of unfavorable anatomical ideation's. Correct computed tomography with double-scan technique enables virtual planning of dental implant placement, on the basis of which the real procedure of implantation can be performed. (author)

  12. "High-precision, reconstructed 3D model" of skull scanned by conebeam CT: Reproducibility verified using CAD/CAM data.

    Science.gov (United States)

    Katsumura, Seiko; Sato, Keita; Ikawa, Tomoko; Yamamura, Keiko; Ando, Eriko; Shigeta, Yuko; Ogawa, Takumi

    2016-01-01

    Computed tomography (CT) scanning has recently been introduced into forensic medicine and dentistry. However, the presence of metal restorations in the dentition can adversely affect the quality of three-dimensional reconstruction from CT scans. In this study, we aimed to evaluate the reproducibility of a "high-precision, reconstructed 3D model" obtained from a conebeam CT scan of dentition, a method that might be particularly helpful in forensic medicine. We took conebeam CT and helical CT images of three dry skulls marked with 47 measuring points; reconstructed three-dimensional images; and measured the distances between the points in the 3D images with a computer-aided design/computer-aided manufacturing (CAD/CAM) marker. We found that in comparison with the helical CT, conebeam CT is capable of reproducing measurements closer to those obtained from the actual samples. In conclusion, our study indicated that the image-reproduction from a conebeam CT scan was more accurate than that from a helical CT scan. Furthermore, the "high-precision reconstructed 3D model" facilitates reliable visualization of full-sized oral and maxillofacial regions in both helical and conebeam CT scans. PMID:26832374

  13. Analysis on the reasons for diffuse 18F-FDG uptake by bone marrow using whole-body PET/CT

    International Nuclear Information System (INIS)

    Objective: To analyze the causes for diffuse bone marrow uptake of 18F-FDG on PET/CT scans. Methods: Sixty-six patients with diffuse bone marrow uptake on whole-body FDG-PET/CT imaging were enrolled for this study. Seventy-nine healthy subjects (with no history of tumor or recent fever) were selected as normal control. The SUVmax and SUVmean were measured in bone marrow and mediastinum in both groups. The maximum (bone marrow SUVmax/ mediastinum SUVmax) and mean value ratios (bone marrow SUVmean/ mediastinum SUVmean) were calculated. Statistical analysis was performed by one-factor variance analysis. Results: With diffuse bone marrow uptake pattern of 18F-FDG, 27 were caused by injection of hematopoietic growth factor, 21 by hematopathy and 18 due to fever. SUVmean of those three causes were 3.076±1.955, 3.633±2.405 and 2.546±0.791 respectively, each was significantly different from that of the control group (1.026±0.190; F=34.465, P<0.001). Conclusion: Diffuse bone marrow uptake on FDG-PET/CT are caused by both benign and malignant reasons. (authors)

  14. Self-guided clinical cases for medical students based on postmortem CT scans of cadavers.

    Science.gov (United States)

    Bohl, Michael; Francois, Webster; Gest, Thomas

    2011-07-01

    In the summer of 2009, we began full body computed tomography (CT) scanning of the pre-embalmed cadavers in the University of Michigan Medical School (UMMS) dissection lab. We theorized that implementing web-based, self-guided clinical cases based on postmortem CT (PMCT) scans would result in increased student appreciation for the clinical relevance of anatomy, increased knowledge of cross-sectional anatomy, and increased ability to identify common pathologies on CT scans. The PMCT scan of each cadaver was produced as a DICOM dataset, and then converted into a Quicktime movie file using Osirix software. Clinical cases were researched and written by the authors, and consist of at least one Quicktime movie of a PMCT scan surrounded by a novel navigation interface. To assess the value of these clinical cases we surveyed medical students at UMMS who are currently using the clinical cases in their coursework. Students felt the clinical cases increased the clinical relevance of anatomy (mean response 7.77/10), increased their confidence finding anatomical structures on CT (7.00/10), and increased their confidence recognizing common pathologies on CT (6.17/10). Students also felt these clinical cases helped them synthesize material from numerous courses into an overall picture of a given disease process (7.01/10). These results support the conclusion that our clinical cases help to show students why the anatomy they are learning is foundational to their other coursework. We would recommend the use of similar clinical cases to any medical school utilizing cadaver dissection as a primary teaching method in anatomy education.

  15. Bone metastasis in patients with non-small cell lung cancer: The diagnostic role of F-18 FDG PET/CT

    International Nuclear Information System (INIS)

    Purpose: To evaluate the performance of F-18 FDG PET/CT in the detection of bone metastasis in non-small cell lung cancer (NSCLC) patients. Materials and methods: Three hundred and sixty-two consecutive NSCLC patients who underwent F-18 FDG PET/CT scanning were retrospectively analyzed. Each image of PET/CT, combined CT, and PET was performed at 10 separate areas and interpreted blindly and separately. The sensitivity, specificity and accuracy of F-18 FDG PET/CT, combined CT and F-18 FDG PET were calculated and the results were statistically analyzed. Results: Bone metastasis was confirmed in 82 patients with 331 positive segments based on the image findings and clinical follow-up. On patient-based analysis, the sensitivity of F-18 FDG PET/CT (93.9%) was significantly higher than those of combined CT (74.4%) and F-18 FDG PET (84.1%), respectively (p < 0.05). The overall specificity and accuracy of combined CT, F-18 FDG PET, and F-18 FDG PET/CT were 90.7%, 93.2%, 98.9% and 87.0%, 91.2%, and 97.8%, respectively (compared with PET/CT, p < 0.05). On segment-based analysis, the sensitivity of the three modalities were 79.5%, 94.3%, and 98.8%, respectively (compared with PET/CT, p < 0.05). The overall specificity and accuracy of the three modalities were 87.9%, 89.2%, 98.6% and 84.5%, 91.2%, 98.7%, respectively (compared with PET/CT, p < 0.05). Conclusion: F-18 FDG PET/CT is superior to F-18 FDG PET or combined CT in detecting bone metastasis of NSCLC patients because of the complementation of CT and PET. It is worth noting that the added value of F-18 FDG PET/CT may beneficially impact the clinical management of NSCLC.

  16. Technetium phosphate bone scan in the diagnosis of septic arthritis in childhood

    Energy Technology Data Exchange (ETDEWEB)

    Sundberg, S.B.; Savage, J.P.; Foster, B.K. (Adelaide Childrens Hospital (Australia))

    1989-09-01

    The technetium phosphate bone scans of 106 children with suspected septic arthritis were reviewed to determine whether the bone scan can accurately differentiate septic from nonseptic arthropathy. Only 13% of children with proved septic arthritis had correct blind scan interpretation. The clinically adjusted interpretation did not identify septic arthritis in 30%. Septic arthritis was incorrectly identified in 32% of children with no evidence of septic arthritis. No statistically significant differences were noted between the scan findings in the septic and nonseptic groups and no scan findings correlated specifically with the presence or absence of joint sepsis.

  17. Preliminary results of automated removal of degenerative joint disease in bone scan lesion segmentation

    Science.gov (United States)

    Chu, Gregory H.; Lo, Pechin; Kim, Hyun J.; Auerbach, Martin; Goldin, Jonathan; Henkel, Keith; Banola, Ashley; Morris, Darren; Coy, Heidi; Brown, Matthew S.

    2013-03-01

    Whole-body bone scintigraphy (or bone scan) is a highly sensitive method for visualizing bone metastases and is the accepted standard imaging modality for detection of metastases and assessment of treatment outcomes. The development of a quantitative biomarker using computer-aided detection on bone scans for treatment response assessment may have a significant impact on the evaluation of novel oncologic drugs directed at bone metastases. One of the challenges to lesion segmentation on bone scans is the non-specificity of the radiotracer, manifesting as high activity related to non-malignant processes like degenerative joint disease, sinuses, kidneys, thyroid and bladder. In this paper, we developed an automated bone scan lesion segmentation method that implements intensity normalization, a two-threshold model, and automated detection and removal of areas consistent with non-malignant processes from the segmentation. The two-threshold model serves to account for outlier bone scans with elevated and diffuse intensity distributions. Parameters to remove degenerative joint disease were trained using a multi-start Nelder-Mead simplex optimization scheme. The segmentation reference standard was constructed manually by a panel of physicians. We compared the performance of the proposed method against a previously published method. The results of a two-fold cross validation show that the overlap ratio improved in 67.0% of scans, with an average improvement of 5.1% points.

  18. Anatomy-based registration of CT-scan and intraoperative X-ray images for guiding a surgical robot.

    Science.gov (United States)

    Guéziec, A; Kazanzides, P; Williamson, B; Taylor, R H

    1998-10-01

    We describe new methods for rigid registration of a preoperative computed tomography (CT)-scan image to a set of intraoperative X-ray fluoroscopic images, for guiding a surgical robot to its trajectory planned from CT. Our goal is to perform the registration, i.e., compute a rotation and translation of one data set with respect to the other to within a prescribed accuracy, based upon bony anatomy only, without external fiducial markers. With respect to previous approaches, the following aspects are new: 1) we correct the geometric distortion in fluoroscopic images and calibrate them directly with respect to the robot by affixing to it a new calibration device designed as a radiolucent rod with embedded metallic markers, and by moving the device along two planes, while radiographs are being acquired at regular intervals; 2) the registration uses an algorithm for computing the best transformation between a set of lines in three space, the (intraoperative) X-ray paths, and a set of points on the surface of the bone (imaged preoperatively), in a statistically robust fashion, using the Cayley parameterization of a rotation; and 3) to find corresponding sets of points to the X-ray paths on the surfaces, our new approach consists of extracting the surface apparent contours for a given viewpoint, as a set of closed three-dimensional nonplanar curves, before registering the apparent contours to X-ray paths. Aside from algorithms, there are a number of major technical difficulties associated with engineering a clinically viable system using anatomy and image-based registration. To detect and solve them, we have so far conducted two experiments with the surgical robot in an operating room (OR), using CT and fluoroscopic image data of a cadaver bone, and attempting to faithfully simulate clinical conditions. Such experiments indicate that intraoperative X-ray-based registration is a promising alternative to marker-based registration for clinical use with our proposed method.

  19. Combined bone scintigraphy and indium-111 leukocyte scans in neuropathic foot disease

    Energy Technology Data Exchange (ETDEWEB)

    Schauwecker, D.S.; Park, H.M.; Burt, R.W.; Mock, B.H.; Wellman, H.N.

    1988-10-01

    It is difficult to diagnose osteomyelitis in the presence of neurotrophic osteoarthropathy. We performed combined (99mTc)MDP bone scans and indium-111 (111In) leukocyte studies on 35 patients who had radiographic evidence of neuropathic foot disease and clinically suspected osteomyelitis. The (111In)leukocyte study determined if there was an infection and the bone scan provided the anatomic landmarks so that the infection could be localized to the bone or the adjacent soft tissue. Seventeen patients had osteomyelitis and all showed increased (111In)leukocyte activity localized to the bone, giving a sensitivity of 100%. Among the 18 patients without osteomyelitis, eight had no accumulation of (111In)leukocytes, seven had the (111In)leukocyte activity correctly localized to the soft tissue, two had (111In)leukocyte activity mistakenly attributed to the bone, and one had (111In)leukocyte accumulation in a proven neuroma which was mistakenly attributed to bone. These three false-positive results for osteomyelitis reduced the specificity to 83%. Considering only the 27 patients with a positive (111In)leukocyte study, the combined bone scan and (111In)leukocyte study correctly localized the infection to the soft tissues or bone in 89%. Uninfected neurotrophic osteoarthropathy does not accumulate (111In)leukocytes. We found the combined bone scan and (111In) leukocyte study useful for the detection and localization of infection to soft tissue or bone in patients with neuropathic foot disease.

  20. Dual-time-point FDG-PET/CT Imaging of Temporal Bone Chondroblastoma: A Report of Two Cases

    OpenAIRE

    Akira Toriihara; Atsunobu Tsunoda; Akira Takemoto; Kazunori Kubota; Youichi Machida; Ukihide Tateishi

    2015-01-01

    Temporal bone chondroblastoma is an extremely rare benign bone tumor. We encountered two cases showing similar imaging findings on computed tomography (CT), magnetic resonance imaging (MRI), and dual-time-point 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography (PET)/CT. In both cases, CT images revealed temporal bone defects and sclerotic changes around the tumor. Most parts of the tumor showed low signal intensity on T2- weighted MRI images and non-uniform enhancement on gadolini...

  1. Changes observed in radionuclide bone scans during and after teriparatide treatment for osteoporosis

    Energy Technology Data Exchange (ETDEWEB)

    Moore, Amelia E.B.; Blake, Glen M.; Fogelman, Ignac [King' s College London, School of Medicine, Department of Nuclear Medicine, London (United Kingdom); Taylor, Kathleen A.; Ruff, Valerie A.; Rana, Asad E.; Wan, Xiaohai [Eli Lilly and Company, Indianapolis, IN (United States)

    2012-02-15

    Visual changes on radionuclide bone scans have been reported with teriparatide treatment. To assess this, serial studies were evaluated and quantified in ten postmenopausal women with osteoporosis treated with teriparatide (20 {mu}g/day subcutaneous) who had {sup 99m}Tc-methylene diphosphonate (MDP) bone scans (baseline, 3 and 18 months, then after 6 months off therapy). Women were injected with 600 MBq {sup 99m}Tc-MDP, and diagnostic bone scan images were assessed at 3.5 h. Additional whole-body scans (10 min, 1, 2, 3 and 4 h) were analysed for {sup 99m}Tc-MDP skeletal plasma clearance (K{sub bone}). Regional K{sub bone} differences were obtained for the whole skeleton and six regions (calvarium, mandible, spine, pelvis, upper and lower extremities). Bone turnover markers (BTM) were also measured. Most subjects showed visual changes on 3- and 18-month bone scan images that disappeared after 6 months off therapy. Enhanced uptake was seen predominantly in the calvarium and lower extremities. Whole skeleton K{sub bone} displayed a median increase of 22% (3 months, p = 0.004) and 34% (18 months, p = 0.002) decreasing to 0.7% (6 months off therapy). Calvarium K{sub bone} changes were three times larger than other sites. After 6 months off therapy, all K{sub bone} and BTM values returned towards baseline. The increased {sup 99m}Tc-MDP skeletal uptake with teriparatide indicated increased bone formation which was supported by BTM increases. After 6 months off therapy, metabolic activity diminished towards baseline. The modulation of {sup 99m}Tc-MDP skeletal uptake during treatment was the result of teriparatide's metabolic activity. These findings may aid the radiological evaluation of similar teriparatide patients having radionuclide bone scans. (orig.)

  2. Application of dual-energy scanning technique with dual-source CT in pulmonary mass lesions

    International Nuclear Information System (INIS)

    Objective: To explore the feasibility of DSCT dual-energy technique in pulmonary mass lesions. Methods: A total of 100 patients with pulmonary masses underwent conventional plain CT scan and dual-energy enhanced CT scan. The virtual non-contrast (VNC) images were obtained at post-processing workstation.The mean CT value,enhancement value,signal to noise ratio (SNR), image quality and radiation dose of pulmonary masses were compared between the two scan techniques using F or t test and the detectability of lesions was compared using Wilcoxon test. Results: There was no statistically significant difference among VNC (A) (32.89 ± 12.58) HU,VNC (S) (30.86 ± 9.60) HU and conventional plain images (35.89 ± 9.99) HU in mean CT value of mass (F =2.08, P>0.05). There was statistically significant difference among VNC (A) (3.29 ± 1.45), VNC (S) (3.93 ± 1.49) and conventional plain image (4.61 ± 1.50) in SNR (F =6.01, P<0.05), which of conventional plain scan was higher than that of VNC.The enhancement value of mass in conventional enhanced scan (60.74 ± 13.9) HU and distribution of iodine from VNC (A) (58.26 ± 31.99) HU was no statistically significant difference (t=0.48, P>0.05), but there was a significant difference between conventional enhanced scan (56.51 ± 17.94) HU and distribution of iodine from VNC (S) (52.65 ± 16.78) HU (t=4.45, P<0.05). There was no statistically significant difference among conventional plain scan (4.69 ± 0.06) and VNC (A) (4.60 ± 0.09), VNC (S) (4.61 ±0.11) in image quality at mediastinal window (F=3.014, P>0.05). The appearance, size, internal features of mass (such as necrosis, calcification and cavity) were showed the same in conventional plain scan, VNC (A) and VNC (S). Of 41 patients with hilar mass, 18 patients were found to have lobular and segmental perfusion decrease or defect. Perfusion defect area was found in 59 patients with peripheral lung mass. The radiation dose of dual-energy enhanced scan was lower than that of

  3. Assessment of the Diagnostic Accuracy of Limited CT Scan of Paranasal Sinuses in the Identification of Sinusitis

    OpenAIRE

    Noorian, Vahid; Motaghi, Arya

    2012-01-01

    Background Paranasal sinus CT has high sensitivity and specificity for sinusitis. However, this modality is costly and involves greater radiation exposure than plain radiographs. Objectives We tried to compare 10-cut limited CT scan and standard CT scan in the diagnosis of sinusitis. Materials and Methods We conducted a cross sectional case series from August to December 2010 on 150 patients with non-randomized sampling method in academic hospitals related to medical school of Shahid Beheshti...

  4. Automated segmentation of tumors on bone scans using anatomy-specific thresholding

    Science.gov (United States)

    Chu, Gregory H.; Lo, Pechin; Kim, Hyun J.; Lu, Peiyun; Ramakrishna, Bharath; Gjertson, David; Poon, Cheryce; Auerbach, Martin; Goldin, Jonathan; Brown, Matthew S.

    2012-03-01

    Quantification of overall tumor area on bone scans may be a potential biomarker for treatment response assessment and has, to date, not been investigated. Segmentation of bone metastases on bone scans is a fundamental step for this response marker. In this paper, we propose a fully automated computerized method for the segmentation of bone metastases on bone scans, taking into account characteristics of different anatomic regions. A scan is first segmented into anatomic regions via an atlas-based segmentation procedure, which involves non-rigidly registering a labeled atlas scan to the patient scan. Next, an intensity normalization method is applied to account for varying levels of radiotracer dosing levels and scan timing. Lastly, lesions are segmented via anatomic regionspecific intensity thresholding. Thresholds are chosen by receiver operating characteristic (ROC) curve analysis against manual contouring by board certified nuclear medicine physicians. A leave-one-out cross validation of our method on a set of 39 bone scans with metastases marked by 2 board-certified nuclear medicine physicians yielded a median sensitivity of 95.5%, and specificity of 93.9%. Our method was compared with a global intensity thresholding method. The results show a comparable sensitivity and significantly improved overall specificity, with a p-value of 0.0069.

  5. Use of dual-energy CT and virtual non-calcium techniques to evaluate post-traumatic bone bruises in knees in the subacute setting

    International Nuclear Information System (INIS)

    The purpose of this study was to determine the ability of dual-energy computed tomography (DECT) and virtual non-calcium (VNCa) imaging to detect magnetic resonance imaging (MRI)-demonstrated bone bruises several weeks after unilateral knee injury. Patients with unilateral knee injury and MRI-confirmed bone bruises who had undergone a DECT scan of both knees were retrospectively identified. Two radiologists evaluated VNCa images for bruises in four regions per knee without knowing the MRI results. The mean CT numbers were calculated for the lesion-positive and lesion-negative regions of the injured knee, and the contralateral knee. Fourteen patients with a total of 36 regions positive for bone bruises on MRI were identified. The median delay between injury and DECT was 37 days (range, 11-99 days). The mean CT numbers in VNCa images for lesion-positive and lesion-negative regions were -7.6 ± 24.9 HU and -58.2 ± 19.5 HU, respectively. There were no significant differences in mean CT number between the lesion-negative regions in the injured knee and the contralateral knee. No resolution of bruising was seen before week 5, and bone bruising was still identifiable in one out of the two patients scanned at 10 weeks following injury. DECT and VNCa images can identify bone bruising for at least 10 weeks after injury. (orig.)

  6. Use of dual-energy CT and virtual non-calcium techniques to evaluate post-traumatic bone bruises in knees in the subacute setting

    Energy Technology Data Exchange (ETDEWEB)

    Ai, Songtao [Mayo Clinic, Department of Radiology, Rochester, MN (United States); Shanghai Ninth People' s Hospital, Department of Radiology, Shanghai (China); Qu, Mingliang; Glazebrook, Katrina N.; Liu, Yu; Leng, Shuai; McCollough, Cynthia H. [Mayo Clinic, Department of Radiology, Rochester, MN (United States); Rhee, Peter C. [Mayo Clinic, Department of Orthopedics, Rochester, MN (United States)

    2014-09-15

    The purpose of this study was to determine the ability of dual-energy computed tomography (DECT) and virtual non-calcium (VNCa) imaging to detect magnetic resonance imaging (MRI)-demonstrated bone bruises several weeks after unilateral knee injury. Patients with unilateral knee injury and MRI-confirmed bone bruises who had undergone a DECT scan of both knees were retrospectively identified. Two radiologists evaluated VNCa images for bruises in four regions per knee without knowing the MRI results. The mean CT numbers were calculated for the lesion-positive and lesion-negative regions of the injured knee, and the contralateral knee. Fourteen patients with a total of 36 regions positive for bone bruises on MRI were identified. The median delay between injury and DECT was 37 days (range, 11-99 days). The mean CT numbers in VNCa images for lesion-positive and lesion-negative regions were -7.6 ± 24.9 HU and -58.2 ± 19.5 HU, respectively. There were no significant differences in mean CT number between the lesion-negative regions in the injured knee and the contralateral knee. No resolution of bruising was seen before week 5, and bone bruising was still identifiable in one out of the two patients scanned at 10 weeks following injury. DECT and VNCa images can identify bone bruising for at least 10 weeks after injury. (orig.)

  7. Diagnostic values of Brain CT-Scan in Tuberculous Meningitis; A Major Health Problem in Afghanistan

    Directory of Open Access Journals (Sweden)

    N. Rasouly

    2009-01-01

    Full Text Available   "nTuberculous meningitis (TBM is the most serious complication of tuberculosis (TB in children. Afghanistan is one of the highest burden TB countries; the incidence rate is estimated at 161/100,000 of the population per year. "nEarly diagnosis of TBM is a challenge because of non-specific initial clinical features. "nDelay of diagnosis is associated with higher morbidity and mortality rate. "nRadiological evaluation has a major rule in the early diagnosis of the disease which includes chest X-Ray in case of association with pulmonary TB, cranial CT scan and MRI. "nCT scan findings in TBM are quite interesting and important and have great impact on the management of the patients. "nGenerally CT findings differ according to the presentation of patients and are usually divided into two groups of non-complicated cases and complicated cases. "nCT finding in case of non-complicated TBM can be entirely normal and sometimes we may find diffuse brain edema and lepto-meningeal inflammation with increased uptake of contrast material in CECT. The meningeal enhancement is more pronounced in the basal cisterns. "nCT finding of complicated cases are more catastrophic including communicating hydrocephalus, ventriculitis, venous or dural thrombosis with presence of delta sign (finding in sagittal sinus thrombosis, parenchymal spread (infarction, cerebritis and abscess, hygroma or empyema (epidural, subdural, and appearance of tuberculomas in the brain.  

  8. National Survey of Radiation Dose and Image Quality in Adult CT Head Scans in Taiwan.

    Directory of Open Access Journals (Sweden)

    Chung-Jung Lin

    Full Text Available The purpose of the present study was to evaluate the influence of different variables on radiation dose and image quality based on a national database.Taiwan's Ministry of Health and Welfare requested all radiology departments to complete a questionnaire for each of their CT scanners. Information gathered included all scanning parameters for CT head scans. For the present analysis, CT machines were divided into three subgroups: single slice CT (Group A; multi-detector CT (MDCT with 2-64 slices (Group B; and MDCT with more than 64 slices (Group C. Correlations between computed tomography dose index (CTDI and signal-to-noise ratio (SNR with cumulated tube rotation number (CTW(n and cumulated tube rotation time (CTW(s, and sub group analyses of CTDI and SNR across the three groups were performed.CTDI values demonstrated a weak correlation (r = 0.33 with CTW(n in Group A. SNR values demonstrated a weak negative correlation (r = -0.46 with CTW(n in Group C. MDCT with higher slice numbers used more tube potential resulting in higher effective doses. There were both significantly lower CTDI and SNR values in helical mode than in axial mode in Group B, but not Group C.CTW(n and CTW(s did not influence radiation output. Helical mode is more often used in MDCT and results in both lower CTDI and SNR compared to axial mode in MDCT with less than 64 slices.

  9. Splenic hemochromatosis incidentally found on Tc-99m MDP bone scan in a chronic myelogenous leukemia patient who received bone marrow transplantation

    Energy Technology Data Exchange (ETDEWEB)

    Ahn, Byeong Cheol; Seo, Ji Hyoung; Bae, Jin Ho; Jeong, Sin Young; Lee, Jae Tae; Lee, Kyu Bo [School of Medicine, Kyungpook National Univ., Daegu (Korea, Republic of)

    2004-02-01

    Tc-99m MDP bone scan was performed to evaluate a generalized bone pain in a 24-year-old male chronic myelogenous leukemia patient who received bone marrow transplantation at 7 months ago. The patient had received large amounts of blood transfusion for managing symptoms related to anemia. Bone scan revealed substantial splenic tracer uptake. Magnetic resonance image and laboratory evidence of hemochromatosis suggests that the presence of large quantities of iron in the spleen of this patient may have been responsible for the splenic uptake of the bone scanning agent. The authors report a c ase of splenic hemochromatosis incidentally found on Tc-99m MDP bone scan.

  10. Automatic detection of axillary lymphadenopathy on CT scans of untreated chronic lymphocytic leukemia patients

    Science.gov (United States)

    Liu, Jiamin; Hua, Jeremy; Chellappa, Vivek; Petrick, Nicholas; Sahiner, Berkman; Farooqui, Mohammed; Marti, Gerald; Wiestner, Adrian; Summers, Ronald M.

    2012-03-01

    Patients with chronic lymphocytic leukemia (CLL) have an increased frequency of axillary lymphadenopathy. Pretreatment CT scans can be used to upstage patients at the time of presentation and post-treatment CT scans can reduce the number of complete responses. In the current clinical workflow, the detection and diagnosis of lymph nodes is usually performed manually by examining all slices of CT images, which can be time consuming and highly dependent on the observer's experience. A system for automatic lymph node detection and measurement is desired. We propose a computer aided detection (CAD) system for axillary lymph nodes on CT scans in CLL patients. The lung is first automatically segmented and the patient's body in lung region is extracted to set the search region for lymph nodes. Multi-scale Hessian based blob detection is then applied to detect potential lymph nodes within the search region. Next, the detected potential candidates are segmented by fast level set method. Finally, features are calculated from the segmented candidates and support vector machine (SVM) classification is utilized for false positive reduction. Two blobness features, Frangi's and Li's, are tested and their free-response receiver operating characteristic (FROC) curves are generated to assess system performance. We applied our detection system to 12 patients with 168 axillary lymph nodes measuring greater than 10 mm. All lymph nodes are manually labeled as ground truth. The system achieved sensitivities of 81% and 85% at 2 false positives per patient for Frangi's and Li's blobness, respectively.

  11. Aphasia caused by intracerebral hemorrhage; CT-scan findings and prognosis

    Energy Technology Data Exchange (ETDEWEB)

    Furuya, Kazuhide; Segawa, Hiromu; Shiokawa, Yoshiaki; Hasegawa, Isao; Sano, Keiji (Fuji Brain Institute and Hospital, Shizuoka (Japan))

    1992-10-01

    It is generally accepted that cases of aphasia can be divided into several groups according to verbal fluency, auditory comprehension, and repetition abilities. Although many authors have studied aphasia and its location by means of a CT scan, the primary lesion on a CT scan with regard to the subtypes of aphasia still remains controversial. In this report we present our new CT classification for the syndromes of aphasia and the prognosis. Twenty-one patients with intracerebral hematoma (ICH) were followed up for more than 3 months after onset. ICH was classified according to the mode of the horizontal extension of the hematoma on a CT scan. Four lines were decided as follows: Line (a) is between the anterior horn of the lateral ventricle and the midpoint of the third ventricle; Line (b) is the vertical line to the saggital line which originates from the midpoint of the third ventricle; Line (c) is between the trigone of the lateral ventricle and the midpoint of the third ventricle. The CT classification consisted of 4 types: in Type A, ICH was located anterior to line (a); in Type B, ICH was located between line (a) and line (b); in Type C, ICH was located between line (b) and line (c); Type B+C, was a combination of Type B and Type C. Transcortical motor aphasia belonged to the Type A group. Transcortical sensory aphasia belonged to the Type B and Type B+C groups. Wernicke's and anomic aphasia belonged to the Type C group. Conduction and global aphasia belonged to the Type B+C group. Pure Broca's aphasia could not be observed in this series. Several relationships between the syndromes of aphasia and its CT findings were evident. On the other hand, the syndromes of aphasia and the degree of recovery were not correlated, except for global aphasia. (author).

  12. Micro-CT analyses of historical bone samples presenting with osteomyelitis

    International Nuclear Information System (INIS)

    Osteomyelitis is an inflammation of the bone marrow mainly caused by bacteria such as Staphylococcus aureus. It typically affects long bones, e.g. femora, tibiae and humeri. Recently micro-computed tomography (μCT) techniques offer the opportunity to investigate bone micro-architecture in great detail. Since there is no information on long bone microstructure in osteomyelitis, we studied historic bone samples with osteomyelitis by μCT. We investigated 23 femora of 22 individuals suffering from osteomyelitis provided by the Collection of Anatomical Pathology, Museum of Natural History, Vienna (average age 44 ±19 years); 9 femora from body donors made available by the Department of Applied Anatomy, Medical University of Vienna (age range, 56-102 years) were studied as controls. Bone microstructure was assessed by μCT VISCOM X 8060 II with a minimal resolution of 18 μm. In the osteomyelitic femora, most prominent alterations were seen in the cortical compartment. In 71.4 % of the individuals with osteomyelitis, cortical porosity occurred. 57.1 % of the individuals showed cortical thinning. In 42.9 % trabecularisation of cortical bone was observed. Osteomyelitis is associated with severe alterations of cortical bone structure otherwise typically observed at old age such as cortical porosity and cortical thinning. (orig.)

  13. Micro-CT analyses of historical bone samples presenting with osteomyelitis

    Energy Technology Data Exchange (ETDEWEB)

    Lamm, C.; Pietschmann, P. [Medical University Vienna (MUV), Department of Pathophysiology and Allergy Research, Center for Pathophysiology, Infectiology and Immunology, Vienna (Austria); Dockner, M.; Weber, G.W. [University of Vienna, Department of Anthropology, Vienna (Austria); University of Vienna, Core Facility for Micro-Computed Tomography, Vienna (Austria); Pospischek, B.; Winter, E.; Patzak, B. [Museum of Natural History (NHM), Collection of Anatomical Pathology in the Madhouse Tower, Vienna (Austria); Pretterklieber, M. [Medical University of Vienna (MUV), Department of Applied Anatomy, Vienna (Austria)

    2015-10-15

    Osteomyelitis is an inflammation of the bone marrow mainly caused by bacteria such as Staphylococcus aureus. It typically affects long bones, e.g. femora, tibiae and humeri. Recently micro-computed tomography (μCT) techniques offer the opportunity to investigate bone micro-architecture in great detail. Since there is no information on long bone microstructure in osteomyelitis, we studied historic bone samples with osteomyelitis by μCT. We investigated 23 femora of 22 individuals suffering from osteomyelitis provided by the Collection of Anatomical Pathology, Museum of Natural History, Vienna (average age 44 ±19 years); 9 femora from body donors made available by the Department of Applied Anatomy, Medical University of Vienna (age range, 56-102 years) were studied as controls. Bone microstructure was assessed by μCT VISCOM X 8060 II with a minimal resolution of 18 μm. In the osteomyelitic femora, most prominent alterations were seen in the cortical compartment. In 71.4 % of the individuals with osteomyelitis, cortical porosity occurred. 57.1 % of the individuals showed cortical thinning. In 42.9 % trabecularisation of cortical bone was observed. Osteomyelitis is associated with severe alterations of cortical bone structure otherwise typically observed at old age such as cortical porosity and cortical thinning. (orig.)

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

    Medline Plus

    Full Text Available ... image recording plate . Bones appear white on the x-ray; soft tissues show up in shades of gray and ... of CT is its ability to image bone, soft tissue and blood vessels all at the same time. Unlike conventional x-rays, CT scanning provides very detailed images of many ...

  15. Dual-energy CT angiography of pelvic and lower extremity arteries: dual-energy bone subtraction versus manual bone subtraction

    International Nuclear Information System (INIS)

    Aim: To analyse the effect of dual-energy bone subtraction (DEBS) on the image quality of peripheral computed tomography (CT) angiograms. Materials and methods: Twenty patients underwent dual-energy CT angiography of the pelvic and lower extremity arteries using commercially available equipment. Two different methods of image processing were employed for each CT angiographic dataset: (1) DEBS, and (2) manual bone subtraction (MBS). Effects on vessel visibility and artificial vessel alterations were compared. Results: Bone removal, and the resultant visibility of vessel segments, were significantly better with DEBS than with MBS (p = 0.011). The overall frequency of vessel-related alterations was lower in MBS compared with DEBS (p = 0.001). Specifically, in the 249 vessel segments with calcified plaques, MBS generated fewer vessel alterations than DEBS (p < 0.001). In the 309 vessel segments without calcified plaques, there was no difference in vessel alteration between the two techniques (p = 0.22). Conclusion: DEBS facilitates bone removal in peripheral CT angiography, but generates more vessel alterations, particularly in the presence of calcified plaque.

  16. Dual-energy CT angiography of pelvic and lower extremity arteries: dual-energy bone subtraction versus manual bone subtraction

    Energy Technology Data Exchange (ETDEWEB)

    Yamamoto, S., E-mail: syamamoto@gmail.co [David Geffen School of Medicine, Department of Radiology, University of California-Los Angeles, Los Angeles (United States); McWilliams, J.; Arellano, C.; Marfori, W.; Cheng, W.; Mcnamara, T.; Quinones-Baldrich, W.J.; Ruehm, S.G. [David Geffen School of Medicine, Department of Radiology, University of California-Los Angeles, Los Angeles (United States)

    2009-11-15

    Aim: To analyse the effect of dual-energy bone subtraction (DEBS) on the image quality of peripheral computed tomography (CT) angiograms. Materials and methods: Twenty patients underwent dual-energy CT angiography of the pelvic and lower extremity arteries using commercially available equipment. Two different methods of image processing were employed for each CT angiographic dataset: (1) DEBS, and (2) manual bone subtraction (MBS). Effects on vessel visibility and artificial vessel alterations were compared. Results: Bone removal, and the resultant visibility of vessel segments, were significantly better with DEBS than with MBS (p = 0.011). The overall frequency of vessel-related alterations was lower in MBS compared with DEBS (p = 0.001). Specifically, in the 249 vessel segments with calcified plaques, MBS generated fewer vessel alterations than DEBS (p < 0.001). In the 309 vessel segments without calcified plaques, there was no difference in vessel alteration between the two techniques (p = 0.22). Conclusion: DEBS facilitates bone removal in peripheral CT angiography, but generates more vessel alterations, particularly in the presence of calcified plaque.

  17. CT pre-operative planning of a new semi-implantable bone conduction hearing device

    Energy Technology Data Exchange (ETDEWEB)

    Law, Eric K.C.; Bhatia, Kunwar S.S. [Prince of Wales Hospital, The Chinese University of Hong Kong, Department of Imaging and Interventional Radiology, Hong Kong, SAR (China); Tsang, Willis S.S.; Tong, Michael C.F. [Prince of Wales Hospital, The Chinese University of Hong Kong, Department of Otorhinolaryngology, Head and Neck Surgery, Hong Kong, SAR (China); Shi, Lin [The Chinese University of Hong Kong, Department of Medicine and Therapeutics, Hong Kong, SAR (China); The Chinese University of Hong Kong, Chow Yuk Ho Technology Center for Innovative Medicine, Hong Kong, SAR (China)

    2016-06-15

    Accommodating a novel semi-implantable bone conduction hearing device within the temporal bone presents challenges for surgical planning. This study describes the utility of CT in pre-operative assessment of such an implant. Retrospective review of pre-operative CT, clinical and surgical records of 16 adults considered for device implantation. Radiological suitability was assessed on CT using 3D simulation software. Antero-posterior (AP) dimensions of the mastoid bone and minimum skull thickness were measured. CT planning results were correlated with operative records. Eight and five candidates were suitable for device placement in the transmastoid and retrosigmoid positions, respectively, and three were radiologically unsuitable. The mean AP diameter of the mastoid cavity was 14.6 mm for the transmastoid group and 4.6 mm for the retrosigmoid group (p < 0.05). Contracted mastoid and/or prior surgery were predisposing factors for unsuitability. Four transmastoid and five retrosigmoid positions required sigmoid sinus/dural depression and/or use of lifts due to insufficient bone capacity. A high proportion of patients being considered have contracted or operated mastoids, which reduces the feasibility of the transmastoid approach. This finding combined with the complex temporal bone geometry illustrates the importance of careful CT evaluation using 3D software for precise device simulation. (orig.)

  18. Selection of colon cancer patients for neoadjuvant chemotherapy by preoperative CT scan

    DEFF Research Database (Denmark)

    Nørgaard, Anne; Dam, Claus; Jakobsen, Anders;

    2014-01-01

    Abstract Objective: Preoperative staging is essential to plan correct treatment of colon cancer and calls for objective, accurate methods for the introduction of neoadjuvant chemotherapy, which represents a new treatment option. Purpose: To evaluate the diagnostic accuracy of multislice computed...... tomography (CT) in local staging of colon cancer correlated with histopathological parameters, including criteria for adjuvant chemotherapy. Material and methods. A total of 74 included patients had preoperative CT scans and surgical resection of their colon tumors. Tumor stage (T-stage), extramural tumor...

  19. Thromboembolic Complications Following Spine Surgery Assessed with Spiral CT Scans: DVT/PE Following Spine Surgery

    OpenAIRE

    Kim, Han Jo; Walcott-Sapp, Sarah; Adler, Ronald S.; Pavlov, Helene; Boachie-Adjei, Oheneba; Westrich, Geoffrey H.

    2010-01-01

    Spine surgery is associated with a significant risk of postoperative pulmonary embolism (PE) and/or deep vein thrombosis (DVT). The goal of this study was to determine which symptoms and risk factors were associated with spiral CT scans positive for PE and/or DVT in the postoperative spine surgery patient. We conducted a retrospective review of all spine patients who underwent a postoperative CT to rule out PE during the period of March 2004–February 2006. The type of surgical procedure, risk...

  20. Quality of planar whole-body bone scan interpretations - a nationwide survey

    Energy Technology Data Exchange (ETDEWEB)

    Sadik, May; Suurkula, Madis [Sahlgrenska University Hospital, Department of Clinical Physiology, Goeteborg (Sweden); Hoeglund, Peter [Lund University Hospital, Competence Center for Clinical Research, Lund (Sweden); Jaerund, Andreas [EXINI Diagnostics AB, Lund (Sweden); Edenbrandt, Lars [Sahlgrenska University Hospital, Department of Clinical Physiology, Goeteborg (Sweden); Lund University Research Program in Medical Informatics, Malmoe University Hospital, Department of Clinical Sciences, Malmoe, Malmoe (Sweden)

    2008-08-15

    The purpose of this study was to investigate, in a nationwide study, the inter-observer variation and performance in interpretations of bone scans regarding the presence or absence of bone metastases. Bone scan images from 59 patients with breast or prostate cancer, who had undergone scintigraphy due to suspected bone metastatic disease, were studied. The patients were selected to reflect the spectrum of pathology found in everyday clinical work. Whole body images, anterior and posterior views, were sent to all 30 hospitals in Sweden that perform bone scans. Thirty-seven observers from 18 hospitals agreed to participate in the study. They were asked to classify each of the patient studies regarding the presence of bone metastasis, using a four-point scale. Each observer's classifications were pairwise compared with the classifications made by all the other observers, resulting in 666 pairs of comparisons. The interpretations of the 37 observers were also compared with the final clinical assessment, which was based on follow-up scans and other clinical data. On average, two observers agreed on 64% of the bone scan classifications. Kappa values ranged between 0.16 and 0.82, with a mean of 0.48. Sensitivity and specificity for the observers compared with the final clinical assessment were 77% and 96%, respectively, for detecting bone metastases in planar whole-body bone scanning. Moderate inter-observer agreement was found when observers were compared pairwise. False-negative errors seem to be the major problem in the interpretations of bone scan images, whilst the specificities for the observers were high. (orig.)

  1. When is a bone scan study appropriate in asymptomatic men diagnosed with prostate cancer?

    Institute of Scientific and Technical Information of China (English)

    Raj P.Pal; Thivyaan Thiruudaian; Masood A.Khan

    2008-01-01

    Aims: To determine when a bone scan investigation is appropriate in asymptomatic men diagnosed with prostate cancer. Methods: Between November 2005 and July 2006, 317 men with prostate cancer underwent a bone scan study; 176 men fulfilled the inclusion criteria. Prostate-specific antigen (PSA) cut-offs as well as univariate and multivariate logistic regression analyses using digital rectal examination finding, biopsy Gleason scores and age were performed to determine when a bone scan study is likely to be of value. Results: Only 1/61 men (1.6%) with a serum PSA ≤ 20 ng/mL had a positive bone scan. However, 2/38 men (4.7%) with a serum PSA 20.1-40.0 ng/mL, 3/20 men (15%) with a serum PSA 40.1-60.0 ng/mL, 7/19 men (36.8%) with a serum PSA 60.1-100.0 ng/mL and 19/38 men (50%) with a serum PSA > 100.0 ng/mL had positive bone scans. Univariate and multivariate logistic regression analyses were uninformative in these groups. Conclusion: Based on our findings, a bone scan is of limited value in asymptomatic prostate cancer patients presenting PSA ≤ 20 ng/mL. Therefore, this investigation can be eliminated unless a curative treatment is contemplated. Furthermore, digital rectal examination finding, biopsy Gleason score and age are unhelpful in predicting those who might harbor bone metastasis.

  2. CT Scan of Thirteen Natural Mummies Dating Back to the XVI-XVIII Centuries: An Emerging Tool to Investigate Living Conditions and Diseases in History

    Science.gov (United States)

    Petrella, Enrico; Piciucchi, Sara; Feletti, Francesco; Barone, Domenico; Piraccini, Antonella; Minghetti, Caterina; Gruppioni, Giorgio; Poletti, Venerino; Bertocco, Mauro; Traversari, Mirko

    2016-01-01

    Objectives To correlate the radiologic findings detected with computed tomography scan with anthropological data in 13 naturally mummified bodies discovered during works of recovery of an ancient church in a crypt in Roccapelago, in the Italian Apennines. Methods From a group of about sixty not-intentionally mummified bodies, thirteen were selected to be investigated with volumetric computed tomography (CT). Once CT scan was performed, axial images were processed to gather MPR and Volume Rendering reconstructions. Elaborations of these images provided anthropometric measurements and a non-invasive analysis of the residual anatomical structures. For each body the grade of preservation and the eventual pathological changes were recorded. Furthermore, in order to identify nutritional and occupational markers, radiologic signs of bone tropism and degenerative changes were analysed and graded. Results Mummies included seven females and six males, with an estimated age ranging from 20 to 60 years. The first relevant finding identified was a general low grade of preservation, due to the lack of anatomic tissues different from bones, tendons and dehydrated skin. The low grade of preservation was related to the natural process of mummification. Analysing bone degenerative changes on CT scan, the majority of the bodies had significant occupational markers consisting of arthritis in the spine, lower limbs and shoulders even in young age. Few were the pathological findings identified. Among these, the most relevant included a severe bilateral congenital hip dysplasia and a wide osteolytic lesion involving left orbit and petrous bone that was likely the cause of death. Conclusions Although the low grade of preservation of these mummies, the multidisciplinary approach of anthropologists and radiologists allowed several important advances in knowledge for the epidemiology of Roccapelago. First of all, a profile of living conditions was delineated. It included occupational and

  3. CT Scan of Thirteen Natural Mummies Dating Back to the XVI-XVIII Centuries: An Emerging Tool to Investigate Living Conditions and Diseases in History.

    Directory of Open Access Journals (Sweden)

    Enrico Petrella

    Full Text Available To correlate the radiologic findings detected with computed tomography scan with anthropological data in 13 naturally mummified bodies discovered during works of recovery of an ancient church in a crypt in Roccapelago, in the Italian Apennines.From a group of about sixty not-intentionally mummified bodies, thirteen were selected to be investigated with volumetric computed tomography (CT. Once CT scan was performed, axial images were processed to gather MPR and Volume Rendering reconstructions. Elaborations of these images provided anthropometric measurements and a non-invasive analysis of the residual anatomical structures. For each body the grade of preservation and the eventual pathological changes were recorded. Furthermore, in order to identify nutritional and occupational markers, radiologic signs of bone tropism and degenerative changes were analysed and graded.Mummies included seven females and six males, with an estimated age ranging from 20 to 60 years. The first relevant finding identified was a general low grade of preservation, due to the lack of anatomic tissues different from bones, tendons and dehydrated skin. The low grade of preservation was related to the natural process of mummification. Analysing bone degenerative changes on CT scan, the majority of the bodies had significant occupational markers consisting of arthritis in the spine, lower limbs and shoulders even in young age. Few were the pathological findings identified. Among these, the most relevant included a severe bilateral congenital hip dysplasia and a wide osteolytic lesion involving left orbit and petrous bone that was likely the cause of death.Although the low grade of preservation of these mummies, the multidisciplinary approach of anthropologists and radiologists allowed several important advances in knowledge for the epidemiology of Roccapelago. First of all, a profile of living conditions was delineated. It included occupational and nutritional conditions

  4. Leukemia and brain tumors among children after radiation exposure from CT scans: design and methodological opportunities of the Dutch Pediatric CT Study.

    Science.gov (United States)

    Meulepas, Johanna M; Ronckers, Cécile M; Smets, Anne M J B; Nievelstein, Rutger A J; Jahnen, Andreas; Lee, Choonsik; Kieft, Mariëtte; Laméris, Johan S; van Herk, Marcel; Greuter, Marcel J W; Jeukens, Cécile R L P N; van Straten, Marcel; Visser, Otto; van Leeuwen, Flora E; Hauptmann, Michael

    2014-04-01

    Computed tomography (CT) scans are indispensable in modern medicine; however, the spectacular rise in global use coupled with relatively high doses of ionizing radiation per examination have raised radiation protection concerns. Children are of particular concern because they are more sensitive to radiation-induced cancer compared with adults and have a long lifespan to express harmful effects which may offset clinical benefits of performing a scan. This paper describes the design and methodology of a nationwide study, the Dutch Pediatric CT Study, regarding risk of leukemia and brain tumors in children after radiation exposure from CT scans. It is a retrospective record-linkage cohort study with an expected number of 100,000 children who received at least one electronically archived CT scan covering the calendar period since the introduction of digital archiving until 2012. Information on all archived CT scans of these children will be obtained, including date of examination, scanned body part and radiologist's report, as well as the machine settings required for organ dose estimation. We will obtain cancer incidence by record linkage with external databases. In this article, we describe several approaches to the collection of data on archived CT scans, the estimation of radiation doses and the assessment of confounding. The proposed approaches provide useful strategies for data collection and confounder assessment for general retrospective record-linkage studies, particular those using hospital databases on radiological procedures for the assessment of exposure to ionizing or non-ionizing radiation. PMID:24748424

  5. Raman and CT scan mapping of chalcogenide glass diffusion generated gradient index profiles

    Science.gov (United States)

    Lindberg, G. P.; Berg, R. H.; Deegan, J.; Benson, R.; Salvaggio, P. S.; Gross, N.; Weinstein, B. A.; Gibson, D.; Bayya, S.; Sanghera, J.; Nguyen, V.; Kotov, M.

    2016-05-01

    Metrology of a gradient index (GRIN) material is non-trivial, especially in the realm of infrared and large refractive index. Traditional methods rely on index matching fluids which are not available for indexes as high as those found in the chalcogenide glasses (2.4-3.2). By diffusing chalcogenide glasses of similar composition one can blend the properties in a continuous way. In an effort to measure this we will present data from both x-ray computed tomography scans (CT scans) and Raman mapping scans of the diffusion profiles. Proof of concept measurements on undiffused bonded sheets of chalcogenide glasses were presented previously. The profiles measured will be of axially stacked sheets of chalcogenide glasses diffused to create a linear GRIN profile and nested tubes of chalcogenide glasses diffused to create a radial parabolic GRIN profile. We will show that the x-ray absorption in the CT scan and the intensity of select Raman peaks spatially measured through the material are indicators of the concentration of the diffusion ions and correlate to the spatial change in refractive index. We will also present finite element modeling (FEM) results and compare them to post precision glass molded (PGM) elements that have undergone CT and Raman mapping.

  6. Evaluation in the use of bismuth shielding on cervical spine CT scan using a male phantom

    Energy Technology Data Exchange (ETDEWEB)

    Aleme, C.; Mourao, A. P. [Centro Federal de Educacion Tecnologica de Minas Gerais, Biomedical Engineering Center, Belo Horizonte - MG (Brazil); Lyra, M. A., E-mail: carolinaaleme@gmail.com [Universidad Federal de Minas Gerais, Department of Nuclear Engineering, Av. Pdte. Antonio Carlos 6627, Pampulha, 31270-91 Belo Horizonte - MG (Brazil)

    2014-08-15

    The cervical spine is the region of the column that articulates the head and chest. The tests of computed tomography (CT) performed in this region have as main objectives to diagnose fractures, dislocations and tumors. In CT scans the cervical spine volume is limited by the foramen Magnum and the first thoracic vertebra. In this region is the thyroid that is directly irradiated by X-ray beam during cervical scan. Based on this information, it was studied the dose variation deposited in thyroid and in nearby organs, such as: lenses, spinal cord in the foramen Magnum region and breasts, with and without the use of bismuth protector. In this study was used a male anthropomorphic phantom and thermoluminescent s dosimeters (TLD-100) were required to register the individual doses in the organs of interest. CT scans were performed on a GE Bright Speed scanner of 32 channels. With the data obtained, it was found the organ dose variation. The largest recorded dose was in the thyroid. Comparing two scans it was possible to note that the use of the bismuth protector promoted a 26% reduction in the thyroid dose and an increase in the lens dose. (Author)

  7. Recognition of fibrous dysplasia of bone mimicking skeletal metastasis on 18F-FDG PET/CT imaging

    International Nuclear Information System (INIS)

    Fibrous dysplasia of bone (FDB) reveals intense 18F-FDG uptake mimicking metastases on 18F-FDG PET/CT. We reviewed sites of FDB revealed by 18F-FDG PET/CT imaging to allow identification of this abnormality. Eleven patients (7 male, 4 female, aged 16-78 years) were evaluated after 55 MBq (0.15 mCi)/kg 18F-FDG utilizing a 16-slice multiple detector CT (MDCT) whole-body PET scanner, with LOR algorithm 3D reconstruction. One- and 2-h imaging was performed in 9 patients. Standard uptake value (SUV) for each lesion, on early and delayed imaging, was calculated. Lesions were confirmed in 6 patients by biopsy. The PET images correlated with MDCT to establish the imaging characteristics. Solitary lesions were found in 4 patients, two lesions in 1 patient, and in 6 patients there were multiple bone lesions. The SUVearly ranged from 1.23 to 9.64 with an average of 3.76 ± 2.40. The SUVdelayed ranged from 1.76 to 11.42 with an average of 4.51 ± 3.07. The SUVdelayed decreased or increased slightly (-31% to 5%) in 6 of our patients, and increased significantly (11% to 39%) in 3. There was a negative correlation between SUVs and age, as well as the number of affected bones. In our study, FDB had wide skeletal distribution with variability of 18F-FDG uptake and CT appearance. SUV in the delayed stage was seen to either decrease or increase on dual-time 18F-FDG PET scanning. It is very important to recognize the characteristics of this skeletal dysplasia to allow differentiation from skeletal metastasis. (orig.)

  8. Evaluation of variation of voltage (kV) absorbed dose in chest CT scans

    International Nuclear Information System (INIS)

    Computed tomography (CT) is one of the most important diagnostic techniques images today. The increasing utilization of CT implies a significant increase of population exposure to ionizing radiation. Optimization of practice aims to reduce doses to patients because the image quality is directly related to the diagnosis. You can decrease the amount of dose to the patient, and maintain the quality of the image. There are several parameters that can be manipulated in a CT scan and these parameters can be used to reduce the energy deposited in the patient. Based on this, we analyzed the variation of dose deposited in the lungs, breasts and thyroid, by varying the supply voltage of the tube. Scans of the thorax were performed following the protocol of routine chest with constant and variable current for the same applied voltage. Moreover, a female phantom was used and thermoluminescent dosimeters (TLD-100), model bat, were used to record the specific organ doses. Scans were performed on a GE CT scanner, model 64 Discovery channels. Higher doses were recorded for the voltage of 120 kV with 200 mAs in the lungs (22.46 mGy) and thyroid (32.22 mGy). For scans with automatic mAs, variable between 100 and 440, this same tension contributed to the higher doses. The best examination in terms of the dose that was used with automatic 80 kV mAs, whose lungs and thyroid received lower dose. For the best breast exam was 100 kV. Since the increase in the 80 kV to 100 kV no impact so much the dose deposited in the lungs, it can be concluded that lowering the applied voltage to 100 kV resulted in a reduction in the dose absorbed by the patient. These results can contribute to optimizing scans of the chest computed tomography