WorldWideScience

Sample records for brain ct images

  1. Image reconstruction for brain CT slices

    Institute of Scientific and Technical Information of China (English)

    吴建明; 施鹏飞

    2004-01-01

    Different modalities in biomedical images, like CT, MRI and PET scanners, provide detailed cross-sectional views of human anatomy. This paper introduces three-dimensional brain reconstruction based on CT slices. It contains filtering, fuzzy segmentation, matching method of contours, cell array structure and image animation. Experimental results have shown its validity. The innovation is matching method of contours and fuzzy segmentation algorithm of CT slices.

  2. Brain CT image and handedness of schizophrenia

    International Nuclear Information System (INIS)

    Brain CT images were reviewed of 98 schizophrenic patients and 90 healthy persons in relation to handedness and aging. CT images were further reconstructed to examine morphologically subtle changes in each region. Schizophrenic patients had progressive brain atrophy and dilated lateral ventricles, especially on the left side and in the posterior part of the lateral ventricle. These findings were more marked in left-handed than in right-handed schizophrenic patients. According to age groups, there were significant differences between schizophrenic and normal persons over the age of 40. The incidence of left handedness was significantly higher in schizophrenic patients in their fourties than the age-matched normal persons (31.4% vs 15.1%). Morphological abnormality and laterality might be due to the same pathologic consequences. (N.K.)

  3. Whole-brain dynamic CT angiography and perfusion imaging

    Energy Technology Data Exchange (ETDEWEB)

    Orrison, W.W. [CHW Nevada Imaging Company, Nevada Imaging Centers, Spring Valley, Las Vegas, NV (United States); College of Osteopathic Medicine, Touro University Nevada, Henderson, NV (United States); Department of Health Physics and Diagnostic Sciences, University of Nevada Las Vegas, Las Vegas, NV (United States); Department of Medical Education, University of Nevada School of Medicine, Reno, NV (United States); Snyder, K.V.; Hopkins, L.N. [Department of Neurosurgery, Millard Fillmore Gates Circle Hospital, Buffalo, NY (United States); Roach, C.J. [School of Life Sciences, University of Nevada Las Vegas, Las Vegas, NV (United States); Advanced Medical Imaging and Genetics (Amigenics), Las Vegas, NV (United States); Ringdahl, E.N. [Department of Psychology, University of Nevada Las Vegas, Las Vegas, NV (United States); Nazir, R. [Shifa International Hospital, Islamabad (Pakistan); Hanson, E.H., E-mail: eric.hanson@amigenics.co [College of Osteopathic Medicine, Touro University Nevada, Henderson, NV (United States); Department of Health Physics and Diagnostic Sciences, University of Nevada Las Vegas, Las Vegas, NV (United States); Advanced Medical Imaging and Genetics (Amigenics), Las Vegas, NV (United States)

    2011-06-15

    The availability of whole brain computed tomography (CT) perfusion has expanded the opportunities for analysing the haemodynamic parameters associated with varied neurological conditions. Examples demonstrating the clinical utility of whole-brain CT perfusion imaging in selected acute and chronic ischaemic arterial neurovascular conditions are presented. Whole-brain CT perfusion enables the detection and focused haemodynamic analyses of acute and chronic arterial conditions in the central nervous system without the limitation of partial anatomical coverage of the brain.

  4. Whole-brain dynamic CT angiography and perfusion imaging

    International Nuclear Information System (INIS)

    The availability of whole brain computed tomography (CT) perfusion has expanded the opportunities for analysing the haemodynamic parameters associated with varied neurological conditions. Examples demonstrating the clinical utility of whole-brain CT perfusion imaging in selected acute and chronic ischaemic arterial neurovascular conditions are presented. Whole-brain CT perfusion enables the detection and focused haemodynamic analyses of acute and chronic arterial conditions in the central nervous system without the limitation of partial anatomical coverage of the brain.

  5. MR to CT Registration of Brains using Image Synthesis

    OpenAIRE

    Roy, Snehashis; Carass, Aaron; Jog, Amod; Prince, Jerry L.; Lee, Junghoon

    2014-01-01

    Computed tomography (CT) is the standard imaging modality for patient dose calculation for radiation therapy. Magnetic resonance (MR) imaging (MRI) is used along with CT to identify brain structures due to its superior soft tissue contrast. Registration of MR and CT is necessary for accurate delineation of the tumor and other structures, and is critical in radiotherapy planning. Mutual information (MI) or its variants are typically used as a similarity metric to register MRI to CT. However, u...

  6. Intracranial Hemorrhage Annotation for CT Brain Images

    Directory of Open Access Journals (Sweden)

    Tong Hau Lee

    2011-01-01

    Full Text Available In this paper, we created a decision-making model to detect intracranial hemorrhage and adopted Expectation Maximization(EM segmentation to segment the Computed Tomography (CT images. In this work, basically intracranial hemorrhage is classified into two main types which are intra-axial hemorrhage and extra-axial hemorrhage. In order to ease classification, contrast enhancement is adopted to finetune the contrast of the hemorrhage. After that, k-means is applied to group the potential and suspicious hemorrhagic regions into one cluster. The decision-making process is to identify whether the suspicious regions are hemorrhagic regions or non-regions of interest. After the hemorrhagic detection, the images are segmented into brain matter and cerebrospinal fluid (CSF by using expectation-maximization (EM segmentation. The acquired experimental results are evaluated in terms of recall and precision. The encouraging results have been attained whereby the proposed system has yielded 0.9333 and 0.8880 precision for extra-axial and intra-axial hemorrhagic detection respectively, whereas recall rate obtained is 0.9245 and 0.8043 for extra-axial and intra-axial hemorrhagic detection respectively.

  7. Intracranial Hemorrhage Annotation for CT Brain Images

    OpenAIRE

    Tong Hau Lee; Mohammad Faizal Ahmad Fauzi; Su-Cheng Haw

    2011-01-01

    In this paper, we created a decision-making model to detect intracranial hemorrhage and adopted Expectation Maximization(EM) segmentation to segment the Computed Tomography (CT) images. In this work, basically intracranial hemorrhage is classified into two main types which are intra-axial hemorrhage and extra-axial hemorrhage. In order to ease classification, contrast enhancement is adopted to finetune the contrast of the hemorrhage. After that, k-means is applied to group the potential and s...

  8. CT images in brain metastases of the primary lung cancer

    International Nuclear Information System (INIS)

    Computed tomography (CT) of the brain was carried out in 366 patients with lung cancer in order to evaluate brain metastases. Suggestive evidences of metastases such as low density or contrast enhancement were observed in 65 cases (18%), although 26% of the metastatic cases revealed no signs or symptoms of neurological disorders. These facts emphasize that brain CT should be conducted in all patients with lung cancer, irrespective of signs and symptoms. A solitary lesion was noted in 37 out of 65 metastatic cases. More than 80% of the metastatic lesions were demonstrated as iso-density on plain CT films and were enhanced by intravenous injection of contrast medium. Although CT images of metastatic lesions reveal certain characteristic appearances according to the histologic type of the primary cancer, perifocal low density and central cavitation were observed independent of histologic type. (author)

  9. Histogram analysis with automated extraction of brain-tissue region from whole-brain CT images

    OpenAIRE

    Kondo, Masatoshi; Yamashita, Koji; Yoshiura, Takashi; Hiwatash, Akio; Shirasaka, Takashi; Arimura, Hisao; Nakamura, Yasuhiko; Honda, Hiroshi

    2015-01-01

    To determine whether an automated extraction of the brain-tissue region from CT images is useful for the histogram analysis of the brain-tissue region was studied. We used the CT images of 11 patients. We developed an automatic brain-tissue extraction algorithm. We evaluated the similarity index of this automated extraction method relative to manual extraction, and we compared the mean CT number of all extracted pixels and the kurtosis and skewness of the distribution of CT numbers of all ext...

  10. Automated delineation of stroke lesions using brain CT images

    Directory of Open Access Journals (Sweden)

    Céline R. Gillebert

    2014-01-01

    Full Text Available Computed tomographic (CT images are widely used for the identification of abnormal brain tissue following infarct and hemorrhage in stroke. Manual lesion delineation is currently the standard approach, but is both time-consuming and operator-dependent. To address these issues, we present a method that can automatically delineate infarct and hemorrhage in stroke CT images. The key elements of this method are the accurate normalization of CT images from stroke patients into template space and the subsequent voxelwise comparison with a group of control CT images for defining areas with hypo- or hyper-intense signals. Our validation, using simulated and actual lesions, shows that our approach is effective in reconstructing lesions resulting from both infarct and hemorrhage and yields lesion maps spatially consistent with those produced manually by expert operators. A limitation is that, relative to manual delineation, there is reduced sensitivity of the automated method in regions close to the ventricles and the brain contours. However, the automated method presents a number of benefits in terms of offering significant time savings and the elimination of the inter-operator differences inherent to manual tracing approaches. These factors are relevant for the creation of large-scale lesion databases for neuropsychological research. The automated delineation of stroke lesions from CT scans may also enable longitudinal studies to quantify changes in damaged tissue in an objective and reproducible manner.

  11. CT and MRI imaging of the brain in MELAS syndrome

    International Nuclear Information System (INIS)

    MELAS syndrome (mitochondrial myopathy, encephalopathy, lactic acidosis, stroke-like episodes) is a rare, multisystem disorder which belongs to a group of mitochondrial metabolic diseases. As other diseases in this group, it is inherited in the maternal line. In this report, we discussed a case of a 10-year-old girl with clinical and radiological picture of MELAS syndrome. We would like to describe characteristic radiological features of MELAS syndrome in CT, MRI and MR spectroscopy of the brain and differential diagnosis. The rarity of this disorder and the complexity of its clinical presentation make MELAS patients among the most difficult to diagnose. Brain imaging studies require a wide differential diagnosis, primarily to distinguish between MELAS and ischemic stroke. Particularly helpful are the MRI and MR spectroscopy techniques

  12. Pediatric brain stem gliomas: Comparison of evaluation by CT and MR imaging

    International Nuclear Information System (INIS)

    This study is a direct comparison of the role of CT and MR imaging in the pretreatment and posttreatment evaluation of pediatric brain-stem gliomas. Thirty-four patients with presumed brain-stem gliomas were imaged by both CT and MR over the past 53 months. Twenty-two males and 12 females ranged in age from 3 to 17 years. Fifteen patients had tumor confirmed by biopsy. Thirteen children with nonneoplastic brain-stem lesions were imaged. MR proved superior to CT in both the pretreatment and posttreatment evaluation of patients with brain-stem gliomas. Pathologic correlation to the images is made in selected cases

  13. Three modality image registration of brain SPECT/CT and MR images for quantitative analysis of dopamine transporter imaging

    Science.gov (United States)

    Yamaguchi, Yuzuho; Takeda, Yuta; Hara, Takeshi; Zhou, Xiangrong; Matsusako, Masaki; Tanaka, Yuki; Hosoya, Kazuhiko; Nihei, Tsutomu; Katafuchi, Tetsuro; Fujita, Hiroshi

    2016-03-01

    Important features in Parkinson's disease (PD) are degenerations and losses of dopamine neurons in corpus striatum. 123I-FP-CIT can visualize activities of the dopamine neurons. The activity radio of background to corpus striatum is used for diagnosis of PD and Dementia with Lewy Bodies (DLB). The specific activity can be observed in the corpus striatum on SPECT images, but the location and the shape of the corpus striatum on SPECT images only are often lost because of the low uptake. In contrast, MR images can visualize the locations of the corpus striatum. The purpose of this study was to realize a quantitative image analysis for the SPECT images by using image registration technique with brain MR images that can determine the region of corpus striatum. In this study, the image fusion technique was used to fuse SPECT and MR images by intervening CT image taken by SPECT/CT. The mutual information (MI) for image registration between CT and MR images was used for the registration. Six SPECT/CT and four MR scans of phantom materials are taken by changing the direction. As the results of the image registrations, 16 of 24 combinations were registered within 1.3mm. By applying the approach to 32 clinical SPECT/CT and MR cases, all of the cases were registered within 0.86mm. In conclusions, our registration method has a potential in superimposing MR images on SPECT images.

  14. Cortical region of interest definition on SPECT brain images using X-ray CT registration

    International Nuclear Information System (INIS)

    We present a method for brain single photon emission computed tomography (SPECT) analysis based on individual registration of anatomical (CT) and functional (133Xe regional cerebral blood flow) images and on the definition of three-dimensional functional regions of interest. Registration of CT and SPECT is performed through adjustment of CT-defined cortex limits to the SPECT image. Regions are defined by sectioning a cortical ribbon on the CT images, copied over the SPECT images and pooled through slices to give 3D cortical regions of interest. The proposed method shows good intra- and interobserver reproducibility (regional intraclass correlation coefficient ≅0.98), and good accuracy in terms of repositioning (≅3.5 mm) as compared to the SPECT image resolution (14 mm). The method should be particularly useful for analysing SPECT studies when variations in brain anatomy (normal or abnormal) must be accounted for. (orig.)

  15. Quadratic Program Optimization using Support Vector Machine for CT Brain Image Classification

    Directory of Open Access Journals (Sweden)

    J.Umamaheswari

    2012-07-01

    Full Text Available In this paper, an efficient Computer Tomography (CT image classification using Support Vector Machine (SVM with optimized quadratic programming methodology is proposed. Due to manual interpretation of brain images based on visual examination by radiologist/physician that cause incorrect diagnosis, when a large number of CT images are analyzed. To avoid the human error, an automated optimized classification system is proposed for abnormal CT image identification. This is an automated system for content based image retrieval with better classifier accuracy and prediction time. SVM classifier can accurately train up the datas as normal and abnormal brains interpreted manually by the user. The system can retrieve more number of images present in the query data base. The proposed classifier is analyzed with existing Sequential Minimal Optimization (SMO and K Nearest Neighbour classifier KNN. From the experimental analysis, the proposed classifier outperforms all other classifier taken for examination.

  16. Automatic registration of CT and MR brain images using correlation of geometrical features

    International Nuclear Information System (INIS)

    This paper describes an automated approach to register CT and MR brain images. Differential operators in scale space are applied to each type of image data, so as to produce feature images depicting ''ridgeness''. The resulting CT and MR feature images show similarities which can be used for matching. No segmentation is needed and the method is devoid of human interaction. The matching is accomplished by hierarchical correlation techniques. Results of 2-D and 3-D matching experiments are presented. The correlation function ensures an accurate match even if the scanned volumes to be matched do not completely overlap, or if some of the features in the images are not similar

  17. Automatic CT Brain Image Segmentation Using Two Level Multiresolution Mixture Model of EM

    Science.gov (United States)

    Jiji, G. Wiselin; Dehmeshki, Jamshid

    2014-04-01

    Tissue classification in computed tomography (CT) brain images is an important issue in the analysis of several brain dementias. A combination of different approaches for the segmentation of brain images is presented in this paper. A multi resolution algorithm is proposed along with scaled versions using Gaussian filter and wavelet analysis that extends expectation maximization (EM) algorithm. It is found that it is less sensitive to noise and got more accurate image segmentation than traditional EM. Moreover the algorithm has been applied on 20 sets of CT of the human brain and compared with other works. The segmentation results show the advantages of the proposed work have achieved more promising results and the results have been tested with Doctors.

  18. Image quality in CT perfusion imaging of the brain. The role of iodine concentration

    Energy Technology Data Exchange (ETDEWEB)

    Koenig, Matthias; Bueltmann, Eva; Bode-Schnurbus, Lucas; Koenen, Dirk; Mielke, Eckhart; Heuser, Lothar [Knappschaftskrankenhaus Langendreer, Department of Diagnostic and Interventional Radiology and Nuclear Medicine, Ruhr-University Bochum, Bochum (Germany)

    2007-01-15

    The purpose of this study was to evaluate the impact of various iodine contrast concentrations on image quality in computed tomography (CT) perfusion studies. Twenty-one patients with suspicion of cerebral ischemia underwent perfusion CT using two different iodine contrast concentrations: 11 patients received iomeprol 300 (iodine concentration: 300 mg/ml) while ten received the same volume of iomeprol 400 (iodine concentration: 400 mg/ml). Scan parameters were kept constant for both groups. Maps of cerebral blood flow (CBF), cerebral blood volume (CBV), and time to peak (TTP) were calculated from two adjacent slices. Quantitative comparisons were based on measurements of the maximum enhancement [Hounsfield units (HU)] and signal-to-noise index (SNI) on CBF, CBV, and TTP images. Determinations of grey-to-white-matter delineation for each iodine concentration were performed by two blinded readers. Only data from the non-ischemic hemispheres were considered. Both maximum enhancement and SNI values were higher after iomeprol 400, resulting in significantly better image quality in areas of low perfusion. No noteworthy differences were found for normal values of CBF, CBV, and TTP. Qualitative assessment of grey/white matter contrast on CBF and CBV maps revealed better performance for iomeprol 400. For brain perfusion studies, highly concentrated contrast media such as iomeprol 400 is superior to iomeprol 300. (orig.)

  19. Impact of metal artefacts due to EEG electrodes in brain PET/CT imaging

    International Nuclear Information System (INIS)

    The goal of this study is to investigate the impact of electroencephalogram (EEG) electrodes on the visual quality and quantification of 18F-FDG PET images in neurological PET/CT examinations. For this purpose, the scans of 20 epilepsy patients with EEG monitoring were used. The CT data were reconstructed with filtered backprojection (FBP) and with a metal artefact reduction (MAR) algorithm. Both data sets were used for CT-based attenuation correction (AC) of the PET data. Also, a calculated AC (CALC) technique was considered. A volume of interest (VOI)-based analysis and a voxel-based quantitative analysis were performed to compare the different AC methods. Images were also evaluated visually by two observers. It was shown with simulations and phantom measurements that from the considered AC methods, the MAR-AC can be used as the reference in this setting. The visual assessment of PET images showed local hot spots outside the brain corresponding to the locations of the electrodes when using FBP-AC. In the brain, no abnormalities were observed. The quantitative analysis showed a very good correlation between PET-FBP-AC and PET-MAR-AC, with a statistically significant positive bias in the PET-FBP-AC images of about 5-7% in most brain voxels. There was also good correlation between PET-CALC-AC and PET-MAR-AC, but in the PET-CALC-AC images, regions with both a significant positive and negative bias were observed. EEG electrodes give rise to local hot spots outside the brain and a positive quantification bias in the brain. However, when diagnosis is made by mere visual assessment, the presence of EEG electrodes does not seem to alter the diagnosis. When quantification is performed, the bias becomes an issue especially when comparing brain images with and without EEG monitoring

  20. Acupuncture of Weizhong (BL 40) and Zusanli (ST 36) on the study of brain function by PET/CT imaging

    International Nuclear Information System (INIS)

    Objective: To explore the correlation between acupuncture of the points and certain functional areas of brain by PET/CT imaging. Methods: Twelve healthy volunteers were acupunctured separately in the point Weizhong (BL 40, right leg) and Zusanli(ST 36, right leg), and 5 consecutive PET/CT images were taken, statistical parameter map (SPM) paired t-test was analyzed between the different activated brain PET/CT imagings. Results: Changes of PET/CT imaging were found in acupuncture of the point Weizhong (BL 40) and Zusanli(ST 36) in 12 healthy volunteers. High metabolic areas were demonstrated in multiple brain regions, the data of two groups had significant difference between 2 points (t>4.03, P< 0.01). Conclusion: Acupuncturing the different point resulted activation of the glucose metabolism in different brain areas. (authors)

  1. Evaluation of electrode position in deep brain stimulation by image fusion (MRI and CT)

    International Nuclear Information System (INIS)

    Imaging has an essential role in the evaluation of correct positioning of electrodes implanted for deep brain stimulation (DBS). Although MRI offers superior anatomic visualization of target sites, there are safety concerns in patients with implanted material; imaging guidelines are inconsistent and vary. The fusion of postoperative CT with preoperative MRI images can be an alternative for the assessment of electrode positioning. The purpose of this study was to assess the accuracy of measurements realized on fused images (acquired without a stereotactic frame) using a manufacturer-provided software. Data from 23 Parkinson's disease patients who underwent bilateral electrode placement for subthalamic nucleus (STN) DBS were acquired. Preoperative high-resolution T2-weighted sequences at 3 T, and postoperative CT series were fused using a commercially available software. Electrode tip position was measured on the obtained images in three directions (in relation to the midline, the AC-PC line and an AC-PC line orthogonal, respectively) and assessed in relation to measures realized on postoperative 3D T1 images acquired at 1.5 T. Mean differences between measures carried out on fused images and on postoperative MRI lay between 0.17 and 0.97 mm. Fusion of CT and MRI images provides a safe and fast technique for postoperative assessment of electrode position in DBS. (orig.)

  2. Evaluation of electrode position in deep brain stimulation by image fusion (MRI and CT)

    Energy Technology Data Exchange (ETDEWEB)

    Barnaure, I.; Lovblad, K.O.; Vargas, M.I. [Geneva University Hospital, Department of Neuroradiology, Geneva 14 (Switzerland); Pollak, P.; Horvath, J.; Boex, C.; Burkhard, P. [Geneva University Hospital, Department of Neurology, Geneva (Switzerland); Momjian, S. [Geneva University Hospital, Department of Neurosurgery, Geneva (Switzerland); Remuinan, J. [Geneva University Hospital, Department of Radiology, Geneva (Switzerland)

    2015-09-15

    Imaging has an essential role in the evaluation of correct positioning of electrodes implanted for deep brain stimulation (DBS). Although MRI offers superior anatomic visualization of target sites, there are safety concerns in patients with implanted material; imaging guidelines are inconsistent and vary. The fusion of postoperative CT with preoperative MRI images can be an alternative for the assessment of electrode positioning. The purpose of this study was to assess the accuracy of measurements realized on fused images (acquired without a stereotactic frame) using a manufacturer-provided software. Data from 23 Parkinson's disease patients who underwent bilateral electrode placement for subthalamic nucleus (STN) DBS were acquired. Preoperative high-resolution T2-weighted sequences at 3 T, and postoperative CT series were fused using a commercially available software. Electrode tip position was measured on the obtained images in three directions (in relation to the midline, the AC-PC line and an AC-PC line orthogonal, respectively) and assessed in relation to measures realized on postoperative 3D T1 images acquired at 1.5 T. Mean differences between measures carried out on fused images and on postoperative MRI lay between 0.17 and 0.97 mm. Fusion of CT and MRI images provides a safe and fast technique for postoperative assessment of electrode position in DBS. (orig.)

  3. The registration accuracy analysis of different CT-MRI imaging fusion method in brain tumor

    International Nuclear Information System (INIS)

    Objective: To find an effective CT-MRI image fusion protocol in brain tumor by analyzing the registration accuracy of different methods. Methods: The simulation CT scan and MRI T1 WI imaging of 10 brain tumor patients obtained with same position were registered by Tris-Axes landmark ,Tris-Axes landmark + manual adjustment, mutual information and mutual information + manual adjustment method. The clinical tumor volume (CTV) were contoured on both CT and MRI images respectively. The accuracy of image fusion was assessed by the mean distance of five bone markers (d1-5), central position of CTV (dCTV) the percentage of CTV overlap (PCT-MRI) between CT and MRI images. The difference between different methods was analyzed by Freedman M non-parameter test. Results: The difference of the means d1-5 between the Tris-Axes landmark,Tris-Axes landmark plus manual adjustment,mutual information and mutual information plus manual adjustment methods were 0.28 cm ±0.12 cm, 0.15 cm ±0.02 cm, 0.25 cm± 0.19 cm, 0.10 cm ± 0.06 cm, (M = 14.41, P = 0.002). the means dCTV were 0.59 cm ± 0.28 cm, 0.60 cm± 0.32 cm, 0.58 cm ± 0.39 cm, 0.42 cm± 0.30 cm (M = 9.72, P = 0.021), the means PCT-MRI were 0.69% ±0.18%, 0.68% ±0.16%, 0.66% ±0.17%, 0.74% ±0.14% (M =14.82, P=0.002), respectively. Conclusions: Mutual information plus manual adjustment registration method was the preferable fusion method for brain tumor patients. (authors)

  4. A Case of Primary Colon Carcinoma Demonstrated by FDG PET/CT Imaging After Detection of a Solitary Brain Metastasis

    Directory of Open Access Journals (Sweden)

    Seval Erhamamcı

    2015-06-01

    Full Text Available The detection of brain metastases as the initial manifestation of colorectal carcinoma without liver or lung involvement is extremely rare. Herein we present a case of a 52-year-old male patient with an unusual presentation of colon cancer, with primary lesions demonstrated by fluorine-18-labeled fluorodeoxyglucose (FDG Positron-emission tomography/computed tomography (PET/CT after detection of a solitary brain metastasis. Brain CT images revealed a brain tumor. Histopathologic evaluation indicated metastatic poorly differentiated adenocarcinoma, while his physical examination was normal. The PET/ CT revealed abnormal intense FDG uptake in the right parietal region and in descending colon, with no other abnormal FDG uptake elsewhere in the body. The histopathologic diagnosis of the descending colon lesion revealed moderately differentiated adenocarcinoma. This case indicates that FDG PET/CT imaging may have a positive impact on the evaluation of patients with brain metastasis from an unknown primary.

  5. Analysis of CT Brain Images using Radial Basis Function Neural Network

    Directory of Open Access Journals (Sweden)

    T. Joshva Devadas

    2012-07-01

    Full Text Available Medical image processing and analysis is the tool to assist radiologists in the diagnosis process to obtain a more accurate and faster diagnosis. In this work, we have developed a neural network to classify the computer tomography (CT brain tumor image for automatic diagnosis. This system is divided into four steps namely enhancement, segmentation, feature extraction and classification. In the first phase, an edge-based selective median filter is used to improve the visibility of the loss of the gray-white matter interface in CT brain tumor images. Second phase uses a modified version of shift genetic algorithm for the segmentation. Next phase extracts the textural features using statistical texture analysis method. These features are fed into classifiers like BPN, Fuzzy k-NN, and radial basis function network. The performances of these classifiers are analyzed in the final phase with receiver operating characteristic and precision-recall curve. The result shows that the CAD system is only to develop the tool for brain tumor and proposed method is very accurate and computationally more efficient and less time consuming.

  6. CT and MR imaging evaluation of the inherited and prenatally acquired migrational disorders of the brain

    International Nuclear Information System (INIS)

    The migrational disorders are a rare group of congenital malformations of the brain seen in children. They are primarily cortical and gray matter abnormalities. Forty patients, divided into two groups, were studied. In one group were patients with the classic migrational lesions of lissencephaly, pachygyria, schizencephaly, heterotopia, and polymicrogyria in which the underlying cause is genetic, chromosomal, or unknown. In the second group were patients with lesions caused by a prenatally acquired infection (toxoplasmosis or cytomegalic virus) or a metabolic abnormality. The CT and MR imaging findings in these two groups are discussed

  7. High-fidelity artifact correction for cone-beam CT imaging of the brain

    Science.gov (United States)

    Sisniega, A.; Zbijewski, W.; Xu, J.; Dang, H.; Stayman, J. W.; Yorkston, J.; Aygun, N.; Koliatsos, V.; Siewerdsen, J. H.

    2015-02-01

    CT is the frontline imaging modality for diagnosis of acute traumatic brain injury (TBI), involving the detection of fresh blood in the brain (contrast of 30-50 HU, detail size down to 1 mm) in a non-contrast-enhanced exam. A dedicated point-of-care imaging system based on cone-beam CT (CBCT) could benefit early detection of TBI and improve direction to appropriate therapy. However, flat-panel detector (FPD) CBCT is challenged by artifacts that degrade contrast resolution and limit application in soft-tissue imaging. We present and evaluate a fairly comprehensive framework for artifact correction to enable soft-tissue brain imaging with FPD CBCT. The framework includes a fast Monte Carlo (MC)-based scatter estimation method complemented by corrections for detector lag, veiling glare, and beam hardening. The fast MC scatter estimation combines GPU acceleration, variance reduction, and simulation with a low number of photon histories and reduced number of projection angles (sparse MC) augmented by kernel de-noising to yield a runtime of ~4 min per scan. Scatter correction is combined with two-pass beam hardening correction. Detector lag correction is based on temporal deconvolution of the measured lag response function. The effects of detector veiling glare are reduced by deconvolution of the glare response function representing the long range tails of the detector point-spread function. The performance of the correction framework is quantified in experiments using a realistic head phantom on a testbench for FPD CBCT. Uncorrected reconstructions were non-diagnostic for soft-tissue imaging tasks in the brain. After processing with the artifact correction framework, image uniformity was substantially improved, and artifacts were reduced to a level that enabled visualization of ~3 mm simulated bleeds throughout the brain. Non-uniformity (cupping) was reduced by a factor of 5, and contrast of simulated bleeds was improved from ~7 to 49.7 HU, in good agreement

  8. High-fidelity artifact correction for cone-beam CT imaging of the brain

    International Nuclear Information System (INIS)

    CT is the frontline imaging modality for diagnosis of acute traumatic brain injury (TBI), involving the detection of fresh blood in the brain (contrast of 30–50 HU, detail size down to 1 mm) in a non-contrast-enhanced exam. A dedicated point-of-care imaging system based on cone-beam CT (CBCT) could benefit early detection of TBI and improve direction to appropriate therapy. However, flat-panel detector (FPD) CBCT is challenged by artifacts that degrade contrast resolution and limit application in soft-tissue imaging. We present and evaluate a fairly comprehensive framework for artifact correction to enable soft-tissue brain imaging with FPD CBCT. The framework includes a fast Monte Carlo (MC)-based scatter estimation method complemented by corrections for detector lag, veiling glare, and beam hardening. The fast MC scatter estimation combines GPU acceleration, variance reduction, and simulation with a low number of photon histories and reduced number of projection angles (sparse MC) augmented by kernel de-noising to yield a runtime of ∼4 min per scan. Scatter correction is combined with two-pass beam hardening correction. Detector lag correction is based on temporal deconvolution of the measured lag response function. The effects of detector veiling glare are reduced by deconvolution of the glare response function representing the long range tails of the detector point-spread function. The performance of the correction framework is quantified in experiments using a realistic head phantom on a testbench for FPD CBCT. Uncorrected reconstructions were non-diagnostic for soft-tissue imaging tasks in the brain. After processing with the artifact correction framework, image uniformity was substantially improved, and artifacts were reduced to a level that enabled visualization of ∼3 mm simulated bleeds throughout the brain. Non-uniformity (cupping) was reduced by a factor of 5, and contrast of simulated bleeds was improved from ∼7 to 49.7 HU, in good

  9. Analysis of CT Brain Images using Radial Basis Function Neural Network

    Directory of Open Access Journals (Sweden)

    T. Joshva Devadas

    2012-07-01

    Full Text Available Medical image processing and analysis is the tool to assist radiologists in the diagnosis process to obtain a moreaccurate and faster diagnosis. In this work, we have developed a neural network to classify the computer tomography(CT brain tumor image for automatic diagnosis. This system is divided into four steps namely enhancement, segmentation, feature extraction and classification. In the first phase, an edge-based selective median filter is usedto improve the visibility of the loss of the gray-white matter interface in CT brain tumor images. Second phaseuses a modified version of shift genetic algorithm for the segmentation. Next phase extracts the textural featuresusing statistical texture analysis method. These features are fed into classifiers like BPN, Fuzzy k-NN, and radialbasis function network. The performances of these classifiers are analyzed in the final phase with receiver operating characteristic and precision-recall curve. The result shows that the CAD system is only to develop the tool for braintumor and proposed method is very accurate and computationally more efficient and less time consuming.Defence Science Journal, 2012, 62(4, pp.212-218, DOI:http://dx.doi.org/10.14429/dsj.62.1830

  10. Inclusion of brain in FDG PET/CT scanning techniques in cancer patients: Does it obviate the need for dedicated brain imaging?

    International Nuclear Information System (INIS)

    Metastases to the brain can affect about 10-20% cancer patients. Rising incidence of brain metastases in recent years is related to improved survival rates as a result of advances in cancer therapy and development of more sensitive diagnostic imaging techniques. In patients with extracranial malignancies detection of brain metastases is very important in deciding further diagnostic procedures, planning therapeutic strategies and also to ascertain prognosis. Computerized tomography (CT) and magnetic resonance imaging (MRI) are the modalities which have been traditionally used to assess metastatic disease to the central nervous system. It is generally accepted that MRI (contrast enhanced) is superior to CT scan (contrast enhanced) in the diagnosis of brain metastases. An inherently better soft tissue contrast resolution, stronger contrast enhancement, lack of bone artifacts and partial volume effects and direct multiplanar imaging enables MRI to pick up smaller sized as well as more number of metastases than a CT scan

  11. Targeting of deep-brain structures in nonhuman primates using MR and CT Images

    Science.gov (United States)

    Chen, Antong; Hines, Catherine; Dogdas, Belma; Bone, Ashleigh; Lodge, Kenneth; O'Malley, Stacey; Connolly, Brett; Winkelmann, Christopher T.; Bagchi, Ansuman; Lubbers, Laura S.; Uslaner, Jason M.; Johnson, Colena; Renger, John; Zariwala, Hatim A.

    2015-03-01

    In vivo gene delivery in central nervous systems of nonhuman primates (NHP) is an important approach for gene therapy and animal model development of human disease. To achieve a more accurate delivery of genetic probes, precise stereotactic targeting of brain structures is required. However, even with assistance from multi-modality 3D imaging techniques (e.g. MR and CT), the precision of targeting is often challenging due to difficulties in identification of deep brain structures, e.g. the striatum which consists of multiple substructures, and the nucleus basalis of meynert (NBM), which often lack clear boundaries to supporting anatomical landmarks. Here we demonstrate a 3D-image-based intracranial stereotactic approach applied toward reproducible intracranial targeting of bilateral NBM and striatum of rhesus. For the targeting we discuss the feasibility of an atlas-based automatic approach. Delineated originally on a high resolution 3D histology-MR atlas set, the NBM and the striatum could be located on the MR image of a rhesus subject through affine and nonrigid registrations. The atlas-based targeting of NBM was compared with the targeting conducted manually by an experienced neuroscientist. Based on the targeting, the trajectories and entry points for delivering the genetic probes to the targets could be established on the CT images of the subject after rigid registration. The accuracy of the targeting was assessed quantitatively by comparison between NBM locations obtained automatically and manually, and finally demonstrated qualitatively via post mortem analysis of slices that had been labelled via Evan Blue infusion and immunohistochemistry.

  12. Radiation dose reduction in CT of the brain: can advanced noise filtering compensate for loss of image quality?

    International Nuclear Information System (INIS)

    Background: Computed tomography (CT) of the brain is performed with high local doses due to high demands on low contrast resolution. Advanced algorithms for noise reduction might be able to preserve critical image information when reducing radiation dose. Purpose: To evaluate the effect of advanced noise filtering on image quality in brain CT acquired with reduced radiation dose. Material and Methods: Thirty patients referred for non-enhanced CT of the brain were examined with two helical protocols: normal dose (ND, CTDIvol 57 mGy) and low dose (LD, CTDIvol 40 mGy) implying a 30% radiation dose reduction. Images from the LD examinations were also post processed with a noise reduction software with non-linear filters (SharpView CT), creating filtered low dose images (FLD) for each patient. The three image stacks for each patient were presented side by side in randomized order. Five radiologists, blinded for dose level and filtering, ranked these three axial image stacks (ND, LD, FLD) as best to poorest (1 to 3) regarding three image quality criteria. Measurements of mean Hounsfield units (HU) and standard deviation (SD) of the HU were calculated for large region of interest in the centrum semiovale as a measure for noise. Results: Ranking results in pooled data showed that the advanced noise filtering significantly improved the image quality in FLD as compared to LD images for all tested criteria. No significant differences in image quality were found between ND examinations and FLD. However, there was a notable inter-reader spread of the ranking. SD values were 15% higher for LD as compared to ND and FLD. Conclusion: The advanced noise filtering clearly improves image quality of CT examinations of the brain. This effect can be used to significantly lower radiation dose.

  13. The preliminary study of CT cerebral perfusion imaging on the brain injury of the high + Gx in Rhesus

    International Nuclear Information System (INIS)

    Objective: To exp lore the diagnostic value of CT cerebral perfusion imaging on the brain injury of the high + Gx in Rhesus. Methods: Seven healthy male adult Rhesus were randomly divided into control group and + 15 Gx group. The + 15 Gx group underwent parabolic G curve in animal centrifuge. The animals were all examined by CT cerebral perfusion before + Gx exposure, 2 h, 24 h, and 1 week after + Gx exposure. The results were compared with pathologic examination. Results: 2 h and 24 h after + 15 Gx exposure, brain ischemia was showed on CT cerebral perfusion imaging. After 1 week, the brain ischemia was almost recovered to normal. Mild ischemic atrophy was observed in pyramidal neurons in cerebral cortex by light microscopy. Electron microscopic observation showed chromatin marginating and mitochondria cristae blurring in pyramidal cells after + Gx overload. Conclusion: High G from simulating spaceship emergency return can cause ischemic injuries of the brain in Rhesus, and CT brain perfusion imaging can provide valuable diagnostic information. (authors)

  14. Acute neuromedical and neurosurgical admissions: Standard and ultrafast MR imaging of the brain compared with cranial CT

    International Nuclear Information System (INIS)

    Purpose: To evaluate the role of standard and ultrafast MR brain imaging and compare the information with CT. Material and Methods: This was a prospective study of 114 patients with acute neurological symptoms and signs. CT brain examinations consisted of axial non-enhanced images. MR imaging consisted of standard spin-echo/fast spin-echo sequences and a series of rapid techniques including echoplanar and single shot fast spin-echo sequences. Results: Using standard MR methods, 41% of the patients had all five sequences of good technical quality, while using ultrafast methods 81% of the patients had good technical quality examinations in all five sequences. In 3% of the cases, ischaemic stroke was incorrectly reported on CT. In 24% of the cases, MR gave extra diagnostic information not reported on CT and in a further 8%, one neuro radiologist reported the abnormality in agreement with the MR, whilst the other neuro radiologist reported the CT as normal. In 2 cases, subarachnoid haemorrhage was missed on MR. Subarachnoid haemorrhage was not shown on the ultrafast sequences. Conclusion: MR can be used to image acute neurological admissions with a high success rate, particularly using ultrafast methods. In many cases, MR provided extra information of direct clinical relevance not shown on CT

  15. Clinical neuroanatomy and diagnostic imaging and evaluation of the brain. MRI and CT atlas. 3. new rev. and enl. ed.

    International Nuclear Information System (INIS)

    New features of this 3rd German edition are: - Number of the MR and CT images almost doubled, all pictures now in large format, displaying much more brain structures. - New knowledge and insight incorporated in the text and pictures. (orig./CB)

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

    International Nuclear Information System (INIS)

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

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

    Energy Technology Data Exchange (ETDEWEB)

    Seiki, Yoshikatsu; Shibata, Iekado; Mito, Toshiaki; Sugo, Nobuo [Toho Univ., Tokyo (Japan). School of Medicine

    2000-09-01

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

  18. A Novel Procedure for Rapid Imaging of Adult Mouse Brains with MicroCT Using Iodine-Based Contrast.

    Directory of Open Access Journals (Sweden)

    Ryan Anderson

    Full Text Available High-resolution Magnetic Resonance Imaging (MRI has been the primary modality for obtaining 3D cross-sectional anatomical information in animals for soft tissue, particularly brain. However, costs associated with MRI can be considerably high for large phenotypic screens for gross differences in the structure of the brain due to pathology and/or experimental manipulations. MicroCT (mCT, especially benchtop mCT, is becoming a common laboratory equipment with throughput rates equal or faster than any form of high-resolution MRI at lower costs. Here we explore adapting previously developed contrast based mCT to image adult mouse brains in-situ. We show that 2% weight per volume (w/v iodine-potassium iodide solution can be successfully used to image adult mouse brains within 48 hours post-mortem when a structural support matrix is used. We demonstrate that hydrogel can be effectively used as a perfusant which limits the tissue shrinkage due to iodine.

  19. Automated ventricular systems segmentation in brain CT images by combining low-level segmentation and high-level template matching

    Directory of Open Access Journals (Sweden)

    Ward Kevin R

    2009-11-01

    Full Text Available Abstract Background Accurate analysis of CT brain scans is vital for diagnosis and treatment of Traumatic Brain Injuries (TBI. Automatic processing of these CT brain scans could speed up the decision making process, lower the cost of healthcare, and reduce the chance of human error. In this paper, we focus on automatic processing of CT brain images to segment and identify the ventricular systems. The segmentation of ventricles provides quantitative measures on the changes of ventricles in the brain that form vital diagnosis information. Methods First all CT slices are aligned by detecting the ideal midlines in all images. The initial estimation of the ideal midline of the brain is found based on skull symmetry and then the initial estimate is further refined using detected anatomical features. Then a two-step method is used for ventricle segmentation. First a low-level segmentation on each pixel is applied on the CT images. For this step, both Iterated Conditional Mode (ICM and Maximum A Posteriori Spatial Probability (MASP are evaluated and compared. The second step applies template matching algorithm to identify objects in the initial low-level segmentation as ventricles. Experiments for ventricle segmentation are conducted using a relatively large CT dataset containing mild and severe TBI cases. Results Experiments show that the acceptable rate of the ideal midline detection is over 95%. Two measurements are defined to evaluate ventricle recognition results. The first measure is a sensitivity-like measure and the second is a false positive-like measure. For the first measurement, the rate is 100% indicating that all ventricles are identified in all slices. The false positives-like measurement is 8.59%. We also point out the similarities and differences between ICM and MASP algorithms through both mathematically relationships and segmentation results on CT images. Conclusion The experiments show the reliability of the proposed algorithms. The

  20. Brain tumor delineation based on CT and MR imaging. Implications for radiotherapy treatment planning

    NARCIS (Netherlands)

    Heesters, M A; Wijrdeman, H K; Struikmans, H; Witkamp, T; Moerland, M A

    1993-01-01

    This paper deals with the impact MRI may have on radiotherapy treatment planning of brain tumors. The authors analyzed differences in size and position of treatment fields as indicated by three observers (two radiotherapists and one neuroradiologist) using CT or MR based radiotherapy planning proced

  1. Adverse effects of brain irradiation correlated with MR and CT imaging

    International Nuclear Information System (INIS)

    Forty-one patients treated for primary malignancies of the brain at the University of Rochester Cancer Center since 1970 were assessed for adverse effects of irradiation clinically, and by computerized tomography (CT) and magnetic resonance (MR) imaging. At diagnosis, patients ranged in age from 1-65 years (median 19 years) and the most common tumor (in 30) was astrocytoma. Radiation doses ranged from 45 to 81.3 Gy (median 56.8 Gy). White matter changes visible on MR were graded on a scale of 1-4, with grades 1-2 known to occur in some normal patients. Areas of increased signal intensity not associated with the tumor or surgery were visible in all patients (gr 1 = 37%, gr 2 = 32%, gr 3 = 17%, gr 4 = 15%) whereas only 35% had regions of abnormality (hypodensity) on CT. Sulci enlargement and ventricular abnormalities (asymmetry or dilatation) were present in approximately 50% of patients by each technique. Higher grade MR lesions were associated with radiation to large volumes and high doses. For the 36 patients treated with 1.5-2.0 Gy daily fractions, the mean radiation dose by grade was as follows: gr 1 = 55.1 Gy, gr 2 = 58.8 Gy, gr 3 = 60.0 Gy, gr 4 = 63.5 Gy. All 5 patients treated on a hyperfractionated schedule had gr 1-2 changes despite receiving greater than 70 Gy. Fifty percent of patients treated to the whole brain (+/- boost) had gr 3-4 changes, compared with 14% treated with local fields (peak dose regions similar in both groups). Among the children (less than or equal to 13 years), 20% had gr 3-4 changes compared with 56% of adults (excluding hyperfractionated patients). This finding may be due entirely or in part to the lower radiation doses used for children (mean 54.4 Gy vs. 63.7 Gy in adults). Clinical abnormalities attributable to irradiation included an impairment in mental functioning in 7 adults, and learning disabilities in 5 children

  2. CT-based attenuation and scatter correction compared with uniform attenuation correction in brain perfusion SPECT imaging for dementia

    Science.gov (United States)

    Gillen, Rebecca; Firbank, Michael J.; Lloyd, Jim; O'Brien, John T.

    2015-09-01

    This study investigated if the appearance and diagnostic accuracy of HMPAO brain perfusion SPECT images could be improved by using CT-based attenuation and scatter correction compared with the uniform attenuation correction method. A cohort of subjects who were clinically categorized as Alzheimer’s Disease (n=38 ), Dementia with Lewy Bodies (n=29 ) or healthy normal controls (n=30 ), underwent SPECT imaging with Tc-99m HMPAO and a separate CT scan. The SPECT images were processed using: (a) correction map derived from the subject’s CT scan or (b) the Chang uniform approximation for correction or (c) no attenuation correction. Images were visually inspected. The ratios between key regions of interest known to be affected or spared in each condition were calculated for each correction method, and the differences between these ratios were evaluated. The images produced using the different corrections were noted to be visually different. However, ROI analysis found similar statistically significant differences between control and dementia groups and between AD and DLB groups regardless of the correction map used. We did not identify an improvement in diagnostic accuracy in images which were corrected using CT-based attenuation and scatter correction, compared with those corrected using a uniform correction map.

  3. 3D movement correction of CT brain perfusion image data of patients with acute ischemic stroke

    International Nuclear Information System (INIS)

    Head movement during CT brain perfusion (CTP) acquisition can deteriorate the accuracy of CTP analysis. Most CTP software packages can only correct in-plane movement and are limited to small ranges. The purpose of this study is to validate a novel 3D correction method for head movement during CTP acquisition. Thirty-five CTP datasets that were classified as defective due to head movement were included in this study. All CTP time frames were registered with non-contrast CT data using a 3D rigid registration method. Location and appearance of ischemic area in summary maps derived from original and registered CTP datasets were qualitative compared with follow-up non-contrast CT. A quality score (QS) of 0 to 3 was used to express the degree of agreement. Furthermore, experts compared the quality of both summary maps and assigned the improvement score (IS) of the CTP analysis, ranging from -2 (much worse) to 2 (much better). Summary maps generated from corrected CTP significantly agreed better with appearance of infarct on follow-up CT with mean QS 2.3 versus mean QS 1.8 for summary maps from original CTP (P = 0.024). In comparison to original CTP data, correction resulted in a quality improvement with average IS 0.8: 17 % worsened (IS = -2, -1), 20 % remained unchanged (IS = 0), and 63 % improved (IS = +1, +2). The proposed 3D movement correction improves the summary map quality for CTP datasets with severe head movement. (orig.)

  4. 3D movement correction of CT brain perfusion image data of patients with acute ischemic stroke

    Energy Technology Data Exchange (ETDEWEB)

    Fahmi, Fahmi [Academic Medical Center, Department of Biomedical Engineering and Physics, Amsterdam (Netherlands); University of Sumatera Utara, Department of Electrical Engineering, Medan (Indonesia); Marquering, Henk A.; Streekstra, Geert J. [Academic Medical Center, Department of Biomedical Engineering and Physics, Amsterdam (Netherlands); Academic Medical Center, Department of Radiology, Amsterdam (Netherlands); Borst, Jordi; Beenen, Ludo F.M.; Majoie, Charles B.L. [Academic Medical Center, Department of Radiology, Amsterdam (Netherlands); Niesten, Joris M.; Velthuis, Birgitta K. [University Medical Center Utrecht, Department of Radiology, Utrecht (Netherlands); VanBavel, Ed [Academic Medical Center, Department of Biomedical Engineering and Physics, Amsterdam (Netherlands); Collaboration: on behalf of the DUST study

    2014-06-15

    Head movement during CT brain perfusion (CTP) acquisition can deteriorate the accuracy of CTP analysis. Most CTP software packages can only correct in-plane movement and are limited to small ranges. The purpose of this study is to validate a novel 3D correction method for head movement during CTP acquisition. Thirty-five CTP datasets that were classified as defective due to head movement were included in this study. All CTP time frames were registered with non-contrast CT data using a 3D rigid registration method. Location and appearance of ischemic area in summary maps derived from original and registered CTP datasets were qualitative compared with follow-up non-contrast CT. A quality score (QS) of 0 to 3 was used to express the degree of agreement. Furthermore, experts compared the quality of both summary maps and assigned the improvement score (IS) of the CTP analysis, ranging from -2 (much worse) to 2 (much better). Summary maps generated from corrected CTP significantly agreed better with appearance of infarct on follow-up CT with mean QS 2.3 versus mean QS 1.8 for summary maps from original CTP (P = 0.024). In comparison to original CTP data, correction resulted in a quality improvement with average IS 0.8: 17 % worsened (IS = -2, -1), 20 % remained unchanged (IS = 0), and 63 % improved (IS = +1, +2). The proposed 3D movement correction improves the summary map quality for CTP datasets with severe head movement. (orig.)

  5. Left-right subtraction of brain CT

    International Nuclear Information System (INIS)

    A new image-processing method to obtain a left-right subtraction image of CT was designed for the automated detection of abnormalities in brain CT. An original CT image was divided in two by a centerline. Then the right half of the image was subtracted from the left half by calculating the absorption value of the pixels on the symmetrical positions against the centerline. The mean and the standard deviation of the absorption value of the pixels in the subtraction image were used as parameters for analysis, and the detectability of abnormal CT findings was evaluated in 100 cases - 50 cases each with normal and abnormal CT. The presence of abnormalities could be diagnosed with a sensitivity of 86 %, a specificity of 90 %, and an overall accuracy of 88 % when the borderline of these parameters between normal and abnormal CT was set at the mean + 2SD in the normal group. As a further analysis, the CT image was subdivided into several areas from a functional or anatomical viewpoint, such as cerebral vascular territories, and the left-right subtraction image of each area was obtained. The possibilities of diagnosing the location of an abnormality and of detecting smaller lesions with this method were shown. Left-right subtraction was considered to be a useful method for the detection of asymmetric abnormalities in the automated diagnosis of brain CT. (author)

  6. Quantitative Perfusion and Permeability Biomarkers in Brain Cancer from Tomographic CT and MR Images

    OpenAIRE

    Eilaghi, Armin; Yeung, Timothy; d’Esterre, Christopher; Bauman, Glenn; Yartsev, Slav; Easaw, Jay; Fainardi, Enrico; Lee, Ting-Yim; Frayne, Richard

    2016-01-01

    Dynamic contrast-enhanced perfusion and permeability imaging, using computed tomography and magnetic resonance systems, are important techniques for assessing the vascular supply and hemodynamics of healthy brain parenchyma and tumors. These techniques can measure blood flow, blood volume, and blood–brain barrier permeability surface area product and, thus, may provide information complementary to clinical and pathological assessments. These have been used as biomarkers to enhance the treatme...

  7. Advanced brain dopamine transporter imaging in mice using small-animal SPECT/CT

    OpenAIRE

    Pitkonen, Miia; Hippeläinen, Eero; Raki, Mari; Andressoo, Jaan-Olle; Urtti, Arto; Männistö, Pekka T.; Savolainen, Sauli; Saarma, Mart; Bergström, Kim

    2012-01-01

    Background Iodine-123-β-CIT, a single-photon emission computed tomography (SPECT) ligand for dopamine transporters (DATs), has been used for in vivo studies in humans, monkeys, and rats but has not yet been used extensively in mice. To validate the imaging and analysis methods for preclinical DAT imaging, wild-type healthy mice were scanned using 123I-β-CIT. Methods The pharmacokinetics and reliability of 123I-β-CIT in mice (n = 8) were studied with a multipinhole SPECT/CT camera after intrav...

  8. Brain imaging

    International Nuclear Information System (INIS)

    The techniques of brain imaging and results in perfusion studies and delayed images are outlined. An analysis of the advantages and disadvantages of the brain scan in a variety of common problems is discussed, especially as compared with other available procedures. Both nonneoplastic and neoplastic lesions are considered. (Auth/C.F.)

  9. PET/CT imaging of striatal dopamine transporters in a newborn piglet model of hypoxic-ischemic brain injury

    International Nuclear Information System (INIS)

    Objective: To investigate changes of striatal DAT following hypoxic ischemic (HI) brain injury in newborn piglets using 11C-N-2-carbomethoxy-3-(4-fluorophenyl)-tropane (CFT) PET/CT, and to evaluate the value of 11C-CFT PET/CT in brain injury. Methods: Newborn piglets with HI brain injury (n=20) were taken as a model group,and five piglets were used as a control group. Radioligand 11C-CFT (55.5-74.0 MBq) was injected through the jugular vein, and PET/CT imaging was performed to observe the changes of striatal DAT in newborn piglets. The ST/occipital lobe (OC) ratio was calculated. Model group was divided into 0-6 h, 20-24 h, 44-48 h and 68-72 h sub-groups after HI in accordance with the imaging time. The piglets were sacrificed immediately after 11C-CFT PET/CT scanning, and then the brains were removed for pathological analysis. Data analysis was performed with one-way analysis of variance and Pearson linear correlation analysis. Results: After intravenous injection of 11C-CFT, the radioactivity accumulation in cortical, striatum, and cerebellum was shown clearly in the control and model groups. The radioactivity accumulation was lower in the white matter. The radioactivity in cortical and cerebellum exhibited decreased with time, while the striatum was still clear. After HI, the ST/OC activity ratio in the striatum was initially increased, and the ratio of 0-6 h group (1.34 ± 0.04) was statistically significant compared with that of the control group (1.18 ± 0.06; F=4.658, P<0.05), followed by a gradual decrease. ST/OC ratios of other HI subgroups were 1.27 ±0.01, 1.27 ±0.10 and 1.18 ±0.05, respectively. There was a positive correlation between the number of DAT positive neurons ((13 ± 3), (13 ± 4), (8 ±3) and (4 ±4)/high power field) and 11C-CFT ST/OC activity ratios (r=0.844, P<0.05). Conclusion: 11C-CFT PET/CT study can accurately reflect the changes of DAT in the striatum, and the amount of DAT is related to the severity of the ischemic insult in a

  10. Evaluation of 10 mAs and low-contrast CT image optimization based on the multifractal spectrum in brain of infant

    International Nuclear Information System (INIS)

    Objective: To analyze scanned image optimization based on the multifractal soectrum and image fractal algorithm of 64-slice spiral CT in brain of infant. Methods: The image data of Toshiba Aquilion 64-slice CT scanning using 10 mAs were imported to image processing toolboxs of Matlab 7.1. The evaluation of multifractal spectrum and image denosing were performed, and compared with image quality of conventional low-dose CT using 50 mAs. Results: The low-contrast scanned image used 10 mAs is the valueless medical image because of serious noise. Image denoise based on the fractal model had superior characteristic of image detail preserving and better contrast-to-noise ratio(CNR). There existed a group difference in the score of image quality between the rude imaging noise and optimized image based on the multifractal spectrum algorithm, though the score was still significantly lower than the normal dosage scanned image (F=38.85, P<0.01). The group difference was also manifested the image quality of infants can achieve basically the request of clinical diagnosis by suitable model denoising algorithm. Conclusions: Image denoising based on the multifractal spectrum model can be used on the low-dose and low-contrast CT image optimization. It improved the CNR of the pathological region. The radiation dose of CT scanning in infants would be declined significantly by its further application in the future. (authors)

  11. Emergency CT brain: preliminary interpretation with a tablet device: image quality and diagnostic performance of the Apple iPad.

    LENUS (Irish Health Repository)

    Mc Laughlin, Patrick

    2012-04-01

    Tablet devices have recently been used in radiological image interpretation because they have a display resolution comparable to desktop LCD monitors. We identified a need to examine tablet display performance prior to their use in preliminary interpretation of radiological images. We compared the spatial and contrast resolution of a commercially available tablet display with a diagnostic grade 2 megapixel monochrome LCD using a contrast detail phantom. We also recorded reporting discrepancies, using the ACR RADPEER system, between preliminary interpretation of 100 emergency CT brain examinations on the tablet display and formal review on a diagnostic LCD. The iPad display performed inferiorly to the diagnostic monochrome display without the ability to zoom. When the software zoom function was enabled on the tablet device, comparable contrast detail phantom scores of 163 vs 165 points were achieved. No reporting discrepancies were encountered during the interpretation of 43 normal examinations and five cases of acute intracranial hemorrhage. There were seven RADPEER2 (understandable) misses when using the iPad display and 12 with the diagnostic LCD. Use of software zoom in the tablet device improved its contrast detail phantom score. The tablet allowed satisfactory identification of acute CT brain findings, but additional research will be required to examine the cause of "understandable" reporting discrepancies that occur when using tablet devices.

  12. Computer tomographic imaging and anatomic correlation of the human brain: A comparative atlas of thin CT-scan sections and correlated neuro-anatomic preparations

    International Nuclear Information System (INIS)

    It is of the greatest importance to the radiologist, the neurologist and the neurosurgeon to be able to localize topographically a pathological brain process on the CT scan as precisely as possible. For that purpose, the identification of as many anatomical structures as possible on the CT scan image are necessary and indispensable. In this atlas a great number of detailed anatomical data on frontal horizontal CT scan sections, each being only 2 mm thick, are indicated, e.g. the cortical gyri, the basal ganglia, details of the white matter, extracranial muscles and blood vessels, parts of the base and the vault of the skull, etc. The very precise topographical description of the numerous CT scan images was realized by the author by confrontation of these images with the corresponding anatomical sections of the same brain specimen, performed by an original technique

  13. Comparative studies of '18F-FDG PET/CT brain imaging and EEG in preoperative localization of temporal lobe epileptic focus

    International Nuclear Information System (INIS)

    Objective: To compare the value of 18F-FDG PET/CT brain imaging and EEG in preoperative localization of the epileptic focus at the temporal lobe. Methods: A total of 152 patients (108 males, 44 females, age ranged from 3 to 59 years old) with past history of temporal lobe epilepsy were included.All patients underwent 18F-FDG PET/CT brain imaging and long-range or video EEG, and 29 patients underwent intracranial electrode EEG due to the failure to localize the disease focus by non-invasive methods.Histopathologic findings after operative treatment were considered the gold standard for disease localization. All patients were followed up for at least six months after the operation. The accuracy of the 18F-FDG PET/CT brain imaging and long-range or video EEG examination were compared using χ2 test. Results: The accuracy of locating the epileptic focus was 80.92% (123/152) for 18F-FDG PET/CT brain imaging and 43.42% (66/152) for long-range or video EEG (χ2=22.72, P<0.01). The accuracy of locating the epileptic focus for the 29 cases with intracranial electrode EEG was 100%. Conclusions: Interictal 18F-FDG PET/CT brain imaging is a sensitive and effective method to locate the temporal lobe epileptic focus and is better than long-range or video EEG. The combination of 18F-FDG PET/CT brain imaging and intracranial electrode EEG examination can further improve the accuracy of locating the epileptic focus. (authors)

  14. SU-D-9A-04: Brain PET/CT Imaging On a Scanner with a Large Axial Field-Of-View

    International Nuclear Information System (INIS)

    Purpose: Large axial field-of-view (FOV) PET/CT scanners are valued for high sensitivity. Brain PET image quality may depend on the head position within the FOV. We investigated the precision of activity estimation for brain PET imaging when the brain was positioned at the end (END) and in the middle (CEN) of the FOV. The additional CT dose for the CEN position was recorded. Methods: An image quality (Jaszczak) phantom and a striatal phantom were filled with F-18 and positioned in END and CEN locations. For each phantom and each location, we acquired a ∼1-hr listmode PET, rebinned the data into 10 frames with equal number of coincidence events, and reconstructed each frame using an iterative algorithm. For the striatal phantom, END and CEN were compared by drawing on each image three regions of interest (ROI) in axially separated uniform areas. The standard deviation of the activity estimation within each ROI was averaged over the 10 images. The coefficient of variation (CV) for activity estimation was calculated at each position. Image quality was assessed by inspecting the resolution bar pattern in the Jaszczak phantom at two different head positions. Results: The CV was the lowest for ROIs near the center of the FOV. For slices near the end, not only was the CV highest, but also the resolution pattern was degraded. CTDIvol summarized in the dose report indicated that the CT dose was ∼ 10% higher for CEN as compared to END position. Conclusion: Positioning the brain in the middle of the FOV in a large FOV PET/CT scanner allows more precise measurement of tracer uptake and better image quality at the cost of increased CT dose. For the end location longer scan times may minimize image quality degradation without any additional CT dose

  15. Analysis of brain CT on 120 patients of human cysticercosis

    International Nuclear Information System (INIS)

    A study on brain CT was made in 120 patients of human cysticercosis, which is a rare disease in Japan and clinical symptoms and laboratory data for the diagnosis were also discussed. From the point of therapeutic view, we proposed a new differentiation on brain CT of human cysticercosis, which is divided into two groups according to the alve or dead parasite. Furthermore, we proposed a new type named multiple large and small cysts type on brain CT. The idea of diagnostic standard was made integrating brain CT image, clinical symptoms and labolatory data. (author)

  16. Analysis of brain CT on 120 patients of human cysticercosis

    Energy Technology Data Exchange (ETDEWEB)

    Ma, J.; To, R.; Ri, T.; Ra, S. (Jiamusi Medical Coll. (China)); Inomata, Taiten; Ogawa, Yasuhiro; Maeda, Tomoo

    1990-08-01

    A study on brain CT was made in 120 patients of human cysticercosis, which is a rare disease in Japan and clinical symptoms and laboratory data for the diagnosis were also discussed. From the point of therapeutic view, we proposed a new differentiation on brain CT of human cysticercosis, which is divided into two groups according to the alve or dead parasite. Furthermore, we proposed a new type named multiple large and small cysts type on brain CT. The idea of diagnostic standard was made integrating brain CT image, clinical symptoms and labolatory data. (author).

  17. Comparison of iterative model, hybrid iterative, and filtered back projection reconstruction techniques in low-dose brain CT: impact of thin-slice imaging

    Energy Technology Data Exchange (ETDEWEB)

    Nakaura, Takeshi; Iyama, Yuji; Kidoh, Masafumi; Yokoyama, Koichi [Amakusa Medical Center, Diagnostic Radiology, Amakusa, Kumamoto (Japan); Kumamoto University, Department of Diagnostic Radiology, Graduate School of Medical Sciences, Kumamoto (Japan); Oda, Seitaro; Yamashita, Yasuyuki [Kumamoto University, Department of Diagnostic Radiology, Graduate School of Medical Sciences, Kumamoto (Japan); Tokuyasu, Shinichi [Philips Electronics, Kumamoto (Japan); Harada, Kazunori [Amakusa Medical Center, Department of Surgery, Kumamoto (Japan)

    2016-03-15

    The purpose of this study was to evaluate the utility of iterative model reconstruction (IMR) in brain CT especially with thin-slice images. This prospective study received institutional review board approval, and prior informed consent to participate was obtained from all patients. We enrolled 34 patients who underwent brain CT and reconstructed axial images with filtered back projection (FBP), hybrid iterative reconstruction (HIR) and IMR with 1 and 5 mm slice thicknesses. The CT number, image noise, contrast, and contrast noise ratio (CNR) between the thalamus and internal capsule, and the rate of increase of image noise in 1 and 5 mm thickness images between the reconstruction methods, were assessed. Two independent radiologists assessed image contrast, image noise, image sharpness, and overall image quality on a 4-point scale. The CNRs in 1 and 5 mm slice thickness were significantly higher with IMR (1.2 ± 0.6 and 2.2 ± 0.8, respectively) than with FBP (0.4 ± 0.3 and 1.0 ± 0.4, respectively) and HIR (0.5 ± 0.3 and 1.2 ± 0.4, respectively) (p < 0.01). The mean rate of increasing noise from 5 to 1 mm thickness images was significantly lower with IMR (1.7 ± 0.3) than with FBP (2.3 ± 0.3) and HIR (2.3 ± 0.4) (p < 0.01). There were no significant differences in qualitative analysis of unfamiliar image texture between the reconstruction techniques. IMR offers significant noise reduction and higher contrast and CNR in brain CT, especially for thin-slice images, when compared to FBP and HIR. (orig.)

  18. Comparison of iterative model, hybrid iterative, and filtered back projection reconstruction techniques in low-dose brain CT: impact of thin-slice imaging

    International Nuclear Information System (INIS)

    The purpose of this study was to evaluate the utility of iterative model reconstruction (IMR) in brain CT especially with thin-slice images. This prospective study received institutional review board approval, and prior informed consent to participate was obtained from all patients. We enrolled 34 patients who underwent brain CT and reconstructed axial images with filtered back projection (FBP), hybrid iterative reconstruction (HIR) and IMR with 1 and 5 mm slice thicknesses. The CT number, image noise, contrast, and contrast noise ratio (CNR) between the thalamus and internal capsule, and the rate of increase of image noise in 1 and 5 mm thickness images between the reconstruction methods, were assessed. Two independent radiologists assessed image contrast, image noise, image sharpness, and overall image quality on a 4-point scale. The CNRs in 1 and 5 mm slice thickness were significantly higher with IMR (1.2 ± 0.6 and 2.2 ± 0.8, respectively) than with FBP (0.4 ± 0.3 and 1.0 ± 0.4, respectively) and HIR (0.5 ± 0.3 and 1.2 ± 0.4, respectively) (p < 0.01). The mean rate of increasing noise from 5 to 1 mm thickness images was significantly lower with IMR (1.7 ± 0.3) than with FBP (2.3 ± 0.3) and HIR (2.3 ± 0.4) (p < 0.01). There were no significant differences in qualitative analysis of unfamiliar image texture between the reconstruction techniques. IMR offers significant noise reduction and higher contrast and CNR in brain CT, especially for thin-slice images, when compared to FBP and HIR. (orig.)

  19. A CT-ultrasound-coregistered augmented reality enhanced image-guided surgery system and its preliminary study on brain-shift estimation

    International Nuclear Information System (INIS)

    With the combined view on the physical space and the medical imaging data, augmented reality (AR) visualization can provide perceptive advantages during image-guided surgery (IGS). However, the imaging data are usually captured before surgery and might be different from the up-to-date one due to natural shift of soft tissues. This study presents an AR-enhanced IGS system which is capable to correct the movement of soft tissues from the pre-operative CT images by using intra-operative ultrasound images. First, with reconstructing 2-D free-hand ultrasound images to 3-D volume data, the system applies a Mutual-Information based registration algorithm to estimate the deformation between pre-operative and intra-operative ultrasound images. The estimated deformation transform describes the movement of soft tissues and is then applied to the pre-operative CT images which provide high-resolution anatomical information. As a result, the system thus displays the fusion of the corrected CT images or the real-time 2-D ultrasound images with the patient in the physical space through a head mounted display device, providing an immersive augmented-reality environment. For the performance validation of the proposed system, a brain phantom was utilized to simulate brain-shift scenario. Experimental results reveal that when the shift of an artificial tumor is from 5mm ∼ 12mm, the correction rates can be improved from 32% ∼ 45% to 87% ∼ 95% by using the proposed system.

  20. A CT-ultrasound-coregistered augmented reality enhanced image-guided surgery system and its preliminary study on brain-shift estimation

    Science.gov (United States)

    Huang, C. H.; Hsieh, C. H.; Lee, J. D.; Huang, W. C.; Lee, S. T.; Wu, C. T.; Sun, Y. N.; Wu, Y. T.

    2012-08-01

    With the combined view on the physical space and the medical imaging data, augmented reality (AR) visualization can provide perceptive advantages during image-guided surgery (IGS). However, the imaging data are usually captured before surgery and might be different from the up-to-date one due to natural shift of soft tissues. This study presents an AR-enhanced IGS system which is capable to correct the movement of soft tissues from the pre-operative CT images by using intra-operative ultrasound images. First, with reconstructing 2-D free-hand ultrasound images to 3-D volume data, the system applies a Mutual-Information based registration algorithm to estimate the deformation between pre-operative and intra-operative ultrasound images. The estimated deformation transform describes the movement of soft tissues and is then applied to the pre-operative CT images which provide high-resolution anatomical information. As a result, the system thus displays the fusion of the corrected CT images or the real-time 2-D ultrasound images with the patient in the physical space through a head mounted display device, providing an immersive augmented-reality environment. For the performance validation of the proposed system, a brain phantom was utilized to simulate brain-shift scenario. Experimental results reveal that when the shift of an artificial tumor is from 5mm ~ 12mm, the correction rates can be improved from 32% ~ 45% to 87% ~ 95% by using the proposed system.

  1. TH-A-18C-09: Ultra-Fast Monte Carlo Simulation for Cone Beam CT Imaging of Brain Trauma

    International Nuclear Information System (INIS)

    Purpose: Application of cone-beam CT (CBCT) to low-contrast soft tissue imaging, such as in detection of traumatic brain injury, is challenged by high levels of scatter. A fast, accurate scatter correction method based on Monte Carlo (MC) estimation is developed for application in high-quality CBCT imaging of acute brain injury. Methods: The correction involves MC scatter estimation executed on an NVIDIA GTX 780 GPU (MC-GPU), with baseline simulation speed of ~1e7 photons/sec. MC-GPU is accelerated by a novel, GPU-optimized implementation of variance reduction (VR) techniques (forced detection and photon splitting). The number of simulated tracks and projections is reduced for additional speed-up. Residual noise is removed and the missing scatter projections are estimated via kernel smoothing (KS) in projection plane and across gantry angles. The method is assessed using CBCT images of a head phantom presenting a realistic simulation of fresh intracranial hemorrhage (100 kVp, 180 mAs, 720 projections, source-detector distance 700 mm, source-axis distance 480 mm). Results: For a fixed run-time of ~1 sec/projection, GPU-optimized VR reduces the noise in MC-GPU scatter estimates by a factor of 4. For scatter correction, MC-GPU with VR is executed with 4-fold angular downsampling and 1e5 photons/projection, yielding 3.5 minute run-time per scan, and de-noised with optimized KS. Corrected CBCT images demonstrate uniformity improvement of 18 HU and contrast improvement of 26 HU compared to no correction, and a 52% increase in contrast-tonoise ratio in simulated hemorrhage compared to “oracle” constant fraction correction. Conclusion: Acceleration of MC-GPU achieved through GPU-optimized variance reduction and kernel smoothing yields an efficient (<5 min/scan) and accurate scatter correction that does not rely on additional hardware or simplifying assumptions about the scatter distribution. The method is undergoing implementation in a novel CBCT dedicated to brain

  2. TH-A-18C-09: Ultra-Fast Monte Carlo Simulation for Cone Beam CT Imaging of Brain Trauma

    Energy Technology Data Exchange (ETDEWEB)

    Sisniega, A; Zbijewski, W; Stayman, J [Department of Biomedical Engineering, Johns Hopkins University (United States); Yorkston, J [Carestream Health (United States); Aygun, N [Department of Radiology, Johns Hopkins University (United States); Koliatsos, V [Department of Neurology, Johns Hopkins University (United States); Siewerdsen, J [Department of Biomedical Engineering, Johns Hopkins University (United States); Department of Radiology, Johns Hopkins University (United States)

    2014-06-15

    Purpose: Application of cone-beam CT (CBCT) to low-contrast soft tissue imaging, such as in detection of traumatic brain injury, is challenged by high levels of scatter. A fast, accurate scatter correction method based on Monte Carlo (MC) estimation is developed for application in high-quality CBCT imaging of acute brain injury. Methods: The correction involves MC scatter estimation executed on an NVIDIA GTX 780 GPU (MC-GPU), with baseline simulation speed of ~1e7 photons/sec. MC-GPU is accelerated by a novel, GPU-optimized implementation of variance reduction (VR) techniques (forced detection and photon splitting). The number of simulated tracks and projections is reduced for additional speed-up. Residual noise is removed and the missing scatter projections are estimated via kernel smoothing (KS) in projection plane and across gantry angles. The method is assessed using CBCT images of a head phantom presenting a realistic simulation of fresh intracranial hemorrhage (100 kVp, 180 mAs, 720 projections, source-detector distance 700 mm, source-axis distance 480 mm). Results: For a fixed run-time of ~1 sec/projection, GPU-optimized VR reduces the noise in MC-GPU scatter estimates by a factor of 4. For scatter correction, MC-GPU with VR is executed with 4-fold angular downsampling and 1e5 photons/projection, yielding 3.5 minute run-time per scan, and de-noised with optimized KS. Corrected CBCT images demonstrate uniformity improvement of 18 HU and contrast improvement of 26 HU compared to no correction, and a 52% increase in contrast-tonoise ratio in simulated hemorrhage compared to “oracle” constant fraction correction. Conclusion: Acceleration of MC-GPU achieved through GPU-optimized variance reduction and kernel smoothing yields an efficient (<5 min/scan) and accurate scatter correction that does not rely on additional hardware or simplifying assumptions about the scatter distribution. The method is undergoing implementation in a novel CBCT dedicated to brain

  3. Net-based data transfer and automatic image fusion of metabolic (PET) and morphologic (CT/MRI) images for radiosurgical planning of brain tumors

    International Nuclear Information System (INIS)

    Aim: The main purpose of radiosurgery in comparison to conventional radiotherapy of brain tumors is to reach a higher radiation dose in the tumor and sparing normal brain tissue as much as possible. To reach this aim it is crucial to define the target volume extremely accurately. For this purpose, MRI and CT examinations are used for radiotherapy planning. In certain cases, however, metabolic information obtained by positron emission tomography (PET) may be useful to achieve a higher therapeutic accuracy by sparing important brain structures. This can be the case, i.e. in low grade astrocytomas for exact delineation of vital tumor as well as in differentiating scaring tissue from tumor recurrence and edema after operation. For this purpose, radiolabeled aminoacid analogues (e.g. C-11 methionine) and recently O-2-[18F] Fluorethyl-L-Tyrosin (F-18 FET) have been introduced as PET tracers to detect the area of highest tumor metabolism which allows to obtain additional information as compared to FDG-PET that reflects the local glucose metabolism. In these cases, anatomical and metabolic data have to be combined with the technique of digital image fusion to exactly determine the target volume, the isodoses and the area where the highest dose has to be applied. Materials: We have set up a data transfer from the PET Center of the Zentralklinik Bad Berka with the Department of Stereotactic Radiation at the Helios Klinik Erfurt (distance approx. 25 km) to enable this kind of image fusion. PET data (ECAT EXACT 47, Siemens/CTI) are transferred to a workstation (NOVALIS) in the Dept. of Stereotactic Radiation to be co-registered with the CT or MRI data of the patient. All PET images are in DICOM format (obtained by using a HERMES computer, Nuclear Diagnostics, Sweden) and can easily be introduced into the NOVALIS workstation. The software uses the optimation of mutual information to achieve a good fusion quality. Sometimes manual corrections have to be performed to get an

  4. Classification of CT-brain slices based on local histograms

    Science.gov (United States)

    Avrunin, Oleg G.; Tymkovych, Maksym Y.; Pavlov, Sergii V.; Timchik, Sergii V.; Kisała, Piotr; Orakbaev, Yerbol

    2015-12-01

    Neurosurgical intervention is a very complicated process. Modern operating procedures based on data such as CT, MRI, etc. Automated analysis of these data is an important task for researchers. Some modern methods of brain-slice segmentation use additional data to process these images. Classification can be used to obtain this information. To classify the CT images of the brain, we suggest using local histogram and features extracted from them. The paper shows the process of feature extraction and classification CT-slices of the brain. The process of feature extraction is specialized for axial cross-section of the brain. The work can be applied to medical neurosurgical systems.

  5. SU-C-18A-05: Registration Accuracy of MR-Based Images to On-Board Megavoltage Cone-Beam CT for Brain Patient Setup

    International Nuclear Information System (INIS)

    Purpose: To quantify the difference in isocenter shifts when co-registering MR and MR-based pseudo CTs (pCT) with on-board megavoltage conebeam CT (CBCT) images. Methods: Fast Spoiled Gradient Echo MRs were used to generate pCTs (research version of Advantage Sim MD™, GE Healthcare) for ten patients who had prior brain radiotherapy. The planning CT (rCT) for each was co-registered with the MR, and the plan isocenter and two other reference points were transferred to the MR and pCT. CBCT images (with the machine isocenter) from a single treatment day were coregistered with the 3 test images (MR, pCT and rCT), by two observers and by an automated registration algorithm. The reference points were used to calculate patient shifts and rotations from the registrations. The shifts calculated from the test image registrations were compared to each other and to the shifts performed by the therapists who treated the patients on that day. Results: The average difference in absolute value between the isocenter shifts from the MR-, pCT- and rCT-CBCT registrations, and the therapist shifts, were 2.02, 3.01 and 0.89 mm (craniocaudal), 1.14, 1.34 and 0.46 mm (lateral), and 1.37, 3.43 and 1.43 mm (vertical), respectively. The MR- and pCT-CBCT registrations differed by 1.99, and 2.53 mm (craniocaudal), 1.36, and 1.37 mm (lateral), and 0.74 and 2.34 mm (vertical), respectively, from the average rCT-CBCT shifts. On average, differences of 2.39 (craniocaudal), 1.28 (lateral) and 2.84 mm (vertical) were seen between the MR and pCT shifts. Rotations relative to the CBCT coordinate system were on average <2° for the MR and rCT, and <6° for the pCT. Conclusion: In this study, FSPGR MR-CBCT registrations were more precise compared to the pCT-CBCT registrations. For improved accuracy, MR sequences that are optimal for bony anatomy visualization are necessary. GE healthcare has provided a research version of Advantage Sim MD to UCSF. No financial support was provided

  6. Brain lesions in eclampsia: value of CT and MR imaging. Report of one case

    International Nuclear Information System (INIS)

    Eclampsia is defined as the development of convulsion and/or coma during pregnancy. Physiopathology remains unclear. We report a case of eclampsia and review the literature. CT, MR and angiographic findings are described. Value of various techniques is discussed. (authors). 11 refs., 3 figs

  7. CT image of thymoma

    Energy Technology Data Exchange (ETDEWEB)

    Morioka, Nobuo; Shudo, Yuji; Jahana, Masanobu; Matsuki, Tsutomu; Kotani, Kazuhiko (Tottori Univ., Yonago (Japan). School of Medicine)

    1983-10-01

    Computor tomographic images of 11 patients who had had thymectomy for myasthenia gravis or thymoma were studied retrospectively. Of those 11 patients, malignant thymoma and benign condition including normal thymus were 6 and 5 respectively. On CT, calcification and lobulation with irregular margin seem to be reliable findings of malignancy. Defect or abscence of fatty plane and non-homogenous density are ancillary.

  8. Pulmonary hypertension CT imaging

    International Nuclear Information System (INIS)

    Full text: The right heart catheterization is the gold standard in the diagnosis and determines the severity of pulmonary hypertension. The significant technical progress of noninvasive diagnostic imaging methods significantly improves the pixel density and spatial resolution in the study of cardiovascular structures, thus changes their role and place in the overall diagnostic plan. Learning points: What is the etiology, clinical manifestation and general pathophysiological disorders in pulmonary hypertension. What are the established diagnostic methods in the diagnosis and follow-up of patients with pulmonary hypertension. What is the recommended protocol for CT scanning for patients with clinically suspected or documented pulmonary hypertension. What are the important diagnostic findings in CT scan of a patient with pulmonary hypertension. Discussion: The prospect of instantaneous complex - anatomical and functional cardiopulmonary and vascular diagnostics seems extremely attractive. The contrast enhanced multislice computed (CT ) and magnetic resonance imaging are very suitable methods for imaging the structures of the right heart, with the possibility of obtaining multiple projections and three-dimensional imaging reconstructions . There are specific morphological features that, if carefully analyzed, provide diagnostic information. Thus, it is possible to avoid or at least reduce the frequency of use of invasive diagnostic cardiac catheterization in patients with pulmonary hypertension. Conclusion: This review focuses on the use of contrast-enhanced CT for comprehensive evaluation of patients with pulmonary hypertension and presents the observed characteristic changes in the chest, lung parenchyma , the structures of the right half of the heart and pulmonary vessels

  9. Experience of Dual Time Point Brain F-18 FDG PET/CT Imaging in Patients with Infections Disease

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Dae Weung; Kim, Chang Guhn; Park, Soon Ah; Jung, Sang Ah [Wonkwang University School of Medicine, Iksan (Korea, Republic of)

    2010-06-15

    Dual time point FDG PET imaging (DTPI) has been considered helpful for discrimination of benign and malignant disease, and staging lymph node status in patients with pulmonary malignancy. However, DTPI for benign disease has been rarely reported, and it may show a better description of metabolic status and extent of benign infection disease than early imaging only. The authors report on the use F-18 fluorodeoxyglucose (FDG) positron emission tomography (PET)/computed tomography (CT) imaging with additional delayed imaging on a 52-year-old man with sparganosis and a 70-year-old man with tuberculous meningitis. To the best of our knowledge, this is the first report on dual time point PET/CT imaging in patients with cerebral sparganosis and tuberculous meningitis.

  10. Qualitative investigation of structural changes of the brain with CT and MR imaging in normal aging and dementia

    International Nuclear Information System (INIS)

    The authors studied 29 demented patients and 10 controls with MR imaging, CR, and F-18 deoxyglucose positron emission tomography scans. The authors compared the sensitivity of MR imaging and CT in the detection and grading of cortical atrophy, ventricular dilatation (VD), white matter disease (WMD), and periventribular hyperintensity (PVH). Identical incidences of VD and WMD were noted in both groups: PVH and gray matter disease (GMD) were seen more often in patients. The average cerebral metabolic rate (CMRglu) was significantly lower in patients and declined with the severity of GMD, WMD, and VD. Regional WMD did not affect the regional-global CMRglu ratio. CT and MR imaging were found to have equal sensitivity in the detection and grading of atrophy and VD; MR imaging was more sensitive in detecting WMD, PVH, and cortical GMD

  11. Evaluation of Clinical Contributions Provided by Addition of the Brain, Calvarium, and Scalp to the Limited Whole Body Imaging Area in FDG-PET/CT Tumor Imaging

    Directory of Open Access Journals (Sweden)

    Bekir Tasdemir

    2014-01-01

    Full Text Available Purpose. The aim of this study was to detect additional findings in whole body FDG-PET/CT scan including the brain, calvarium, and scalp (compared to starting from the base of the skull in cancer patients and to determine contributions of these results to tumor staging and treatment protocols. Materials and Methods. We noted whether the findings related to the brain, calvarium, and scalp in 1359 patients had a potential to modify staging of the disease, chemotherapy protocol, radiotherapy protocol, and surgical management. We identified rates of metastatic findings on the brain, calvarium, and scalp according to the tumor types on FDG-PET/CT scanning. Results. We found FDG-PET/CT findings for malignancy above the base of the skull in 42 patients (3.1%, one of whom was a patient with an unknown primary tumor. Twenty-two of the metastatic findings were in the brain, 16 were in the calvarium, and two were in the scalp. Conclusion. This study has demonstrated that addition of the brain to the limited whole body FDG-PET/CT scanning may provide important contributions to the patient’s clinical management especially in patients with lung cancer, bladder cancer, malignant melanoma, breast cancer, stomach cancer, and unknown primary tumor.

  12. Radiation (XRT)-induced disease of the primate brain: Anatomic-pathologic correlation with CT and MR imaging

    International Nuclear Information System (INIS)

    Nine healthy primates were used in two toxicity studies. In the first study, BUdR radiosensitization was performed with external beam x-irradiation of 6,000 cGy in five rhesus monkeys (three controls, two with pumps implanted in the common carotid artery for delivery of BUdR). MR imaging was performed 3 and 9 months after treatment. Bihemispheric lesions with long T1 and T2 values were seen in three animals. Lesion topography on MR imaging exactly matched histologic zones of microinfarcts and endothelial proliferation with surrounding parenchymal edema. MR imaging and pathologic findings in two animals were normal. In the second study, interstitial radiation therapy was delivered by stereotaxic implantation of a single I-125 seed of 3,000 cGy in two pigtail monkeys and of 6,000 cGy in another two monkeys. CT and MR imaging were performed 0, 4, 7, and 10 weeks after seed placement. MR imaging revealed progressive development of lesions with long T1 values and intermediate T2 values at the center, intermediate T1 and T2 values at the rim, and long T1, long T2 values at the periphery. These lesions were exactly centered on seed placement. The rim of intermediate values exactly matched pathologic zones of contrast enhancement on CT. The three zones seen on MR imaging corresponded to similar histologic zones of central coagulation necrosis, microinfarctions and endothelial proliferation at the rim, and peripheral edema. Lesion calcification was seen diffusely on pathologic study, poorly on MR imaging, and fairly on CT

  13. A comparative study of surface- and volume-based techniques for the automatic registration between CT and SPECT brain images

    International Nuclear Information System (INIS)

    Image registration of multimodality images is an essential task in numerous applications in three-dimensional medical image processing. Medical diagnosis can benefit from the complementary information in different modality images. Surface-based registration techniques, while still widely used, were succeeded by volume-based registration algorithms that appear to be theoretically advantageous in terms of reliability and accuracy. Several applications of such algorithms for the registration of CT-MRI, CT-PET, MRI-PET, and SPECT-MRI images have emerged in the literature, using local optimization techniques for the matching of images. Our purpose in this work is the development of automatic techniques for the registration of real CT and SPECT images, based on either surface- or volume-based algorithms. Optimization is achieved using genetic algorithms that are known for their robustness. The two techniques are compared against a well-established method, the Iterative Closest Point--ICP. The correlation coefficient was employed as an independent measure of spatial match, to produce unbiased results. The repeated measures ANOVA indicates the significant impact of the choice of registration method on the magnitude of the correlation (F=4.968, p=0.0396). The volume-based method achieves an average correlation coefficient value of 0.454 with a standard deviation of 0.0395, as opposed to an average of 0.380 with a standard deviation of 0.0603 achieved by the surface-based method and an average of 0.396 with a standard deviation equal to 0.0353 achieved by ICP. The volume-based technique performs significantly better compared to both ICP (p<0.05, Neuman Keuls test) and the surface-based technique (p<0.05, Neuman-Keuls test). Surface-based registration and ICP do not differ significantly in performance

  14. Brain imaging and brain function

    International Nuclear Information System (INIS)

    This book is a survey of the applications of imaging studies of regional cerebral blood flow and metabolism to the investigation of neurological and psychiatric disorders. Contributors review imaging techniques and strategies for measuring regional cerebral blood flow and metabolism, for mapping functional neural systems, and for imaging normal brain functions. They then examine the applications of brain imaging techniques to the study of such neurological and psychiatric disorders as: cerebral ischemia; convulsive disorders; cerebral tumors; Huntington's disease; Alzheimer's disease; depression and other mood disorders. A state-of-the-art report on magnetic resonance imaging of the brain and central nervous system rounds out the book's coverage

  15. Problems in CT diagnosis of the aging brain

    International Nuclear Information System (INIS)

    The different methods of measuring the intracranial CSF spaces on CT images are described. The values obtained are demonstrated to separate the normal aging brain from the brain in senile dementia of Alzheimer's type. The CT criteria for the diagnosis of multiinfarctdementia are shown. The significance of CT studies in senile depression is discussed. The problem of vascular encephalopathy (leukoaraiosis) in normal aging of the brain and in dementia is considered in particular, and even the occurrence of intracranial space-occupying lesions and normal pressure hydrocephalus, as treatable causes of dementia and depression, are mentioned. The data and results of my own CT research on normal brain aging, dementia and depression are presented with reference to the literature. (orig.)

  16. A STUDY ON YIELD AND USEFULNESS OF NON-CONTRAST CT BRAIN IMAGING IN ACUTE STROKE AT A TERTIARY CARE INSTITUTE IN SOUTH INDIA

    Directory of Open Access Journals (Sweden)

    Jayanthi

    2016-05-01

    Full Text Available BACKGROUND Non-enhanced CT scanning of the head remains the first-line diagnostic test for the emergency evaluation of acute stroke because of its speed, its convenient availability at most hospitals and its ability to sensitively depict intracranial haemorrhage. [1] This is an observational study done to ascertain the yield and usefulness of non-contrast CT brain imaging in acute stroke in a tertiary care centre. METHODS This was a prospective observational study done from June 2015 - November 2015 in a tertiary care centre. The study included 75 patients above 18 years of age who presented with any new-onset neurological deficit to our hospital. CT imaging was done for all those patients. Pregnant patients and those with previous neurological deficits were excluded from this study. A detailed study on the sex, age of the patient, time of presentation to our hospital, types of stroke along with site of involvement were studied. Data was recorded and analysed. RESULTS Amongst the 75 patients we studied 56 were females, 44 were males, 64% of our patients had infarct, 21% had haemorrhage, 19% of our patients had normal study at the time of presentation. Amongst those who had evidence of CT proven infarct, 3 patients presented to us within 6 hours, 6 patients between 6-12 hours, 26 patients between 12-24 hours, 10 patients after 24 hours. Amongst the 19% who had no evidence of stroke in imaging studies, 85% presented within 6 hours to our hospital. CONCLUSIONS Our study concluded that females are predominant in patients presenting with stroke, most common cause of stroke was infarct with capsuloganglionic region being the most common site of involvement and radiological yield of evidence of plain CT had positive correlation with advancing age of infarct.

  17. Color-coded perfused blood volume imaging using multidetector CT: initial results of whole-brain perfusion analysis in acute cerebral ischemia

    International Nuclear Information System (INIS)

    Computed tomography (CT) is still the primary imaging modality following acute stroke. To evaluate a prototype of software for the calculation of color-coded whole-brain perfused blood volume (PBV) images from CT angiography (CTA) and nonenhanced CT (NECT) scans, we studied 14 patients with suspected acute ischemia of the anterior cerebral circulation. PBV calculations were performed retrospectively. The detection rate of ischemic changes in the PBV images was compared with NECT. The volume of ischemic changes in PBV was correlated with the infarct volume on follow-up examination taking potential vessel recanalization into account. PBV demonstrated ischemic changes in 12/12 patients with proven infarction and was superior to NECT (8/12) in the detection of early ischemia. Moreover, PBV demonstrated the best correlation coefficient with the follow-up infarct volume (Pearson's R = 0.957; P = 0.003) for patients with proven recanalization of initially occluded cerebral arteries. In summary, PBV appears to be more accurate in the detection of early infarction compared to NECT and mainly visualizes the irreversibly damaged ischemic tissue. (orig.)

  18. SU-E-J-47: Comparison of Online Image Registrations of Varian TrueBeam Cone-Beam CT and BrainLab ExacTrac Imaging Systems

    International Nuclear Information System (INIS)

    Purpose To compare online image registrations of TrueBeam cone-beam CT (CBCT) and BrainLab ExacTrac imaging systems. Methods Tests were performed on a Varian TrueBeam STx linear accelerator (Version 2.0), which is integrated with a BrainLab ExacTrac imaging system (Version 6.0.5). The study was focused on comparing the online image registrations for translational shifts. A Rando head phantom was placed on treatment couch and immobilized with a BrainLab mask. The phantom was shifted by moving the couch translationally for 8 mm with a step size of 1 mm, in vertical, longitudinal, and lateral directions, respectively. At each location, the phantom was imaged with CBCT and ExacTrac x-ray. CBCT images were registered with TrueBeam and ExacTrac online registration algorithms, respectively. And ExacTrac x-ray image registrations were performed. Shifts calculated from different registrations were compared with nominal couch shifts. Results The averages and ranges of absolute differences between couch shifts and calculated phantom shifts obtained from ExacTrac x-ray registration, ExacTrac CBCT registration with default window, ExaxTrac CBCT registration with adjusted window (bone), Truebeam CBCT registration with bone window, and Truebeam CBCT registration with soft tissue window, were: 0.07 (0.02–0.14), 0.14 (0.01–0.35), 0.12 (0.02–0.28), 0.09 (0–0.20), and 0.06 (0–0.10) mm, in vertical direction; 0.06 (0.01–0.12), 0.27 (0.07–0.57), 0.23 (0.02–0.48), 0.04 (0–0.10), and 0.08 (0– 0.20) mm, in longitudinal direction; 0.05 (0.01–0.21), 0.35 (0.14–0.80), 0.25 (0.01–0.56), 0.19 (0–0.40), and 0.20 (0–0.40) mm, in lateral direction. Conclusion The shifts calculated from ExacTrac x-ray and TrueBeam CBCT registrations were close to each other (the differences between were less than 0.40 mm in any direction), and had better agreements with couch shifts than those from ExacTrac CBCT registrations. There were no significant differences between True

  19. SU-E-J-47: Comparison of Online Image Registrations of Varian TrueBeam Cone-Beam CT and BrainLab ExacTrac Imaging Systems

    Energy Technology Data Exchange (ETDEWEB)

    Li, J; Shi, W; Andrews, D; Werner-Wasik, M; Yu, Y; Liu, H [Thomas Jefferson University, Philadelphia, PA (United States)

    2015-06-15

    Purpose To compare online image registrations of TrueBeam cone-beam CT (CBCT) and BrainLab ExacTrac imaging systems. Methods Tests were performed on a Varian TrueBeam STx linear accelerator (Version 2.0), which is integrated with a BrainLab ExacTrac imaging system (Version 6.0.5). The study was focused on comparing the online image registrations for translational shifts. A Rando head phantom was placed on treatment couch and immobilized with a BrainLab mask. The phantom was shifted by moving the couch translationally for 8 mm with a step size of 1 mm, in vertical, longitudinal, and lateral directions, respectively. At each location, the phantom was imaged with CBCT and ExacTrac x-ray. CBCT images were registered with TrueBeam and ExacTrac online registration algorithms, respectively. And ExacTrac x-ray image registrations were performed. Shifts calculated from different registrations were compared with nominal couch shifts. Results The averages and ranges of absolute differences between couch shifts and calculated phantom shifts obtained from ExacTrac x-ray registration, ExacTrac CBCT registration with default window, ExaxTrac CBCT registration with adjusted window (bone), Truebeam CBCT registration with bone window, and Truebeam CBCT registration with soft tissue window, were: 0.07 (0.02–0.14), 0.14 (0.01–0.35), 0.12 (0.02–0.28), 0.09 (0–0.20), and 0.06 (0–0.10) mm, in vertical direction; 0.06 (0.01–0.12), 0.27 (0.07–0.57), 0.23 (0.02–0.48), 0.04 (0–0.10), and 0.08 (0– 0.20) mm, in longitudinal direction; 0.05 (0.01–0.21), 0.35 (0.14–0.80), 0.25 (0.01–0.56), 0.19 (0–0.40), and 0.20 (0–0.40) mm, in lateral direction. Conclusion The shifts calculated from ExacTrac x-ray and TrueBeam CBCT registrations were close to each other (the differences between were less than 0.40 mm in any direction), and had better agreements with couch shifts than those from ExacTrac CBCT registrations. There were no significant differences between True

  20. Quantitative evaluation of benign meningioma and hemangiopericytoma with peritumoral brain edema by 64-slice CT perfusion imaging

    Institute of Scientific and Technical Information of China (English)

    REN Guang; CHEN Shuang; WANG Yin; ZHU Rui-jiang; GENG Dao-ying; FENG Xiao-yuan

    2010-01-01

    Background Hemangiopericytomas (HPCs) have a relentless tendency for local recurrence and metastases,differentiating between benign meningiomas and HPCs before surgery is important for both treatment planning and the prognosis appraisal.The purpose of this study was to evaluate the correlations between CT perfusion parameters and microvessel density (MVD) in extra-axial tumors and the possible role of CT perfusion imaging in preoperatively differentiating benign meningiomas and HPCs.Methods Seventeen patients with benign meningiomas and peritumoral edema, 12 patients with HPCs and peritumoral edema underwent 64-slice CT perfusion imaging pre-operation.Perfusion was calculated using the Patlak method.The quantitative parameters, include cerebral blood volume (CBV), permeability surface (PS) of parenchyma, peritumoral edema among benign meningiomas and HPCs were compared respectively.CBV and PS in parenchyma, peritumoral edema of benign meningiomas and HPCs were also compared to that of the contrallateral normal white matter respectively.The correlations between CBV, PS of tumoral parenchyma and MVD were examined.Results The value of CBV and PS in parenchyma of HPCs were significantly higher than that of benign meningiomas (P<0.05), while the values of CBV and PS in peritumoral edema of benign meningiomas and HPCs were not significantly different (P >0.05).MVD in parenchyma of HPCs were significantly higher than that of benign meningiomas (P<0.05).There were positive correlations between CBV and MVD (r=0.648, P<0.05), PS and MVD (r=0.541, P<0.05) respectively.Furthermore, the value of CBV and PS in parenchyma of benign meningiomas and HPCs were significantly higher than that of contrallateral normal white matter (P<0.05), the value of CBV in peritumoral edema of benign meningiomas and HPCs were significantly lower than that of contrallateral normal white matter (P<0.05), while the value of PS in peritumoral edema of benign meningiomas and HPCs were not

  1. Brain MR imaging in child abuse

    International Nuclear Information System (INIS)

    Intracranial injuries represent the most severe manifestation of child abuse. CT of the brain is the current standard for evaluation of these infants; however, MR imaging offers several potential advantages. MR imaging and CT were performed in ten infants who suffered intracranial trauma owing to child abuse. CT was slightly better at demonstrating subarachnoid hemorrhage and had definite advantages for defining fractures. MR imaging was superior in the demonstration of subacute extraaxial hemorrhage, deep brain injuries owing to shearing effects from shaking, and anoxic injuries. MR imaging has a definite complementary role in the evaluation of acute intracranial trauma in child abuse victims

  2. Suitability of helical multislice acquisition technique for routine unenhanced brain CT: an image quality study using a 16-row detector configuration

    International Nuclear Information System (INIS)

    Subjective and objective image quality (IQ) criteria, radiation doses, and acquisition times were compared using incremental monoslice, incremental multislice, and helical multislice acquisition techniques for routine unenhanced brain computed tomography (CT). Twenty-four patients were examined by two techniques in the same imaging session using a 16-row CT system equipped with 0.75-width detectors. Contiguous ''native'' 3-mm-thick slices were reconstructed for all acquisitions from four detectors for each slice (4 x 0.75 mm), with one channel available per detector. Two protocols were tailored to compare: (1) one-slice vs four-slice incremental images; (2) incremental vs helical four-slice images. Two trained observers independently scored 12 subjective items of IQ. Preference for the technique was assessed by one-tailed t test and the interobserver variation by two-tailed t test. The two observers gave very close IQ scores for the three techniques without significant interobserver variations. Measured IQ parameters failed to reveal any difference between techniques, and an approximate half radiation dose reduction was obtained by using the full 16-row configuration. Acquisition times were cumulatively shortened by using the multislice and the helical modality. (orig.)

  3. Classification of Medical Brain Images

    Institute of Scientific and Technical Information of China (English)

    Pan Haiwei(潘海为); Li Jianzhong; Zhang Wei

    2003-01-01

    Since brain tumors endanger people's living quality and even their lives, the accuracy of classification becomes more important. Conventional classifying techniques are used to deal with those datasets with characters and numbers. It is difficult, however, to apply them to datasets that include brain images and medical history (alphanumeric data), especially to guarantee the accuracy. For these datasets, this paper combines the knowledge of medical field and improves the traditional decision tree. The new classification algorithm with the direction of the medical knowledge not only adds the interaction with the doctors, but also enhances the quality of classification. The algorithm has been used on real brain CT images and a precious rule has been gained from the experiments. This paper shows that the algorithm works well for real CT data.

  4. Developmental venous anomalies: appearance on whole-brain CT digital subtraction angiography and CT perfusion

    Energy Technology Data Exchange (ETDEWEB)

    Hanson, Eric H. [Advanced Medical Imaging and Genetics (Amigenics), Las Vegas, NV (United States); Touro University Nevada College of Osteopathic Medicine, Henderson, NV (United States); University of Nevada Las Vegas, Department of Health Physics and Diagnostic Sciences, 4505 Maryland Parkway, Box 453037, Las Vegas, NV (United States); Amigenics, Inc, Las Vegas, NV (United States); Roach, Cayce J. [Advanced Medical Imaging and Genetics (Amigenics), Las Vegas, NV (United States); University of Nevada Las Vegas, School of Life Sciences, Las Vegas, NV (United States); Ringdahl, Erik N. [University of Nevada Las Vegas, Department of Psychology, Las Vegas, NV (United States); Wynn, Brad L. [Family Medicine Spokane, Spokane, WA (United States); DeChancie, Sean M.; Mann, Nathan D. [Touro University Nevada College of Osteopathic Medicine, Henderson, NV (United States); Diamond, Alan S. [CHW Nevada Imaging Company, Nevada Imaging Centers, Spring Valley, Las Vegas, NV (United States); Orrison, William W. [Touro University Nevada College of Osteopathic Medicine, Henderson, NV (United States); University of Nevada Las Vegas, Department of Health Physics and Diagnostic Sciences, 4505 Maryland Parkway, Box 453037, Las Vegas, NV (United States); CHW Nevada Imaging Company, Nevada Imaging Centers, Spring Valley, Las Vegas, NV (United States); University of Nevada School of Medicine, Department of Medical Education, Reno, NV (United States)

    2011-05-15

    Developmental venous anomalies (DVA) consist of dilated intramedullary veins that converge into a large collecting vein. The appearance of these anomalies was evaluated on whole-brain computed tomography (CT) digital subtraction angiography (DSA) and CT perfusion (CTP) studies. CT data sets of ten anonymized patients were retrospectively analyzed. Five patients had evidence of DVA and five age- and sex-matched controls were without known neurovascular abnormalities. CT angiograms, CT arterial-venous views, 4-D CT DSA and CTP maps were acquired on a dynamic volume imaging protocol on a 320-detector row CT scanner. Whole-brain CTP parameters were evaluated for cerebral blood flow (CBF), cerebral blood volume (CBV), time to peak (TTP), mean transit time (MTT), and delay. DSA was utilized to visualize DVA anatomy. Radiation dose was recorded from the scanner console. Increased CTP values were present in the DVA relative to the unaffected contralateral hemisphere of 48%, 32%, and 26%; and for the control group with matched hemispheric comparisons of 2%, -10%, and 9% for CBF, CBV, and MTT, respectively. Average effective radiation dose was 4.4 mSv. Whole-brain DSA and CTP imaging can demonstrate a characteristic appearance of altered DVA hemodynamic parameters and capture the anomalies in superior cortices of the cerebrum and the cerebellum. Future research may identify the rare subsets of patients at increased risk of adverse outcomes secondary to the altered hemodynamics to facilitate tailored imaging surveillance and application of appropriate preventive therapeutic measures. (orig.)

  5. Developmental venous anomalies: appearance on whole-brain CT digital subtraction angiography and CT perfusion

    International Nuclear Information System (INIS)

    Developmental venous anomalies (DVA) consist of dilated intramedullary veins that converge into a large collecting vein. The appearance of these anomalies was evaluated on whole-brain computed tomography (CT) digital subtraction angiography (DSA) and CT perfusion (CTP) studies. CT data sets of ten anonymized patients were retrospectively analyzed. Five patients had evidence of DVA and five age- and sex-matched controls were without known neurovascular abnormalities. CT angiograms, CT arterial-venous views, 4-D CT DSA and CTP maps were acquired on a dynamic volume imaging protocol on a 320-detector row CT scanner. Whole-brain CTP parameters were evaluated for cerebral blood flow (CBF), cerebral blood volume (CBV), time to peak (TTP), mean transit time (MTT), and delay. DSA was utilized to visualize DVA anatomy. Radiation dose was recorded from the scanner console. Increased CTP values were present in the DVA relative to the unaffected contralateral hemisphere of 48%, 32%, and 26%; and for the control group with matched hemispheric comparisons of 2%, -10%, and 9% for CBF, CBV, and MTT, respectively. Average effective radiation dose was 4.4 mSv. Whole-brain DSA and CTP imaging can demonstrate a characteristic appearance of altered DVA hemodynamic parameters and capture the anomalies in superior cortices of the cerebrum and the cerebellum. Future research may identify the rare subsets of patients at increased risk of adverse outcomes secondary to the altered hemodynamics to facilitate tailored imaging surveillance and application of appropriate preventive therapeutic measures. (orig.)

  6. CT Angiography in the Diagnosis of Brain Death

    International Nuclear Information System (INIS)

    Summary Brain death is defined as the irreversible cessation of functioning of the entire brain, including the brainstem. Brain death is principally established using clinical criteria including coma, absence of brainstem reflexes and loss of central drive to breathe assessed with apnea test. In situations in which clinical testing cannot be performed or when uncertainty exists about the reliability of its parts due to confounding conditions ancillary tests (i.a. imaging studies) may be useful. The objective of ancillary tests in the diagnosis of brain death is to demonstrate the absence of cerebral electrical activity (EEG and evoked potentials) or cerebral circulatory arrest. In clinical practice catheter cerebral angiography, perfusion scintigraphy, transcranial Doppler sonography, CT angiography and MR angiography are used. Other methods, like perfusion CT, xenon CT, MR spectroscopy, diffusion weighted MRI and functional MRI are being studied as potentially useful in the diagnosis of brain death. CT angiography has recently attracted attention as a promising alternative to catheter angiography – a reference test in the diagnosis of brain death. Since 1998 several major studies were published and national guidelines were introduced in several countries (e.g. in France, Austria, Switzerland, the Netherlands and Canada). This paper reviews technique, characteristic findings and criteria for the diagnosis of cerebral circulatory arrest in CT angiography

  7. Dynamic CT perfusion imaging of intra-axial brain tumours: differentiation of high-grade gliomas from primary CNS lymphomas

    International Nuclear Information System (INIS)

    Perfusion computed tomography (PCT) allows to quantitatively assess haemodynamic characteristics of brain tissue. We investigated if different brain tumor types can be distinguished from each other using Patlak analysis of PCT data. PCT data from 43 patients with brain tumours were analysed with a commercial implementation of the Patlak method. Four patients had low-grade glioma (WHO II), 31 patients had glioblastoma (WHO IV) and eight patients had intracerebral lymphoma. Tumour regions of interest (ROIs) were drawn in a morphological image and automatically transferred to maps of cerebral blood flow (CBF), cerebral blood volume (CBV) and permeability (K Trans). Mean values were calculated, group differences were tested using Wilcoxon and Mann Whitney U-tests. In comparison with normal parenchyma, low-grade gliomas showed no significant difference of perfusion parameters (p > 0.05), whereas high-grade gliomas demonstrated significantly higher values (p Trans, p Trans values compared with unaffected cerebral parenchyma (p = 0.0078) but no elevation of CBV. High-grade gliomas show significant higher CBV values than lymphomas (p = 0.0078). PCT allows to reliably classify gliomas and lymphomas based on quantitative measurements of CBV and K Trans. (orig.)

  8. Future of functional brain imaging

    International Nuclear Information System (INIS)

    To examine the living human brain's sensory, motor and cognitive interactions and to understand how activities in anatomically distinct neural processing regions are orchestrated to perform complex tasks represents a future challenge to neuroscientists. Until recently, functional brain imaging data have been constrained by the severely limited spatial (5-15 mm) and temporal resolution (from a few seconds to minutes) of the nuclear medicine methods, single-photon emission tomography (SPET) and positron emission tomography (PET). The advent of new non-invasive, fast imaging methods - functional magnetic resonance imaging (fMRI), serial X-ray computed tomography ('cine' CT) and magnetoencephalography (MEG) - has created a need for a survey to compare these techniques with conventional SPET and PET. Each technique has unique advantages and simultaneously serious limitations. No method has achieved a clear supremacy in functional brain imaging. (orig.)

  9. Auditory brain-stem response, CT and MR imaging in a family with classical type Pelizaeus-Merzbacher Disease

    International Nuclear Information System (INIS)

    A family in which 5 males in successive generations were clinically suspected to be affected with the classical X-linked recessive form of Pelizaeus-Merzbacher disease (PMD) is presented. Two brothers and their maternal uncle were examined by one of the author (MS). In two brothers, aged 3 years and 2 years, the disease became obvious within a month after birth with nystagmus and head tremor. Head control and sitting were achieved at the age of 18 months at which time they began to speak. They could not stand nor walk without support. They had dysmetria, weakness and hyper-reflexia of lower extremities, and mild mental retardation. Their maternal uncle, aged 37 years, showed psychomotor retardation from birth and subsequently developed spastic paraplegia. He had been able to walk with crutches until adolescence. He had dysmetria, scanning speech, athetoid posture of fingers and significant intellectual deficits. Auditory brainstem response in both brothers revealed well defined waves I and II, low amplitude wave III and an absence of all subsequent components. CT demonstrated mild cerebral atrophy in the elder brother and was normal in the younger brother, but in their uncle, CT showed atrophy of the brainstem, cerebellum and cerebrum, and low density of the white matter of the centrum semiovale. MRI was performed in both brothers. Although the brainstem, the internal capsule and the thalamus were myelinated, the myelination in the subcortical white matter was restricted to periventricular regions on IR sequence scans. On SE sequence, the subcortical white matter was imaged as a brighter area than the cerebral cortex. These results demonstrate that the degree of myelination in these patients was roughly equal to that of 3-to 6-month old infants. (J.P.N.)

  10. Auditory brain-stem response, CT and MR imaging in a family with classical type Pelizaeus-Merzbacher Disease

    Energy Technology Data Exchange (ETDEWEB)

    Shiomi, M.; Ookuni, H.; Sugita, T.

    1987-05-01

    A family in which 5 males in successive generations were clinically suspected to be affected with the classical X-linked recessive form of Pelizaeus-Merzbacher disease (PMD) is presented. Two brothers and their maternal uncle were examined by one of the authors (MS). In two brothers, aged 3 years and 2 years, the disease became obvious within a month after birth with nystagmus and head tremor. Head control and sitting were achieved at the age of 18 months at which time they began to speak. They could not stand nor walk without support. They had dysmetria, weakness and hyper-reflexia of lower extremities, and mild mental retardation. Their maternal uncle, aged 37 years, showed psychomotor retardation from birth and subsequently developed spastic paraplegia. He had been able to walk with crutches until adolescence. He had dysmetria, scanning speech, athetoid posture of fingers and significant intellectual deficits. Auditory brainstem response in both brothers revealed well defined waves I and II, low amplitude wave III and an absence of all subsequent components. CT demonstrated mild cerebral atrophy in the elder brother and was normal in the younger brother, but in their uncle, CT showed atrophy of the brainstem, cerebellum and cerebrum, and low density of the white matter of the centrum semiovale. MRI was performed in both brothers. Although the brainstem, the internal capsule and the thalamus were myelinated, the myelination in the subcortical white matter was restricted to periventricular regions on IR sequence scans. On SE sequence, the subcortical white matter was imaged as a brighter area than the cerebral cortex. These results demonstrate that the degree of myelination in these patients was roughly equal to that of 3-to 6-month old infants.

  11. 基于MATLAB的脑CT图像三维重建研究%Three Dimensional Reconstruction of Brain CT Image Based on MATLAB

    Institute of Scientific and Technical Information of China (English)

    裴智军; 高关心; 谢伟

    2015-01-01

    目的:对脑CT图像进行三维重建研究,提供具有真实感的三维图形,便于在临床诊断、手术规划及医学教学演示等方面应用。方法:通过MATLAB语言计算平台,采用体绘制法,实现脑部CT图像医学图像预处理、体数据集构造及三维重构、显示的全过程。结果:采用CT薄层扫描资料建立起来的三维模型,形态逼真,能真实反映头颅外形及三维结构。结论:基于MATLAB的脑CT图像三维重建实现方式显示效果良好,计算速度快,便于掌握,为医学图像的三维可视化技术提供了一种新的可能。%Objective: To study focused on three dimensional reconstruction of brain CT images, which can provide realistic three dimensional graphics to users, also can be applied in areas such as medical diagnosing, surgery planning and teaching demonstration. Methods: This paper introduces a method of three dimensional reconstruction using volume rendering method based on MATLAB computing platform. The whole procedure of medical images process, three dimensional data creation, three dimensional reconstruction and display with this method are described. Results:The three dimensional model reconstructed by CT scan data can reflect the external form and three dimensional structure of head objectively. Conclusion:The brain CT image reconstruction based on MATLAB shows good results, fast and easy for users to learn. As a result, a new possibility for three dimensional visualization of medical image is put forward.

  12. Imaging of cerebritis, encephalitis, and brain abscess.

    Science.gov (United States)

    Rath, Tanya J; Hughes, Marion; Arabi, Mohammad; Shah, Gaurang V

    2012-11-01

    Imaging plays an important role in the diagnosis and treatment of brain abscess, pyogenic infection, and encephalitis. The role of CT and MRI in the diagnosis and management of pyogenic brain abscess and its complications is reviewed. The imaging appearances of several common and select uncommon infectious encephalitides are reviewed. Common causes of encephalitis in immunocompromised patients, and their imaging appearances, are also discussed. When combined with CSF, serologic studies and patient history, imaging findings can suggest the cause of encephalitis. PMID:23122258

  13. Automated movement correction for dynamic PET/CT images: Evaluation with phantom and patient data

    OpenAIRE

    Ye, H.; Wong, KP; Wardak, M; Dahlbom, M.; Kepe, V; Barrio, JR; Nelson, LD; Small, GW; Huang, SC

    2014-01-01

    Head movement during a dynamic brain PET/CT imaging results in mismatch between CT and dynamic PET images. It can cause artifacts in CT-based attenuation corrected PET images, thus affecting both the qualitative and quantitative aspects of the dynamic PET images and the derived parametric images. In this study, we developed an automated retrospective image-based movement correction (MC) procedure. The MC method first registered the CT image to each dynamic PET frames, then re-reconstructed th...

  14. Comparative study of cerebral blood perfusion SPECT imaging and CT scan in evaluation of the curative effect of hyperbaric oxygen in patients with post-traumatic brain syndrome

    International Nuclear Information System (INIS)

    Objective: To comparatively study the results of cerebral SPECT and cerebral CT before and after hyperbaric oxygen (HBO) treatment in post-traumatic brain syndrome. Methods: HBO was used to treat 288 patients with post-traumatic brain syndrome for two courses, and made therapeutic surveillance and comparative analysis with 99Tcm-ECD SPECT, CT before and after treatment. Results: Before treatment, the positive rate of cerebral SPECT was 80.6%, but the positive rate of CT was only 10.2%; after treatment, 90% of SPECT became negative, and the clinical symptoms of the patients disappeared as SPECT became negative. The results showed that HBO treatment could evidently improve rCBF, and showed that SPECT was superior to CT in surveillance of HBO treatment. Conclusions: 99Tcm-ECD SPECT could play an important role in the diagnosis of post-traumatic brain syndrome and the therapeutic surveillance of HBO

  15. Brain perfusion CT in acute stroke: current status

    International Nuclear Information System (INIS)

    Dynamic perfusion CT has become a widely accepted imaging modality for the diagnostic workup of acute stroke patients. Although compared with standard spiral CT the use of multislice CT has broadened the range from which perfusion data may be derived in a single scan run. The advent of multidetector row technology has not really overcome the limited 3D capability of this technique. Multidetector CT angiography (CTA) of the cerebral arteries may in part compensate for this by providing additional information about the cerebrovascular status. This article describes the basics of cerebral contrast bolus scanning with a special focus on optimization of contrast/noise in order to ensure high quality perfusion maps. Dedicated scan protocols including low tube voltage (80 kV) as well as the use of highly concentrated contrast media are amongst the requirements to achieve optimum contrast signal from the short bolus passage through the brain. Advanced pre and postprocessing algorithms may help reduce the noise level, which may become critical in unconscious stroke victims. Two theoretical concepts have been described for the calculation of tissue perfusion from contrast bolus studies, both of which can be equally employed for brain perfusion imaging. For each perfusion model there are some profound limitations regarding the validity of perfusion values derived from ischemic brain areas. This makes the use of absolute quantitative cerebral blood flow (CBF) values for the discrimination of the infarct core from periinfarct ischemia questionable. Multiparameter imaging using maps of CBF, cerebral blood volume (CBV), and a time parameter of the local bolus transit enables analyzing of the cerebral perfusion status in detail. Perfusion CT exceeds plain CT in depicting cerebral hypoperfusion at its earliest stage yielding a sensitivity of about 90% for the detection of embolic and hemodynamic lesions within cerebral hemispheres. Qualitative assessment of brain perfusion can be

  16. Permeability imaging in pediatric brain tumors

    OpenAIRE

    Lam, Sandi; Lin, Yimo; Warnke, Peter C.

    2014-01-01

    While traditional computed tomography (CT) and magnetic resonance (MR) imaging illustrate the structural morphology of brain pathology, newer, dynamic imaging techniques are able to show the movement of contrast throughout the brain parenchyma and across the blood-brain barrier (BBB). These data, in combination with pharmacokinetic models, can be used to investigate BBB permeability, which has wide-ranging applications in the diagnosis and management of central nervous system (CNS) tumors in ...

  17. Brain imaging and schizophrenia

    International Nuclear Information System (INIS)

    Brain structures and brain function have been investigated by the new brain imaging techniques for more than ten years. In Psychiatry, these techniques could afford a new understanding of mental diseases. In schizophrenic patients, CAT scanner and RMI pointed out statistically significant ventricular enlargments which are presently considered as evidence for abnormalities in brain maturation. Functional imaging techniques reported metabolic dysfunctions in the cortical associative areas which are probably linked to the cognitive features of schizophrenics

  18. CT-guided stereotactic brain surgery

    International Nuclear Information System (INIS)

    An apparatus for stereotactic brain surgery combined with a whole-body CT scanner, by which surgery can be performed by CT scanning, was developed. This apparatus and an Archimedes screw were clinically applied to surgery for removal of deep-seated intracranial hematomas, and satisfactory results were obtained. An outline of this apparatus is given, and combined use of the apparatus and the Secta type of ultrasound apparatus for monitoring surgery is described. (Namekawa, K.)

  19. 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

  20. CT imaging of the pancreas

    International Nuclear Information System (INIS)

    Full text: Introduction: CT is the method of choice for differential and preoperative diagnosis of the pancreatic diseases. This presentation will be presented main CT imaging characteristics of the most common pancreatic diseases, as well as the advantages, disadvantages and indications for conducting of a computer imaging study of the pancreatic diseases. What you will learn: To know and to describe the main nosological units ( tumors and pancreatitis) affecting the pancreas; How to distinguish benign from malignant lesions of the pancreas; To know benign pancreatic diseases that mimic malignancy; Advantages and limitations of CT in diagnosing of the pancreatic diseases, Correctly interpretation and clear description of imaging findings in pancreatic diseases for the purposes of subsequent conservative or surgery treatment, To assess the need to carry out further research and control studies. Discussion: CT study makes possible the presentation of the feature density structure, limits and the contrasting of pathological changes in the pancreas, their anatomical position in it and the position toward the neighboring structures. CT provides information for the vascularisation of the described lesions by the mode of change in the post-contrast stenograms density. CT is an indispensable method for preoperative assessment of the anatomical course of blood vessels and vascular invasion in tumor diseases. CT is a valuable tool in the differential diagnosis between solid malignant (adenocarcinoma, neuroendocrine tumors, lymphoma, metastasis) and benign nosological entities such as certain forms of pancreatitis (autoimmune, paraduodenal) between benign and malignant pancreatic cystic lesions, etc. Conclusion: CT is an essential method in the diagnostic algorithm of pancreatic diseases due to continuous improvement and the possibility to meet the ever more questions in one-step assay

  1. Brain tumors imaging

    International Nuclear Information System (INIS)

    At the beginning of the illness, we should use an anatomical technique for brain exploration (CT scan or MRI) to see the boundaries of the lesion before the diagnostic biopsy. After treatment (chemotherapy and/or radiotherapy and/or surgery), the evolution of the lesion can be observed with functional techniques (SPECT Thallium or MIBI or PET scan). (author)

  2. CT evaluation of choriocarcinoma with brain metastases

    International Nuclear Information System (INIS)

    It is well established that the computed tomography(CT) is an essential part not only in screening primary brain tumors, but also in staging known malignancy. This paper reports various CT findings demonstrated in 12 cases of choriocarcinoma with brain metastasis. The CT findings such as the number, location and density of the metastatic lesions, the degree of brain edema, mass effect and effect of contrast enhancement are reviewed as well as the episode of stroke syndrome and survival duration after neurologic symptom attacks. The results were as follows: 1. The of these cases showed solitary metastatic lesion and remaining 2 cases were multiple lesions. 2. One was isodense density and the others were hemorrhagic increased density by CT. 3. All of these showed mass effect to the surrounding structures along with moderate to marked brain edema. 4. The position of the metastatic lesion were located at the supratentorially in all cases. Most of them were at the unilateral frontal or parietal area or both of them. One which noted multiple metastatic foci showed at the bilateral occipital regions. 5. Nine cases showed ring enhancement after contrast infusion. One which noted isodense density on the noninfusion scan showed also ring enhancement after contrast infusion. 6. Nine cases showed positive stroke syndrome. One of them was performed emergency craniotomy. The remaining 3 cases noted progressive neurologic symptoms. 7. Two cases were noted only brain metastasis but the others also had various degree of pulmonary metastasis and 2 of latter had hepatic metastasis, too. 8. Most of the cases were treated with CHAMOCA regimen, and one of them was taken whole brain irradiation (3000 rads/2 weeks). Another on case revealed marked regression of not only metastatic brain lesion but the pulmonary lesion after the 8th course of CHAMOCA regimen and still alive for over 460 days

  3. CT evaluation of choriocarcinoma with brain metastases

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, Sei Chul; Kim, Choon Yul; Kwon, Hyung Chul; Bahk, Young Whee; Kim, Seung Jo [Catholic Medical College, Seoul (Korea, Republic of)

    1984-03-15

    It is well established that the computed tomography(CT) is an essential part not only in screening primary brain tumors, but also in staging known malignancy. This paper reports various CT findings demonstrated in 12 cases of choriocarcinoma with brain metastasis. The CT findings such as the number, location and density of the metastatic lesions, the degree of brain edema, mass effect and effect of contrast enhancement are reviewed as well as the episode of stroke syndrome and survival duration after neurologic symptom attacks. The results were as follows: 1. The of these cases showed solitary metastatic lesion and remaining 2 cases were multiple lesions. 2. One was isodense density and the others were hemorrhagic increased density by CT. 3. All of these showed mass effect to the surrounding structures along with moderate to marked brain edema. 4. The position of the metastatic lesion were located at the supratentorially in all cases. Most of them were at the unilateral frontal or parietal area or both of them. One which noted multiple metastatic foci showed at the bilateral occipital regions. 5. Nine cases showed ring enhancement after contrast infusion. One which noted isodense density on the noninfusion scan showed also ring enhancement after contrast infusion. 6. Nine cases showed positive stroke syndrome. One of them was performed emergency craniotomy. The remaining 3 cases noted progressive neurologic symptoms. 7. Two cases were noted only brain metastasis but the others also had various degree of pulmonary metastasis and 2 of latter had hepatic metastasis, too. 8. Most of the cases were treated with CHAMOCA regimen, and one of them was taken whole brain irradiation (3000 rads/2 weeks). Another on case revealed marked regression of not only metastatic brain lesion but the pulmonary lesion after the 8th course of CHAMOCA regimen and still alive for over 460 days.

  4. In vivo microCT imaging of rodent cerebral vasculature

    International Nuclear Information System (INIS)

    Computed tomography (CT) remains a critical diagnostic tool for evaluating patients with cerebrovascular disease, and the advent of specialized systems for imaging rodents has extended these techniques to small animal models of these diseases. We therefore have evaluated in vivo methods of imaging rat models of hemorrhagic stroke using a high resolution compact computed tomography ('microCT') system (FLEX(tm) X-O(tm), Gamma Medica-Ideas, Northridge, CA). For all in vivo studies, the head of the anesthetized rat was secured in a custom immobilization device for microCT imaging with 512 projections over 2 min at 60 kVp and 0.530 mA (Itube x t/rotation = 63.6 mAs). First, imaging without iodinated contrast was performed (a) to differentiate the effect of contrast agent in contrast-enhanced CT and (b) to examine the effectiveness of the immobilization device between two time points of CT acquisitions. Then, contrast-enhanced CT was performed with continuous administration of iopromide (300 mgI ml-1 at 1.2 ml min-1) to visualize aneurysms and other vascular formations in the carotid and cerebral arteries that may precede subarachnoid hemorrhage. The accuracy of registration between the noncontrast and contrast-enhanced CT images with the immobilization device was compared against the images aligned with normalized mutual information using FMRIB's linear image registration tool (FLIRT). Translations and rotations were examined between the FLIRT-aligned noncontrast CT image and the nonaligned noncontrast CT image. These two data sets demonstrated translational and rotational differences of less than 0.5 voxel (∼85 μm) and 0.5 deg., respectively. Noncontrast CT demonstrated a very small volume (0.1 ml) of femoral arterial blood introduced surgically into the rodent brain. Continuous administration of iopromide during the CT acquisition produced consistent vascular contrast in the reconstructed CT images. As a result, carotid arteries and major cerebral blood vessels

  5. In vivo microCT imaging of rodent cerebral vasculature

    Energy Technology Data Exchange (ETDEWEB)

    Seo, Youngho; Hasegawa, Bruce H [Center for Molecular and Functional Imaging, Department of Radiology, University of California, San Francisco, CA 94143 (United States); Hashimoto, Tomoki; Nuki, Yoshitsugu [Center for Cerebrovascular Research, Department of Anesthesia and Perioperative Care, University of California, San Francisco, CA 94143 (United States)], E-mail: youngho.seo@radiology.ucsf.edu

    2008-04-07

    Computed tomography (CT) remains a critical diagnostic tool for evaluating patients with cerebrovascular disease, and the advent of specialized systems for imaging rodents has extended these techniques to small animal models of these diseases. We therefore have evaluated in vivo methods of imaging rat models of hemorrhagic stroke using a high resolution compact computed tomography ('microCT') system (FLEX(tm) X-O(tm), Gamma Medica-Ideas, Northridge, CA). For all in vivo studies, the head of the anesthetized rat was secured in a custom immobilization device for microCT imaging with 512 projections over 2 min at 60 kVp and 0.530 mA (I{sub tube} x t/rotation = 63.6 mAs). First, imaging without iodinated contrast was performed (a) to differentiate the effect of contrast agent in contrast-enhanced CT and (b) to examine the effectiveness of the immobilization device between two time points of CT acquisitions. Then, contrast-enhanced CT was performed with continuous administration of iopromide (300 mgI ml{sup -1} at 1.2 ml min{sup -1}) to visualize aneurysms and other vascular formations in the carotid and cerebral arteries that may precede subarachnoid hemorrhage. The accuracy of registration between the noncontrast and contrast-enhanced CT images with the immobilization device was compared against the images aligned with normalized mutual information using FMRIB's linear image registration tool (FLIRT). Translations and rotations were examined between the FLIRT-aligned noncontrast CT image and the nonaligned noncontrast CT image. These two data sets demonstrated translational and rotational differences of less than 0.5 voxel ({approx}85 {mu}m) and 0.5 deg., respectively. Noncontrast CT demonstrated a very small volume (0.1 ml) of femoral arterial blood introduced surgically into the rodent brain. Continuous administration of iopromide during the CT acquisition produced consistent vascular contrast in the reconstructed CT images. As a result, carotid

  6. CT number variations in micro CT imaging systems

    Science.gov (United States)

    Tu, Shu-Ju; Hsieh, Hui-Ling; Chao, Tsi-Chian

    2008-03-01

    CT numbers can be directly computed from the linear attenuation coefficients in the reconstructed CT images and are correlated to the electron densities of the chemical elements with specific atomic numbers. However, the computed CT numbers can be varied when different imaging parameters are used. Phantoms composed of clinically relevant and tissue-equivalent materials (lung, bone, muscle, and adipose) were scanned with a commercial circular-scanning micro CT imager. This imaging system is composed with a micro-focused x-ray tube and charged-coupled device (CCD) camera as the detector. The mean CT numbers and the corresponding standard deviations in terms of Hounsfield units were then computed from a pre-defined region of interest located within the reconstructed volumetric images. The variations of CT number were then identified from a series of imaging parameters. Those parameters include imaging acquisition modes (e.g., the metal filter used in the x-ray tube), reconstruction methods (e.g., Feldkamp and iterative algorithm), and post-image processing techniques (e.g., ring artifact, beam-hardening artifact, and smoothing processing). These variations of CT numbers are useful and important in tissue characterization, quantitative bone structure analysis, bone marrow density evaluation, and Monte Carlo dose calculations for the pilot small animal study when micro CT imaging systems are employed. Also these variations can be used as the quantification for the performance of the micro CT imaging systems.

  7. Tumor hypoxia and microscopic diffusion capacity in brain tumors: A comparison of 62Cu-Diacetyl-Bis (N4-Methylthiosemicarbazone) PET/CT and diffusion-weighted MR imaging

    International Nuclear Information System (INIS)

    The aim of this study was to clarify the relationship between tumor hypoxia and microscopic diffusion capacity in primary brain tumors using 62Cu-Diacetyl-Bis (N4-Methylthiosemicarbazone) (62Cu-ATSM) PET/CT and diffusion-weighted MR imaging (DWI). This study was approved by the institutional human research committee and was HIPAA compliant, and informed consent was obtained from all patients. 62Cu-ATSM PET/CT and DWI were performed in a total of 40 primary brain tumors of 34 patients with low grade glioma (LGG, n = 13), glioblastoma (GBM, n = 20), and primary central nervous system lymphoma (PCNSL, n = 7). 62Cu-ATSM PET/CT parameters and apparent diffusion coefficient (ADC) obtained by DWI were compared. High intensity signals by 62Cu-ATSM PET/CT and DWI in patients with GBM and PCNSL, and low intensity signals in LGG patients were observed. An inverse correlation was found between maximum SUV (SUVmax) and minimum ADC (ADCmin) (r = -0.583, p ratio) and ADCmin for all tumors (r = -0.532, p max and T/Bratio in GBM were higher than LGG (p min was lower in GBM (p = 0.011) and PCNSL (p = 0.01) than in LGG, while no significant difference was found between GBM and PCNSL (p = 0.90). Tumor hypoxia assessed by 62Cu-ATSM PET/CT correlated with microscopic diffusion capacity obtained by DWI in brain tumors. Both 62Cu-ATSM PET/CT and DWI were considered feasible imaging methods for grading glioma. However, 62Cu-ATSM PET/CT provided additional diagnostic information to differentiate between GBM and PCNSL. (orig.)

  8. Development of the robot system to assist CT-guided brain surgery

    International Nuclear Information System (INIS)

    The robot technology was introduced into the stereotactic neurosurgery for application to biopsy, blind surgery, and functional neurosurgery. The authors have developed a newly designed the robot system to assist CT-guided brain surgery, designed to allow a biopsy needle to reach the targget such as a cerebral tumor within a brain automatically on the basis of the X,Y, and Z coordinates obtained by CT scanner. In this paper we describe construction of the robot, the control of the robot by CT image, robot simulation, and investigated a phantom experiment using CT image. (author)

  9. Computed tomographic imaging of the brain of normal neonatal foals

    Directory of Open Access Journals (Sweden)

    L Cabrera

    2015-01-01

    Full Text Available The aim of this study was to provide a more complete description of normal cross-sectional anatomy of the neonatal brain of the foal and associated structures by computed tomography (CT and gross anatomical sections. Using a fourth-generation CT scanner, 2-mm contiguous transverse images were acquired from two neonatal 5-days-old Quarter horse foals. After the study the animals were euthanised for reasons unrelated to head pathology. To assist in the accurate identification of brain and associated structures, transverse CT images were obtained and compared with the corresponding frozen cross-sections of the head. CT images matched well with their corresponding transverse gross sections and provided good differentiation between the bones and the soft tissues of the head. These CT images are intended to be a useful initial anatomic reference in the interpretation for clinical CT imaging studies of the brain and associated structures in live neonatal foals.

  10. Prediction of stroke thrombolysis outcome using CT brain machine learning

    Directory of Open Access Journals (Sweden)

    Paul Bentley

    2014-01-01

    Full Text Available A critical decision-step in the emergency treatment of ischemic stroke is whether or not to administer thrombolysis — a treatment that can result in good recovery, or deterioration due to symptomatic intracranial haemorrhage (SICH. Certain imaging features based upon early computerized tomography (CT, in combination with clinical variables, have been found to predict SICH, albeit with modest accuracy. In this proof-of-concept study, we determine whether machine learning of CT images can predict which patients receiving tPA will develop SICH as opposed to showing clinical improvement with no haemorrhage. Clinical records and CT brains of 116 acute ischemic stroke patients treated with intravenous thrombolysis were collected retrospectively (including 16 who developed SICH. The sample was split into training (n = 106 and test sets (n = 10, repeatedly for 1760 different combinations. CT brain images acted as inputs into a support vector machine (SVM, along with clinical severity. Performance of the SVM was compared with established prognostication tools (SEDAN and HAT scores; original, or after adaptation to our cohort. Predictive performance, assessed as area under receiver-operating-characteristic curve (AUC, of the SVM (0.744 compared favourably with that of prognostic scores (original and adapted versions: 0.626–0.720; p < 0.01. The SVM also identified 9 out of 16 SICHs, as opposed to 1–5 using prognostic scores, assuming a 10% SICH frequency (p < 0.001. In summary, machine learning methods applied to acute stroke CT images offer automation, and potentially improved performance, for prediction of SICH following thrombolysis. Larger-scale cohorts, and incorporation of advanced imaging, should be tested with such methods.

  11. PET/CT脑成像新药研究发展趋势及基于PET/CT设备的脑成像新药研发%R & D Trends of New Drugs for PET/CT Brain Imaging and R & D of New Drugs for Brain Imaging Based on the PET/CT System

    Institute of Scientific and Technical Information of China (English)

    周克迪; 王贺宁; 李素莹; 孟祥溪; 孙红芳; 任秋实

    2015-01-01

    Brain molecular imaging plays an important role in investigations on the function of brain and mechanism of neural diseases. The dopaminergic receptor system is closely related with emotion, love, addiction, incentives, many diseases and disorders. Hereby, taking 18F-fallypride as an example of novel dopamine receptor D2/D3 probes visualizing the Dopamine D2/D3 receptors in striatal and extra-striatal areas, this paper reviews the trends of R&D(Research and Development) and clinical applications of 18F-fallypride, and investigates 18F-fallypride with 15 healthy volunteers’ brain imaging by using the self-innovated AMIC Ray-Scan 64 PET/CT. The result shows a homogeneous and symmetrical distribution of signal in striatal and extra-striatal areas, indicating that the 18F-fallypride, as well as Ray-Scan 64 PET/CT, has demonstrated an excellent performance in dopamine receptor imaging. Additionally, this paper also reviews the progress of clinical uses of 18F-ML-10, a molecular probe to visualize apoptosis. Besides, 10 patients with brain tumorsare investigated by 18F-ML-10-PET/CT imaging pre-and post-radiation with AMIC Ray-Scan 64 PET/CT, in order to evaluate the effect of treatments.%脑部分子影像对于脑功能和神经疾病发病机理研究以及早期诊断有重大意义,多巴胺受体系统与人的情绪、爱情、成瘾、奖励机制和一些疾病有重要的联系。本文以新型脑神经多巴胺受体D2/D3显像剂18F-fallypride为例,探讨了18F-fallypride的研究发展和应用趋势,并应用自主研发的AMIC Ray-Scan 64 PET/CT成像系统对15例健康志愿者进行了临床研究,图像上观测到纹状体和外纹状体的信号清晰,药物分布均匀、对称。此外,脑肿瘤细胞凋亡显像剂18F-ML-10新药可对脑肿瘤的放射性治疗效果进行评估,本文综述了18F-ML-10临床应用的发展,并对10例脑瘤患者接受放射性治疗前后的细胞凋亡情况进行了对比评估,并通过

  12. Analysis of risk factor of unfavorable outcome in patients with diffuse brain injury from clinical, CT and magnetic resonance imaging findings

    International Nuclear Information System (INIS)

    We performed a statistical investigation of poor outcome factors for diffuse brain injury using the state of consciousness, age, gender, pupil abnormality, CT, and MRI findings upon arrival of diffuse brain injury patients to the hospital. We studied 93 diffuse brain injury patients but excluded those with multiple trauma of AIS 3 or above, those who tested positive for alcohol at the time of arrival at the hospital, and those who also exhibited a focal brain injury. Based on clinical findings made at the time patients arrived at the hospital, being older than 65 years of age, Glasgow coma scale (GCS) 7 and below, and having abnormal light reflexes were poor outcome factors. Regarding CT findings, being unable to see the suprasellar cistern, poor visualization of the ambient cistern, and subarachnoid hemorrhage (SAH) on the brain surface were poor outcome factors. Regarding MRI findings, the presence of basal ganglia injury and brainstem injury were poor outcome factors. Based on a stepwise logistic regression analysis of all poor outcome factors, it was revealed that being older than 65 years of age, having light reflex abnormalities, and the existence of brainstem injuries are all poor outcome factors, independent of each other. In addition, regarding injuries to the brain stem, midbrain injuries were the most prevalent and lateral injuries of the midbrain was the most prevalent poor outcome factor. However, in cases of injury to the brainstem only, recovery was good. (author)

  13. Influence of CT/MRI Fusion Image on Target Volume and 3-D Conformal Radiotherapy in Non-small Cell Lung Cancer with Brain Metastasis%CT/MRI诊断影像融合对非小细胞肺癌脑转移瘤靶区及三维适形治疗影响

    Institute of Scientific and Technical Information of China (English)

    杨金山; 魏永兵; 侯超; 李静; 朱瑞霞

    2014-01-01

    目的:比较CT图像和CT/MRI融合图像来源的肺癌脑转移肿瘤靶区,评价CT/MRI融合靶区容积应用于三维适形放射治疗时,对治疗剂量的影响。方法:将20例非小细胞肺癌脑转移患者的增强CT和MRI扫描的图像传送至图像处理工作站,在CT和CT/MRI融合图像上分别勾画GTV和周围重要的器官。每个病例分别在CT图像和CT/MRI融合图像都做1个三维适形放射治疗计划。肿瘤的处方剂量为60 Gy,比较2个治疗计划中肿瘤靶区的95%容积(D95)受照平均剂量、周围正常组织的5%容积(D5)受照平均剂量。结果:CT/MRI融合图像上的肿瘤靶区平均比CT上的肿瘤靶区大21.32%。用CT上勾画的靶区有一部分肿瘤处于低剂量区,CT/MRI融合图像上的靶区D95剂量分布较好,但在周围重要器官的剂量分布较高。结论:CT/MRI融合图像有助于靶区的确定,在三维适形放射治疗计划上的肿瘤靶区剂量分布足够,能提高靶区勾画的准确性,更利于精确放疗的实施。%Objective:To compare the CT images and CT/MRI images fusion sources of lung cancer with brain metastasis tumor target,and to evaluae the effects of dose for treatment on target volume CT/MRI fusion for three-dimensional conformal radiotherapy. Method:The enhancement CT and MRI scan image of 20 patients with brain metastases from non-small cell lung cancer was transfer to image processing workstation,GTV and surrounding vital organs on CT and CT/MRI images fusion was delineated respectively. A three-dimensional conformal radiotherapy plan was done in CT images and CT/MRI fusion images of ach case. Tumor prescription dose was 60 Gy. Compared the average dose of the 95%volume(D95)tumor target,the average dose of the 5%of the normal tissue around of the two treatment plans. Result:The tumor targets of the CT/MRI images fusion was greater than those of the CT tumor targets on average 21.32%. A part of the tumor was

  14. The role of MRI and CT of the brain in first episodes of psychosis

    International Nuclear Information System (INIS)

    Aim: To investigate whether imaging is associated with early detection of the organic causes of the first episode of psychosis (FEP). Materials and methods: Individuals with FEP but no neurological signs referred to a tertiary centre for cerebral magnetic resonance imaging (MRI) or computed tomography (CT) were reviewed retrospectively. Two groups were evaluated with either CT or MRI; the two groups were independent and no individual underwent both CT and MRI. Results: One hundred and twelve consecutive cerebral MRI and 204 consecutive CT examinations were identified. Three (2.7%) individuals had brain lesions [brain tumour and human immunodeficiency virus (HIV) encephalopathy] potentially accountable for the psychosis at MRI. Seventy patients (62.5%) had incidental brain lesions, such as cerebral atrophy, small vessel ischaemic changes, unruptured Circle of Willis aneurysm, cavernoma, and arachnoid cysts at MRI. Three patients (1.5%) had focal brain lesions (primary or secondary tumours) potentially accountable for the psychosis at CT. One hundred and thirty-three patients (65.2%) had incidental brain lesions unrelated to the psychosis on CT scan. There was no significant difference between MRI and CT imaging in detecting organic disease potentially responsible for FEP (p < 0.001). Conclusion: Routine MRI or CT imaging of the brain is unlikely to reveal disease leading to a significant change in management. MRI was comparable with CT in terms of diagnosis of both pathological and incidental cerebral lesions. Therefore, routine brain structural imaging of FEP in patients without focal neurology may not be routinely required and if imaging is requested then CT may function equally as well as MRI as the first-line investigation

  15. A study of whole brain perfusion CT and CT angiography in hyperacute and acute cerebral infarction

    International Nuclear Information System (INIS)

    Objective: To evaluate the diagnostic value of whole-brain perfusion blood volume-weighted CT imaging (PWCT) and simultaneous CT angiography (CTA) on early stage of cerebral ischemic infarction. Methods: Non-contrast CT (NCCT), CT perfusion-weighted imaging (PWCT) and delayed CT (DCT) were conducted on 20 cases of early ischemic infarction of whose onset time ranged from 2 to 24 hours. All cases were reexamined with CT or MRI one week to one month later. CT values and perfusion blood volume (PBV) of central and peripheral low perfusion areas as well as those of collateral side were measured. CTA was reconstructed with PWCT as source images to evaluate occlusion or stenosis of blood vessel, and DCT was used to detect the collateral circulation. Results: Of the 20 cases, NCCT, PWCT and CTA were negative in 10 cases in which 6 were confirmed as Transient Ischemic Attack (TIA) on reexamined CT and clinical features, and the other 4 were confirmed as lacunar infarction. For the remaining 10 cases, a comparison was made with ANOVA between low perfusion area (central, peripheral inside and outside) and collateral side. The difference was significant (P<0.01). However, no significant difference was revealed in the central, peripheral inside and outside areas. PBV values were significant in low perfusion area and collateral side (P<0.05). The area of the final infarction was larger than that of the low perfusion area, and the percentage of enlargement exhibited medium negative correlation to the time of ischemia. CTA indicated that 2 cases suffered from left middle cerebral artery occlusion, meanwhile anterior and middle branches of MCA in the other 3 cases were not identified. The sensitivity of NCCT, PWCT and CTA were 28.5%, 71.4% and 35.7% respectively. DCT indicated that 5 cases had asymmetrical blood vessels. Conclusion: The whole-brain perfusion-weighted CT imaging and simultaneous CT angiography (CTA) is p roved to be a simple, timesaving and effective method for the

  16. Human brain imaging

    International Nuclear Information System (INIS)

    Just as there have been dramatic advances in the molecular biology of the human brain in recent years, there also have been remarkable advances in brain imaging. This paper reports on the development and broad application of microscopic imaging techniques which include the autoradiographic localization of receptors and the measurement of glucose utilization by autoradiography. These approaches provide great sensitivity and excellent anatomical resolution in exploring brain organization and function. The first noninvasive external imaging of receptor distributions in the living human brain was achieved by positron emission tomography (PET) scanning. Developments, techniques and applications continue to progress. Magnetic resonance imaging (MRI) is also becoming important. Its initial clinical applications were in examining the structure and anatomy of the brain. However, more recent uses, such as MRI spectroscopy, indicate the feasibility of exploring biochemical pathways in the brain, the metabolism of drugs in the brain, and also of examining some of these procedures at an anatomical resolution which is substantially greater than that obtainable by PET scanning. The issues will be discussed in greater detail

  17. Disappearance of enhancement of brain tumor in contrast CT scan after excessively high dosage of dexamethasone

    International Nuclear Information System (INIS)

    The method of steroid administration was studied as suggested by CT findings in 5 cases of brain tumor. In the CT image 72 hours after administration of dexamethasone 96 mg/d, contrast enhancement (CE) disappeared nearly completely in 3 cases of malignant glioma, and the indentification of tumor image on CT became difficult. Two cases of pinealoblastoma and low grade astrocytoma, respectively, showed only a little decrease of CE. From the CT images of 201 cases, the correlation between peritumoral edema and CE was that both were strong in glioblastoma, the former stronger in metastatic brain tumor, the latter stronger in meningioma, and both weak in low grade glioma and medulloblastoma. Steroid administration is indicated in tumors supposed to have little vascular pooling and strong extravascular accumulation of a contrast medium from the mechanism of CE in CT, and marked suppression of permeability with excessively high dosage seems to be noted as the change of CT findings. (J.P.N.)

  18. CT Imaging: Basics and New Trends

    Science.gov (United States)

    Peyrin, Françoise; Engelke, Klaus

    This chapter presents the principle of X-ray CT and its evolution during the last 40 years. The first section describes the physical basis of X-ray CT, tomographic image reconstruction algorithms, and the source of artifacts in X-ray CT images. The second section is devoted to the evolution of CT technology from the first translation-rotation systems to multi-slice spiral CTs currently used today. The next section addresses specific developments of CT technology and applications, like perfusion CT, quantitative CT, and spectral CT. The fourth section introduces the problem of radiation exposure delivered to the patient and its evaluation. Finally the last section addresses the development in micro- and even nano-CT which is a rapidly evolving area in preclinical imaging and biology.

  19. Functional Brain Imaging

    Directory of Open Access Journals (Sweden)

    K. Vessal

    2005-08-01

    Full Text Available Introduction & Background: The historical evolution of concepts of the mind has had a tremendous impact on human civilization. Aside from Smith’s surgical papyrus, there exists practically no documentation down to the era of Hippocrates. While in Corpus, the seat of all sensations is put in the brain, there is an amazing regression, for many centuries thereafter notably influenced by Aristotle, to displace it to the heart. This erroneous diversion promulgated in De Anima with minor corrections by Galen, has per-petuated to our time when we say, for example, that we love something with our very hearts or “knowing by heart” when we mean to memorize something. Avicenna challenged many of Aristotle’s ideas in El-monnafs (psychology section of Al Shafa, paving the road for the later European Renaissance. Cartesian choice of pineal body as the seat of soul in the first half of the 7th century was a fundamental departure from brain-soul dichotomy. It was followed by Gall’s pseudo-science, phrenology, as the first attempt of brain mapping in ascribing “mental faculties” to the speculative “organs” of the brain. Brain mapping through Functional Brain Imaging has flourished ex-tensively in the past decades -starting from PET with later substitution by fMRI- as robust tools for interro-gating mysteries of the brain. With a surprising pace of development, Functional Brain Imaging heralds a welcome adjunct to the science of radiology in ex-ploring mind and human behavior. Given the multi-tude of appropriate MRI machines operating across the country, attention to this aspect of imaging can invigorate research in radiology and boost generation of knowledge in this rapidly growing field. Recent advances in MRI fast imaging, fMRI, as well as clini-cal and spectroscopic imaging with present clinical application and future trends are discussed.

  20. MR and CT characteristics in tuberous sclerosis of the brain

    International Nuclear Information System (INIS)

    In a retrospective study of 26 patients with tuberous sclerosis, 16 patients underwent both CT and MR imaging evaluations. In 25 (96%) of the 26 patients CT disclosed subependymal nodules; in 23 (88%) patients the nodules were calcified. Parenchymal hamartomas, seen in 23 (88%) of the 26 patients, were hypodense in comparison with surrounding brain tissue in 16 (62%) patients and calcified in 14 (54%). Contrast enhancemenet of a lesion, indicating giant cell astrocytoma, was seen in three (12%) of the 16 patients. MR imaging disclosed subependymal nodules of intermediate signal intensity in ten (63%) of 16 patients. The nodules were better seen in T1-weighted pulse sequences. Parenchymal hamartomas, seen in 15 (94%) of 16 patients, usually had long T1 and T2 relaxation characteristics. This pattern was reversed in the neonate. A forme fruste of tuberous sclerosis in one patient that was seen on CT was not seen with MR imaging, which suggests that CT is the procedure of choice for screening patients for genetic counseling

  1. Helical CT scanner - 3D imaging and CT fluoroscopy

    International Nuclear Information System (INIS)

    It has been over twenty years since the introduction of X-ray CT. In recent years, the topic of helical scanning has dominated the area of technical development. With helical scanning now being used routinely, the traditional concept of the X-ray CT as a device for obtaining axial images of the body in slices has given way to that of one for obtaining images in volumes. For instance, the ability of helical scanning to acquire sequential images in the direction of the body axis makes it ideal for creating three dimensional (3-D) images, and has in fact led to the use of 3-D images in clinical practice. In addition, with helical scanning, imaging of organs such as the liver or lung can be performed in several tens of seconds, as opposed to a few minutes that it used to take. This has resulted not only in reduced time for the patient to spend under constraint for imaging but also to changes in diagnostic methods. The question, 'Would it be possible to perform reconstruction while scanning and to see resulting images in real time ?' is another issue which has been taken up, and it has been answered by CT Fluoroscopy. It makes it possible to see CT images in real time during sequential scanning, and from this development, applications such as CT-guided biopsy and CT-navigated surgery has been investigated and have been realized. Other possibilities to create a whole new series of diagnostic methods and results. (author)

  2. Brain imaging in dementia.

    Science.gov (United States)

    Bonifacio, Guendalina; Zamboni, Giovanna

    2016-06-01

    The introduction of MRI and positron emission tomography (PET) brain imaging has contributed significantly to the understanding of different dementia syndromes. Over the past 20 years these imaging techniques have been increasingly used for clinical characterisation and differential diagnosis, and to provide insight into the effects on functional capacity of the brain, patterns of spatial distribution of different dementia syndromes and their natural history and evolution over time. Brain imaging is also increasingly used in clinical trials, as part of inclusion criteria and/or as a surrogate outcome measure. Here we review all the relatively specific findings that can be identified with different MRI and PET techniques in each of the most frequent dementing disorders. PMID:26933232

  3. Brain Image Motion Correction

    DEFF Research Database (Denmark)

    Jensen, Rasmus Ramsbøl; Benjaminsen, Claus; Larsen, Rasmus;

    2015-01-01

    The application of motion tracking is wide, including: industrial production lines, motion interaction in gaming, computer-aided surgery and motion correction in medical brain imaging. Several devices for motion tracking exist using a variety of different methodologies. In order to use such devices...... offset and tracking noise in medical brain imaging. The data are generated from a phantom mounted on a rotary stage and have been collected using a Siemens High Resolution Research Tomograph for positron emission tomography. During acquisition the phantom was tracked with our latest tracking prototype...

  4. CT evaluation of the brain abscess: Comparison of CT and pathologic findings of brain

    International Nuclear Information System (INIS)

    This study was undertaken to correlate the CT and histopathologic findings of abscess wall. The CT findings of 12 patients with pathologically proven brain abscess were retrospectively analyzed with particular attention to the thickness, smoothness and uniformity of enhancing abscess wall, and the results were correlated with histopathologic findings. Two patients with acute cerebritis showed an isodense ring on non-contrast CT(NCCT),but a true capsule formation could not be identified at pathologic examination. Six other patients with isodense ring on NCCT consisted of early to late cerebritis(3 cases), late cerebritis to early calsule(1 case), early capsule(1 case), and late capsule(1 case). These 6 cases showed ring enhancement on contrast enhanced CT(CECT) and true capsule formation pathologically. There was no isodense ring on NCCT in the remaining four patients. They consisted of early to late cerebeitis(2 cases), late cerebritis(1 case), and late cerebritis to early capsule formation(1 case). These also showed ring enhancement on CECT and true capsule formation pathologically. We found that it is different to predict the exact stage of brain abscess on preoperative CT findings. It is suggested that clinical findings and sequential dynamic CT may provide more detailed information for evaluation of abscess staging

  5. CT evaluation of the brain abscess: Comparison of CT and pathologic findings of brain

    Energy Technology Data Exchange (ETDEWEB)

    Moon, Jeoung Mi; Park, Ji Hyun; Kim, Ji Yang; Yim, Neung Jae; Song, Ik Hoon; Kim, Byung Heon [Massan Koryo General Hospital, Massan (Korea, Republic of)

    1994-09-15

    This study was undertaken to correlate the CT and histopathologic findings of abscess wall. The CT findings of 12 patients with pathologically proven brain abscess were retrospectively analyzed with particular attention to the thickness, smoothness and uniformity of enhancing abscess wall, and the results were correlated with histopathologic findings. Two patients with acute cerebritis showed an isodense ring on non-contrast CT(NCCT),but a true capsule formation could not be identified at pathologic examination. Six other patients with isodense ring on NCCT consisted of early to late cerebritis(3 cases), late cerebritis to early calsule(1 case), early capsule(1 case), and late capsule(1 case). These 6 cases showed ring enhancement on contrast enhanced CT(CECT) and true capsule formation pathologically. There was no isodense ring on NCCT in the remaining four patients. They consisted of early to late cerebeitis(2 cases), late cerebritis(1 case), and late cerebritis to early capsule formation(1 case). These also showed ring enhancement on CECT and true capsule formation pathologically. We found that it is different to predict the exact stage of brain abscess on preoperative CT findings. It is suggested that clinical findings and sequential dynamic CT may provide more detailed information for evaluation of abscess staging.

  6. Functional brain imaging

    International Nuclear Information System (INIS)

    Functional magnetic resonance imaging (fMRI) is a non-invasive method that has become one of the major tools for understanding human brain function and in recent years has also been developed for clinical applications. Changes in hemodynamic signals correspond to changes in neuronal activity with good spatial and temporal resolution in fMRI. Using high-field MR systems and increasingly dedicated statistics and postprocessing, activated brain areas can be detected and superimposed on anatomical images. Currently, fMRI data are often combined in multimodal imaging, e. g. with diffusion tensor imaging (DTI) sequences. This method is helping to further understand the physiology of cognitive brain processes and is also being used in a number of clinical applications. In addition to the blood oxygenation level-dependent (BOLD) signals, this article deals with the construction of fMRI investigations, selection of paradigms and evaluation in the clinical routine. Clinically, this method is mainly used in the planning of brain surgery, analyzing the location of brain tumors in relation to eloquent brain areas and the lateralization of language processing. As the BOLD signal is dependent on the strength of the magnetic field as well as other limitations, an overview of recent developments is given. Increases of magnetic field strength (7 T), available head coils and advances in MRI analytical methods have led to constant improvement in fMRI signals and experimental design. Especially the depiction of eloquent brain regions can be done easily and quickly and has become an essential part of presurgical planning. (orig.)

  7. Tumor hypoxia and microscopic diffusion capacity in brain tumors: A comparison of {sup 62}Cu-Diacetyl-Bis (N4-Methylthiosemicarbazone) PET/CT and diffusion-weighted MR imaging

    Energy Technology Data Exchange (ETDEWEB)

    Hino-Shishikura, Ayako; Tateishi, Ukihide; Shibata, Hirofumi; Yoneyama, Tomohiro; Nishii, Toshiaki; Torii, Ikuo; Inoue, Tomio [Graduate School of Medicine, Yokohama City University, Department of Radiology, Yokohama (Japan); Tateishi, Kensuke; Ohtake, Makoto; Kawahara, Nobutaka [Graduate School of Medicine, Yokohama City University, Department of Neurosurgery, Yokohama (Japan)

    2014-07-15

    The aim of this study was to clarify the relationship between tumor hypoxia and microscopic diffusion capacity in primary brain tumors using {sup 62}Cu-Diacetyl-Bis (N4-Methylthiosemicarbazone) ({sup 62}Cu-ATSM) PET/CT and diffusion-weighted MR imaging (DWI). This study was approved by the institutional human research committee and was HIPAA compliant, and informed consent was obtained from all patients. {sup 62}Cu-ATSM PET/CT and DWI were performed in a total of 40 primary brain tumors of 34 patients with low grade glioma (LGG, n = 13), glioblastoma (GBM, n = 20), and primary central nervous system lymphoma (PCNSL, n = 7). {sup 62}Cu-ATSM PET/CT parameters and apparent diffusion coefficient (ADC) obtained by DWI were compared. High intensity signals by {sup 62}Cu-ATSM PET/CT and DWI in patients with GBM and PCNSL, and low intensity signals in LGG patients were observed. An inverse correlation was found between maximum SUV (SUV{sub max}) and minimum ADC (ADC{sub min}) (r = -0.583, p < 0.0001), and between tumor/brain ratio (T/B{sub ratio}) and ADC{sub min} for all tumors (r = -0.532, p < 0.0001). Both SUV{sub max} and T/B{sub ratio} in GBM were higher than LGG (p < 0.0001 and p < 0.0001), and those in PCNSL were also higher than GBM (p = 0.033 and p = 0.044). The ADC{sub min} was lower in GBM (p = 0.011) and PCNSL (p = 0.01) than in LGG, while no significant difference was found between GBM and PCNSL (p = 0.90). Tumor hypoxia assessed by {sup 62}Cu-ATSM PET/CT correlated with microscopic diffusion capacity obtained by DWI in brain tumors. Both {sup 62}Cu-ATSM PET/CT and DWI were considered feasible imaging methods for grading glioma. However, {sup 62}Cu-ATSM PET/CT provided additional diagnostic information to differentiate between GBM and PCNSL. (orig.)

  8. Improvement of image quality and radiation dose of CT perfusion of the brain by means of low-tube voltage (70 KV)

    Energy Technology Data Exchange (ETDEWEB)

    Li, Zhen-lin; Zhang, Kai; Li, Wang-jiang; Chen, Xian; Wu, Bin; Song, Bin [West China Hospital of Sichuan University, Department of Radiology, Chengdu, Sichuan (China); Li, Hang [Sichuan Provincial People' s Hospital, Department of Radiology, Chengdu, Sichuan (China)

    2014-08-15

    To investigate the feasibility of 70 kV cerebral CT perfusion by comparing image quality and radiation exposure to 80 kV. Thirty patients with suspected cerebral ischemia who underwent dual-source CT perfusion were divided into group A (80 kV, 150 mAs) and group B (70 kV, 150 mAs). Quantitative comparisons were used for maximum enhancement, signal-to-noise index (SNI), and values of cerebral blood flow (CBF), cerebral blood flow (CBV), mean transit time (MTT) on CBF, CBV, and MTT images, and radiation dose from these two groups. Qualitative perfusion images were assessed by two readers. Maximum enhancement for group B was higher than group A (P < 0.05). There were no significant differences between the two groups for SNI on CBF and CBV maps (P = 0.06 - 0.576), but significant differences for MTT when SNI was measured on frontal white matter and temporo-occipital white matter (P < 0.05). There were no differences among values of CBF, CBV, and MTT for both groups (P = 0.251-0.917). Mean image quality score in group B was higher than group A for CBF (P < 0.05), but no differences for CBV (P = 0.542) and MTT (P = 0.962). Radiation dose for group B decreased compared with group A. 70 kV cerebral CT perfusion reduces radiation dose without compromising image quality. (orig.)

  9. Image-guided neurosurgery with intra-operative CT

    International Nuclear Information System (INIS)

    Intra-operative use of a mobile CT scanner permits to replace the reference images for the navigation system by the scans made during cerebral surgery, so that intra-operative anatomic changes such as brain shift can be taken into account. (orig./CB)

  10. Acute toxic encephalopathies: CT and MR imaging features

    International Nuclear Information System (INIS)

    An endless variety of toxins can cause degenerative brain lesions both by chronic use of small amounts and by acute exposures from industrial accidents or suicide attempts. The more commonly occurring toxins encountered clinically include carbon monoxide, cyanide, methanol, and ethylene glycol. CT and MR imaging are of great importance in the assessment of the comatose patient. Some of these toxins have a propensity for selective bilateral and symmetric involvement of the basal ganglia as well as the white matter. CT and MR can demonstrate the extent and distribution of the morphologic brain changes

  11. An introduction to PET/CT imaging

    International Nuclear Information System (INIS)

    Since its introduction in 1998, dual-modality PET/CT imaging has received great attention in the medical community. Patients are examined with both CT and PET in a whole-body single examination in the same scanner and fusion can be obtained directly obviating the need for software registration. The CT images are used for anatomic reference of the tracer uptake patterns imaged in PET, as well as for attenuation correction of the PET data. This review discusses the technical background of PET with F-18-fluorodeoxyglucose, CT and combined PET/CT devices. Clinical applications in oncology are considered. Fusion of the anatomic information provided by CT and the metabolic information provided by PET in PET/CT imaging allows a higher diagnostic accuracy for lesion localisation than PET plus CT performed independently. Image artefacts can result from CT-based attenuation methodology that can overcorrect dense objects generating hot spot artefacts in attenuation correction PET images and mismatches in CT and PET studies due to respiratory movements and the different patient positioning between both examinations. (author)

  12. Brain hypoxia imaging

    Energy Technology Data Exchange (ETDEWEB)

    Song, Ho Chun [Chonnam National University Medical School, Gwangju (Korea, Republic of)

    2007-04-15

    The measurement of pathologically low levels of tissue pO{sub 2} is an important diagnostic goal for determining the prognosis of many clinically important diseases including cardiovascular insufficiency, stroke and cancer. The target tissues nowadays have mostly been tumors or the myocardium, with less attention centered on the brain. Radiolabelled nitroimidazole or derivatives may be useful in identifying the hypoxic cells in cerebrovascular disease or traumatic brain injury, and hypoxic-ischemic encephalopathy. In acute stroke, the target of therapy is the severely hypoxic but salvageable tissue. {sup 18}F-MISO PET and {sup 99m}Tc-EC-metronidazole SPECT in patients with acute ischemic stroke identified hypoxic tissues and ischemic penumbra, and predicted its outcome. A study using {sup 123}I-IAZA in patient with closed head injury detected the hypoxic tissues after head injury. Up till now these radiopharmaceuticals have drawbacks due to its relatively low concentration with hypoxic tissues associated with/without low blood-brain barrier permeability and the necessity to wait a long time to achieve acceptable target to background ratios for imaging in acute ischemic stroke. It is needed to develop new hypoxic marker exhibiting more rapid localization in the hypoxic region in the brain. And then, the hypoxic brain imaging with imidazoles or non-imidazoles may be very useful in detecting the hypoxic tissues, determining therapeutic strategies and developing therapeutic drugs in several neurological disease, especially, in acute ischemic stroke.

  13. Electromagnetic brain imaging

    International Nuclear Information System (INIS)

    Present imaging methods of cerebral neuro-activity like brain functional MRI and positron emission tomography (PET) secondarily measure only average activities within a time of the second-order (low time-resolution). In contrast, the electromagnetic brain imaging (EMBI) directly measures the faint magnetic field (10-12-10-13 T) yielded by the cerebral activity with use of multiple arrayed sensors equipped on the head surface within a time of sub-millisecond order (high time-resolution). The sensor array technology to find the signal source from the measured data is common in wide areas like signal procession for radar, sonar, and epicenter detection by seismic wave. For estimating and reconstructing the active region in the brain in EMBI, the efficient method must be developed and this paper describes the direct and inverse problems concerned in signal and image processions of EMBI. The direct problem involves the cerebral magnetic field/lead field matrix and inverse problem for reconstruction of signal source, the MUSIC (multiple signal classification) algorithm, GLRT (generalized likelihood ratio test) scan, and adaptive beamformer. As an example, given are results of magnetic intensity changes (unit, fT) in the somatosensory cortex vs time (msec) measured by 160 sensors and of images reconstructed from EMBI and MRI during electric muscle afferent input from the hand. The real-time imaging is thus possible with EMBI and extremely, the EMBI image, the real-time cerebral signals, can inversely operate a machine, of which application directs toward the brain/machine interface development. (R.T.)

  14. Brain perfusion CT for acute stroke using a 256-slice CT: improvement of diagnostic information by large volume coverage

    Energy Technology Data Exchange (ETDEWEB)

    Dorn, F. [Technical University, Department of Radiology, Klinikum rechts der Isar, Munich (Germany); Institut fuer Radiologie, Klinikum rechts der Isar der Technischen Universitaet Muenchen, Muenchen (Germany); Muenzel, D.; Meier, R.; Rummeny, E.J.; Huber, A. [Technical University, Department of Radiology, Klinikum rechts der Isar, Munich (Germany); Poppert, H. [Technical University, Department of Neurology, Klinikum rechts der Isar, Munich (Germany)

    2011-09-15

    To compare a 256-slice CT with a simulated standard CT for brain CT perfusion (CTP). CTP was obtained in 51 patients using a 256-slice CT (128 detector rows, flying z-focus, 8-cm detector width, 80 kV, 120mAs, 20 measurements, 1 CT image/2.5 s). Signal-to-noise ratios (SNR) were compared in grey and white matter. Perfusion maps were evaluated for cerebral blood flow (CBF), cerebral blood volume (CBV) and mean transit time (MTT) in hypoperfused areas and corresponding contralateral regions. Two reconstructed 10-mm slices for simulation of a standard CT (SDCT) were compared with the complete data sets (large-volume CT, LVCT). Adequate image quality was achieved in 50/51 cases. SNR were significantly different in grey and white matter. A perfusion deficit was present in 27 data sets. Differences between the hypoperfusions and the control regions were significant for MTT and CBF, but not for CBV. Three lesions were missed by SDCT but detected by LVCT; 24 lesions were covered incompletely by SDCT, and 6 by LVCT. 21 lesions were detected completely by LVCT, but none by SDCT. CTP imaging of the brain using an increased detector width can detect additional ischaemic lesions and cover most ischaemic lesions completely. (orig.)

  15. MR imaging of acute hemorrhagic brain infarction

    International Nuclear Information System (INIS)

    Six patients with acute hemorrhagic brain infarct were imaged using spin-echo (SE) pulse sequences on a 1.5 Tesla MR scanner. Including two patients with repeated MR imaging, a total of eight examinations, all performed within 15 days after stroke, were analyzed retrospectively. Four patients revealed massive hemorrhages in the basal ganglia or cerebellum and three cases demonstrated multiple linear hemorrhages in the cerebral cortex. On T1-weighted images, hemorrhages were either mildly or definitely hyperintense relative to gray matter, while varied from mildly hypointense to hyperintense on T2-weighted images. T1-weighted images were superior to T2-weighted images in detection of hemorrhgage. CT failed to detect hemorrhage in two of five cases: indicative of MR superiority to CT in the diagnosis of acute hemorrhagic infarcts. (author)

  16. MR imaging of acute hemorrhagic brain infarction

    Energy Technology Data Exchange (ETDEWEB)

    Uchino, Akira; Ohnari, Norihiro; Ohno, Masato (Kyushu Rosai Hospital, Fukuoka (Japan))

    1989-11-01

    Six patients with acute hemorrhagic brain infarct were imaged using spin-echo (SE) pulse sequences on a 1.5 Tesla MR scanner. Including two patients with repeated MR imaging, a total of eight examinations, all performed within 15 days after stroke, were analyzed retrospectively. Four patients revealed massive hemorrhages in the basal ganglia or cerebellum and three cases demonstrated multiple linear hemorrhages in the cerebral cortex. On T1-weighted images, hemorrhages were either mildly or definitely hyperintense relative to gray matter, while varied from mildly hypointense to hyperintense on T2-weighted images. T1-weighted images were superior to T2-weighted images in detection of hemorrhgage. CT failed to detect hemorrhage in two of five cases: indicative of MR superiority to CT in the diagnosis of acute hemorrhagic infarcts. (author).

  17. Functional brain imaging - baric and clinical questions

    International Nuclear Information System (INIS)

    The advancing biological knowledge of disease processes plays a central part in the progress of modern psychiatry. An essential contribution comes from the functional and structural brain imaging techniques (CT, MRI, SPECT, PET). Their application is important for biological oriented research in psychiatry and there is also a growing relevance in clinical aspects. This development is taken into account by recent diagnostic classification systems in psychiatry. The capabilities and limitations of functional brain imaging in the context of research and clinic will be presented and discussed by examples and own investigations. (orig.)

  18. Brain imaging and autism

    Energy Technology Data Exchange (ETDEWEB)

    Zilbovicius, M. [Service Hospitalier Frederic Joliot (CEA/DSV/DRM), INSERM CEA 0205, 91 - Orsay (France)

    2006-07-01

    Autism is a neuro-developmental disorder with a range of clinical presentations, from mild to severe, referred to as autism spectrum disorders (ASD). The most common clinical ASD sign is social interaction impairment, which is associated with verbal and non-verbal communication deficits and stereotyped and obsessive behaviors. Thanks to recent brain imaging studies, scientists are getting a better idea of the neural circuits involved in ASD. Indeed, functional brain imaging, such as positron emission tomography (PET), single positron emission tomograph y (SPECT) and functional MRI (fMRI) have opened a new perspective to study normal and pathological brain functions. Three independent studies have found anatomical and rest functional temporal abnormalities. These anomalies are localized in the superior temporal sulcus bilaterally which are critical for perception of key social stimuli. In addition, functional studies have shown hypo-activation of most areas implicated in social perception (face and voice perception) and social cognition (theory of mind). These data suggest an abnormal functioning of the social brain network. The understanding of such crucial abnormal mechanism may drive the elaboration of new and more adequate social re-educative strategies in autism. (author)

  19. Brain imaging and autism

    International Nuclear Information System (INIS)

    Autism is a neuro-developmental disorder with a range of clinical presentations, from mild to severe, referred to as autism spectrum disorders (ASD). The most common clinical ASD sign is social interaction impairment, which is associated with verbal and non-verbal communication deficits and stereotyped and obsessive behaviors. Thanks to recent brain imaging studies, scientists are getting a better idea of the neural circuits involved in ASD. Indeed, functional brain imaging, such as positron emission tomography (PET), single positron emission tomograph y (SPECT) and functional MRI (fMRI) have opened a new perspective to study normal and pathological brain functions. Three independent studies have found anatomical and rest functional temporal abnormalities. These anomalies are localized in the superior temporal sulcus bilaterally which are critical for perception of key social stimuli. In addition, functional studies have shown hypo-activation of most areas implicated in social perception (face and voice perception) and social cognition (theory of mind). These data suggest an abnormal functioning of the social brain network. The understanding of such crucial abnormal mechanism may drive the elaboration of new and more adequate social re-educative strategies in autism. (author)

  20. CT findings in brain edema following the administration of corticosteroids

    International Nuclear Information System (INIS)

    Computed tomography (CT) is the first noninvasive method available for directly visualizing brain edema in man. On CT scans perifocal edema is shown as an area of low density surrounding a lesion. The purpose of this report is to evaluate the effect of corticosteroids on brain edema as seen by CT (HITACHI CT-H 250). Nine patients with brain-tumor and one with brain-abscess were treated with betamethasone for about ten days (dosage started with 12 - 16 mg/day, and tapered). In eight cases, and improvement in the neurological findings was observed. An impressive reduction of peritumoral edema was shown on CT scans in six of these eight cases. There was, however, no significant correlation between the degree of the reduction of edema on CT and that of the improvement in neurological findings. The mode of the CT number in the region of edema did not differ significantly between pre- and post-steroid treatment in the cases showing a recognizable reduction of edema on CT. This failure to change is probably due to the insufficient mechanical accuracy of the CT scanner at the present stage of technology. Through our experiences, it seems that CT is one of the most promising tools for a dynamic study of brain edema in man. (author)

  1. Blind Analysis of CT Image Noise Using Residual Denoised Images

    OpenAIRE

    Roychowdhury, Sohini; Hollraft, Nathan; Alessio, Adam

    2016-01-01

    CT protocol design and quality control would benefit from automated tools to estimate the quality of generated CT images. These tools could be used to identify erroneous CT acquisitions or refine protocols to achieve certain signal to noise characteristics. This paper investigates blind estimation methods to determine global signal strength and noise levels in chest CT images. Methods: We propose novel performance metrics corresponding to the accuracy of noise and signal estimation. We implem...

  2. Significance of CT in urological imaging diagnosis

    International Nuclear Information System (INIS)

    There have been many reports about the usefulness of the CT imaging on the urological fields. Advance in CT equipment provides us some new diagnostic and therapeutic yields. There are the reconstruction, the dynamic scanning and the therapeutic application. Therefore, in addition to the ordinary characteristics of conventional CT equipment, the new CT scanner has several clinical advantages of the sagittal and coronal reformation, of the dynamic and quantitative evaluation, and of applying to radiation therapy planning. The CT scan should be performed reasonably after consideration of the potential advantages. (author)

  3. Imaging brain plasticity after trauma

    OpenAIRE

    Kou, Zhifeng; Iraji, Armin

    2014-01-01

    The brain is highly plastic after stroke or epilepsy; however, there is a paucity of brain plasticity investigation after traumatic brain injury (TBI). This mini review summarizes the most recent evidence of brain plasticity in human TBI patients from the perspective of advanced magnetic resonance imaging. Similar to other forms of acquired brain injury, TBI patients also demonstrated both structural reorganization as well as functional compensation by the recruitment of other brain regions. ...

  4. Panoramic three-dimensional CT imaging

    International Nuclear Information System (INIS)

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

  5. Panoramic three-dimensional CT imaging

    Energy Technology Data Exchange (ETDEWEB)

    Kawamata, Akitoshi; Fujishita, Masami [Asahi Univ., Hozumi, Gifu (Japan). School of Dentistry

    1998-09-01

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

  6. Image Registration for PET/CT and CT Images with Particle Swarm Optimization

    International Nuclear Information System (INIS)

    Image registration is a fundamental task in image processing used to match two or more images. It gives new information to the radiologists by matching images from different modalities. The objective of this study is to develop 2D image registration algorithm for PET/CT and CT images acquired by different systems at different times. We matched two CT images first (one from standalone CT and the other from PET/CT) that contain affluent anatomical information. Then, we geometrically transformed PET image according to the results of transformation parameters calculated by the previous step. We have used Affine transform to match the target and reference images. For the similarity measure, mutual information was explored. Use of particle swarm algorithm optimized the performance by finding the best matched parameter set within a reasonable amount of time. The results show good agreements of the images between PET/CT and CT. We expect the proposed algorithm can be used not only for PET/CT and CT image registration but also for different multi-modality imaging systems such as SPECT/CT, MRI/PET and so on.

  7. Brain abscess in a Japanese Black calf: Utility of computed tomography (CT)

    International Nuclear Information System (INIS)

    Computed tomography (CT) was used for diagnosis of brain abscess in a 6-month-old, Japanese Black calf presented with neurological dysfunction, compulsive circling and vision disturbance. CT images showed asymmetric lateral ventricles, and presence of intra-cranial multiple low absorption lesions surrounded by capsule suggestive of abscess in the right cerebral hemisphere. Postmortem examination revealed marked swelling of right cerebral hemisphere and olfactory bulb. Multilocular large abscess containing creamy pus was found to occupy most area of periventricular and lateral ventricle. Fusobacterium necrophrum was isolated from the abscess contents as the causative agent. These results demonstrate that CT is useful tool for tentative diagnosis of bovine brain abscess

  8. Paediatric CT imaging trends in Australia

    International Nuclear Information System (INIS)

    Full text: The use of CT has rapidly increased since its introduction. Although an important medical tool for diagnosis and treatment, CT is rec ognised as being among the highest contributors to population radiation exposure. As the risks associated with exposure are higher for children than for adults, this study assessed the impact of paediatric CT in Australia by analysing imaging trends. CT imaging trends were derived from Medicare data. Comparable data from a dedicated paediatric hospital (Royal Children's Hospital Melbourne (RCH)) were analysed to determine the validity of utilising Medicare statistics in the younger age groups. The resulting trends reflect the situation for paediatric CT imaging in Australia. In 2009, 2.1 million CT services were billed to Medicare in Australia for children and adults. The average annual growth in the number of CT services provided since 1994 was 8.5%, compared with population growth of 1.4%. Comparison of RCH and Medicare data revealed that only one third of pae diatric CT imaging is captured by Medicare. Combining the data sets showed that over the last 20 years, there has been an average annual increase of 5.1% in the CT imaging rate for 0 to 18-year-olds. However, in recent years, growth in the imaging rate for 11 to 18-year-olds has slowed, while for 5 to 10-year-olds the imaging rate has declined. The significant growth in CT services is attributable to increased demand from the adult demographic. Conversely, increases in the imaging rate for paediatric patients have slowed overall. In fact, for some age groups the rate has fallen.

  9. SPECT/CT workflow and imaging protocols

    International Nuclear Information System (INIS)

    Introducing a hybrid imaging method such as single photon emission computed tomography (SPECT)/CT greatly alters the routine in the nuclear medicine department. It requires designing new workflow processes and the revision of original scheduling process and imaging protocols. In addition, the imaging protocol should be adapted for each individual patient, so that performing CT is fully justified and the CT procedure is fully tailored to address the clinical issue. Such refinements often occur before the procedure is started but may be required at some intermediate stage of the procedure. Furthermore, SPECT/CT leads in many instances to a new partnership with the radiology department. This article presents practical advice and highlights the key clinical elements which need to be considered to help understand the workflow process of SPECT/CT and optimise imaging protocols. The workflow process using SPECT/CT is complex in particular because of its bimodal character, the large spectrum of stakeholders, the multiplicity of their activities at various time points and the need for real-time decision-making. With help from analytical tools developed for quality assessment, the workflow process using SPECT/CT may be separated into related, but independent steps, each with its specific human and material resources to use as inputs or outputs. This helps identify factors that could contribute to failure in routine clinical practice. At each step of the process, practical aspects to optimise imaging procedure and protocols are developed. A decision-making algorithm for justifying each CT indication as well as the appropriateness of each CT protocol is the cornerstone of routine clinical practice using SPECT/CT. In conclusion, implementing hybrid SPECT/CT imaging requires new ways of working. It is highly rewarding from a clinical perspective, but it also proves to be a daily challenge in terms of management. (orig.)

  10. Fracture Detection in Traumatic Pelvic CT Images

    OpenAIRE

    Jie Wu; Pavani Davuluri; Kevin R. Ward; Charles Cockrell; Rosalyn Hobson; Kayvan Najarian

    2012-01-01

    Fracture detection in pelvic bones is vital for patient diagnostic decisions and treatment planning in traumatic pelvic injuries. Manual detection of bone fracture from computed tomography (CT) images is very challenging due to low resolution of the images and the complex pelvic structures. Automated fracture detection from segmented bones can significantly help physicians analyze pelvic CT images and detect the severity of injuries in a very short period. This paper presents an automated hie...

  11. MR and CT imaging of cerebral fat embolism

    International Nuclear Information System (INIS)

    Objective: To summarize the clinical characteristics and imaging features of cerebral fat embolism (CFE). Methods: The clinical features and imaging appearances of 3 cases with acute CFE were analyzed. Results: (1) 3 non-head injured cases had sudden mental status changes after leg injury. (2) The main clinical manifestation was vigil coma. (3) MRI showed lesions of the brain in all 3 cases. Cranial CT showed lesions in only 1 case. (4) MRI and CT showed spotty and patchy symmetrical lesions, which were low signal on T1WI and high signal on T2WI, and low density on CT scan. The lesions were distributed in the white matter along the boundary zones of the major vascular territories, thalamus and basal ganglia, internal capsule, corpus callosum, brain stem, and cerebellum. The margins of the lesions were obscure. (5) 1 case received MRI examination after therapy for 3 months, which showed no lesions in the brain. Conclusion: Cerebral fat embolism has its own clinical features and imaging characteristics. MRI is superior to CT in diagnosing CFE

  12. PET-CT imaging in pediatric oncology

    OpenAIRE

    McCarville, M. Beth

    2009-01-01

    Abstract Positron emission tomography (PET)-computed tomography (CT) is emerging as a valuable tool for assessing a wide variety of pediatric malignancies, including lymphomas, soft-tissue tumors, and bone sarcomas. PET-CT may provide information that is not apparent on conventional imaging performed to stage these diseases and monitor their response to treatment. The use of PET-CT in children requires an awareness of the technical and logistical issues unique to this patient population. In a...

  13. MR imaging of the neonatal brain: Pathologic features

    International Nuclear Information System (INIS)

    Seventy-three neonates, aged 29-43 weeks since conception, were studied. US and/or CT correlations were obtained in most infants with pathology. In the first 4-5 days after hemorrhage, US and CT were superior to MR imaging, but after that time MR imaging was the single best modality for imaging blood. In early premature infants with very watery white matter, US detected infarction and brain edema that were poorly seen on both MR imaging and CT. However, in late premature and full-term infants, MR imaging was better than CT in distinguishing between normal white matter and infarction. Only MR imaging disclosed delayed myelination in 13 term infants with hydrocephalus and severe asphyxia. MR imaging with play an important role in imaging neonates once MR imaging-compatible monitors and neonatal head coils become widely available

  14. Imaging of brain TSPO expression in a mouse model of amyotrophic lateral sclerosis with {sup 18}F-DPA-714 and micro-PET/CT

    Energy Technology Data Exchange (ETDEWEB)

    Gargiulo, S.; Gramanzini, M. [National Research Council, Institute of Biostructure and Bioimaging, Naples (Italy); Ceinge Biotecnologie Avanzate s.c. a r.l., Naples (Italy); Anzilotti, S.; Salvatore, M. [IRCCS SDN, Naples (Italy); Coda, A.R.D.; Panico, M.; Zannetti, A.; Vicidomini, C.; Quarantelli, M.; Pappata, S. [National Research Council, Institute of Biostructure and Bioimaging, Naples (Italy); Greco, A.; Brunetti, A. [University ' ' Federico II' ' , Department of Advanced Biomedical Sciences, Naples (Italy); Ceinge Biotecnologie Avanzate s.c. a r.l., Naples (Italy); Vinciguerra, A.; Pignataro, G. [University ' ' Federico II' ' , Division of Pharmacology, Department of Neuroscience, Reproductive and Dentistry Sciences, School of Medicine, Naples (Italy); Dolle, F. [CEA, Institute for Biomedical Imaging, Orsay (France); Annunziato, L. [University ' ' Federico II' ' , Division of Pharmacology, Department of Neuroscience, Reproductive and Dentistry Sciences, School of Medicine, Naples (Italy); IRCCS SDN, Naples (Italy)

    2016-07-15

    To evaluate the feasibility and sensitivity of {sup 18}F-DPA-714 for the study of microglial activation in the brain and spinal cord of transgenic SOD1{sup G93A} mice using high-resolution PET/CT and to evaluate the Iba1 and TSPO expression with immunohistochemistry. Nine symptomatic SOD1{sup G93A} mice (aged 117 ± 12.7 days, clinical score range 1 - 4) and five WT SOD1 control mice (aged 108 ± 28.5 days) underwent {sup 18}F-DPA-714 PET/CT. SUV ratios were calculated by normalizing the cerebellar (rCRB), brainstem (rBS), motor cortex (rMCX) and cervical spinal cord (rCSC) activities to that of the frontal association cortex. Two WT SOD1 and six symptomatic SOD1{sup G93A} mice were studied by immunohistochemistry. In the symptomatic SOD1{sup G93A} mice, rCRB, rBS and rCSC were increased as compared to the values in WT SOD1 mice, with a statistically significantly difference in rBS (2.340 ± 0.784 vs 1.576 ± 0.287, p = 0.014). Immunofluorescence studies showed that TSPO expression was increased in the trigeminal, facial, ambiguus and hypoglossal nuclei, as well as in the spinal cord, of symptomatic SOD1{sup G93A} mice and was colocalized with increased Iba1 staining. Increased {sup 18}F-DPA-714 uptake can be detected with high-resolution PET/CT in the brainstem of transgenic SOD1{sup G93A} mice, a region known to be a site of degeneration and increased microglial activation in amyotrophic lateral sclerosis, in agreement with increased TSPO expression in the brainstem nuclei shown by immunostaining. Therefore, {sup 18}F-DPA-714 PET/CT might be a suitable tool to evaluate microglial activation in the SOD1{sup G93A} mouse model. (orig.)

  15. Quantitative Techniques in PET-CT Imaging

    NARCIS (Netherlands)

    Basu, Sandip; Zaidi, Habib; Holm, Soren; Alavi, Abass

    2011-01-01

    The appearance of hybrid PET/CT scanners has made quantitative whole body scanning of radioactive tracers feasible. This paper deals with the novel concepts for assessing global organ function and disease activity based on combined functional (PET) and structural (CT or MR) imaging techniques, their

  16. Comparison of stroke infarction between CT perfusion and diffusion weighted imaging: preliminary results

    Science.gov (United States)

    Abd. Rahni, Ashrani Aizzuddin; Arka, Israna Hossain; Chellappan, Kalaivani; Mukari, Shahizon Azura; Law, Zhe Kang; Sahathevan, Ramesh

    2016-03-01

    In this paper we present preliminary results of comparison of automatic segmentations of the infarct core, between that obtained from CT perfusion (based on time to peak parameter) and diffusion weighted imaging (DWI). For each patient, the two imaging volumes were automatically co-registered to a common frame of reference based on an acquired CT angiography image. The accuracy of image registration is measured by the overlap of the segmented brain from both images (CT perfusion and DWI), measured within their common field of view. Due to the limitations of the study, DWI was acquired as a follow up scan up to a week after initial CT based imaging. However, we found significant overlap of the segmented brain (Jaccard indices of approximately 0.8) and the percentage of infarcted brain tissue from the two modalities were still fairly highly correlated (correlation coefficient of approximately 0.9). The results are promising with more data needed in future for clinical inference.

  17. Generalised brain edema and brain infarct in ergotamine abuse: Visualization by CT, MR and angiography

    International Nuclear Information System (INIS)

    Abuse of ergotamine can release a generalised brain edema and brain infarctions. This can be visualized by CT, MR and angiography. The reason, however, can only be found in the patients history. (orig.)

  18. The stylohyoid chain: CT imaging

    Energy Technology Data Exchange (ETDEWEB)

    Uysal Ramadan, Selma, E-mail: uysalselma@yahoo.co [Department of Radiology, Ankara Training and Research Hospital, Ankara 06590 (Turkey); Goekharman, Dilek, E-mail: gokharman@ttnet.net.t [Department of Radiology, Ankara Training and Research Hospital, Ankara 06590 (Turkey); Kosar, Pinar, E-mail: pkosar@hotmail.co [Department of Radiology, Ankara Training and Research Hospital, Ankara 06590 (Turkey); Kacar, Mahmut, E-mail: mkacar1961@gamil.co [Department of Radiology, Ankara Training and Research Hospital, Ankara 06590 (Turkey); Kosar, Ugur, E-mail: ugurkosar@hotmail.co [Department of Radiology, Ankara Training and Research Hospital, Ankara 06590 (Turkey)

    2010-09-15

    We aimed in this report to discuss the embryology, anatomy, theories of ossification and symptoms, clinical presentation, and diagnosis of the stylohyoid chain (SHC) variations, together with the role of radiographs, computed tomography (CT) and three-dimensional (3D)-CT in showing these variations. Because CT/3D-CT additionally facilitates visualization of the entire SHC with different axes, it is the most valuable method for establishing the relationship between the SHC and the surrounding tissue. SHC variation can be discovered during CT performed for indications other than ossified SHC. It is important to diagnose whether or not the SHC is ossified, since one of the treatment procedures in ossified SHC is total excision. If the clinician and radiologist are aware of these variations observed in the SHC, patients with vague symptoms may be spared unnecessary investigations and may be properly diagnosed earlier.

  19. Acute stroke: the role of CT perfusion imaging

    International Nuclear Information System (INIS)

    Full text: The development of thrombolytic and neuroprotective agents for the treatment of acute stroke has created an imperative for improved imaging techniques in the evaluation of acute stroke. This report illustrates the value of perfusion CT in the assessment of suspected acute stroke. Five cases are presented. To obtain the perfusion data, a rapid series of images was acquired without table movement following a bolus of contrast medium. Cerebral blood flow (CBF), cerebral blood volume (CBV) and mean transit time (MTT) were determined by mathematically modelling the temporal changes in contrast enhancement in the brain and vascular system. Pixel by pixel analysis allowed generation of perfusion maps. Infarction is associated with reduced CBF and CBV whereas preserved CBV in the presence of reduced CBF implies intact autoregulation and hence potentially salvageable tissue (ie penumbra). The size of the perfusion defect indicates prognosis. In two cases, CT perfusion imaging usefully excluded acute stroke, including one patient in whom a low density area on conventional CT was subsequently proven to be tumour. Cerebral ischaemia was confirmed in three cases, one with an old and a new infarction, one with a large conventional CT abnormality but only a small perfusion defect, and one demonstrating infarct and penumbra. Perfusion CT offers the ability to positively identify patients with nonhaemorrhage stroke in the presence of a normal conventional CT, to select those patients for whom thrombolysis is appropriate, and to provide an indication as to prognosis. Copyright (2002) Blackwell Science Pty Ltd

  20. Mass preserving image registration for lung CT

    DEFF Research Database (Denmark)

    Gorbunova, Vladlena; Sporring, Jon; Lo, Pechin;

    2012-01-01

    This paper presents a mass preserving image registration algorithm for lung CT images. To account for the local change in lung tissue intensity during the breathing cycle, a tissue appearance model based on the principle of preservation of total lung mass is proposed. This model is incorporated...... into a standard image registration framework with a composition of a global affine and several free-form B-Spline transformations with increasing grid resolution. The proposed mass preserving registration method is compared to registration using the sum of squared intensity differences as a similarity...... function on four groups of data: 44 pairs of longitudinal inspiratory chest CT scans with small difference in lung volume; 44 pairs of longitudinal inspiratory chest CT scans with large difference in lung volume; 16 pairs of expiratory and inspiratory CT scans; and 5 pairs of images extracted at end exhale...

  1. Blind Analysis of CT Image Noise Using Residual Denoised Images

    CERN Document Server

    Roychowdhury, Sohini; Alessio, Adam

    2016-01-01

    CT protocol design and quality control would benefit from automated tools to estimate the quality of generated CT images. These tools could be used to identify erroneous CT acquisitions or refine protocols to achieve certain signal to noise characteristics. This paper investigates blind estimation methods to determine global signal strength and noise levels in chest CT images. Methods: We propose novel performance metrics corresponding to the accuracy of noise and signal estimation. We implement and evaluate the noise estimation performance of six spatial- and frequency- based methods, derived from conventional image filtering algorithms. Algorithms were tested on patient data sets from whole-body repeat CT acquisitions performed with a higher and lower dose technique over the same scan region. Results: The proposed performance metrics can evaluate the relative tradeoff of filter parameters and noise estimation performance. The proposed automated methods tend to underestimate CT image noise at low-flux levels...

  2. Brain damage in hanging: a new CT finding

    International Nuclear Information System (INIS)

    We report a 23-year-old man who attempted suicide by hanging. There have been few reports of involvement of the brain parenchyma shown on CT, all showing ischaemic lesions. This is the first report of multifocal intracerebral haematomas due to hanging seen on CT. (orig.) (orig.)

  3. Imaging assessment of traumatic brain injury.

    Science.gov (United States)

    Currie, Stuart; Saleem, Nayyar; Straiton, John A; Macmullen-Price, Jeremy; Warren, Daniel J; Craven, Ian J

    2016-01-01

    Traumatic brain injury (TBI) constitutes injury that occurs to the brain as a result of trauma. It should be appreciated as a heterogeneous, dynamic pathophysiological process that starts from the moment of impact and continues over time with sequelae potentially seen many years after the initial event. Primary traumatic brain lesions that may occur at the moment of impact include contusions, haematomas, parenchymal fractures and diffuse axonal injury. The presence of extra-axial intracranial lesions such as epidural and subdural haematomas and subarachnoid haemorrhage must be anticipated as they may contribute greatly to secondary brain insult by provoking brain herniation syndromes, cranial nerve deficits, oedema and ischaemia and infarction. Imaging is fundamental to the management of patients with TBI. CT remains the imaging modality of choice for initial assessment due to its ease of access, rapid acquisition and for its sensitivity for detection of acute haemorrhagic lesions for surgical intervention. MRI is typically reserved for the detection of lesions that may explain clinical symptoms that remain unresolved despite initial CT. This is especially apparent in the setting of diffuse axonal injury, which is poorly discerned on CT. Use of particular MRI sequences may increase the sensitivity of detecting such lesions: diffusion-weighted imaging defining acute infarction, susceptibility-weighted imaging affording exquisite data on microhaemorrhage. Additional advanced MRI techniques such as diffusion tensor imaging and functional MRI may provide important information regarding coexistent structural and functional brain damage. Gaining robust prognostic information for patients following TBI remains a challenge. Advanced MRI sequences are showing potential for biomarkers of disease, but this largely remains at the research level. Various global collaborative research groups have been established in an effort to combine imaging data with clinical and

  4. Brain tumor (image)

    Science.gov (United States)

    Brain tumors are classified depending on the exact site of the tumor, the type of tissue involved, benign ... tendencies of the tumor, and other factors. Primary brain tumors can arise from the brain cells, the meninges ( ...

  5. The Experimental Research on the Frameless Registration of DSA/CT Images

    Institute of Scientific and Technical Information of China (English)

    HUANG Yong-feng; LI Wen; ZENG Pei-feng; ZHAO Jun

    2006-01-01

    DSA images show vessels with clarity and CT images show bones distinctly. In this paper, we present an experimental research on the frameless registration of DSA/CT images based on localization algorithm. With four external markers, the vessels and bones in human brain can be integrated. The mean accuracy of simulated experiment is about 2.0 mm. The experiment proved that the 3D images composed cerebral anatomy and vasculature could help neurosurgeons perform accurate diagnosis and make right operation planning.

  6. Gd-DTPA-enhanced MR imaging for metastatic brain tumors

    International Nuclear Information System (INIS)

    The present series consists of 24 patients with brain metastasis smaller than 10 mm in diameter demonstrated on Gd-DTPA enhanced MR imaging (Gd-MRI). All patients underwent contrast-enhanced (CE) CT to be compared with Gd-MRI in size, number and detectability. The primary lesions of the series included 18 patients with lung cancer (9 with adenocarcinoma, 4 with small cell cancer, 3 with squamous cell cancer and 2 with large cell cancer), 4 with breast cancer, and each 1 with parotid cancer and renal cell carcinoma. All 24 patients except one who underwent surgery were treated with radiation therapy. In 13 patients examined by Gd-MRI and CE-CT both before and after the brain irradiation, therapeutic effect was estimated on each diagnostic imaging comparatively. In regard to size of brain metastases of 24 patients, 91 lesions smaller than 5 mm in diameter were detected by Gd-MRI but only 15 by CE-CT. Three of all patients, no brain metastasis was found on CE-CT. In 6 patients estimated as CR (complete remission) by CE-CT after brain irradiation, Gd-MRI evidenced tumor residues in 5 patients to alter the score of therapeutic effect as PR (partial remission). The difference in therapeutic effects confirmed by Gd-MRI was noted according to histological results and size of metastasis. The most radiosensitive tumor was small cell lung cancer, of which brain metastases smaller than 5 mm in diameter completely disappeared after 20∼50 Gy irradiation. Prophylactic whole brain irradiation has been an alternative indication for small cell lung cancer when CT showed no evidence of brain metastasis. However, our data strongly suggest that the small or tiny brain metastases negative on CE-CT will become new subjects of 'radical' radiotherapy. The higher sensitivity of Gd-MRI for detecting brain metastasis may propose new clinical prospects in staging, planning of therapy and estimation of therapeutic effect. (author)

  7. Male patients dosimetry undergoing brain PET/CT exam for diagnosis of mild cognitive impairment

    International Nuclear Information System (INIS)

    Diagnosis of Mild Cognitive Impairment (MCI) can indicate an initial dementia framework, or increase in the likelihood of developing this. The PET/CT (positron emission tomography associated with computed tomography) has shown excellent prospects for MCI diagnosis. The PET/CT helps diagnosis, but the patients effective dose is higher, it depends on the computed tomography (CT) protocol and the radiopharmaceutical patient injected activity. This study evaluates the dose in 38 male patients undergoing this technique for MCI diagnosis. To assess the radiation level from CT modality imaging was used TLD100 detectors embedded in a male anthropomorphic Alderson Randon® phantom, undergoing the same imaging protocol to which patients were referred. The dose resulting of radiopharmaceutical injected activity was estimated using the ICRP106 model proposed. The PET / CT effective dose for producing image was (5.12 ± 0.90) mSv. The contribution to the effective dose due to the FDG brain incorporation was (0.12 ± 0.01) mSv and thyroid (0.13 ± 0.02) mSv. The effective dose contribution due to brain and thyroid CT irradiation was (0.18 ± 0.01) mSv and (0.010 ± 0.001) mSv, respectively. The use of optimized CT protocols and FDG injected activity reduction can assist in this procedure dose reduction. (author)

  8. Nasal polyps with metaplastic ossification: CT and MR imaging findings

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Yi Kyung; Kim, Hyung-Jin; Kim, Eunhee; Kim, Sung Tae [Sungkyunkwan University School of Medicine, Department of Radiology, Samsung Medical Center, Seoul (Korea, Republic of); Kim, Jinna [Yonsei University College of Medicine, Department of Radiology, Seoul (Korea, Republic of); Chung, Seung-Kyu [Sungkyunkwan University School of Medicine, Department of Otorhinolaryngology-Head and Neck Surgery, Samsung Medical Center, Seoul (Korea, Republic of); Ko, Young-Hyeh [Sungkyunkwan University School of Medicine, Department of Pathology, Samsung Medical Center, Seoul (Korea, Republic of)

    2010-12-15

    Metaplastic ossification is a rare event in nasal polyps. The purpose of this study was to review the computed tomography (CT) and magnetic resonance (MR) imaging findings of nasal polyps with metaplastic ossification. CT (n = 5) and MR (n = 3) images of five patients (four men and one woman; mean age, 59 years) with surgically proven nasal polyp with metaplastic ossification were retrospectively reviewed. The location and morphologic characteristics of metaplastic ossification were documented as well. All lesions were seen as lobulated (n = 3), ovoid (n = 1), or dumbbell-shaped (n = 1) benign-looking masses with a mean size of 3.7 cm (range, 2.4-6.5 cm), located unilaterally in the posterior nasal cavity and nasopharynx (n = 2), posterior nasoethmoidal tract (n = 2), and maxillary sinus and nasal cavity (n = 1). Compared with the brain stem, the soft tissue components of all lesions demonstrated isoattenuation on precontrast CT scans, slight hypointensity on T1-weighted MR images, and hyperintensity on T2-weighted MR images. On contrast-enhanced MR images, heterogeneous enhancement with marked peripheral enhancement was seen in two and homogeneous moderate enhancement in one. All lesions contained centrally located radiodense materials on CT scans, the shape of which was multiple clustered in three, single nodular in one, and single large lobulated in one. Although rare, metaplastic ossification can occur within nasal polyps. The possibility of its diagnosis may be raised when one sees a benign-looking sinonasal mass with centrally located radiodense materials on CT scans. MR imaging may be useful when mycetoma or inverted papilloma cannot be ruled out on CT scans. (orig.)

  9. Imaging brain plasticity after trauma

    Science.gov (United States)

    Kou, Zhifeng; Iraji, Armin

    2014-01-01

    The brain is highly plastic after stroke or epilepsy; however, there is a paucity of brain plasticity investigation after traumatic brain injury (TBI). This mini review summarizes the most recent evidence of brain plasticity in human TBI patients from the perspective of advanced magnetic resonance imaging. Similar to other forms of acquired brain injury, TBI patients also demonstrated both structural reorganization as well as functional compensation by the recruitment of other brain regions. However, the large scale brain network alterations after TBI are still unknown, and the field is still short of proper means on how to guide the choice of TBI rehabilitation or treatment plan to promote brain plasticity. The authors also point out the new direction of brain plasticity investigation. PMID:25206874

  10. Imaging brain plasticity after trauma

    Institute of Scientific and Technical Information of China (English)

    Zhifeng Kou; Armin Iraji

    2014-01-01

    The brain is highly plastic after stroke or epilepsy;however, there is a paucity of brain plasticity investigation after traumatic brain injury (TBI). This mini review summarizes the most recent evidence of brain plasticity in human TBI patients from the perspective of advanced magnetic resonance imaging. Similar to other forms of acquired brain injury, TBI patients also demonstrat-ed both structural reorganization as well as functional compensation by the recruitment of other brain regions. However, the large scale brain network alterations after TBI are still unknown, and the ifeld is still short of proper means on how to guide the choice of TBI rehabilitation or treat-ment plan to promote brain plasticity. The authors also point out the new direction of brain plas-ticity investigation.

  11. CT imaging of primary pleuropulmonary synovial sarcoma

    International Nuclear Information System (INIS)

    Aim: To evaluate the computed tomography (CT) imaging findings of primary pleuropulmonary synovial sarcoma. Materials and methods: Five cases of synovial sarcoma confirmed by histopathology and cytogenetic study were retrospectively analysed. All patients had undergone chest radiography and unenhanced and contrast-enhanced CT examinations, and three had also undergone multiphase CT enhancement examinations. Image characteristics, including shape, size, margin, and attenuation of each lesion before and after contrast enhancement, were analysed. Results: The chest radiographs of the five patients showed well-defined or partly well-defined masses, which were homogeneous and without associated calcification or lymphadenopathy. Pneumothorax was present in one patient. The unenhanced CT images showed well-defined, heterogeneous masses with patchy low density in all five patients. The contrast-enhanced CT images showed heterogeneous enhancement in all cases, three of which demonstrated cystic and necrotic areas. The tumour showed no prolonged or delayed enhancement in three cases using multiphase CT. There were small pleural effusions in four cases. No calcification was observed in any of the cases. There was no evidence of hilar or mediastinal lymphadenopathy. Conclusions: In these five patients, primary pleuropulmonary synovial sarcoma presented as a well-defined mass with patchy low density and heterogeneous enhancement, with no evidence of regional lymphadenopathy. It should be included in the differential diagnosis of regional tumours.

  12. Magnetic resonance imaging in diffuse brain injury

    International Nuclear Information System (INIS)

    Forty cases diagnosed as diffuse brain injury (DBI) were studied by magnetic resonance imaging (MRI) performed within 3 days after injury. These cases were divided into two groups, which were the concussion group and diffuse axonal injury (DAI) group established by Gennarelli. There were no findings on computerized tomography (CT) in the concussion group except for two cases which had a brain edema or subarachnoid hemorrhage. But on MRI, high intensity areas on T2 weighted imaging were demonstrated in the cerebral white matter in this group. Many lesions in this group were thought to be edemas of the cerebral white matter, because of the fact that on serial MRI, they were isointense. In mild types of DAI, the lesions on MRI were located only in the cerebral white matter, whereas, in the severe types of DAI, lesions were located in the basal ganglia, the corpus callosum, the dorsal part of the brain stem as well as in the cerebral white matter. As for CT findings, parenchymal lesions were not visualized especially in mild DAI. Our results suggested that the lesions in cerebral concussion were edemas in cerebral white matter. In mild DAI they were non-hemorrhagic contusion; and in severe DAI they were hemorrhagic contusions in the cerebral white matter, the basal ganglia, the corpus callosum or the dorsal part of the brain stem. (author)

  13. Magnetic resonance imaging in diffuse brain injury

    Energy Technology Data Exchange (ETDEWEB)

    Yokota, Hiroyuki; Yasuda, Kazuhiro; Mashiko, Kunihiro; Henmi, Hiroshi; Otsuka, Toshibumi; Kobayashi, Shiro; Nakazawa, Shozo (Nippon Medical School, Tokyo (Japan))

    1992-01-01

    Forty cases diagnosed as diffuse brain injury (DBI) were studied by magnetic resonance imaging (MRI) performed within 3 days after injury. These cases were divided into two groups, which were the concussion group and diffuse axonal injury (DAI) group established by Gennarelli. There were no findings on computerized tomography (CT) in the concussion group except for two cases which had a brain edema or subarachnoid hemorrhage. But on MRI, high intensity areas on T2 weighted imaging were demonstrated in the cerebral white matter in this group. Many lesions in this group were thought to be edemas of the cerebral white matter, because of the fact that on serial MRI, they were isointense. In mild types of DAI, the lesions on MRI were located only in the cerebral white matter, whereas, in the severe types of DAI, lesions were located in the basal ganglia, the corpus callosum, the dorsal part of the brain stem as well as in the cerebral white matter. As for CT findings, parenchymal lesions were not visualized especially in mild DAI. Our results suggested that the lesions in cerebral concussion were edemas in cerebral white matter. In mild DAI they were non-hemorrhagic contusion; and in severe DAI they were hemorrhagic contusions in the cerebral white matter, the basal ganglia, the corpus callosum or the dorsal part of the brain stem. (author).

  14. Brain CT scanning of children with purulent meningitis

    International Nuclear Information System (INIS)

    Nine of 21 children with purulent meningitis showed abnormal findings in brain CT when admitted. All of abnormal group were less than 12 months of age, but 75 % of normal group were after 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 similary in both groups, it may be hard to suggest the organic changes of brain by clinically. It will be better to perform brain CT scanning as soon as possible on the beginning of purulent meningitis. (author)

  15. Fetal trauma: brain imaging in four neonates

    International Nuclear Information System (INIS)

    The purpose of this paper is to describe brain pathology in neonates after major traffic trauma in utero during the third trimester. Our patient cohort consisted of four neonates born by emergency cesarean section after car accident in the third trimester of pregnancy. The median gestational age (n=4) was 36 weeks (range: 30-38). Immediate post-natal and follow-up brain imaging consisted of cranial ultrasound (n=4), computed tomography (CT) (n=1) and post-mortem magnetic resonance imaging (MRI) (n=1). Pathology findings were correlated with the imaging findings (n=3). Cranial ultrasound demonstrated a huge subarachnoidal hemorrhage (n=1), subdural hematoma (n=1), brain edema with inversion of the diastolic flow (n=1) and severe ischemic changes (n=1). In one case, CT demonstrated the presence and extension of the subarachnoidal hemorrhage, a parietal fracture and a limited intraventricular hemorrhage. Cerebellar hemorrhage and a small cerebral frontal contusion were seen on post-mortem MRI in a child with a major subarachnoidal hemorrhage on ultrasound. None of these four children survived (three children died within 2 days and one child died after 1 month). Blunt abdominal trauma during pregnancy can cause fetal cranial injury. In our cases, skull fracture, intracranial hemorrhage and hypoxic-ischemic encephalopathy were encountered. (orig.)

  16. Brain perfusion-CT in acute stroke patients

    International Nuclear Information System (INIS)

    Since 1979 when Grodfrey Hounsfield and Allan Corman introduced the computed tomography new generations of CT were developed that improved the special resolution and time of acquisition. The role of neuro-imaging in the evaluation of acute stroke has changed dramatically in the past decade. Previously, neuro-imaging was used in this set-ting to provide anatomic imaging that indicated the presence or absence of acute cerebral ischemia and excluded lesions that produce symptoms or signs mimicking those of stroke, such as hemorrhage and neoplasms. More recently, the introduction of thrombolysis has changed the goals of neuro-imaging from providing solely anatomic information to providing physiologic information that could help to determine which patients might benefit from therapy. In particular, significant emphasis has been placed on the delineation of the ischemic penumbra, also called tissue at risk. Modem CT survey, consisting of three indissociable elements; noncontrast CT (NCT) of course, perfusion-CT (PCT) and CT-angiography (CTA), fulfill all the requirements for hyperacute stroke imaging. CTA can define the occlusion site, depict arterial dissection, grade collateral blood flow, and characterize atherosclerotic disease, whereas PCT accurately defines the infarct core and the ischemic penumbra. CT offers a number of practical advantages over other cerebral perfusion imaging methods, including its wide availability. Using PCT and CTA to define new individualized strategies for acute reperfusion will allow more acute stroke patients to benefit from thrombolytic therapy. Key words: Stroke. Penumbra. Computed Tomography. Perfusion-CT. CT Angiography. Outcome

  17. Whole-brain CT perfusion and CT angiography assessment of Moyamoya disease before and after surgical revascularization: preliminary study with 256-slice CT.

    Directory of Open Access Journals (Sweden)

    Jun Zhang

    Full Text Available BACKGROUND/AIMS: The 256-slice CT enables the entire brain to be scanned in a single examination. We evaluated the application of 256-slice whole-brain CT perfusion (CTP in determining graft patency as well as investigating cerebral hemodynamic changes in Moyamoya disease before and after surgical revascularization. METHODS: Thirty-nine cases of Moyamoya disease were evaluated before and after surgical revascularization with 256-slice CT. Whole-brain perfusion images and dynamic 3D CT angiographic images generated from perfusion source data were obtained in all patients. Cerebral blood flow (CBF, cerebral blood volume (CBV, time to peak (TTP and mean transit time (MTT of one hemisphere in the region of middle cerebral artery (MCA distribution and contralateral mirroring areas were measured. Relative CTP values (rCBF, rCBV, rTTP, rMTT were also obtained. Differences in pre- and post- operation perfusion CT values were assessed with paired t test or matched-pairs signed-ranks test. RESULTS: Preoperative CBF, MTT and TTP of potential surgical side were significantly different from those of contralateral side (P<0.01 for all. All graft patencies were displayed using the 3D-CTA images. Postoperative CBF, rCBF and rCBV values of surgical side in the region of MCA were significantly higher than those before operation (P<0.01 for all. Postoperative MTT, TTP, rMTT and rTTP values of the surgical side in the region of MCA were significantly lower than those before operation (P<0.05 for all. CONCLUSION: The 256-slice whole-brain CTP can be used to evaluate cerebral hemodynamic changes in Moyamoya disease before and after surgery and the 3D-CTA is useful for assessing the abnormalities of intracranial arteries and graft patencies.

  18. CT image processing using digital networks

    International Nuclear Information System (INIS)

    Several digital image transmission networks have been proposed, studied, and measured for local-area medical applications. The image processing service described here uses a commercial digital network to connect the computers of CT scanners. The network service shares image processing tasks with remote sites during the times that the scanners are otherwise idle. The network is nationwide, emphasizes resource sharing, uses moderate-bandwidth (4800 or 9600 baud, i.e., 480 or 960 characters/sec) dedicated leased telephone lines, and is restricted at this time to only a few types of CT scanner. Furthermore, because it offers services that are not interactive, it is able to optimize computer resources without routine interruption from users. Discussion begins by a brief overview of classic computer network topologies, with an emphasis on their application to CT, magnetic resonance imaging (MRI), and other medical imaging modalities. This somewhat technical introduction to networks demonstrates the unique characteristics of medical image communication as opposed to the more common applications of computer communication in the banking, retail, and management information industries. In the sections that follow, a more selective focus is made on the topology, hardware, image-processing, and operational characteristics of a network that is now composed of over 50 CT scanner systems throughout the United States. The chapter concludes by summarizing the network performance during its first 35 months of operation

  19. Improving image quality in portal venography with spectral CT imaging

    International Nuclear Information System (INIS)

    Objective: To investigate the effect of energy spectral CT on the image quality of CT portal venography in cirrhosis patients. Materials and methods: 30 portal hypertension patients underwent spectral CT examination using a single-tube, fast dual tube voltage switching technique. 101 sets of monochromatic images were generated from 40 keV to 140 keV. Image noise and contrast-to-noise ratio (CNR) for portal veins from the monochromatic images were measured. An optimal monochromatic image set was selected for obtaining the best CNR for portal veins. The image noise and CNR of the intra-hepatic portal vein and extra-hepatic main stem at the selected monochromatic level were compared with those from the conventional polychromatic images. Image quality was also assessed and compared. Results: The monochromatic images at 51 keV were found to provide the best CNR for both the intra-hepatic and extra-hepatic portal veins. At this energy level, the monochromatic images had about 100% higher CNR than the polychromatic images with a moderate 30% noise increase. The qualitative image quality assessment was also statistically higher with monochromatic images at 51 keV. Conclusion: Monochromatic images at 51 keV for CT portal venography could improve CNR for displaying hepatic portal veins and improve the overall image quality.

  20. Improving image quality in portal venography with spectral CT imaging

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Li-qin, E-mail: zhaolqzr@sohu.com [Department of Radiology, Beijing Friendship Hospital Affiliated to Capital Medical University, Beijing,100050 (China); He, Wen, E-mail: hewen1724@sina.com [Department of Radiology, Beijing Friendship Hospital Affiliated to Capital Medical University, Beijing,100050 (China); Li, Jian-ying, E-mail: jianying.li@med.ge.com [CT Advanced Application and Research, GE Healthcare, 100176 China (China); Chen, Jiang-hong, E-mail: chenjianghong1973@hotmail.com [Department of Radiology, Beijing Friendship Hospital Affiliated to Capital Medical University, Beijing,100050 (China); Wang, Ke-yang, E-mail: ke7ke@sina.com [Department of Radiology, Beijing Friendship Hospital Affiliated to Capital Medical University, Beijing,100050 (China); Tan, Li, E-mail: Litan@ge.com [CT product, GE Healthcare, 100176 China (China)

    2012-08-15

    Objective: To investigate the effect of energy spectral CT on the image quality of CT portal venography in cirrhosis patients. Materials and methods: 30 portal hypertension patients underwent spectral CT examination using a single-tube, fast dual tube voltage switching technique. 101 sets of monochromatic images were generated from 40 keV to 140 keV. Image noise and contrast-to-noise ratio (CNR) for portal veins from the monochromatic images were measured. An optimal monochromatic image set was selected for obtaining the best CNR for portal veins. The image noise and CNR of the intra-hepatic portal vein and extra-hepatic main stem at the selected monochromatic level were compared with those from the conventional polychromatic images. Image quality was also assessed and compared. Results: The monochromatic images at 51 keV were found to provide the best CNR for both the intra-hepatic and extra-hepatic portal veins. At this energy level, the monochromatic images had about 100% higher CNR than the polychromatic images with a moderate 30% noise increase. The qualitative image quality assessment was also statistically higher with monochromatic images at 51 keV. Conclusion: Monochromatic images at 51 keV for CT portal venography could improve CNR for displaying hepatic portal veins and improve the overall image quality.

  1. Progress in imaging of brain radiation injury

    International Nuclear Information System (INIS)

    The mechanisms of brain radiation injury mainly include three hypotheses: vascular injury, glial cells damage and immune response. Most scholars' studies have recently supported the former two ones. Vascular injury plays a major role in the effect of delayed radiation injury. Focal brain injury and diffuse white matter injury can be definitely diagnosed by CT and MRI. T2-weighted imaging (T2WI) in MRI shows high sensitivity in water contents, and is not affected by the beam hardening artifacts from the cranial base. Compared with CT, the sensitivity of MR for detecting white matter lesions is two to threefold higher. When lesions occurs at the site of an irradiated cerebral tumor, tumor recurrence and focal cerebral necrosis cannot be differentiated by CT or MR, PET and MRS now present a certain advantage of differential diagnosis. Tumor presents high metabolism and necrosis demonstrates low metabolism by utilizing PET scanning, however PET's sensitivity and specificity are far from satisfactory. The amount or ratio of metabolic products in the region of interest measured by MRS contributes to the deferential diagnosis. In addition, PET functional imaging and MRS can also predict the early asymptomatic reversible radiation injury so as to allow the early therapy of steroids and possibly other drugs, prior to the development of irreversible changes

  2. Intraoperative CT imaging system using a mobile CT scanner gantry mounted on floor-embedded rails for neurosurgery

    Energy Technology Data Exchange (ETDEWEB)

    Kabuto, Masanori; Kubota, Toshihiko; Kobayashi, Hidenori [Fukui Medical Univ., Matsuoka (Japan)] [and others

    1998-11-01

    Many neurosurgeons prefer to use intraoperative computed tomographic (CT) scanning, when possible, to check whether there is residual lesion or unexpected bleeding. We report a practical intraoperative CT imaging system using a high-speed CT scanner installed in the operating room along with a digitally controlled neurosurgical operating table. We designed a rail-track system to mobilize the CT gantry. The gantry is fixed onto a motorized carrier that can be moved smoothly on a rail-track embedded in the floor and with a maximum reach of 2.85 m from the room`s wall to the operating table. The longitudinal motion of the operating table is easily adjusted by a foot switch from manual control to automatic control directly from the CT scanner`s computer like an ordinary CT scanner bed in increments of 2, 5 or 10 mm during CT scanning. Either a carbon-made radiolucent head frame or carbon-made head plate is used as a headrest. Using this CT scanner system, pre- and intraoperative CT scannings were performed on 46 patients with brain tumors, cervical lesions or other intracranial lesions. We could operate on the patient with enough working space between the mobile CT gantry and the operating table for microneurosurgery. We could obtain intraoperative CT imaging of a patient on the operating table while the surgical wound remained open, the surgical drapes kept in place, and the surgical position unchanged, saving time in intraoperative CT scanning and preparation for further surgery when needed. This intraoperative CT imaging system installed in the operating room should be useful for neurosurgery. (author)

  3. Intraoperative CT imaging system using a mobile CT scanner gantry mounted on floor-embedded rails for neurosurgery

    International Nuclear Information System (INIS)

    Many neurosurgeons prefer to use intraoperative computed tomographic (CT) scanning, when possible, to check whether there is residual lesion or unexpected bleeding. We report a practical intraoperative CT imaging system using a high-speed CT scanner installed in the operating room along with a digitally controlled neurosurgical operating table. We designed a rail-track system to mobilize the CT gantry. The gantry is fixed onto a motorized carrier that can be moved smoothly on a rail-track embedded in the floor and with a maximum reach of 2.85 m from the room's wall to the operating table. The longitudinal motion of the operating table is easily adjusted by a foot switch from manual control to automatic control directly from the CT scanner's computer like an ordinary CT scanner bed in increments of 2, 5 or 10 mm during CT scanning. Either a carbon-made radiolucent head frame or carbon-made head plate is used as a headrest. Using this CT scanner system, pre- and intraoperative CT scannings were performed on 46 patients with brain tumors, cervical lesions or other intracranial lesions. We could operate on the patient with enough working space between the mobile CT gantry and the operating table for microneurosurgery. We could obtain intraoperative CT imaging of a patient on the operating table while the surgical wound remained open, the surgical drapes kept in place, and the surgical position unchanged, saving time in intraoperative CT scanning and preparation for further surgery when needed. This intraoperative CT imaging system installed in the operating room should be useful for neurosurgery. (author)

  4. Optimized Discretization Schemes For Brain Images

    Directory of Open Access Journals (Sweden)

    USHA RANI.N,

    2011-02-01

    Full Text Available In medical image processing active contour method is the important technique in segmenting human organs. Geometric deformable curves known as levelsets are widely used in segmenting medical images. In this modeling , evolution of the curve is described by the basic lagrange pde expressed as a function of space and time. This pde can be solved either using continuous functions or discrete numerical methods.This paper deals with the application of numerical methods like finite diffefence and TVd-RK methods for brain scans. The stability and accuracy of these methods are also discussed. This paper also deals with the more accurate higher order non-linear interpolation techniques like ENO and WENO in reconstructing the brain scans like CT,MRI,PET and SPECT is considered.

  5. CONTRAST STUDY ON CT AND BA IN DIAGNOSIS OF PATIENTS WITH ATHEROTHROMBOTIC BRAIN INFARCTION

    Institute of Scientific and Technical Information of China (English)

    Mingshun Liu; Haixiang Gao; Xiaomei Fu; Po Ma

    2007-01-01

    Objectives: To explore applied value on CT and BA in diagnosis of patients with atherothrombotic brain infarction. Methods:CT and BA were examined in 246 patients with atherothrombotic brain infarction. Results:The different change of CT and BA were showed in 246 patients with atherothrombotic brain infarction. Conclusions: There were separately different advantage and shortcoming in CT and BA in diagnosis of atherothrombotic brain infarction. The value of clinical application of BA was important in diagnosis of atherothrombotic brain infarction.

  6. Brain CT findings of severely multiple handicapped children

    International Nuclear Information System (INIS)

    Brain CT were performed in 63 severely multiple handicapped children (30 males and 33 females) ranging in age from 2 to 21 years. Abnormal findings including ventricular dilatation and cortical atrophy were detected in 56 of the patients (88.9%). There was no specific finding for athetosis type cerebral palsy. There was no constant relationship between underlying diseases and CT findings.(Namekawa, K.)

  7. Radiation risk to critical organ during brain CT

    International Nuclear Information System (INIS)

    Study was performed to evaluate dose to critical organ for patient undergoing CT brain in modern medical center a total of 61 patient were examined in this study. The data collected from Modern Medical Center for brain. The data collected from Modern Medical Center for brain. The eye lens dose was 31.31 mSv, skin 29.23 mSv, cranium 30.01 mSv, brain 34.50 mSv, mandible 4.39 mSv, thyroid 2.59 mSv. The organ dose value were comparable to the previous studies. (Author)

  8. Imaging visual function of the human brain

    International Nuclear Information System (INIS)

    Imaging of human brain structure and activity with particular reference to visual function is reviewed along with methods of obtaining the data including computed tomographic (CT) scan, magnetic resonance imaging (MRI), magnetic resonance spectroscopy (MRS), and positron emission tomography (PET). The literature is reviewed and the potential for a new understanding of brain visual function is discussed. PET is reviewed from basic physical principles to the most recent visual brain findings with oxygen-15. It is shown that there is a potential for submillimeter localization of visual functions with sequentially different visual stimuli designed for the temporal separation of the responses. Single photon emission computed tomography (SPECT), a less expensive substitute for PET, is also discussed. MRS is covered from basic physical principles to the current state of the art of in vivo biochemical analysis. Future possible clinical applications are discussed. Improved understanding of the functional neural organization of vision and brain will open a window to maps and circuits of human brain function.119 references

  9. An improved image algorithm for CT scanners

    International Nuclear Information System (INIS)

    A common artifact in CT head-section images is a cupping or broad ''whitening'' effect near the skull which is due at least in part to the polychromaticity of the x-ray beam. In this paper, a general method is presented for removing this artifact empirically by a combination of two approaches. The gross cupping is removed by modifying the raw transmission data prior to reconstruction. The residual whitening near the bone is removed by conveniently modifying the reconstruction-filter function. Examples of the modifications are shown using the ASE CT scanner. The method convolves or deconvolves the CT image with an appropriate point spread function. Since the filter-function modifications conceptually done in real space rather than in frequency space, the details of the modifications are more easily understood

  10. Hybrid SPECT/CT imaging in neurology.

    Science.gov (United States)

    Ciarmiello, Andrea; Giovannini, Elisabetta; Meniconi, Martina; Cuccurullo, Vincenzo; Gaeta, Maria Chiara

    2014-01-01

    In recent years, the SPECT/CT hybrid modality has led to a rapid development of imaging techniques in nuclear medicine, opening new perspectives for imaging staff and patients as well. However, while, the clinical role of positron emission tomography-computed tomography (PET-CT) is well consolidated, the diffusion and the consequent value of single-photon emission tomography-computed tomography (SPECT-CT) has yet to be weighed, Hence, there is a need for a careful analysis, comparing the "potential" benefits of the hybrid modality with the "established" ones of the standalone machine. The aim of this article is to analyze the impact of this hybrid tool on the diagnosis of diseases of the central nervous system, comparing strengths and weaknesses of both modalities through the use of SWOT analysis. PMID:25143053

  11. Registration of SPECT, PET and/or X-ray CT images in patients with lung cancer

    International Nuclear Information System (INIS)

    Aim: In order to evaluate the therapeutic gain of heavy ion therapy performed on patients with lung cancer, the regional pulmonary functions and the amount of radio tracer accumulation to the tumor, we are investigated by using the region of interest based on anatomical information obtained from X-ray CT. There are many registration techniques for brain images, but not so much for the other organ images that we have studied registration of chest SPECT, PET and/or X-ray CT images. Materials and Methods: Perfusion, ventilation and blood pool images with Tc99m labeled radiopharmaceuticals and SPECT, tumor images with 11C-methionine and PET and X-ray CT scans were performed on several patients with lung cancer before and after heavy ion therapy. The registrations of SPECT-CT, PET-CT and CT-CT were performed by using AMIR (Automatic Multimodality Image Registration), which was developed by Babak et al. for registration of brain images. In a case of SPECT-CT registration, each of the three functional images was registered to the X-ray CT image, and the accuracy of each registration was compared. In the studies of PET-CT registration, the transmission images and X-ray CT images were registered at first, because the 11C-methionine PET images bear little resemblance to the underlying anatomical images. Next, the emission images were realigned by using the same registration parameters. The X-ray CT images obtained from a single subject at the different time were registered to the first X-ray CT images, respectively. Results: In the SPECT-CT registration, the blood pool-CT registration is the best among three SPECT images in visual inspection by radiologists. In the PET-CT registration, the Transmission-CT registrations got good results. Therefore, Emission-CT registrations also got good results. In the CT-CT registration, the X-ray CT images obtained from a single subject at the different time were superimposed well each other except for lower lobe. As the results, it was

  12. Appearance and impact of post-operative intracranial clips and coils on whole-brain CT angiography and perfusion

    International Nuclear Information System (INIS)

    Background: To evaluate the effect of vascular clips and endovascular coils placed for intracranial aneurysms and arteriovenous malformations on whole-brain computed tomography (CT) angiography and perfusion. Methods: A 320-detector row dynamic volume CT system imaged 11 patients following surgical placement of vascular clips or endovascular coils. The extent of clip and coil subtraction by automated software was evaluated using CT digital subtraction angiography and CT perfusion. Impact on CT perfusion values by retained intracranial devices was compared to age- and gender-matched controls. Results: Clip and coil subtraction on CT angiography was graded as good in 8 and moderate in 3 cases. A residual neck and additional aneurysm were noted in 1 of 11 patients. Post-procedural axial slice level CT perfusion values decreased in reliability with increasing proximity to the metallic devices secondary to beam hardening. However, the intracranial devices did not affect axial slice level CTP values of cerebral blood volume, cerebral blood flow and mean transit time outside of the level of the device. Time to peak values was globally decreased outside of the immediate vascular intervention region. Conclusions: Advances in CT technology have provided clinically useful subtraction of intracranial clips and coils. While CT perfusion values were altered in device subtraction areas and within beam hardening artifact areas; they can provide valuable postoperative information on whole-brain hemodynamics. In selected cases, the combination of CT angiography and whole-brain CT perfusion can offer an alternative to conventional angiography that is a more invasive option.

  13. Techniques in Iterative Proton CT Image Reconstruction

    CERN Document Server

    Penfold, Scott

    2015-01-01

    This is a review paper on some of the physics, modeling, and iterative algorithms in proton computed tomography (pCT) image reconstruction. The primary challenge in pCT image reconstruction lies in the degraded spatial resolution resulting from multiple Coulomb scattering within the imaged object. Analytical models such as the most likely path (MLP) have been proposed to predict the scattered trajectory from measurements of individual proton location and direction before and after the object. Iterative algorithms provide a flexible tool with which to incorporate these models into image reconstruction. The modeling leads to a large and sparse linear system of equations that can efficiently be solved by projection methods-based iterative algorithms. Such algorithms perform projections of the iterates onto the hyperlanes that are represented by the linear equations of the system. They perform these projections in possibly various algorithmic structures, such as block-iterative projections (BIP), string-averaging...

  14. CT imaging of necrosive fasciitis

    International Nuclear Information System (INIS)

    NF is a rare but dramatic and often fatal infection of the fascii and adjoining soft tissues. Contrary to the Fournier's definition, it is most common in elderly people. Patients with immune problems have a higher risk (e.g. Diabetes mellitus, alcohol or drug abuse, AIDS, leukaemia, chemotherapy and immunosuppressive medication). Predisposition factors are diverticulitis, insect bites, or surgical interventions (Uppot RN, Levy HM, PLatel PH, Radiology 2003; 226; 115; Wysoki MG, Santora TA, Shah RM et al. Necrotizing fasciitis: CT characteristics, Radiology 1997; 203;859). Men are affected more frequently than women. In principle, NF may occur everywhere in the body but incidence in the region of the scrotum, perineum and lower extremities are the most common. (orig.)

  15. Determining ablation depth using CT imaging

    Czech Academy of Sciences Publication Activity Database

    Urzová, J.; Jelínek, Miroslav; Remsa, Jan; Vopálka, R.

    Kladno: CTU Faculty of Biomedical Engineering, 2015 - (Jelínek, M.). s. 17 ISBN 978-80-01-05809-1. [Progressive Biomedical Materials and Technologies 2015. 09.10.2015-10.10.2015, Kladno] Institutional support: RVO:68378271 Keywords : ablation depth * CT imaging * excimer laser Subject RIV: BM - Solid Matter Physics ; Magnetism

  16. CT与MRI图像融合对脑转移瘤三维适形放疗靶区的影响%The influence of target volume by CT/MRI image fusion on brain metastasis's three-dimensional conformal radiotherapy

    Institute of Scientific and Technical Information of China (English)

    陈苏玮; 袁锋; 林志仁; 王伟锋

    2012-01-01

    Objective To improve the accuracy of delineating three-dimensional conformal radiotherapy target volume by comparing the difference between computed tomography(CT)/magnetic resonance imaging (MRI) image fusion on brain metastasis area and CT's target area. Methods CT's images and MRI's images collected from 25 cases with brain metastasis in the same period were transmitted to image processing workstation and fused into CT/MRI images, and then 41 pairs of gross tumor volume (GTV) were delineated in CT and CT/MRI, and finally difference was compared between the two group. Results The value of GTVCT in 41 pairs from 25 cases was (31.75±9.93) cm3 and in GTVCT/MRI was (28.92±8.25) cm3. Among 41 control groups, the number of the accuracy of GTVCT lower than that of GTVCT/MRI was 18, GTCCT higher than that of GTVCT/MRI was 23. Conclusion The improving accuracy of brain metastasis's target volume sketched by CT/MRI image fusion is more suitable for three-dimensional conformal radiotherapy.%目的 研究CT与MRI图像融合的脑转移瘤靶区与CT图像靶区的不同,提高三维适形放疗靶区勾画的准确性.方法 同期采集25例脑转移瘤患者的CT和MRI图像,传送至图像处理工作站融合成CT/MRI图像,分别在CT及CT/MRI融合图像勾画41组GTV,比较两种图像勾画的GTV的差别.结果 25例患者共41组靶区的GTVcr为(31.75±9.93)cm3,GTVCT/MRI为(28.92±8.25)cm3.41个对照组中,GTVCr <GTVCT/MRI为18个,GTVCT >GTVCT/MRI为23个.结论 采用CT/MRI融合后图像勾画的脑转移瘤靶区精确度提高,更适合于三维立体适形放疗.

  17. Imaging spectrum of adrenal pseudocysts on CT

    International Nuclear Information System (INIS)

    The aim of this study was to analyze the imaging spectrum of adrenal pseudocysts on CT. The CT images of seven patients with pathologic diagnosis of adrenal pseudocysts in our hospital were reviewed for the size, cystic part, solid part, septum, calcification, acute hematoma, and layering appearance. The presence or absence of contrast enhancement of solid parts in each lesion was also assessed if possible. Of the seven adrenal pseudocysts, there were three pure cystic, three mixed cystic and solid, and one solid lesions on CT. Two of the three cystic pseudocysts were septated with calcifications. Layering appearance was present in two mixed lesions. There were central calcifications and acute hematomas in one solid mass. In our study, there was no contrast enhancement of the solid parts of adrenal pseudocysts. The CT appearances of adrenal pseudocysts may range from cystic, mixed, to solid masses. The presence of solid parts of adrenal pseudocysts on CT mimics those of adrenal neoplasms; however, no contrast enhancement of the solid part in the lesion may help in the diagnosis of adrenal pseudocysts and their differentiation from adrenal neoplasms. (orig.)

  18. Hybrid scatter correction for CT imaging

    International Nuclear Information System (INIS)

    The purpose of this study was to develop and evaluate the hybrid scatter correction algorithm (HSC) for CT imaging. Therefore, two established ways to perform scatter correction, i.e. physical scatter correction based on Monte Carlo simulations and a convolution-based scatter correction algorithm, were combined in order to perform an object-dependent, fast and accurate scatter correction. Based on a reconstructed CT volume, patient-specific scatter intensity is estimated by a coarse Monte Carlo simulation that uses a reduced amount of simulated photons in order to reduce the simulation time. To further speed up the Monte Carlo scatter estimation, scatter intensities are simulated only for a fraction of all projections. In a second step, the high noise estimate of the scatter intensity is used to calibrate the open parameters in a convolution-based algorithm which is then used to correct measured intensities for scatter. Furthermore, the scatter-corrected intensities are used in order to reconstruct a scatter-corrected CT volume data set. To evaluate the scatter reduction potential of HSC, we conducted simulations in a clinical CT geometry and measurements with a flat detector CT system. In the simulation study, HSC-corrected images were compared to scatter-free reference images. For the measurements, no scatter-free reference image was available. Therefore, we used an image corrected with a low-noise Monte Carlo simulation as a reference. The results show that the HSC can significantly reduce scatter artifacts. Compared to the reference images, the error due to scatter artifacts decreased from 100% for uncorrected images to a value below 20% for HSC-corrected images for both the clinical (simulated data) and the flat detector CT geometry (measurement). Compared to a low-noise Monte Carlo simulation, with the HSC the number of photon histories can be reduced by about a factor of 100 per projection without losing correction accuracy. Furthermore, it was sufficient to

  19. CT and MR imaging features in patients with intracranial dolichoectasia

    Energy Technology Data Exchange (ETDEWEB)

    Tien, Kuang Lung; Yu, In Kyu; Yoon, Sook Ja; Yoon, Yong Kyu [Eulji College of Medicine, Eulji Hospital, Seoul (Korea, Republic of)

    2000-02-01

    To describe the CT and MR imaging features in patients with intracranial dolichoectasia. The CT (n=3D21), MR (n=3D20) and MRA (n=3D11) imaging features seen in 28 patients (M:F=3D12:16 aged between 65 and 82 (mean, 65) years) with intracranial dolichoectasia were retrospectively reviewed with regard to involved sites, arterial changes (maximum diameter, wall calcification, high signal intensity in the involved artery, as seen on T1-weighted MR images), infarction, hemorrhagic lesion, compression of brain parenchyma or cranial nerves, hydrocephalus and brain atrophy. Involved sites were classified as either type 1 (involvement of only the posterior circulation), type 2 (only the anterior circulation), or type 3 (both). In order of frequency, involved sites were type 1 (43%), type 3 (36%) and type 2 (22%). Dolichoectasia was more frequently seen in the posterior circulation (79%) than in the anterior (57%). Arterial changes as seen on T1-weighted MR images, included dolichoectasia (mean maximum diameter 7.4 mm in the distal internal carotid artery, and 6.7 mm in the basilar artery), wall calcification (100% in involved arteries) and high signal intensity in involved. Cerebral infarction in the territory of the involved artery was found in all patients, and a moderate degree of infarct was 87%. Hemorrhagic lesions were found in 19 patients (68%); these were either lobar (53%), petechial (37%), or subarachnoid (16%), and three patients showed intracranial aneurysms, including one case of dissecting aneurysm. In 19 patients (68%), lesions were compressed lesions by the dolichoectatic arteries, and were found-in order of descending frequency-in the medulla, pons, thalamus, and cerebellopontine angle cistern. Obstructive hydrocephalus was found in two patients (7%), and 23 (82%) showed a moderate degree of brain atrophy. In patients with intracranial dolichoectasia, moderate degrees of cerebral infarction and brain atrophy in the territory of involved arteries, as well as

  20. CT and MR imaging features in patients with intracranial dolichoectasia

    International Nuclear Information System (INIS)

    To describe the CT and MR imaging features in patients with intracranial dolichoectasia. The CT (n=3D21), MR (n=3D20) and MRA (n=3D11) imaging features seen in 28 patients (M:F=3D12:16 aged between 65 and 82 (mean, 65) years) with intracranial dolichoectasia were retrospectively reviewed with regard to involved sites, arterial changes (maximum diameter, wall calcification, high signal intensity in the involved artery, as seen on T1-weighted MR images), infarction, hemorrhagic lesion, compression of brain parenchyma or cranial nerves, hydrocephalus and brain atrophy. Involved sites were classified as either type 1 (involvement of only the posterior circulation), type 2 ( only the anterior circulation), or type 3 (both). In order of frequency, involved sites were type 1 (43%), type 3 (36%) and type 2 (22%). Dolichoectasia was more frequently seen in the posterior circulation (79%) than in the anterior (57%). Arterial changes as seen on T1-weighted MR images, included dolichoectasia (mean maximum diameter 7.4 mm in the distal internal carotid artery, and 6.7 mm in the basilar artery, wall calcification (100% in involved arteries) and high signal intensity in involved. Cerebral infarction in the territory of the involved artery was found in all patients, and a moderate degree of infarct was 87%. Hemorrhagic lesions were found in 19 patients (68%); these were either lobar (53%), petechial (37%), or subarachnoid (16%), and three patients showed intracranial aneurysms, including one case of dissecting aneurysm. In 19 patients (68%), lesions were compressed lesions by the dolichoectatic arteries, and were found-in order of descending frequency-in the medulla, pons, thalamus, and cerebellopontine angle cistern. Obstructive hydrocephalus was found in two patients (7%), and 23 (82%) showed a moderate degree of brain atrophy. In patients with intracranial dolichoectasia, moderate degrees of cerebral infarction and brain atrophy in the territory of involved arteries, as well as

  1. 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)

  2. Imaging of abdominal tumours: CT or MRI?

    International Nuclear Information System (INIS)

    The scope of this review is to discuss a theoretical approach to imaging policy, particularly in the perspective of radiation risk reduction. Decisions are ideally driven by empirical evidence about efficacy and risk, e.g., in classical hierarchical efficacy model. As a result of the paucity of empirical evidence (inevitable because of rapid technological development), a pragmatic model is needed. This should avoid overemphasis of factors that currently seem to hamper change, namely personal preference, local expertise, infrastructure, availability. Extrapolation of current general knowledge about CT and MRI demonstrates how a pragmatic approach can be applied in the real world with intermediate goals such as (1) channeling patients from CT to MRI, and (2) reducing CT-delivered radiation. Increased utilisation of MRI in body imaging requires optimisation of scan protocols and equipment, and, being a very operator-dependent modality, the active involvement of the radiologist. In CT dose reduction the main challenge is to benchmark the minimum radiation-dose requirement, and therefore the minimum required image quality that is diagnostically acceptable. As this will ultimately depend on pre-test likelihoods in institutional populations, it is difficult to issue general guidance, and local assessment remains a cornerstone in this effort. (orig.)

  3. CT images of unilateral sinus lesions

    International Nuclear Information System (INIS)

    Computed tomographic images of 49 cases of unilateral sinus lesions were examined, and 4 findings were obtained as follows; 1) On the C.T. images of malignant tumors, detection of bone destruction was easy, but its early erosion was difficult. 2) Fungus infections and papilloma of paranasal sinuses demonstrated bone thickness as well as destruction, and this finding would serve as a differential point from malignant diseases. 3) From the C.T. values of soft tissue shadows in the maxillary sinus, it was impossible to differentiate malignant from benign lesions. However, a calcified or non-homogenous soft tissue shadow was seen only in cases of fungus infections and maxillary adenocarcinoma in malignant tumors, and it would be clinically a very important differential point. 4) Many of the unilateral sinus lesions will prove to be indications for surgery, except acute and allergic sinusitis. The paranasal C.T. examinations should be performed if the case does not respond to a conservative therapy over a month, and a case showing bone destruction by the C.T. images would require an exploratory Caldwell-Luc operation. (author)

  4. Clinical and pathological significance of carotid siphon calcification observed on bone condition of brain CT

    International Nuclear Information System (INIS)

    On plain brain computed tomography (CT), it is difficult to evaluate stenosis of internal carotid artery (ICA) because ICA is surrounded by structures, even though we can observe calcification of carotid siphon in some patients by using bone condition. However the pathologic significance has not been well known. We studied the pathologic significance of carotid siphon calcification observed on bone condition of brain CT. A total of 112 patients who were diagnosed or suspected as cerebrovascular diseases were registered. We classified the calcification into four levels (none, mild, moderate, severe) based on the degree of calcification. Then we compared it with the degree of stenosis of carotid siphon seen on brain magnetic resonance angiography (MRA) and with max intima-medial thickness (IMT) from common carotid artery (CCA) to ICA on carotid ultrasonography. The mean±standard deviation of max IMT to none, mild, moderate and severe in the degree of calcification were 1.03±0.64 (0.4-2.8), 1.65±0.83 (0.5-4.1), 2.03±0.83 (0.8-4.1) and 2.81±1.15 (0.7-6.5) mm, respectively. The calcification on brain CT significantly correlated with the degree of stenosis on brain MRA and with max IMT on carotid ultrasonography. The calcification of carotid siphon on bone condition of brain CT correlated with stenosis of the same portion and atherosclerosis of CCA bifurcation. Recently, on Digital Imaging and Communications in Medicine (DICOM) viewer, clinicians can convert plain condition into bone condition on brain CT due to popularization of picture achieving and communication system (PACS). We should pay attention to calcification of carotid siphon in patients with ischemic cerebrovascular diseases because we can estimate the atherosclerosis of both carotid siphon and CCA bifurcation easily and immediately. (author)

  5. ''Routine'' brain CT in psychiatric patients - does it make sense?

    International Nuclear Information System (INIS)

    Purpose: To prospectively assess the spectrum of brain CT findings in psychiatric patients and to determine the number of patients that had an underlying cause for the symptoms. Patients and methods: Over a period of six months, 142 patients (78 males, 64 females; median age 61 [18-91] years) were referred for CT brain scans. Their scans were reviewed, along with the clinical information that was provided in the request form. All the hard copies were reviewed to assess areas of ischaemia, infarction, atrophy, tumours, and haematomas. The majority of requests were to exclude vascular event or space-occupying lesions. Clinical indications included mood disorders (depression, mania), schizophrenic disorders, dementia, personality and behavioural disorders. Results: 31 (22%) were normal. 111 (78%) had varying degrees of ischaemia, infarction and cerebral/cerebellar atrophy. 7 (4.9%) had space-occupying lesions which included two gliomas and five meningiomas. There were two chronic subdural haematomas and one arteriovenous malformation. Conclusion: 1. In our series, pathologic findings in 'routine' brain CT's were encountered in 78%. 2. The incidence of brain tumours was 4.9%, compared with 0.00005% of the general population. 3. CT scanning in psychiatric patients is cost-effective and especially indicated when there is an atypical presentation, or inadequate response to standard treatment. (orig.)

  6. Method of injection of contrast medium for brain perfusion CT

    International Nuclear Information System (INIS)

    Perfusion computed tomography (CT) has great value for detecting stroke and evaluating blood flow in the brain. With perfusion CT, it is possible to obtain two absolute values, cerebral blood flow (CBF) (ml/min/100 g) and cerebral blood volume (CBV) (%). In using this examination, the main problem is the method of iodine injection. The maximum slope of time-attenuation curve in organs must be reached before the peak enhancement time of the sagittal sinus. To solve this problem, we used a new method in which total injection volume is 30 ml, and the rate of injection is 9 ml/sec. The data acquisition time is one second for each scan, and the time interval is one second, for 20 scans in total. With this method, we can obtain reliable information on blood flow in the damaged brain. The most common examination used for the detection of brain blood flow is single-phased dynamic CT with Xe inhalation. However, the Xe inhalant examination is difficult to use in the routine clinical setting. Perfusion CT will be more useful for the detection of brain blood flow. (author)

  7. Accuracy of radiographer reporting of paediatric brain CT

    International Nuclear Information System (INIS)

    Radiographer reporting has been studied for plain films and for ultrasonography, but not in paediatric brain CT in the emergency setting. To study the accuracy of radiographer reporting in paediatric brain CT. We prospectively collected 100 paediatric brain CT examinations. Films were read from hard copies using a prescribed tick sheet. Radiographers with 12 years' and 3 years' experience, respectively, were blinded to the history and were not trained in diagnostic film interpretation. The radiographers' results were compared with those of a consultant radiologist. Three categories were defined: abnormal scans, significant abnormalities and insignificant abnormalities. Both radiographers had an accuracy of 89.5% in reading a scan correctly as abnormal, and radiographer 1 had a sensitivity of 87.8% and radiographer 2 a sensitivity of 96%. Radiographer 1 had an accuracy in detecting a significant abnormality of 75% and radiographer 2 an accuracy of 48.6%, and the sensitivities for this category were 61.6% and 52.9%, respectively. Results for detecting the insignificant abnormalities were poorer. Selected radiographers could play an effective screening role, but lacking the sensitivity required for detecting significant abnormality, they could not be the final diagnostician. We recommend that the study be repeated after both radiographers have received formal training in interpretation of paediatric brain CT. (orig.)

  8. PET CT imaging: the Philippine experience

    International Nuclear Information System (INIS)

    Currently, the most discussed fusion imaging is PET CT. Fusion technology has tremendous potential in diagnostic imaging to detect numerous conditions such as tumors, Alzheimer's disease, dementia and neural disorders. The fusion of PET with CT helps in the localization of molecular abnormalities, thereby increasing diagnostic accuracy and differentiating benign or artefact lesions from malignant diseases. It uses a radiotracer called fluro deoxyglucose that gives a clear distinction between pathological and physiological uptake. Interest in this technology is increasing and additional clinical validation are likely to induce more health care providers to invest in combined scanners. It is hope that in time, a better appreciation of its advantages over conventional and traditional imaging modalities will be realized. The first PET CT facility in the country was established at the St. Luke's Medical Center in Quezon City in 2008 and has since then provided a state-of-the art imaging modality to its patients here and those from other countries. The paper will present the experiences so far gained from its operation, including the measures and steps currently taken by the facility to ensure optimum workers and patient safety. Plans and programs to further enhance the awareness of the Filipino public on this advanced imaging modality for an improved health care delivery system may also be discussed briefly. (author)

  9. Imaging of head and neck tumors -- methods: CT, spiral-CT, multislice-spiral-CT

    International Nuclear Information System (INIS)

    Spiral-CT is standard for imaging neck tumors. In correspondence with other groups we routinely use spiral-CT with thin slices (3 mm), a pitch of 1.3-1.5 and an overlapping reconstruction increment (2-3 mm). In patients with dental fillings a short additional spiral parallel to the corpus of the mandible reduces artifacts behind the dental arches and improves the diagnostic value of CT. For the assessment of the base of the skull, the orbital floor, the palate and paranasal sinuses an additional examination in the coronal plane is helpful. Secondary coronal reconstructions of axial scans are helpful in the evaluation of the crossing of the midline by small tumors of the tongue base or palate. For an optimal vascular or tissue contrast a sufficient volume of contrast medium and a start delay greater than 70-80 s are necessary. In our opinion the best results can be achieved with a volume of 150 ml, a flow of 2.5 ml/s and a start delay of 80 s. Dynamic enhanced CT is only necessary in some special cases. There is clear indication for dynamic enhanced CT where a glomus tumor is suspected. Additional functional CT imaging during i-phonation and/or Valsalva's maneuver are of great importance to prove vocal cords mobility. Therefore, imaging during i-phonation is an elemental part of every thorough examination of the hypopharynx and larynx region. Multislice-spiral-CT allows almost isotropic imaging of the head and neck region and improves the assessment of tumor spread and lymph node metastases in arbitrary oblique planes. Thin structures (the base of the skull, the orbital floor, the hard palate) as well as the floor of the mouth can be evaluated sufficiently with multiplanar reformations. Usually, additional coronal scanning is not necessary with multislice-spiral-CT. Multislice-spiral-CT is especially advantageous in defining the critical relationships of tumor and lymph node metastases and for functional imaging of the hypopharynx and larynx not only in the

  10. Imaging of head and neck tumors -- methods: CT, spiral-CT, multislice-spiral-CT

    Energy Technology Data Exchange (ETDEWEB)

    Baum, Ulrich E-mail: baum@idr.med.uni-erlangen.de; Greess, Holger; Lell, Michael; Noemayr, Anton; Lenz, Martin

    2000-03-01

    Spiral-CT is standard for imaging neck tumors. In correspondence with other groups we routinely use spiral-CT with thin slices (3 mm), a pitch of 1.3-1.5 and an overlapping reconstruction increment (2-3 mm). In patients with dental fillings a short additional spiral parallel to the corpus of the mandible reduces artifacts behind the dental arches and improves the diagnostic value of CT. For the assessment of the base of the skull, the orbital floor, the palate and paranasal sinuses an additional examination in the coronal plane is helpful. Secondary coronal reconstructions of axial scans are helpful in the evaluation of the crossing of the midline by small tumors of the tongue base or palate. For an optimal vascular or tissue contrast a sufficient volume of contrast medium and a start delay greater than 70-80 s are necessary. In our opinion the best results can be achieved with a volume of 150 ml, a flow of 2.5 ml/s and a start delay of 80 s. Dynamic enhanced CT is only necessary in some special cases. There is clear indication for dynamic enhanced CT where a glomus tumor is suspected. Additional functional CT imaging during i-phonation and/or Valsalva's maneuver are of great importance to prove vocal cords mobility. Therefore, imaging during i-phonation is an elemental part of every thorough examination of the hypopharynx and larynx region. Multislice-spiral-CT allows almost isotropic imaging of the head and neck region and improves the assessment of tumor spread and lymph node metastases in arbitrary oblique planes. Thin structures (the base of the skull, the orbital floor, the hard palate) as well as the floor of the mouth can be evaluated sufficiently with multiplanar reformations. Usually, additional coronal scanning is not necessary with multislice-spiral-CT. Multislice-spiral-CT is especially advantageous in defining the critical relationships of tumor and lymph node metastases and for functional imaging of the hypopharynx and larynx not only in the

  11. Evolving Concept of Small Vessel Disease through Advanced Brain Imaging.

    OpenAIRE

    Norrving, Bo

    2015-01-01

    Imaging plays a crucial role in studying and understanding cerebral small vessel disease. Several important findings have emerged from recent applications of advanced brain imaging methods. In patients with acute lacunar syndromes, diffusionweighted MRI studies have shown that the diagnostic precision of using clinical features alone or combined with CT scan findings to diagnose small vessel disease as the underlying cause is poor. Followup imaging studies on patients with acute infarcts rela...

  12. Comparison of adaptive statistical iterative and filtered back projection reconstruction techniques in brain CT

    International Nuclear Information System (INIS)

    Purpose: To compare image quality and visualization of normal structures and lesions in brain computed tomography (CT) with adaptive statistical iterative reconstruction (ASIR) and filtered back projection (FBP) reconstruction techniques in different X-ray tube current–time products. Materials and methods: In this IRB-approved prospective study, forty patients (nineteen men, twenty-one women; mean age 69.5 ± 11.2 years) received brain scan at different tube current–time products (300 and 200 mAs) in 64-section multi-detector CT (GE, Discovery CT750 HD). Images were reconstructed with FBP and four levels of ASIR-FBP blending. Two radiologists (please note that our hospital is renowned for its geriatric medicine department, and these two radiologists are more experienced in chronic cerebral vascular disease than in neoplastic disease, so this research did not contain cerebral tumors but as a discussion) assessed all the reconstructed images for visibility of normal structures, lesion conspicuity, image contrast and diagnostic confidence in a blinded and randomized manner. Volume CT dose index (CTDIvol) and dose-length product (DLP) were recorded. All the data were analyzed by using SPSS 13.0 statistical analysis software. Results: There was no statistically significant difference between the image qualities at 200 mAs with 50% ASIR blending technique and 300 mAs with FBP technique (p > .05). While between the image qualities at 200 mAs with FBP and 300 mAs with FBP technique a statistically significant difference (p < .05) was found. Conclusion: ASIR provided same image quality and diagnostic ability in brain imaging with greater than 30% dose reduction compared with FBP reconstruction technique

  13. Comparison of adaptive statistical iterative and filtered back projection reconstruction techniques in brain CT

    Energy Technology Data Exchange (ETDEWEB)

    Ren, Qingguo, E-mail: renqg83@163.com [Department of Radiology, Hua Dong Hospital of Fudan University, Shanghai 200040 (China); Dewan, Sheilesh Kumar, E-mail: sheilesh_d1@hotmail.com [Department of Geriatrics, Hua Dong Hospital of Fudan University, Shanghai 200040 (China); Li, Ming, E-mail: minli77@163.com [Department of Radiology, Hua Dong Hospital of Fudan University, Shanghai 200040 (China); Li, Jianying, E-mail: Jianying.Li@med.ge.com [CT Imaging Research Center, GE Healthcare China, Beijing (China); Mao, Dingbiao, E-mail: maodingbiao74@163.com [Department of Radiology, Hua Dong Hospital of Fudan University, Shanghai 200040 (China); Wang, Zhenglei, E-mail: Williswang_doc@yahoo.com.cn [Department of Radiology, Shanghai Electricity Hospital, Shanghai 200050 (China); Hua, Yanqing, E-mail: cjr.huayanqing@vip.163.com [Department of Radiology, Hua Dong Hospital of Fudan University, Shanghai 200040 (China)

    2012-10-15

    Purpose: To compare image quality and visualization of normal structures and lesions in brain computed tomography (CT) with adaptive statistical iterative reconstruction (ASIR) and filtered back projection (FBP) reconstruction techniques in different X-ray tube current–time products. Materials and methods: In this IRB-approved prospective study, forty patients (nineteen men, twenty-one women; mean age 69.5 ± 11.2 years) received brain scan at different tube current–time products (300 and 200 mAs) in 64-section multi-detector CT (GE, Discovery CT750 HD). Images were reconstructed with FBP and four levels of ASIR-FBP blending. Two radiologists (please note that our hospital is renowned for its geriatric medicine department, and these two radiologists are more experienced in chronic cerebral vascular disease than in neoplastic disease, so this research did not contain cerebral tumors but as a discussion) assessed all the reconstructed images for visibility of normal structures, lesion conspicuity, image contrast and diagnostic confidence in a blinded and randomized manner. Volume CT dose index (CTDI{sub vol}) and dose-length product (DLP) were recorded. All the data were analyzed by using SPSS 13.0 statistical analysis software. Results: There was no statistically significant difference between the image qualities at 200 mAs with 50% ASIR blending technique and 300 mAs with FBP technique (p > .05). While between the image qualities at 200 mAs with FBP and 300 mAs with FBP technique a statistically significant difference (p < .05) was found. Conclusion: ASIR provided same image quality and diagnostic ability in brain imaging with greater than 30% dose reduction compared with FBP reconstruction technique.

  14. RONI Based Secured and Authenticated Indexing of Lung CT Images

    OpenAIRE

    2015-01-01

    Medical images need to be transmitted with the patient's information without altering the image data. The present paper discusses secured indexing of lung CT image (SILI) which is a secured way of indexing the lung CT images with the patient information. Authentication is provided using the sender's logo information and the secret key is used for embedding the watermark into the host image. Watermark is embedded into the region of Noninterest (RONI) of the lung CT image. RONI is identified by...

  15. Denoising CT Images using wavelet transform

    Directory of Open Access Journals (Sweden)

    Lubna Gabralla

    2015-05-01

    Full Text Available Image denoising is one of the most significant tasks especially in medical image processing, where the original images are of poor quality due the noises and artifacts introduces by the acquisition systems. In this paper, we propose a new image denoising scheme by modifying the wavelet coefficients using soft-thresholding method, we present a comparative study of different wavelet denoising techniques for CT images and we discuss the obtained results. The denoising process rejects noise by thresholding in the wavelet domain. The performance is evaluated using Peak Signal-to-Noise Ratio (PSNR and Mean Squared Error (MSE. Finally, Gaussian filter provides better PSNR and lower MSE values. Hence, we conclude that this filter is an efficient one for preprocessing medical images.

  16. FDG PET/CT imaging in canine cancer patients

    DEFF Research Database (Denmark)

    Hansen, Anders Elias; McEvoy, Fintan; Engelholm, Svend Aage;

    2011-01-01

    and organs in canine cancer patients. FDG PET/CT was performed in 14 dogs including, nine mesenchymal tumors, four carcinomas, and one incompletely excised mast cell tumor. A generally higher FDG uptake was observed in carcinomas relative to sarcomas. Maximum SUV of carcinomas ranged from 7.6 to 27.......0, and for sarcomas from 2.0 to 10.6. The FDG SUV of several organs and tissues, including regional brain uptake is reported, to serve as a reference for future FDG PET studies in canine cancer patients. Several potential pitfalls have been recognized in interpretation of FDG PET images of human patients, a number...

  17. Correlations of CT and EEG findings in brain affections

    International Nuclear Information System (INIS)

    The results were compared of electroencephalography (EEG) and computerized tomography (CT) examinations of 250 patients with different brain affections. In intracranial expansive processes the pre-operative CT findings were positive in 100% cases, the EEG findings in 89.7% of cases. In severe traumatic affections the EEG and CT findings were positive in all cases, in mild injuries and post-traumatic conditions the EEG findings were more frequently positive than the CT. In focal and diffuse vascular affections the EEG and CT findings were consistent, in transitory ischemic conditions the EEG findings were more frequently positive. In inflammatory cerebral affections and in paroxymal diseases the EEG findings were positive more frequently than the CT. The same applies for demyelinating and degenerative affections. Findings of other authors were confirmed to the effect that CT very reliably reveals morphological changes in cerebral tissue while EEG records the functional state of the central nervous system and its changes. The two methods are complementary. (author)

  18. Brain image Compression, a brief survey

    Directory of Open Access Journals (Sweden)

    Saleha Masood

    2013-01-01

    Full Text Available Brain image compression is known as a subfield of image compression. It allows the deep analysis and measurements of brain images in different modes. Brain images are compressed to analyze and diagnose in an effective manner while reducing the image storage space. This survey study describes the different existing techniques regarding brain image compression. The techniques come under different categories. The study also discusses these categories.

  19. Computed tomographical imaging of the brain in post hypoglycemic coma

    Energy Technology Data Exchange (ETDEWEB)

    Iwai, A.; Sakamoto, T.; Kinoshita, Y.; Yokota, J.I.; Yoshioka, T.; Sugimoto, T.

    1987-07-01

    A case of post severe hypoglycemic coma was studied by sequential Computed Tomographic Imaging (CT) of the brain. The CT 1) was normal in the early stage, 2) subsequently showed a low density area, which was enhanced by the contrast medium, in the cerebral cortex and the boundary zone between the major cerebral arteries, and 3) revealed marked enhancement in the entire cortical region and hypodensity in the periventricular region in the late stage. These CT findings, representing the course of neural cell damage by severe hypoglycemia, are discussed from the pathophysiological viewpoint.

  20. Computed tomographical imaging of the brain in post hypoglycemic coma

    International Nuclear Information System (INIS)

    A case of post severe hypoglycemic coma was studied by sequential Computed Tomographic Imaging (CT) of the brain. The CT 1) was normal in the early stage, 2) subsequently showed a low density area, which was enhanced by the contrast medium, in the cerebral cortex and the boundary zone between the major cerebral arteries, and 3) revealed marked enhancement in the entire cortical region and hypodensity in the periventricular region in the late stage. These CT findings, representing the course of neural cell damage by severe hypoglycemia, are discussed from the pathophysiological viewpoint. (orig.)

  1. Evaluation of pulmonary emphysema by the fused image of CT image and ventilation SPECT image

    International Nuclear Information System (INIS)

    We evaluated pulmonary emphysema using a diagnostic device that could obtain a CT image, a ventilation single photon emission computed tomography (SPECT) image and a lung perfusion SPECT image in one examination. The fused image made from the CT image and SPECT image had very little position gap between images, and the precision was high. From the fused image, we were able to detect the areas in which emphysematous change was the most marked in the CT image, while the accumulation decrease was most remarkable in the ventilation SPECT image. Thus it was possible to obtain an accurate status of pulmonary emphysema, and our method was regarded as a useful technique. (author)

  2. The usefulness of brain MRI and CT in the clinical practice of epilepsia

    International Nuclear Information System (INIS)

    This study was conducted to clarify the usefulness of brain MRI and CT in the clinical practice of epilepsy. The subjects were 100 epileptic child patients (average age, 13.2±8.2 years) who underwent brain MRI, including 93 patients who also underwent brain CT. Twenty-two abnormal findings were obtained by MRI and 25 by CT. Thirty-nine patients who had complications such as mental retardation, cerebral palsy, or the overlapping disorders showed abnormal findings in a significantly high incidence. No significant correlations existed between the presence or absence of abnormal findings and the disease course after seizures. Patients with symptomatic localization-related epilepsies or cryptogenic and symptomatic generalized epilepsies showed abnormal findings in a significantly high incidence and unfavorable disease course after seizures. In 10 of 28 patients who showed abnormal findings, the abnormal finding site on images were correlated to the focus site on electroencephalograms. In conclusion, brain MRI and CT are essential in the clinical practice of epilepsy, however, we should notice the limitation of these methods. (Y.S.)

  3. Brain imaging in lung cancer patients without symptoms of brain metastases: a national survey of current practice in England

    International Nuclear Information System (INIS)

    Aim: To determine current practice regarding brain imaging for newly diagnosed lung cancer patients without symptoms of brain metastases. Materials and methods: A survey questionnaire was sent by e-mail to all the lung cancer lead clinicians in England currently on the National Cancer Intelligence Network database. The survey asked whether brain imaging was used in new lung cancer patients without symptoms or signs to suggest brain metastases; and if so, which patient subgroups were imaged according to cell type, stage of disease, and intention to treat, and which techniques were used to image these patients. Responses were received between February and May 2014. Results: Fifty-nine of 154 centres replied to the survey (38%). Thirty of the 59 centres (51%) did not image the brain in these patients. Twenty-nine of the 59 (49%) centres imaged the brain in at least certain subgroups. Of those centres that did image the brain 21 (72%) used CT as the first-line imaging technique and six (20%) used MRI. Twenty-five of 59 (42%) centres stated that the 2011 NICE guidelines had led to a change in their practice. Conclusion: There is wide variation in practice regarding brain imaging in this patient group in England, with no brain imaging at all in approximately half of centres and a spectrum of imaging in the other half. When the brain is imaged, CT is the technique most commonly used. The 2011 NICE guidelines have led to some change in practice but not to national uniformity. - Highlights: • Ascertain current practice in brain imaging for staging asymptomatic lung cancer patients. • Survey questionnaire sent to all the lung cancer lead clinicians in England. • Wide variation in practice with regard to brain imaging in this patient group. • No brain imaging at all in approximately half of centres and a spectrum of imaging in the other half • The 2011 NICE guidelines have led to some change in practice but not to national uniformity

  4. In vivo imaging of MSCT and Micro-CT. A comparison

    International Nuclear Information System (INIS)

    Purpose: To evaluate the potential of MSCT and a novel μCT system to assess the volume of malignant brain tumors in rats compared to histology. Materials and Methods: Fourteen rats underwent stereotactic implantation of GFP-marked F 98-glioma cells. On day 10 after implantation, animals received double-dose contrast-enhanced μCT and MSCT imaging using Iomeprol. MSCT- and μCT-derived tumor volumes were calculated and compared to histology (fluorescence staining) as the gold standard. Results: There was good correlation between the μCT-derived tumor volume (69 ± 23 mm3) and histology (81 ± 14 mm3; p > 0.14). MSCT, however, showed significantly smaller tumor volumes (55 ± 25 mm3) compared to histology (p < 0.01) but was able to detect the tumors in all animals. Conclusion: μCT allows in vivo imaging of the contrast-enhancing parts of experimental gliomas with high correlation to histology. Although MSCT is less suitable for assessing exact tumor volume, this method reliably detects tumors in rats. Due to the high spatial resolution, μCT-systems could play an important role for fusion imaging, e.g. to assess experimental brain gliomas with multimodal μCT/PET- or μCT/MRI-fusion images.

  5. CT Imaging for Gynecological HDR: Tools and Tricks

    International Nuclear Information System (INIS)

    Computerized tomography (CT)-assisted treatment planning for high-dose-rate (HDR) gynecological cancer treatments allows for better structure visualization and dose-volume histogram analysis definition. Problems associated with CT imaging are addressed. These pitfalls include the potential for multiple patient transfers and movement between applicator insertion, simulation, and treatment. Applicator CT imaging artifacts are also discussed. A modified transport table and a machined connection for a commercially available non-CT-compatible tandem and a CT-compatible ring applicator are described. These 2 modifications provide a safe and reliable method to utilize the advantages of CT imaging for gynecological HDR treatments

  6. The value of brain CT findings in acute methanol toxicity

    Energy Technology Data Exchange (ETDEWEB)

    Taheri, Morteza Sanei [Department of Radiology, Shohada Hospital, Shahid Beheshti University of Medical Sciences, Tehran (Iran, Islamic Republic of); Poison Control Center, Loghman-Hakim Poison Hospital, Shahid Beheshti University of Medical Sciences, Tehran (Iran, Islamic Republic of)], E-mail: saneim@yahoo.com; Moghaddam, Hossein Hassanian [Poison Control Center, Loghman-Hakim Poison Hospital, Shahid Beheshti University of Medical Sciences, Tehran (Iran, Islamic Republic of); Moharamzad, Yashar; Dadgari, Shahrzad [Department of Radiology, Shohada Hospital, Shahid Beheshti University of Medical Sciences, Tehran (Iran, Islamic Republic of); Nahvi, Vahideh [Poison Control Center, Loghman-Hakim Poison Hospital, Shahid Beheshti University of Medical Sciences, Tehran (Iran, Islamic Republic of)

    2010-02-15

    Objective: Due to depressant effects of methanol on the central nervous system, brain computed tomography (CT) scan has been introduced as a diagnostic device in methanol intoxication. The authors aimed to present brain CT findings in patients with acute methanol intoxication and to determine signs associated with death. Materials and methods: This cohort study involved 42 consecutive patients with acute methanol intoxication. Inclusion criteria were consisted of characteristic clinical presentation of methanol poisoning, and metabolic acidosis with increased anion and osmolar gaps. Brain CT scans without contrast medium were obtained. To determine the association between the CT findings and death, the chi-square test or the Fisher's exact test, odds ratio (OR) and its 95% confidence interval (95% CI) were calculated. Results: Twenty-eight patients (66.6%) had a total of 55 abnormal findings on brain CT, in which bilateral putaminal hypodense lesions was the most common manifestation (27 cases, 96.4%). Putaminal hemorrhage with varying degrees was observed in 7 patients (25%). Six patients (21.4%) had low attenuation lesions in the subcortical white matter of the insula. A significant association was observed between putaminal hemorrhage (OR = 8, 95% CI = 1.187-53.93, P = 0.018) and subcortical necrosis of the insula (OR = 11, 95% CI = 1.504-80.426, P = 0.007) with death. Conclusion: In addition to clinical and laboratory findings, presence of putaminal hemorrhage and insular subcortex white matter necrosis are associated with a poor clinical outcome in patients with methanol poisoning.

  7. REGISTRATION OF BRAIN IMAGES USING MODIFIED ADAPTIVE POLAR TRANSFORM

    Directory of Open Access Journals (Sweden)

    D.Sasikala,

    2010-09-01

    Full Text Available Image registration has great significance in medicine, with a lot of techniques anticipated in it. This paper discusses an approach for medical image registration. It registers images of the mono or multi modalities for CT or MRI images using Modified Adaptive Polar Transform. The performance of the Adaptive Polar Transform with theproposed technique is examined. The results prove that the proposed method performs better than Adaptive Polar Transform technique. The proposed method reduces the errors and also the elapsed time for registration. An analysis is presented for the medical image registration of brain images using Adaptive Polar Transform and Modified Adaptive Polar Transform.

  8. Body-wide anatomy recognition in PET/CT images

    Science.gov (United States)

    Wang, Huiqian; Udupa, Jayaram K.; Odhner, Dewey; Tong, Yubing; Zhao, Liming; Torigian, Drew A.

    2015-03-01

    With the rapid growth of positron emission tomography/computed tomography (PET/CT)-based medical applications, body-wide anatomy recognition on whole-body PET/CT images becomes crucial for quantifying body-wide disease burden. This, however, is a challenging problem and seldom studied due to unclear anatomy reference frame and low spatial resolution of PET images as well as low contrast and spatial resolution of the associated low-dose CT images. We previously developed an automatic anatomy recognition (AAR) system [15] whose applicability was demonstrated on diagnostic computed tomography (CT) and magnetic resonance (MR) images in different body regions on 35 objects. The aim of the present work is to investigate strategies for adapting the previous AAR system to low-dose CT and PET images toward automated body-wide disease quantification. Our adaptation of the previous AAR methodology to PET/CT images in this paper focuses on 16 objects in three body regions - thorax, abdomen, and pelvis - and consists of the following steps: collecting whole-body PET/CT images from existing patient image databases, delineating all objects in these images, modifying the previous hierarchical models built from diagnostic CT images to account for differences in appearance in low-dose CT and PET images, automatically locating objects in these images following object hierarchy, and evaluating performance. Our preliminary evaluations indicate that the performance of the AAR approach on low-dose CT images achieves object localization accuracy within about 2 voxels, which is comparable to the accuracies achieved on diagnostic contrast-enhanced CT images. Object recognition on low-dose CT images from PET/CT examinations without requiring diagnostic contrast-enhanced CT seems feasible.

  9. The pros and cons of intraoperative CT scan in evaluation of deep brain stimulation lead implantation: A retrospective study

    Science.gov (United States)

    Servello, Domenico; Zekaj, Edvin; Saleh, Christian; Pacchetti, Claudio; Porta, Mauro

    2016-01-01

    Background: Deep brain stimulation (DBS) is an established therapy for movement disorders, such as Parkinson's disease (PD), dystonia, and tremor. The efficacy of DBS depends on the correct lead positioning. The commonly adopted postoperative radiological evaluation is performed with computed tomography (CT) scan and/or magnetic resonance imaging (MRI). Methods: We conducted a retrospective study on 202 patients who underwent DBS from January 2009 to October 2013. DBS indications were PD, progressive supranuclear palsy, tremor, dystonia, Tourette syndrome, obsessive compulsive disorder, depression, and Huntington's disease. Preoperatively, all patients underwent brain MRI and brain CT scan with the stereotactic frame positioned. The lead location was confirmed intraoperatively with CT. The CT images were subsequently transferred to the Stealth Station Medtronic and merged with the preoperative planning. On the first or second day after, implantation we performed a brain MRI to confirm the correct position of the lead. Results: In 14 patients, leads were in suboptimal position after intraoperative CT scan positioning. The cases with alteration in the Z-axis were corrected immediately under fluoroscopic guidance. In all the 14 patients, an immediate repositioning was done. Conclusions: Based on our data, intraoperative CT scan is fast, safe, and a useful tool in the evaluation of the position of the implanted lead. It also reduces the patient's discomfort derived from the transfer of the patient from the operating room to the radiological department. However, intraoperative CT should not be considered as a substitute for postoperative MRI.

  10. Functional Brain Imaging: A Comprehensive Survey

    CERN Document Server

    Sarraf, Saman

    2016-01-01

    Functional brain imaging allows measuring dynamic functionality in all brain regions. It is broadly used in clinical cognitive neuroscience as, well as in research. It will allow the observation of neural activities in the brain simultaneously. From the beginning when functional brain imaging was initiated by the mapping of brain functions proposed by phrenologists, many scientists were asking why we need to image brain functionality since we have already structural information. Simply, their important question was including a great answer. Functional information of the human brain would definitely complement structural information, helping to have a better understanding of what is happening in the brain. This paper, which could be useful to those who have an interest in functional brain imaging, such as engineers, will present a quick review of modalities used in functional brain imaging. We will concentrate on the most used techniques in functional imaging which are functional magnetic resonance imaging (fM...

  11. CT-guided laser probe for ablation of brain tumors

    Directory of Open Access Journals (Sweden)

    Abdolhadi Daneshi

    2010-01-01

    Full Text Available   Abstract  In this study, 22 patients (15-75 years old were selected and transferred to CT scan for tumor ablation. For ablations, after prep and drep under the local anesthesia and mild sedation in proper position, small incision made and special needle inserted and guided by proper direction to the core of the tumor. Then, laser probe inserted through the needle and laser energy delivered. Although we have not a good prognosis in metastatic tumors but post-operative follow up and brain CT scan established the effect of laser on resection and evaporation and diminution of mass effect in tumor lesions.

  12. Attenuation correction of emission PET images with average CT: Interpolation from breath-hold CT

    International Nuclear Information System (INIS)

    Misregistration resulting from the difference of temporal resolution in PET and CT scans occur frequently in PET/CT imaging, which causes distortion in tumor quantification in PET. Respiration cine average CT (CACT) for PET attenuation correction has been reported to improve the misalignment effectively by several papers. However, the radiation dose to the patient from a four-dimensional CT scan is relatively high. In this study, we propose a method to interpolate respiratory CT images over a respiratory cycle from inhalation and exhalation breath-hold CT images, and use the average CT from the generated CT set for PET attenuation correction. The radiation dose to the patient is reduced using this method. Six cancer patients of various lesion sites underwent routine free-breath helical CT (HCT), respiration CACT, interpolated average CT (IACT), and 18F-FDG PET. Deformable image registration was used to interpolate the middle phases of a respiratory cycle based on the end-inspiration and end-expiration breath-hold CT scans. The average CT image was calculated from the eight interpolated CT image sets of middle respiratory phases and the two original inspiration and expiration CT images. Then the PET images were reconstructed by these three methods for attenuation correction using HCT, CACT, and IACT. Misalignment of PET image using either CACT or IACT for attenuation correction in PET/CT was improved. The difference in standard uptake value (SUV) from tumor in PET images was most significant between the use of HCT and CACT, while the least significant between the use of CACT and IACT. Besides the similar improvement in tumor quantification compared to the use of CACT, using IACT for PET attenuation correction reduces the radiation dose to the patient.

  13. Attenuation correction of emission PET images with average CT: Interpolation from breath-hold CT

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Tzung-Chi [Department of Biomedical Imaging and Radiological Science, China Medical University, Taiwan (China); Zhang, Geoffrey [Department of Radiation Oncology, Moffitt Cancer Center, FL (United States); Chen, Chih-Hao [Department of Nuclear Medicine, Taipei Veterans General Hospital, Taiwan (China); Yang, Bang-Hung [Department of Nuclear Medicine, Taipei Veterans General Hospital, Taiwan (China); Department of Biomedical Imaging and Radiological Sciences, National Yang Ming University, Taiwan (China); Wu, Nien-Yun [Department of Nuclear Medicine, Taipei Veterans General Hospital, Taiwan (China); Wang, Shyh-Jen, E-mail: jwshyh@vghtpe.gov.tw [Department of Nuclear Medicine, Taipei Veterans General Hospital, Taiwan (China); Department of Biomedical Imaging and Radiological Sciences, National Yang Ming University, Taiwan (China); Wu, Tung-Hsin, E-mail: tung@ym.edu.tw [Department of Biomedical Imaging and Radiological Sciences, National Yang Ming University, Taiwan (China)

    2011-05-15

    Misregistration resulting from the difference of temporal resolution in PET and CT scans occur frequently in PET/CT imaging, which causes distortion in tumor quantification in PET. Respiration cine average CT (CACT) for PET attenuation correction has been reported to improve the misalignment effectively by several papers. However, the radiation dose to the patient from a four-dimensional CT scan is relatively high. In this study, we propose a method to interpolate respiratory CT images over a respiratory cycle from inhalation and exhalation breath-hold CT images, and use the average CT from the generated CT set for PET attenuation correction. The radiation dose to the patient is reduced using this method. Six cancer patients of various lesion sites underwent routine free-breath helical CT (HCT), respiration CACT, interpolated average CT (IACT), and 18F-FDG PET. Deformable image registration was used to interpolate the middle phases of a respiratory cycle based on the end-inspiration and end-expiration breath-hold CT scans. The average CT image was calculated from the eight interpolated CT image sets of middle respiratory phases and the two original inspiration and expiration CT images. Then the PET images were reconstructed by these three methods for attenuation correction using HCT, CACT, and IACT. Misalignment of PET image using either CACT or IACT for attenuation correction in PET/CT was improved. The difference in standard uptake value (SUV) from tumor in PET images was most significant between the use of HCT and CACT, while the least significant between the use of CACT and IACT. Besides the similar improvement in tumor quantification compared to the use of CACT, using IACT for PET attenuation correction reduces the radiation dose to the patient.

  14. Attenuation correction of emission PET images with average CT: Interpolation from breath-hold CT

    Science.gov (United States)

    Huang, Tzung-Chi; Zhang, Geoffrey; Chen, Chih-Hao; Yang, Bang-Hung; Wu, Nien-Yun; Wang, Shyh-Jen; Wu, Tung-Hsin

    2011-05-01

    Misregistration resulting from the difference of temporal resolution in PET and CT scans occur frequently in PET/CT imaging, which causes distortion in tumor quantification in PET. Respiration cine average CT (CACT) for PET attenuation correction has been reported to improve the misalignment effectively by several papers. However, the radiation dose to the patient from a four-dimensional CT scan is relatively high. In this study, we propose a method to interpolate respiratory CT images over a respiratory cycle from inhalation and exhalation breath-hold CT images, and use the average CT from the generated CT set for PET attenuation correction. The radiation dose to the patient is reduced using this method. Six cancer patients of various lesion sites underwent routine free-breath helical CT (HCT), respiration CACT, interpolated average CT (IACT), and 18F-FDG PET. Deformable image registration was used to interpolate the middle phases of a respiratory cycle based on the end-inspiration and end-expiration breath-hold CT scans. The average CT image was calculated from the eight interpolated CT image sets of middle respiratory phases and the two original inspiration and expiration CT images. Then the PET images were reconstructed by these three methods for attenuation correction using HCT, CACT, and IACT. Misalignment of PET image using either CACT or IACT for attenuation correction in PET/CT was improved. The difference in standard uptake value (SUV) from tumor in PET images was most significant between the use of HCT and CACT, while the least significant between the use of CACT and IACT. Besides the similar improvement in tumor quantification compared to the use of CACT, using IACT for PET attenuation correction reduces the radiation dose to the patient.

  15. Source position error influence on industry CT image quality

    International Nuclear Information System (INIS)

    Based on the emulational exercise, the influence of source position error on industry CT (ICT) image quality was studied and the valuable parameters were obtained for the design of ICT. The vivid container CT image was also acquired from the CT testing system. (authors)

  16. Imaging the Addicted Human Brain

    OpenAIRE

    Fowler, Joanna S.; Volkow, Nora D.; Kassed, Cheryl A; Chang, Linda

    2007-01-01

    Modern imaging techniques enable researchers to observe drug actions and consequences as they occur and persist in the brains of abusing and addicted individuals. This article presents the five most commonly used techniques, explains how each produces images, and describes how researchers interpret them. The authors give examples of key findings illustrating how each technique has extended and deepened our knowledge of the neurobiological bases of drug abuse and addiction, and they address po...

  17. Minireview of Stereoselective Brain Imaging

    DEFF Research Database (Denmark)

    Smith, Donald F.; Jakobsen, Steen

    2014-01-01

    Stereoselectivity is a fundamental principle in living systems. Stereoselectivity reflects the dependence of molecular processes on the spatial orientation of constituent atoms. Stereoselective processes govern many aspects of brain function and direct the course of many psychotropic drugs. Today......, modern imaging techniques such as SPECT and PET provide a means for studying stereoselective processes in the living brain. Chemists have prepared numerous radiolabelled stereoisomers for use in SPECT and PET in order to explore various molecular processes in the living brain of anesthetized laboratory...... animals and awake humans. The studies have demonstrated how many aspects of neurotransmission consist of crucial stereoselective events that can affect brain function in health and disease. Here, we present a brief account of those findings in hope of stimulating further interest in the vital topic....

  18. Image reconstruction design of industrial CT instrument for teaching

    International Nuclear Information System (INIS)

    Industrial CT instrument for teaching is applied to teaching and study in field of physics and radiology major, image reconstruction is an important part of software on CT instrument. The paper expatiate on CT physical theory and first generation CT reconstruction algorithm, describe scan process of industrial CT instrument for teaching; analyze image artifact as result of displacement of rotation center, implement method of center displacement correcting, design and complete image reconstruction software, application shows that reconstructed image is very clear and qualitatively high. (authors)

  19. Research on Perfusion CT in Rabbit Brain Tumor Model

    International Nuclear Information System (INIS)

    We investigated the vascular characteristics of tumors and normal tissue using perfusion CT in the rabbit brain tumor model. The VX2 carcinoma concentration of 1 x 107 cells/ml(0.1 ml) was implanted in the brain of nine New Zealand white rabbits (weight: 2.4 kg-3.0 kg, mean: 2.6 kg). The perfusion CT was scanned when the tumors were grown up to 5 mm. The tumor volume and perfusion value were quantitatively analyzed by using commercial workstation (advantage windows workstation, AW, version 4.2, GE, USA). The mean volume of implanted tumors was 316±181 mm3, and the biggest and smallest volumes of tumor were 497 mm3 and 195 mm3, respectively. All the implanted tumors in rabbits are single-nodular tumors, and intracranial metastasis was not observed. In the perfusion CT, cerebral blood volume (CBV) were 74.40±9.63, 16.8±0.64, 15.24±3.23 ml/100g in the tumor core, ipsilateral normal brain, and contralateral normal brain, respectively (p≤0.05). In the cerebral blood flow (CBF), there were significant differences between the tumor core and both normal brains (p≤0.05), but no significant differences between ipsilateral and contralateral normal brains (962.91±75.96 vs. 357.82±12.82 vs. 323.19±83.24 ml/100g/min). In the mean transit time (MTT), there were significant differences between the tumor core and both normal brains (p≤0.05), but no significant differences between ipsilateral and contralateral normal brains (4.37±0.19 vs. 3.02±0.41 vs. 2.86±0.22 sec). In the permeability surface (PS), there were significant differences among the tumor core, ipsilateral and contralateral normal brains (47.23±25.44 vs. 14.54±1.60 vs. 6.81±4.20 ml/100g/min)(p≤0.05). In the time to peak (TTP) were no significant differences among the tumor core, ipsilateral and contralateral normal brains. In the positive enhancement integral (PEI), there were significant differences among the tumor core, ipsilateral and contralateral brains (61.56±16.07 vs. 12.58±2.61 vs. 8.26±5

  20. Research on Perfusion CT in Rabbit Brain Tumor Model

    Energy Technology Data Exchange (ETDEWEB)

    Ha, Bon Chul; Kwak, Byung Kook; Jung, Ji Sung [Dept. of Diagnostic Radiology, Chung Ang University Hospital, Seoul (Korea, Republic of); Lim, Cheong Hwan; Jung, Hong Ryang [Dept. of Radiological Science, Hanseo University, Seosan (Korea, Republic of)

    2012-06-15

    We investigated the vascular characteristics of tumors and normal tissue using perfusion CT in the rabbit brain tumor model. The VX2 carcinoma concentration of 1 x 10{sup 7} cells/ml(0.1 ml) was implanted in the brain of nine New Zealand white rabbits (weight: 2.4 kg-3.0 kg, mean: 2.6 kg). The perfusion CT was scanned when the tumors were grown up to 5 mm. The tumor volume and perfusion value were quantitatively analyzed by using commercial workstation (advantage windows workstation, AW, version 4.2, GE, USA). The mean volume of implanted tumors was 316{+-}181 mm{sup 3}, and the biggest and smallest volumes of tumor were 497 mm{sup 3} and 195 mm{sup 3}, respectively. All the implanted tumors in rabbits are single-nodular tumors, and intracranial metastasis was not observed. In the perfusion CT, cerebral blood volume (CBV) were 74.40{+-}9.63, 16.8{+-}0.64, 15.24{+-}3.23 ml/100g in the tumor core, ipsilateral normal brain, and contralateral normal brain, respectively (p{<=}0.05). In the cerebral blood flow (CBF), there were significant differences between the tumor core and both normal brains (p{<=}0.05), but no significant differences between ipsilateral and contralateral normal brains (962.91{+-}75.96 vs. 357.82{+-}12.82 vs. 323.19{+-}83.24 ml/100g/min). In the mean transit time (MTT), there were significant differences between the tumor core and both normal brains (p{<=}0.05), but no significant differences between ipsilateral and contralateral normal brains (4.37{+-}0.19 vs. 3.02{+-}0.41 vs. 2.86{+-}0.22 sec). In the permeability surface (PS), there were significant differences among the tumor core, ipsilateral and contralateral normal brains (47.23{+-}25.44 vs. 14.54{+-}1.60 vs. 6.81{+-}4.20 ml/100g/min)(p{<=}0.05). In the time to peak (TTP) were no significant differences among the tumor core, ipsilateral and contralateral normal brains. In the positive enhancement integral (PEI), there were significant differences among the tumor core, ipsilateral and

  1. CT findings of the brain post cardiopulmonary resuscitation

    International Nuclear Information System (INIS)

    The subjects were 88 cases of non-traumatic CPA excluding those with primary brain disease. The subjects were divided into 4 groups according to the duration of cardiac arrest: Group A (less than 15 minutes, 2 cases), Group B (15-30 minutes, 11 cases), Group C (more than 30 minutes, 40 cases), Group D (no resuscitation after cardiac arrest, 35 cases). All cases in Group A were observed to be clear consciousness after resuscitation. Not only the functional outcome but also the survivals rates were poorer as the duration of cardiac arrest increased in Groups B and C compared to Group A. The mortality rate was 85% or higher for cardiac arrest of 15 minutes or longer. Brain edema after resuscitation was examined by head CT in the basal-ganglia and thalamus regions, and in the corticomedullary junction of the cerebrum. In the cases of short duration of cardiac arrest, the basal-ganglia and thalamus regions, and the corticomedullary junction were clearly visible on CT. On the other hand, these areas were poorly or not visible (marked brain edema) in the cases of longer duration of cardiac arrest. The borders of the basal-ganglia and thalamus regions, and the corticomedullary junction were not obscured in any of the cases in Group A. However, the borders of these regions were poorly visible or not visible more frequently as the duration of cardiac arrest increased. In particular, the corticomedullary junction was not visible more frequently after cardiac arrest of long duration. Brain edema is caused and intensified by prolongation of hypoxia, but it is also reported to be caused by external cardiac massage, which increases the intracranial pressure. This was also suggested by the more notable brain edema in the corticomedullary junction than in the basal-ganglia and thalamus regions. These findings of brain edema appeared on head CT within 4 hours after CPR. Findings suggestive of vascular occlusion were also obtained. (K.H.)

  2. 3D Interpolation Method for CT Images of the Lung

    Directory of Open Access Journals (Sweden)

    Noriaki Asada

    2003-06-01

    Full Text Available A 3-D image can be reconstructed from numerous CT images of the lung. The procedure reconstructs a solid from multiple cross section images, which are collected during pulsation of the heart. Thus the motion of the heart is a special factor that must be taken into consideration during reconstruction. The lung exhibits a repeating transformation synchronized to the beating of the heart as an elastic body. There are discontinuities among neighboring CT images due to the beating of the heart, if no special techniques are used in taking CT images. The 3-D heart image is reconstructed from numerous CT images in which both the heart and the lung are taken. Although the outline shape of the reconstructed 3-D heart is quite unnatural, the envelope of the 3-D unnatural heart is fit to the shape of the standard heart. The envelopes of the lung in the CT images are calculated after the section images of the best fitting standard heart are located at the same positions of the CT images. Thus the CT images are geometrically transformed to the optimal CT images fitting best to the standard heart. Since correct transformation of images is required, an Area oriented interpolation method proposed by us is used for interpolation of transformed images. An attempt to reconstruct a 3-D lung image by a series of such operations without discontinuity is shown. Additionally, the same geometrical transformation method to the original projection images is proposed as a more advanced method.

  3. Microcomputer-based image processing system for CT/MRI scans II

    International Nuclear Information System (INIS)

    This paper reports that a microcomputer-based image processing system is used to digitize and process serial sections of CT/MRI scan and reconstruct three-dimensional images of brain structures and brain lesions. The images grabbed also serve as templates and different vital regions with different risk values are also traced out for 3D reconstruction. A knowledge-based system employing rule-based programming has been built to help identifying brain lesions and to help planning trajectory for operations. The volumes of the lesions are also automatically determined. Such system is very useful for medical skills archival, tumor size monitoring, survival and outcome forecasting, and consistent neurosurgical planning

  4. Pathologic CT findings of the brain in infancy and childhood

    International Nuclear Information System (INIS)

    The results of 152 CT brain scans in infant and children are reported. Selected cases are demonstrated with special respect to tumors, malformation, dysplasias of the cerebral vasculature, and acquired lesions. A comparative study of alterations seen in the electroencephalogram to morphologic changes in the computer tomogram showed that unspecific EEG alterations are mainly seen in tumors, subdural and epidural effusions, and lesions with ventricular enlargement, whereas hypersynchronous alterations were mostly found in children with substantial brain defects and cystic encephalopathy. (orig.) 891 MG/orig. 892 MB

  5. Whole brain CT perfusion in acute anterior circulation ischemia: coverage size matters

    International Nuclear Information System (INIS)

    Our aim was to compare infarct core volume on whole brain CT perfusion (CTP) with several limited coverage sizes (i.e., 3, 4, 6, and 8 cm), as currently used in routine clinical practice. In total, 40 acute ischemic stroke patients with non-contrast CT (NCCT) and CTP imaging of anterior circulation ischemia were included. Imaging was performed using a 320-multislice CT. Average volumes of infarct core of all simulated partial coverage sizes were calculated. Infarct core volume of each partial brain coverage was compared with infarct core volume of whole brain coverage and expressed using a percentage. To determine the optimal starting position for each simulated CTP coverage, the percentage of infarct coverage was calculated for every possible starting position of the simulated partial coverage in relation to Alberta Stroke Program Early CT Score in Acute Stroke Triage (ASPECTS 1) level. Whole brain CTP coverage further increased the percentage of infarct core volume depicted by 10 % as compared to the 8-cm coverage when the bottom slice was positioned at the ASPECTS 1 level. Optimization of the position of the region of interest (ROI) in 3 cm, 4 cm, and 8 cm improved the percentage of infarct depicted by 4 % for the 8-cm, 7 % for the 4-cm, and 13 % for the 3-cm coverage size. This study shows that whole brain CTP is the optimal coverage for CTP with a substantial improvement in accuracy in quantifying infarct core size. In addition, our results suggest that the optimal position of the ROI in limited coverage depends on the size of the coverage. (orig.)

  6. Whole brain CT perfusion in acute anterior circulation ischemia: coverage size matters

    Energy Technology Data Exchange (ETDEWEB)

    Emmer, B.J. [Erasmus Medical Centre, Department of Radiology, Postbus 2040, Rotterdam (Netherlands); Rijkee, M.; Walderveen, M.A.A. van [Leiden University Medical Centre, Department of Radiology, Leiden (Netherlands); Niesten, J.M.; Velthuis, B.K. [University Medical Centre Utrecht, Department of Radiology, Utrecht (Netherlands); Wermer, M.J.H. [Leiden University Medical Centre, Department of Neurology, Leiden (Netherlands)

    2014-12-15

    Our aim was to compare infarct core volume on whole brain CT perfusion (CTP) with several limited coverage sizes (i.e., 3, 4, 6, and 8 cm), as currently used in routine clinical practice. In total, 40 acute ischemic stroke patients with non-contrast CT (NCCT) and CTP imaging of anterior circulation ischemia were included. Imaging was performed using a 320-multislice CT. Average volumes of infarct core of all simulated partial coverage sizes were calculated. Infarct core volume of each partial brain coverage was compared with infarct core volume of whole brain coverage and expressed using a percentage. To determine the optimal starting position for each simulated CTP coverage, the percentage of infarct coverage was calculated for every possible starting position of the simulated partial coverage in relation to Alberta Stroke Program Early CT Score in Acute Stroke Triage (ASPECTS 1) level. Whole brain CTP coverage further increased the percentage of infarct core volume depicted by 10 % as compared to the 8-cm coverage when the bottom slice was positioned at the ASPECTS 1 level. Optimization of the position of the region of interest (ROI) in 3 cm, 4 cm, and 8 cm improved the percentage of infarct depicted by 4 % for the 8-cm, 7 % for the 4-cm, and 13 % for the 3-cm coverage size. This study shows that whole brain CTP is the optimal coverage for CTP with a substantial improvement in accuracy in quantifying infarct core size. In addition, our results suggest that the optimal position of the ROI in limited coverage depends on the size of the coverage. (orig.)

  7. Biochemical imaging of the human brain in development and disease

    International Nuclear Information System (INIS)

    The authors used positron emission tomography (PET) to image cerebral glucose metabolism in more than 140 children aged 5 days to 15 years. Twenty-nine children were studied during normal development and the remainder because of infantile spasm, seizure, Lennox-Gastaut syndrome, or cerebral palsy. This exhibit demonstrates the temporal course of normal function (metabolic) development of the brain, and compares the relative value of PET, MR imaging, and x-ray CT in abnormal cases

  8. Diffuse Optical Tomography for Brain Imaging: Theory

    Science.gov (United States)

    Yuan, Zhen; Jiang, Huabei

    Diffuse optical tomography (DOT) is a noninvasive, nonionizing, and inexpensive imaging technique that uses near-infrared light to probe tissue optical properties. Regional variations in oxy- and deoxy-hemoglobin concentrations as well as blood flow and oxygen consumption can be imaged by monitoring spatiotemporal variations in the absorption spectra. For brain imaging, this provides DOT unique abilities to directly measure the hemodynamic, metabolic, and neuronal responses to cells (neurons), and tissue and organ activations with high temporal resolution and good tissue penetration. DOT can be used as a stand-alone modality or can be integrated with other imaging modalities such as fMRI/MRI, PET/CT, and EEG/MEG in studying neurophysiology and pathology. This book chapter serves as an introduction to the basic theory and principles of DOT for neuroimaging. It covers the major aspects of advances in neural optical imaging including mathematics, physics, chemistry, reconstruction algorithm, instrumentation, image-guided spectroscopy, neurovascular and neurometabolic coupling, and clinical applications.

  9. Multidimensional MRI-CT atlas of the naked mole-rat brain

    Directory of Open Access Journals (Sweden)

    Fumiko Seki

    2013-12-01

    Full Text Available Naked mole-rats have a variety of distinctive features such as the organisation of a hierarchical society (known as eusociality, extraordinary longevity, and cancer resistance; thus, it would be worthwhile investigating these animals in detail. One important task is the preparation of a brain atlas database that provide comprehensive information containing multidimensional data with various image contrasts, which can be achievable using a magnetic resonance imaging (MRI. Advanced MRI techniques such as diffusion tensor imaging (DTI, which generates high contrast images of fibre structures, can characterise unique morphological properties in addition to conventional MRI. To obtain high spatial resolution images, MR histology, DTI, and X-ray computed tomography (CT were performed on the fixed adult brain. Skull and brain structures were segmented as well as reconstructed in stereotaxic coordinates. Data were also acquired for the neonatal brain to allow developmental changes to be observed. Moreover, in vivo imaging of naked mole-rats was established as an evaluation tool of live animals. The data obtained comprised three-dimensional (3D images with high tissue contrast as well as stereotaxic coordinates. Developmental differences in the visual system were highlighted in particular by DTI. Although it was difficult to delineate optic nerves in the mature adult brain, parts of them could be distinguished in the immature neonatal brain. From observation of cortical thickness, possibility of high somatosensory system development replaced to the visual system was indicated. 3D visualisation of brain structures in the atlas as well as the establishment of in vivo imaging would promote neuroimaging researches towards detection of novel characteristics of eusocial naked mole-rats.

  10. Dynamic CT and functional imaging with intracranial tumors

    International Nuclear Information System (INIS)

    Eleven cases with verified intracranial meningioma were examined by means of dynamic computed tomography using a GE CT/T 8800 scanner equipped with a special software program. The first scan of the dynamic CT was started simultaneously with the start of an intravenous injection of an iodinated contrast medium. Serial 4.8-sec. scans were repeated 6 times, the data for each scan were segmented into 2, and a series of 12 rapid-sequence scan images was generated. The time-density data were analyzed with multiple ROIs, and the flow parameters, such as the peak height (P), the area (A), the time-to-peak (TP), the first moment (M1), and the effective width (EW = A/P), were calculated. In addition, each parameter was reorganized, pixel by pixel, as a functional image for observation and storage. M1, A, and P were increased in the tumor, whereas P and A were low and M1 was high in the peritumoral edema. In cases where the tumor was associated with a marked edema and/or a shift of the midline structures, the flow through the contralateral hemisphere was also compromised. A disturbed blood flow through the peritumoral region as well as contralateral brain showed an improvement after the removal of the tumor. The functional image of A always showed the tumor as a high-density area with a clear margin. P seemed to correlate with the degree of tumor vascularity, as seen on the angiogram. The dynamic CT with functional imaging does not seem to be of particular value in predicting the histologic nature of the tumor, but it is useful in studying the disturbance of cerebral blood flow in patients with intracranial tumors, and its restoration following the removal of the tumor. (author)

  11. PET/CT imaging: what radiologists need to know

    OpenAIRE

    Benamor, M.; Ollivier, L; Brisse, H; Moulin-Romsee, G.; Servois, V.; Neuenschwander, S.

    2007-01-01

    Abstract Positron emission tomography (PET)/computed tomography (CT) imaging is frequently requested in Oncology. Radiologists and nuclear medicine physicians are often asked to perform a panel of imaging examinations as part of the initial staging or follow-up of cancer patients. Medical imaging must therefore integrate polyvalent skills enabling imaging specialists to understand and interpret all types of images. In this context, PET imaging combined with non-enhanced CT, and diagnostic qua...

  12. PET/CT in lung cancer with brain metastases

    International Nuclear Information System (INIS)

    PET/CT is a method for diagnosis, staging and evaluating the effect of lung cancer treatment. The lung cancer is one of the cancers with most frequent localization of the metastases in brain. We have studied with 18 FDG-PET/CT 45 patients, 26 male (57.8%) and 19 female (42.2%) between 41 to 71 years of age, diagnosed with non-small cell lung cancer (NSCLC) or small cell lung cancer (SCLC) and brain metastases by 63 examinations. Examinations have been executed on integrated apparatus Phillips Gemini TF (2009). 18FDG has been applied by i.v. injection with activity 0.14 mCi/kg. Patients are staged by TNM classification. Survival has been evaluated by Kaplan-Meier method, for comparison of studied groups the log rank (Mantel-Cox) has been applied. (P<0.05). Multiple metastases in brain have been detected in 8 patients (17%). Hypo-metabolic have been found in 7 patients (14.9%), with hyper-metabolic - 10 (21.3%), with ring-like -7 (14.9%). In patients with metastases operated on, in the area of the operative intervention a hypo-metabolic zone has been found. New metastases have been found in 3 patients after operation. The median of survival of the patients with NSCLC in months for stage II and III has been estimated to 25.2 months and for stage IV to 12.9 months and total survival to 16.8 months (P=0.03). The median of survival in months for patients with NSCLC and SCLC in II and III stage is estimated to 28.4 months, for stage IV is estimated to 12.4 months and total survival is estimated to 16.8 months (P=0.04). Survival of the patients with NSCLC and SCLC with brain metastases is significantly dependent on the clinical stage. The median of survival in patients to III stage is double times longer than the median of survival of patients in IV stage. The median of total survival is estimated to 16.8 months. Most common histological form of the lung cancer in case of metastases in brain is adenocarcinoma. The established by PET/CT lesions in asymptomatic patients

  13. Fueling and imaging brain activation

    Directory of Open Access Journals (Sweden)

    Gerald A Dienel

    2012-07-01

    Full Text Available Metabolic signals are used for imaging and spectroscopic studies of brain function and disease and to elucidate the cellular basis of neuroenergetics. The major fuel for activated neurons and the models for neuron–astrocyte interactions have been controversial because discordant results are obtained in different experimental systems, some of which do not correspond to adult brain. In rats, the infrastructure to support the high energetic demands of adult brain is acquired during postnatal development and matures after weaning. The brain's capacity to supply and metabolize glucose and oxygen exceeds demand over a wide range of rates, and the hyperaemic response to functional activation is rapid. Oxidative metabolism provides most ATP, but glycolysis is frequently preferentially up-regulated during activation. Underestimation of glucose utilization rates with labelled glucose arises from increased lactate production, lactate diffusion via transporters and astrocytic gap junctions, and lactate release to blood and perivascular drainage. Increased pentose shunt pathway flux also causes label loss from C1 of glucose. Glucose analogues are used to assay cellular activities, but interpretation of results is uncertain due to insufficient characterization of transport and phosphorylation kinetics. Brain activation in subjects with low blood-lactate levels causes a brain-to-blood lactate gradient, with rapid lactate release. In contrast, lactate flooding of brain during physical activity or infusion provides an opportunistic, supplemental fuel. Available evidence indicates that lactate shuttling coupled to its local oxidation during activation is a small fraction of glucose oxidation. Developmental, experimental, and physiological context is critical for interpretation of metabolic studies in terms of theoretical models.

  14. Use of automated image registration to generate mean brain SPECT image of Alzheimer's patients

    International Nuclear Information System (INIS)

    The purpose of this study was to compute and compare the group mean HMPAO brain SPECT images of patients with senile dementia of Alzheimer's type (SDAT) and age matched control subjects after transformation of the individual images to a standard size and shape. Ten patients with Alzheimer's disease (age 71.6±5.0 yr) and ten age matched normal subjects (age 71.0±6.1 yr) participated in this study. Tc-99m HMPAO brain SPECT and X-ray CT scans were acquired for each subject. SPECT images were normalized to an average activity of 100 counts/pixel. Individual brain images were transformed to a standard size and shape with the help of Automated Image Registration (AIR). Realigned brain SPECT images of both groups were used to generate mean and standard deviation images by arithmetic operations on voxel based numerical values. Mean images of both groups were compared by applying the unpaired t-test on a voxel by voxel basis to generate three dimensional T-maps. X-ray CT images of individual subjects were evaluated by means of a computer program for brain atrophy. A significant decrease in relative radioisotope (RI) uptake was present in the bilateral superior and inferior parietal lobules (p<0.05), bilateral inferior temporal gyri, and the bilateral superior and middle frontal gyri (p<0.001). The mean brain atrophy indices for patients and normal subjects were 0.853±0.042 and 0.933±0.017 respectively, the difference being statistically significant (p<0.001). The use of a brain image standardization procedure increases the accuracy of voxel based group comparisons. Thus, intersubject averaging enhances the capacity for detection of abnormalities in functional brain images by minimizing the influence of individual variation. (author)

  15. Wilson's disease with peculiar MR-CT imaging

    International Nuclear Information System (INIS)

    A 15-year-old boy was admitted to our hospital complaining of progressive right hemiparesis and dysarthria. The diagnosis of Wilson's disease was established by Kayser-Fleischer rings and biochemical examinations, including low plasma copper and ceruloplasmin concertration. A paternal cousin was known to be Wilson's disease and died at 10 years of age. The brain CT scan demonstrated low density areas in bilateral thalami and lentiform nuclei. In addition, bilateral frontal lobes, and left temporal lobe showed a large low density area. The brain MR-CT demonstrated long T1 (dark) area on IR scans and long T2 (light) area on SE scans in bilateral thalami, and lentiform nuclei. The gross leisions in bilateral frontal lobes and left temporal lobe were imaged as dark areas on IR as well as on SE scans. We suggested that the latter may reflect the formation of gross cavities corresponding to the loss of excessive amount of white matter, rarely reported in the autopsy cases in the literature. (author)

  16. MR image-guided portal verification for brain treatment field

    International Nuclear Information System (INIS)

    Purpose: To investigate a method for the generation of digitally reconstructed radiographs directly from MR images (DRR-MRI) to guide a computerized portal verification procedure. Methods and Materials: Several major steps were developed to perform an MR image-guided portal verification procedure. Initially, a wavelet-based multiresolution adaptive thresholding method was used to segment the skin slice-by-slice in MR brain axial images. Some selected anatomical structures, such as target volume and critical organs, were then manually identified and were reassigned to relatively higher intensities. Interslice information was interpolated with a directional method to achieve comparable display resolution in three dimensions. Next, a ray-tracing method was used to generate a DRR-MRI image at the planned treatment position, and the ray tracing was simply performed on summation of voxels along the ray. The skin and its relative positions were also projected to the DRR-MRI and were used to guide the search of similar features in the portal image. A Canny edge detector was used to enhance the brain contour in both portal and simulation images. The skin in the brain portal image was then extracted using a knowledge-based searching technique. Finally, a Chamfer matching technique was used to correlate features between DRR-MRI and portal image. Results: The MR image-guided portal verification method was evaluated using a brain phantom case and a clinical patient case. Both DRR-CT and DRR-MRI were generated using CT and MR phantom images with the same beam orientation and then compared. The matching result indicated that the maximum deviation of internal structures was less than 1 mm. The segmented results for brain MR slice images indicated that a wavelet-based image segmentation technique provided a reasonable estimation for the brain skin. For the clinical patient case with a given portal field, the MR image-guided verification method provided an excellent match between

  17. Neural network and its application to CT imaging

    International Nuclear Information System (INIS)

    We present an integrated approach to imaging the progress of air displacement by spontaneous imbibition of oil into sandstone. We combine Computerized Tomography (CT) scanning and neural network image processing. The main aspects of our approach are (I) visualization of the distribution of oil and air saturation by CT, (II) interpretation of CT scans using neural networks, and (III) reconstruction of 3-D images of oil saturation from the CT scans with a neural network model. Excellent agreement between the actual images and the neural network predictions is found

  18. Neural network and its application to CT imaging

    Energy Technology Data Exchange (ETDEWEB)

    Nikravesh, M.; Kovscek, A.R.; Patzek, T.W. [Lawrence Berkeley National Lab., CA (United States)] [and others

    1997-02-01

    We present an integrated approach to imaging the progress of air displacement by spontaneous imbibition of oil into sandstone. We combine Computerized Tomography (CT) scanning and neural network image processing. The main aspects of our approach are (I) visualization of the distribution of oil and air saturation by CT, (II) interpretation of CT scans using neural networks, and (III) reconstruction of 3-D images of oil saturation from the CT scans with a neural network model. Excellent agreement between the actual images and the neural network predictions is found.

  19. Cirrhosis: CT and MR imaging evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Brancatelli, Giuseppe [Sezione di Radiologia, Ospedale Specializzato in Gastroenterologia, ' Saverio de Bellis' -IRCCS, 70013 Castellana Grotte (Bari) (Italy) and Sezione di Scienze Radiologiche, Dipartimento di Biotecnologie Mediche e Medicina Legale, Universita di Palermo, Via del Vespro 127, 90127 Palermo (Italy) and Department of Radiology, University of Pittsburgh Medical Center, 200 Lothrop Street, 15213 Pittsburgh, PA (United States)]. E-mail: gbranca@yahoo.com; Federle, Michael P. [Department of Radiology, University of Pittsburgh Medical Center, 200 Lothrop Street, 15213 Pittsburgh, PA (United States); Ambrosini, Roberta [Department of Diagnostic and Interventional Radiology, ' Maggiore della Carita' University Hospital, ' A.Avogadro' Eastern Piemonte University, Corso Mazzini 18, Novara (Italy); Lagalla, Roberto [Sezione di Scienze Radiologiche, Dipartimento di Biotecnologie Mediche e Medicina Legale, Universita di Palermo, Via del Vespro 127, 90127 Palermo (Italy); Carriero, Alessandro [Department of Diagnostic and Interventional Radiology, ' Maggiore della Carita' University Hospital, ' A.Avogadro' Eastern Piemonte University, Corso Mazzini 18, Novara (Italy); Midiri, Massimo [Sezione di Scienze Radiologiche, Dipartimento di Biotecnologie Mediche e Medicina Legale, Universita di Palermo, Via del Vespro 127, 90127 Palermo (Italy); Vilgrain, Valerie [Service de Radiologie, Hopital Beaujon, 100 Boulevard du General Leclerc, 92118 Clichy (France)

    2007-01-15

    In this article, we present the CT and MR imaging characteristics of the cirrhotic liver. We describe the altered liver morphology in different forms of viral, alcoholic and autoimmune end-stage liver disease. We present the spectrum of imaging findings in portal hypertension, such as splenomegaly, ascites and varices. We describe the patchy and lacelike patterns of fibrosis, along with the focal confluent form. The process of hepatocarcinogenesis is detailed, from regenerative to dysplastic nodules to overt hepatocellular carcinoma. Different types of non-neoplastic focal liver lesions occurring in the cirrhotic liver are discussed, including arterially enhancing nodules, hemangiomas and peribiliary cysts. We show different conditions causing liver morphology changes that can mimic cirrhosis, such as congenital hepatic fibrosis, 'pseudo-cirrhosis' due to breast metastases treated with chemotherapy, Budd-Chiari syndrome, sarcoidosis and cavernous transformation of the portal vein.

  20. Brain imaging studies of sleep disorder

    International Nuclear Information System (INIS)

    Brain imaging studies of narcolepsy (NA)/cataplexy (CA), a typical sleep disorder, are summarized together with techniques of functional and structural imaging means. single photon emission CT (SPECT) is based on the distribution of tracers labeled by single photon emitters like 99mTc and 123I for seeing the blood flow and receptors. PET using positron emitters like 15O and 18F for blood flow and for glucose metabolism, respectively, is of higher resolution and more quantitative than SPECT. Functional MRI (fMRI) depicts the cerebral activity through signal difference by blood oxygenation level dependence (BOLD) effect, and MR spectroscopy (MRS) depicts and quantifies biomaterials through the difference of their nuclear chemical shifts in the magnetic field. Morphologic imaging studies involve the measurement of the volume of the region of interest by comparison with the reference region such as the whole brain volume. Voxel-based morphometry (VBM) has changed to its more advanced surface-based analysis (SBA) of T1-enhanced image. Diffusion tensor imaging (DTI) is based on the tissue water diffusion. Functional SPECT/PET studies have suggested the decrease of blood flow and metabolic activity in the hypothalamus (HT) and other related regions at the conscious resting state, and locally increased blood flow in cingulate gyrus (CG) and amygdaloid complex (AC) at affective CA/PA seizure. fMRI has suggested the hypoactivity of HT and hyperactivity of AC at the seizure. VBM-based studies have not given the consistent results, but DTI studies have suggested an important participation of AC at the seizure. (T.T.)

  1. An approach for quantitative image quality analysis for CT

    Science.gov (United States)

    Rahimi, Amir; Cochran, Joe; Mooney, Doug; Regensburger, Joe

    2016-03-01

    An objective and standardized approach to assess image quality of Compute Tomography (CT) systems is required in a wide variety of imaging processes to identify CT systems appropriate for a given application. We present an overview of the framework we have developed to help standardize and to objectively assess CT image quality for different models of CT scanners used for security applications. Within this framework, we have developed methods to quantitatively measure metrics that should correlate with feature identification, detection accuracy and precision, and image registration capabilities of CT machines and to identify strengths and weaknesses in different CT imaging technologies in transportation security. To that end we have designed, developed and constructed phantoms that allow for systematic and repeatable measurements of roughly 88 image quality metrics, representing modulation transfer function, noise equivalent quanta, noise power spectra, slice sensitivity profiles, streak artifacts, CT number uniformity, CT number consistency, object length accuracy, CT number path length consistency, and object registration. Furthermore, we have developed a sophisticated MATLAB based image analysis tool kit to analyze CT generated images of phantoms and report these metrics in a format that is standardized across the considered models of CT scanners, allowing for comparative image quality analysis within a CT model or between different CT models. In addition, we have developed a modified sparse principal component analysis (SPCA) method to generate a modified set of PCA components as compared to the standard principal component analysis (PCA) with sparse loadings in conjunction with Hotelling T2 statistical analysis method to compare, qualify, and detect faults in the tested systems.

  2. Evaluation of Marfan syndrome: MR imaging versus CT

    International Nuclear Information System (INIS)

    Twenty-five patients with Marfan, syndrome underwent both CT and MR imaging. MR imaging were interpreted in blinded fashion and then compared with CT scans MR imaging was found to be equivalent to CT in the detection of aortic, dural, and hip abnormalities in patients not operated on. MR imaging was superior to CT in the evaluation of postoperative patients because the artifact produced by Bjork-Shirley or St. Jude valves precludes adequate evaluation of the aortic root on CT while producing only a small inferior field distortion (a ''pseudo-ventricular septal defect'') on MR imaging. The absence of radiation exposure is another major advantage of MR imaging in this relatively young population requiring serial studies. The authors conclude that MR imaging is the modality of choice for the evaluation and follow-up of patients with Marfan syndrome and offers an appropriate means of screening their kindred

  3. A hybrid algorithm for PET/CT image merger in hybrid scanners

    International Nuclear Information System (INIS)

    To improve the PET image quality of a hybrid PET/CT scanner by merging CT borders with PET texture. PET/CT scanners provide both high-resolution CT images showing anatomical details and PET images of low-resolution physiological information about radiopharmaceutical uptake. Standard smoothing of noisy PET images may further impair PET resolution, reducing small lesion detectability. The CT edge data and the PET texture data were merged using a modified form of an algorithm called HCT (hybrid computed tomography). In merged PET/CT images, each PET pixel value was estimated by iteratively applying a corrected 2D Taylor expansion to each of its eight neighbors. The spatial derivative term was used only near anatomical edges provided by the CT. This counts-preserving algorithm was tested on a special resolution phantom and patient data sets obtained by PET/CT acquisitions. The HCT algorithm provided phantom PET images with sharp borders and improved resolution (≤3 mm as compared to ≥4 mm). HCT increased the signal to background contrast ratios by an average of 61% (40-89%) while maintaining noise reduction similar to the Gaussian filtering standard in PET. In the clinical PET images, HCT allowed for an improved delineation of pulmonary and pelvic lesions and an improved visualization of the brain. A new reconstruction algorithm for merging CT anatomical edge data with functional PET data has been introduced. The algorithm smoothes noisy PET images while retaining sharper edges at corresponding anatomical borders, resulting in an improvement in resolution and contrast ratio. (orig.)

  4. Targeted Gold Nanoparticles enable Molecular CT Imaging of Cancer

    OpenAIRE

    Popovtzer, Rachela; Agrawal, Ashish; Kotov, Nicholas A.; Popovtzer, Aron; Balter, James; Carey, Thomas E.; Kopelman, Raoul

    2008-01-01

    X-ray based computed tomography (CT), is among the most convenient imaging/diagnostic tools in hospitals today in terms of availability, efficiency and cost. However, in contrast to magnetic resonance imaging (MRI) and various nuclear medicine imaging modalities, CT is not considered a molecular imaging modality since targeted and molecularly specific contrast agents have not yet been developed. Here we describe a targeted molecular imaging platform that enables, for the first time, cancer de...

  5. Brain CT Images Analysis of Chronic Alcoholism Encephalopathy%60例慢性酒精中毒所致精神障碍患者颅脑CT图像分析

    Institute of Scientific and Technical Information of China (English)

    夏从羊; 冯晓强; 王德阳

    2012-01-01

    目的 分析慢性酒精中毒所致精神障碍颅脑CT表现特征.方法 对60例慢性酒精中毒所致精神障碍患者颅脑CT表现进行总结.结果 主要表现为不同程度的脑萎缩,脑白质区缺血、变性,脱髓鞘改变,腔隙性脑梗死和脑内软化灶.其中,大脑萎缩20例,小脑萎缩19例,大脑与小脑同时萎缩12例,脑萎缩合并软化灶9例,脑萎缩合并脑白质区缺血、变性,腔隙性脑梗死6例.结论 慢性酒精中毒所致精神障碍颅脑CT表现特征是不同程度的脑萎缩,脑白质缺血、变性脱髓鞘改变,腔隙性脑梗死和脑内软化灶.%Objective To Analyze of characteristics of chronic alcoholism due to mental disorder in brain CT manifestations.Method 60 cases of chronic alcoholism induced mental disorders in patients with biain CT findings were summarized.Results Main features are varying degrees of brain atrophy,white matter ischemia,degenation, demyelination,lacunar infarction and cerebral softening foci.Among them are 20 cases of brain atrophy,cerebellar atrophy in 19 cases,the brain and cerebellar atrophy simultaneously in 12 cases,9 cases of brain atrophy with softening,brain atrophy and white matter ischemia,degeneration,cerebral lacunar infarction in 6.Conclusion Chronic alcoholism mental disorder in brain CT manifestations characterized by varying degrees of brain atrophy,degeneration of ischemia,cerebral white matter areas,lacunar cerebral infarction and cerebral softening foci.

  6. Multidetector CT: contributions in liver imaging

    International Nuclear Information System (INIS)

    Multidetector CT has had great impact in the evaluation of the liver. Increased speed combined with thin slice collimation improved the spatial and temporal resolution, which in turn provided a higher sensitivity in the detection of focal lesions, particularly for the hepatocellular cancer (HCC) in patients with cirrhosis. There is no consensus as to whether the so-called 'double arterial phase scanning' improves the detection rate of hepatocellular cancers, and the majority of the more recent studies suggest acquiring only the late arterial phase images along with the portal venous phase images. However, if the patient is a surgical candidate, the early arterial phase images must also be obtained, because they provide better pre-surgical mapping of the hepatic arteries. In primary and metastatic liver tumors, arterial and portal venous phase images should be acquired with thin collimation and overlapping reconstruction. Maximum intensity projection and volume rendering methods demonstrate the three-dimensional anatomy of the hepatic arteries, portal and hepatic veins successfully, which provide useful information before hepatic resection or intraarterial chemotherapy. In living donor candidates, early arterial and portal venous phase images obtained with thin collimation and overlapping reconstruction are used to reconstruct three-dimensional images with maximum intensity and volume rendering methods. These have a high sensitivity to detect hepatic artery, portal and hepatic vein variations, which could render the surgery difficult or even impossible. Portal venous phase images can also be used to measure total and lobar liver volumes. A virtual hepatectomy plane can be simulated on the three-dimensional model of the liver and hepatic veins, and when necessary, its location can be modified according to the metabolic needs of the recipient and donor. Thin collimation and better temporal resolution may also have beneficial effects in the characterization of liver

  7. Imaging study of brain damage from methanol intoxication of wine

    International Nuclear Information System (INIS)

    Objective: To investigate the imaging of CT and MRI in brain damage caused by methanol intoxication from false wine, and to study the relations between imaging manifestation and different degrees of the methanol intoxication. Method: Thirty nine cases with methanol intoxication from false wine were retrospectively reported, The latent period of these patients was 0-4 days, and the average latent period of these patients was 0.5 days, All cases were performed by serology examination, brain CT scan, and four cases performed by MRI scan after average 2.5 days (range, 1-6 days) the onset of methanol intoxication. Results: Six cases showed hyperintense signals in bilateral putamen, two cases also showed hyperintense signals in biolateral subcortex white substance regions. Four cases showed hyperintense signals in unilateral internal capsule. One case showed hyperintense changess in subcortex white substance regions. Our study showed the positive correlation between CT features and the amount of methanol and stage of clinic manifestation(χ2=4.232, P2=0.001, P>0.05). Conclusions: MRI was better than CT in finding early brain damage caused by methanol intoxication from false wine. The characteristic finding changes of the patients was showed mainly in in bilateral putamen, Prognosis for the patients combined with subcortex white substance lesion wasn't hopeful. (authors)

  8. Soft tissue imaging with photon counting spectroscopic CT

    Science.gov (United States)

    Shikhaliev, Polad M.

    2015-03-01

    The purpose of this work was experimental investigation of photon counting spectroscopic CT (PCS-CT) imaging of anatomical soft tissue with clinically relevant size. The imaging experiments were performed using a spectroscopic CT system based on CdZnTe photon counting detector with two rows of pixels, 256 pixels in each row, 1  ×  1 mm2 pixel size, and 25.6 cm detector length. The detector could split the x-ray energy spectrum to 5 regions (energy bins), and acquire 5 multi-energy (spectroscopic) CT images in a single CT scan. A sample of round shaped anatomical soft tissue of 14 cm diameter including lean and fat was used for imaging. To avoid the negative effect of anatomical noise on quantitative analysis, a spectroscopic CT phantom with tissue equivalent solid materials was used. The images were acquired at 60, 90, and 120 kVp tube voltages, and spectroscopic image series were acquired with 3 and 5 energy bins. Spectroscopic CT numbers were introduced and used to evaluate an energy selective image series. The anatomical soft tissue with 14 cm diameter was visualized with good quality and without substantial artifacts by the photon counting spectroscopic CT system. The effects of the energy bin crosstalk on spectroscopic CT numbers were quantified and analyzed. The single and double slice PCS-CT images were acquired and compared. Several new findings were observed, including the effect of soft tissue non-uniformity on image artifacts, unique status of highest energy bin, and material dependent visualization in spectroscopic image series. Fat-lean decomposition was performed using dual energy subtraction and threshold segmentation methods, and compared. Using K-edge filtered x-rays improved fat-lean decomposition as compared to conventional x-rays. Several new and important aspects of the PCS-CT were investigated. These include imaging soft tissue with clinically relevant size, single- and double-slice PCS-CT imaging, using spectroscopic CT

  9. 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.

  10. Virtual monochromatic imaging in dual-source dual-energy CT: Radiation dose and image quality

    OpenAIRE

    Yu, Lifeng; Christner, Jodie A.; Leng, Shuai; Wang, Jia; Fletcher, Joel G.; McCollough, Cynthia H.

    2011-01-01

    Purpose: To evaluate the image quality of virtual monochromatic images synthesized from dual-source dual-energy computed tomography (CT) in comparison with conventional polychromatic single-energy CT for the same radiation dose.

  11. Molecular Imaging with Small Animal PET/CT

    DEFF Research Database (Denmark)

    Binderup, T.; El-Ali, H.H.; Skovgaard, D.;

    2011-01-01

    Small animal positron emission tomography (PET) and computer tomography (CT) is an emerging field in pre-clinical imaging. High quality, state-of-the-art instruments are required for full optimization of the translational value of the small animal studies with PET and CT. However, with this achie...... small animal PET/CT for studies of muscle and tendon in exercise models. © 2011 Bentham Science Publishers Ltd.......Small animal positron emission tomography (PET) and computer tomography (CT) is an emerging field in pre-clinical imaging. High quality, state-of-the-art instruments are required for full optimization of the translational value of the small animal studies with PET and CT. However, with this...... this field of small animal molecular imaging with special emphasis on the targets for tissue characterization in tumor biology such as hypoxia, proliferation and cancer specific over-expression of receptors. The added value of applying CT imaging for anatomical localization and tumor volume...

  12. Functional brain imaging; Funktionelle Hirnbildgebung

    Energy Technology Data Exchange (ETDEWEB)

    Gizewski, E.R. [Medizinische Universitaet Innsbruck, Universitaetsklinik fuer Neuroradiologie, Innsbruck (Austria)

    2016-02-15

    Functional magnetic resonance imaging (fMRI) is a non-invasive method that has become one of the major tools for understanding human brain function and in recent years has also been developed for clinical applications. Changes in hemodynamic signals correspond to changes in neuronal activity with good spatial and temporal resolution in fMRI. Using high-field MR systems and increasingly dedicated statistics and postprocessing, activated brain areas can be detected and superimposed on anatomical images. Currently, fMRI data are often combined in multimodal imaging, e. g. with diffusion tensor imaging (DTI) sequences. This method is helping to further understand the physiology of cognitive brain processes and is also being used in a number of clinical applications. In addition to the blood oxygenation level-dependent (BOLD) signals, this article deals with the construction of fMRI investigations, selection of paradigms and evaluation in the clinical routine. Clinically, this method is mainly used in the planning of brain surgery, analyzing the location of brain tumors in relation to eloquent brain areas and the lateralization of language processing. As the BOLD signal is dependent on the strength of the magnetic field as well as other limitations, an overview of recent developments is given. Increases of magnetic field strength (7 T), available head coils and advances in MRI analytical methods have led to constant improvement in fMRI signals and experimental design. Especially the depiction of eloquent brain regions can be done easily and quickly and has become an essential part of presurgical planning. (orig.) [German] Mittlerweile ist die funktionelle MRT (fMRT) eine Methode, die nicht mehr nur in der neurowissenschaftlichen Routine verwendet wird. Die fMRT ermoeglicht die nichtinvasive Darstellung der Hirnaktivitaet in guter raeumlicher und zeitlicher Aufloesung unter Ausnutzung der Durchblutungsaenderung aufgrund der erhoehten Nervenzellaktivitaet. Unter

  13. Superiority of CT imaging reconstruction on Linux OS

    International Nuclear Information System (INIS)

    Objective: To compare the speed of CT reconstruction using the Linux and Windows OS. Methods: Shepp-Logan head phantom in different pixel size was projected to obtain the sinogram by using the inverse Fourier transformation, filtered back projection and Radon transformation on both Linux and Windows OS. Results: CT image reconstruction using the Linux operating system was significantly better and more efficient than Windows. Conclusion: CT image reconstruction using the Linux operating system is more efficient. (authors)

  14. Thin slice thickness double-dose contrast-enhanced CT in the detection of brain metastases

    International Nuclear Information System (INIS)

    To compare the usefulness of double-dose contrast-enhanced CT (DDCE-CT) and conventional contrast-enhanced CT(CCE-CT) in the detection of metastatic brain lesions. Sixteen patients with brain metastases were evaluated with both CCE-CT and thin-slice DDCE-CT. For CCE-CT, and initial injection of the 100 ml contrast medium was given, and DDCE-CT with both 10-mm and 5-mm thickness was performed after the addition of an extra 100 ml of contrast medium. The numbers of metastatic lesions detected by CCE-CT and by DDCE-CT were compared, as were the findings of contrast-enhanced MRI (CE-MRI) and thin-slice DDCE-CT in seven patients who underwent both these procedures. Fourteen metastatic brain lesions were detected by CCE-CT, 22 by 10-mm-thickness DDCE-CT than by CCE-CT. Metastatic lesions were detected by 10-mm-thickness DDCE-CT and 5-mm-thickness DDCE-CT detected seven and 18 lesions, respectively. Eleven lesions were detected by thin-slice DDCE-CT and 17 by CE-MRI in the seven patients who underwent both CE-MRI and DDCE-CT. The lesions detected only by CE-MRI were less than 5 mm in diameter and were discovered in the cerebellum or inferior temporal lobe. Thin-slice DDCE-CT was superior to CCE-CT in detecting metastatic brain lesions

  15. Quantitative imaging of brain chemistry

    International Nuclear Information System (INIS)

    We can now measure how chemicals affect different regions of the human brain. One area involves the study of drugs - in-vivo neuro-pharmacology; another involves the study of toxic chemical effects - in vivo neurotoxicology. The authors approach is to label drugs with positron-emitting radioactive tracers - chiefly carbon-11 with a half-life of 20 minutes and fluorine-18 with a half-life of 110 minutes. The labeled drugs are injected intravenously and a positron emission tomography (PET) scanner is used to map out the distribution of the radioactivity within the brain from the moment of injection until about 90 minutes later. Mathematical models are used to calculate receptor concentrations and the affinity of the receptors for the injected radioactive tracer. By means of PET scanning, they look at cross sections or visual slices throughout the human brain, obtaining computer-generated images in any plane. The authors are investigating the functions of specific drugs or specific receptors, as well as looking at the metabolic activity in different parts of the brain as revealed in glucose metabolism. For example, the authors are studying opiate receptors in patients with a variety of conditions: those who suffer from chronic pain, those who are congenitally insensitive to pain and drug addicts. They are studying patients with schizophrenia, tardive dyskinesia, Parkinson's disease, Huntington's disease, depressed patients and sex-offenders. They are relating the state of the neurotransmitter/neuroreceptor systems to behavior. In essence, they believe that they can now examine in living human beings what relates the structure of the brain to the function of the mind that is chemistry

  16. CT and MR imaging of intracranial tuberous sclerosis

    International Nuclear Information System (INIS)

    CT and MR have permitted radiology to play a greater, but not definitive, role in detecting the pathologic components of tuberous sclerosis. SEN may be identified in only 80% of patients. Tubers are more ubiquitous and readily identified by MR in children and adults when the brain is myelinated. Since tubers are predominately peripheral hypomyelinated lesions, the detection of small lesions may be delayed until an infant is over 16-18 months of age when the myelin will have extended to the junction between the cortical white and gray matter. SEGA typically evolve later during the first and second decades of life. Successful genetic counseling implies a need to detect tuberous sclerosis at a stage during infancy when imaging may fail to confirm the diagnosis, so tuberous sclerosis remains a clinical diagnosis. (author)

  17. Analysis methods of noise extraction from CT images

    OpenAIRE

    Ioan Gavriluţ; Alexandru Gacsádi; Cristian Grava; Oreste Straciuc; Laviniu Ţepelea

    2009-01-01

    This paper presents a comparativeanalysis of the efficiency of certain filters used forextracting the noise from CT (Computer Tomography)images. Appreciation of filtration methods is based onthe use of mean squared error and direct visualizationof the real medical images.

  18. Virtual colonoscopy using CT and MR imaging

    International Nuclear Information System (INIS)

    Purpose: To evaluate experimentally and in patients the sensitivity and effective dose of virtual electron-beam tomography (EBT) colonoscopy for detecting small colon tumors and to compare the methods and results with virtual colonoscopy using spiral CT and MR imaging in a review of the literature. Results: In the tumor model, all polyps were detectable at a pitch of 1.5. A further reduction of the pitch ratio did not improve the conspicuity of the polyps. In patient studies, all tumors (n=4) and polyps (n=3) were correctly identified on 3D fly-throughs. Two false positive results were obtained. Effective dose equivalent was calculated at 3.2 mSv per scan. (orig./AJ)

  19. Automatic Lumbar Spondylolisthesis Measurement in CT Images.

    Science.gov (United States)

    Liao, Shu; Zhan, Yiqiang; Dong, Zhongxing; Yan, Ruyi; Gong, Liyan; Zhou, Xiang Sean; Salganicoff, Marcos; Fei, Jun

    2016-07-01

    Lumbar spondylolisthesis is one of the most common spinal diseases. It is caused by the anterior shift of a lumbar vertebrae relative to subjacent vertebrae. In current clinical practices, staging of spondylolisthesis is often conducted in a qualitative way. Although meyerding grading opens the door to stage spondylolisthesis in a more quantitative way, it relies on the manual measurement, which is time consuming and irreproducible. Thus, an automatic measurement algorithm becomes desirable for spondylolisthesis diagnosis and staging. However, there are two challenges. 1) Accurate detection of the most anterior and posterior points on the superior and inferior surfaces of each lumbar vertebrae. Due to the small size of the vertebrae, slight errors of detection may lead to significant measurement errors, hence, wrong disease stages. 2) Automatic localize and label each lumbar vertebrae is required to provide the semantic meaning of the measurement. It is difficult since different lumbar vertebraes have high similarity of both shape and image appearance. To resolve these challenges, a new auto measurement framework is proposed with two major contributions: First, a learning based spine labeling method that integrates both the image appearance and spine geometry information is designed to detect lumbar vertebrae. Second, a hierarchical method using both the population information from atlases and domain-specific information in the target image is proposed for most anterior and posterior points positioning. Validated on 258 CT spondylolisthesis patients, our method shows very similar results to manual measurements by radiologists and significantly increases the measurement efficiency. PMID:26849859

  20. Segmentation of liver tumors on CT images

    International Nuclear Information System (INIS)

    This thesis is dedicated to 3D segmentation of liver tumors in CT images. This is a task of great clinical interest since it allows physicians benefiting from reproducible and reliable methods for segmenting such lesions. Accurate segmentation would indeed help them during the evaluation of the lesions, the choice of treatment and treatment planning. Such a complex segmentation task should cope with three main scientific challenges: (i) the highly variable shape of the structures being sought, (ii) their similarity of appearance compared with their surrounding medium and finally (iii) the low signal to noise ratio being observed in these images. This problem is addressed in a clinical context through a two step approach, consisting of the segmentation of the entire liver envelope, before segmenting the tumors which are present within the envelope. We begin by proposing an atlas-based approach for computing pathological liver envelopes. Initially images are pre-processed to compute the envelopes that wrap around binary masks in an attempt to obtain liver envelopes from estimated segmentation of healthy liver parenchyma. A new statistical atlas is then introduced and used to segmentation through its diffeomorphic registration to the new image. This segmentation is achieved through the combination of image matching costs as well as spatial and appearance prior using a multi-scale approach with MRF. The second step of our approach is dedicated to lesions segmentation contained within the envelopes using a combination of machine learning techniques and graph based methods. First, an appropriate feature space is considered that involves texture descriptors being determined through filtering using various scales and orientations. Then, state of the art machine learning techniques are used to determine the most relevant features, as well as the hyper plane that separates the feature space of tumoral voxels to the ones corresponding to healthy tissues. Segmentation is then

  1. Brain atrophy and dementia from the aspect of CT

    International Nuclear Information System (INIS)

    Two major causes of dementia in the elderly are reported to be the degeneration of brain and cerebrovascular diseases. Recently, CT findings of cerebrovascular diseases and brain atrophy have been noticed, because they rather clearly show these changes. The authors examined the view of atrophy frequently observed on the dementia in the elderly. The results obtained are as follows: 1) In accordance with the increase of age the appearance of the view of atrophy increased in frequency and that of extreme brain atrophy also increased. 2) As the age increased, the average value of the width of the 3rd ventricle tended to increase. 3) In the cases accompanied with the view of cerebrovascular diseases remarkable ventricular dilatation was frequently observed, and in the very old dilatations of cerebral sulci, central fissure and Sylvian fissure were observed of all cases. 4) Of the group of severe dementia the view of extreme brain atrophy was observed in the major. However, there was no significant difference on the lesion of atrophy between the cases. The results mentioned above include some exceptional points respectively, so further investigation will be necessary from the qualitative and quantitative points of view. (author)

  2. Personal computer aided cerebral perfusion imaging with dynamic CT

    Institute of Scientific and Technical Information of China (English)

    林燕; 高培毅

    2004-01-01

    @@Reports on the clinical implementation of dynamic computerised tomography (CT) perfusion imaging and quantitative measurement have increased dramatically of late.1-8 The advantages of dynamic CT perfusion imaging and quantitative measurement for the diagnosis of acute cerebral infarction have been acknowledged. However, most overseas CT vendors set perfusion imaging software package as an option for graphic workstation at a too high price for domestic practitioners. To foster the domestic implementation and development of this new technology, we have extended the earlier work.1,2 Applying the theory of central volume principle to DICOM 3.0 standard forms of prime CT images, we developed dynamic CT perfusion imaging and quantitative measure-ment programmes for PCs using Visual C+ + in Windows 98 system.

  3. Non-Rigid Registration of Liver CT Images for CT-Guided Ablation of Liver Tumors.

    Science.gov (United States)

    Luu, Ha Manh; Klink, Camiel; Niessen, Wiro; Moelker, Adriaan; Walsum, Theo van

    2016-01-01

    CT-guided percutaneous ablation for liver cancer treatment is a relevant technique for patients not eligible for surgery and with tumors that are inconspicuous on US imaging. The lack of real-time imaging and the use of a limited amount of CT contrast agent make targeting the tumor with the needle challenging. In this study, we evaluate a registration framework that allows the integration of diagnostic pre-operative contrast enhanced CT images and intra-operative non-contrast enhanced CT images to improve image guidance in the intervention. The liver and tumor are segmented in the pre-operative contrast enhanced CT images. Next, the contrast enhanced image is registered to the intra-operative CT images in a two-stage approach. First, the contrast-enhanced diagnostic image is non-rigidly registered to a non-contrast enhanced image that is conventionally acquired at the start of the intervention. In case the initial registration is not sufficiently accurate, a refinement step is applied using non-rigid registration method with a local rigidity term. In the second stage, the intra-operative CT-images that are used to check the needle position, which often consist of only a few slices, are registered rigidly to the intra-operative image that was acquired at the start of the intervention. Subsequently, the diagnostic image is registered to the current intra-operative image, using both transformations, this allows the visualization of the tumor region extracted from pre-operative data in the intra-operative CT images containing needle. The method is evaluated on imaging data of 19 patients at the Erasmus MC. Quantitative evaluation is performed using the Dice metric, mean surface distance of the liver border and corresponding landmarks in the diagnostic and the intra-operative images. The registration of the diagnostic CT image to the initial intra-operative CT image did not require a refinement step in 13 cases. For those cases, the resulting registration had a Dice

  4. Head and neck imaging with PET and PET/CT: artefacts from dental metallic implants

    International Nuclear Information System (INIS)

    Germanium-68 based attenuation correction (PETGe68) is performed in positron emission tomography (PET) imaging for quantitative measurements. With the recent introduction of combined in-line PET/CT scanners, CT data can be used for attenuation correction. Since dental implants can cause artefacts in CT images, CT-based attenuation correction (PETCT) may induce artefacts in PET images. The purpose of this study was to evaluate the influence of dental metallic artwork on the quality of PET images by comparing non-corrected images and images attenuation corrected by PETGe68 and PETCT. Imaging was performed on a novel in-line PET/CT system using a 40-mAs scan for PETCT in 41 consecutive patients with high suspicion of malignant or inflammatory disease. In 17 patients, additional PETGe68 images were acquired in the same imaging session. Visual analysis of fluorine-18 fluorodeoxyglucose (FDG) distribution in several regions of the head and neck was scored on a 4-point scale in comparison with normal grey matter of the brain in the corresponding PET images. In addition, artefacts adjacent to dental metallic artwork were evaluated. A significant difference in image quality scoring was found only for the lips and the tip of the nose, which appeared darker on non-corrected than on corrected PET images. In 33 patients, artefacts were seen on CT, and in 28 of these patients, artefacts were also seen on PET imaging. In eight patients without implants, artefacts were seen neither on CT nor on PET images. Direct comparison of PETGe68 and PETCT images showed a different appearance of artefacts in 3 of 17 patients. Malignant lesions were equally well visible using both transmission correction methods. Dental implants, non-removable bridgework etc. can cause artefacts in attenuation-corrected images using either a conventional 68Ge transmission source or the CT scan obtained with a combined PET/CT camera. We recommend that the non-attenuation-corrected PET images also be evaluated

  5. Wavelet Based Image Fusion for Detection of Brain Tumor

    Directory of Open Access Journals (Sweden)

    CYN Dwith

    2013-01-01

    Full Text Available Brain tumor, is one of the major causes for the increase in mortality among children and adults. Detecting the regions of brain is the major challenge in tumor detection. In the field of medical image processing, multi sensor images are widely being used as potential sources to detect brain tumor. In this paper, a wavelet based image fusion algorithm is applied on the Magnetic Resonance (MR images and Computed Tomography (CT images which are used as primary sources to extract the redundant and complementary information in order to enhance the tumor detection in the resultant fused image. The main features taken into account for detection of brain tumor are location of tumor and size of the tumor, which is further optimized through fusion of images using various wavelet transforms parameters. We discuss and enforce the principle of evaluating and comparing the performance of the algorithm applied to the images with respect to various wavelets type used for the wavelet analysis. The performance efficiency of the algorithm is evaluated on the basis of PSNR values. The obtained results are compared on the basis of PSNR with gradient vector field and big bang optimization. The algorithms are analyzed in terms of performance with respect to accuracy in estimation of tumor region and computational efficiency of the algorithms.

  6. The use of brain CT Scan in craniocerebral trauma with Glasgow coma scale scores of 13 – 15 in Dr. Cipto Mangunkusumo Hospital 1999-2001

    OpenAIRE

    Jofizal Jannis

    2004-01-01

    There is still a controversy among the neurologists whether brain CT scan must be performed on the mild head trauma patients. This study was executed to find out the correlation between the brain CT scan image findings and its clinical impairment among the mild head trauma patients with Glasgow coma scale (GCS) score of 13 to 15. The study was a retrospective study by analyzing the uniform medical records of the head trauma patients hospitalized at the Neurology ward of Dr. Cipto Mangunkusumo...

  7. Quantitative image quality evaluation for cardiac CT reconstructions

    Science.gov (United States)

    Tseng, Hsin-Wu; Fan, Jiahua; Kupinski, Matthew A.; Balhorn, William; Okerlund, Darin R.

    2016-03-01

    Maintaining image quality in the presence of motion is always desirable and challenging in clinical Cardiac CT imaging. Different image-reconstruction algorithms are available on current commercial CT systems that attempt to achieve this goal. It is widely accepted that image-quality assessment should be task-based and involve specific tasks, observers, and associated figures of merits. In this work, we developed an observer model that performed the task of estimating the percentage of plaque in a vessel from CT images. We compared task performance of Cardiac CT image data reconstructed using a conventional FBP reconstruction algorithm and the SnapShot Freeze (SSF) algorithm, each at default and optimal reconstruction cardiac phases. The purpose of this work is to design an approach for quantitative image-quality evaluation of temporal resolution for Cardiac CT systems. To simulate heart motion, a moving coronary type phantom synchronized with an ECG signal was used. Three different percentage plaques embedded in a 3 mm vessel phantom were imaged multiple times under motion free, 60 bpm, and 80 bpm heart rates. Static (motion free) images of this phantom were taken as reference images for image template generation. Independent ROIs from the 60 bpm and 80 bpm images were generated by vessel tracking. The observer performed estimation tasks using these ROIs. Ensemble mean square error (EMSE) was used as the figure of merit. Results suggest that the quality of SSF images is superior to the quality of FBP images in higher heart-rate scans.

  8. PET/CT imaging of delayed radiation encephalopathy following radiotherapy for nasopharyngeal carcinoma

    Institute of Scientific and Technical Information of China (English)

    WANG Xin-lu; YIN Ji-lin; LI Hua; LI Xiang-dong; QUAN Jiang-tao

    2007-01-01

    Background With the significant improvement in the survival of patients with nasopharyngeal carcinoma (NPC)undergoing radiotherapy and the growing availability of the sophisticated imaging modalities, the number of radiation encephalopathy (RE) cases relating to NPC radiotherapy is increasing. In this study, we investigated the metabolic and density changes of the compromised brain tissues during delayed RE using a positron-emission tomography-computed tomography (PET/CT) to provide clinical evidences for the diagnosis of delayed RE following radiotherapy for NPC.Methods The PET/CT manifestations and the clinical data of 53 pathologically confirmed NPC patients with delayed RE following radical radiotherapy and 15 healthy volunteers were investigated. The standardized uptake values (SUV) of the bilateral temporal lobes, the occipital lobe and the brain stem were measured respectively; and then the metabolic reduction rate of 88 temporal lobes and 13 brain stems were calculated for a statistical comparison between the two groups.Results The earliest case of delayed RE in the investigated patients occurred 1.5 years after radiotherapy. Delayed RE frequently involved the inferior temporal lobe. For patients with delayed RE confirmed by clinical symptoms and imaging findings, PET maintained a 100% coincidence rate with CT; however, in the 25 temporal lobes of the 35 delayed RE patients, PET revealed obvious hypometabolic changes whereas CT displayed normal density. The incidence of brain stem metabolic reductions was 24.5% (13/53) in the investigated patients, including 4 patients with hypometabolic changes shown by PET and negative finding shown by CT. The incidence of granuloma adjacent to the hypometabolic region in the temporal lobe was 12.5% (11/88).Conclusion Delayed RE patients exhibit significant hypometabolic changes in the inferior temporal lobe, captured by PET much earlier than by CT. PET/CT offers a valuable means for the diagnosis of delayed RE in

  9. Mobile CT. Technical aspects of prehospital stroke imaging before intravenous thrombolysis

    International Nuclear Information System (INIS)

    To reduce the time from symptom onset to treatment with tissue plasminogen activator (tPA) in ischemic stroke, an ambulance was equipped with a CT scanner. We analyzed process and image quality of CT scanning during the pilot study regarding image quality and safety issues. The pilot study of a stroke emergency mobile unit (STEMO) ran over a period of 12 weeks on 5 weekdays from 7a. m. to 6:30 p. m. A teleradiological service for the justifying indication and reporting was established. The radiographer was responsible for the performance of the CT scan on the ambulance. 64 cranial CT scans and 1 intracranial CT angiography were performed. We compared times from ambulance alarm to treatment decision (time of last brain scan) with a cohort of 50 consecutive tPA treatments before implementation of STEMO. 62 (95 %) of the 65 scans performed had sufficient quality for reading. Technical quality was not optimal in 45 cases (69 %) mainly caused by suboptimal positioning of patient or eye lense protection. Motion artefacts were observed in 8 exams (12 %). No safety issues occurred for team or patients. 23 patients were treated with thrombolysis. Time from alarm to last CT scan was 18 minutes shorter than in the tPA cohort before STEMO implementation. A teleradiological support for primary stroke imaging by CT on-site is feasible, quality-wise of diagnostic value and has not raised safety issues. (orig.)

  10. Measurement of parapharyngeal space using CT images

    Energy Technology Data Exchange (ETDEWEB)

    Ichimura, Keiichi; Kase, Yasuhiro; Iinuma, Toshitaka (Tokyo Univ. (Japan) Branch Hospital)

    1991-04-01

    Parapharyngeal space can be defined as a potential space surrounded by deglutitional and masticator muscles and their covering, superficial and middle layer of deep cervical fascia. Parapharyngeal space has traditionally been divided by styloid process and fascia of tensor veli palatini muscle (nasopharyngeal level) or fascia of stylopharyngeus muscle (oropharyngeal level) into two compartments, prestyloid and poststyloid spaces. The latter is often called as carotid space. Prestyloid portion exclusively contains fat tissue, which yields hypoabsorption area in CT films and high density area in MRI. In most of papers in radiological journals, the term of parapharyngeal space is regarded as its prestyloid portion which is clearly identified. Axial CT images of 144 patients without any naso- or oropharyngeal lesions were analyzed. Two reference levels of nasopharynx were adopted for the study. The upper level passes through the plane of fossa of Rosenmuller, and the lower reference level transects soft palate. The following parameters of the space were measured; Length and width of the whole space, length and width of prestyloid fatty space, and furthermore, width of pre- and poststyloid space, that were divided by a imaginary line pararell to the axis of the whole space (the upper level); Length and width of the whole space, length of base and height of a triangle of the prestyloid part (the lower level). While parapharyngeal space was symmmetrical in the upper level, the rate of asymmetry amounted to a fourth in the lower level. Prestyloid space was broader than poststyloid one in the upper level. Men were dominant in length of the space in both the upper and the lower level and in length of the base of fatty space in the lower level. There was no difference between any age groups other than in fatty area in the lower level. Teens tended to be narrow, while 60's and older were wide. (author).

  11. Measurement of parapharyngeal space using CT images

    International Nuclear Information System (INIS)

    Parapharyngeal space can be defined as a potential space surrounded by deglutitional and masticator muscles and their covering, superficial and middle layer of deep cervical fascia. Parapharyngeal space has traditionally been divided by styloid process and fascia of tensor veli palatini muscle (nasopharyngeal level) or fascia of stylopharyngeus muscle (oropharyngeal level) into two compartments, prestyloid and poststyloid spaces. The latter is often called as carotid space. Prestyloid portion exclusively contains fat tissue, which yields hypoabsorption area in CT films and high density area in MRI. In most of papers in radiological journals, the term of parapharyngeal space is regarded as its prestyloid portion which is clearly identified. Axial CT images of 144 patients without any naso- or oropharyngeal lesions were analyzed. Two reference levels of nasopharynx were adopted for the study. The upper level passes through the plane of fossa of Rosenmuller, and the lower reference level transects soft palate. The following parameters of the space were measured; Length and width of the whole space, length and width of prestyloid fatty space, and furthermore, width of pre- and poststyloid space, that were divided by a imaginary line pararell to the axis of the whole space (the upper level); Length and width of the whole space, length of base and height of a triangle of the prestyloid part (the lower level). While parapharyngeal space was symmmetrical in the upper level, the rate of asymmetry amounted to a fourth in the lower level. Prestyloid space was broader than poststyloid one in the upper level. Men were dominant in length of the space in both the upper and the lower level and in length of the base of fatty space in the lower level. There was no difference between any age groups other than in fatty area in the lower level. Teens tended to be narrow, while 60's and older were wide. (author)

  12. Brain SPECT imaging in temporal lobe epilepsy

    International Nuclear Information System (INIS)

    Temporal lobe epilepsy is diagnosed by clinical symptoms and signs and by localization of an epileptogenic focus. A brain SPECT study of two patients with temporal lobe epilepsy, using 99mTc-HMPAO, was used to demonstrate a perfusion abnormality in the temporal lobe, while brain CT and MRI were non-contributory. The electroencephalogram, though abnormal, did not localize the diseased area. The potential role of the SPECT study in diagnosis and localization of temporal lobe epilepsy is discussed. (orig.)

  13. An Improved Image Mining Technique For Brain Tumour Classification Using Efficient Classifier

    CERN Document Server

    Rajendran, P

    2010-01-01

    An improved image mining technique for brain tumor classification using pruned association rule with MARI algorithm is presented in this paper. The method proposed makes use of association rule mining technique to classify the CT scan brain images into three categories namely normal, benign and malign. It combines the low level features extracted from images and high level knowledge from specialists. The developed algorithm can assist the physicians for efficient classification with multiple keywords per image to improve the accuracy. The experimental result on prediagnosed database of brain images showed 96 percent and 93 percent sensitivity and accuracy respectively.

  14. A modified VMAT adaptive radiotherapy for nasopharyngeal cancer patients based on CT-CT image fusion

    International Nuclear Information System (INIS)

    To investigate the feasibility and benefits of a modified adaptive radiotherapy (ART) by replanning in the initial CT (iCT) with new contours from a repeat CT (rCT) based on CT-CT image fusion for nasopharyngeal cancer (NPC) patients underwent volumetric modulated arc radiotherapy (VMAT). Nine NPC patients underwent VMAT treatment with a rCT at 23rd fraction were enrolled in this study. Dosimetric differences for replanning VMAT plans in the iCT and in the rCT were compared. Volumetric and dosimetric changes of gross tumor volume (GTV) and organs at risk (OARs) of this modified ART were also investigated. No dosimetric differences between replanning in the iCT and in the rCT were observed. The average volume of GTV decreased from 78.83 ± 38.42 cm3 in the iCT to 71.44 ± 37.46 cm3 in the rCT, but with no significant difference (p = 0.42).The average volume of the left and right parotid decreased from 19.91 ± 4.89 cm3 and 21.58 ± 6.16 cm3 in the iCT to 11.80 ± 2.79 cm3 and 13.29 ± 4.17 cm3 in the rCT (both p < 0.01), respectively. The volume of other OARs did not shrink very much. No significant differences on PTVGTV and PTVCTV coverage were observed for replanning with this modified ART. Compared to the initial plans, the average mean dose of the left and right parotid after re-optimization were decreased by 62.5 cGy (p = 0.05) and 67.3 cGy (p = 0.02), respectively, and the V5 (the volume receiving 5 Gy) of the left and right parotids were decreased by 7.8% (p = 0.01) and 11.2% (p = 0.001), respectively. There was no significant difference on the dose delivered to other OARs. Patients with NPC undergoing VMAT have significant anatomic and dosimetric changes to parotids. Repeat CT as an anatomic changes reference and re-optimization in the iCT based on CT-CT image fusion was accurate enough to identify the volume changes and to ensure safe dose to parotids

  15. SPECT/CT imaging in children with papillary thyroid carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Hwa-Young; Gelfand, Michael J.; Sharp, Susan E. [Cincinnati Children' s Hospital, Department of Radiology, Cincinnati, OH (United States)

    2011-08-15

    SPECT/CT improves localization of single photon-emitting radiopharmaceuticals. To determine the utility of SPECT/CT in children with papillary thyroid carcinoma. 20 SPECT/CT and planar studies were reviewed in 13 children with papillary thyroid carcinoma after total thyroidectomy. Seven studies used I-123 and 13 used I-131, after elevating TSH by T4 deprivation or intramuscular thyrotropin alfa. Eight children had one study and five children had two to four studies. Studies were performed at initial post-total thyroidectomy evaluation, follow-up and after I-131 treatment doses. SPECT/CT was performed with a diagnostic-quality CT unit in 13 studies and a localization-only CT unit in 7. Stimulated thyroglobulin was measured (except in 2 cases with anti-thyroglobulin antibodies). In 13 studies, neck activity was present but poorly localized on planar imaging; all foci of uptake were precisely localized by SPECT/CT. Two additional foci of neck uptake were found on SPECT/CT. SPECT/CT differentiated high neck uptake from facial activity. In six studies (four children), neck uptake was identified as benign by SPECT/CT (three thyroglossal duct remnants, one skin contamination, two by precise anatomical CT localization). In two children, SPECT/CT supported a decision not to treat with I-131. When SPECT/CT was unable to identify focal uptake as benign, stimulated thyroglobulin measurements were valuable. In three of 13 studies with neck uptake, SPECT/CT provided no useful additional information. SPECT/CT precisely localizes neck iodine uptake. In small numbers of patients, treatment is affected. SPECT/CT should be used when available in thyroid carcinoma patients. (orig.)

  16. CT and MR imaging characteristics of infantile hepatic hemangioendothelioma

    International Nuclear Information System (INIS)

    Aim: This study aims to analyze computed tomography (CT) and magnetic resonance (MR) imaging features of infantile hepatic hemangioendotheliomas before and after treatment. Materials and methods: CT and MR examinations of seven infants with biopsy proven hepatic hemangioendotheliomas were retrospectively analyzed. The distribution, number, size, imaging appearance, enhancement pattern and post-treatment changes of the tumors were evaluated. Results: A total of 153 hepatic hemangioendotheliomas were detected on CT (111) and MR (42) imaging. In six infants, 109/111 (98.2%) tumors were hypodense and 2/111 (1.8%) lesions contained calcification on unenhanced CT. On MR imaging, all 42 lesions in one infant were heterogeneously T1-hypointense and T2-hyperintense compared to the normal liver parenchyma. Contrast-enhanced CT and MRI showed peripheral rim (51.6%), uniform (48.4%), fibrillary (33.3%), and nodular (28.8%) contrast enhancement in the hepatic arterial phase. Homogeneous (100%), rim (98.2%) and mixed enhancement patterns were noted in tumors 2.0 cm and 1.0-2.0 cm in diameter respectively in the hepatic arterial phase. In three patients who underwent steroid therapy, follow-up CT examination demonstrated tumor size reduction and increased intra-tumoral calcification in two patients. Conclusion: Infantile hepatic hemangioendotheliomas show some typical imaging features and size-dependent pattern of contrast enhancement on CT and MR imaging, which allow accurate imaging diagnosis and post-treatment evaluation.

  17. A generalized method of converting CT image to PET linear attenuation coefficient distribution in PET/CT imaging

    International Nuclear Information System (INIS)

    The accuracy of attenuation correction in positron emission tomography scanners depends mainly on deriving the reliable 511-keV linear attenuation coefficient distribution in the scanned objects. In the PET/CT system, the linear attenuation distribution is usually obtained from the intensities of the CT image. However, the intensities of the CT image relate to the attenuation of photons in an energy range of 40 keV–140 keV. Before implementing PET attenuation correction, the intensities of CT images must be transformed into the PET 511-keV linear attenuation coefficients. However, the CT scan parameters can affect the effective energy of CT X-ray photons and thus affect the intensities of the CT image. Therefore, for PET/CT attenuation correction, it is crucial to determine the conversion curve with a given set of CT scan parameters and convert the CT image into a PET linear attenuation coefficient distribution. A generalized method is proposed for converting a CT image into a PET linear attenuation coefficient distribution. Instead of some parameter-dependent phantom calibration experiments, the conversion curve is calculated directly by employing the consistency conditions to yield the most consistent attenuation map with the measured PET data. The method is evaluated with phantom experiments and small animal experiments. In phantom studies, the estimated conversion curve fits the true attenuation coefficients accurately, and accurate PET attenuation maps are obtained by the estimated conversion curves and provide nearly the same correction results as the true attenuation map. In small animal studies, a more complicated attenuation distribution of the mouse is obtained successfully to remove the attenuation artifact and improve the PET image contrast efficiently. (condensed matter: electronic structure, electrical, magnetic, and optical properties)

  18. A generalized method of converting CT image to PET linear attenuation coefficient distribution in PET/CT imaging

    Science.gov (United States)

    Wang, Lu; Wu, Li-Wei; Wei, Le; Gao, Juan; Sun, Cui-Li; Chai, Pei; Li, Dao-Wu

    2014-02-01

    The accuracy of attenuation correction in positron emission tomography scanners depends mainly on deriving the reliable 511-keV linear attenuation coefficient distribution in the scanned objects. In the PET/CT system, the linear attenuation distribution is usually obtained from the intensities of the CT image. However, the intensities of the CT image relate to the attenuation of photons in an energy range of 40 keV-140 keV. Before implementing PET attenuation correction, the intensities of CT images must be transformed into the PET 511-keV linear attenuation coefficients. However, the CT scan parameters can affect the effective energy of CT X-ray photons and thus affect the intensities of the CT image. Therefore, for PET/CT attenuation correction, it is crucial to determine the conversion curve with a given set of CT scan parameters and convert the CT image into a PET linear attenuation coefficient distribution. A generalized method is proposed for converting a CT image into a PET linear attenuation coefficient distribution. Instead of some parameter-dependent phantom calibration experiments, the conversion curve is calculated directly by employing the consistency conditions to yield the most consistent attenuation map with the measured PET data. The method is evaluated with phantom experiments and small animal experiments. In phantom studies, the estimated conversion curve fits the true attenuation coefficients accurately, and accurate PET attenuation maps are obtained by the estimated conversion curves and provide nearly the same correction results as the true attenuation map. In small animal studies, a more complicated attenuation distribution of the mouse is obtained successfully to remove the attenuation artifact and improve the PET image contrast efficiently.

  19. Role of F-18 FDG PET/CT imaging in the diagnosis of paraneoplastic neurological syndromes

    Institute of Scientific and Technical Information of China (English)

    Lei Kang; Xiaojie Xu; Hongwei Sun; Rongfu Wang

    2014-01-01

    Paraneoplastic neurological syndromes (PNS) is a series of rare neurologic disorders which happen with an underlying malignancy. It has various clinical symptoms proceding to the diagnosis of tumors. Although the abnormality of anti-neuronal antibodies is suggestive of PNS and tumors, there exist many false positive and false negative cases. The diagnosis of PNS is usualy a chalenge in clinic. Positron emission tomography/computed tomography (PET/CT) imaging is an anatomical and functional fusion imaging method, which provides the whole-body information by single scan. Fluorodeoxy-glucose (FDG) PET/CT imaging can not only detect potential malignant lesions in the whole body, but also assess functional abnormality in the brain. In this review, the mechanism, clinical manifestation, diagnostic procedure and the recent progress of the utility of FDG PET/CT in PNS are introduced respectively.

  20. Development of a 3-dimensional CT using an image intensifier

    International Nuclear Information System (INIS)

    A prototype of three-dimensional CT (Fluoroscopic CT) has been developed using an image intensifier as a two-dimensional X-ray detector. A patient on a rotating table is projected onto an image intensifier by a cone beam of X-ray from the X-ray tube. A total of 390 projection images covering 180 degrees are acquired in a single scan (13 sec) and stored on a digital frame recorder (512 x 256 x 8-bit x 480). The transverse axial images are reconstructed by using the usual CT reconstruction algorithm, while longitudinal section images such as sagittal, coronal, oblique, and panoramic images are obtained by directly back-projecting the filtered projection image onto the sections. The radiation exposure was measured with an ionization chamber, and the exposure of the present fluoroscopic CT is about 10 to 20 times less than that of conventional X-ray CT. A similar monochromatic X-ray CT system has also been developed using synchrotron radiation. Large area parallel X-rays are obtained from a wiggler beam using a silicon crystal with [311] asymmetric reflection. By taking two images above and below iodine K-absorption edge (33.17 keV), iodine image is obtained. (author)

  1. CT images of infantile viral encephalitis

    International Nuclear Information System (INIS)

    Cranial CT scanning was undertaken in 40 patients with infantile viral encephalitis seen from 1977 to 1983. According to the pathogenic viruses, abnormal CT findings were detected most frequently in cases of herpes simplex encephalitis (HSE), followed by non-eruptive viral encephalitis, measles encephalitis, and rubella encephalitis in that order, which coincided well with neurological prognosis. Although CT findings lay within a normal range in cases of measles encephalitis, except a case in which cerebral ventricle was slightly dilated, the degree of consciousness disturbance was unfavorable and it persisted long. This revealed that there is no distinct correlation between the degree of consciousness disturbance and CT findings. Normal CT findings were detected in 13% of patients aged less than 5 years and 76.5% of patients aged 5 years or more. In many patients who had an attack of viral encephalitis at the age of 5 years or more, epileptic seizures occurred frequently, even though CT findings were normal. (Namekawa, K.)

  2. Ultrasonography Fused with PET-CT Hybrid Imaging

    DEFF Research Database (Denmark)

    Udesen, Jesper; Ewertsen, Caroline; Gran, Fredrik;

    2011-01-01

    We present a method with fusion of images of three modalities 18F-FDG PET, CT, and 3-D ultrasound (US) applied to imaging of the anal canal and the rectum. To obtain comparable geometries in the three imaging modalities, a plexiglas rod, with the same dimensions as the US transducer, is placed in...... the anal canal prior to the PET-CT examination. The method is based on manual co-registration of PET-CT images and 3-D US images. The three-modality imaging of the rectum-anal canal may become useful as a supplement to conventional imaging in the external radiation therapy in the treatment of anal....... Three-modality imaging may also be used in certain other diagnostic or therapeutic fields....

  3. Computer-aided diagnosis of pneumoconiosis in CT images

    International Nuclear Information System (INIS)

    The classification of chest radiographs on pneumoconiosis has been widely used for the purpose of epidemiologic study and mass surveillance in Japan. We are developing an automated method for determining a class of rounded opacities of pneumoconiosis in CT images. The image processing computer is NEXUS 6400 equipped with pipeline processor, and the CT equipment is TCT-900S. CT images are analyzed by the image processing computer. The processes include a smoothing by median filter, a transformation into binary thresholded picture, rejections of frame area (chest wall and mediastinum), labeling of lung field small pictures, identifying pneumoconiotic small rounded opacities and calculations of sizes and profusions. In our investigation by this system, the diagnostic accuracy was 85.7% dealing with 14 CT images. (author)

  4. Automated Selection of Uniform Regions for CT Image Quality Detection

    CERN Document Server

    Naeemi, Maitham D; Roychodhury, Sohini

    2016-01-01

    CT images are widely used in pathology detection and follow-up treatment procedures. Accurate identification of pathological features requires diagnostic quality CT images with minimal noise and artifact variation. In this work, a novel Fourier-transform based metric for image quality (IQ) estimation is presented that correlates to additive CT image noise. In the proposed method, two windowed CT image subset regions are analyzed together to identify the extent of variation in the corresponding Fourier-domain spectrum. The two square windows are chosen such that their center pixels coincide and one window is a subset of the other. The Fourier-domain spectral difference between these two sub-sampled windows is then used to isolate spatial regions-of-interest (ROI) with low signal variation (ROI-LV) and high signal variation (ROI-HV), respectively. Finally, the spatial variance ($var$), standard deviation ($std$), coefficient of variance ($cov$) and the fraction of abdominal ROI pixels in ROI-LV ($\

  5. Bacterial brain abscesses: prognostic value of an imaging severity index

    International Nuclear Information System (INIS)

    Aim: To assess the correlation between imaging findings [computed tomography (CT) or magnetic resonance imaging (MRI)] and neurological status before and after the treatment of bacterial brain abscesses. Materials and methods: CT and MRI images of 96 patients with brain abscesses were retrospectively evaluated in terms of the number, location and size of lesions, and the presence and extent of perilesional oedema and midline shift. An imaging severity index (ISI) based on these different radiological parameters was calculated. Initial Glasgow Coma Scale (GCS) scores and ISI were assessed and the prognostic value of these two indices was calculated. The Pearson correlation test, Mann-Whitney test, Chi-square test, receiver-operating characteristic (ROC) analysis, together with comparison of ROC analyses and Fisher's exact test were used. Results: There was a negative correlation between ISI and the initial GCS values: ISI increased as the GCS score decreased, indicating an inverse relationship (r = -0.51, p < 0.0001). There was a significant difference between the ISI and GCS scores of patients with an adverse event compared with patients with good recovery. Outcome was significantly worse in patients with initial ISI over the calculated cut-off values of 8 points or GCS scores under the cut-off value of 13 points. Conclusion: ISI is a useful prognostic indicator for bacterial brain abscess patients and correlates strongly with the patient outcome for all parameters studied. ISI score had a better prognostic value than GCS

  6. Recurrent neuroblastoma: the role of CT and alternative imaging tests

    International Nuclear Information System (INIS)

    One hundred twelve CT scans of 52 patients who were receiving treatment for neuroblastoma were reviewed for accuracy, and findings were correlated with data obtained from other imaging tests, physical examinations, laboratory tests, biopsies, surgery, and long-term clinical follow-up. CT was the most sensitive imaging test for tumor recurrence (85% detection rate), and it was also the most versatile in the ability to define recurrent disease in the retroperitoneum, liver, cranium, mediastinum, lymph nodes, and skeleton. All 30 tumor recurrences were detected by the combination of CT, bone-marrow biopsy, and selected spot radiographs at the sites of pain. CT was accurate and clinically useful both for assessing tumor response to therapy and for predicting findings at second look surgery (accuracy, 94%). CT is relatiely cost effective by substituting for a more expensive but less accurate combination of competitive imaging studies

  7. Imaging and PET-CT evaluation of Gi tract cancers

    International Nuclear Information System (INIS)

    Imaging plays a pivotal role in the management of G.I. tract cancers for diagnosis, characterization, locoregional staging, metastatic work-up and follow-up during and after curative or palliative treatment. The imaging protocols should be optimized and reproducible because of their impact on therapy. Thoracic, abdominal and pelvic CT is the cornerstone of the imaging work-up, optimized and reproducible because of their impact on therapy. Thoracic, abdominal and pelvic CT is the cornerstone of the imaging work-up, optimized and tailored to the specific G.I. segment involved, requiring good G.I. tract distension. Image interpretation of native axial and reformatted multiplanar images is routinely performed. In specific cases, additional targeted imaging with the US or MRI or whole body imaging with PET/CT or MRI may be valuable. PET/CT is a complement to morphological imaging. PET allows detection of lesions otherwise undetected on morphological imaging, usually due to poor contrast with surrounding tissues, and characterization of known lesions. PET/CT is best used as an integral part of a comprehensive imaging work-up. Radiologist and nuclear medicine specialists provide complementary information. each must be familiar with the clinical questions at hand and related stakes, and advantages and limitations of each modality to optimize treatment as part of a multidisciplinary management approach. (authors)

  8. A case of burn encephalopathy with reversible brain atrophy on brain computed tomography (CT)

    International Nuclear Information System (INIS)

    We present an interesting case of burn encephalopathy. The patient is a three-year-old girl with second to third degree and 30 % scald burn. She developed central nervous symptom on the second day with high fever and systemic convulsions and was transferred to our clinic on the third day from a local hospital. Her level of consciousness was 30 to 100 (3-3-9 formula) and she developed extra-pyramidal involuntary movement; these neurological signs persisted untill 66th day when she spoke for the first time since admission. Her EEG showed diffuse brain dysfunction and CT showed marked brain atrophy. She began to improve after around 50 days systematically as well as neurologically and was discharged after four months. EEG, CT findings and neurological signs were normal 1.5 years later. We could not find a case of reversible brain atrophy in the reports on burn encephalopathy or other neurological disorders except for the cases of long-term steroid administration on autoimmune diseases or ACTH therapy on infantile spasm. In our case, the reversible brain atrophy might be caused by the rise of endogenous steroid under burn stress, or transient malfunction of cerebro-spinal fluid absorption, or some other causes. (author)

  9. Imaging findings of the brain abnormalities in acute lymphoblastic leukemia of children during and after treatment

    International Nuclear Information System (INIS)

    We evaluated the imaging abnormalities of the brain observed during and after treatment of acute childhood lymphoblastic leukemia. The study group consisted of 30 patients (male : female=19 : 11 ; mean age, 64 months) with acute childhood lymphoblastic leukemia during the previous ten-year period who had undergone prophylaxis of the central nervous system. Irrespective of the CNS symptoms, base-line study of the brain involving CT and follow-up CT or MRI was undertaken more than once. We retrospectively evaluated the imaging findings, methods of treatment, associated CNS symptoms, and the interval between diagnosis and the time at which brain abnormalities were revealed by imaging studies. In 15 (50% ; male : female=9 : 6 ; mean age, 77 months) of 30 patients, brain abnormalities that included brain atrophy (n=9), cerebral infarctions (n=4), intracranial hemorrhage (n=1), mineralizing microangiopathy (n=2), and periventricular leukomalacia (n=3) were seen on follow-up CT or MR images. In four of nine patients with brain atrophy, imaging abnormalities such as periventricular leukomalacia (n=2), infarction (n=1) and microangiopathy (n=1) were demonstrated. Fourteen of the 15 patients underwent similar treatment ; the one excluded had leukemic cells in the CSF. Six patients had CNS symptoms. In the 15 patients with abnormal brain imaging findings, the interval between diagnosis and the demonstration of brain abnormalities was between one month and four years. After the cessation of treatment, imaging abnormalities remained in all patients except one with brain atrophy. Various imaging abnormalities of the brain may be seen during and after the treatment of acute childhood lymphoblastic leukemia and persist for a long time. In children with this condition, the assessment of brain abnormalities requires follow-up study of the brain

  10. Imaging findings of the brain abnormalities in acute lymphoblastic leukemia of children during and after treatment

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Kyung Joo; Lee, Seung Rho; Park, Dong Woo; Joo, Kyung Bin; Kim, Jang Wook; Hahm, Chang Kok; Kim, Ki Joong; Lee, Hahng [College of Medicine, Hanyang Univ., Seoul (Korea, Republic of)

    2001-09-01

    We evaluated the imaging abnormalities of the brain observed during and after treatment of acute childhood lymphoblastic leukemia. The study group consisted of 30 patients (male : female=19 : 11 ; mean age, 64 months) with acute childhood lymphoblastic leukemia during the previous ten-year period who had undergone prophylaxis of the central nervous system. Irrespective of the CNS symptoms, base-line study of the brain involving CT and follow-up CT or MRI was undertaken more than once. We retrospectively evaluated the imaging findings, methods of treatment, associated CNS symptoms, and the interval between diagnosis and the time at which brain abnormalities were revealed by imaging studies. In 15 (50% ; male : female=9 : 6 ; mean age, 77 months) of 30 patients, brain abnormalities that included brain atrophy (n=9), cerebral infarctions (n=4), intracranial hemorrhage (n=1), mineralizing microangiopathy (n=2), and periventricular leukomalacia (n=3) were seen on follow-up CT or MR images. In four of nine patients with brain atrophy, imaging abnormalities such as periventricular leukomalacia (n=2), infarction (n=1) and microangiopathy (n=1) were demonstrated. Fourteen of the 15 patients underwent similar treatment ; the one excluded had leukemic cells in the CSF. Six patients had CNS symptoms. In the 15 patients with abnormal brain imaging findings, the interval between diagnosis and the demonstration of brain abnormalities was between one month and four years. After the cessation of treatment, imaging abnormalities remained in all patients except one with brain atrophy. Various imaging abnormalities of the brain may be seen during and after the treatment of acute childhood lymphoblastic leukemia and persist for a long time. In children with this condition, the assessment of brain abnormalities requires follow-up study of the brain.

  11. Brain (18)F-FDG, (18)F-Florbetaben PET/CT, (123)I-FP-CIT SPECT and Cardiac (123)I-MIBG Imaging for Diagnosis of a "Cerebral Type" of Lewy Body Disease.

    Science.gov (United States)

    Van Der Gucht, Axel; Cleret de Langavant, Laurent; Bélissant, Ophélie; Rabu, Corentin; Cottereau, Anne-Ségolène; Evangelista, Eva; Chalaye, Julia; Bonnot-Lours, Sophie; Fénelon, Gilles; Itti, Emmanuel

    2016-09-01

    A 67-year-old man was referred for fluctuating neuropsychiatric symptoms, featuring depression, delirious episodes, recurrent visual hallucinations and catatonic syndrome associated with cognitive decline. No parkinsonism was found clinically even under neuroleptic treatment. (18)F-FDG PET/CT showed hypometabolism in the posterior associative cortex including the occipital cortex, suggesting Lewy body dementia, but (123)I-FP-CIT SPECT was normal and cardiac (123)I-MIBG imaging showed no signs of sympathetic denervation. Alzheimer's disease was excluded by a normal (18)F-florbetaben PET/CT. This report suggests a rare case of α-synucleinopathy without brainstem involvement, referred to as "cerebral type" of Lewy body disease. PMID:27540431

  12. Radiation exposure distribution in patients undergoing CT brain scans

    International Nuclear Information System (INIS)

    The distribution of surface exposures in patients undergoing single and multiple computerized tomographic brain scans with Hitachi CT-W500 was measured by LiF(Mg, Ti) thermoluminescent dosimetry. It was found that there was no significant difference in the sufrace exposures from different scanning slices. However, the exposure doses at different scanning angles around the head were different significantly. The reference point of the maximum surface exposure was at the temporal part of the head. the maximum surface exposure was at 1.65 x 10-3 C·kg-1 while the average exposure was 1.55 x 10-3 C·kg-1. The ratio of the average dose resulting from nine scans to that from a single scan was 1.3, and the surface exposure contribution of scattered radiation was computed. At the same time the radiation doses to eyes, thyroid, chest and gonads of patiens at corresponding position were also measured and were compared with those from CT cranial scans in children and skull radiographic procedures respectively

  13. FDG PET/CT imaging of lung tumor

    International Nuclear Information System (INIS)

    PET/CT imaging combines PET for functional information and CT for morphological information in a single examination, and has shown how the initial staging with lung cancer. [18F]fluoro-deoxy-glucose (FDG) PET/CT imaging has a higher diagnostic accuracy for lung cancer except so-called bronchioloalveolar carcinoma and acute inflammatory lesion such as tuberculosis, pneumonia etc, compared with the conventional diagnostic modalities. FDG PET/CT imaging can demonstrate unexpected sites of mediastinal lymph node metastases (N factor), distant metastases (M factor) in initial staging and influence treatment plans for lung cancer. Furthermore, the grade of FDG uptake on PET/CT predicts prognosis of lung cancer and evaluates tumor response to treatment. Recurrences or metastases of lung cancer, and pleural disease can be detected correctly on FDG PET/CT. It is important that interpreting physicians understand the role of FDG PET/CT in staging, assessing of treatment and observing after therapy on the multidisciplinary managements of lung cancer. The clinical applications of PET/CT are still evolving, and future researches will determine the precise role that combined metabolic and morphological imaging has to play in the management of patients with lung cancer. (author)

  14. Holographic observation of magnetic resonance image CT of intracranial tumors

    International Nuclear Information System (INIS)

    In 1975, we developed a new method of 3-dimensional observation of CT pictures using Gabor's holography principle. In this study, we are reporting our experience with the multi-tomogram holography using magnetic resonance image CT in order to reconstruct 3-dimensional viewing of the central nervous system and intracranial lesions. (J.P.N.)

  15. Order of CT stroke protocol (CTA before or after CTP): impact on image quality

    Energy Technology Data Exchange (ETDEWEB)

    Dorn, Franziska [Technical University, Department of Radiology, Klinikum rechts der Isar, Munich (Germany); University Hospital of Cologne, Department of Radiology and Neuroradiology, Cologne (Germany); Institut fuer Radiologie, Klinikum rechts der Isar der Technischen Universitaet Muenchen, Munich (Germany); Liebig, Thomas [University Hospital of Cologne, Department of Radiology and Neuroradiology, Cologne (Germany); Muenzel, Daniela; Meier, Reinhard; Rummeny, Ernst J.; Huber, Armin [Technical University, Department of Radiology, Klinikum rechts der Isar, Munich (Germany); Poppert, Holger [Technical University, Department of Neurology, Klinikum rechts der Isar, Munich (Germany)

    2012-02-15

    The purpose of this study was to determine the appropriate order of CT angiography and CT perfusion in a multimodal stroke CT protocol. Forty patients with clinical suspicion of an acute cerebral infarct underwent non-enhanced CT (NECT), CT angiography (CTA), and CT perfusion (CTP). Twenty examinations were performed with CTP before CTA (group 1) and 20 in reversed order (group 2). Mean densities were determined at baseline and peak enhancement of CTP, as well as on source images of CTA in defined brain regions. Contrast of extra-/intracranial arteries and veins was rated according to a 5-point scale (1 = excellent, 5 = poor). CT-perfusion maps were assessed by determining the mean transit time (MTT), cerebral blood flow (CBF), and blood volume (CBV) in identical regions. Mean densities between both groups were not significantly different for CTA and CTP at peak enhancement. At CTP baseline, mean densities between groups 1 and 2 were different for all points except for GM and WM. There was no significant difference between both groups for the mean delta (the difference between baseline and peak enhancement), as well as for mean MTT, CBV, and CBF. Subjective evaluation of the CTA quality revealed no difference between both protocols, except for the extracranial venous contrast, which was less severe in group 2. Reversal of CT stroke protocol had no significant influence on quantitative parameters of CTP. Subjective quality of extracranial venous contrast was rated to be superior when CTA was performed before CTP. (orig.)

  16. SU-E-T-416: VMAT Dose Calculations Using Cone Beam CT Images: A Preliminary Study

    Energy Technology Data Exchange (ETDEWEB)

    Yu, S; Sehgal, V; Kuo, J; Daroui, P; Ramsinghani, N; Al-Ghazi, M [University of California, Orange, CA (United States)

    2014-06-01

    Purpose: Cone beam CT (CBCT) images have been used routinely for patient positioning throughout the treatment course. However, use of CBCT for dose calculation is still investigational. The purpose of this study is to assess the utility of CBCT images for Volumetric Modulated Arc Therapy (VMAT) plan dose calculation. Methods: A CATPHAN 504 phantom (The Phantom Laboratory, Salem, NY) was used to compare the dosimetric and geometric accuracy between conventional CT and CBCT (in both full and half fan modes). Hounsfield units (HU) profiles at different density areas were evaluated. A C shape target that surrounds a central avoidance structure was created and a VMAT plan was generated on the CT images and copied to the CBCT phantom images. Patient studies included three brain patients, and one head and neck (H'N) patient. VMAT plans generated on the patients treatment planning CT was applied to CBCT images obtained during the first treatment. Isodose distributions and dosevolume- histograms (DVHs) were compared. Results: For the phantom study, the HU difference between CT and CBCT is within 100 (maximum 96 HU for Teflon CBCT images in full fan mode). The impact of these differences on the calculated dose distributions was clinically insignificant. In both phantom and patient studies, target DVHs based on CBCT images were in excellent agreement with those based on planning CT images. Mean, Median, near minimum (D98%), and near maximum (D2%) doses agreed within 0-2.5%. A slightly larger discrepancy is observed in the patient studies compared to that seen in the phantom study, (0-1% vs. 0 - 2.5%). Conclusion: CBCT images can be used to accurately predict dosimetric results, without any HU correction. It is feasible to use CBCT to evaluate the actual dose delivered at each fraction. The dosimetric consequences resulting from tumor response and patient geometry changes could be monitored.

  17. SU-E-T-416: VMAT Dose Calculations Using Cone Beam CT Images: A Preliminary Study

    International Nuclear Information System (INIS)

    Purpose: Cone beam CT (CBCT) images have been used routinely for patient positioning throughout the treatment course. However, use of CBCT for dose calculation is still investigational. The purpose of this study is to assess the utility of CBCT images for Volumetric Modulated Arc Therapy (VMAT) plan dose calculation. Methods: A CATPHAN 504 phantom (The Phantom Laboratory, Salem, NY) was used to compare the dosimetric and geometric accuracy between conventional CT and CBCT (in both full and half fan modes). Hounsfield units (HU) profiles at different density areas were evaluated. A C shape target that surrounds a central avoidance structure was created and a VMAT plan was generated on the CT images and copied to the CBCT phantom images. Patient studies included three brain patients, and one head and neck (H'N) patient. VMAT plans generated on the patients treatment planning CT was applied to CBCT images obtained during the first treatment. Isodose distributions and dosevolume- histograms (DVHs) were compared. Results: For the phantom study, the HU difference between CT and CBCT is within 100 (maximum 96 HU for Teflon CBCT images in full fan mode). The impact of these differences on the calculated dose distributions was clinically insignificant. In both phantom and patient studies, target DVHs based on CBCT images were in excellent agreement with those based on planning CT images. Mean, Median, near minimum (D98%), and near maximum (D2%) doses agreed within 0-2.5%. A slightly larger discrepancy is observed in the patient studies compared to that seen in the phantom study, (0-1% vs. 0 - 2.5%). Conclusion: CBCT images can be used to accurately predict dosimetric results, without any HU correction. It is feasible to use CBCT to evaluate the actual dose delivered at each fraction. The dosimetric consequences resulting from tumor response and patient geometry changes could be monitored

  18. Differential MRI Diagnosis Between Brain Abscess and Necrotic or Cystic Brain Tumors Using Diffusion Weighted Images

    Directory of Open Access Journals (Sweden)

    Zinat Miabi

    2009-01-01

    Full Text Available "nIntroduction: Differentiating brain abscesses from cystic or necrotic tumors by CT or MR imaging can be difficult. Difficulties in the diagnosis of intracranial abscess are mainly due to the combination of often unspecified clinical findings and similarities in the morphologic appearance of some intracranial mass lesions, such as cystic gliomas, metastases, and brain abscesses. Diffusion-weighted imaging provides a way to evaluate the diffusion properties of water molecules in tissue and has been used for diseases such as ischemia, tumors, epilepsy, and white matter disorders. The goal of this study was to evaluate the diagnostic utility of diffusion MRI to differentiate between brain abscesses and necrotic or cystic brain tumors. "nMaterials and Methods: MRI was performed in 17 patients (12 men and five women; age range, 19–74 years [mean, 55 years] with necrotic lesions and MR imaging evidence of ring-shaped enhancement after the injection of contrast material .In addition to standard MR sequences diffusion weighted MRI with apparent coefficient (ADC maps. "nResults: Eleven patients had tumors, and six had pyogenic abscesses. The tumors were glioblastomas (five patients, anaplastic astrocytoma (three patients, metastases (three patients, and primary malignancy, including lung (2 and breast (1 cancer. Surgical or stereotactic biopsies were obtained, and histologic studies were performed in all except one case (case 5. In the cases of abscess, bacteriologic analysis was also conducted. None of these lesions appeared hemorrhagic on T1-weighted images. "nConclusion: Diffusion-weighted imaging is useful for differentiating brain abscess from cystic or necrotic brain tumor, which is often difficult with conventional MR imaging. Diffusion-weighted imaging is useful as an additional imaging technique for establishing the differential diagnosis between brain abscesses and cystic or necrotic brain tumors. It requires less imaging time and is more

  19. Volumetric CT-images improve testing of radiological image interpretation skills

    International Nuclear Information System (INIS)

    Rationale and objectives: Current radiology practice increasingly involves interpretation of volumetric data sets. In contrast, most radiology tests still contain only 2D images. We introduced a new testing tool that allows for stack viewing of volumetric images in our undergraduate radiology program. We hypothesized that tests with volumetric CT-images enhance test quality, in comparison with traditional completely 2D image-based tests, because they might better reflect required skills for clinical practice. Materials and methods: Two groups of medical students (n = 139; n = 143), trained with 2D and volumetric CT-images, took a digital radiology test in two versions (A and B), each containing both 2D and volumetric CT-image questions. In a questionnaire, they were asked to comment on the representativeness for clinical practice, difficulty and user-friendliness of the test questions and testing program. Students’ test scores and reliabilities, measured with Cronbach's alpha, of 2D and volumetric CT-image tests were compared. Results: Estimated reliabilities (Cronbach's alphas) were higher for volumetric CT-image scores (version A: .51 and version B: .54), than for 2D CT-image scores (version A: .24 and version B: .37). Participants found volumetric CT-image tests more representative of clinical practice, and considered them to be less difficult than volumetric CT-image questions. However, in one version (A), volumetric CT-image scores (M 80.9, SD 14.8) were significantly lower than 2D CT-image scores (M 88.4, SD 10.4) (p < .001). The volumetric CT-image testing program was considered user-friendly. Conclusion: This study shows that volumetric image questions can be successfully integrated in students’ radiology testing. Results suggests that the inclusion of volumetric CT-images might improve the quality of radiology tests by positively impacting perceived representativeness for clinical practice and increasing reliability of the test

  20. Volumetric CT-images improve testing of radiological image interpretation skills

    Energy Technology Data Exchange (ETDEWEB)

    Ravesloot, Cécile J., E-mail: C.J.Ravesloot@umcutrecht.nl [Radiology Department at University Medical Center Utrecht, Heidelberglaan 100, 3508 GA Utrecht, Room E01.132 (Netherlands); Schaaf, Marieke F. van der, E-mail: M.F.vanderSchaaf@uu.nl [Department of Pedagogical and Educational Sciences at Utrecht University, Heidelberglaan 1, 3584 CS Utrecht (Netherlands); Schaik, Jan P.J. van, E-mail: J.P.J.vanSchaik@umcutrecht.nl [Radiology Department at University Medical Center Utrecht, Heidelberglaan 100, 3508 GA Utrecht, Room E01.132 (Netherlands); Cate, Olle Th.J. ten, E-mail: T.J.tenCate@umcutrecht.nl [Center for Research and Development of Education at University Medical Center Utrecht, Heidelberglaan 100, 3508 GA Utrecht (Netherlands); Gijp, Anouk van der, E-mail: A.vanderGijp-2@umcutrecht.nl [Radiology Department at University Medical Center Utrecht, Heidelberglaan 100, 3508 GA Utrecht, Room E01.132 (Netherlands); Mol, Christian P., E-mail: C.Mol@umcutrecht.nl [Image Sciences Institute at University Medical Center Utrecht, Heidelberglaan 100, 3508 GA Utrecht (Netherlands); Vincken, Koen L., E-mail: K.Vincken@umcutrecht.nl [Image Sciences Institute at University Medical Center Utrecht, Heidelberglaan 100, 3508 GA Utrecht (Netherlands)

    2015-05-15

    Rationale and objectives: Current radiology practice increasingly involves interpretation of volumetric data sets. In contrast, most radiology tests still contain only 2D images. We introduced a new testing tool that allows for stack viewing of volumetric images in our undergraduate radiology program. We hypothesized that tests with volumetric CT-images enhance test quality, in comparison with traditional completely 2D image-based tests, because they might better reflect required skills for clinical practice. Materials and methods: Two groups of medical students (n = 139; n = 143), trained with 2D and volumetric CT-images, took a digital radiology test in two versions (A and B), each containing both 2D and volumetric CT-image questions. In a questionnaire, they were asked to comment on the representativeness for clinical practice, difficulty and user-friendliness of the test questions and testing program. Students’ test scores and reliabilities, measured with Cronbach's alpha, of 2D and volumetric CT-image tests were compared. Results: Estimated reliabilities (Cronbach's alphas) were higher for volumetric CT-image scores (version A: .51 and version B: .54), than for 2D CT-image scores (version A: .24 and version B: .37). Participants found volumetric CT-image tests more representative of clinical practice, and considered them to be less difficult than volumetric CT-image questions. However, in one version (A), volumetric CT-image scores (M 80.9, SD 14.8) were significantly lower than 2D CT-image scores (M 88.4, SD 10.4) (p < .001). The volumetric CT-image testing program was considered user-friendly. Conclusion: This study shows that volumetric image questions can be successfully integrated in students’ radiology testing. Results suggests that the inclusion of volumetric CT-images might improve the quality of radiology tests by positively impacting perceived representativeness for clinical practice and increasing reliability of the test.

  1. Unified wavelet and gaussian filtering for segmentation of CT images; application in segmentation of bone in pelvic CT images

    OpenAIRE

    2009-01-01

    Background The analysis of pelvic CT scans is a crucial step for detecting and assessing the severity of Traumatic Pelvic Injuries. Automating the processing of pelvic CT scans could impact decision accuracy, decrease the time for decision making, and reduce health care cost. This paper discusses a method to automate the segmentation of bone from pelvic CT images. Accurate segmentation of bone is very important for developing an automated assisted-decision support system for Traumatic Pelvic ...

  2. Ultrasonography Fused with PET-CT Hybrid Imaging

    DEFF Research Database (Denmark)

    Udesen, Jesper; Ewertsen, Caroline; Gran, Fredrik; Fogh Christensen, Anders; Kjaer-Kristoffersen, Flemming; Engelholm, Svend Aage; Jensen, Jørgen Arendt; Nielsen, Michael Bachmann

    2011-01-01

    the anal canal prior to the PET-CT examination. The method is based on manual co-registration of PET-CT images and 3-D US images. The three-modality imaging of the rectum-anal canal may become useful as a supplement to conventional imaging in the external radiation therapy in the treatment of anal......We present a method with fusion of images of three modalities 18F-FDG PET, CT, and 3-D ultrasound (US) applied to imaging of the anal canal and the rectum. To obtain comparable geometries in the three imaging modalities, a plexiglas rod, with the same dimensions as the US transducer, is placed in...... cancer, where the precise delineation of a tumor is crucial to avoid damage from radiation therapy to the healthy tissue surrounding it. The technique is still in a phase of development, and the demands for integration different company software systems are significant before commercial application...

  3. Imaging fusion (SPECT/CT) in degenerative disease of spine

    International Nuclear Information System (INIS)

    Full text: Objective: To determine the utility of Fusion Imaging SPECT/CT in degenerative pathology of the spine and to establish the impact of the use of fusion imaging in spinal pain due to degenerative changes of the spine. Materials and methods: 44 Patients (M=21, F=23) average age of 63 years and with degenerative pathology of spine were sent to Diagnosis Imaging department in FSFB. Bone scintigraphy (SPECT), CT of spine (cervical: 30%, Lumbar 70%) and fusion imaging were performed in all of them. Bone scintigraphy was carried out in a gamma camera Siemens Diacam double head attached to ESOFT computer. The images were acquired in matrix 128 x 128, 20 seg/imag, 64 images. CT of spine was performed same day or two days after in Helycoidal Siemens somatom emotion CT. The fusion was done in a Dicom workstation in sagital, axial and coronal reconstruction. The findings were evaluated by 2 Nuclear Medicine physicians and 2 radiologists of the staff of FSFB in an independent way. Results: Bone scan (SPECT) and CT of 44 patients were evaluated. CT showed facet joint osteoarthrities in 27 (61.3%) patients, uncovertebral joint arthrosis in 7 (15.9%), bulging disc in 9(20.4%), spinal nucleus lesion in 7(15.9%), osteophytes in 9 (20.4%), spinal foraminal stenosis in 7 (15.9%), spondylolysis/spondylolisthesis in 4 (9%). Bone scan showed facet joint osteoarthrities in 29 (65.9%), uncovertebral joint arthrosis in 4 (9%), osteophytes in 9 (20.4%) and normal 3 (6.8%). The imaging fusion showed coincidence findings (main lesion in CT with high uptake in scintigraphy) in 34 patients (77.2%) and no coincidence in 10 (22.8%). In 15 (34.09%) patients the fusion provided additional information. The analysis of the findings of CT and SPECT showed similar results in most of the cases and the fusion didn't provide additional information but it allowed to confirm the findings but when the findings didn't match where the CT showed several findings and SPECT only one area with high uptake

  4. Correlative Imaging in a Patient with Cystic Thymoma: CT, MR and PET/CT Comparison

    International Nuclear Information System (INIS)

    Cystic thymoma is a rare variant of thymic neoplasm characterized by almost complete cystic degeneration with mixed internal structure. We describe a case of a 60 year-old woman with a cystic thymoma studied with advanced tomographic imaging stydies. CT, MRI and PET/CT with 18F-FDG were performed; volumetric CT and MRI images provided better anatomic evaluation for pre-operative assessment, while PET/CT was helpful for lesion characterization based on 18F-FDG uptake. Although imaging studies are mandatory for pre-operative evaluation of cystic thymoma, final diagnosis still remains surgical. A 60-year-old woman with recent chest pain and no history of previous disease was admitted to our departement to investigate the result of a previous chest X-ray that showed bilateral mediastinal enlargement; for this purpose, enhanced chest CT scan was performed using a 64-rows scanner (Toshiba, Aquilion 64, Japan) before and after intravenous bolus administration of iodinated non ionic contrast agent; CT images demonstrated the presence of a large mediastinal mass (11×8 cm) located in the anterior mediastinum who extended from the anonymous vein to the cardio-phrenic space, compressing the left atrium and causing medium lobe atelectasis; bilateral pleural effusion was also present. In conclusion, correlative imaging plays a foundamental role for the diagnostic evaluation of patient with cystic thymoma. In particular, volumetric CT and MRI studies can provide better anatomic informations regarding internal structure and local tumor spread for pre-operative assessment. Conversely, metabolic imaging using 18F-FDG PET/CT is helpful for lesion characterization differentiating benign from malignant lesion on the basis of intense tracer uptake. The role of PET/MRI is still under investigation. However, final diagnosis still remains surgical even though imaging studies are mandatory for pre-operative patient management

  5. Image dissimilarity-based quantification of lung disease from CT

    DEFF Research Database (Denmark)

    Sørensen, Lauge; Loog, Marco; Lo, Pechin;

    2010-01-01

    In this paper, we propose to classify medical images using dissimilarities computed between collections of regions of interest. The images are mapped into a dissimilarity space using an image dissimilarity measure, and a standard vector space-based classifier is applied in this space. The...... computed tomography (CT) images, achieving an area under the receiver operating characteristic curve of 0.817. This is significantly better compared to combining individual region classifications into an overall image classification, and compared to common computerized quantitative measures in pulmonary CT....

  6. Low-dose CT scan screening for lung cancer: comparison of images and radiation doses between low-dose CT and follow-up standard diagnostic CT

    OpenAIRE

    ONO, KOJI; Hiraoka, Toru; Ono, Asami; Komatsu, Eiji; Shigenaga, Takehiko; Takaki, Hajime; Maeda, Toru; Ogusu, Hiroyuki; Yoshida, Shintaro; Fukushima, Kiyoyasu; Kai, Michiaki

    2013-01-01

    Objectives This study aim to compare image quality and radiation doses between low-dose CT and follow-up standard diagnostic CT for lung cancer screening. Methods In a single medical institution, 19 subjects who had been screened for lung cancer by low-dose CT before going through follow-up standard diagnostic CT were randomly selected. Both CT image sets for all subjects were independently evaluated by five specialized physicians. Results There were no significant differences between low-dos...

  7. Development of a realistic, dynamic digital brain phantom for CT perfusion validation

    Science.gov (United States)

    Divel, Sarah E.; Segars, W. Paul; Christensen, Soren; Wintermark, Max; Lansberg, Maarten G.; Pelc, Norbert J.

    2016-03-01

    Physicians rely on CT Perfusion (CTP) images and quantitative image data, including cerebral blood flow, cerebral blood volume, and bolus arrival delay, to diagnose and treat stroke patients. However, the quantification of these metrics may vary depending on the computational method used. Therefore, we have developed a dynamic and realistic digital brain phantom upon which CTP scans can be simulated based on a set of ground truth scenarios. Building upon the previously developed 4D extended cardiac-torso (XCAT) phantom containing a highly detailed brain model, this work consisted of expanding the intricate vasculature by semi-automatically segmenting existing MRA data and fitting nonuniform rational B-spline surfaces to the new vessels. Using time attenuation curves input by the user as reference, the contrast enhancement in the vessels changes dynamically. At each time point, the iodine concentration in the arteries and veins is calculated from the curves and the material composition of the blood changes to reflect the expected values. CatSim, a CT system simulator, generates simulated data sets of this dynamic digital phantom which can be further analyzed to validate CTP studies and post-processing methods. The development of this dynamic and realistic digital phantom provides a valuable resource with which current uncertainties and controversies surrounding the quantitative computations generated from CTP data can be examined and resolved.

  8. CT and MR Unilateral Brain Features Secondary to Nonketotic Hyperglycemia Presenting as Hemichorea-Hemiballism

    Directory of Open Access Journals (Sweden)

    Víctor Manuel Suárez-Vega

    2016-01-01

    Full Text Available Hemichorea-hemiballism is an unusual hyperkinetic movement disorder characterized by continuous involuntary movements of an entire limb or both limbs on one side of the body. The acute onset of this disorder occurs with an insult in contralateral basal ganglia. Ischemic events represent the most common cause. Nonketotic hyperglycemia comes in second place. Nonketotic hyperglycemic hemichorea-hemiballism (NHH is a rare cause of unilateral brain abnormalities on imaging studies confined to basal ganglia (mainly putaminal region as well as caudate nucleus. Subtle hyperdensity in striatal region can be found on CT studies whereas brain MR imaging typically shows T1 hyperintensity and T2 hypointensity in the basal ganglia contralateral to the movements. Diagnosis is based on both glucose levels and neuroimaging findings. Elevated blood glucose and hemoglobin A1c levels occur with poorly controlled diabetes. In this case report, our aim is to present neuroimaging CT and MR unilateral findings in an elderly woman secondary to nonketotic hyperglycemia presenting as hemichorea-hemiballism.

  9. Patient-specific CT dose determination from CT images using Monte Carlo simulations

    Science.gov (United States)

    Liang, Qing

    Radiation dose from computed tomography (CT) has become a public concern with the increasing application of CT as a diagnostic modality, which has generated a demand for patient-specific CT dose determinations. This thesis work aims to provide a clinically applicable Monte-Carlo-based CT dose calculation tool based on patient CT images. The source spectrum was simulated based on half-value layer measurements. Analytical calculations along with the measured flux distribution were used to estimate the bowtie-filter geometry. Relative source output at different points in a cylindrical phantom was measured and compared with Monte Carlo simulations to verify the determined spectrum and bowtie-filter geometry. Sensitivity tests were designed with four spectra with the same kVp and different half-value layers, and showed that the relative output at different locations in a phantom is sensitive to different beam qualities. An mAs-to-dose conversion factor was determined with in-air measurements using an Exradin A1SL ionization chamber. Longitudinal dose profiles were measured with thermoluminescent dosimeters (TLDs) and compared with the Monte-Carlo-simulated dose profiles to verify the mAs-to-dose conversion factor. Using only the CT images to perform Monte Carlo simulations would cause dose underestimation due to the lack of a scatter region. This scenario was demonstrated with a cylindrical phantom study. Four different image extrapolation methods from the existing CT images and the Scout images were proposed. The results show that performing image extrapolation beyond the scan region improves the dose calculation accuracy under both step-shoot scan mode and helical scan mode. Two clinical studies were designed and comparisons were performed between the current CT dose metrics and the Monte-Carlo-based organ dose determination techniques proposed in this work. The results showed that the current CT dosimetry failed to show dose differences between patients with the same

  10. 'Ready-access' CT imaging for an orthopaedic trauma clinic.

    LENUS (Irish Health Repository)

    Cawley, D

    2011-03-01

    \\'Ready-Access\\' to CT imaging facilities in Orthopaedic Trauma Clinics is not a standard facility. This facility has been available at the regional trauma unit, in Merlin Park Hospital, Galway for the past four years. We reviewed the use of this facility over a 2-year period when 100 patients had CT scans as part of their trauma clinic assessment. The rate of CT scan per clinic was 0.6. The mean waiting time for a CT scan was 30 minutes. 20 (20%) new fractures were confirmed, 33 (33%) fractures were out-ruled, 25 (25%) fractures demonstrated additional information and 8 (8%) had additional fractures. 20 (20%) patients were discharged and 12 (12%) patients were admitted as a result of the CT scan. It adds little time and cost to CT scanning lists.

  11. An iterative CT reconstruction algorithm for fast fluid flow imaging

    OpenAIRE

    Eyndhoven, van, G.L.; Batenburg, K. Joost; Kazantsev, Daniil; Van Nieuwenhove, Vincent; Lee, Peter D.; Dobson, Katherine J.; Sijbers, Jan

    2015-01-01

    Abstract: The study of fluid flow through solid matter by computed tomography (CT) imaging has many applications, ranging from petroleum and aquifer engineering to biomedical, manufacturing, and environmental research. To avoid motion artifacts, current experiments are often limited to slow fluid flow dynamics. This severely limits the applicability of the technique. In this paper, a new iterative CT reconstruction algorithm for improved a temporal/spatial resolution in the imaging of fluid f...

  12. Clinical applications of SPECT/CT in imaging the extremities

    Energy Technology Data Exchange (ETDEWEB)

    Huellner, Martin W. [University Hospital Zurich, Department of Medical Radiology, Division of Nuclear Medicine, Zurich (Switzerland); Strobel, Klaus [Lucerne Cantonal Hospital, Department of Nuclear Medicine and Radiology, Lucerne (Switzerland)

    2014-05-15

    Today, SPECT/CT is increasingly used and available in the majority of larger nuclear medicine departments. Several applications of SPECT/CT as a supplement to or replacement for traditional conventional bone scintigraphy have been established in recent years. SPECT/CT of the upper and lower extremities is valuable in many conditions with abnormal bone turnover due to trauma, inflammation, infection, degeneration or tumour. SPECT/CT is often used in patients if conventional radiographs are insufficient, if MR image quality is impaired due to metal implants or in patients with contraindications to MR. In complex joints such as those in the foot and wrist, SPECT/CT provides exact anatomical correlation of pathological uptake. In many cases SPECT increases the sensitivity and CT the specificity of the study, increasing confidence in the final diagnosis compared to planar images alone. The CT protocol should be adapted to the clinical question and may vary from very low-dose (e.g. attenuation correction only), to low-dose for anatomical correlation, to normal-dose protocols enabling precise anatomical resolution. The aim of this review is to give an overview of SPECT/CT imaging of the extremities with a focus on the hand and wrist, knee and foot, and for evaluation of patients after joint arthroplasty. (orig.)

  13. A new method for robust organ positioning in CT images

    NARCIS (Netherlands)

    Vik, T.; Bystrov, D.; Schadewaldt, N.; Schulz, H.; Peters, J.

    2012-01-01

    A robust initialization is the key to any successful segmentation process in medical images. For CT images, initialization ischallenging because the quality, appearance, content and field-of-view of the images are highly variable, and, furthermore, the user tolerance to errors in clinical applicatio

  14. Castleman disease of the neck: CT and MR imaging findings

    International Nuclear Information System (INIS)

    Objective: To characterize the computed tomography (CT) and magnetic resonance imaging (MRI) findings of Castleman disease of the neck. Methods: The imaging findings of 21 patients with Castleman disease of the neck were reviewed retrospectively. Of the 21 patients, 16 underwent unenhanced and contrast-enhanced CT scans; 5 underwent unenhanced and contrast-enhanced MRI scans. Results: The unenhanced CT images showed isolated or multiple well-defined homogenous mild hypodensity lesions in fifteen cases, and a heterogeneous nodule with central areas of mild hypodensity in one case. Calcification was not observed in any of the patients. In five patients, MR T1-weighted images revealed well-defined, homogeneous isointense or mild hyperintense lesions to the muscle; T2-weighted images showed these as intermediate hyperintense. Sixteen cases showed intermediate to marked homogeneous enhancement on contrast-enhanced CT or MR T1-weighted images. Of the other five cases that underwent double-phase CT scans, four showed mild or intermediate heterogeneous enhancement at the arterial phase, and homogeneous intermediate or marked enhancement at the venous phase; the remaining case showed mild and intermediate ring-enhancement with a central non-enhanced area at the arterial and venous phases, respectively. Conclusion: Castleman disease of the neck can be characterized as solitary or multiple well-defined, mild hypodensity or homogeneous intense lesions on plain CT/MR scans, and demonstrates intermediate and marked enhancement on contrast-enhanced CT/MR scans. On double-phase CT scans, Castleman disease often demonstrates mild enhancement at the arterial phase, and gradually uniform enhancement at venous phase. Double-phase enhanced CT or MRI may help to differentiate Castleman disease from other diseases

  15. Interobserver variations in gross tumor volume delineation of brain tumors on computed tomography and impact of magnetic resonance imaging

    International Nuclear Information System (INIS)

    Purpose: (1) To assess the interobserver variability of brain tumor delineation on computed tomography (CT). (2) To assess the impact of the addition of magnetic resonance imaging (MRI) information. Methods: Nine physicians were asked to delineate the gross tumor volume (GTV) of five patients with supratentorial inoperable brain tumors on CT scans and 2 weeks (or more) later on MRIs. The delineations were performed on a computer screen. During delineation on MRI, the registered CT images (without delineation) were displayed on the screen (MRI+CT). Results: A high interobserver variability in GTV delineation on CT is found: the ratio of the largest to the smallest defined volumes varies for the five patients by factors of resp. 2.8, 1.8, 1.8, 1.9 and 1.7. The interobserver variability is as large on MRI+CT as on CT alone (ratio largest/smallest volume: 2.4, 1.7, 1.9, 2.7 and 1.5). Volumes delineated on MRI+CT (mean: 69.6 cm3) are larger than on CT alone (mean: 59.5 cm3). Residual volumes (volume delineated on one image modality but not on the other) are >0 for CT alone and for MRI+CT. Conclusions: A large interobserver variability in GTV delineation of brain tumors is demonstrated. The addition of MRI to CT does not reduce interobserver variability. GTVs delineated on MRI+CT are larger than on CT alone, but some volumes are delineated on CT and not on MRI. Therefore, a combination of the two image modalities is recommended for brain tumor delineation for treatment planning

  16. X-Ray Scatter Correction on Soft Tissue Images for Portable Cone Beam CT.

    Science.gov (United States)

    Aootaphao, Sorapong; Thongvigitmanee, Saowapak S; Rajruangrabin, Jartuwat; Thanasupsombat, Chalinee; Srivongsa, Tanapon; Thajchayapong, Pairash

    2016-01-01

    Soft tissue images from portable cone beam computed tomography (CBCT) scanners can be used for diagnosis and detection of tumor, cancer, intracerebral hemorrhage, and so forth. Due to large field of view, X-ray scattering which is the main cause of artifacts degrades image quality, such as cupping artifacts, CT number inaccuracy, and low contrast, especially on soft tissue images. In this work, we propose the X-ray scatter correction method for improving soft tissue images. The X-ray scatter correction scheme to estimate X-ray scatter signals is based on the deconvolution technique using the maximum likelihood estimation maximization (MLEM) method. The scatter kernels are obtained by simulating the PMMA sheet on the Monte Carlo simulation (MCS) software. In the experiment, we used the QRM phantom to quantitatively compare with fan-beam CT (FBCT) data in terms of CT number values, contrast to noise ratio, cupping artifacts, and low contrast detectability. Moreover, the PH3 angiography phantom was also used to mimic human soft tissues in the brain. The reconstructed images with our proposed scatter correction show significant improvement on image quality. Thus the proposed scatter correction technique has high potential to detect soft tissues in the brain. PMID:27022608

  17. X-Ray Scatter Correction on Soft Tissue Images for Portable Cone Beam CT

    Directory of Open Access Journals (Sweden)

    Sorapong Aootaphao

    2016-01-01

    Full Text Available Soft tissue images from portable cone beam computed tomography (CBCT scanners can be used for diagnosis and detection of tumor, cancer, intracerebral hemorrhage, and so forth. Due to large field of view, X-ray scattering which is the main cause of artifacts degrades image quality, such as cupping artifacts, CT number inaccuracy, and low contrast, especially on soft tissue images. In this work, we propose the X-ray scatter correction method for improving soft tissue images. The X-ray scatter correction scheme to estimate X-ray scatter signals is based on the deconvolution technique using the maximum likelihood estimation maximization (MLEM method. The scatter kernels are obtained by simulating the PMMA sheet on the Monte Carlo simulation (MCS software. In the experiment, we used the QRM phantom to quantitatively compare with fan-beam CT (FBCT data in terms of CT number values, contrast to noise ratio, cupping artifacts, and low contrast detectability. Moreover, the PH3 angiography phantom was also used to mimic human soft tissues in the brain. The reconstructed images with our proposed scatter correction show significant improvement on image quality. Thus the proposed scatter correction technique has high potential to detect soft tissues in the brain.

  18. Image quality assessment for CT used on small animals

    Science.gov (United States)

    Cisneros, Isabela Paredes; Agulles-Pedrós, Luis

    2016-07-01

    Image acquisition on a CT scanner is nowadays necessary in almost any kind of medical study. Its purpose, to produce anatomical images with the best achievable quality, implies the highest diagnostic radiation exposure to patients. Image quality can be measured quantitatively based on parameters such as noise, uniformity and resolution. This measure allows the determination of optimal parameters of operation for the scanner in order to get the best diagnostic image. A human Phillips CT scanner is the first one minded for veterinary-use exclusively in Colombia. The aim of this study was to measure the CT image quality parameters using an acrylic phantom and then, using the computational tool MatLab, determine these parameters as a function of current value and window of visualization, in order to reduce dose delivery by keeping the appropriate image quality.

  19. The assessment of intracranial bleeding with virtual unenhanced imaging by means of dual-energy CT angiography

    Energy Technology Data Exchange (ETDEWEB)

    Ferda, Jiri; Novak, Milan; Mirka, Hynek; Baxa, Jan; Ferdova, Eva; Bednarova, Alena; Kreuzberg, Boris [Charles University Teaching Hospital Plzen, Radiodiagnostic Clinic (Czech Republic); Flohr, Thomas; Schmidt, Bernhard; Klotz, Ernst [Siemens Healthcare, Computed Tomography (Germany)

    2009-10-15

    The purpose of this study was to assess virtual unenhanced brain computed tomography (CT) images obtained by dual-energy CT angiography (CTA) for the detection of intracranial bleeding. In total, 25 patients were included in the study (average age 53.2 years, range 25-75 years, 14 male, 11 female), all with intracranial bleeding on unenhanced brain CT and who underwent additional CTA performed on a dual-source CT in a dual-energy acquisition mode. The two X-ray tubes were operated at 140 and 80 kV, respectively. Data were analyzed using dual-energy evaluation software. Virtual unenhanced images were calculated by removing the relative iodine content from each voxel. The virtual unenhanced images were evaluated by a radiologist blinded to the findings of the conventional images related to the presence of intracranial bleeding. The image quality and contrast-to-noise ratio (CNR) between bleeding and brain tissue were assessed. The virtual image quality was found to be sufficient in 96%. The agreement in detection of intracranial bleeding on virtual and conventional unenhanced images reached 96% in per-lesion analysis and 100% in per-patient analysis. The averaged CNR reached 2.63 in virtual unenhanced images and 3.27 in conventional. Virtual unenhanced images are sufficient for the detection of intracranial bleeding. (orig.)

  20. Brain MR imaging in dietarily treated phenylketonuria

    Energy Technology Data Exchange (ETDEWEB)

    Breysem, L. [Dept. of Radiology, University Hospitals, Leuven (Belgium); Smet, M.H. [Dept. of Radiology, University Hospitals, Leuven (Belgium); Johannik, K. [Dept. of Radiology, University Hospitals, Leuven (Belgium); Hecke, P. van [Dept. of Radiology, University Hospitals, Leuven (Belgium); Francois, B. [L. Willems Inst., Diepenbeek (Belgium); Wilms, G. [Dept. of Radiology, University Hospitals, Leuven (Belgium); Bosmans, H. [Dept. of Radiology, University Hospitals, Leuven (Belgium); Marchal, G. [Dept. of Radiology, University Hospitals, Leuven (Belgium); Jaeken, J. [Dept. of Pediatrics, University Hospitals, Leuven (Belgium); Demaerel, P. [Dept. of Radiology, University Hospitals, Leuven (Belgium)

    1994-08-01

    Magnetic resonance imaging is the most efficient imaging modality to evaluate brain gray and white matter of patients with metabolic diseases. The main purpose of our study was to investigate the relation between brain MRI abnormalities and the phenylalanine (phe) and tyrosine (tyr) blood levels in 38 phenylketonuria (PKU) patients. Increased periventricular white matter intensity on T2-weighted brain images was the only pathologic finding in 24 patients. Brain MRI abnormalities were scored (4) and correlated with the individual mean phe and phe/tyr levels during 1 year preceding MR examination and with phe tolerance. The residual activity of phenylalanine hydroxylase was defined for each patient by an oral phe tolerance. The appearance of MRI abnormalities on brain T2-weighted images correlates with a threshold mean phe level (averaged over the year preceding the examination). (orig.)

  1. Deformable planning CT to cone-beam CT image registration in head-and-neck cancer

    International Nuclear Information System (INIS)

    Purpose: The purpose of this work was to implement and validate a deformable CT to cone-beam computed tomography (CBCT) image registration method in head-and-neck cancer to eventually facilitate automatic target delineation on CBCT. Methods: Twelve head-and-neck cancer patients underwent a planning CT and weekly CBCT during the 5-7 week treatment period. The 12 planning CT images (moving images) of these patients were registered to their weekly CBCT images (fixed images) via the symmetric force Demons algorithm and using a multiresolution scheme. Histogram matching was used to compensate for the intensity difference between the two types of images. Using nine known anatomic points as registration targets, the accuracy of the registration was evaluated using the target registration error (TRE). In addition, region-of-interest (ROI) contours drawn on the planning CT were morphed to the CBCT images and the volume overlap index (VOI) between registered contours and manually delineated contours was evaluated. Results: The mean TRE value of the nine target points was less than 3.0 mm, the slice thickness of the planning CT. Of the 369 target points evaluated for registration accuracy, the average TRE value was 2.6±0.6 mm. The mean TRE for bony tissue targets was 2.4±0.2 mm, while the mean TRE for soft tissue targets was 2.8±0.2 mm. The average VOI between the registered and manually delineated ROI contours was 76.2±4.6%, which is consistent with that reported in previous studies. Conclusions: The authors have implemented and validated a deformable image registration method to register planning CT images to weekly CBCT images in head-and-neck cancer cases. The accuracy of the TRE values suggests that they can be used as a promising tool for automatic target delineation on CBCT.

  2. Early CT signs of progressive hemorrhagic injury following acute traumatic brain injury

    Energy Technology Data Exchange (ETDEWEB)

    Tong, Wu-song; Zheng, Ping; Xu, Jun-fa; Guo, Yi-jun; Zeng, Jing-song; Yang, Wen-jin; Li, Gao-yi; He, Bin; Yu, Hui [Pudong New Area People' s Hospital, Department of Neurosurgery, Shanghai (China)

    2011-05-15

    Since progressive hemorrhagic injury (PHI) was introduced in neurosurgical literatures, several studies have been performed, the results of which have influenced doctors but do not define guidelines for the best treatment of PHI. PHI may be confirmed by a serial computerized tomography (CT) scan, and it has been shown to be associated with a fivefold increase in the risk of clinical worsening and is a significant cause of morbidity and mortality as well. So, early detection of PHI is practically important in a clinical situation. To analyze the early CT signs of progressive hemorrhagic injury following acute traumatic brain injury (TBI) and explore their clinical significances, PHI was confirmed by comparing the first and repeated CT scans. Data were analyzed and compared including times from injury to the first CT and signs of the early CT scan. Logistic regression analysis was used to show the risk factors related to PHI. A cohort of 630 TBI patients was evaluated, and there were 189 (30%) patients who suffered from PHI. For patients with their first CT scan obtained as early as 2 h post-injury, there were 116 (77.25%) cases who suffered from PHI. The differences between PHIs and non-PHIs were significant in the initial CT scans showing fracture, subarachnoid hemorrhage (SAH), brain contusion, epidural hematoma (EDH), subdural hematoma (SDH), and multiple hematoma as well as the times from injury to the first CT scan (P < 0.01). Logistic regression analysis showed that early CT scans (EDH, SDH, SAH, fracture, and brain contusion) were predictors of PHI (P < 0.01). For patients with the first CT scan obtained as early as 2 h post-injury, a follow-up CT scan should be performed promptly. If the initial CT scan shows SAH, brain contusion, and primary hematoma with brain swelling, an earlier and dynamic CT scan should be performed for detection of PHI as early as possible and the medical intervention would be enforced in time. (orig.)

  3. Early CT signs of progressive hemorrhagic injury following acute traumatic brain injury

    International Nuclear Information System (INIS)

    Since progressive hemorrhagic injury (PHI) was introduced in neurosurgical literatures, several studies have been performed, the results of which have influenced doctors but do not define guidelines for the best treatment of PHI. PHI may be confirmed by a serial computerized tomography (CT) scan, and it has been shown to be associated with a fivefold increase in the risk of clinical worsening and is a significant cause of morbidity and mortality as well. So, early detection of PHI is practically important in a clinical situation. To analyze the early CT signs of progressive hemorrhagic injury following acute traumatic brain injury (TBI) and explore their clinical significances, PHI was confirmed by comparing the first and repeated CT scans. Data were analyzed and compared including times from injury to the first CT and signs of the early CT scan. Logistic regression analysis was used to show the risk factors related to PHI. A cohort of 630 TBI patients was evaluated, and there were 189 (30%) patients who suffered from PHI. For patients with their first CT scan obtained as early as 2 h post-injury, there were 116 (77.25%) cases who suffered from PHI. The differences between PHIs and non-PHIs were significant in the initial CT scans showing fracture, subarachnoid hemorrhage (SAH), brain contusion, epidural hematoma (EDH), subdural hematoma (SDH), and multiple hematoma as well as the times from injury to the first CT scan (P < 0.01). Logistic regression analysis showed that early CT scans (EDH, SDH, SAH, fracture, and brain contusion) were predictors of PHI (P < 0.01). For patients with the first CT scan obtained as early as 2 h post-injury, a follow-up CT scan should be performed promptly. If the initial CT scan shows SAH, brain contusion, and primary hematoma with brain swelling, an earlier and dynamic CT scan should be performed for detection of PHI as early as possible and the medical intervention would be enforced in time. (orig.)

  4. PET and PET/CT for imaging of prostate cancer

    International Nuclear Information System (INIS)

    This review article provides an overview of the current literature data regarding the value of PET and PET/CT for imaging of prostate cancer. Most widely used PET tracers for prostate cancer imaging are 11C-acetate and 11C- or 18F-labeled choline. Available literature data on the performance of PET and PET/CT in the detection of the primary malignancy as well as local or distant metastases are presented and discussed. In addition, our own preliminary results regarding the diagnostic efficacy of 11C-choline PET and PET/CT in 43 patients with suspected prostate cancer are provided. The prevalence of prostate cancer in this patient sample was 55.8%. PET and PET/CT showed a sensitivity of 88% with a specificity of 63% in the detection of the primary prostate cancer. The sensitivity in the detection of metastatic spread was 77% and no false-positives were found. The possible value and limitations of combined PET/CT systems when compared to stand alone PET scanners are discussed. PET and PET/CT is at present the single imaging modality providing functional information not only regarding the primary malignancy but also its metastases. This unique feature distinguishes PET from MRI complemented with magnetic resonance spectroscopy - a competing procedure. Our own results as well as the still limited literature data suggest, that PET and PET/CT may prove to be useful methods for imaging of prostate cancer. (orig.)

  5. Image registration in the brain: a test of clinical accuracy

    International Nuclear Information System (INIS)

    (p=.250). Overall, the expansion required by 3D registration software was significan tly less than that required by either the CT or simulated films method. Conclusion: For multimodality imaging data to be used in treatment planning of brain tumors it must be 3D-registered with the planning CT. Hand drawing the tumor onto the planning CT or directly onto the simulation film will lead to clinically significant targeting errors

  6. CT ventilation functional image-based IMRT treatment plans are comparable to SPECT ventilation functional image-based plans

    OpenAIRE

    Kida, S.; Bal, M; Kabus, S; Negandar, M; Shan, X.; Jr, LBW; Keall, PJ; Yamamoto, T.

    2016-01-01

    To investigate the hypothesis that CT ventilation functional image-based IMRT plans designed to avoid irradiating highly-functional lung regions are comparable to single-photon emission CT (SPECT) ventilation functional image-based plans.Three IMRT plans were created for eight thoracic cancer patients using: (1) CT ventilation functional images, (2) SPECT ventilation functional images, and (3) anatomic images (no functional images). CT ventilation images were created by deformable image regis...

  7. Gallium-68 ethylenediamine tetraacetic acid (EDTA) imaging of brain tumors by positron tomography

    International Nuclear Information System (INIS)

    While noncontrast CT demonstrates the effects of brain tumors, such as regions surrounding the tumors with low CT numbers, contrast is often required to show the tumor itself. Unfortunately, contrast may cause seizures in 9-15% of patients with brain metastases. Contrast enters the tumor region because of absence of the blood-brain barrier (BBB). Chelates have been used in planar nuclear imaging to study BBB integrity, but have not been used widely in position tomography. The authors carried out positron tomography (PET) with Ga-68 EDTA in 22 patients with suspected or proven brain tumors. In l3/22, the lesions were detected equally well by contract CT and PET. In 3/22 the lesions were more clearly visualized with PET than contrast CT. In 1 case, there as a more extensive abnormality on PET than on contract CT. In 2 post-operating patients, the presence of tumor was detected by contrast CT and PET, but interference from surgical clips obscured the CT but not the PET images. Indications for positron tomography with Ga-68 EDTA include allergy to contrast media, history of seizures with contrast media, or interfering opacities such as surgical clips or calcifications. An important characteristic of Ga-68 EDTA is that it is easily eluted from a long lived Ge-68 generator. Furthermore, GA-68 EDTA can be used to quantify BBB integrity with the appropriate modelling, e.g. as in steroid therapy

  8. [Imaging of brain changes in chronic pain].

    Science.gov (United States)

    Vartiainen, Nuutti; Forss, Nina

    2014-01-01

    Modern methods of brain imaging have enabled objective measurements of functional and structural brain changes associated with chronic pain conditions. According to recent investigations, chronic pain is not only associated with abnormally strong or prolonged activity of regions processing acute pain, but also with activation of brain networks that are characteristic for each pain state, changes in cortical remodeling, as well as local reduction of grey matter in several regions of the brain. Brain changes associated with chronic pain facilitate the understanding of mechanisms of various chronic pain conditions. PMID:25211820

  9. Low-dose spiral CT: applicability to paediatric chest imaging

    International Nuclear Information System (INIS)

    Background. Spiral CT of the chest is an imaging technique with unequivocal indications and proven higher sensitivity and specificity than conventional chest X-rays. However, particularly in children, attempts should be made to reduce radiation exposure to a minimum. Objective. To evaluate whether a low-dose technique in spiral CT scanning results in adequate diagnostic information. Materials and methods. In a prospective study, 27 children (range 3 weeks to 14 years, mean 7 years) underwent a low-dose CT examination of the chest for various indications. The tube energy was 12.5 mAs (n = 5), 25 mAs (n = 17), 50 mAs (n = 3), or 75 mAs (n = 2) per slice. Two radiologists evaluated, in consensus, the CT scans with respect to their diagnostic value and comparison was made with 20 standard-dose chest CT examinations of adults (175 mAs per slice, mean age 56 years) with respect to technical image quality (noise and artefacts). In a second part of the study, dose measurements were carried out by means of exposing thermoluminescent dosimeters attached to a water/air phantom simulating a child's chest. Results. All low-dose CT scans were of diagnostic image quality and no additional studies were necessary. The average image noise was significantly higher than in standard-dose CT examinations (SD 39.5 compared with 12.5 for unenhanced soft tissue, P < 0.01), but did not hinder accurate diagnosis. Artefacts were exclusively due to patient motion. Radiation exposure per slice was approx. 4 mGy at 25 mAs and 34 mGy at 250 mAs, regardless of slice thickness. Conclusions. For all indications in paediatric CT scanning of the chest, low-dose technique provides adequate image quality without loss of diagnostic information. The radiation exposure is approximately 5-20 % of a standard-dose CT. (orig.)

  10. 2D geometric measurement method based on industrial CT images

    International Nuclear Information System (INIS)

    To achieve the non-destructive measurement of the internal structure of the objects, a kind of automatic dimension measuring method using industrial computed tomography (ICT) images was presented based on a threshold of edge extraction. First, a pretreatment of CT images was carried out Then, the best threshold segmentation method was used to extract edge, based on this work the automatic geometry measurement of the CT images was achieved. The results show that geometric measurement of images reaches to a certain degree of accuracy and meet the basic needs of accuracy and repeatability. Simultaneously this method may reduce the influence of artifacts. (authors)

  11. Mobile CT. Technical aspects of prehospital stroke imaging before intravenous thrombolysis; CT im Notarztwagen. Technische Aspekte der praehospitalen radiologischen Schlaganfalldiagnostik vor systemischer Thrombolyse

    Energy Technology Data Exchange (ETDEWEB)

    Gierhake, Daniel; Villringer, K.; Fiebach, J.B. [Charite - Universitaetsmedizin Berlin (Germany). Center for Stroke Research Berlin (CSB); Weber, J.E.; Audebert, H.J. [Charite - Universitaetsmedizin Berlin (Germany). Center for Stroke Research Berlin (CSB); Charite - Universitaetsmedizin Berlin (Germany). Klinik fuer Neurologie; Ebinger, M. [Charite - Universitaetsmedizin Berlin (Germany). Center for Stroke Research Berlin (CSB); Charite - Universitaetsmedizin Berlin (Germany). Klinik und Hochschulambulanz fuer Neurologie

    2013-01-15

    To reduce the time from symptom onset to treatment with tissue plasminogen activator (tPA) in ischemic stroke, an ambulance was equipped with a CT scanner. We analyzed process and image quality of CT scanning during the pilot study regarding image quality and safety issues. The pilot study of a stroke emergency mobile unit (STEMO) ran over a period of 12 weeks on 5 weekdays from 7a. m. to 6:30 p. m. A teleradiological service for the justifying indication and reporting was established. The radiographer was responsible for the performance of the CT scan on the ambulance. 64 cranial CT scans and 1 intracranial CT angiography were performed. We compared times from ambulance alarm to treatment decision (time of last brain scan) with a cohort of 50 consecutive tPA treatments before implementation of STEMO. 62 (95 %) of the 65 scans performed had sufficient quality for reading. Technical quality was not optimal in 45 cases (69 %) mainly caused by suboptimal positioning of patient or eye lense protection. Motion artefacts were observed in 8 exams (12 %). No safety issues occurred for team or patients. 23 patients were treated with thrombolysis. Time from alarm to last CT scan was 18 minutes shorter than in the tPA cohort before STEMO implementation. A teleradiological support for primary stroke imaging by CT on-site is feasible, quality-wise of diagnostic value and has not raised safety issues. (orig.)

  12. A comparison study of PET, NMR, and CT imaging in cerebral ischemia

    International Nuclear Information System (INIS)

    Whether ischemia without infarction produces recognizable changes in relaxation times of ischemic but viable brain is an important, unresolved issue. Therefore, a study was initiated of patients with cerebral ischemia, using positron emission tomography (PET), NMR, and computed tomography (CT) to compare and contrast the pathophysiologic information provided by each and to study the issue of whether cerebral ischemia without infarction can be appreciated by proton NMR imaging. Here the initial results are reported. 4 refs.; 2 figs.; 1 table

  13. PET/CT Imaging in Mouse Models of Myocardial Ischemia

    Directory of Open Access Journals (Sweden)

    Sara Gargiulo

    2012-01-01

    Full Text Available Different species have been used to reproduce myocardial infarction models but in the last years mice became the animals of choice for the analysis of several diseases, due to their short life cycle and the possibility of genetic manipulation. Many techniques are currently used for cardiovascular imaging in mice, including X-ray computed tomography (CT, high-resolution ultrasound, magnetic resonance imaging, and nuclear medicine procedures. Cardiac positron emission tomography (PET allows to examine noninvasively, on a molecular level and with high sensitivity, regional changes in myocardial perfusion, metabolism, apoptosis, inflammation, and gene expression or to measure changes in anatomical and functional parameters in heart diseases. Currently hybrid PET/CT scanners for small laboratory animals are available, where CT adds high-resolution anatomical information. This paper reviews mouse models of myocardial infarction and discusses the applications of dedicated PET/CT systems technology, including animal preparation, anesthesia, radiotracers, and images postprocessing.

  14. Comparison of image quality in head CT studies with different dose-reduction strategies

    DEFF Research Database (Denmark)

    Johansen, Jeppe; Nielsen, Rikke; Fink-Jensen, Vibeke;

    account to a considerable radiation dose as many patients undergo repeated studies. Therefore, various dose-reduction strategies are applied such as automated tube current and voltage modulation and recently different iterative reconstruction algorithms. However, the trade-off of all dose......-reduction maneuvers is reduction of image quality due to image noise or artifacts. The aim of our study was therefore to find the best diagnostic images with lowest possible dose. We present results of dose- and image quality optimizing strategies of brain CT examinations at our institution. We compare sequential...... and helical head CT with different tube current and voltage settings including protocols with and without automated dose modulation and assess quality of noise reduction in conjunction with iterative reconstruction algorithms....

  15. Skeletal scintigraphy and SPECT/CT in orthopedic imaging

    International Nuclear Information System (INIS)

    Multi-modality imaging with SPECT-CT in orthopaedics combines the excellent sensitivity of scintigraphy with the morphological information of CT as a key for specific interpretation of findings in bone scans. The result is an imaging modality with the clear potential to prove of value even in a competitive setting dominated by MRI, and to significantly add to diagnostic imaging in orthopaedics. SPECT-CT is of great value in the diagnostic evaluation after fractures, and - in contrast to MRI - it is well suited for imaging in patients with osteosyntheses and metallic implants. In sports medicine, SPECT-CT allows for a sensitive and specific detection of osseous stress reactions before morphological changes become detectable by CT or MRI. In patients with osseous pain syndromes, actively evolving degenerative changes as a cause of pain can be identified and accurately localized. Further, particularly prospective diagnostic studies providing comparative data are needed to strengthen the position of nuclear imaging in orthopaedics and sports medicine and to help implementing SPECT/CT in diagnostic algorithms. (orig.)

  16. Image Processing Technique for Brain Abnormality Detection

    Directory of Open Access Journals (Sweden)

    Ashraf Anwar

    2013-02-01

    Full Text Available Medical imaging is expensive and very much sophisticated because of proprietary software and expert personalities. This paper introduces an inexpensive, user friendly general-purpose image processing tool and visualization program specifically designed in MATLAB to detect much of the brain disorders as early as possible. The application provides clinical and quantitative analysis of medical images. Minute structural difference of brain gradually results in major disorders such as schizophrenia, Epilepsy, inherited speech and language disorder, Alzheimer's dementia etc. Here the main focusing is given to diagnose the disease related to the brain and its psychic nature (Alzheimer’s disease.

  17. Pulmonary ventilation and perfusion imaging with dual-energy CT

    Energy Technology Data Exchange (ETDEWEB)

    Thieme, Sven F. [Klinikum Grosshadern, Department of Clinical Radiology, Ludwig Maximilians University, Muenchen (Germany); Klinikum Grosshadern, Institut fuer Klinische Radiologie, LMU Muenchen, Muenchen (Germany); Hoegl, Sandra; Fisahn, Juergen; Irlbeck, Michael [Klinikum Grosshadern, Department of Anesthesiology, Ludwig Maximilians University, Muenchen (Germany); Nikolaou, Konstantin; Maxien, Daniel; Reiser, Maximilian F.; Becker, Christoph R.; Johnson, Thorsten R.C. [Klinikum Grosshadern, Department of Clinical Radiology, Ludwig Maximilians University, Muenchen (Germany)

    2010-12-15

    To evaluate the feasibility of dual-energy CT (DECT) ventilation imaging in combination with DE perfusion mapping for a comprehensive assessment of ventilation, perfusion, morphology and structure of the pulmonary parenchyma. Two dual-energy CT acquisitions for xenon-enhanced ventilation and iodine-enhanced perfusion mapping were performed in patients under artificial respiration. Parenchymal xenon and iodine distribution were mapped and correlated with structural or vascular abnormalities. In all datasets, image quality was sufficient for a comprehensive image reading of the pulmonary CTA images, lung window images and pulmonary functional parameter maps and led to expedient results in each patient. With dual-source CT systems, DECT of the lung with iodine or xenon administration is technically feasible and makes it possible to depict the regional iodine or xenon distribution representing the local perfusion and ventilation. (orig.)

  18. Pulmonary ventilation and perfusion imaging with dual-energy CT

    International Nuclear Information System (INIS)

    To evaluate the feasibility of dual-energy CT (DECT) ventilation imaging in combination with DE perfusion mapping for a comprehensive assessment of ventilation, perfusion, morphology and structure of the pulmonary parenchyma. Two dual-energy CT acquisitions for xenon-enhanced ventilation and iodine-enhanced perfusion mapping were performed in patients under artificial respiration. Parenchymal xenon and iodine distribution were mapped and correlated with structural or vascular abnormalities. In all datasets, image quality was sufficient for a comprehensive image reading of the pulmonary CTA images, lung window images and pulmonary functional parameter maps and led to expedient results in each patient. With dual-source CT systems, DECT of the lung with iodine or xenon administration is technically feasible and makes it possible to depict the regional iodine or xenon distribution representing the local perfusion and ventilation. (orig.)

  19. Incorporating virtual reality graphics with brain imaging for assessment of sport-related concussions.

    Science.gov (United States)

    Slobounov, Semyon; Sebastianelli, Wayne; Newell, Karl M

    2011-01-01

    There is a growing concern that traditional neuropsychological (NP) testing tools are not sensitive to detecting residual brain dysfunctions in subjects suffering from mild traumatic brain injuries (MTBI). Moreover, most MTBI patients are asymptomatic based on anatomical brain imaging (CT, MRI), neurological examinations and patients' subjective reports within 10 days post-injury. Our ongoing research has documented that residual balance and visual-kinesthetic dysfunctions along with its underlying alterations of neural substrates may be detected in "asymptomatic subjects" by means of Virtual Reality (VR) graphics incorporated with brain imaging (EEG) techniques. PMID:22254575

  20. Evaluation of CT dose and image quality in Recife, Brazil

    International Nuclear Information System (INIS)

    The objective of this work was to perform a dosimetry study of six CT scanners located in Recife, Brazil, and to evaluate the image quality of these equipments. In this work, the volume CT air kerma index (CVOL) and the air kerma length product (PKL,CT) were estimated. These quantities were calculated using normalized weighted air kerma ind ices in CT standard dosimetry phantoms (nCW), supplied by the ImPACT group for several CT scanners, and the scanning parameters of 15 adult examinations of the head, chest, abdomen and abdomen and pelvis of each institution. The image quality tests were performed using the phantom and accreditation protocol from the American College of Radiology (ACR). The results showed a wide variation of air kerma values for the six evaluated institutions. The CVOL values for head scans varied between 11 and 59 mGy and the PKL,CT, from 49 to 545 mGy.cm The chest examinations presented CVOL values varying from 6 to 15 mGy, and PKL,CT values between 120 and 466 mGy.cm. For abdominal scans, the estimated CVOL values varied between 5 and 14 mGy, and the PKL,CT values varied from 96 to 425 mGy.cm. The wide variation of air kerma between different centres is related to the type of scanner and also to the scanning protocol. The results also showed that, although the CVOL and PKL,CT values are compatible to the European reference levels, the image quality did not attend all ACR CT accreditation requirements. (author)

  1. Phantom validation of coregistration of PET and CT for image-guided radiotherapy

    International Nuclear Information System (INIS)

    Radiotherapy treatment planning integrating positron emission tomography (PET) and computerized tomography (CT) is rapidly gaining acceptance in the clinical setting. Although hybrid systems are available, often the planning CT is acquired on a dedicated system separate from the PET scanner. A limiting factor to using PET data becomes the accuracy of the CT/PET registration. In this work, we use phantom and patient validation to demonstrate a general method for assessing the accuracy of CT/PET image registration and apply it to two multi-modality image registration programs. An IAEA (International Atomic Energy Association) brain phantom and an anthropomorphic head phantom were used. Internal volumes and externally mounted fiducial markers were filled with CT contrast and 18F-fluorodeoxyglucose (FDG). CT, PET emission, and PET transmission images were acquired and registered using two different image registration algorithms. CT/PET Fusion (GE Medical Systems, Milwaukee, WI) is commercially available and uses a semi-automated initial step followed by manual adjustment. Automatic Mutual Information-based Registration (AMIR), developed at our institution, is fully automated and exhibits no variation between repeated registrations. Registration was performed using distinct phantom structures; assessment of accuracy was determined from registration of the calculated centroids of a set of fiducial markers. By comparing structure-based registration with fiducial-based registration, target registration error (TRE) was computed at each point in a three-dimensional (3D) grid that spans the image volume. Identical methods were also applied to patient data to assess CT/PET registration accuracy. Accuracy was calculated as the mean with standard deviation of the TRE for every point in the 3D grid. Overall TRE values for the IAEA brain phantom are: CT/PET Fusion=1.71±0.62 mm, AMIR=1.13±0.53 mm; overall TRE values for the anthropomorphic head phantom are: CT/PET Fusion=1.66±0

  2. Evaluation of accuracy in target positions of multmodality imaging using brain phantom

    International Nuclear Information System (INIS)

    Determination of target positions in radiation therapy or radiosurgery is critical to the successful treatment. It is often difficult to recognize the target position only from single image modality since each image modality has unique image pattern and image distortion problem. The purpose of this study is to evaluate the accuracy of target positions with multimodality brain phantom. We obtained CT, MR, and SPECT scan images with the specially designed brain phantom. Brain phantom consists of brain for images and frame for localization. The phantom was a water fillable cylinder containing 58 axial layers of 2.0 mm thickness. Each layer allows water to permeate various regions to match gray matter to white matter of 1:1 ratio. Localization frame with 5mm inner diameter and 150/160 mm length were attached to the outside of the brain slice and inside of the phantom cylinder. The phantom was filled with 0.16 M CuSO4 solution for MRI scan, and distilled water for CT and 15mCi (555 MBq) Tc-99m for SPECT. Axial slice images and volume images including the targets and localizer were obtained for each modality. To evaluate the errors in target positions, the position of localization and target balls measured in SPECT were compared with MR and CT. Transformation parameters for translation, rotation and scaling were determined by surface matching each SPECT with MR and CT images. Multimodality phantom was very useful to evaluate the accuracy of target positions among the different types of image modality such as CT, MR and SPECT

  3. Flash imaging in dual source CT (DSCT)

    Science.gov (United States)

    Bruder, H.; Petersilka, M.; Mehldau, H.; Heidinger, W.; Allmendinger, T.; Schmidt, B.,; Raupach, R.; Thierfelder, C.,; Stierstorfer, K.; Flohr, T.

    2009-02-01

    We present new acquisition modes of a recently introduced dual-source computed tomography (DSCT) system equipped with two X-ray tubes and two corresponding detectors, mounted onto the rotating gantry with an angular offset of typically 90°. Due to the simultaneous acquisition of complementary data, the minimum exposure time is reduced by a factor of two compared to a single-source CT system (SSCT). The correspondingly improved temporal resolution is beneficial for cardiac CT. Also, maximum table feed per rotation in a spiral mode can be increased by a factor of 2 compared to SSCT, which provides benefits both for cardiac CT and non-cardiac CT. In an ECG-triggered mode the entire cardiac volume can be scanned within a fraction of one cardiac RR-cycle. At a rotation time of 0.28s using a detector with 64×0.6 mm beam collimation, the scan time of the entire heart is less than 0.3s at a temporal resolution of 75 ms. It will be shown, that the extremely fast cardiac scan reduces the patient dose to a theoretical lowest limit: for a 120 kV scan the dose level for a typical cardiac CT scan is well below 2 mSv. Using further protocol optimization (scan range adaptation, 100kV), the radiation dose can be reduced below 1mSv.

  4. Imaging Brain Development: Benefiting from Individual Variability

    OpenAIRE

    Megha Sharda; Nicholas E.V. Foster; Hyde, Krista L.

    2015-01-01

    Human brain development is a complex process that evolves from early childhood to young adulthood. Major advances in brain imaging are increasingly being used to characterize the developing brain. These advances have further helped to elucidate the dynamic maturational processes that lead to the emergence of complex cognitive abilities in both typical and atypical development. However, conventional approaches involve categorical group comparison models and tend to disregard the role of widesp...

  5. NEMA and clinical evaluation of a novel brain PET-CT scanner

    Science.gov (United States)

    Grogg, Kira S.; Toole, Terrence; Ouyang, Jinsong; Zhu, Xuping; Normandin, Marc; Johnson, Keith; Alpert, Nathaniel M.; Fakhri, Georges El

    2016-01-01

    The aim of this study was to determine the performance of a novel mobile human brain/small animal PET-CT system, developed by Photo Diagnostic Systems Inc. The scanner has a 35.7-cm diameter bore and a 22-cm axial extent. The detector ring has 7 modules each with 3×4 cerium-doped lutetium yttrium orthosilicate crystal blocks, each consisting of 22×22 outer layer and 21×21 inner layer crystals, each layer 1 cm thick. Light is collected by 12×12 SiPMs. The integrated CT can be used for attenuation correction and anatomical localization. The scanner was designed as a low-cost device that nevertheless produces high-quality PET images with the unique capability of battery-powered propulsion, enabling use in many settings. Methods Spatial resolution, sensitivity and noise-equivalent count rate (NECR) were measured based on the National Electrical Manufacturers Association NU2-2012 procedures. Reconstruction was done with tight energy and timing cuts: 400-650 keV and 7ns, and loose cuts: 350-700 keV and 10ns. Additional image quality measurements were made from phantoms, human, and animal studies. Performance was compared to a reference scanner (ECAT Exact HR+) with comparable imaging properties. Results The full-width half-max transverse resolution at 1 cm (10 cm) radius is 3.2 mm (5.2 mm radial, 3.1 mm tangential) and the axial resolution is 3.5 mm (4.0 mm). For tight (loose) cuts, a sensitivity of 7.5 (11.7) kcps/MBq at the center increases to 8.8 (13.9) kcps/MBq at a 10 cm radial offset. The maximum NECR of 19.5 (22.7) kcps was achieved for an activity concentration of 2.9 kBq/ml. Contrast recovery for 4:1 hot cylinder to warm background was 76% for the 25 mm diameter cylinder, but decreased with decreasing cylinder size. The quantitation agrees within 2% of the known activity distribution and concentration. Brain phantom and human scans have shown agreement in SUV values and image quality with the HR+. Conclusion We have characterized the performance of the NeuroPET/CT

  6. 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...

  7. MR and CT image fusion of the cervical spine: a noninvasive alternative to CT-myelography

    Science.gov (United States)

    Hu, Yangqiu; Mirza, Sohail K.; Jarvik, Jeffrey G.; Heagerty, Patrick J.; Haynor, David R.

    2005-04-01

    CT-Myelography (CTM) is routinely used for planning surgery for degenerative disease of the spine, but its invasive nature, significant potential morbidity, and high costs make a noninvasive substitute desirable. We report our work on evaluating CT and MR image fusion as an alternative to CTM. Because the spine is only piecewise rigid, a multi-rigid approach to the registration of spinal CT and MR images was developed (SPIE 2004), in which the spine on CT images is first segmented into separate vertebrae, each of which is then rigidly registered with the corresponding vertebra on MR images. The results are then blended to obtain fusion images. Since they contain information from both modalities, we hypothesized that fusion images would be equivalent to CTM. To test this we selected 34 patients who had undergone MRI and CTM for degenerative disease of the cervical spine, and used the multi-rigid approach to produce fused images. A clinical vignette for each patient was created and presented along with either CT/MR fusion images or CTM images. A group of spine surgeons are asked to formulate detailed surgical plans based on each set of images, and the surgical plans are compared. A similar study assessing diagnostic agreement is being performed with neuroradiologists, who also assess the accuracy of registration. Our work to date has demonstrated the feasibility of segmentation and multi-rigid fusion in clinical cases and the acceptability of the questionnaire to physicians. Preliminary analysis of one surgeon's and one neuroradiologist"s evaluation has been performed.

  8. SU-E-I-58: Detecting Tumors with Extremely Low Contrast in CT Images

    Energy Technology Data Exchange (ETDEWEB)

    Sheng, K; Gou, S; Kupelian, P; Steiberg, M; Low, D [UCLA School of Medicine, Los Angeles, CA (United States)

    2014-06-01

    Purpose: Tumors such as the prostate focal lesions and the brain metastases have extremely low CT contrast and MRI is usually used for target delineation. The target contours are propagated to the CT for treatment planning and patient positioning. We have employed an advanced denoising method eliminating the noise and allow magnification of subtle contrast of these focal lesions on CT. Methods: Five prostate and two brain metastasis patients with MRI T2, diffusion or dynamic contrast enhanced (DCE) images confirmed focal lesions were included. One brain patients had 5 metastases. A block matching 3D (BM3D) algorithm was adapted to reduce the noise of kVCT images used for treatment planning. The gray-level range of the resultant images was narrowed to magnify the tumor-normal tissue contrast. Results: For the prostate patients, denoised kVCT images showed focal regions at 5, 8,11-1, 2, and 8–10 oclock for the 5 patients, this is highly consistent to the radiologist confirmed focal lesions based on MRI at 5, 7, 11-1, 2 and 8–10 oclock in the axial plane. These CT focal regions matched well with the MRI focal lesions in the cranio-caudal position. The average increase in density compared to background prostate glands was 0.86%, which corresponds to ∼50% increase in cellularity and is lower than the average CT noise level of 2.4%. For the brain patients, denoised kVCT showed 5/6 metastases. The high CT-density region of a metastasis is 2-mm off from its corresponding elevated MRI perfusion center. Overall the detecting sensitivity was 91%. Conclusion: It has been preliminarily demonstrated that the higher tumor cellularity can be detected using kVCT. The low contrast-to-noise information requires advanced denoising to reveal. The finding is significant to radiotherapy by providing an additional tool to locate focal lesions for confirming MRI-CT registration and providing a highly accessible outcome assessment tool.

  9. Technical aspects of CT imaging of the spine

    OpenAIRE

    Tins, Bernhard

    2010-01-01

    This review article discusses technical aspects of computed tomography (CT) imaging of the spine. Patient positioning, and its influence on image quality and movement artefact, is discussed. Particular emphasis is placed on the choice of scan parameters and their relation to image quality and radiation burden to the patient. Strategies to reduce radiation burden and artefact from metal implants are outlined. Data acquisition, processing, image display and steps to reduce artefact are reviewed...

  10. 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)

  11. 99mTc-HMPAO Brain SPECT in Seizure Disorder: Comparison Brain SPECT, MRI / CT and EEG

    International Nuclear Information System (INIS)

    We studied 115 patients with seizure who had been performed brain SPECT brain MRI of CT and EEG. To evaluate the pattern of brain SPECT in seizure patients 28 of them had secondary epilepsies, 87 had primary epilepsies. In primary epilepsies, 42 were generalized seizure and 45 were partial seizure. The causes of secondary epilepsies were congenital malformation, cerebromalacia, cerebral infarction ultiple sclerosis, AV-malformation. granuloma and etc, in order. In 28 secondary epilepsies, 25 of them, brain SPECT lesions was concordant with MRI or CT lesions. 3 were disconcordant. The brain SPECT findings of generalized seizure were normal in 22 patients, diffuse irregular decreased perfusion in 8, decreased in frontal cortex in 4. temporal in 5 and frontotemporal in 3. In 45 partial seizure, 19 brain SPECT were concordant with EEG (42.4%).

  12. Molecular imaging agents for SPECT (and SPECT/CT)

    Energy Technology Data Exchange (ETDEWEB)

    Gnanasegaran, Gopinath [Guy' s and St Thomas' NHS Foundation Trust, Department of Nuclear Medicine, London (United Kingdom); Ballinger, James R. [Guy' s and St Thomas' NHS Foundation Trust, Department of Nuclear Medicine, London (United Kingdom); King' s College London, Division of Imaging Sciences and Biomedical Engineering, London (United Kingdom)

    2014-05-15

    The development of hybrid single photon emission computed tomography/computed tomography (SPECT/CT) cameras has increased the diagnostic value of many existing single photon radiopharmaceuticals. Precise anatomical localization of lesions greatly increases diagnostic confidence in bone imaging of the extremities, infection imaging, sentinel lymph node localization, and imaging in other areas. Accurate anatomical localization is particularly important prior to surgery, especially involving the parathyroid glands and sentinel lymph node procedures. SPECT/CT plays a role in characterization of lesions, particularly in bone scintigraphy and radioiodine imaging of metastatic thyroid cancer. In the development of novel tracers, SPECT/CT is particularly important in monitoring response to therapies that do not result in an early change in lesion size. Preclinical SPECT/CT devices, which actually have spatial resolution superior to PET/CT devices, have become essential in characterization of the biodistribution and tissue kinetics of novel tracers, allowing coregistration of serial studies within the same animals, which serves both to reduce biological variability and reduce the number of animals required. In conclusion, SPECT/CT increases the utility of existing radiopharmaceuticals and plays a pivotal role in the evaluation of novel tracers. (orig.)

  13. CT and MR imaging after middle ear surgery.

    Science.gov (United States)

    Kösling, S; Bootz, F

    2001-11-01

    This article describes the current value of imaging in patients after stapes surgery and surgery after chronic otitis media including cholesteatoma. Possibilities and limits of computed tomography (CT) and MRI are described and most important investigation parameters are mentioned. After otosclerosis surgery, CT is the method of first choice in detection of reasons for vertigo and/or recurrent hearing loss in the later postoperative phase. CT may show the position and condition of prosthesis, scarring around the prosthesis and otospongiotic foci. Sometimes, it gives indirect hints for perilymphatic fistulas and incus necrosis. MRI is able to document inner ear complications. CT has a high negative predictive value in cases with a free cavity after mastoidectomy. Localized opacities or total occlusion are difficult to distinguish by CT alone. MRI provides important additional information in the differentiation of cholesterol granuloma, cholesteatoma, effusion, granulation and scar tissue. PMID:11704358

  14. CT and MR imaging after middle ear surgery

    International Nuclear Information System (INIS)

    This article describes the current value of imaging in patients after stapes surgery and surgery after chronic otitis media including cholesteatoma. Possibilities and limits of computed tomography (CT) and MRI are described and most important investigation parameters are mentioned. After otosclerosis surgery, CT is the method of first choice in detection of reasons for vertigo and/or recurrent hearing loss in the later postoperative phase. CT may show the position and condition of prosthesis, scarring around the prosthesis and otospongiotic foci. Sometimes, it gives indirect hints for perilymphatic fistulas and incus necrosis. MRI is able to document inner ear complications. CT has a high negative predictive value in cases with a free cavity after mastoidectomy. Localized opacities or total occlusion are difficult to distinguish by CT alone. MRI provides important additional information in the differentiation of cholesterol granuloma, cholesteatoma, effusion, granulation and scar tissue

  15. CT and MR imaging after middle ear surgery

    Energy Technology Data Exchange (ETDEWEB)

    Koesling, Sabrina E-mail: sabrina.koesling@medizin.uni-halle.de; Bootz, F

    2001-11-01

    This article describes the current value of imaging in patients after stapes surgery and surgery after chronic otitis media including cholesteatoma. Possibilities and limits of computed tomography (CT) and MRI are described and most important investigation parameters are mentioned. After otosclerosis surgery, CT is the method of first choice in detection of reasons for vertigo and/or recurrent hearing loss in the later postoperative phase. CT may show the position and condition of prosthesis, scarring around the prosthesis and otospongiotic foci. Sometimes, it gives indirect hints for perilymphatic fistulas and incus necrosis. MRI is able to document inner ear complications. CT has a high negative predictive value in cases with a free cavity after mastoidectomy. Localized opacities or total occlusion are difficult to distinguish by CT alone. MRI provides important additional information in the differentiation of cholesterol granuloma, cholesteatoma, effusion, granulation and scar tissue.

  16. Research on THz CT system and image reconstruction algorithm

    Science.gov (United States)

    Li, Ming-liang; Wang, Cong; Cheng, Hong

    2009-07-01

    Terahertz Computed Tomography takes the advantages of not only high resolution in space and density without image overlap but also the capability of being directly used in digital processing and spectral analysis, which determine it to be a good choice in parameter detection for process control. But Diffraction and scattering of THz wave will obfuscate or distort the reconstructed image. In order to find the most effective reconstruction method to build THz CT model. Because of the expensive cost, a fan-shaped THz CT industrial detection system scanning model, which consists of 8 emitters and 32 receivers, is established based on studying infrared CT technology. The model contains control and interface, data collecting and image reconstruction sub-system. It analyzes all the sub-function modules then reconstructs images with algebraic reconstruction algorithm. The experimental result proves it to be an effective, efficient algorithm with high resolution and even better than back-projection method.

  17. 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.

  18. Optimization of K-edge imaging with spectral CT

    OpenAIRE

    He, Peng; Wei, Biao; Cong, Wenxiang; Wang, Ge

    2012-01-01

    Purpose: Spectral/multienergy CT has the potential to distinguish different materials by K-edge characteristics. K-edge imaging involves the two energy bins on both sides of a K-edge. The authors propose a K-edge imaging optimization model to determine these two energy bins.

  19. CT guided diffuse optical tomography for breast cancer imaging

    Science.gov (United States)

    Baikejiang, Reheman; Zhang, Wei; Zhu, Dianwen; Li, Changqing

    2016-03-01

    Diffuse optical tomography (DOT) has attracted attentions in the last two decades due to its intrinsic sensitivity in imaging chromophores of tissues such as blood, water, and lipid. However, DOT has not been clinically accepted yet due to its low spatial resolution caused by strong optical scattering in tissues. Structural guidance provided by an anatomical imaging modality enhances the DOT imaging substantially. Here, we propose a computed tomography (CT) guided multispectral DOT imaging system for breast cancer detection. To validate its feasibility, we have built a prototype DOT imaging system which consists of a laser at wavelengths of 650 and an electron multiplying charge coupled device (EMCCD) camera. We have validated the CT guided DOT reconstruction algorithms with numerical simulations and phantom experiments, in which different imaging setup parameters, such as projection number of measurements, the width of measurement patch, have been investigated. Our results indicate that an EMCCD camera with air cooling is good enough for the transmission mode DOT imaging. We have also found that measurements at six projections are sufficient for DOT to reconstruct the optical targets with 4 times absorption contrast when the CT guidance is applied. Finally, we report our effort and progress on the integration of the multispectral DOT imaging system into a breast CT scanner.

  20. Male patients dosimetry undergoing brain PET/CT exam for diagnosis of mild cognitive impairment; Dosimetria de pacientes masculinos submetidos ao exame de PET/CT cerebral para diagnostico de comprometimento cognitivo leve

    Energy Technology Data Exchange (ETDEWEB)

    Santana, P.C.; Mamede, M.; Carvalho, F.M.V., E-mail: pridili@gmail.com [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil). Fac. de Medicina. Departamento de Anatomia e Imagem; Mourao, A.P. [Centro Federal de Educacao Tecnologica de Minas Gerais (CEFET-MG), Belo Horizonte, MG (Brazil). Departamento de Engenharia Eletrica; Silva, T.A.; Oliveira, P.M.C. [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil)

    2013-08-15

    Diagnosis of Mild Cognitive Impairment (MCI) can indicate an initial dementia framework, or increase in the likelihood of developing this. The PET/CT (positron emission tomography associated with computed tomography) has shown excellent prospects for MCI diagnosis. The PET/CT helps diagnosis, but the patients effective dose is higher, it depends on the computed tomography (CT) protocol and the radiopharmaceutical patient injected activity. This study evaluates the dose in 38 male patients undergoing this technique for MCI diagnosis. To assess the radiation level from CT modality imaging was used TLD100 detectors embedded in a male anthropomorphic Alderson Randon® phantom, undergoing the same imaging protocol to which patients were referred. The dose resulting of radiopharmaceutical injected activity was estimated using the ICRP106 model proposed. The PET / CT effective dose for producing image was (5.12 ± 0.90) mSv. The contribution to the effective dose due to the FDG brain incorporation was (0.12 ± 0.01) mSv and thyroid (0.13 ± 0.02) mSv. The effective dose contribution due to brain and thyroid CT irradiation was (0.18 ± 0.01) mSv and (0.010 ± 0.001) mSv, respectively. The use of optimized CT protocols and FDG injected activity reduction can assist in this procedure dose reduction. (author)

  1. CT and MR imaging in the evaluation of leptomeningeal metastases

    International Nuclear Information System (INIS)

    Objective: To study the manifestations of leptomeningeal metastases on CT and MR imaging, and evaluate the diagnostic significance of both modalities for this disease. Methods: Clinical and neuroradiological data of 21 cases with leptomeningeal metastases were retrospectively reviewed. In this series, 16 patients were studied by CT and 7 patients by MRI, 2 patients by both CT and MRI. Results: Abnormal enhancement of pia and subarachnoid space, appearing as diffuse pattern in 10 cases, nodular pattern in 8 cases and mixed pattern with diffuse plus nodules in 3 cases, were visualized by CE-CT and Gd-MRI. Diffuse enhancement followed the convolutions of gyri and surface of brainstem, and extended into cerebral cisterns and sulci. the foci appeared as enhanced nodules 0.2-3.0 cm in diameter and 1 or more in number. Nodules with infiltration of cerebral parenchymal were found in 4 patients. In 86% of all cases, diffuse or nodular foci occurred in basilar systems and adjacent cerebellar and cerebral sulci. There were 4 cases associated with ependymal nodular enhancement and 10 cases with widened irregular tentorial enhancement. Intracerebral metastases in 9 cases and hydrocephalus in 13 cases were found in this series. Conclusions: CE-CT and Gd-MRI are had significant clinical diagnostic value for leptomeningeal metastases, Gd-MRI is superior to CE-CT. Because of the limitation in the evaluation of leptomeningeal invasion by neoplasms on CT and MRI, definitive diagnosis of leptomeningeal metastases depends on combination of clinical and imaging data

  2. 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...

  3. CT and MR imaging of gynecological emergency disease

    International Nuclear Information System (INIS)

    We describe the CT and MRI findings of gynecologic emergency diseases: pelvic inflammatory disease, ectopic pregnancy, ovarian hemorrhage, ovarian torsion, rupture of ovarian tumor, eclampsia, and HELLP (hemolysis, elevated liver enzymes, and low platelet count) syndrome. Diagnostic keys to these diseases are presented in this review. CT and MRI play a complementary role to sonography in accurately diagnosing these diseases. In situations that require an exact, immediate diagnosis, radiologists should be familiar with the key imaging findings. (author)

  4. Super pipe lining system for 3-D CT imaging

    International Nuclear Information System (INIS)

    A new idea for 3-D CT image reconstruction system is introduced. For the network has very important improvement in recently years, it realizes that network computing replace the traditional serial system processing. CT system's works are carried in a multi-level fashion, it will make the tedious works processed by many computers linked by local network in the same time. So greatly improve the reconstruction speed

  5. Pediatric renal leukemia: spectrum of CT imaging findings

    International Nuclear Information System (INIS)

    The kidneys are a site of extramedullary leukemic disease that can be readily detected by CT. To demonstrate the spectrum of CT findings in children with renal leukemic involvement. Twelve children were identified retrospectively as having renal leukemic involvement by contrast-enhanced CT of the abdomen. Contrast-enhanced CT images through the kidneys of each patient were reviewed by two pediatric radiologists. Pertinent imaging findings and renal lengths were documented. The electronic medical record was accessed to obtain relevant clinical and pathologic information. Five patients with renal leukemic involvement presented with multiple bilateral low-attenuation masses, while three patients demonstrated large areas of wedge-shaped and geographic low attenuation. Four other patients presented with unique imaging findings, including a solitary unilateral low-attenuation mass, solitary bilateral low-attenuation masses, multiple bilateral low-attenuation masses including unilateral large conglomerate masses, and bilateral areas of ill-defined parenchymal low attenuation. Two patients showed unilateral nephromegaly, while eight other patients showed bilateral nephromegaly. Two patients had normal size kidneys. Two patients had elevated serum creatinine concentrations at the time of imaging. Renal leukemic involvement in children can present with a variety of CT imaging findings. Focal renal abnormalities as well as nephromegaly are frequently observed. Most commonly, renal leukemic involvement does not appear to impair renal function. (orig.)

  6. MR imaging of associated brain injuries in cases of acute extradural hematoma

    International Nuclear Information System (INIS)

    To assess the efficacy of magnetic resonance (MR) imaging for detection of associated brain injuries in cases of extradural hematoma (EDH), 32 patients with EDH were examined by MR. CT detected associated lesion in eleven patients (34%), while MR detected them in 24 patients (75%). MR is more sensitive than CT in detecting associated lesions, especially when T2-weighted imaging is used. Non-hemorrhagic contusions adjacent to EDH and near the cranial base were well shown by MR; however, they tended to be missed by CT. EEG findings were clearly related to abnormalities detected by MR. Coupling between functional change and organic change was confirmed. The improved detection and anatomic localization of associated brain injuries by MR should allow more accurate assessment of brain injuries, and sophisticated management of EDH patient. The authors also discuss the cardiorespiratory monitoring and support during MRI examination in critically ill patients. (author)

  7. Efficient iterative image reconstruction algorithm for dedicated breast CT

    Science.gov (United States)

    Antropova, Natalia; Sanchez, Adrian; Reiser, Ingrid S.; Sidky, Emil Y.; Boone, John; Pan, Xiaochuan

    2016-03-01

    Dedicated breast computed tomography (bCT) is currently being studied as a potential screening method for breast cancer. The X-ray exposure is set low to achieve an average glandular dose comparable to that of mammography, yielding projection data that contains high levels of noise. Iterative image reconstruction (IIR) algorithms may be well-suited for the system since they potentially reduce the effects of noise in the reconstructed images. However, IIR outcomes can be difficult to control since the algorithm parameters do not directly correspond to the image properties. Also, IIR algorithms are computationally demanding and have optimal parameter settings that depend on the size and shape of the breast and positioning of the patient. In this work, we design an efficient IIR algorithm with meaningful parameter specifications and that can be used on a large, diverse sample of bCT cases. The flexibility and efficiency of this method comes from having the final image produced by a linear combination of two separately reconstructed images - one containing gray level information and the other with enhanced high frequency components. Both of the images result from few iterations of separate IIR algorithms. The proposed algorithm depends on two parameters both of which have a well-defined impact on image quality. The algorithm is applied to numerous bCT cases from a dedicated bCT prototype system developed at University of California, Davis.

  8. Brain and nervous system (image)

    Science.gov (United States)

    The nervous system controls the many complicated and interconnected functions of the body and mind. Motor, sensory cognitive and autonomic function are all coordinated and driven by the brain and nerves. As people age, nerve ...

  9. Brain and nervous system (image)

    Science.gov (United States)

    ... complicated and interconnected functions of the body and mind. Motor, sensory cognitive and autonomic function are all coordinated and driven by the brain and nerves. As people age, nerve cells deteriorated ...

  10. Multiscale registration of planning CT and daily cone beam CT images for adaptive radiation therapy

    International Nuclear Information System (INIS)

    Adaptive radiation therapy (ART) is the incorporation of daily images in the radiotherapy treatment process so that the treatment plan can be evaluated and modified to maximize the amount of radiation dose to the tumor while minimizing the amount of radiation delivered to healthy tissue. Registration of planning images with daily images is thus an important component of ART. In this article, the authors report their research on multiscale registration of planning computed tomography (CT) images with daily cone beam CT (CBCT) images. The multiscale algorithm is based on the hierarchical multiscale image decomposition of E. Tadmor, S. Nezzar, and L. Vese [Multiscale Model. Simul. 2(4), pp. 554-579 (2004)]. Registration is achieved by decomposing the images to be registered into a series of scales using the (BV, L2) decomposition and initially registering the coarsest scales of the image using a landmark-based registration algorithm. The resulting transformation is then used as a starting point to deformably register the next coarse scales with one another. This procedure is iterated at each stage using the transformation computed by the previous scale registration as the starting point for the current registration. The authors present the results of studies of rectum, head-neck, and prostate CT-CBCT registration, and validate their registration method quantitatively using synthetic results in which the exact transformations our known, and qualitatively using clinical deformations in which the exact results are not known.

  11. Brain water mapping with MR imaging

    International Nuclear Information System (INIS)

    This paper reports on a recently developed MR imaging technique to determine the spatial distribution of brain water to healthy volunteers. A noninvasive MR imaging technique to obtain absolute measurements of brain water has been developed and validated with phantom and animal studies. Patient confirmation was obtained from independent gravimetric measurements of brain tissue samples harvested by biopsy. This approach entails the production of accurate T1 maps from multiple inversion recovery images of a selected anatomic section and their subsequent conversion into an absolute water image by means of a previously determined calibration curve. Twenty healthy volunteers were studied and their water distribution was determined in a standard section. The following brain water values means and SD grams of water per gram of tissue) were obtained for selected brain regions; white matter, 68.9% ± 1.0; corpus callosum, 67.4% ± 1.1; thalamus, 75.3% ± 1.4; and caudate nucleus, 80.3% ± 1.4. MR imaging water mapping is a valid means of determining water content in a variety of brain tissues

  12. MRI Brain Image Segmentation based on Thresholding

    Directory of Open Access Journals (Sweden)

    G. Evelin Sujji, Y.V.S. Lakshmi, G. Wiselin Jiji

    2013-03-01

    Full Text Available Medical Image processing is one of the mostchallenging topics in research field. The mainobjective of image segmentation is to extract variousfeatures of the image that are used foranalysing,interpretation and understanding of images.Medical Resonance Image plays a major role inMedical diagnostics. Image processing in MRI ofbrain is highlyessential due to accurate detection ofthe type of brain abnormality which can reduce thechance of fatal result. This paper outlines anefficient image segmentation technique that candistinguish the pathological tissues such asedemaandtumourfrom thenormal tissues such as WhiteMatter(WM,GreyMatter(GM, andCerebrospinal Fluid(CSF. Thresholding is simplerand most commonly used techniques in imagesegmentation. This technique can be used to detectthe contour of thetumourin brain.

  13. NIH Conference. Brain imaging: aging and dementia

    International Nuclear Information System (INIS)

    The brain imaging techniques of positron emission tomography using [18F]-fluoro-2-deoxy-D-glucose, and computed tomography, together with neuropsychological tests, were used to examine overall brain function and anatomy in three study populations: healthy men at different ages, patients with presumptive Alzheimer's disease, and adults with Down's syndrome. Brain glucose use did not differ with age, whereas an age-related decrement in gray matter volume was found on computed tomographic assessment in healthy subjects. Memory deficits were found to precede significant reductions in brain glucose utilization in mild to moderate Alzheimer's dementia. Furthermore, differences between language and visuoconstructive impairments in patients with mild to moderate Alzheimer's disease were related to hemispheric asymmetry of brain metabolism. Brain glucose utilization was found to be significantly elevated in young adults with Down's syndrome, compared with controls. The importance of establishing strict criteria for selecting control subjects and patients is explained in relation to the findings

  14. Radionuclide brain imaging in acquired immunodeficiency syndrome (AIDS)

    International Nuclear Information System (INIS)

    Infection with the Human Immunodeficiency Virus type 1 (HIV-1) may produce a variety of central nervous system (CNS) symptoms and signs. CNS involvement in patients with the Acquired Immunodeficiency Syndrome (AIDS) includes AIDS dementia complex or HIV-1 associated cognitive/motor complex (widely known as HIV encephalopathy), progressive multifocal leucoencephalopathy (PML), opportunistic infections such as Toxoplasma gondii, TB, Cryptococcus and infiltration by non-Hodgkin's B cell lymphoma. High resolution structural imaging investigations, either X-ray Computed Tomography (CT scan) or Magnetic Resonance Imaging (MRI) have contributed to the understanding and definition of cerebral damage caused by HIV encephalopathy. Atrophy and mainly high signal scattered white matter abnormalities are commonly seen with MRI. PML produces focal white matter high signal abnormalities due to multiple foci of demyelination. However, using structural imaging techniques there are no reliable parameters to distinguish focal lesions due to opportunistic infection (Toxoplasma gondii abscess) from neoplasm (lymphoma infiltration). It is studied the use of radionuclide brain imaging techniques in the investigation of HIV infected patients. Brain perfusion Single Photon Emission Tomography (SPET), neuroreceptor and Positron Emission Tomography (PET) studies are reviewed. Greater emphasis is put on the potential of some radiopharmaceuticals, considered to be brain tumour markers, to distinguish intracerebral lymphoma infiltration from Toxoplasma infection. SPET with 201Tl using quantification (tumour to non-tumour radioactivity ratios) appears a very promising technique to identify intracerebral lymphoma

  15. Radionuclide brain imaging in acquired immunodeficiency syndrome (AIDS)

    Energy Technology Data Exchange (ETDEWEB)

    Costa, D.C.; Gacinovic, S.; Miller, R.F. [London University College Medical School, Middlesex Hospital, London (United Kingdom)

    1995-09-01

    Infection with the Human Immunodeficiency Virus type 1 (HIV-1) may produce a variety of central nervous system (CNS) symptoms and signs. CNS involvement in patients with the Acquired Immunodeficiency Syndrome (AIDS) includes AIDS dementia complex or HIV-1 associated cognitive/motor complex (widely known as HIV encephalopathy), progressive multifocal leucoencephalopathy (PML), opportunistic infections such as Toxoplasma gondii, TB, Cryptococcus and infiltration by non-Hodgkin`s B cell lymphoma. High resolution structural imaging investigations, either X-ray Computed Tomography (CT scan) or Magnetic Resonance Imaging (MRI) have contributed to the understanding and definition of cerebral damage caused by HIV encephalopathy. Atrophy and mainly high signal scattered white matter abnormalities are commonly seen with MRI. PML produces focal white matter high signal abnormalities due to multiple foci of demyelination. However, using structural imaging techniques there are no reliable parameters to distinguish focal lesions due to opportunistic infection (Toxoplasma gondii abscess) from neoplasm (lymphoma infiltration). It is studied the use of radionuclide brain imaging techniques in the investigation of HIV infected patients. Brain perfusion Single Photon Emission Tomography (SPET), neuroreceptor and Positron Emission Tomography (PET) studies are reviewed. Greater emphasis is put on the potential of some radiopharmaceuticals, considered to be brain tumour markers, to distinguish intracerebral lymphoma infiltration from Toxoplasma infection. SPET with {sup 201}Tl using quantification (tumour to non-tumour radioactivity ratios) appears a very promising technique to identify intracerebral lymphoma.

  16. Maximization of the mutual information index for CT-CT image fusion

    International Nuclear Information System (INIS)

    Full text: The accuracy with which two different image sets are co-registered is vital to the delineation of tumour volumes in radiotherapy. In order to obtain a confidence level in the ability of CMS FOCAL V4.1.1 (St. Lois, USA) to co-register CT study sets for radiotherapy treatment planning a phantom study was undertaken. The image registration algorithm used by CMS is the maximization of mutual information. A Siemens Sensation 4 CT Scanner (Forchheim, Germany) was used to scan the phantoms for the study. The CMS FOCALSim application was used to co-register the different data sets. The co registration of two CT data sets was examined using two separate phantoms. The maximization of mutual information index (MMIl) when different parameters were varied was examined. The CT slice thickness was varied from 1mm up to 5mm as used in clinical CT Simulation protocols. The CT image field of view (FOV) was varied from 20cm to 50cm. The angle rotation of the phantom was varied. The various geometries within the phantom were rotated by known angles for co-registration with the default position. The inserts of different relative electron densities were removed for co-registration with the default position. The influence of these changes on the MMII was examined as an indication of the 'goodness' of the image co registration. The accuracy of the CT-CT registration was determined. The MMII ranged from 1.36 to 0.92 for the combination of CT slice thickness investigated. For the angle offset of the phantom the MMII ranged from 0.63 to 0.90. For the range of field of views investigated for the phantom the MMlI ranged from 0.49 to 1.01. For angle offset of only a single geometric component the MMII remained fairly uniform ranging from 0.686 to 0.690. For the removal of the various relative electron density inserts the bone inserts were found to have the most significant impact on the MMI. These results are clinically significant for patients that are scanned with contrast or

  17. PET/CT (and CT) instrumentation, image reconstruction and data transfer for radiotherapy planning

    International Nuclear Information System (INIS)

    The positron emission tomography in combination with CT in hybrid, cross-modality imaging systems (PET/CT) gains more and more importance as a part of the treatment-planning procedure in radiotherapy. Positron emission tomography (PET), as a integral part of nuclear medicine imaging and non-invasive imaging technique, offers the visualization and quantification of pre-selected tracer metabolism. In combination with the structural information from CT, this molecular imaging technique has great potential to support and improve the outcome of the treatment-planning procedure prior to radiotherapy. By the choice of the PET-Tracer, a variety of different metabolic processes can be visualized. First and foremost, this is the glucose metabolism of a tissue as well as for instance hypoxia or cell proliferation. This paper comprises the system characteristics of hybrid PET/CT systems. Acquisition and processing protocols are described in general and modifications to cope with the special needs in radiooncology. This starts with the different position of the patient on a special table top, continues with the use of the same fixation material as used for positioning of the patient in radiooncology while simulation and irradiation and leads to special processing protocols that include the delineation of the volumes that are subject to treatment planning and irradiation (PTV, GTV, CTV, etc.). General CT acquisition and processing parameters as well as the use of contrast enhancement of the CT are described. The possible risks and pitfalls the investigator could face during the hybrid-imaging procedure are explained and listed. The interdisciplinary use of different imaging modalities implies a increase of the volume of data created. These data need to be stored and communicated fast, safe and correct. Therefore, the DICOM-Standard provides objects and classes for this purpose (DICOM RT). Furthermore, the standard DICOM objects and classes for nuclear medicine (NM, PT) and

  18. PET/CT (and CT) instrumentation, image reconstruction and data transfer for radiotherapy planning.

    Science.gov (United States)

    Sattler, Bernhard; Lee, John A; Lonsdale, Markus; Coche, Emmanuel

    2010-09-01

    The positron emission tomography in combination with CT in hybrid, cross-modality imaging systems (PET/CT) gains more and more importance as a part of the treatment-planning procedure in radiotherapy. Positron emission tomography (PET), as a integral part of nuclear medicine imaging and non-invasive imaging technique, offers the visualization and quantification of pre-selected tracer metabolism. In combination with the structural information from CT, this molecular imaging technique has great potential to support and improve the outcome of the treatment-planning procedure prior to radiotherapy. By the choice of the PET-Tracer, a variety of different metabolic processes can be visualized. First and foremost, this is the glucose metabolism of a tissue as well as for instance hypoxia or cell proliferation. This paper comprises the system characteristics of hybrid PET/CT systems. Acquisition and processing protocols are described in general and modifications to cope with the special needs in radiooncology. This starts with the different position of the patient on a special table top, continues with the use of the same fixation material as used for positioning of the patient in radiooncology while simulation and irradiation and leads to special processing protocols that include the delineation of the volumes that are subject to treatment planning and irradiation (PTV, GTV, CTV, etc.). General CT acquisition and processing parameters as well as the use of contrast enhancement of the CT are described. The possible risks and pitfalls the investigator could face during the hybrid-imaging procedure are explained and listed. The interdisciplinary use of different imaging modalities implies a increase of the volume of data created. These data need to be stored and communicated fast, safe and correct. Therefore, the DICOM-Standard provides objects and classes for this purpose (DICOM RT). Furthermore, the standard DICOM objects and classes for nuclear medicine (NM, PT) and

  19. Extrapulmonary small cell sarcinoma: involvement of the brain without evidence of extracranial malignancy by serial PET/CT scans

    Directory of Open Access Journals (Sweden)

    Havlioglu Necat

    2008-09-01

    Full Text Available Abstract Background Extrapulmonary small cell carcinoma (EPSCC involving the brain is a rare manifestation of an uncommon tumor type. Case presentation We report a 59 year-old Caucasian female diagnosed with an EPSCC involving the left parietal lobe without detectable extracranial primary tumor followed by serial positron emission tomography/computed tomography (PET/CT imaging. Histopathological examination at both initial presentation and recurrence revealed small cell carcinoma. Serial PET/CT scans of the entire body failed to reveal any extracranial [18F]2-fluoro-2-deoxy-D-glucose (FDG avid lesions at either diagnosis or follow-up. Conclusion Chemotherapy may show a transient response in the treatment of EPSCC. Further studies are needed to help identify optimal treatment strategies. Combination PET/CT technology may be a useful tool to monitor EPSCC and assess for an occult primary malignancy.

  20. Ablation of atrial fibrillation using CT image integration

    International Nuclear Information System (INIS)

    In our case report we describe a catheter ablation in a patient with symptomatic, drug-refractory atrial fibrillation using the new CT image integrating mapping technology. Using image integration an arrhythmogenic right inferior pulmonary vein was revealed which was not found during conventional 3-dimensional mapping. Thereby we want to demonstrate potential impacts on safety and effectiveness of ablation strategies using an image integration technology, especially in cases of difficult anatomic variations. (author)

  1. 3D CT Imaging Method for Measuring Temporal Bone Aeration

    International Nuclear Information System (INIS)

    Objective: 3D volume reconstruction of CT images can be used to measure temporal bene aeration. This study evaluates the technique with respect to reproducibility and acquisition parameters. Material and methods: Helical CT images acquired from patients with radiographically normal temporal bones using standard clinical protocols were retrospectively analyzed. 3D image reconstruction was performed to measure the volume of air within the temporal bone. The appropriate threshold values for air were determined from reconstruction of a phantom with a known air volume imaged using the same clinical protocols. The appropriate air threshold values were applied to the clinical material. Results: Air volume was measured according to an acquisition algorithm. The average volume in the temporal bone CT group was 5.56 ml, compared to 5.19 ml in the head CT group (p = 0.59). The correlation coefficient between examiners was > 0.92. There was a wide range of aeration volumes among individual ears (0.76-18.84 ml); however, paired temporal bones differed by an average of just 1.11 ml. Conclusions: The method of volume measurement from 3D reconstruction reported here is widely available, easy to perform and produces consistent results among examiners. Application of the technique to archival CT data is possible using corrections for air segmentation thresholds according to acquisition parameters

  2. Magnetic resonance (MR) imaging in delayed encephalopathy of acute carbon monoxide poisoning - comparison with CT -

    International Nuclear Information System (INIS)

    Eleven magnetic resonance (MR) and computed tomographic (CT) imaging were performed in nine patients with mild to moderate degree of delayed neuropsychiatric symptoms following acute carbon monoxide (CO) poisoning, to evaluate the capability of MR in demonstrating any additional finding to CT. The MR images were obtained using 0.15 Tesla resistive system with various combination of three pulse sequences, including partial saturation recovery, T2-weighted spin echo and inversion recovery. Bilateral white matter abnormalities suggesting demyelination were demonstrated in 4 patients with MR and in only 2 patients with CT. The contrast discrimination between normal and abnormal white matter proved to be better with T2-weighted spin echo and inversion recovery than with partial saturation recovery and CT. But necrosis of the globus pallidus (1 patient) and diffuse atrophy (3 patients) were equally demonstrated on both MR and CT. It is suggested that MR be used as a initial imaging method in the evaluation of the delayed encephalopathy following acute CO poisoning, especially for the detection of the possible white matter lesions. Acute carbon monoxide (CO) poisoning produces hypoxia by displacing oxygen from hemoglobin and preventing its release from hemoglobin in tissues, often resulting in fetal event. Victims who survive acute CO poisoning may have various delayed symptoms and signs. Occasionally, an apparent recovery is followed within two days to three weeks by a sudden neurological deterioration. The degree of neuropsychiatric symptoms depends upon the extent and severity of the pathologic changes in the brain. The pathologic effects of CO poisoning are present in almost all organs of patients. However, the most important changes occur in the brain, which consist of necrosis of the globus pallidus and reticular zone of the substantia nigra, and the degeneration of the cerebral white matter. The diagnostic superiority of magnetic resonance (MR) over CT has already

  3. CT and MR imaging of spongiform leukoencephalopathy after heroin vapor inhalation

    International Nuclear Information System (INIS)

    Objective: To summarize the CT and MRI features of spongiform leucoencephalopathy after heroin vapor inhalation. Methods: The clinical characteristic, CT and MRI of 5 cases and biopsy of 1 case with heroin vapor inhalation induced spongiform leukoencephalopathy were analyzed. Results: CT and MRI appearances of spongiform leucoencephalopathy after heroin vapor inhalation were as follow: (1) Brain CT and MRI showed extensive symmetrical white matter lesions within bilateral cerebral and cerebellar hemispheres, the brainstem, and posterior limbs of the internal capsule. The cerebellum was heavily impaired. The most outstanding characteristics of the lesion was ring-like or butterfly-like in shape with clear margin in cerebellar hemispheres. (2) The lesion was bilateral and symmetrical. The margin of the lesion was clear. (3) A computed tomographic scan showed hypointense lesions. T1-weighted magnetic resonance imaging (MRI) showed hypointense lesions and T2-weighted MRI showed hyperintense lesions. (4) No enhancement with Gd-DTPA was revealed. (5) Spongiform vacuoles degeneration of white matter was the main morphological change by biopsy. Conclusion: Spongiform leukoencephalopathy should be considered if a patient showed acute cerebellar signs who had a history of inhaling heroin pyrolysate. The imaging manifestation of this disease is typical and the diagnosis can be made by head CT or MRI

  4. Brain Magnetic Resonance Imaging in Tyrosinemia

    International Nuclear Information System (INIS)

    A 3.5-year-old girl with tyrosinemia is reported. A computed tomography scan of the abdomen revealed multiple hepatic nodules. Brain magnetic resonance imaging revealed bilateral high-signal changes confined to the globus pallidus on T2-weighted images. Globus pallidus lesions likely represented neuropathologic changes such as astocytosis, delayed myelination, and status spongiosus (myelin splitting and vacuolation)

  5. Brain Morphometry Using Anatomical Magnetic Resonance Imaging

    Science.gov (United States)

    Bansal, Ravi; Gerber, Andrew J.; Peterson, Bradley S.

    2008-01-01

    The efficacy of anatomical magnetic resonance imaging (MRI) in studying the morphological features of various regions of the brain is described, also providing the steps used in the processing and studying of the images. The ability to correlate these features with several clinical and psychological measures can help in using anatomical MRI to…

  6. New developments in the imaging of brains

    International Nuclear Information System (INIS)

    A review is given for the imaging techniques of brains. Separate paragraphs are devoted to echography, computerized tomography and magnetic resonance imaging. Special attention is payed to new developments such as magnetic resonance spectroscopy used for metabolic processes. (R.B.) 11 refs

  7. MR tomography after head and brain trauma: Comparison with CT, EEG and neurological examination

    International Nuclear Information System (INIS)

    56 patients with head and brain trauma and in coma were studied prospectively by means of MRT, CT, EEG and neurological examination. All patients had initial CT and EEG admission. MRT showed that in our patients morphological return to normal was the exception. Patients with head and brain injuries should be examined by MRT during the course of their illness. The use of special sequences, such as gradient-echo sequences for the diagnosis of haemorrhagic contusions, is indicated. CT should be retained for evaluating bone injury and cerebral damage during the acute stage. (orig.)

  8. Advantages in functional imaging of the brain

    Directory of Open Access Journals (Sweden)

    Walter Mier

    2015-05-01

    Full Text Available As neuronal pathologies cause only minor morphological alterations, molecular imaging techniques are a prerequisite for the study of diseases of the brain. The development of molecular probes that specifically bind biochemical markers and the advances of instrumentation have revolutionized the possibilities to gain insight into the human brain organization and beyond this visualize structure-function and brain-behavior relationships. The review describes the development and current applications of functional brain imaging techniques with a focus on applications in psychiatry. A historical overview of the development of functional imaging is followed by the portrayal of the principles and applications of positron emission tomography (PET and functional magnetic resonance imaging (fMRI, two key molecular imaging techniques that have revolutionized the ability to image molecular processes in the brain. In the juxtaposition of PET and fMRI in hybrid PET/MRI scanners enhances the significance of both modalities for research in neurology and psychiatry and might pave the way for a new area of personalized medicine.

  9. Object recognition in brain CT-scans: Knowledge-based fusion of data from multiple feature extractors

    International Nuclear Information System (INIS)

    This paper describes a knowledge-based image interpretation system for the segmentation and labeling of a series of 2-D brain X-ray CT-scans, parallel to the orbito-metal plane. The system combines the image primitive information produced by different low level vision techniques in order to improve the reliability of the segmentation and the image interpretation. It is implemented in a blackboard environment that is holding various types of prior information and which controls the interpretation process. The scoring model is applied for the fusion of information derived from three types of image primitives (points, edges, and regions). A model, containing both analogical and propositional knowledge on the brain objects, is used to direct the interpretation process. The linguistic variables, introduced to describe the propositional features of the brain model, are defined by fuzzy membership functions. Constraint functions are applied to evaluate the plausibility of the mapping between image primitives and brain model data objects. Procedural knowledge has been integrated into different knowledge sources. Experimental results illustrate the reliability and robustness of the system against small variations in slice orientation and interpatient variability in the images

  10. Preliminary investigation of brain 18F-FDG PET imaging in neonate

    International Nuclear Information System (INIS)

    Objective: To study brain 18F-fluorodeoxyglucose (FDG) PET imaging and to understand its metabolic function in neonate with pneumonia and premature infants. Methods: Nine neonate with pneumonia and seven premature infants were examined with routine 18F-FDG PET brain scan. Results: The brain 18F-FDG PET image of neonate was significantly different from that of adult and child. The structure of whole brain was not clearly demarcated. The active glucose metabolic areas were in thalamus, cerebellum, sensorimotor cortex and basal ganglia. The 18F-FDG uptake was most in thalamus, while least in cerebral cortex. The image quality showed no significant difference among 1, 2 and 3 min transmission scan for attenuation correction. Conclusions: 18F-FDG PET brain imaging may be one of effective methods to study cerebral function and metabolism in neonate. But the CT transmission time should reduce to be the shortest. (authors)

  11. The utilization of dual source CT in imaging of polytrauma

    International Nuclear Information System (INIS)

    Despite the growing role of imaging, trauma remains the leading cause of death in people below the age of 45 years in the western industrialized countries. Trauma has been touted as the largest epidemic in the 20th century. The advent of MDCT has been the greatest advance in trauma care in the last 25 years. However, there are still challenges in CT imaging of the polytrauma individual including time restraints, diagnostic errors, radiation dose effects and bridging the gap between anatomy and physiology. This article will analyze these challenges and provide possible solutions offered by the unique design of the dual source CT scanner

  12. CT imaging of complications of catheter ablation for atrial fibrillation

    International Nuclear Information System (INIS)

    The complication rate following radiofrequency catheter ablation for atrial fibrillation is low (<5%). Complications include pericardial effusion, cardiac tamponade, pulmonary vein stenosis, oesophageal ulceration or perforation, atrio-oesophageal fistula formation, stroke/transient ischaemic attack, phrenic nerve injury, haematoma at the puncture site, and femoral arteriovenous fistula. Among available imaging tools, computed tomography (CT) can be very useful in diagnosing complications of the procedure, particularly in the subacute and delayed stages after ablation. This review illustrates CT imaging of several of the common and uncommon complications of radiofrequency catheter ablation

  13. Discogenic lumbar pain: association with MR imaging and CT discography

    International Nuclear Information System (INIS)

    Objective: To correlate MR and CT discography findings with pain response at provocative discography in patients with discogenic back pain. Materials and methods: Forty-seven patients aged 25-54 years who underwent MR imaging and subsequent CT discography (97 discs) were included in this study. MR images were retrospectively evaluated regarding disc degeneration, endplate abnormalities, facet joint osteoarthritis, and high intensity zone. During discography concordant pain was regarded as positive, whereas discordant pain and no pain were regarded as negative. MR and CT discographic findings were analyzed on the base of concordant pain using the Chi-square test. Results: Concordant pain was significantly common in the following (P < 0.05): grade 4 or 5 disc degeneration [88% (30/34) in concordant pain versus 48% (30/63) in discordant pain and no pain], high intensity zone [56% (19/34) versus 30% (19/63)], combination of above two findings [53% (18/34) versus 25% (16/63)], fissured and ruptured disc at discogram [94% (32/34) versus 57% (36/63)], and contrast beyond inner annulus at CT discogram [97% (33/34) versus 57% (36/63)]. Conclusion: Typical MR findings with concordant pain at discography include grade 4 or 5 disc degeneration and presence of a high intensity zone. Typical CT discography findings with concordant pain were fissured/ruptured discs and contrast extending into/beyond the outer annulus on CT

  14. PET/CT imaging in lung cancer: indications and findings

    Directory of Open Access Journals (Sweden)

    Bruno Hochhegger

    2015-06-01

    Full Text Available The use of PET/CT imaging in the work-up and management of patients with lung cancer has greatly increased in recent decades. The ability to combine functional and anatomical information has equipped PET/CT to look into various aspects of lung cancer, allowing more precise disease staging and providing useful data during the characterization of indeterminate pulmonary nodules. In addition, the accuracy of PET/CT has been shown to be greater than is that of conventional modalities in some scenarios, making PET/CT a valuable noninvasive method for the investigation of lung cancer. However, the interpretation of PET/CT findings presents numerous pitfalls and potential confounders. Therefore, it is imperative for pulmonologists and radiologists to familiarize themselves with the most relevant indications for and limitations of PET/CT, seeking to protect their patients from unnecessary radiation exposure and inappropriate treatment. This review article aimed to summarize the basic principles, indications, cancer staging considerations, and future applications related to the use of PET/CT in lung cancer.

  15. Cerebral infarction mimicking brain tumor on Tc-99m tetrofosmin brain SPECT imaging

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Soon [College of Medicine, Dongguk Univ., Gyeongju (Korea, Republic of); Zeon, Seok Kil; Won, Kyoung Sook [School of Medicine, Keimyung Univ., Daegu (Korea, Republic of)

    2004-06-01

    A 43-year-old man was presented with persistent headache for two weeks. T2 weighted MR imaging showed high signal intensity with surrounding edema in the left frontal lobe. These findings were considered with intracranial tumor such as glioma or metastasis. Tc-99m tetrofosmin SPECT showed focal radiotracer accumulation in the left frontal lobe. The operative specimen contained cerebral infarction with organizing leptomeningeal hematoma by pathologist. Another 73-year-old man was hospitalized for chronic headache. Initial CT showed ill-defined hypodensity with mass effect in the right parietal lobe. Tc-99m tetrofosmin SPECT showed focal radiotracer uptake in the right parietal lobe. These findings were considered with low-grade glioma or infarction. Follow-up CT after 5 months showed slightly decreased in size of low density in the right parietal lobe, and cerebral infarction is more likely than others. Tc-99m tetrofosmin has been proposed as a cardiotracer of myocardial perfusion imaging and an oncotropic radiotracer. Tc-99 tetrofosmin SPECT image provides a better attractive alternative agent than TI-201 as a tumor-imaging agent, with characteristics such as high-energy flux, short half-life, favorable biodistribution, dosimetry and lower background radioactivity. We have keep in mind on the analysis of Tc-99m tetrofosmin imaging when cerebral infarction is being differentiated from brain tumor.

  16. Use of segmented CT transmission map to avoid metal artifacts in PET images by a PET-CT device

    International Nuclear Information System (INIS)

    Background: Attenuation correction is generally used to PET images to achieve count rate values independent from tissue densities. The goal of this study was to provide a qualitative comparison of attenuation corrected PET images produced by a PET-CT device (CT, 120 kV, 40 mAs, FOV 600 mm) with and without segmentation of transmission data (ACseg+ and ACseg-respectively). Methods: The reconstructed images were compared to attenuation corrected images obtained with a high-energy transmission source (Cs-137 – 662 keV). Thirty oncologic patients were studied using CT and 137Cs for attenuation correction. All image data were acquired using the Gemini PET-CT scanner (Philips Medical Systems). It is an open PET-CT system that consists of the MX8000 multislice CT and the Allegro PET scanner arranged in a separable configuration. Images with ACseg+ and ACseg- were analyzed simultaneously in coronal, sagittal and transaxial planes. Two nuclear medicine physicians reviewed the image sets. Results: The image quality in the area of metal implants was better with ACseg+ than ACseg-, without metal induced artifacts generally observed in CT corrected images. Further the images with ACseg+ were qualitatively comparable to those obtained with 137Cs attenuation correction. Conclusions: In case of metal implants, PET studies corrected by CT should preferably use the ACseg+ method to avoid the image artifacts

  17. Magnetic resonance imaging of a brain abscess

    International Nuclear Information System (INIS)

    Magnetic resonance imaging (MRI) was performed on 13 patients with brain abscesses, and the alternation of MRI findings, as correlated with the progression of brain-abscess formation, was reviewed. In the cerebritis stage, spin-echo images showed a high intensity, and inversion-recovery images, a low intensity, due to inflammation and edema. The spin-echo images were very sensitive in delineating the brain edema; however, it was difficult to distinguish the inflammation from the surrounding edema. In the capsule stage, due to the accumulation of purulent material, the central necrotic area was demonstrated as a low-intensity area, while the capsule of the abscess was revealed as an iso-intensity ring on the inversion-recovery images. The central necrotic area also decreased in intensity on spin-echo images in the later period of this stage. With contrast enhancement (Gd-DTPA), the SR image showed the capsule as a high-intensity ring. MRI was found to be a useful method for estimating the process of the formation of a brain abscess. (author)

  18. Magnetic resonance imaging of a brain abscess

    Energy Technology Data Exchange (ETDEWEB)

    Oikawa, Akihiro; Kagawa, Mizuo; Yatoh, Seiji; Izawa, Masahiro; Ujiie, Hiroshi; Sakaguchi, Jun; Onda, Hideaki; Kitamura, Kohichi

    1988-06-01

    Magnetic resonance imaging (MRI) was performed on 13 patients with brain abscesses, and the alternation of MRI findings, as correlated with the progression of brain-abscess formation, was reviewed. In the cerebritis stage, spin-echo images showed a high intensity, and inversion-recovery images, a low intensity, due to inflammation and edema. The spin-echo images were very sensitive in delineating the brain edema; however, it was difficult to distinguish the inflammation from the surrounding edema. In the capsule stage, due to the accumulation of purulent material, the central necrotic area was demonstrated as a low-intensity area, while the capsule of the abscess was revealed as an iso-intensity ring on the inversion-recovery images. The central necrotic area also decreased in intensity on spin-echo images in the later period of this stage. With contrast enhancement (Gd-DTPA), the SR image showed the capsule as a high-intensity ring. MRI was found to be a useful method for estimating the process of the formation of a brain abscess.

  19. Experimental study of astrocytic swelling in rats and evaluation with CT perfusion imaging and histopathology

    International Nuclear Information System (INIS)

    Objective: To evaluate the influence of astrocytic swelling on regional cerebral blood flow. Methods: Sixteen male Wistar rats weighing from 280 g to 360 g were used. 1-aminocyclopentanetrans-1, 3-dicarboxylic acid (tACPD) was microinjected into the right caudatum. Brain water content was determined by a wet weight/dry weight technique. Dynamic CT perfusion imaging was achieved from personal computer aided mapping. Extravasation of Evan's blue (EB) into the brain was determined as an indicator of disturbance in the blood-brain barrier (BBB) and endothelial cells. Histopathologic examination by both light and electron microscopy was performed in 6 hours after injection surgery. Results: Brain edema was induced after tACPD injection and astrocytic swelling was showed in histopathologic examination. EB extravasation showed no blue stain, indicating no increase in BBB permeability induced by tACPD-injection. Electron microscope study confirmed this finding and revealed remarkable swelling of astrocytes, especially endfoot processes of astrocytes around capillaries at 6 h after tACPD-injection. The abnormal extent on CT perfusion images matched with abnormal extent on histopathologic examination. There were statistical significant differences between operated group and control group (P<0.05). Conclusion: Astrocytic swelling can induce or deteriorate the decrease of regional cerebral blood flow. The effectually remission of primary astrocytic swelling may provide new clues for the therapeutic intervention

  20. Radiation dose in cardiac CT angiography: Protocols and image quality

    International Nuclear Information System (INIS)

    This paper aims to evaluate the radiation dose exposure of patients submitted to cardiac computed tomography angiography. The effective dose was obtained from the product of dose-length product values and the conversion factor established in the European Working Group for Guidelines on Quality Criteria in CT. The image noise and contrast-and signal-to-noise ratios were obtained for all images. Sixty-four- and 256-slice CT angiographies were used in 211 (68.5 %) and 97 (31.5 %) patients, respectively. The calculated mean effective dose with prospective CT angiography was 6.0±1.0 mSv and the retrospective mode was 8.4±1.2 mSv. The mean image noise values were 38.5±9.5 and 21.4±5.3 for prospective and retrospective modes, respectively. It was observed that the image noise increased by 44.4 % using a prospective mode. Prospective CT angiography reduces radiation dose by ∼29 % compared with the retrospective mode, while maintaining diagnostic image quality and the ability to assess obstructions in patients. (authors)

  1. CEREBRAL HYDATID DISEASE: CT AND MR IMAGING FINDINGS

    Directory of Open Access Journals (Sweden)

    Ajay

    2014-10-01

    Full Text Available OBJECTIVE: Cerebral hydatid disease is very rare, representing only 2% of all cerebral space occupying lesions even in the countries where the disease is endemic. The aim of this paper is to describe the characteristic features of cerebral hydatid disease in computed tomography (CT and magnetic resonance imaging (MRI. METHODS: Here is a case 25yr/m who presented to neurosurgery OPD with complaints of headache, vomiting, right sided weakness and seizures for 2 weeks. CT and MRI were the imaging modalities to reach the diagnosis which was pathologically confirmed postoperatively as hydatid disease. RESULTS: CT and MR imaging findings of E. granulosus lesions were well defined, smooth thin-walled, spherical, homogeneous cystic lesions with no contrast enhancement, no calcification, and no surrounding oedema. CONCLUSION: Although cystic cerebral hydatid disease is well demonstrated by CT and MR examinations, CT is superior in detecting calcification in the cyst, when present, MR is better in demonstrating cyst capsule, detecting multiplicity and defining the anatomic relationship of the lesion with the adjacent structures, and it is more helpful in surgical planning.

  2. New frontiers in CT imaging of airway disease

    Energy Technology Data Exchange (ETDEWEB)

    Grenier, Philippe A.; Beigelman-Aubry, Catherine [Department of Radiology, University Pierre et Marie Curie, Paris (France); Fetita, Catalin; Preteux, Francoise [Institut National des Telecommunications, Department ARTEMIS, Evry (France); Brauner, Michel W. [Avicenne Hospital, UFR SMBH Paris XIII, Bobigny (France); Lenoir, Stephane [Institut Mutualiste Montsouris, Paris (France)

    2002-05-01

    Combining helical volumetric CT acquisition and thin-slice thickness during breath hold provides an accurate assessment of both focal and diffuse airway diseases. With multiple detector rows, compared with single-slice helical CT, multislice CT can cover a greater volume, during a simple breath hold, and with better longitudinal and in-plane spatial resolution and improved temporal resolution. The result in data set allows the generation of superior multiplanar and 3D images of the airways, including those obtained from techniques developed specifically for airway imaging, such as virtual bronchography and virtual bronchoscopy. Complementary CT evaluation at suspended or continuous full expiration is mandatory to detect air trapping that is a key finding for depicting an obstruction on the small airways. Indications for CT evaluation of the airways include: (a) detection of endobronchial lesions in patients with an unexplained hemoptysis; (b) evaluation of extent of tracheobronchial stenosis for planning treatment and follow-up; (c) detection of congenital airway anomalies revealed by hemoptysis or recurrent infection; (d) detection of postinfectious or postoperative airway fistula or dehiscence; and (e) diagnosis and assessment of extent of bronchiectasis and small airway disease. Improvement in image analysis technique and the use of spirometrically control of lung volume acquisition have made possible accurate and reproducible quantitative assessment of airway wall and lumen areas and lung density. This contributes to better insights in physiopathology of obstructive lung disease, particularly in chronic obstructive pulmonary disease and asthma. (orig.)

  3. Automated planning of breast radiotherapy using cone beam CT imaging

    Energy Technology Data Exchange (ETDEWEB)

    Amit, Guy [Radiation Medicine Program, Princess Margaret Cancer Centre, Toronto, Ontario M5G2M9 (Canada); Purdie, Thomas G., E-mail: tom.purdie@rmp.uhn.ca [Radiation Medicine Program, Princess Margaret Cancer Centre, Toronto, Ontario M5G2M9 (Canada); Department of Radiation Oncology, University of Toronto, Toronto, Ontario M5S 3E2 (Canada); Techna Institute, University Health Network, University of Toronto, Toronto, Ontario M5G 1P5 (Canada)

    2015-02-15

    Purpose: Develop and clinically validate a methodology for using cone beam computed tomography (CBCT) imaging in an automated treatment planning framework for breast IMRT. Methods: A technique for intensity correction of CBCT images was developed and evaluated. The technique is based on histogram matching of CBCT image sets, using information from “similar” planning CT image sets from a database of paired CBCT and CT image sets (n = 38). Automated treatment plans were generated for a testing subset (n = 15) on the planning CT and the corrected CBCT. The plans generated on the corrected CBCT were compared to the CT-based plans in terms of beam parameters, dosimetric indices, and dose distributions. Results: The corrected CBCT images showed considerable similarity to their corresponding planning CTs (average mutual information 1.0±0.1, average sum of absolute differences 185 ± 38). The automated CBCT-based plans were clinically acceptable, as well as equivalent to the CT-based plans with average gantry angle difference of 0.99°±1.1°, target volume overlap index (Dice) of 0.89±0.04 although with slightly higher maximum target doses (4482±90 vs 4560±84, P < 0.05). Gamma index analysis (3%, 3 mm) showed that the CBCT-based plans had the same dose distribution as plans calculated with the same beams on the registered planning CTs (average gamma index 0.12±0.04, gamma <1 in 99.4%±0.3%). Conclusions: The proposed method demonstrates the potential for a clinically feasible and efficient online adaptive breast IMRT planning method based on CBCT imaging, integrating automation.

  4. CT-diskography in patients with sciatica. Comparison with plain CT and MR imaging

    International Nuclear Information System (INIS)

    The findings at CT-diskography (CT-D), including recording of the pain introduced at contrast injection, were compared with plain CT and MR imaging in 111 disks in 101 patients aged 18 to 68 years. Six disks which were normal at CT had normal CT-D and 5 of them had normal signal on MR imaging. The degree of annular degeneration and the depth of the annular tears were significantly associated with each other and with loss of disk height, but not with size or location of the hernias. Only the depth of the tears was significantly associated with loss of signal on MR. However, frequently complete annular tears and severe annular degeneration were seen in association with small bulges and hernias, even in disks with normal or slightly reduced signal on MR and with normal height. The type and intensity of the pain introduced were associated with each other and with the depth of the annular tears, but not with the degree of annular degeneration, size of the hernia or the MR signal intensity of the disks. Annular degeneration and tears on one hand, and the type and intensity of pain introduced on the other, see to be related rather than separate phenomena. (orig./MG)

  5. Brain imaging, genetics and emotion

    NARCIS (Netherlands)

    Aleman, Andre; Swart, Marte; van Rijn, Sophie

    2008-01-01

    This paper reviews the published evidence on genetically driven variation in neurotransmitter function and brain circuits involved in emotion. Several studies point to a role of the serotonin transporter promoter polymorphism in amygdala activation during emotion perception. We also discuss other po

  6. The study of CT pulmonary functional imaging technique

    International Nuclear Information System (INIS)

    Objective: To evaluate the feasibility of CT pulmonary function imaging with emphasis on the results of the correlation between CT functional imaging parameters and that of pulmonary functional tests. Methods: The study population was 69 cases. According to the results of pulmonary functional tests (PFT), 21 persons with normal lung function, 37 patients with obstructive lung function abnormality, 9 with restrictive lung function abnormality, and 2 with mixed lung function abnormality were included. The CT scanning and pulmonary function tests were performed within one week for all of the cases. Spiral CT scans were obtained during breath hold at full inspiration and full expiration from the lung bases to the lung apices. The scanning parameters were as fellows: 120 kV, 175 mA, one revolution per second; 10 mm slice thickness; 20 mm/s table speed (pitch 2). The images were reconstructed by 10 mm slice thickness and standard algorithm, and then were archived and transferred digitally to personal computer for analysis. A CT pulmonary functional quantitative software designed by the authors was used to analysis all images. Results: Using full inspiratory and expirator spiral CT, total lung capacity (Vin) and residual capacity (Vex) were revealed, which had a good correlation with results obtained by pulmonary function tests (r = 0.866, P < 0.001; r = 0.833, P < 0.001). Vex/Vin showed correlation with RV/TLC (r = 0.590, P < 0.001). The mean lung CT value obtained at full inspiratory phase showed correlation with FEV 1%, FEV1/FVC (r = 0.382, P < 0.05; r = 0.682, P < 0.01). PI = -910- -950 HU were found to correlate with FEV1, FEV1%, FVC%, FEV1/FVC, especially to have good correlation with FEV1/FVC (r = 0.747 - 0.772, P < 0.01). The mean lung CT value obtained at full expiratory phase also showed correlation with FEV1, FEV1%, FVC%, FEV1/FVC (r = 0.624, P < 0.01; r = 0.654, P < 0.01; r = 0.452, P < 0.01; r = 0.758, P < 0.01); Several pixel index (PI) at expiratory also

  7. Low-dose spiral CT: applicability to paediatric chest imaging

    Energy Technology Data Exchange (ETDEWEB)

    Rogalla, P.; Stoever, B.; Scheer, I.; Juran, R.; Hamm, B. (Department of Diagnostic and Interventional Radiology, Humboldt-Univ. Berlin (Germany)); Gaedicke, G. (Department of Pediatrics, Humboldt-Univ., Berlin (Germany))

    1999-08-01

    Background. Spiral CT of the chest is an imaging technique with unequivocal indications and proven higher sensitivity and specificity than conventional chest X-rays. However, particularly in children, attempts should be made to reduce radiation exposure to a minimum. Objective. To evaluate whether a low-dose technique in spiral CT scanning results in adequate diagnostic information. Materials and methods. In a prospective study, 27 children (range 3 weeks to 14 years, mean 7 years) underwent a low-dose CT examination of the chest for various indications. The tube energy was 12.5 mAs (n = 5), 25 mAs (n = 17), 50 mAs (n = 3), or 75 mAs (n = 2) per slice. Two radiologists evaluated, in consensus, the CT scans with respect to their diagnostic value and comparison was made with 20 standard-dose chest CT examinations of adults (175 mAs per slice, mean age 56 years) with respect to technical image quality (noise and artefacts). In a second part of the study, dose measurements were carried out by means of exposing thermoluminescent dosimeters attached to a water/air phantom simulating a child's chest. Results. All low-dose CT scans were of diagnostic image quality and no additional studies were necessary. The average image noise was significantly higher than in standard-dose CT examinations (SD 39.5 compared with 12.5 for unenhanced soft tissue, P < 0.01), but did not hinder accurate diagnosis. Artefacts were exclusively due to patient motion. Radiation exposure per slice was approx. 4 mGy at 25 mAs and 34 mGy at 250 mAs, regardless of slice thickness. Conclusions. For all indications in paediatric CT scanning of the chest, low-dose technique provides adequate image quality without loss of diagnostic information. The radiation exposure is approximately 5-20 % of a standard-dose CT. (orig.) With 3 figs., 1 tab., 17 refs.

  8. Comparison of patient positioning between using fluoroscopy image and using CT image

    International Nuclear Information System (INIS)

    To improve the accuracy of patient positioning, two medical imaging modalities were compared. One was a fluoroscopy (x-ray TV) image, which has been using the patient positioning at heavy ion medical accelerator in Chiba (HIMAC) routinely. The x-ray TV method was based on the comparison of anatomical bone structure between the reference image and the positioning image. However the identification of organ position from x-ray TV image was difficult. Therefore this method didn't directly detect the inter-fraction organ motion. Another modality was CT image. The CT image for positioning was directly compared to treatment planning CT images and was easy to identify the inter-fraction organ motion. In our study of CT positioning it was possible to detect three-dimensional positioning error in high precision. But CT scanner was so large that the beam-port nozzle interfered with CT scanner. In this paper we mentioned the present X-ray TV positioning at HIMAC, and considered merits and demerit of CT positioning. (author)

  9. Proton MRS imaging in pediatric brain tumors.

    Science.gov (United States)

    Zarifi, Maria; Tzika, A Aria

    2016-06-01

    Magnetic resonance (MR) techniques offer a noninvasive, non-irradiating yet sensitive approach to diagnosing and monitoring pediatric brain tumors. Proton MR spectroscopy (MRS), as an adjunct to MRI, is being more widely applied to monitor the metabolic aspects of brain cancer. In vivo MRS biomarkers represent a promising advance and may influence treatment choice at both initial diagnosis and follow-up, given the inherent difficulties of sequential biopsies to monitor therapeutic response. When combined with anatomical or other types of imaging, MRS provides unique information regarding biochemistry in inoperable brain tumors and can complement neuropathological data, guide biopsies and enhance insight into therapeutic options. The combination of noninvasively acquired prognostic information and the high-resolution anatomical imaging provided by conventional MRI is expected to surpass molecular analysis and DNA microarray gene profiling, both of which, although promising, depend on invasive biopsy. This review focuses on recent data in the field of MRS in children with brain tumors. PMID:27233788

  10. NMR imaging of the brain: initial impressions

    International Nuclear Information System (INIS)

    An NMR imaging system designed and built by Thorn-EMI Ltd was installed at Hammersmith Hospital in March 1981. In the first year of operation 180 patients and 40 volunteers have had cranial examinations and initial impressions bases on this experience are presented. Patients with a wide variety of neurological diseases have been studied to provide a basis for diagnostic interpretation, to define distinctive features, and to evaluate different types of scanning sequences. NMR imaging appears to be of considerable value in neurological diagnosis and has a number of advantages over CT. The detailed evaluation of NMR imaging will require much more work but the initial results are very promising

  11. Construction of a voxel model from CT images with density derived from CT numbers

    International Nuclear Information System (INIS)

    The voxel models representing human anatomy have been developed to calculate dose distribution in human body, while the density is the most important physical property of voxel model. Traditionally, when creating the Monte Carlo input files, the average tissue parameters recommended in ICRP report were used to assign each voxel in the existing voxel models. However, as each tissue consists of many voxels in which voxels are different in their densities, the method of assigning average tissue parameters doesn't take account of the voxel's discrepancy, and can't represent human anatomy faithfully. To represent human anatomy more faithfully, a method was implemented to assign each voxel, the density of which was derived from CT number. In order to compare with the traditional method, we have constructed two models from a same cadaver specimen date set. A CT-based pelvic voxel model called Pelvis-CT model, was constructed, the densities of which were derived from the CT numbers. A color photograph-based pelvic voxel model called Pelvis-Photo model, was also constructed, the densities of which were taken from ICRP Publication. The CT images and color photographs were obtained from the same female cadaver specimen. The Pelvis-CT and Pelvis-Photo models were ported into Monte Carlo code MCNP to calculate the conversion coefficients from kerma free-in-air to absorbed dose for external monoenergetic photon beams with energies of 0.1, 1 and 10 MeV under anterior-posterior (AP) geometries. The results were compared with those of given in ICRP74. Differences of up to 50% were observed between conversion coefficients of Pelvis-CT and Pelvis-Photo models, moreover the discrepancies decreased for the photon beams with higher energies. The overall trend of conversion coefficients of the Pelvis-CT model were agreed well with that of ICRP74 data. (author)

  12. Recent advances in imaging of brain tumors

    OpenAIRE

    D A Sanghvi

    2009-01-01

    The recent advances in brain tumor imaging offer unique anatomical as well as pathophysiological information that provides new insights on brain tumors, directed at facilitating therapeutic decisions and providing information regarding prognosis. This information is presently utilized in clinical practice for initial diagnosis and noninvasive, preoperative grading of tumors, biopsy planning, surgery, and radiation portal planning, as well as, prognostication. The newer advances described in t...

  13. Optical crosstalk in CT detectors and its effects on CT images

    Science.gov (United States)

    Youn, Hanbean; Kam, Soohwa; Han, Jong Chul; Kim, Ho Kyung

    2014-03-01

    Detectors for computed tomography (CT) typically consist of scintillator and photodiode arrays which are coupled using optical glue. Therefore, the leakage of optical photons generated in a scintillator block to neighboring pixel photodiodes through the optical glue layer is inevitable. Passivation layers to protect the silicon photodiode as well as the silicon layer itself, which is inactive to the optical photons, are another causes for the leakage. This optical crosstalk reduces image sharpness, and eventually will blur CT images. We have quantitatively investigated the optical crosstalk in CT detectors using the Monte Carlo technique. We performed the optical Monte Carlo simulations for various thicknesses of optical components in a 129 × 129 CT detector array. We obtained the coordinates of optical photons hitting the user-defined detection plane. From the coordinate information, we calculated the collection efficiency at the detection plane and the collection efficiency at the single pixel located just below the scintillator in which the optical photons were generated. Difference between the two quantities provided the optical crosstalk. In addition, using the coordinate information, we calculated point-spread functions as well as modulation-transfer functions from which we estimated the effective aperture due to the optical photon spreading. The optical crosstalk was most severely affected by the thickness of photodiode passivation layer. The effective aperture due to the optical crosstalk was about 110% of the detector pixel aperture for a 0.1 mm-thick passivation layer, and this signal blur was appeared as a relative error of about 3-4% in mismatches between CT images with and without the optical crosstalk. The detailed simulation results are shown and will be very useful for the design of CT detectors.

  14. 3D imaging of aortic aneurysma using spiral CT

    International Nuclear Information System (INIS)

    The use of 3D reconstructions (3D display technique and maximum intensity projection) in spiral CT for diagnostic evaluation of aortic aneurysma is explained. The data available showing 12 aneurysma of the abdominal and thoracic aorta (10 cases of aneurysma verum, 2 cases of aneurysma dissecans) were selected for verification of the value of 3D images in comparison to transversal displays of the CT. The 3D reconstructions of the spiral CT, other than the projection angiography, give insight into the vessel from various points of view. Such information is helpful for quickly gathering a picture of the volume and contours of a pathological process in the vessel. 3D post-processing of data is advisable if the comparison of tomograms and projection images produces findings of nuclear definition which need clarification prior to surgery. (orig.)

  15. Peritoneal Lymphomatosis Imaged by F-18 FDG PET/CT

    Energy Technology Data Exchange (ETDEWEB)

    Park, Eun Kyung; Lee, Se Ryeon; Kim, Young Chul; Oh, Sun Young; Choe, Jae Gol [Korea University Anam Hospital, Seoul (Korea, Republic of)

    2010-06-15

    Peritoneal lymphomatosis is uncommon, but when encountered is associated with aggressive histological subtypes of high-grade lymphoma, such as small-cell, large-cell, mixed large and small cell, non-cleaved, lymphoblastic Burkitt-like, and diffuse large B-cell lymphomas. The CT findings of peritoneal lymphomatosis are linear or nodular peritoneal thickening, retroperitoneal lymphadenopathy, omental and mesenteric involvement with streak-like infiltrations or a bulky mass, bowel wall thickening, hepatosplenomegaly, and ascites. The authors reports report the first FDG PET/CT images of diffuse large B-cell lymphoma of small bowel origin associated with peritoneal lymphomatosis in a 69-year-old man. The lesions demonstrated intense FDG uptake in PET/CT images.

  16. Peritoneal Lymphomatosis Imaged by F-18 FDG PET/CT

    International Nuclear Information System (INIS)

    Peritoneal lymphomatosis is uncommon, but when encountered is associated with aggressive histological subtypes of high-grade lymphoma, such as small-cell, large-cell, mixed large and small cell, non-cleaved, lymphoblastic Burkitt-like, and diffuse large B-cell lymphomas. The CT findings of peritoneal lymphomatosis are linear or nodular peritoneal thickening, retroperitoneal lymphadenopathy, omental and mesenteric involvement with streak-like infiltrations or a bulky mass, bowel wall thickening, hepatosplenomegaly, and ascites. The authors reports report the first FDG PET/CT images of diffuse large B-cell lymphoma of small bowel origin associated with peritoneal lymphomatosis in a 69-year-old man. The lesions demonstrated intense FDG uptake in PET/CT images.

  17. Generating text from functional brain images

    Directory of Open Access Journals (Sweden)

    Francisco ePereira

    2011-08-01

    Full Text Available Recent work has shown that it is possible to take brain images acquired during viewing of a scene and reconstruct an approximation of the scene from those images. Here we show that it is also possible to generate text about the mental content reflected in brain images. We began with images collected as participants read names of concrete items (e.g., "Apartment" while also seeing line drawings of the item named. We built a model of the mental semantic representation of concrete concepts from text data and learned to map aspects of such representation to patterns of activation in the corresponding brain image. In order to validate this mapping, without accessing information about the items viewed for left-out individual brain images, we were able to generate from each one a collection of semantically pertinent words (e.g., "door," "window" for "Apartment". Furthermore, we show that the ability to generate such words allows us to perform a classification task and thus validate our method quantitatively.

  18. MR imaging of regional late brain development

    International Nuclear Information System (INIS)

    This paper reports, to complement current knowledge on brain development, late regional brain maturation assessed with quantitative MR imaging. Axial and coronal head spin-echo (SE) images were obtained in 60 healthy individuals aged 5--56 years, with a double-echo, flow compensated imaging sequence obtained with a 1.5-T Magnetom spectroscopy and imaging system. T2-weighted images were calculated from the intensity differences in SE images at echo times (TEs) of 15 and 90 msec (TR = 2.5 second). The mean T2 values were determined at 16 sites in each cerebral hemisphere. T2 values of the six frontal subcortical white matter (FSCWM) sites and of the internal capsule (IC) were evaluated. Mean T2 values in the IC decreased until age 10 years, whereas this decrease continued in the FSCWM past age 15 years before reaching a plateau. Differential age-dependent patterns of mean T2 values emerged between the six FSCWM sites. The spread of T2 values varied at different sites independent of the age of the individuals. T2- values have previously been shown to reflect the status of brain development. The authors' data on the six FSCWM sites and the IC extend these findings to specific substructures of the brain. Interindividual variations and technical issues are responsible for the observed spread of data

  19. Multimodal imaging of orthotopic hepatocellular carcinoma using small animal PET, bioluminescence and contrast enhanced CT imaging

    International Nuclear Information System (INIS)

    Molecular imaging with small-animal PET and bioluminescence imaging has been used as an important tool in cancer research. One of the disadvantages of these imaging modalities is the lack of anatomic information. To obtain fusion images with both molecular and anatomical information, small-animal PET and bioluminescence images fused with contrast enhance CT image in orthotopic hepatocellular carcinoma (HCC) model. We retrovially transfected dual gene (HSV1-tk and firefly luciferase) to morris hepatoma cells. The expression of HSV1-tk and luciferase was checked by optical imager and in vitro radiolabeled FIAU uptake, respectively and also checked by RT-PCR analysis. MCA-TL cells (5X105/ 0.05 ml) mixed with matrigel (1: 10) injected into left lobe of liver in nude mice. 124I-FIAU-PET, bioluminescence and contrast enhanced CT images were obtained in the orthotopic HCC model and digital whole body autoradiography (DWBA) was performed. Small animal PET image was obtained at 2 h post injection of 124I-FIAU and contrast enhanced CT image was obtained at 3 h post injection of Fenestra LC (0.3 ml). MCA-TL cells showed more specific 124I-FIAU uptake and higher luminescent activity than parental cells. The orthotopic HCC was detected by 124I-FIAU PET, contrast enhanced CT, and BLI and confirmed by DWBA. Registered image in orthotopic HCC t models showed a good correlation of images from both PET and CT. Contrast enhanced CT image delineated margin of HCC. Multimodal imaging with 124I-FIAU PET, bioluminescence and contrast enhanced CT allows a precise and improved detection of tumor in orthotopic hepatocellular carcinoma model. Multimodal imaging is potentially useful for monitoring progression of hepatic metastasis and for the evaluation of cancer treatments

  20. Spectrum of brain abnormalities detected on whole body 18F FDG PET/CT in patients undergoing evaluation for non-CNS malignancies

    International Nuclear Information System (INIS)

    We present the pattern of metabolic brain abnormalities detected in patients undergoing whole body (WB) 18F flurodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) examination for non-central nervous system (CNS) malignancies. Knowledge of the PET/CT appearance of various intracranial metabolic abnormalities enables correct interpretation of PET scans in oncological patients where differentiation of metastasis from benign intracranial pathologies is important and improves specificity of the PET study. A complete clinical history and correlation with CT and MRI greatly helps in arriving at a correct imaging diagnosis. (author)

  1. Methylmalonic acidemia: brain imaging findings in 52 children and a review of the literature

    International Nuclear Information System (INIS)

    Methylmalonic acidemia (MMA) is an autosomal-recessive inborn error of metabolism. To recognize the CT and MR brain sectional imaging findings in children with MMA. Brain imaging studies (47 MR and 5 CT studies) from 52 children were reviewed and reported by a neuroradiologist. The clinical data were collected for each patient. The most common findings were ventricular dilation (17 studies), cortical atrophy (15), periventricular white matter abnormality (12), thinning of the corpus callosum (8), subcortical white matter abnormality (6), cerebellar atrophy (4), basal ganglionic calcification (3), and myelination delay (3). The brain images in 14 patients were normal. Radiological findings of MMA are nonspecific. A constellation of common clinical and radiological findings should raise the suspicion of MMA. (orig.)

  2. Methylmalonic acidemia: brain imaging findings in 52 children and a review of the literature

    Energy Technology Data Exchange (ETDEWEB)

    Radmanesh, Alireza [Brigham and Women' s Hospital, Harvard Medical School, Department of Radiology, Boston, MA (United States); Zaman, Talieh [Tehran University of Medical Sciences, Department of Pediatric Metabolic Disorders, Tehran (Iran); Ghanaati, Hossein [Tehran University of Medical Sciences, Department of Radiology, Tehran (Iran); Molaei, Sanaz [Shahid Beheshti University of Medical Sciences, Department of Radiology, Tehran (Iran); Robertson, Richard L. [Children' s Hospital Boston, Department of Radiology, Boston, MA (United States); Zamani, Amir A. [Harvard Medical School, Department of Radiology, Brigham and Women' s Hospital, Boston, MA (United States)

    2008-10-15

    Methylmalonic acidemia (MMA) is an autosomal-recessive inborn error of metabolism. To recognize the CT and MR brain sectional imaging findings in children with MMA. Brain imaging studies (47 MR and 5 CT studies) from 52 children were reviewed and reported by a neuroradiologist. The clinical data were collected for each patient. The most common findings were ventricular dilation (17 studies), cortical atrophy (15), periventricular white matter abnormality (12), thinning of the corpus callosum (8), subcortical white matter abnormality (6), cerebellar atrophy (4), basal ganglionic calcification (3), and myelination delay (3). The brain images in 14 patients were normal. Radiological findings of MMA are nonspecific. A constellation of common clinical and radiological findings should raise the suspicion of MMA. (orig.)

  3. Four-view spect brain imaging detector

    International Nuclear Information System (INIS)

    This paper reports that with increasing use of single photon radiopharmaceuticals for brain imaging, there is a growing demand for efficient, economical SPECT brain imaging instrumentation. This new multiple view imaging detector design has the sensitivity advantages of an array of four discrete cameras, but functions essentially like a single camera head. Four separate flat crystals are surrounded with PMT's which perform as a single array for photon event detection. Unique windows on adjoining crystal edges are coupled to corner light pipe/PMT assemblies. Reduced edge packing range, and sharing of corner PMT's allows a compact assembly volume, even with 3 inch PMT's. The imaging volume is approximately a 23 centimeter cube, and the imaging electronics are nearly the same as used in a single 64 PMT gamma camera

  4. CT dose and image quality studies using phantom and clinical images: the dose efficiency index

    International Nuclear Information System (INIS)

    As part of the effort in reducing radiation dose to patients, the selection of a radiation dose efficient CT scanner is vital from the clinical practice point of view. A number of CT dose efficiency indexes have been suggested in the literature for the assessment of the CT scanners from different manufactures. There is still no generally accepted index or figure of merit for the assessment of CT scanners. In this work, CT phantom and clinical images were acquired or collected from a number of clinical imaging centres using both 16 and 64 slices scanners of the four major CT manufactures. CT dose was displayed as CTDI on the images and image quality was assessed by four human observers and ranked using 1.5 visual grading scale. The best fit for the relationship between the dose and image quality is an exponential function and a new dose efficiency index is defined as the radio of the image quality to radiation dose at the just acceptable image quality for diagnosis.

  5. Computer aided detection of oral lesions on CT images

    International Nuclear Information System (INIS)

    Oral lesions are important findings on computed tomography (CT) images. In this study, a fully automatic method to detect oral lesions in mandibular region from dental CT images is proposed. Two methods were developed to recognize two types of lesions namely (1) Close border (CB) lesions and (2) Open border (OB) lesions, which cover most of the lesion types that can be found on CT images. For the detection of CB lesions, fifteen features were extracted from each initial lesion candidates and multi layer perceptron (MLP) neural network was used to classify suspicious regions. Moreover, OB lesions were detected using a rule based image processing method, where no feature extraction or classification algorithm were used. The results were validated using a CT dataset of 52 patients, where 22 patients had abnormalities and 30 patients were normal. Using non-training dataset, CB detection algorithm yielded 71% sensitivity with 0.31 false positives per patient. Furthermore, OB detection algorithm achieved 100% sensitivity with 0.13 false positives per patient. Results suggest that, the proposed framework, which consists of two methods, has the potential to be used in clinical context, and assist radiologists for better diagnosis

  6. Computer aided detection of oral lesions on CT images

    Science.gov (United States)

    Galib, S.; Islam, F.; Abir, M.; Lee, H. K.

    2015-12-01

    Oral lesions are important findings on computed tomography (CT) images. In this study, a fully automatic method to detect oral lesions in mandibular region from dental CT images is proposed. Two methods were developed to recognize two types of lesions namely (1) Close border (CB) lesions and (2) Open border (OB) lesions, which cover most of the lesion types that can be found on CT images. For the detection of CB lesions, fifteen features were extracted from each initial lesion candidates and multi layer perceptron (MLP) neural network was used to classify suspicious regions. Moreover, OB lesions were detected using a rule based image processing method, where no feature extraction or classification algorithm were used. The results were validated using a CT dataset of 52 patients, where 22 patients had abnormalities and 30 patients were normal. Using non-training dataset, CB detection algorithm yielded 71% sensitivity with 0.31 false positives per patient. Furthermore, OB detection algorithm achieved 100% sensitivity with 0.13 false positives per patient. Results suggest that, the proposed framework, which consists of two methods, has the potential to be used in clinical context, and assist radiologists for better diagnosis.

  7. 多层螺旋 CT 灌注成像在脑胶质瘤分级中的价值与微血管密度的相关性研究%Application value of multi-slice spiral CT perfusion imaging in brain gliomas and its relation with microvessel density

    Institute of Scientific and Technical Information of China (English)

    洪建斌; 许乃滔; 侯志雄

    2014-01-01

    Objective To study the value of multi-slice spiral CT (MSCT ) perfusion imaging in grading of brain glioma(BG) and its correlation with microvessel density (MVD) .Methods A total of 89 BG patients ,treated in this hospital from March 2010 to March 2013 ,were enrolled and divided into high grade group and low grade group , according to the grading levels .MSCT parameters and MVD ,vascular endothelial growth factor(VEGF) levels were compared ,and the correlation between relative cerebral blood flow (rCBV) and MVD ,VEGF were analyzed .Results Levels of cerebral blood flow (CBF) ,rCBF ,cerebral blood volume(CBV) ,relative CBV(rCBV) of high grade group were significantly higher than low grade group (P< 0 .05) .The positive rate of VEGF in high grade group was 89 .13% (41/46) ,higher than the 55 .81% (24/43) of low grade group(P<0 .05) .Level of MVD in high grade group was 70 .76 ± 8 .85 ,significantly higher than the 37 .75 ± 5 .65 of low grade group(P<0 .05) .rCBV level was positive-ly correlated with MVD and VEGF expression level (r= 0 .610 and r= 0 .631 ,P< 0 .05) .Conclusion rCBV level could be positively correlated with MVD and VEGF expression level in patients wit BG .MSCT could provide fine im-aging evidence for the grading of BG .%目的:研究多层螺旋CT(MSCT)灌注成像在脑胶质瘤(BG)分级中的价值与微血管密度(MVD)的相关性。方法选择该院2010年3月至2013年3月诊治的89例BG患者作为观察对象,根据BG分级标准分成高级别组以及低级别组。对比两组MSCT参数以及MVD、血管内皮生长因子(VEGF);分析相对脑血容量(rCBV)和MVD、VEGF的相关性。结果高级别组的脑血流量(CBF)、相对脑血流量(rCBF)、脑血容量(CBV)、rCBV均明显高于低级别组;高级别组VEGF阳性率为89.13%(41/46),明显高于低级别组的55.81%(24/43);高级别组MVD为70.76±8.85,明显高于低级别组的37.75±5.65,差

  8. Early initiation of prophylactic heparin in severe traumatic brain injury is associated with accelerated improvement on brain imaging

    Directory of Open Access Journals (Sweden)

    Luke Kim

    2014-01-01

    Full Text Available Background: Venous thromboembolic prophylaxis (VTEp is often delayed following traumatic brain injury (TBI, yet animal data suggest that it may reduce cerebral inflammation and improve cognitive recovery. We hypothesized that earlier VTEp initiation in severe TBI patients would result in more rapid neurologic recovery and reduced progression of brain injury on radiologic imaging. Study Design: Medical charts of severe TBI patients admitted to a level 1 trauma center in 2009-2010 were queried for admission Glasgow Coma Scale (GCS, head Abbreviated Injury Scale, Injury Severity Score (ISS, osmotherapy use, emergency neurosurgery, and delay to VTEp initiation. Progression (+1 = better, 0 = no change, −1 = worse of brain injury on head CTs and neurologic exam (by bedside MD, nurse was collected from patient charts. Head CT scan Marshall scores were calculated from the initial head CT results. Results: A total of 22, 34, and 19 patients received VTEp at early (5 days time intervals, respectively. Clinical and radiologic brain injury characteristics on admission were similar among the three groups (P > 0.05, but ISS was greatest in the early group (P < 0.05. Initial head CT Marshall scores were similar in early and late groups. The slowest progression of brain injury on repeated head CT scans was in the early VTEp group up to 10 days after admission. Conclusion: Early initiation of prophylactic heparin in severe TBI is not associated with deterioration neurologic exam and may result in less progression of injury on brain imaging. Possible neuroprotective effects of heparin in humans need further investigation.

  9. Small cell carcinoma of the urinary bladder: CT and MR imaging findings

    International Nuclear Information System (INIS)

    Primary small cell carcinoma (SCC) is a rare aggressive malignancy of the urinary bladder, with identical histopathology to that of the lung. The treatment and prognosis of bladder SCC are somewhat different from those of more frequent transitional cell carcinoma. The purpose of this study was to analyze the CT and MR imaging findings of bladder SCC. Six adult patients (five males and one female) with pathologically proven SCC of the urinary bladder who had undergone pelvic CT and/or MR imaging were included in this study. The radiologic findings were retrospectively evaluated in terms of tumor location, texture, calcification, depth of invasion, perivesical extension, lymph node involvement, and local or distant metastasis, by two radiologists, who established a consensus. CT and MR images depicted all tumors as large, ill-defined, relatively well enhancing, broad-based polypoid intramural masses with (n=3) or without (n=3) cystic portions. Their frequent location was posterior and trigonal (n=3). Calcification was found within one tumor, and lymphadenopathy in four. At T2- weighted MR images, the solid portion of the tumor was relatively hypointense. The stage at the time of diagnosis was C in three patients, and D1 in three. Follow-up imaging showed brain metastasis in one patient and liver metastasis in two. On CT and MR images, SCC of the urinary bladder appeared as a large, enhancing, broad-based polypoid mass. It was stage C or higher, and lymph nodes and distant metastasis were frequent. T2-weighted MR images showed that the solid portion of the tumor was relatively hypointense. When radiologic examinations demonstrate a bladder tumor of this kind in adults, SCC of the urinary bladder should be included in the differential diagnosis

  10. Small cell carcinoma of the urinary bladder: CT and MR imaging findings

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jong Chul [Chungnam National University School of Medicine, Taejon (Korea, Republic of); Kim, Kie Hwan [Korea Cancer Center Hospital, Seoul (Korea, Republic of); Jung, Seungeun [Catholic University Medical College, Seoul (Korea, Republic of)

    2003-06-01

    Primary small cell carcinoma (SCC) is a rare aggressive malignancy of the urinary bladder, with identical histopathology to that of the lung. The treatment and prognosis of bladder SCC are somewhat different from those of more frequent transitional cell carcinoma. The purpose of this study was to analyze the CT and MR imaging findings of bladder SCC. Six adult patients (five males and one female) with pathologically proven SCC of the urinary bladder who had undergone pelvic CT and/or MR imaging were included in this study. The radiologic findings were retrospectively evaluated in terms of tumor location, texture, calcification, depth of invasion, perivesical extension, lymph node involvement, and local or distant metastasis, by two radiologists, who established a consensus. CT and MR images depicted all tumors as large, ill-defined, relatively well enhancing, broad-based polypoid intramural masses with (n=3) or without (n=3) cystic portions. Their frequent location was posterior and trigonal (n=3). Calcification was found within one tumor, and lymphadenopathy in four. At T2- weighted MR images, the solid portion of the tumor was relatively hypointense. The stage at the time of diagnosis was C in three patients, and D1 in three. Follow-up imaging showed brain metastasis in one patient and liver metastasis in two. On CT and MR images, SCC of the urinary bladder appeared as a large, enhancing, broad-based polypoid mass. It was stage C or higher, and lymph nodes and distant metastasis were frequent. T2-weighted MR images showed that the solid portion of the tumor was relatively hypointense. When radiologic examinations demonstrate a bladder tumor of this kind in adults, SCC of the urinary bladder should be included in the differential diagnosis.

  11. Interhospital CT image communication: T-1 line versus courier service

    Science.gov (United States)

    Lou, Shyhliang A.; Huang, H. K.; Bazzill, Todd M.; Gould, Robert G.; Dillon, William P.; Schomer, Barbara G.

    1995-05-01

    The Mount Zion Hospital (MZH) in San Francisco, Calif. is associated with the University of California at San Francisco (UCSF) medical center. These hospitals are approximately two miles apart. The UCSF radiology department supports specialty image reading for MZH daily. The major issue involved with this service is the access of patient images. Currently, the patient image access is through two ways: (1) inter-hospital travel, and (2) image delivery. Both methods are neither efficient nor economic. If patient images can be transferred from MZH to UCSF to be viewed in digital form in a reasonable time period, the issue of patient image accession can be resolved. This study attempts to use an available digital communication technology, a T-1 line, to verify this hypothesis. The study is centered on the comparison between the T-1 line and courier service with respect to cost and image delivery performance. This comparison study focuses on CT images with an emphasis on neuroradiology application.

  12. Brain 'imaging' in the Renaissance.

    Science.gov (United States)

    Paluzzi, Alessandro; Belli, Antonio; Bain, Peter; Viva, Laura

    2007-12-01

    During the Renaissance, a period of 'rebirth' for humanities and science, new knowledge and speculation began to emerge about the function of the human body, replacing ancient religious and philosophical dogma. The brain must have been a fascinating mystery to a Renaissance artist, but some speculation existed at that time on the function of its parts. Here we show how revived interest in anatomy and life sciences may have influenced the figurative work of Italian and Flemish masters, such as Rafael, Michelangelo and David. We present a historical perspective on the artists and the period in which they lived, their fascination for human anatomy and its symbolic use in their art. Prior to the 16th century, knowledge of the brain was limited and influenced in a dogmatic way by the teachings of Galen(1) who, as we now know, conducted his anatomical studies not on humans but on animals.(2) Nemesus, Bishop of Emesa, in around the year 400 was one of the first to attribute mental faculties to the brain, specifically to the ventricles. He identified two anterior (lateral) ventricles, to which he assigned perception, a middle ventricle responsible for cognition and a posterior ventricle for memory.(2,3) After a long period of stasis in the Middle Ages, Renaissance scholars realized the importance of making direct observations on dissected cadavers. Between 1504 and 1507, Leonardo da Vinci conducted experiments to reveal the anatomy of the ventricular system in the brain. He injected hot wax through a tube thrust into the ventricular cavities of an ox and then scraped the overlying brain off, thus obtaining, in a simple but ingenious way, an accurate cast of the ventricles.(2,4) Leonardo shared the belief promoted by scholarly Christians that the ventricles were the abode of rational soul. We have several examples of hidden symbolism in Renaissance paintings, but the influence of phrenology and this rudimentary knowledge of neuroanatomy on artists of that period is under

  13. Organ dose calculation in CT based on scout image data and automatic image registration

    Energy Technology Data Exchange (ETDEWEB)

    Kortesniemi, Mika; Salli, Eero; Seuri, Raija [HUS Helsinki Medical Imaging Center, Univ. of Helsinki, Helsinki (Finland)], E-mail: mika.kortesniemi@hus.fi

    2012-10-15

    Background Computed tomography (CT) has become the main contributor of the cumulative radiation exposure in radiology. Information on cumulative exposure history of the patient should be available for efficient management of radiation exposures and for radiological justification. Purpose To develop and evaluate automatic image registration for organ dose calculation in CT. Material and Methods Planning radiograph (scout) image data describing CT scan ranges from 15 thoracic CT examinations (9 men and 6 women) and 10 abdominal CT examinations (6 men and 4 women) were co-registered with the reference trunk CT scout image. 2-D affine transformation and normalized correlation metric was used for image registration. Longitudinal (z-axis) scan range coordinates on the reference scout image were converted into slice locations on the CT-Expo anthropomorphic male and female models, following organ and effective dose calculations. Results The average deviation of z-location of studied patient images from the corresponding location in the reference scout image was 6.2 mm. The ranges of organ and effective doses with constant exposure parameters were from 0 to 28.0 mGy and from 7.3 to 14.5 mSv, respectively. The mean deviation of the doses for fully irradiated organs (inside the scan range), partially irradiated organs and non-irradiated organs (outside the scan range) was 1%, 5%, and 22%, respectively, due to image registration. Conclusion The automated image processing method to registrate individual chest and abdominal CT scout radiograph with the reference scout radiograph is feasible. It can be used to determine the individual scan range coordinates in z-direction to calculate the organ dose values. The presented method could be utilized in automatic organ dose calculation in CT for radiation exposure tracking of the patients.

  14. Organ dose calculation in CT based on scout image data and automatic image registration

    International Nuclear Information System (INIS)

    Background Computed tomography (CT) has become the main contributor of the cumulative radiation exposure in radiology. Information on cumulative exposure history of the patient should be available for efficient management of radiation exposures and for radiological justification. Purpose To develop and evaluate automatic image registration for organ dose calculation in CT. Material and Methods Planning radiograph (scout) image data describing CT scan ranges from 15 thoracic CT examinations (9 men and 6 women) and 10 abdominal CT examinations (6 men and 4 women) were co-registered with the reference trunk CT scout image. 2-D affine transformation and normalized correlation metric was used for image registration. Longitudinal (z-axis) scan range coordinates on the reference scout image were converted into slice locations on the CT-Expo anthropomorphic male and female models, following organ and effective dose calculations. Results The average deviation of z-location of studied patient images from the corresponding location in the reference scout image was 6.2 mm. The ranges of organ and effective doses with constant exposure parameters were from 0 to 28.0 mGy and from 7.3 to 14.5 mSv, respectively. The mean deviation of the doses for fully irradiated organs (inside the scan range), partially irradiated organs and non-irradiated organs (outside the scan range) was 1%, 5%, and 22%, respectively, due to image registration. Conclusion The automated image processing method to registrate individual chest and abdominal CT scout radiograph with the reference scout radiograph is feasible. It can be used to determine the individual scan range coordinates in z-direction to calculate the organ dose values. The presented method could be utilized in automatic organ dose calculation in CT for radiation exposure tracking of the patients

  15. Image reconstruction using a first generation CT scanner

    International Nuclear Information System (INIS)

    Computed tomography (CT) is a non-destructive imaging technique that has been used in medical diagnosis since 1971. For many years the CT technique has also been applied to material characterisation and the detection of defects and flaws in industrial components associated with the nuclear, aerospace and missile industries. This paper reports on the construction of a first generation CT scanner built to demonstrate some applications of CT in the field of non-destructive testing and characterisation of materials. The scanner uses a mono-energetic 667 keV Cs-137 gamma radiation source and sodium iodide detector. The analogue output of the detector is connected to a Minekin rate meter. The object is placed on a specimen stage with the movement controlled by stepper motors through a GPIB interface. The projection data is acquired by placing the object at various angles with respect to the incident radiation and scanning the object laterally through a fixed source and detector assembly. The attenuation data is then processed on a Pentium computer using the summation filtered back-projection image reconstruction method. The mass attenuation coefficients were measured for aluminium, stainless steel, brass and lead and the results compared favourably with published data. The CT scanner will be improved to study various other applications in materials science and be used to establish a modern computed tomographic scanning facility. (author)

  16. Imaging lobular breast carcinoma: comparison of synchrotron radiation DEI-CT technique with clinical CT, mammography and histology

    Energy Technology Data Exchange (ETDEWEB)

    Fiedler, S [European Synchrotron Radiation Facility, BP 220, F-38043 Grenoble Cedex (France); Bravin, A [European Synchrotron Radiation Facility, BP 220, F-38043 Grenoble Cedex (France); Keyrilaeinen, J [Department of Physical Sciences, POB 64, FIN-00014 Helsinki University (Finland); Fernandez, M [Department of Physical Sciences, POB 64, FIN-00014 Helsinki University (Finland); Suortti, P [Department of Physical Sciences, POB 64, FIN-00014 Helsinki University (Finland); Thomlinson, W [European Synchrotron Radiation Facility, BP 220, F-38043 Grenoble Cedex (France); Tenhunen, M [Department of Oncology, Helsinki University Central Hospital, POB 180, FIN-00029 HUS (Finland); Virkkunen, P [Department of Oncology, Helsinki University Central Hospital, POB 180, FIN-00029 HUS (Finland); Karjalainen-Lindsberg, M-L [Department of Pathology, HUCH Laboratory Diagnostics, Helsinki University Central Hospital, POB 400, FIN-00029 HUS (Finland)

    2004-01-21

    Different modalities for imaging cancer-bearing breast tissue samples are described and compared. The images include clinical mammograms and computed tomography (CT) images, CT images with partly coherent synchrotron radiation (SR), and CT and radiography images taken with SR using the diffraction enhanced imaging (DEI) method. The images are evaluated by a radiologist and compared with histopathological examination of the samples. Two cases of lobular carcinoma are studied in detail. The indications of cancer are very weak or invisible in the conventional images, but the morphological changes due to invasion of cancer become pronounced in the images taken by the DEI method. The strands penetrating adipose tissue are seen clearly in the DEI-CT images, and the histopathology confirms that some strands contain the so-called 'Indian file' formations of cancer cells. The radiation dose is carefully measured for each of the imaging modalities. The mean glandular dose (MGD) for 50% glandular breast tissue is about 1 mGy in conventional mammography and less than 0.25 mGy in projection DEI, while in the clinical CT imaging the MGD is very high, about 45 mGy. The entrance dose of 95 mGy in DEI-CT imaging gives rise to an MGD of 40 mGy, but the dose may be reduced by an order of magnitude, because the contrast is very large in most images.

  17. Reconstruction of CT images by the Bayes- back projection method

    CERN Document Server

    Haruyama, M; Takase, M; Tobita, H

    2002-01-01

    In the course of research on quantitative assay of non-destructive measurement of radioactive waste, the have developed a unique program based on the Bayesian theory for reconstruction of transmission computed tomography (TCT) image. The reconstruction of cross-section images in the CT technology usually employs the Filtered Back Projection method. The new imaging reconstruction program reported here is based on the Bayesian Back Projection method, and it has a function of iterative improvement images by every step of measurement. Namely, this method has the capability of prompt display of a cross-section image corresponding to each angled projection data from every measurement. Hence, it is possible to observe an improved cross-section view by reflecting each projection data in almost real time. From the basic theory of Baysian Back Projection method, it can be not only applied to CT types of 1st, 2nd, and 3rd generation. This reported deals with a reconstruction program of cross-section images in the CT of ...

  18. Clinical evaluation of multiplanar reformation CT images in disk hernias

    International Nuclear Information System (INIS)

    Computed tomography (CT) is a non-invasive procedure as compared with myelography in the diagnosis of diseases of the spine and spinal cord. In recent years, the performance of the CT-scan equipment has been markedly improved, resulting in an advancement of its diagnostic value, and it is said that CT is now superior to myelography in diagnosing some types of diseases of spine and spinal cord. We performed a multiplanar reformation in patients with disk hernia for the purpose of evaluating the method's clinical diagnostic value, and the reformatted images were compared with the axial images in the same patient. We used four types of reformation: coronal, sagittal, para-axial, and oblique reformations. The reformatted images were obtained from multiple continuous images with a slice thickness of 3 mm and with no declination of the gantry of the scanner. The axial images were obtained by making the gantry parallel to the disk and perpendicular to the vertebral body. The thickness of the axial images is 3 mm at the disk and 5 mm at the vertebral body level. We compared these reformatted and axial images with the extension of the disk hernia in the spinal canal and neural foramen and the degree of visualization of nerve roots. The sagittal reformatted images were useful in evaluating the extension of the disk hernia in the spinal canal and neural foramen. The coronal and oblique reformatted images were useful in visualizing the nerve roots. The axial images were excellent in ability to diagnose the disk hernia, while the reformatted images were significant in understanding the anatomical relation of the disease preoperatively. (author)

  19. A study for image quality and patient doses during head and abdominal examination for nine CT scanners in Macedonia

    International Nuclear Information System (INIS)

    Many private diagnostic practices in Macedonia have started with Computed Tomography (CT) imaging for the last decade. The number and range of CT applications became more available to physicians and the patients. With this increased use of CT examinations, the potential risks from the radiation dose have been increased also. Quality Control tests were performed to nine of 22 CT scanners in Macedonia. Weighted CTDIw (Computed Tomography Dose Index) parameter was calculated for abdominal and brain clinical examination. Those values were compared to CT European Criteria for radiation dose. In addition, CTDIw was calculated at unique technical protocol for all CT scanners. Patient doses for head and abdominal examination were assessed using those CTDIw corrected for CTDIair values, scan length for head and abdomen, conversion factors and typical CT scanner category factors. The parameters that characterize the image quality were assessed by CATPHAN 500 phantom, rayed on typical clinical protocols for high resolution and low contrast detestability. In this work, the values for High Resolution and Low Contrast Detectability are presented for each CT scanner. (author)

  20. Characteristics of meningioma scintigraphy with multiple brain imaging agents

    International Nuclear Information System (INIS)

    Purpose: To clarify the characteristics of meningioma scintigraphy with multiple brain imaging agents and to evaluate their roles in diagnosis of meningiomas. Methods: Blood flow, 99mTc-ECD, 99mTc-DTPA, and/or 99mTc-MIBI brain imagings were performed in 21 patients with meningiomas (3 malignant, 18 benign) proved by surgery and pathology. CT/MRI examinations were also made within one month. Characteristics of meningioma images were analyzed and uptake ratios were calculated. Results: In 16 of 20 patients, increased radioactivity during the arterial phase in the blood flow image was seen. Concave round or oval defects with smooth contour in the cerebral cortex were observed in 17 of 19 patients with 99mTc-ECD, depression of frontoparietal cortex was found in one case and no abnormality in the other. A homogeneous accumulation of radioactivity in area corresponding to the defect in 99mTc-ECD image was found in 17/17 patients with 99mTc-DTPA and in 14/14 patients with 99mTc-MIBI study. No correlation was found between uptake ratios of the three tracers, but 99mTc-ECD uptake ratio was significantly lower in malignant meningioma than in benign one. Conclusions: The combined use of 99mTc-ECD and 99mTc-DTPA and/or 99mTc-MIBI brain imaging is useful in making the diagnosis of meningiomas. Whether the 99mTc-ECD uptake ratio will be valuable to differentiate malignant from benign meningioma needs further studies

  1. The role of dual energy CT in differentiating between brain haemorrhage and contrast medium after mechanical revascularisation in acute ischaemic stroke

    Energy Technology Data Exchange (ETDEWEB)

    Tijssen, M.P.M.; Stadler, A.A.R.; Zwam, W. van; Graaf, R. de; Postma, A.A. [Maastricht University Medical Centre, Department of Radiology, P.O. Box 5800, Maastricht (Netherlands); Hofman, P.A.M. [Maastricht University Medical Centre, Department of Radiology, P.O. Box 5800, Maastricht (Netherlands); Maastricht University, MhENS School for Mental Health and Neuroscience, Maastricht (Netherlands); Oostenbrugge, R.J. van [Maastricht University Medical Centre, Department of Neurology, P.O. Box 5800, Maastricht (Netherlands); Maastricht University, CARIM School for Cardiovascular Diseases, P.O. Box 616, Maastricht (Netherlands); Klotz, E. [Siemens Healthcare Sector, Computed Tomography, Forchheim (Germany); Wildberger, J.E. [Maastricht University Medical Centre, Department of Radiology, P.O. Box 5800, Maastricht (Netherlands); Maastricht University, CARIM School for Cardiovascular Diseases, P.O. Box 616, Maastricht (Netherlands)

    2014-04-15

    To assess the feasibility of dual energy computed tomography (DE-CT) in intra-arterially treated acute ischaemic stroke patients to discriminate between contrast extravasation and intracerebral haemorrhage. Thirty consecutive acute ischaemic stroke patients following intra-arterial treatment were examined with DE-CT. Simultaneous imaging at 80 kV and 140 kV was employed with calculation of mixed images. Virtual unenhanced non-contrast (VNC) images and iodine overlay maps (IOM) were calculated using a dedicated brain haemorrhage algorithm. Mixed images alone, as ''conventional CT'', and DE-CT interpretations were evaluated and compared with follow-up CT. Eight patients were excluded owing to a lack of follow-up or loss of data. Mixed images showed intracerebral hyperdense areas in 19/22 patients. Both haemorrhage and residual contrast material were present in 1/22. IOM suggested contrast extravasation in 18/22 patients; in 16/18 patients this was confirmed at follow-up. The positive predictive value (PPV) of mixed imaging alone was 25 %, with a negative predictive value (NPV) of 91 % and accuracy of 63 %. The PPV for detection of haemorrhage with DE-CT was 100 %, with an NPV of 89 % and accuracy improved to 89 %. Dual energy computed tomography improves accuracy and diagnostic confidence in early differentiation between intracranial haemorrhage and contrast medium extravasation in acute stroke patients following intra-arterial revascularisation. (orig.)

  2. Myocardial perfusion imaging using SPECT/CT and PET/CT

    International Nuclear Information System (INIS)

    With technical progress coronary CT angiography is increasingly accepted as a noninvasive alternative in morphological imaging. However, image quality and interpretation are still influenced by various factors like blooming artifacts, misregistration and the experience of the interpreter. The combination with stress-rest myocardial perfusion SPECT or PET as a hybrid scanner or two standalone scanners enables comprehensive noninvasive anatomical and functional imaging of the heart as well as three dimensional image fusion. Hybrid-imaging is feasible with today's commercially available software packages but still requires time demanding manual intervention and experienced interpretation. PET investigations, either in replacement of SPECT for perfusion measurements, or in addition with new biomarkers will provide even more impact to hybrid imaging in future. (orig.)

  3. Diagnostic study with CT and MR on the metastasis of malignant brain tumors

    International Nuclear Information System (INIS)

    Forty cases of malignant brain tumors with metastasis which involved 14 malignant gliomas, 15 medulloblastomas and 11 germ cell tumors were studied on CT and MRI. In malignant glioma, transventricular metastasis was seen most frequently, estimating 8 cases (57%) of 14 malignant gliomas with metastasis and showing ependymal-subependymal enhancement on contrast-enhanced CT (CECT). Most of the medulloblastoma with metastasis demonstrated diffuse subarachnoid seeding in the craniospinal space and on image analysis diffuse sulcal-cisternal enhancement was characterized. Trans-ventricular metastasis in medulloblastoma was less than in malignant glioma showing 3 cases (20%) of 15 medulloblastomas, which in most cases showed a nodular tumor in the ventricular wall by metastasis. There were six patients who, on the first admission, were found to have germ cell tumors of the broad infiltrating type with multiple lesions. The tumor sites of metastasis were different from those with malignant gliomas, being frequently localized in the pineal and/or the suprasellar region, on the ventricular wall and in the basal ganglia. Metastasis to a remote area in germ cell tumors was to spinal cords, to the ventricular wall and basal cistern around the brain stem by CSF dissemination, to the lung by hematogenous metastasis and to the peritoneal wall or organs through V-P shunt tube. T1-weighted Gd-DTPA MRI was more useful and sensitive than CECT for diagnosis of the leptomeningeal metastasis, particularly for sulcal-cisternal and spinal metastasis. It will be used more often as the first choice for diagnosis of intrathecal metastasis in the future. (author)

  4. Diagnostic study with CT and MR on the metastasis of malignant brain tumors

    Energy Technology Data Exchange (ETDEWEB)

    Miyagami, Mitsusuke; Kasahara, Eishi; Tazoe, Makoto; Tsubokawa, Takashi (Nihon Univ., Tokyo (Japan). School of Medicine)

    1990-08-01

    Forty cases of malignant brain tumors with metastasis which involved 14 malignant gliomas, 15 medulloblastomas and 11 germ cell tumors were studied on CT and MRI. In malignant glioma, transventricular metastasis was seen most frequently, estimating 8 cases (57%) of 14 malignant gliomas with metastasis and showing ependymal-subependymal enhancement on contrast-enhanced CT (CECT). Most of the medulloblastoma with metastasis demonstrated diffuse subarachnoid seeding in the craniospinal space and on image analysis diffuse sulcal-cisternal enhancement was characterized. Trans-ventricular metastasis in medulloblastoma was less than in malignant glioma showing 3 cases (20%) of 15 medulloblastomas, which in most cases showed a nodular tumor in the ventricular wall by metastasis. There were six patients who, on the first admission, were found to have germ cell tumors of the broad infiltrating type with multiple lesions. The tumor sites of metastasis were different from those with malignant gliomas, being frequently localized in the pineal and/or the suprasellar region, on the ventricular wall and in the basal ganglia. Metastasis to a remote area in germ cell tumors was to spinal cords, to the ventricular wall and basal cistern around the brain stem by CSF dissemination, to the lung by hematogenous metastasis and to the peritoneal wall or organs through V-P shunt tube. T{sub 1}-weighted Gd-DTPA MRI was more useful and sensitive than CECT for diagnosis of the leptomeningeal metastasis, particularly for sulcal-cisternal and spinal metastasis. It will be used more often as the first choice for diagnosis of intrathecal metastasis in the future. (author).

  5. Estimating CT Image from MRI Data Using Structured Random Forest and Auto-context Model

    OpenAIRE

    Huynh, Tri; Gao, Yaozong; Kang, Jiayin; Wang, Li; Zhang, Pei; Lian, Jun; Shen, Dinggang

    2015-01-01

    Computed tomography (CT) imaging is an essential tool in various clinical diagnoses and radiotherapy treatment planning. Since CT image intensities are directly related to positron emission tomography (PET) attenuation coefficients, they are indispensable for attenuation correction (AC) of the PET images. However, due to the relatively high dose of radiation exposure in CT scan, it is advised to limit the acquisition of CT images. In addition, in the new PET and magnetic resonance (MR) imagin...

  6. Correlating Micro-CT Imaging with Quantitative Histology

    Czech Academy of Sciences Publication Activity Database

    Gregor, T.; Kochová, P.; Eberlová, L.; Nedorost, L.; Prosecká, Eva; Liška, V.; Mírka, H.; Kachlík, D.; Pirner, I.; Zimmermann, P.; Králíčková, A.; Králíčková, M.; Tonar, Z.

    Rijeka: InTech Open Access Publisher, 2012 - (Goswami, T.), s. 173-196 ISBN 978-953-51-0690-6 R&D Projects: GA ČR GAP304/10/1307 Grant ostatní: GA ČR(CZ) GA106/09/0740; GA UK(CZ) GAUK 96610; GA MZd(CZ) NT13326 Institutional research plan: CEZ:AV0Z50390512; CEZ:AV0Z50390703 Keywords : micro CT * quantitative Histology * biomechanical models Subject RIV: FP - Other Medical Disciplines http://www.intechopen.com/books/injury-and-skeletal-biomechanics/correlating-micro-ct-imaging-with-quantitative-histology